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putty-source/ssh/connection1.c

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Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
/*
* Packet protocol layer for the SSH-1 'connection protocol', i.e.
* everything after authentication finishes.
*/
#include <assert.h>
#include "putty.h"
#include "ssh.h"
Move the SSH implementation into its own subdirectory. This clears up another large pile of clutter at the top level, and in the process, allows me to rename source files to things that don't all have that annoying 'ssh' prefix at the top.
2021-04-22 16:58:40 +00:00
#include "bpp.h"
#include "ppl.h"
#include "channel.h"
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
#include "sshcr.h"
Move the SSH implementation into its own subdirectory. This clears up another large pile of clutter at the top level, and in the process, allows me to rename source files to things that don't all have that annoying 'ssh' prefix at the top.
2021-04-22 16:58:40 +00:00
#include "connection1.h"
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
static int ssh1_rportfwd_cmp(void *av, void *bv)
{
struct ssh_rportfwd *a = (struct ssh_rportfwd *) av;
struct ssh_rportfwd *b = (struct ssh_rportfwd *) bv;
int i;
if ( (i = strcmp(a->dhost, b->dhost)) != 0)
Whitespace rationalisation of entire code base. The number of people has been steadily increasing who read our source code with an editor that thinks tab stops are 4 spaces apart, as opposed to the traditional tty-derived 8 that the PuTTY code expects. So I've been wondering for ages about just fixing it, and switching to a spaces-only policy throughout the code. And I recently found out about 'git blame -w', which should make this change not too disruptive for the purposes of source-control archaeology; so perhaps now is the time. While I'm at it, I've also taken the opportunity to remove all the trailing spaces from source lines (on the basis that git dislikes them, and is the only thing that seems to have a strong opinion one way or the other). Apologies to anyone downstream of this code who has complicated patch sets to rebase past this change. I don't intend it to be needed again.
2019-09-08 19:29:00 +00:00
return i < 0 ? -1 : +1;
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
if (a->dport > b->dport)
Whitespace rationalisation of entire code base. The number of people has been steadily increasing who read our source code with an editor that thinks tab stops are 4 spaces apart, as opposed to the traditional tty-derived 8 that the PuTTY code expects. So I've been wondering for ages about just fixing it, and switching to a spaces-only policy throughout the code. And I recently found out about 'git blame -w', which should make this change not too disruptive for the purposes of source-control archaeology; so perhaps now is the time. While I'm at it, I've also taken the opportunity to remove all the trailing spaces from source lines (on the basis that git dislikes them, and is the only thing that seems to have a strong opinion one way or the other). Apologies to anyone downstream of this code who has complicated patch sets to rebase past this change. I don't intend it to be needed again.
2019-09-08 19:29:00 +00:00
return +1;
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
if (a->dport < b->dport)
Whitespace rationalisation of entire code base. The number of people has been steadily increasing who read our source code with an editor that thinks tab stops are 4 spaces apart, as opposed to the traditional tty-derived 8 that the PuTTY code expects. So I've been wondering for ages about just fixing it, and switching to a spaces-only policy throughout the code. And I recently found out about 'git blame -w', which should make this change not too disruptive for the purposes of source-control archaeology; so perhaps now is the time. While I'm at it, I've also taken the opportunity to remove all the trailing spaces from source lines (on the basis that git dislikes them, and is the only thing that seems to have a strong opinion one way or the other). Apologies to anyone downstream of this code who has complicated patch sets to rebase past this change. I don't intend it to be needed again.
2019-09-08 19:29:00 +00:00
return -1;
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
return 0;
}
Whitespace rationalisation of entire code base. The number of people has been steadily increasing who read our source code with an editor that thinks tab stops are 4 spaces apart, as opposed to the traditional tty-derived 8 that the PuTTY code expects. So I've been wondering for ages about just fixing it, and switching to a spaces-only policy throughout the code. And I recently found out about 'git blame -w', which should make this change not too disruptive for the purposes of source-control archaeology; so perhaps now is the time. While I'm at it, I've also taken the opportunity to remove all the trailing spaces from source lines (on the basis that git dislikes them, and is the only thing that seems to have a strong opinion one way or the other). Apologies to anyone downstream of this code who has complicated patch sets to rebase past this change. I don't intend it to be needed again.
2019-09-08 19:29:00 +00:00
static void ssh1_connection_free(PacketProtocolLayer *);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
static void ssh1_connection_process_queue(PacketProtocolLayer *);
static void ssh1_connection_special_cmd(PacketProtocolLayer *ppl,
SessionSpecialCode code, int arg);
static void ssh1_connection_reconfigure(PacketProtocolLayer *ppl, Conf *conf);
Change vtable defs to use C99 designated initialisers. This is a sweeping change applied across the whole code base by a spot of Emacs Lisp. Now, everywhere I declare a vtable filled with function pointers (and the occasional const data member), all the members of the vtable structure are initialised by name using the '.fieldname = value' syntax introduced in C99. We were already using this syntax for a handful of things in the new key-generation progress report system, so it's not new to the code base as a whole. The advantage is that now, when a vtable only declares a subset of the available fields, I can initialise the rest to NULL or zero just by leaving them out. This is most dramatic in a couple of the outlying vtables in things like psocks (which has a ConnectionLayerVtable containing only one non-NULL method), but less dramatically, it means that the new 'flags' field in BackendVtable can be completely left out of every backend definition except for the SUPDUP one which defines it to a nonzero value. Similarly, the test_for_upstream method only used by SSH doesn't have to be mentioned in the rest of the backends; network Plugs for listening sockets don't have to explicitly null out 'receive' and 'sent', and vice versa for 'accepting', and so on. While I'm at it, I've normalised the declarations so they don't use the unnecessarily verbose 'struct' keyword. Also a handful of them weren't const; now they are.
2020-03-10 21:06:29 +00:00
static const PacketProtocolLayerVtable ssh1_connection_vtable = {
.free = ssh1_connection_free,
.process_queue = ssh1_connection_process_queue,
.get_specials = ssh1_common_get_specials,
.special_cmd = ssh1_connection_special_cmd,
.reconfigure = ssh1_connection_reconfigure,
.queued_data_size = ssh_ppl_default_queued_data_size,
Packet protocol layers: new 'final_output' method. This is called just before closing the connection, and gives every PPL one last chance to output anything to the user that it might have buffered. No functional change: all implementations so far are trivial, except that the transport layer passes the call on to its higher layer (because otherwise nothing would do so).
2023-04-29 10:35:20 +00:00
.final_output = ssh_ppl_default_final_output,
Change vtable defs to use C99 designated initialisers. This is a sweeping change applied across the whole code base by a spot of Emacs Lisp. Now, everywhere I declare a vtable filled with function pointers (and the occasional const data member), all the members of the vtable structure are initialised by name using the '.fieldname = value' syntax introduced in C99. We were already using this syntax for a handful of things in the new key-generation progress report system, so it's not new to the code base as a whole. The advantage is that now, when a vtable only declares a subset of the available fields, I can initialise the rest to NULL or zero just by leaving them out. This is most dramatic in a couple of the outlying vtables in things like psocks (which has a ConnectionLayerVtable containing only one non-NULL method), but less dramatically, it means that the new 'flags' field in BackendVtable can be completely left out of every backend definition except for the SUPDUP one which defines it to a nonzero value. Similarly, the test_for_upstream method only used by SSH doesn't have to be mentioned in the rest of the backends; network Plugs for listening sockets don't have to explicitly null out 'receive' and 'sent', and vice versa for 'accepting', and so on. While I'm at it, I've normalised the declarations so they don't use the unnecessarily verbose 'struct' keyword. Also a handful of them weren't const; now they are.
2020-03-10 21:06:29 +00:00
.name = NULL, /* no layer names in SSH-1 */
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
};
static void ssh1_rportfwd_remove(
ConnectionLayer *cl, struct ssh_rportfwd *rpf);
static SshChannel *ssh1_lportfwd_open(
ConnectionLayer *cl, const char *hostname, int port,
Rename SocketPeerInfo to SocketEndpointInfo. I'm preparing to be able to ask about the other end of the connection too, so the first step is to give this data structure a neutral name that can refer to either. No functional change yet.
2024-06-26 05:35:40 +00:00
const char *description, const SocketEndpointInfo *pi, Channel *chan);
Rewrite the SSH-1 main shell session using mainchan. In SSH-1, the channel system isn't rich enough to represent the complicated main shell session, so it's all done with a separate set of custom message types. But PuTTY now abstracts away that difference, by representing both as different implementations of the SshChannel class: ssh1channel is for things that the protocol thinks are 'really' channels, and ssh1mainchan is for the shell session. All the same methods are implemented, but generate different wire messages. This means that the logic to decide _when_ to enable X forwarding, agent forwarding etc is all centralised into mainchan.c, where it doesn't have to be repeated for both protocol versions. It also simplifies the final loop in the connection protocol, which no longer has to contain the code to move data from the user input bufchain to the channel's output; that's now done by the mainchan write method, the same as it is in SSH-2 where mainchan is just like other channels.
2018-09-30 10:22:01 +00:00
static struct X11FakeAuth *ssh1_add_x11_display(
ConnectionLayer *cl, int authtype, struct X11Display *disp);
Convert a lot of 'int' variables to 'bool'. My normal habit these days, in new code, is to treat int and bool as _almost_ completely separate types. I'm still willing to use C's implicit test for zero on an integer (e.g. 'if (!blob.len)' is fine, no need to spell it out as blob.len != 0), but generally, if a variable is going to be conceptually a boolean, I like to declare it bool and assign to it using 'true' or 'false' rather than 0 or 1. PuTTY is an exception, because it predates the C99 bool, and I've stuck to its existing coding style even when adding new code to it. But it's been annoying me more and more, so now that I've decided C99 bool is an acceptable thing to require from our toolchain in the first place, here's a quite thorough trawl through the source doing 'boolification'. Many variables and function parameters are now typed as bool rather than int; many assignments of 0 or 1 to those variables are now spelled 'true' or 'false'. I managed this thorough conversion with the help of a custom clang plugin that I wrote to trawl the AST and apply heuristics to point out where things might want changing. So I've even managed to do a decent job on parts of the code I haven't looked at in years! To make the plugin's work easier, I pushed platform front ends generally in the direction of using standard 'bool' in preference to platform-specific boolean types like Windows BOOL or GTK's gboolean; I've left the platform booleans in places they _have_ to be for the platform APIs to work right, but variables only used by my own code have been converted wherever I found them. In a few places there are int values that look very like booleans in _most_ of the places they're used, but have a rarely-used third value, or a distinction between different nonzero values that most users don't care about. In these cases, I've _removed_ uses of 'true' and 'false' for the return values, to emphasise that there's something more subtle going on than a simple boolean answer: - the 'multisel' field in dialog.h's list box structure, for which the GTK front end in particular recognises a difference between 1 and 2 but nearly everything else treats as boolean - the 'urgent' parameter to plug_receive, where 1 vs 2 tells you something about the specific location of the urgent pointer, but most clients only care about 0 vs 'something nonzero' - the return value of wc_match, where -1 indicates a syntax error in the wildcard. - the return values from SSH-1 RSA-key loading functions, which use -1 for 'wrong passphrase' and 0 for all other failures (so any caller which already knows it's not loading an _encrypted private_ key can treat them as boolean) - term->esc_query, and the 'query' parameter in toggle_mode in terminal.c, which _usually_ hold 0 for ESC[123h or 1 for ESC[?123h, but can also hold -1 for some other intervening character that we don't support. In a few places there's an integer that I haven't turned into a bool even though it really _can_ only take values 0 or 1 (and, as above, tried to make the call sites consistent in not calling those values true and false), on the grounds that I thought it would make it more confusing to imply that the 0 value was in some sense 'negative' or bad and the 1 positive or good: - the return value of plug_accepting uses the POSIXish convention of 0=success and nonzero=error; I think if I made it bool then I'd also want to reverse its sense, and that's a job for a separate piece of work. - the 'screen' parameter to lineptr() in terminal.c, where 0 and 1 represent the default and alternate screens. There's no obvious reason why one of those should be considered 'true' or 'positive' or 'success' - they're just indices - so I've left it as int. ssh_scp_recv had particularly confusing semantics for its previous int return value: its call sites used '<= 0' to check for error, but it never actually returned a negative number, just 0 or 1. Now the function and its call sites agree that it's a bool. In a couple of places I've renamed variables called 'ret', because I don't like that name any more - it's unclear whether it means the return value (in preparation) for the _containing_ function or the return value received from a subroutine call, and occasionally I've accidentally used the same variable for both and introduced a bug. So where one of those got in my way, I've renamed it to 'toret' or 'retd' (the latter short for 'returned') in line with my usual modern practice, but I haven't done a thorough job of finding all of them. Finally, one amusing side effect of doing this is that I've had to separate quite a few chained assignments. It used to be perfectly fine to write 'a = b = c = TRUE' when a,b,c were int and TRUE was just a the 'true' defined by stdbool.h, that idiom provokes a warning from gcc: 'suggest parentheses around assignment used as truth value'!
2018-11-02 19:23:19 +00:00
static bool ssh1_agent_forwarding_permitted(ConnectionLayer *cl);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
static void ssh1_terminal_size(ConnectionLayer *cl, int width, int height);
Make lots of 'int' length fields into size_t. This is a general cleanup which has been overdue for some time: lots of length fields are now the machine word type rather than the (in practice) fixed 'int'.
2019-02-06 20:42:44 +00:00
static void ssh1_stdout_unthrottle(ConnectionLayer *cl, size_t bufsize);
static size_t ssh1_stdin_backlog(ConnectionLayer *cl);
Convert a lot of 'int' variables to 'bool'. My normal habit these days, in new code, is to treat int and bool as _almost_ completely separate types. I'm still willing to use C's implicit test for zero on an integer (e.g. 'if (!blob.len)' is fine, no need to spell it out as blob.len != 0), but generally, if a variable is going to be conceptually a boolean, I like to declare it bool and assign to it using 'true' or 'false' rather than 0 or 1. PuTTY is an exception, because it predates the C99 bool, and I've stuck to its existing coding style even when adding new code to it. But it's been annoying me more and more, so now that I've decided C99 bool is an acceptable thing to require from our toolchain in the first place, here's a quite thorough trawl through the source doing 'boolification'. Many variables and function parameters are now typed as bool rather than int; many assignments of 0 or 1 to those variables are now spelled 'true' or 'false'. I managed this thorough conversion with the help of a custom clang plugin that I wrote to trawl the AST and apply heuristics to point out where things might want changing. So I've even managed to do a decent job on parts of the code I haven't looked at in years! To make the plugin's work easier, I pushed platform front ends generally in the direction of using standard 'bool' in preference to platform-specific boolean types like Windows BOOL or GTK's gboolean; I've left the platform booleans in places they _have_ to be for the platform APIs to work right, but variables only used by my own code have been converted wherever I found them. In a few places there are int values that look very like booleans in _most_ of the places they're used, but have a rarely-used third value, or a distinction between different nonzero values that most users don't care about. In these cases, I've _removed_ uses of 'true' and 'false' for the return values, to emphasise that there's something more subtle going on than a simple boolean answer: - the 'multisel' field in dialog.h's list box structure, for which the GTK front end in particular recognises a difference between 1 and 2 but nearly everything else treats as boolean - the 'urgent' parameter to plug_receive, where 1 vs 2 tells you something about the specific location of the urgent pointer, but most clients only care about 0 vs 'something nonzero' - the return value of wc_match, where -1 indicates a syntax error in the wildcard. - the return values from SSH-1 RSA-key loading functions, which use -1 for 'wrong passphrase' and 0 for all other failures (so any caller which already knows it's not loading an _encrypted private_ key can treat them as boolean) - term->esc_query, and the 'query' parameter in toggle_mode in terminal.c, which _usually_ hold 0 for ESC[123h or 1 for ESC[?123h, but can also hold -1 for some other intervening character that we don't support. In a few places there's an integer that I haven't turned into a bool even though it really _can_ only take values 0 or 1 (and, as above, tried to make the call sites consistent in not calling those values true and false), on the grounds that I thought it would make it more confusing to imply that the 0 value was in some sense 'negative' or bad and the 1 positive or good: - the return value of plug_accepting uses the POSIXish convention of 0=success and nonzero=error; I think if I made it bool then I'd also want to reverse its sense, and that's a job for a separate piece of work. - the 'screen' parameter to lineptr() in terminal.c, where 0 and 1 represent the default and alternate screens. There's no obvious reason why one of those should be considered 'true' or 'positive' or 'success' - they're just indices - so I've left it as int. ssh_scp_recv had particularly confusing semantics for its previous int return value: its call sites used '<= 0' to check for error, but it never actually returned a negative number, just 0 or 1. Now the function and its call sites agree that it's a bool. In a couple of places I've renamed variables called 'ret', because I don't like that name any more - it's unclear whether it means the return value (in preparation) for the _containing_ function or the return value received from a subroutine call, and occasionally I've accidentally used the same variable for both and introduced a bug. So where one of those got in my way, I've renamed it to 'toret' or 'retd' (the latter short for 'returned') in line with my usual modern practice, but I haven't done a thorough job of finding all of them. Finally, one amusing side effect of doing this is that I've had to separate quite a few chained assignments. It used to be perfectly fine to write 'a = b = c = TRUE' when a,b,c were int and TRUE was just a the 'true' defined by stdbool.h, that idiom provokes a warning from gcc: 'suggest parentheses around assignment used as truth value'!
2018-11-02 19:23:19 +00:00
static void ssh1_throttle_all_channels(ConnectionLayer *cl, bool throttled);
static bool ssh1_ldisc_option(ConnectionLayer *cl, int option);
static void ssh1_set_ldisc_option(ConnectionLayer *cl, int option, bool value);
Rewrite the SSH-1 main shell session using mainchan. In SSH-1, the channel system isn't rich enough to represent the complicated main shell session, so it's all done with a separate set of custom message types. But PuTTY now abstracts away that difference, by representing both as different implementations of the SshChannel class: ssh1channel is for things that the protocol thinks are 'really' channels, and ssh1mainchan is for the shell session. All the same methods are implemented, but generate different wire messages. This means that the logic to decide _when_ to enable X forwarding, agent forwarding etc is all centralised into mainchan.c, where it doesn't have to be repeated for both protocol versions. It also simplifies the final loop in the connection protocol, which no longer has to contain the code to move data from the user input bufchain to the channel's output; that's now done by the mainchan write method, the same as it is in SSH-2 where mainchan is just like other channels.
2018-09-30 10:22:01 +00:00
static void ssh1_enable_x_fwd(ConnectionLayer *cl);
Convert a lot of 'int' variables to 'bool'. My normal habit these days, in new code, is to treat int and bool as _almost_ completely separate types. I'm still willing to use C's implicit test for zero on an integer (e.g. 'if (!blob.len)' is fine, no need to spell it out as blob.len != 0), but generally, if a variable is going to be conceptually a boolean, I like to declare it bool and assign to it using 'true' or 'false' rather than 0 or 1. PuTTY is an exception, because it predates the C99 bool, and I've stuck to its existing coding style even when adding new code to it. But it's been annoying me more and more, so now that I've decided C99 bool is an acceptable thing to require from our toolchain in the first place, here's a quite thorough trawl through the source doing 'boolification'. Many variables and function parameters are now typed as bool rather than int; many assignments of 0 or 1 to those variables are now spelled 'true' or 'false'. I managed this thorough conversion with the help of a custom clang plugin that I wrote to trawl the AST and apply heuristics to point out where things might want changing. So I've even managed to do a decent job on parts of the code I haven't looked at in years! To make the plugin's work easier, I pushed platform front ends generally in the direction of using standard 'bool' in preference to platform-specific boolean types like Windows BOOL or GTK's gboolean; I've left the platform booleans in places they _have_ to be for the platform APIs to work right, but variables only used by my own code have been converted wherever I found them. In a few places there are int values that look very like booleans in _most_ of the places they're used, but have a rarely-used third value, or a distinction between different nonzero values that most users don't care about. In these cases, I've _removed_ uses of 'true' and 'false' for the return values, to emphasise that there's something more subtle going on than a simple boolean answer: - the 'multisel' field in dialog.h's list box structure, for which the GTK front end in particular recognises a difference between 1 and 2 but nearly everything else treats as boolean - the 'urgent' parameter to plug_receive, where 1 vs 2 tells you something about the specific location of the urgent pointer, but most clients only care about 0 vs 'something nonzero' - the return value of wc_match, where -1 indicates a syntax error in the wildcard. - the return values from SSH-1 RSA-key loading functions, which use -1 for 'wrong passphrase' and 0 for all other failures (so any caller which already knows it's not loading an _encrypted private_ key can treat them as boolean) - term->esc_query, and the 'query' parameter in toggle_mode in terminal.c, which _usually_ hold 0 for ESC[123h or 1 for ESC[?123h, but can also hold -1 for some other intervening character that we don't support. In a few places there's an integer that I haven't turned into a bool even though it really _can_ only take values 0 or 1 (and, as above, tried to make the call sites consistent in not calling those values true and false), on the grounds that I thought it would make it more confusing to imply that the 0 value was in some sense 'negative' or bad and the 1 positive or good: - the return value of plug_accepting uses the POSIXish convention of 0=success and nonzero=error; I think if I made it bool then I'd also want to reverse its sense, and that's a job for a separate piece of work. - the 'screen' parameter to lineptr() in terminal.c, where 0 and 1 represent the default and alternate screens. There's no obvious reason why one of those should be considered 'true' or 'positive' or 'success' - they're just indices - so I've left it as int. ssh_scp_recv had particularly confusing semantics for its previous int return value: its call sites used '<= 0' to check for error, but it never actually returned a negative number, just 0 or 1. Now the function and its call sites agree that it's a bool. In a couple of places I've renamed variables called 'ret', because I don't like that name any more - it's unclear whether it means the return value (in preparation) for the _containing_ function or the return value received from a subroutine call, and occasionally I've accidentally used the same variable for both and introduced a bug. So where one of those got in my way, I've renamed it to 'toret' or 'retd' (the latter short for 'returned') in line with my usual modern practice, but I haven't done a thorough job of finding all of them. Finally, one amusing side effect of doing this is that I've had to separate quite a few chained assignments. It used to be perfectly fine to write 'a = b = c = TRUE' when a,b,c were int and TRUE was just a the 'true' defined by stdbool.h, that idiom provokes a warning from gcc: 'suggest parentheses around assignment used as truth value'!
2018-11-02 19:23:19 +00:00
static void ssh1_set_wants_user_input(ConnectionLayer *cl, bool wanted);
Localise user_input to SSH connection layers. Now that the SSH backend's user_input bufchain is no longer needed for handling userpass input, it doesn't have to be awkwardly shared between all the packet protocol layers any more. So we can turn the want_user_input and got_user_input methods of PacketProtocolLayer into methods of ConnectionLayer, and then only the two connection layers have to bother implementing them, or store a pointer to the bufchain they read from.
2021-09-14 13:00:05 +00:00
static bool ssh1_get_wants_user_input(ConnectionLayer *cl);
static void ssh1_got_user_input(ConnectionLayer *cl);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
Change vtable defs to use C99 designated initialisers. This is a sweeping change applied across the whole code base by a spot of Emacs Lisp. Now, everywhere I declare a vtable filled with function pointers (and the occasional const data member), all the members of the vtable structure are initialised by name using the '.fieldname = value' syntax introduced in C99. We were already using this syntax for a handful of things in the new key-generation progress report system, so it's not new to the code base as a whole. The advantage is that now, when a vtable only declares a subset of the available fields, I can initialise the rest to NULL or zero just by leaving them out. This is most dramatic in a couple of the outlying vtables in things like psocks (which has a ConnectionLayerVtable containing only one non-NULL method), but less dramatically, it means that the new 'flags' field in BackendVtable can be completely left out of every backend definition except for the SUPDUP one which defines it to a nonzero value. Similarly, the test_for_upstream method only used by SSH doesn't have to be mentioned in the rest of the backends; network Plugs for listening sockets don't have to explicitly null out 'receive' and 'sent', and vice versa for 'accepting', and so on. While I'm at it, I've normalised the declarations so they don't use the unnecessarily verbose 'struct' keyword. Also a handful of them weren't const; now they are.
2020-03-10 21:06:29 +00:00
static const ConnectionLayerVtable ssh1_connlayer_vtable = {
.rportfwd_alloc = ssh1_rportfwd_alloc,
.rportfwd_remove = ssh1_rportfwd_remove,
.lportfwd_open = ssh1_lportfwd_open,
.session_open = ssh1_session_open,
.serverside_x11_open = ssh1_serverside_x11_open,
.serverside_agent_open = ssh1_serverside_agent_open,
.add_x11_display = ssh1_add_x11_display,
.agent_forwarding_permitted = ssh1_agent_forwarding_permitted,
.terminal_size = ssh1_terminal_size,
.stdout_unthrottle = ssh1_stdout_unthrottle,
.stdin_backlog = ssh1_stdin_backlog,
.throttle_all_channels = ssh1_throttle_all_channels,
.ldisc_option = ssh1_ldisc_option,
.set_ldisc_option = ssh1_set_ldisc_option,
.enable_x_fwd = ssh1_enable_x_fwd,
.set_wants_user_input = ssh1_set_wants_user_input,
Localise user_input to SSH connection layers. Now that the SSH backend's user_input bufchain is no longer needed for handling userpass input, it doesn't have to be awkwardly shared between all the packet protocol layers any more. So we can turn the want_user_input and got_user_input methods of PacketProtocolLayer into methods of ConnectionLayer, and then only the two connection layers have to bother implementing them, or store a pointer to the bufchain they read from.
2021-09-14 13:00:05 +00:00
.get_wants_user_input = ssh1_get_wants_user_input,
.got_user_input = ssh1_got_user_input,
Change vtable defs to use C99 designated initialisers. This is a sweeping change applied across the whole code base by a spot of Emacs Lisp. Now, everywhere I declare a vtable filled with function pointers (and the occasional const data member), all the members of the vtable structure are initialised by name using the '.fieldname = value' syntax introduced in C99. We were already using this syntax for a handful of things in the new key-generation progress report system, so it's not new to the code base as a whole. The advantage is that now, when a vtable only declares a subset of the available fields, I can initialise the rest to NULL or zero just by leaving them out. This is most dramatic in a couple of the outlying vtables in things like psocks (which has a ConnectionLayerVtable containing only one non-NULL method), but less dramatically, it means that the new 'flags' field in BackendVtable can be completely left out of every backend definition except for the SUPDUP one which defines it to a nonzero value. Similarly, the test_for_upstream method only used by SSH doesn't have to be mentioned in the rest of the backends; network Plugs for listening sockets don't have to explicitly null out 'receive' and 'sent', and vice versa for 'accepting', and so on. While I'm at it, I've normalised the declarations so they don't use the unnecessarily verbose 'struct' keyword. Also a handful of them weren't const; now they are.
2020-03-10 21:06:29 +00:00
/* other methods are NULL */
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
};
Make lots of 'int' length fields into size_t. This is a general cleanup which has been overdue for some time: lots of length fields are now the machine word type rather than the (in practice) fixed 'int'.
2019-02-06 20:42:44 +00:00
static size_t ssh1channel_write(
SshChannel *c, bool is_stderr, const void *buf, size_t len);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
static void ssh1channel_write_eof(SshChannel *c);
Rename sshfwd_unclean_close to sshfwd_initiate_close. Turns out that initiation of a CHANNEL_CLOSE message before both sides have sent EOF is not only for _unclean_ closures or emergencies; it's actually a perfectly normal thing that some channel types want to do. (For example, a channel with a pty at the server end of it has no real concept of sending EOF independently in both directions: when the pty master sends EIO, the pty is no longer functioning, and you can no longer send to it any more than you can receive.)
2018-10-13 09:30:03 +00:00
static void ssh1channel_initiate_close(SshChannel *c, const char *err);
Make lots of 'int' length fields into size_t. This is a general cleanup which has been overdue for some time: lots of length fields are now the machine word type rather than the (in practice) fixed 'int'.
2019-02-06 20:42:44 +00:00
static void ssh1channel_unthrottle(SshChannel *c, size_t bufsize);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
static Conf *ssh1channel_get_conf(SshChannel *c);
Fix segfault in SSH-1 X forwarding. The SSH-1 SshChannel vtable didn't bother to provide the window_override_removed method, because I wrongly remembered that it was only called when connection sharing. In fact, it's _called_ in any X forwarding, but it only has to _do_ anything when connection sharing: SSH-1 has to provide an empty implementation to avoid segfaulting by calling a null function pointer.
2018-10-13 15:30:59 +00:00
static void ssh1channel_window_override_removed(SshChannel *c) { /* ignore */ }
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
Change vtable defs to use C99 designated initialisers. This is a sweeping change applied across the whole code base by a spot of Emacs Lisp. Now, everywhere I declare a vtable filled with function pointers (and the occasional const data member), all the members of the vtable structure are initialised by name using the '.fieldname = value' syntax introduced in C99. We were already using this syntax for a handful of things in the new key-generation progress report system, so it's not new to the code base as a whole. The advantage is that now, when a vtable only declares a subset of the available fields, I can initialise the rest to NULL or zero just by leaving them out. This is most dramatic in a couple of the outlying vtables in things like psocks (which has a ConnectionLayerVtable containing only one non-NULL method), but less dramatically, it means that the new 'flags' field in BackendVtable can be completely left out of every backend definition except for the SUPDUP one which defines it to a nonzero value. Similarly, the test_for_upstream method only used by SSH doesn't have to be mentioned in the rest of the backends; network Plugs for listening sockets don't have to explicitly null out 'receive' and 'sent', and vice versa for 'accepting', and so on. While I'm at it, I've normalised the declarations so they don't use the unnecessarily verbose 'struct' keyword. Also a handful of them weren't const; now they are.
2020-03-10 21:06:29 +00:00
static const SshChannelVtable ssh1channel_vtable = {
.write = ssh1channel_write,
.write_eof = ssh1channel_write_eof,
.initiate_close = ssh1channel_initiate_close,
.unthrottle = ssh1channel_unthrottle,
.get_conf = ssh1channel_get_conf,
.window_override_removed = ssh1channel_window_override_removed,
/* everything else is NULL */
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
};
static void ssh1_channel_try_eof(struct ssh1_channel *c);
static void ssh1_channel_close_local(struct ssh1_channel *c,
const char *reason);
static void ssh1_channel_destroy(struct ssh1_channel *c);
static void ssh1_channel_check_close(struct ssh1_channel *c);
static int ssh1_channelcmp(void *av, void *bv)
{
const struct ssh1_channel *a = (const struct ssh1_channel *) av;
const struct ssh1_channel *b = (const struct ssh1_channel *) bv;
if (a->localid < b->localid)
Whitespace rationalisation of entire code base. The number of people has been steadily increasing who read our source code with an editor that thinks tab stops are 4 spaces apart, as opposed to the traditional tty-derived 8 that the PuTTY code expects. So I've been wondering for ages about just fixing it, and switching to a spaces-only policy throughout the code. And I recently found out about 'git blame -w', which should make this change not too disruptive for the purposes of source-control archaeology; so perhaps now is the time. While I'm at it, I've also taken the opportunity to remove all the trailing spaces from source lines (on the basis that git dislikes them, and is the only thing that seems to have a strong opinion one way or the other). Apologies to anyone downstream of this code who has complicated patch sets to rebase past this change. I don't intend it to be needed again.
2019-09-08 19:29:00 +00:00
return -1;
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
if (a->localid > b->localid)
Whitespace rationalisation of entire code base. The number of people has been steadily increasing who read our source code with an editor that thinks tab stops are 4 spaces apart, as opposed to the traditional tty-derived 8 that the PuTTY code expects. So I've been wondering for ages about just fixing it, and switching to a spaces-only policy throughout the code. And I recently found out about 'git blame -w', which should make this change not too disruptive for the purposes of source-control archaeology; so perhaps now is the time. While I'm at it, I've also taken the opportunity to remove all the trailing spaces from source lines (on the basis that git dislikes them, and is the only thing that seems to have a strong opinion one way or the other). Apologies to anyone downstream of this code who has complicated patch sets to rebase past this change. I don't intend it to be needed again.
2019-09-08 19:29:00 +00:00
return +1;
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
return 0;
}
static int ssh1_channelfind(void *av, void *bv)
{
const unsigned *a = (const unsigned *) av;
const struct ssh1_channel *b = (const struct ssh1_channel *) bv;
if (*a < b->localid)
Whitespace rationalisation of entire code base. The number of people has been steadily increasing who read our source code with an editor that thinks tab stops are 4 spaces apart, as opposed to the traditional tty-derived 8 that the PuTTY code expects. So I've been wondering for ages about just fixing it, and switching to a spaces-only policy throughout the code. And I recently found out about 'git blame -w', which should make this change not too disruptive for the purposes of source-control archaeology; so perhaps now is the time. While I'm at it, I've also taken the opportunity to remove all the trailing spaces from source lines (on the basis that git dislikes them, and is the only thing that seems to have a strong opinion one way or the other). Apologies to anyone downstream of this code who has complicated patch sets to rebase past this change. I don't intend it to be needed again.
2019-09-08 19:29:00 +00:00
return -1;
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
if (*a > b->localid)
Whitespace rationalisation of entire code base. The number of people has been steadily increasing who read our source code with an editor that thinks tab stops are 4 spaces apart, as opposed to the traditional tty-derived 8 that the PuTTY code expects. So I've been wondering for ages about just fixing it, and switching to a spaces-only policy throughout the code. And I recently found out about 'git blame -w', which should make this change not too disruptive for the purposes of source-control archaeology; so perhaps now is the time. While I'm at it, I've also taken the opportunity to remove all the trailing spaces from source lines (on the basis that git dislikes them, and is the only thing that seems to have a strong opinion one way or the other). Apologies to anyone downstream of this code who has complicated patch sets to rebase past this change. I don't intend it to be needed again.
2019-09-08 19:29:00 +00:00
return +1;
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
return 0;
}
Move client-specific SSH code into new files. This is a major code reorganisation in preparation for making this code base into one that can build an SSH server as well as a client. (Mostly for purposes of using the server as a regression test suite for the client, though I have some other possible uses in mind too. However, it's currently no part of my plan to harden the server to the point where it can sensibly be deployed in a hostile environment.) In this preparatory commit, I've broken up the SSH-2 transport and connection layers, and the SSH-1 connection layer, into multiple source files, with each layer having its own header file containing the shared type definitions. In each case, the new source file contains code that's specific to the client side of the protocol, so that a new file can be swapped in in its place when building the server. Mostly this is just a straightforward moving of code without changing it very much, but there are a couple of actual changes in the process: The parsing of SSH-2 global-request and channel open-messages is now done by a new pair of functions in the client module. For channel opens, I've invented a new union data type to be the return value from that function, representing either failure (plus error message), success (plus Channel instance to manage the new channel), or an instruction to hand the channel over to a sharing downstream (plus a pointer to the downstream in question). Also, the tree234 of remote port forwardings in ssh2connection is now initialised on first use by the client-specific code, so that's where its compare function lives. The shared ssh2connection_free() still takes responsibility for freeing it, but now has to check if it's non-null first. The outer shell of the ssh2_lportfwd_open method, for making a local-to-remote port forwarding, is still centralised in ssh2connection.c, but the part of it that actually constructs the outgoing channel-open message has moved into the client code, because that will have to change depending on whether the channel-open has to have type direct-tcpip or forwarded-tcpip. In the SSH-1 connection layer, half the filter_queue method has moved out into the new client-specific code, but not all of it - bidirectional channel maintenance messages are still handled centrally. One exception is SSH_MSG_PORT_OPEN, which can be sent in both directions, but with subtly different semantics - from server to client, it's referring to a previously established remote forwarding (and must be rejected if there isn't one that matches it), but from client to server it's just a "direct-tcpip" request with no prior context. So that one is in the client-specific module, and when I add the server code it will have its own different handler.
2018-10-20 16:57:37 +00:00
void ssh1_channel_free(struct ssh1_channel *c)
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
{
if (c->chan)
chan_free(c->chan);
sfree(c);
}
PacketProtocolLayer *ssh1_connection_new(
Localise user_input to SSH connection layers. Now that the SSH backend's user_input bufchain is no longer needed for handling userpass input, it doesn't have to be awkwardly shared between all the packet protocol layers any more. So we can turn the want_user_input and got_user_input methods of PacketProtocolLayer into methods of ConnectionLayer, and then only the two connection layers have to bother implementing them, or store a pointer to the bufchain they read from.
2021-09-14 13:00:05 +00:00
Ssh *ssh, Conf *conf, bufchain *user_input, ConnectionLayer **cl_out)
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
{
struct ssh1_connection_state *s = snew(struct ssh1_connection_state);
memset(s, 0, sizeof(*s));
s->ppl.vt = &ssh1_connection_vtable;
s->conf = conf_copy(conf);
s->channels = newtree234(ssh1_channelcmp);
s->x11authtree = newtree234(x11_authcmp);
Localise user_input to SSH connection layers. Now that the SSH backend's user_input bufchain is no longer needed for handling userpass input, it doesn't have to be awkwardly shared between all the packet protocol layers any more. So we can turn the want_user_input and got_user_input methods of PacketProtocolLayer into methods of ConnectionLayer, and then only the two connection layers have to bother implementing them, or store a pointer to the bufchain they read from.
2021-09-14 13:00:05 +00:00
s->user_input = user_input;
Refactor the LogContext type. LogContext is now the owner of the logevent() function that back ends and so forth are constantly calling. Previously, logevent was owned by the Frontend, which would store the message into its list for the GUI Event Log dialog (or print it to standard error, or whatever) and then pass it _back_ to LogContext to write to the currently open log file. Now it's the other way round: LogContext gets the message from the back end first, writes it to its log file if it feels so inclined, and communicates it back to the front end. This means that lots of parts of the back end system no longer need to have a pointer to a full-on Frontend; the only thing they needed it for was logging, so now they just have a LogContext (which many of them had to have anyway, e.g. for logging SSH packets or session traffic). LogContext itself also doesn't get a full Frontend pointer any more: it now talks back to the front end via a little vtable of its own called LogPolicy, which contains the method that passes Event Log entries through, the old askappend() function that decides whether to truncate a pre-existing log file, and an emergency function for printing an especially prominent message if the log file can't be created. One minor nice effect of this is that console and GUI apps can implement that last function subtly differently, so that Unix console apps can write it with a plain \n instead of the \r\n (harmless but inelegant) that the old centralised implementation generated. One other consequence of this is that the LogContext has to be provided to backend_init() so that it's available to backends from the instant of creation, rather than being provided via a separate API call a couple of function calls later, because backends have typically started doing things that need logging (like making network connections) before the call to backend_provide_logctx. Fortunately, there's no case in the whole code base where we don't already have logctx by the time we make a backend (so I don't actually remember why I ever delayed providing one). So that shortens the backend API by one function, which is always nice. While I'm tidying up, I've also moved the printf-style logeventf() and the handy logevent_and_free() into logging.c, instead of having copies of them scattered around other places. This has also let me remove some stub functions from a couple of outlying applications like Pageant. Finally, I've removed the pointless "_tag" at the end of LogContext's official struct name.
2018-10-10 18:26:18 +00:00
/* Need to get the log context for s->cl now, because we won't be
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
* helpfully notified when a copy is written into s->ppl by our
* owner. */
s->cl.vt = &ssh1_connlayer_vtable;
Refactor the LogContext type. LogContext is now the owner of the logevent() function that back ends and so forth are constantly calling. Previously, logevent was owned by the Frontend, which would store the message into its list for the GUI Event Log dialog (or print it to standard error, or whatever) and then pass it _back_ to LogContext to write to the currently open log file. Now it's the other way round: LogContext gets the message from the back end first, writes it to its log file if it feels so inclined, and communicates it back to the front end. This means that lots of parts of the back end system no longer need to have a pointer to a full-on Frontend; the only thing they needed it for was logging, so now they just have a LogContext (which many of them had to have anyway, e.g. for logging SSH packets or session traffic). LogContext itself also doesn't get a full Frontend pointer any more: it now talks back to the front end via a little vtable of its own called LogPolicy, which contains the method that passes Event Log entries through, the old askappend() function that decides whether to truncate a pre-existing log file, and an emergency function for printing an especially prominent message if the log file can't be created. One minor nice effect of this is that console and GUI apps can implement that last function subtly differently, so that Unix console apps can write it with a plain \n instead of the \r\n (harmless but inelegant) that the old centralised implementation generated. One other consequence of this is that the LogContext has to be provided to backend_init() so that it's available to backends from the instant of creation, rather than being provided via a separate API call a couple of function calls later, because backends have typically started doing things that need logging (like making network connections) before the call to backend_provide_logctx. Fortunately, there's no case in the whole code base where we don't already have logctx by the time we make a backend (so I don't actually remember why I ever delayed providing one). So that shortens the backend API by one function, which is always nice. While I'm tidying up, I've also moved the printf-style logeventf() and the handy logevent_and_free() into logging.c, instead of having copies of them scattered around other places. This has also let me remove some stub functions from a couple of outlying applications like Pageant. Finally, I've removed the pointless "_tag" at the end of LogContext's official struct name.
2018-10-10 18:26:18 +00:00
s->cl.logctx = ssh_get_logctx(ssh);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
s->portfwdmgr = portfwdmgr_new(&s->cl);
s->rportfwds = newtree234(ssh1_rportfwd_cmp);
*cl_out = &s->cl;
return &s->ppl;
}
static void ssh1_connection_free(PacketProtocolLayer *ppl)
{
struct ssh1_connection_state *s =
Rename FROMFIELD to 'container_of'. Ian Jackson points out that the Linux kernel has a macro of this name with the same purpose, and suggests that it's a good idea to use the same name as they do, so that at least some people reading one code base might recognise it from the other. I never really thought very hard about what order FROMFIELD's parameters should go in, and therefore I'm pleasantly surprised to find that my order agrees with the kernel's, so I don't have to permute every call site as part of making this change :-)
2018-10-05 22:49:08 +00:00
container_of(ppl, struct ssh1_connection_state, ppl);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
struct X11FakeAuth *auth;
struct ssh1_channel *c;
struct ssh_rportfwd *rpf;
conf_free(s->conf);
while ((c = delpos234(s->channels, 0)) != NULL)
ssh1_channel_free(c);
freetree234(s->channels);
SSH-1: free mainchan_chan on destruction. We went through the tree234 of ordinary channels freeing the thing at the other end of each one, but of course in SSH-1 the main session channel is not stored in that tree due to its totally different shape in the protocol. So naturally I forgot to free _that_ one.
2019-04-20 08:37:54 +00:00
if (s->mainchan_chan)
chan_free(s->mainchan_chan);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
if (s->x11disp)
Whitespace rationalisation of entire code base. The number of people has been steadily increasing who read our source code with an editor that thinks tab stops are 4 spaces apart, as opposed to the traditional tty-derived 8 that the PuTTY code expects. So I've been wondering for ages about just fixing it, and switching to a spaces-only policy throughout the code. And I recently found out about 'git blame -w', which should make this change not too disruptive for the purposes of source-control archaeology; so perhaps now is the time. While I'm at it, I've also taken the opportunity to remove all the trailing spaces from source lines (on the basis that git dislikes them, and is the only thing that seems to have a strong opinion one way or the other). Apologies to anyone downstream of this code who has complicated patch sets to rebase past this change. I don't intend it to be needed again.
2019-09-08 19:29:00 +00:00
x11_free_display(s->x11disp);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
while ((auth = delpos234(s->x11authtree, 0)) != NULL)
x11_free_fake_auth(auth);
freetree234(s->x11authtree);
while ((rpf = delpos234(s->rportfwds, 0)) != NULL)
free_rportfwd(rpf);
freetree234(s->rportfwds);
portfwdmgr_free(s->portfwdmgr);
SSH-1: disable trust sigils after session starts. This exactly replicates the way it's done in SSH-2: at the start of the connection layer we set the trust status to untrusted, and if that reports that it didn't give any indication to the user, we fall back to presenting an interactive anti-spoofing prompt. I don't know how I forgot to do that in SSH-1, and even more, how we haven't noticed for a month. We noticed the same bug in _Rlogin_ within a day of the 0.71 release, after all!
2019-04-20 07:24:16 +00:00
if (s->antispoof_prompt)
free_prompts(s->antispoof_prompt);
Rewrite the SSH-1 main shell session using mainchan. In SSH-1, the channel system isn't rich enough to represent the complicated main shell session, so it's all done with a separate set of custom message types. But PuTTY now abstracts away that difference, by representing both as different implementations of the SshChannel class: ssh1channel is for things that the protocol thinks are 'really' channels, and ssh1mainchan is for the shell session. All the same methods are implemented, but generate different wire messages. This means that the logic to decide _when_ to enable X forwarding, agent forwarding etc is all centralised into mainchan.c, where it doesn't have to be repeated for both protocol versions. It also simplifies the final loop in the connection protocol, which no longer has to contain the code to move data from the user input bufchain to the channel's output; that's now done by the mainchan write method, the same as it is in SSH-2 where mainchan is just like other channels.
2018-09-30 10:22:01 +00:00
delete_callbacks_for_context(s);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
sfree(s);
}
Add an actual SSH server program. This server is NOT SECURE! If anyone is reading this commit message, DO NOT DEPLOY IT IN A HOSTILE-FACING ENVIRONMENT! Its purpose is to speak the server end of everything PuTTY speaks on the client side, so that I can test that I haven't broken PuTTY when I reorganise its code, even things like RSA key exchange or chained auth methods which it's hard to find a server that speaks at all. (For this reason, it's declared with [UT] in the Recipe file, so that it falls into the same category as programs like testbn, which won't be installed by 'make install'.) Working title is 'Uppity', partly for 'Universal PuTTY Protocol Interaction Test Yoke', but mostly because it looks quite like the word 'PuTTY' with part of it reversed. (Apparently 'test yoke' is a very rarely used term meaning something not altogether unlike 'test harness', which is a bit of a stretch, but it'll do.) It doesn't actually _support_ everything I want yet. At the moment, it's a proof of concept only. But it has most of the machinery present, and the parts it's missing - such as chained auth methods - should be easy enough to add because I've built in the required flexibility, in the form of an AuthPolicy object which can request them if it wants to. However, the current AuthPolicy object is entirely trivial, and will let in any user with the password "weasel". (Another way in which this is not a production-ready server is that it also has no interaction with the OS's authentication system. In particular, it will not only let in any user with the same password, but it won't even change uid - it will open shells and forwardings under whatever user id you started it up as.) Currently, the program can only speak the SSH protocol on its standard I/O channels (using the new FdSocket facility), so if you want it to listen on a network port, you'll have to run it from some kind of separate listening program similar to inetd. For my own tests, I'm not even doing that: I'm just having PuTTY spawn it as a local proxy process, which also conveniently eliminates the risk of anyone hostile connecting to it. The bulk of the actual code reorganisation is already done by previous commits, so this change is _mostly_ just dropping in a new set of server-specific source files alongside the client-specific ones I created recently. The remaining changes in the shared SSH code are numerous, but all minor: - a few extra parameters to BPP and PPL constructors (e.g. 'are you in server mode?'), and pass both sets of SSH-1 protocol flags from the login to the connection layer - in server mode, unconditionally send our version string _before_ waiting for the remote one - a new hook in the SSH-1 BPP to handle enabling compression in server mode, where the message exchange works the other way round - new code in the SSH-2 BPP to do _deferred_ compression the other way round (the non-deferred version is still nicely symmetric) - in the SSH-2 transport layer, some adjustments to do key derivation either way round (swapping round the identifying letters in the various hash preimages, and making sure to list the KEXINITs in the right order) - also in the SSH-2 transport layer, an if statement that controls whether we send SERVICE_REQUEST and wait for SERVICE_ACCEPT, or vice versa - new ConnectionLayer methods for opening outgoing channels for X and agent forwardings - new functions in portfwd.c to establish listening sockets suitable for remote-to-local port forwarding (i.e. not under the direction of a Conf the way it's done on the client side).
2018-10-20 21:09:54 +00:00
void ssh1_connection_set_protoflags(PacketProtocolLayer *ppl,
int local, int remote)
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
{
assert(ppl->vt == &ssh1_connection_vtable);
struct ssh1_connection_state *s =
Rename FROMFIELD to 'container_of'. Ian Jackson points out that the Linux kernel has a macro of this name with the same purpose, and suggests that it's a good idea to use the same name as they do, so that at least some people reading one code base might recognise it from the other. I never really thought very hard about what order FROMFIELD's parameters should go in, and therefore I'm pleasantly surprised to find that my order agrees with the kernel's, so I don't have to permute every call site as part of making this change :-)
2018-10-05 22:49:08 +00:00
container_of(ppl, struct ssh1_connection_state, ppl);
Add an actual SSH server program. This server is NOT SECURE! If anyone is reading this commit message, DO NOT DEPLOY IT IN A HOSTILE-FACING ENVIRONMENT! Its purpose is to speak the server end of everything PuTTY speaks on the client side, so that I can test that I haven't broken PuTTY when I reorganise its code, even things like RSA key exchange or chained auth methods which it's hard to find a server that speaks at all. (For this reason, it's declared with [UT] in the Recipe file, so that it falls into the same category as programs like testbn, which won't be installed by 'make install'.) Working title is 'Uppity', partly for 'Universal PuTTY Protocol Interaction Test Yoke', but mostly because it looks quite like the word 'PuTTY' with part of it reversed. (Apparently 'test yoke' is a very rarely used term meaning something not altogether unlike 'test harness', which is a bit of a stretch, but it'll do.) It doesn't actually _support_ everything I want yet. At the moment, it's a proof of concept only. But it has most of the machinery present, and the parts it's missing - such as chained auth methods - should be easy enough to add because I've built in the required flexibility, in the form of an AuthPolicy object which can request them if it wants to. However, the current AuthPolicy object is entirely trivial, and will let in any user with the password "weasel". (Another way in which this is not a production-ready server is that it also has no interaction with the OS's authentication system. In particular, it will not only let in any user with the same password, but it won't even change uid - it will open shells and forwardings under whatever user id you started it up as.) Currently, the program can only speak the SSH protocol on its standard I/O channels (using the new FdSocket facility), so if you want it to listen on a network port, you'll have to run it from some kind of separate listening program similar to inetd. For my own tests, I'm not even doing that: I'm just having PuTTY spawn it as a local proxy process, which also conveniently eliminates the risk of anyone hostile connecting to it. The bulk of the actual code reorganisation is already done by previous commits, so this change is _mostly_ just dropping in a new set of server-specific source files alongside the client-specific ones I created recently. The remaining changes in the shared SSH code are numerous, but all minor: - a few extra parameters to BPP and PPL constructors (e.g. 'are you in server mode?'), and pass both sets of SSH-1 protocol flags from the login to the connection layer - in server mode, unconditionally send our version string _before_ waiting for the remote one - a new hook in the SSH-1 BPP to handle enabling compression in server mode, where the message exchange works the other way round - new code in the SSH-2 BPP to do _deferred_ compression the other way round (the non-deferred version is still nicely symmetric) - in the SSH-2 transport layer, some adjustments to do key derivation either way round (swapping round the identifying letters in the various hash preimages, and making sure to list the KEXINITs in the right order) - also in the SSH-2 transport layer, an if statement that controls whether we send SERVICE_REQUEST and wait for SERVICE_ACCEPT, or vice versa - new ConnectionLayer methods for opening outgoing channels for X and agent forwardings - new functions in portfwd.c to establish listening sockets suitable for remote-to-local port forwarding (i.e. not under the direction of a Conf the way it's done on the client side).
2018-10-20 21:09:54 +00:00
s->local_protoflags = local;
s->remote_protoflags = remote;
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
}
Convert a lot of 'int' variables to 'bool'. My normal habit these days, in new code, is to treat int and bool as _almost_ completely separate types. I'm still willing to use C's implicit test for zero on an integer (e.g. 'if (!blob.len)' is fine, no need to spell it out as blob.len != 0), but generally, if a variable is going to be conceptually a boolean, I like to declare it bool and assign to it using 'true' or 'false' rather than 0 or 1. PuTTY is an exception, because it predates the C99 bool, and I've stuck to its existing coding style even when adding new code to it. But it's been annoying me more and more, so now that I've decided C99 bool is an acceptable thing to require from our toolchain in the first place, here's a quite thorough trawl through the source doing 'boolification'. Many variables and function parameters are now typed as bool rather than int; many assignments of 0 or 1 to those variables are now spelled 'true' or 'false'. I managed this thorough conversion with the help of a custom clang plugin that I wrote to trawl the AST and apply heuristics to point out where things might want changing. So I've even managed to do a decent job on parts of the code I haven't looked at in years! To make the plugin's work easier, I pushed platform front ends generally in the direction of using standard 'bool' in preference to platform-specific boolean types like Windows BOOL or GTK's gboolean; I've left the platform booleans in places they _have_ to be for the platform APIs to work right, but variables only used by my own code have been converted wherever I found them. In a few places there are int values that look very like booleans in _most_ of the places they're used, but have a rarely-used third value, or a distinction between different nonzero values that most users don't care about. In these cases, I've _removed_ uses of 'true' and 'false' for the return values, to emphasise that there's something more subtle going on than a simple boolean answer: - the 'multisel' field in dialog.h's list box structure, for which the GTK front end in particular recognises a difference between 1 and 2 but nearly everything else treats as boolean - the 'urgent' parameter to plug_receive, where 1 vs 2 tells you something about the specific location of the urgent pointer, but most clients only care about 0 vs 'something nonzero' - the return value of wc_match, where -1 indicates a syntax error in the wildcard. - the return values from SSH-1 RSA-key loading functions, which use -1 for 'wrong passphrase' and 0 for all other failures (so any caller which already knows it's not loading an _encrypted private_ key can treat them as boolean) - term->esc_query, and the 'query' parameter in toggle_mode in terminal.c, which _usually_ hold 0 for ESC[123h or 1 for ESC[?123h, but can also hold -1 for some other intervening character that we don't support. In a few places there's an integer that I haven't turned into a bool even though it really _can_ only take values 0 or 1 (and, as above, tried to make the call sites consistent in not calling those values true and false), on the grounds that I thought it would make it more confusing to imply that the 0 value was in some sense 'negative' or bad and the 1 positive or good: - the return value of plug_accepting uses the POSIXish convention of 0=success and nonzero=error; I think if I made it bool then I'd also want to reverse its sense, and that's a job for a separate piece of work. - the 'screen' parameter to lineptr() in terminal.c, where 0 and 1 represent the default and alternate screens. There's no obvious reason why one of those should be considered 'true' or 'positive' or 'success' - they're just indices - so I've left it as int. ssh_scp_recv had particularly confusing semantics for its previous int return value: its call sites used '<= 0' to check for error, but it never actually returned a negative number, just 0 or 1. Now the function and its call sites agree that it's a bool. In a couple of places I've renamed variables called 'ret', because I don't like that name any more - it's unclear whether it means the return value (in preparation) for the _containing_ function or the return value received from a subroutine call, and occasionally I've accidentally used the same variable for both and introduced a bug. So where one of those got in my way, I've renamed it to 'toret' or 'retd' (the latter short for 'returned') in line with my usual modern practice, but I haven't done a thorough job of finding all of them. Finally, one amusing side effect of doing this is that I've had to separate quite a few chained assignments. It used to be perfectly fine to write 'a = b = c = TRUE' when a,b,c were int and TRUE was just a the 'true' defined by stdbool.h, that idiom provokes a warning from gcc: 'suggest parentheses around assignment used as truth value'!
2018-11-02 19:23:19 +00:00
static bool ssh1_connection_filter_queue(struct ssh1_connection_state *s)
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
{
PktIn *pktin;
Move client-specific SSH code into new files. This is a major code reorganisation in preparation for making this code base into one that can build an SSH server as well as a client. (Mostly for purposes of using the server as a regression test suite for the client, though I have some other possible uses in mind too. However, it's currently no part of my plan to harden the server to the point where it can sensibly be deployed in a hostile environment.) In this preparatory commit, I've broken up the SSH-2 transport and connection layers, and the SSH-1 connection layer, into multiple source files, with each layer having its own header file containing the shared type definitions. In each case, the new source file contains code that's specific to the client side of the protocol, so that a new file can be swapped in in its place when building the server. Mostly this is just a straightforward moving of code without changing it very much, but there are a couple of actual changes in the process: The parsing of SSH-2 global-request and channel open-messages is now done by a new pair of functions in the client module. For channel opens, I've invented a new union data type to be the return value from that function, representing either failure (plus error message), success (plus Channel instance to manage the new channel), or an instruction to hand the channel over to a sharing downstream (plus a pointer to the downstream in question). Also, the tree234 of remote port forwardings in ssh2connection is now initialised on first use by the client-specific code, so that's where its compare function lives. The shared ssh2connection_free() still takes responsibility for freeing it, but now has to check if it's non-null first. The outer shell of the ssh2_lportfwd_open method, for making a local-to-remote port forwarding, is still centralised in ssh2connection.c, but the part of it that actually constructs the outgoing channel-open message has moved into the client code, because that will have to change depending on whether the channel-open has to have type direct-tcpip or forwarded-tcpip. In the SSH-1 connection layer, half the filter_queue method has moved out into the new client-specific code, but not all of it - bidirectional channel maintenance messages are still handled centrally. One exception is SSH_MSG_PORT_OPEN, which can be sent in both directions, but with subtly different semantics - from server to client, it's referring to a previously established remote forwarding (and must be rejected if there isn't one that matches it), but from client to server it's just a "direct-tcpip" request with no prior context. So that one is in the client-specific module, and when I add the server code it will have its own different handler.
2018-10-20 16:57:37 +00:00
ptrlen data;
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
struct ssh1_channel *c;
Move client-specific SSH code into new files. This is a major code reorganisation in preparation for making this code base into one that can build an SSH server as well as a client. (Mostly for purposes of using the server as a regression test suite for the client, though I have some other possible uses in mind too. However, it's currently no part of my plan to harden the server to the point where it can sensibly be deployed in a hostile environment.) In this preparatory commit, I've broken up the SSH-2 transport and connection layers, and the SSH-1 connection layer, into multiple source files, with each layer having its own header file containing the shared type definitions. In each case, the new source file contains code that's specific to the client side of the protocol, so that a new file can be swapped in in its place when building the server. Mostly this is just a straightforward moving of code without changing it very much, but there are a couple of actual changes in the process: The parsing of SSH-2 global-request and channel open-messages is now done by a new pair of functions in the client module. For channel opens, I've invented a new union data type to be the return value from that function, representing either failure (plus error message), success (plus Channel instance to manage the new channel), or an instruction to hand the channel over to a sharing downstream (plus a pointer to the downstream in question). Also, the tree234 of remote port forwardings in ssh2connection is now initialised on first use by the client-specific code, so that's where its compare function lives. The shared ssh2connection_free() still takes responsibility for freeing it, but now has to check if it's non-null first. The outer shell of the ssh2_lportfwd_open method, for making a local-to-remote port forwarding, is still centralised in ssh2connection.c, but the part of it that actually constructs the outgoing channel-open message has moved into the client code, because that will have to change depending on whether the channel-open has to have type direct-tcpip or forwarded-tcpip. In the SSH-1 connection layer, half the filter_queue method has moved out into the new client-specific code, but not all of it - bidirectional channel maintenance messages are still handled centrally. One exception is SSH_MSG_PORT_OPEN, which can be sent in both directions, but with subtly different semantics - from server to client, it's referring to a previously established remote forwarding (and must be rejected if there isn't one that matches it), but from client to server it's just a "direct-tcpip" request with no prior context. So that one is in the client-specific module, and when I add the server code it will have its own different handler.
2018-10-20 16:57:37 +00:00
unsigned localid;
Convert a lot of 'int' variables to 'bool'. My normal habit these days, in new code, is to treat int and bool as _almost_ completely separate types. I'm still willing to use C's implicit test for zero on an integer (e.g. 'if (!blob.len)' is fine, no need to spell it out as blob.len != 0), but generally, if a variable is going to be conceptually a boolean, I like to declare it bool and assign to it using 'true' or 'false' rather than 0 or 1. PuTTY is an exception, because it predates the C99 bool, and I've stuck to its existing coding style even when adding new code to it. But it's been annoying me more and more, so now that I've decided C99 bool is an acceptable thing to require from our toolchain in the first place, here's a quite thorough trawl through the source doing 'boolification'. Many variables and function parameters are now typed as bool rather than int; many assignments of 0 or 1 to those variables are now spelled 'true' or 'false'. I managed this thorough conversion with the help of a custom clang plugin that I wrote to trawl the AST and apply heuristics to point out where things might want changing. So I've even managed to do a decent job on parts of the code I haven't looked at in years! To make the plugin's work easier, I pushed platform front ends generally in the direction of using standard 'bool' in preference to platform-specific boolean types like Windows BOOL or GTK's gboolean; I've left the platform booleans in places they _have_ to be for the platform APIs to work right, but variables only used by my own code have been converted wherever I found them. In a few places there are int values that look very like booleans in _most_ of the places they're used, but have a rarely-used third value, or a distinction between different nonzero values that most users don't care about. In these cases, I've _removed_ uses of 'true' and 'false' for the return values, to emphasise that there's something more subtle going on than a simple boolean answer: - the 'multisel' field in dialog.h's list box structure, for which the GTK front end in particular recognises a difference between 1 and 2 but nearly everything else treats as boolean - the 'urgent' parameter to plug_receive, where 1 vs 2 tells you something about the specific location of the urgent pointer, but most clients only care about 0 vs 'something nonzero' - the return value of wc_match, where -1 indicates a syntax error in the wildcard. - the return values from SSH-1 RSA-key loading functions, which use -1 for 'wrong passphrase' and 0 for all other failures (so any caller which already knows it's not loading an _encrypted private_ key can treat them as boolean) - term->esc_query, and the 'query' parameter in toggle_mode in terminal.c, which _usually_ hold 0 for ESC[123h or 1 for ESC[?123h, but can also hold -1 for some other intervening character that we don't support. In a few places there's an integer that I haven't turned into a bool even though it really _can_ only take values 0 or 1 (and, as above, tried to make the call sites consistent in not calling those values true and false), on the grounds that I thought it would make it more confusing to imply that the 0 value was in some sense 'negative' or bad and the 1 positive or good: - the return value of plug_accepting uses the POSIXish convention of 0=success and nonzero=error; I think if I made it bool then I'd also want to reverse its sense, and that's a job for a separate piece of work. - the 'screen' parameter to lineptr() in terminal.c, where 0 and 1 represent the default and alternate screens. There's no obvious reason why one of those should be considered 'true' or 'positive' or 'success' - they're just indices - so I've left it as int. ssh_scp_recv had particularly confusing semantics for its previous int return value: its call sites used '<= 0' to check for error, but it never actually returned a negative number, just 0 or 1. Now the function and its call sites agree that it's a bool. In a couple of places I've renamed variables called 'ret', because I don't like that name any more - it's unclear whether it means the return value (in preparation) for the _containing_ function or the return value received from a subroutine call, and occasionally I've accidentally used the same variable for both and introduced a bug. So where one of those got in my way, I've renamed it to 'toret' or 'retd' (the latter short for 'returned') in line with my usual modern practice, but I haven't done a thorough job of finding all of them. Finally, one amusing side effect of doing this is that I've had to separate quite a few chained assignments. It used to be perfectly fine to write 'a = b = c = TRUE' when a,b,c were int and TRUE was just a the 'true' defined by stdbool.h, that idiom provokes a warning from gcc: 'suggest parentheses around assignment used as truth value'!
2018-11-02 19:23:19 +00:00
bool expect_halfopen;
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
while (1) {
if (ssh1_common_filter_queue(&s->ppl))
Adopt C99 <stdbool.h>'s true/false. This commit includes <stdbool.h> from defs.h and deletes my traditional definitions of TRUE and FALSE, but other than that, it's a 100% mechanical search-and-replace transforming all uses of TRUE and FALSE into the C99-standardised lowercase spellings. No actual types are changed in this commit; that will come next. This is just getting the noise out of the way, so that subsequent commits can have a higher proportion of signal.
2018-10-29 19:50:29 +00:00
return true;
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
if ((pktin = pq_peek(s->ppl.in_pq)) == NULL)
Adopt C99 <stdbool.h>'s true/false. This commit includes <stdbool.h> from defs.h and deletes my traditional definitions of TRUE and FALSE, but other than that, it's a 100% mechanical search-and-replace transforming all uses of TRUE and FALSE into the C99-standardised lowercase spellings. No actual types are changed in this commit; that will come next. This is just getting the noise out of the way, so that subsequent commits can have a higher proportion of signal.
2018-10-29 19:50:29 +00:00
return false;
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
switch (pktin->type) {
case SSH1_MSG_CHANNEL_DATA:
case SSH1_MSG_CHANNEL_OPEN_CONFIRMATION:
case SSH1_MSG_CHANNEL_OPEN_FAILURE:
case SSH1_MSG_CHANNEL_CLOSE:
case SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION:
/*
* Common preliminary code for all the messages from the
* server that cite one of our channel ids: look up that
* channel id, check it exists, and if it's for a sharing
* downstream, pass it on.
*/
localid = get_uint32(pktin);
c = find234(s->channels, &localid, ssh1_channelfind);
expect_halfopen = (
pktin->type == SSH1_MSG_CHANNEL_OPEN_CONFIRMATION ||
pktin->type == SSH1_MSG_CHANNEL_OPEN_FAILURE);
if (!c || c->halfopen != expect_halfopen) {
ssh_remote_error(
s->ppl.ssh, "Received %s for %s channel %u",
ssh1_pkt_type(pktin->type),
!c ? "nonexistent" : c->halfopen ? "half-open" : "open",
localid);
Adopt C99 <stdbool.h>'s true/false. This commit includes <stdbool.h> from defs.h and deletes my traditional definitions of TRUE and FALSE, but other than that, it's a 100% mechanical search-and-replace transforming all uses of TRUE and FALSE into the C99-standardised lowercase spellings. No actual types are changed in this commit; that will come next. This is just getting the noise out of the way, so that subsequent commits can have a higher proportion of signal.
2018-10-29 19:50:29 +00:00
return true;
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
}
Whitespace rationalisation of entire code base. The number of people has been steadily increasing who read our source code with an editor that thinks tab stops are 4 spaces apart, as opposed to the traditional tty-derived 8 that the PuTTY code expects. So I've been wondering for ages about just fixing it, and switching to a spaces-only policy throughout the code. And I recently found out about 'git blame -w', which should make this change not too disruptive for the purposes of source-control archaeology; so perhaps now is the time. While I'm at it, I've also taken the opportunity to remove all the trailing spaces from source lines (on the basis that git dislikes them, and is the only thing that seems to have a strong opinion one way or the other). Apologies to anyone downstream of this code who has complicated patch sets to rebase past this change. I don't intend it to be needed again.
2019-09-08 19:29:00 +00:00
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
switch (pktin->type) {
case SSH1_MSG_CHANNEL_OPEN_CONFIRMATION:
assert(c->halfopen);
c->remoteid = get_uint32(pktin);
Adopt C99 <stdbool.h>'s true/false. This commit includes <stdbool.h> from defs.h and deletes my traditional definitions of TRUE and FALSE, but other than that, it's a 100% mechanical search-and-replace transforming all uses of TRUE and FALSE into the C99-standardised lowercase spellings. No actual types are changed in this commit; that will come next. This is just getting the noise out of the way, so that subsequent commits can have a higher proportion of signal.
2018-10-29 19:50:29 +00:00
c->halfopen = false;
c->throttling_conn = false;
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
chan_open_confirmation(c->chan);
/*
* Now that the channel is fully open, it's possible
* in principle to immediately close it. Check whether
* it wants us to!
*
* This can occur if a local socket error occurred
* between us sending out CHANNEL_OPEN and receiving
* OPEN_CONFIRMATION. If that happens, all we can do
* is immediately initiate close proceedings now that
* we know the server's id to put in the close
* message. We'll have handled that in this code by
* having already turned c->chan into a zombie, so its
* want_close method (which ssh1_channel_check_close
Adopt C99 <stdbool.h>'s true/false. This commit includes <stdbool.h> from defs.h and deletes my traditional definitions of TRUE and FALSE, but other than that, it's a 100% mechanical search-and-replace transforming all uses of TRUE and FALSE into the C99-standardised lowercase spellings. No actual types are changed in this commit; that will come next. This is just getting the noise out of the way, so that subsequent commits can have a higher proportion of signal.
2018-10-29 19:50:29 +00:00
* will consult) will already be returning true.
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
*/
ssh1_channel_check_close(c);
if (c->pending_eof)
ssh1_channel_try_eof(c); /* in case we had a pending EOF */
break;
case SSH1_MSG_CHANNEL_OPEN_FAILURE:
assert(c->halfopen);
chan_open_failed(c->chan, NULL);
chan_free(c->chan);
del234(s->channels, c);
ssh1_channel_free(c);
break;
case SSH1_MSG_CHANNEL_DATA:
data = get_string(pktin);
if (!get_err(pktin)) {
int bufsize = chan_send(
Adopt C99 <stdbool.h>'s true/false. This commit includes <stdbool.h> from defs.h and deletes my traditional definitions of TRUE and FALSE, but other than that, it's a 100% mechanical search-and-replace transforming all uses of TRUE and FALSE into the C99-standardised lowercase spellings. No actual types are changed in this commit; that will come next. This is just getting the noise out of the way, so that subsequent commits can have a higher proportion of signal.
2018-10-29 19:50:29 +00:00
c->chan, false, data.ptr, data.len);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
if (!c->throttling_conn && bufsize > SSH1_BUFFER_LIMIT) {
Adopt C99 <stdbool.h>'s true/false. This commit includes <stdbool.h> from defs.h and deletes my traditional definitions of TRUE and FALSE, but other than that, it's a 100% mechanical search-and-replace transforming all uses of TRUE and FALSE into the C99-standardised lowercase spellings. No actual types are changed in this commit; that will come next. This is just getting the noise out of the way, so that subsequent commits can have a higher proportion of signal.
2018-10-29 19:50:29 +00:00
c->throttling_conn = true;
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
ssh_throttle_conn(s->ppl.ssh, +1);
}
}
break;
case SSH1_MSG_CHANNEL_CLOSE:
if (!(c->closes & CLOSES_RCVD_CLOSE)) {
c->closes |= CLOSES_RCVD_CLOSE;
chan_send_eof(c->chan);
ssh1_channel_check_close(c);
}
break;
case SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION:
if (!(c->closes & CLOSES_RCVD_CLOSECONF)) {
if (!(c->closes & CLOSES_SENT_CLOSE)) {
ssh_remote_error(
s->ppl.ssh,
"Received CHANNEL_CLOSE_CONFIRMATION for channel"
" %u for which we never sent CHANNEL_CLOSE\n",
c->localid);
Adopt C99 <stdbool.h>'s true/false. This commit includes <stdbool.h> from defs.h and deletes my traditional definitions of TRUE and FALSE, but other than that, it's a 100% mechanical search-and-replace transforming all uses of TRUE and FALSE into the C99-standardised lowercase spellings. No actual types are changed in this commit; that will come next. This is just getting the noise out of the way, so that subsequent commits can have a higher proportion of signal.
2018-10-29 19:50:29 +00:00
return true;
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
}
c->closes |= CLOSES_RCVD_CLOSECONF;
ssh1_channel_check_close(c);
}
break;
}
pq_pop(s->ppl.in_pq);
break;
Move client-specific SSH code into new files. This is a major code reorganisation in preparation for making this code base into one that can build an SSH server as well as a client. (Mostly for purposes of using the server as a regression test suite for the client, though I have some other possible uses in mind too. However, it's currently no part of my plan to harden the server to the point where it can sensibly be deployed in a hostile environment.) In this preparatory commit, I've broken up the SSH-2 transport and connection layers, and the SSH-1 connection layer, into multiple source files, with each layer having its own header file containing the shared type definitions. In each case, the new source file contains code that's specific to the client side of the protocol, so that a new file can be swapped in in its place when building the server. Mostly this is just a straightforward moving of code without changing it very much, but there are a couple of actual changes in the process: The parsing of SSH-2 global-request and channel open-messages is now done by a new pair of functions in the client module. For channel opens, I've invented a new union data type to be the return value from that function, representing either failure (plus error message), success (plus Channel instance to manage the new channel), or an instruction to hand the channel over to a sharing downstream (plus a pointer to the downstream in question). Also, the tree234 of remote port forwardings in ssh2connection is now initialised on first use by the client-specific code, so that's where its compare function lives. The shared ssh2connection_free() still takes responsibility for freeing it, but now has to check if it's non-null first. The outer shell of the ssh2_lportfwd_open method, for making a local-to-remote port forwarding, is still centralised in ssh2connection.c, but the part of it that actually constructs the outgoing channel-open message has moved into the client code, because that will have to change depending on whether the channel-open has to have type direct-tcpip or forwarded-tcpip. In the SSH-1 connection layer, half the filter_queue method has moved out into the new client-specific code, but not all of it - bidirectional channel maintenance messages are still handled centrally. One exception is SSH_MSG_PORT_OPEN, which can be sent in both directions, but with subtly different semantics - from server to client, it's referring to a previously established remote forwarding (and must be rejected if there isn't one that matches it), but from client to server it's just a "direct-tcpip" request with no prior context. So that one is in the client-specific module, and when I add the server code it will have its own different handler.
2018-10-20 16:57:37 +00:00
default:
if (ssh1_handle_direction_specific_packet(s, pktin)) {
pq_pop(s->ppl.in_pq);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
if (ssh1_check_termination(s))
Adopt C99 <stdbool.h>'s true/false. This commit includes <stdbool.h> from defs.h and deletes my traditional definitions of TRUE and FALSE, but other than that, it's a 100% mechanical search-and-replace transforming all uses of TRUE and FALSE into the C99-standardised lowercase spellings. No actual types are changed in this commit; that will come next. This is just getting the noise out of the way, so that subsequent commits can have a higher proportion of signal.
2018-10-29 19:50:29 +00:00
return true;
Move client-specific SSH code into new files. This is a major code reorganisation in preparation for making this code base into one that can build an SSH server as well as a client. (Mostly for purposes of using the server as a regression test suite for the client, though I have some other possible uses in mind too. However, it's currently no part of my plan to harden the server to the point where it can sensibly be deployed in a hostile environment.) In this preparatory commit, I've broken up the SSH-2 transport and connection layers, and the SSH-1 connection layer, into multiple source files, with each layer having its own header file containing the shared type definitions. In each case, the new source file contains code that's specific to the client side of the protocol, so that a new file can be swapped in in its place when building the server. Mostly this is just a straightforward moving of code without changing it very much, but there are a couple of actual changes in the process: The parsing of SSH-2 global-request and channel open-messages is now done by a new pair of functions in the client module. For channel opens, I've invented a new union data type to be the return value from that function, representing either failure (plus error message), success (plus Channel instance to manage the new channel), or an instruction to hand the channel over to a sharing downstream (plus a pointer to the downstream in question). Also, the tree234 of remote port forwardings in ssh2connection is now initialised on first use by the client-specific code, so that's where its compare function lives. The shared ssh2connection_free() still takes responsibility for freeing it, but now has to check if it's non-null first. The outer shell of the ssh2_lportfwd_open method, for making a local-to-remote port forwarding, is still centralised in ssh2connection.c, but the part of it that actually constructs the outgoing channel-open message has moved into the client code, because that will have to change depending on whether the channel-open has to have type direct-tcpip or forwarded-tcpip. In the SSH-1 connection layer, half the filter_queue method has moved out into the new client-specific code, but not all of it - bidirectional channel maintenance messages are still handled centrally. One exception is SSH_MSG_PORT_OPEN, which can be sent in both directions, but with subtly different semantics - from server to client, it's referring to a previously established remote forwarding (and must be rejected if there isn't one that matches it), but from client to server it's just a "direct-tcpip" request with no prior context. So that one is in the client-specific module, and when I add the server code it will have its own different handler.
2018-10-20 16:57:37 +00:00
} else {
Adopt C99 <stdbool.h>'s true/false. This commit includes <stdbool.h> from defs.h and deletes my traditional definitions of TRUE and FALSE, but other than that, it's a 100% mechanical search-and-replace transforming all uses of TRUE and FALSE into the C99-standardised lowercase spellings. No actual types are changed in this commit; that will come next. This is just getting the noise out of the way, so that subsequent commits can have a higher proportion of signal.
2018-10-29 19:50:29 +00:00
return false;
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
}
}
}
}
static PktIn *ssh1_connection_pop(struct ssh1_connection_state *s)
{
ssh1_connection_filter_queue(s);
return pq_pop(s->ppl.in_pq);
}
static void ssh1_connection_process_queue(PacketProtocolLayer *ppl)
{
struct ssh1_connection_state *s =
Rename FROMFIELD to 'container_of'. Ian Jackson points out that the Linux kernel has a macro of this name with the same purpose, and suggests that it's a good idea to use the same name as they do, so that at least some people reading one code base might recognise it from the other. I never really thought very hard about what order FROMFIELD's parameters should go in, and therefore I'm pleasantly surprised to find that my order agrees with the kernel's, so I don't have to permute every call site as part of making this change :-)
2018-10-05 22:49:08 +00:00
container_of(ppl, struct ssh1_connection_state, ppl);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
PktIn *pktin;
if (ssh1_connection_filter_queue(s)) /* no matter why we were called */
return;
crBegin(s->crState);
SSH-1: disable trust sigils after session starts. This exactly replicates the way it's done in SSH-2: at the start of the connection layer we set the trust status to untrusted, and if that reports that it didn't give any indication to the user, we fall back to presenting an interactive anti-spoofing prompt. I don't know how I forgot to do that in SSH-1, and even more, how we haven't noticed for a month. We noticed the same bug in _Rlogin_ within a day of the 0.71 release, after all!
2019-04-20 07:24:16 +00:00
/*
* Signal the seat that authentication is done, so that it can
* deploy spoofing defences. If it doesn't have any, deploy our
* own fallback one.
*
* We do this here rather than at the end of userauth, because we
* might not have gone through userauth at all (if we're a
* connection-sharing downstream).
*/
if (ssh1_connection_need_antispoof_prompt(s)) {
Complete rework of terminal userpass input system. The system for handling seat_get_userpass_input has always been structured differently between GUI PuTTY and CLI tools like Plink. In the CLI tools, password input is read directly from the OS terminal/console device by console_get_userpass_input; this means that you need to ensure the same terminal input data _hasn't_ already been consumed by the main event loop and sent on to the backend. This is achieved by the backend_sendok() method, which tells the event loop when the backend has finished issuing password prompts, and hence, when it's safe to start passing standard input to backend_send(). But in the GUI tools, input generated by the terminal window has always been sent straight to backend_send(), regardless of whether backend_sendok() says it wants it. So the terminal-based implementation of username and password prompts has to work by consuming input data that had _already_ been passed to the backend - hence, any backend that needs to do that must keep its input on a bufchain, and pass that bufchain to seat_get_userpass_input. It's awkward that these two totally different systems coexist in the first place. And now that SSH proxying needs to present interactive prompts of its own, it's clear which one should win: the CLI style is the Right Thing. So this change reworks the GUI side of the mechanism to be more similar: terminal data now goes into a queue in the Ldisc, and is not sent on to the backend until the backend says it's ready for it via backend_sendok(). So terminal-based userpass prompts can now consume data directly from that queue during the connection setup stage. As a result, the 'bufchain *' parameter has vanished from all the userpass_input functions (both the official implementations of the Seat trait method, and term_get_userpass_input() to which some of those implementations delegate). The only function that actually used that bufchain, namely term_get_userpass_input(), now instead reads from the ldisc's input queue via a couple of new Ldisc functions. (Not _trivial_ functions, since input buffered by Ldisc can be a mixture of raw bytes and session specials like SS_EOL! The input queue inside Ldisc is a bufchain containing a fiddly binary encoding that can represent an arbitrary interleaving of those things.) This greatly simplifies the calls to seat_get_userpass_input in backends, which now don't have to mess about with passing their own user_input bufchain around, or toggling their want_user_input flag back and forth to request data to put on to that bufchain. But the flip side is that now there has to be some _other_ method for notifying the terminal when there's more input to be consumed during an interactive prompt, and for notifying the backend when prompt input has finished so that it can proceed to the next stage of the protocol. This is done by a pair of extra callbacks: when more data is put on to Ldisc's input queue, it triggers a call to term_get_userpass_input, and when term_get_userpass_input finishes, it calls a callback function provided in the prompts_t. Therefore, any use of a prompts_t which *might* be asynchronous must fill in the latter callback when setting up the prompts_t. In SSH, the callback is centralised into a common PPL helper function, which reinvokes the same PPL's process_queue coroutine; in rlogin we have to set it up ourselves. I'm sorry for this large and sprawling patch: I tried fairly hard to break it up into individually comprehensible sub-patches, but I just couldn't tease out any part of it that would stand sensibly alone.
2021-09-14 10:57:21 +00:00
s->antispoof_prompt = ssh_ppl_new_prompts(&s->ppl);
SSH-1: disable trust sigils after session starts. This exactly replicates the way it's done in SSH-2: at the start of the connection layer we set the trust status to untrusted, and if that reports that it didn't give any indication to the user, we fall back to presenting an interactive anti-spoofing prompt. I don't know how I forgot to do that in SSH-1, and even more, how we haven't noticed for a month. We noticed the same bug in _Rlogin_ within a day of the 0.71 release, after all!
2019-04-20 07:24:16 +00:00
s->antispoof_prompt->to_server = true;
s->antispoof_prompt->from_server = false;
s->antispoof_prompt->name = dupstr("Authentication successful");
add_prompt(
s->antispoof_prompt,
dupstr("Access granted. Press Return to begin session. "), false);
s->antispoof_ret = seat_get_userpass_input(
Framework for announcing which Interactor is talking. All this Interactor business has been gradually working towards being able to inform the user _which_ network connection is currently presenting them with a password prompt (or whatever), in situations where more than one of them might be, such as an SSH connection being used as a proxy for another SSH connection when neither one has one-touch login configured. At some point, we have to arrange that any attempt to do a user interaction during connection setup - be it a password prompt, a host key confirmation dialog, or just displaying an SSH login banner - makes it clear which host it's come from. That's going to mean calling some kind of announcement function before doing any of those things. But there are several of those functions in the Seat API, and calls to them are scattered far and wide across the SSH backend. (And not even just there - the Rlogin backend also uses seat_get_userpass_input). How can we possibly make sure we don't forget a vital call site on some obscure little-tested code path, and leave the user confused in just that one case which nobody might notice for years? Today I thought of a trick to solve that problem. We can use the C type system to enforce it for us! The plan is: we invent a new struct type which contains nothing but a 'Seat *'. Then, for every Seat method which does a thing that ought to be clearly identified as relating to a particular Interactor, we adjust the API for that function to take the new struct type where it previously took a plain 'Seat *'. Or rather - doing less violence to the existing code - we only need to adjust the API of the dispatch functions inline in putty.h. How does that help? Because the way you _get_ one of these struct-wrapped Seat pointers is by calling interactor_announce() on your Interactor, which will in turn call interactor_get_seat(), and wrap the returned pointer into one of these structs. The effect is that whenever the SSH (or Rlogin) code wants to call one of those particular Seat methods, it _has_ to call interactor_announce() just beforehand, which (once I finish all of this) will make sure the user is aware of who is presenting the prompt or banner or whatever. And you can't forget to call it, because if you don't call it, then you just don't have a struct of the right type to give to the Seat method you wanted to call! (Of course, there's nothing stopping code from _deliberately_ taking a Seat * it already has and wrapping it into the new struct. In fact SshProxy has to do that, in order to forward these requests up the chain of Seats. But the point is that you can't do it _by accident_, just by forgetting to make a vital function call - when you do that, you _know_ you're doing it on purpose.) No functional change: the new interactor_announce() function exists, and the type-system trick ensures it's called in all the right places, but it doesn't actually _do_ anything yet.
2021-10-30 17:05:36 +00:00
ppl_get_iseat(&s->ppl), s->antispoof_prompt);
Richer data type for interactive prompt results. All the seat functions that request an interactive prompt of some kind to the user - both the main seat_get_userpass_input and the various confirmation dialogs for things like host keys - were using a simple int return value, with the general semantics of 0 = "fail", 1 = "proceed" (and in the case of seat_get_userpass_input, answers to the prompts were provided), and -1 = "request in progress, wait for a callback". In this commit I change all those functions' return types to a new struct called SeatPromptResult, whose primary field is an enum replacing those simple integer values. The main purpose is that the enum has not three but _four_ values: the "fail" result has been split into 'user abort' and 'software abort'. The distinction is that a user abort occurs as a result of an interactive UI action, such as the user clicking 'cancel' in a dialog box or hitting ^D or ^C at a terminal password prompt - and therefore, there's no need to display an error message telling the user that the interactive operation has failed, because the user already knows, because they _did_ it. 'Software abort' is from any other cause, where PuTTY is the first to know there was a problem, and has to tell the user. We already had this 'user abort' vs 'software abort' distinction in other parts of the code - the SSH backend has separate termination functions which protocol layers can call. But we assumed that any failure from an interactive prompt request fell into the 'user abort' category, which is not true. A couple of examples: if you configure a host key fingerprint in your saved session via the SSH > Host keys pane, and the server presents a host key that doesn't match it, then verify_ssh_host_key would report that the user had aborted the connection, and feel no need to tell the user what had gone wrong! Similarly, if a password provided on the command line was not accepted, then (after I fixed the semantics of that in the previous commit) the same wrong handling would occur. So now, those Seat prompt functions too can communicate whether the user or the software originated a connection abort. And in the latter case, we also provide an error message to present to the user. Result: in those two example cases (and others), error messages should no longer go missing. Implementation note: to avoid the hassle of having the error message in a SeatPromptResult being a dynamically allocated string (and hence, every recipient of one must always check whether it's non-NULL and free it on every exit path, plus being careful about copying the struct around), I've instead arranged that the structure contains a function pointer and a couple of parameters, so that the string form of the message can be constructed on demand. That way, the only users who need to free it are the ones who actually _asked_ for it in the first place, which is a much smaller set. (This is one of the rare occasions that I regret not having C++'s extra features available in this code base - a unique_ptr or shared_ptr to a string would have been just the thing here, and the compiler would have done all the hard work for me of remembering where to insert the frees!)
2021-12-28 17:52:00 +00:00
while (s->antispoof_ret.kind == SPRK_INCOMPLETE) {
SSH-1: disable trust sigils after session starts. This exactly replicates the way it's done in SSH-2: at the start of the connection layer we set the trust status to untrusted, and if that reports that it didn't give any indication to the user, we fall back to presenting an interactive anti-spoofing prompt. I don't know how I forgot to do that in SSH-1, and even more, how we haven't noticed for a month. We noticed the same bug in _Rlogin_ within a day of the 0.71 release, after all!
2019-04-20 07:24:16 +00:00
crReturnV;
Complete rework of terminal userpass input system. The system for handling seat_get_userpass_input has always been structured differently between GUI PuTTY and CLI tools like Plink. In the CLI tools, password input is read directly from the OS terminal/console device by console_get_userpass_input; this means that you need to ensure the same terminal input data _hasn't_ already been consumed by the main event loop and sent on to the backend. This is achieved by the backend_sendok() method, which tells the event loop when the backend has finished issuing password prompts, and hence, when it's safe to start passing standard input to backend_send(). But in the GUI tools, input generated by the terminal window has always been sent straight to backend_send(), regardless of whether backend_sendok() says it wants it. So the terminal-based implementation of username and password prompts has to work by consuming input data that had _already_ been passed to the backend - hence, any backend that needs to do that must keep its input on a bufchain, and pass that bufchain to seat_get_userpass_input. It's awkward that these two totally different systems coexist in the first place. And now that SSH proxying needs to present interactive prompts of its own, it's clear which one should win: the CLI style is the Right Thing. So this change reworks the GUI side of the mechanism to be more similar: terminal data now goes into a queue in the Ldisc, and is not sent on to the backend until the backend says it's ready for it via backend_sendok(). So terminal-based userpass prompts can now consume data directly from that queue during the connection setup stage. As a result, the 'bufchain *' parameter has vanished from all the userpass_input functions (both the official implementations of the Seat trait method, and term_get_userpass_input() to which some of those implementations delegate). The only function that actually used that bufchain, namely term_get_userpass_input(), now instead reads from the ldisc's input queue via a couple of new Ldisc functions. (Not _trivial_ functions, since input buffered by Ldisc can be a mixture of raw bytes and session specials like SS_EOL! The input queue inside Ldisc is a bufchain containing a fiddly binary encoding that can represent an arbitrary interleaving of those things.) This greatly simplifies the calls to seat_get_userpass_input in backends, which now don't have to mess about with passing their own user_input bufchain around, or toggling their want_user_input flag back and forth to request data to put on to that bufchain. But the flip side is that now there has to be some _other_ method for notifying the terminal when there's more input to be consumed during an interactive prompt, and for notifying the backend when prompt input has finished so that it can proceed to the next stage of the protocol. This is done by a pair of extra callbacks: when more data is put on to Ldisc's input queue, it triggers a call to term_get_userpass_input, and when term_get_userpass_input finishes, it calls a callback function provided in the prompts_t. Therefore, any use of a prompts_t which *might* be asynchronous must fill in the latter callback when setting up the prompts_t. In SSH, the callback is centralised into a common PPL helper function, which reinvokes the same PPL's process_queue coroutine; in rlogin we have to set it up ourselves. I'm sorry for this large and sprawling patch: I tried fairly hard to break it up into individually comprehensible sub-patches, but I just couldn't tease out any part of it that would stand sensibly alone.
2021-09-14 10:57:21 +00:00
s->antispoof_ret = seat_get_userpass_input(
Framework for announcing which Interactor is talking. All this Interactor business has been gradually working towards being able to inform the user _which_ network connection is currently presenting them with a password prompt (or whatever), in situations where more than one of them might be, such as an SSH connection being used as a proxy for another SSH connection when neither one has one-touch login configured. At some point, we have to arrange that any attempt to do a user interaction during connection setup - be it a password prompt, a host key confirmation dialog, or just displaying an SSH login banner - makes it clear which host it's come from. That's going to mean calling some kind of announcement function before doing any of those things. But there are several of those functions in the Seat API, and calls to them are scattered far and wide across the SSH backend. (And not even just there - the Rlogin backend also uses seat_get_userpass_input). How can we possibly make sure we don't forget a vital call site on some obscure little-tested code path, and leave the user confused in just that one case which nobody might notice for years? Today I thought of a trick to solve that problem. We can use the C type system to enforce it for us! The plan is: we invent a new struct type which contains nothing but a 'Seat *'. Then, for every Seat method which does a thing that ought to be clearly identified as relating to a particular Interactor, we adjust the API for that function to take the new struct type where it previously took a plain 'Seat *'. Or rather - doing less violence to the existing code - we only need to adjust the API of the dispatch functions inline in putty.h. How does that help? Because the way you _get_ one of these struct-wrapped Seat pointers is by calling interactor_announce() on your Interactor, which will in turn call interactor_get_seat(), and wrap the returned pointer into one of these structs. The effect is that whenever the SSH (or Rlogin) code wants to call one of those particular Seat methods, it _has_ to call interactor_announce() just beforehand, which (once I finish all of this) will make sure the user is aware of who is presenting the prompt or banner or whatever. And you can't forget to call it, because if you don't call it, then you just don't have a struct of the right type to give to the Seat method you wanted to call! (Of course, there's nothing stopping code from _deliberately_ taking a Seat * it already has and wrapping it into the new struct. In fact SshProxy has to do that, in order to forward these requests up the chain of Seats. But the point is that you can't do it _by accident_, just by forgetting to make a vital function call - when you do that, you _know_ you're doing it on purpose.) No functional change: the new interactor_announce() function exists, and the type-system trick ensures it's called in all the right places, but it doesn't actually _do_ anything yet.
2021-10-30 17:05:36 +00:00
ppl_get_iseat(&s->ppl), s->antispoof_prompt);
SSH-1: disable trust sigils after session starts. This exactly replicates the way it's done in SSH-2: at the start of the connection layer we set the trust status to untrusted, and if that reports that it didn't give any indication to the user, we fall back to presenting an interactive anti-spoofing prompt. I don't know how I forgot to do that in SSH-1, and even more, how we haven't noticed for a month. We noticed the same bug in _Rlogin_ within a day of the 0.71 release, after all!
2019-04-20 07:24:16 +00:00
}
free_prompts(s->antispoof_prompt);
s->antispoof_prompt = NULL;
}
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
portfwdmgr_config(s->portfwdmgr, s->conf);
Adopt C99 <stdbool.h>'s true/false. This commit includes <stdbool.h> from defs.h and deletes my traditional definitions of TRUE and FALSE, but other than that, it's a 100% mechanical search-and-replace transforming all uses of TRUE and FALSE into the C99-standardised lowercase spellings. No actual types are changed in this commit; that will come next. This is just getting the noise out of the way, so that subsequent commits can have a higher proportion of signal.
2018-10-29 19:50:29 +00:00
s->portfwdmgr_configured = true;
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
Move client-specific SSH code into new files. This is a major code reorganisation in preparation for making this code base into one that can build an SSH server as well as a client. (Mostly for purposes of using the server as a regression test suite for the client, though I have some other possible uses in mind too. However, it's currently no part of my plan to harden the server to the point where it can sensibly be deployed in a hostile environment.) In this preparatory commit, I've broken up the SSH-2 transport and connection layers, and the SSH-1 connection layer, into multiple source files, with each layer having its own header file containing the shared type definitions. In each case, the new source file contains code that's specific to the client side of the protocol, so that a new file can be swapped in in its place when building the server. Mostly this is just a straightforward moving of code without changing it very much, but there are a couple of actual changes in the process: The parsing of SSH-2 global-request and channel open-messages is now done by a new pair of functions in the client module. For channel opens, I've invented a new union data type to be the return value from that function, representing either failure (plus error message), success (plus Channel instance to manage the new channel), or an instruction to hand the channel over to a sharing downstream (plus a pointer to the downstream in question). Also, the tree234 of remote port forwardings in ssh2connection is now initialised on first use by the client-specific code, so that's where its compare function lives. The shared ssh2connection_free() still takes responsibility for freeing it, but now has to check if it's non-null first. The outer shell of the ssh2_lportfwd_open method, for making a local-to-remote port forwarding, is still centralised in ssh2connection.c, but the part of it that actually constructs the outgoing channel-open message has moved into the client code, because that will have to change depending on whether the channel-open has to have type direct-tcpip or forwarded-tcpip. In the SSH-1 connection layer, half the filter_queue method has moved out into the new client-specific code, but not all of it - bidirectional channel maintenance messages are still handled centrally. One exception is SSH_MSG_PORT_OPEN, which can be sent in both directions, but with subtly different semantics - from server to client, it's referring to a previously established remote forwarding (and must be rejected if there isn't one that matches it), but from client to server it's just a "direct-tcpip" request with no prior context. So that one is in the client-specific module, and when I add the server code it will have its own different handler.
2018-10-20 16:57:37 +00:00
while (!s->finished_setup) {
ssh1_connection_direction_specific_setup(s);
crReturnV;
}
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
while (1) {
Whitespace rationalisation of entire code base. The number of people has been steadily increasing who read our source code with an editor that thinks tab stops are 4 spaces apart, as opposed to the traditional tty-derived 8 that the PuTTY code expects. So I've been wondering for ages about just fixing it, and switching to a spaces-only policy throughout the code. And I recently found out about 'git blame -w', which should make this change not too disruptive for the purposes of source-control archaeology; so perhaps now is the time. While I'm at it, I've also taken the opportunity to remove all the trailing spaces from source lines (on the basis that git dislikes them, and is the only thing that seems to have a strong opinion one way or the other). Apologies to anyone downstream of this code who has complicated patch sets to rebase past this change. I don't intend it to be needed again.
2019-09-08 19:29:00 +00:00
/*
* By this point, most incoming packets are already being
* handled by filter_queue, and we need only pay attention to
* the unusual ones.
*/
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
Whitespace rationalisation of entire code base. The number of people has been steadily increasing who read our source code with an editor that thinks tab stops are 4 spaces apart, as opposed to the traditional tty-derived 8 that the PuTTY code expects. So I've been wondering for ages about just fixing it, and switching to a spaces-only policy throughout the code. And I recently found out about 'git blame -w', which should make this change not too disruptive for the purposes of source-control archaeology; so perhaps now is the time. While I'm at it, I've also taken the opportunity to remove all the trailing spaces from source lines (on the basis that git dislikes them, and is the only thing that seems to have a strong opinion one way or the other). Apologies to anyone downstream of this code who has complicated patch sets to rebase past this change. I don't intend it to be needed again.
2019-09-08 19:29:00 +00:00
if ((pktin = ssh1_connection_pop(s)) != NULL) {
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
ssh_proto_error(s->ppl.ssh, "Unexpected packet received, "
"type %d (%s)", pktin->type,
ssh1_pkt_type(pktin->type));
return;
Whitespace rationalisation of entire code base. The number of people has been steadily increasing who read our source code with an editor that thinks tab stops are 4 spaces apart, as opposed to the traditional tty-derived 8 that the PuTTY code expects. So I've been wondering for ages about just fixing it, and switching to a spaces-only policy throughout the code. And I recently found out about 'git blame -w', which should make this change not too disruptive for the purposes of source-control archaeology; so perhaps now is the time. While I'm at it, I've also taken the opportunity to remove all the trailing spaces from source lines (on the basis that git dislikes them, and is the only thing that seems to have a strong opinion one way or the other). Apologies to anyone downstream of this code who has complicated patch sets to rebase past this change. I don't intend it to be needed again.
2019-09-08 19:29:00 +00:00
}
crReturnV;
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
}
crFinishV;
}
static void ssh1_channel_check_close(struct ssh1_channel *c)
{
struct ssh1_connection_state *s = c->connlayer;
PktOut *pktout;
if (c->halfopen) {
/*
* If we've sent out our own CHANNEL_OPEN but not yet seen
* either OPEN_CONFIRMATION or OPEN_FAILURE in response, then
* it's too early to be sending close messages of any kind.
*/
return;
}
if ((!((CLOSES_SENT_CLOSE | CLOSES_RCVD_CLOSE) & ~c->closes) ||
chan_want_close(c->chan, (c->closes & CLOSES_SENT_CLOSE),
(c->closes & CLOSES_RCVD_CLOSE))) &&
Whitespace rationalisation of entire code base. The number of people has been steadily increasing who read our source code with an editor that thinks tab stops are 4 spaces apart, as opposed to the traditional tty-derived 8 that the PuTTY code expects. So I've been wondering for ages about just fixing it, and switching to a spaces-only policy throughout the code. And I recently found out about 'git blame -w', which should make this change not too disruptive for the purposes of source-control archaeology; so perhaps now is the time. While I'm at it, I've also taken the opportunity to remove all the trailing spaces from source lines (on the basis that git dislikes them, and is the only thing that seems to have a strong opinion one way or the other). Apologies to anyone downstream of this code who has complicated patch sets to rebase past this change. I don't intend it to be needed again.
2019-09-08 19:29:00 +00:00
!(c->closes & CLOSES_SENT_CLOSECONF)) {
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
/*
* We have both sent and received CLOSE (or the channel type
* doesn't need us to), which means the channel is in final
* wind-up. Send CLOSE and/or CLOSE_CONFIRMATION, whichever we
* haven't sent yet.
*/
if (!(c->closes & CLOSES_SENT_CLOSE)) {
pktout = ssh_bpp_new_pktout(s->ppl.bpp, SSH1_MSG_CHANNEL_CLOSE);
put_uint32(pktout, c->remoteid);
pq_push(s->ppl.out_pq, pktout);
c->closes |= CLOSES_SENT_CLOSE;
}
if (c->closes & CLOSES_RCVD_CLOSE) {
pktout = ssh_bpp_new_pktout(
s->ppl.bpp, SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION);
put_uint32(pktout, c->remoteid);
pq_push(s->ppl.out_pq, pktout);
c->closes |= CLOSES_SENT_CLOSECONF;
}
}
if (!((CLOSES_SENT_CLOSECONF | CLOSES_RCVD_CLOSECONF) & ~c->closes)) {
/*
* We have both sent and received CLOSE_CONFIRMATION, which
* means we're completely done with the channel.
*/
ssh1_channel_destroy(c);
}
}
static void ssh1_channel_try_eof(struct ssh1_channel *c)
{
struct ssh1_connection_state *s = c->connlayer;
PktOut *pktout;
assert(c->pending_eof); /* precondition for calling us */
if (c->halfopen)
return; /* can't close: not even opened yet */
Adopt C99 <stdbool.h>'s true/false. This commit includes <stdbool.h> from defs.h and deletes my traditional definitions of TRUE and FALSE, but other than that, it's a 100% mechanical search-and-replace transforming all uses of TRUE and FALSE into the C99-standardised lowercase spellings. No actual types are changed in this commit; that will come next. This is just getting the noise out of the way, so that subsequent commits can have a higher proportion of signal.
2018-10-29 19:50:29 +00:00
c->pending_eof = false; /* we're about to send it */
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
pktout = ssh_bpp_new_pktout(s->ppl.bpp, SSH1_MSG_CHANNEL_CLOSE);
put_uint32(pktout, c->remoteid);
pq_push(s->ppl.out_pq, pktout);
c->closes |= CLOSES_SENT_CLOSE;
ssh1_channel_check_close(c);
}
/*
* Close any local socket and free any local resources associated with
* a channel. This converts the channel into a zombie.
*/
static void ssh1_channel_close_local(struct ssh1_channel *c,
const char *reason)
{
struct ssh1_connection_state *s = c->connlayer;
PacketProtocolLayer *ppl = &s->ppl; /* for ppl_logevent */
Fix a memory leak in ssh1_channel_close_local. Leak Sanitiser was kind enough to point this out to me during testing of the port forwarding rework: chan_log_close_msg() returns a dynamically allocated char *, which the caller is supposed to free.
2020-01-27 19:40:58 +00:00
char *msg = chan_log_close_msg(c->chan);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
Fix a memory leak in ssh1_channel_close_local. Leak Sanitiser was kind enough to point this out to me during testing of the port forwarding rework: chan_log_close_msg() returns a dynamically allocated char *, which the caller is supposed to free.
2020-01-27 19:40:58 +00:00
if (msg != NULL) {
Start using C99 variadic macros. In the past, I've had a lot of macros which you call with double parentheses, along the lines of debug(("format string", params)), so that the inner parens protect the commas and permit the macro to treat the whole printf-style argument list as one macro argument. That's all very well, but it's a bit inconvenient (it doesn't leave you any way to implement such a macro by prepending another argument to the list), and now this code base's rules allow C99isms, I can switch all those macros to using a single pair of parens, using the C99 ability to say '...' in the parameter list of the #define and get at the corresponding suffix of the arguments as __VA_ARGS__. So I'm doing it. I've made the following printf-style macros variadic: bpp_logevent, ppl_logevent, ppl_printf and debug. While I'm here, I've also fixed up a collection of conditioned-out calls to debug() in the Windows front end which were clearly expecting a macro with a different calling syntax, because they had an integer parameter first. If I ever have a need to condition those back in, they should actually work now.
2018-12-08 20:32:31 +00:00
ppl_logevent("%s%s%s", msg, reason ? " " : "", reason ? reason : "");
Fix a memory leak in ssh1_channel_close_local. Leak Sanitiser was kind enough to point this out to me during testing of the port forwarding rework: chan_log_close_msg() returns a dynamically allocated char *, which the caller is supposed to free.
2020-01-27 19:40:58 +00:00
sfree(msg);
}
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
chan_free(c->chan);
c->chan = zombiechan_new();
}
static void ssh1_check_termination_callback(void *vctx)
{
struct ssh1_connection_state *s = (struct ssh1_connection_state *)vctx;
ssh1_check_termination(s);
}
static void ssh1_channel_destroy(struct ssh1_channel *c)
{
struct ssh1_connection_state *s = c->connlayer;
ssh1_channel_close_local(c, NULL);
del234(s->channels, c);
ssh1_channel_free(c);
/*
* If that was the last channel left open, we might need to
* terminate. But we'll be a bit cautious, by doing that in a
* toplevel callback, just in case anything on the current call
* stack objects to this entire PPL being freed.
*/
queue_toplevel_callback(ssh1_check_termination_callback, s);
}
Convert a lot of 'int' variables to 'bool'. My normal habit these days, in new code, is to treat int and bool as _almost_ completely separate types. I'm still willing to use C's implicit test for zero on an integer (e.g. 'if (!blob.len)' is fine, no need to spell it out as blob.len != 0), but generally, if a variable is going to be conceptually a boolean, I like to declare it bool and assign to it using 'true' or 'false' rather than 0 or 1. PuTTY is an exception, because it predates the C99 bool, and I've stuck to its existing coding style even when adding new code to it. But it's been annoying me more and more, so now that I've decided C99 bool is an acceptable thing to require from our toolchain in the first place, here's a quite thorough trawl through the source doing 'boolification'. Many variables and function parameters are now typed as bool rather than int; many assignments of 0 or 1 to those variables are now spelled 'true' or 'false'. I managed this thorough conversion with the help of a custom clang plugin that I wrote to trawl the AST and apply heuristics to point out where things might want changing. So I've even managed to do a decent job on parts of the code I haven't looked at in years! To make the plugin's work easier, I pushed platform front ends generally in the direction of using standard 'bool' in preference to platform-specific boolean types like Windows BOOL or GTK's gboolean; I've left the platform booleans in places they _have_ to be for the platform APIs to work right, but variables only used by my own code have been converted wherever I found them. In a few places there are int values that look very like booleans in _most_ of the places they're used, but have a rarely-used third value, or a distinction between different nonzero values that most users don't care about. In these cases, I've _removed_ uses of 'true' and 'false' for the return values, to emphasise that there's something more subtle going on than a simple boolean answer: - the 'multisel' field in dialog.h's list box structure, for which the GTK front end in particular recognises a difference between 1 and 2 but nearly everything else treats as boolean - the 'urgent' parameter to plug_receive, where 1 vs 2 tells you something about the specific location of the urgent pointer, but most clients only care about 0 vs 'something nonzero' - the return value of wc_match, where -1 indicates a syntax error in the wildcard. - the return values from SSH-1 RSA-key loading functions, which use -1 for 'wrong passphrase' and 0 for all other failures (so any caller which already knows it's not loading an _encrypted private_ key can treat them as boolean) - term->esc_query, and the 'query' parameter in toggle_mode in terminal.c, which _usually_ hold 0 for ESC[123h or 1 for ESC[?123h, but can also hold -1 for some other intervening character that we don't support. In a few places there's an integer that I haven't turned into a bool even though it really _can_ only take values 0 or 1 (and, as above, tried to make the call sites consistent in not calling those values true and false), on the grounds that I thought it would make it more confusing to imply that the 0 value was in some sense 'negative' or bad and the 1 positive or good: - the return value of plug_accepting uses the POSIXish convention of 0=success and nonzero=error; I think if I made it bool then I'd also want to reverse its sense, and that's a job for a separate piece of work. - the 'screen' parameter to lineptr() in terminal.c, where 0 and 1 represent the default and alternate screens. There's no obvious reason why one of those should be considered 'true' or 'positive' or 'success' - they're just indices - so I've left it as int. ssh_scp_recv had particularly confusing semantics for its previous int return value: its call sites used '<= 0' to check for error, but it never actually returned a negative number, just 0 or 1. Now the function and its call sites agree that it's a bool. In a couple of places I've renamed variables called 'ret', because I don't like that name any more - it's unclear whether it means the return value (in preparation) for the _containing_ function or the return value received from a subroutine call, and occasionally I've accidentally used the same variable for both and introduced a bug. So where one of those got in my way, I've renamed it to 'toret' or 'retd' (the latter short for 'returned') in line with my usual modern practice, but I haven't done a thorough job of finding all of them. Finally, one amusing side effect of doing this is that I've had to separate quite a few chained assignments. It used to be perfectly fine to write 'a = b = c = TRUE' when a,b,c were int and TRUE was just a the 'true' defined by stdbool.h, that idiom provokes a warning from gcc: 'suggest parentheses around assignment used as truth value'!
2018-11-02 19:23:19 +00:00
bool ssh1_check_termination(struct ssh1_connection_state *s)
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
{
/*
* Decide whether we should terminate the SSH connection now.
* Called after a channel goes away, or when the main session
* returns SSH1_SMSG_EXIT_STATUS; we terminate when none of either
* is left.
*/
if (s->session_terminated && count234(s->channels) == 0) {
PktOut *pktout = ssh_bpp_new_pktout(
s->ppl.bpp, SSH1_CMSG_EXIT_CONFIRMATION);
pq_push(s->ppl.out_pq, pktout);
ssh_user_close(s->ppl.ssh, "Session finished");
Adopt C99 <stdbool.h>'s true/false. This commit includes <stdbool.h> from defs.h and deletes my traditional definitions of TRUE and FALSE, but other than that, it's a 100% mechanical search-and-replace transforming all uses of TRUE and FALSE into the C99-standardised lowercase spellings. No actual types are changed in this commit; that will come next. This is just getting the noise out of the way, so that subsequent commits can have a higher proportion of signal.
2018-10-29 19:50:29 +00:00
return true;
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
}
Adopt C99 <stdbool.h>'s true/false. This commit includes <stdbool.h> from defs.h and deletes my traditional definitions of TRUE and FALSE, but other than that, it's a 100% mechanical search-and-replace transforming all uses of TRUE and FALSE into the C99-standardised lowercase spellings. No actual types are changed in this commit; that will come next. This is just getting the noise out of the way, so that subsequent commits can have a higher proportion of signal.
2018-10-29 19:50:29 +00:00
return false;
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
}
/*
* Set up most of a new ssh1_channel. Leaves chan untouched (since it
* will sometimes have been filled in before calling this).
*/
Move client-specific SSH code into new files. This is a major code reorganisation in preparation for making this code base into one that can build an SSH server as well as a client. (Mostly for purposes of using the server as a regression test suite for the client, though I have some other possible uses in mind too. However, it's currently no part of my plan to harden the server to the point where it can sensibly be deployed in a hostile environment.) In this preparatory commit, I've broken up the SSH-2 transport and connection layers, and the SSH-1 connection layer, into multiple source files, with each layer having its own header file containing the shared type definitions. In each case, the new source file contains code that's specific to the client side of the protocol, so that a new file can be swapped in in its place when building the server. Mostly this is just a straightforward moving of code without changing it very much, but there are a couple of actual changes in the process: The parsing of SSH-2 global-request and channel open-messages is now done by a new pair of functions in the client module. For channel opens, I've invented a new union data type to be the return value from that function, representing either failure (plus error message), success (plus Channel instance to manage the new channel), or an instruction to hand the channel over to a sharing downstream (plus a pointer to the downstream in question). Also, the tree234 of remote port forwardings in ssh2connection is now initialised on first use by the client-specific code, so that's where its compare function lives. The shared ssh2connection_free() still takes responsibility for freeing it, but now has to check if it's non-null first. The outer shell of the ssh2_lportfwd_open method, for making a local-to-remote port forwarding, is still centralised in ssh2connection.c, but the part of it that actually constructs the outgoing channel-open message has moved into the client code, because that will have to change depending on whether the channel-open has to have type direct-tcpip or forwarded-tcpip. In the SSH-1 connection layer, half the filter_queue method has moved out into the new client-specific code, but not all of it - bidirectional channel maintenance messages are still handled centrally. One exception is SSH_MSG_PORT_OPEN, which can be sent in both directions, but with subtly different semantics - from server to client, it's referring to a previously established remote forwarding (and must be rejected if there isn't one that matches it), but from client to server it's just a "direct-tcpip" request with no prior context. So that one is in the client-specific module, and when I add the server code it will have its own different handler.
2018-10-20 16:57:37 +00:00
void ssh1_channel_init(struct ssh1_channel *c)
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
{
struct ssh1_connection_state *s = c->connlayer;
c->closes = 0;
Adopt C99 <stdbool.h>'s true/false. This commit includes <stdbool.h> from defs.h and deletes my traditional definitions of TRUE and FALSE, but other than that, it's a 100% mechanical search-and-replace transforming all uses of TRUE and FALSE into the C99-standardised lowercase spellings. No actual types are changed in this commit; that will come next. This is just getting the noise out of the way, so that subsequent commits can have a higher proportion of signal.
2018-10-29 19:50:29 +00:00
c->pending_eof = false;
c->throttling_conn = false;
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
c->sc.vt = &ssh1channel_vtable;
Give SshChannel a pointer to its owning ConnectionLayer. In my future plans, some SshChannels are going to need to be able to ask favours from the connection layer as a whole. And an SshChannel is inextricably tied to an instance of the connection layer, so there's no real reason _not_ to make the pointer generally available.
2018-10-14 16:17:48 +00:00
c->sc.cl = &s->cl;
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
c->localid = alloc_channel_id(s->channels, struct ssh1_channel);
add234(s->channels, c);
}
static Conf *ssh1channel_get_conf(SshChannel *sc)
{
Rename FROMFIELD to 'container_of'. Ian Jackson points out that the Linux kernel has a macro of this name with the same purpose, and suggests that it's a good idea to use the same name as they do, so that at least some people reading one code base might recognise it from the other. I never really thought very hard about what order FROMFIELD's parameters should go in, and therefore I'm pleasantly surprised to find that my order agrees with the kernel's, so I don't have to permute every call site as part of making this change :-)
2018-10-05 22:49:08 +00:00
struct ssh1_channel *c = container_of(sc, struct ssh1_channel, sc);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
struct ssh1_connection_state *s = c->connlayer;
return s->conf;
}
static void ssh1channel_write_eof(SshChannel *sc)
{
Rename FROMFIELD to 'container_of'. Ian Jackson points out that the Linux kernel has a macro of this name with the same purpose, and suggests that it's a good idea to use the same name as they do, so that at least some people reading one code base might recognise it from the other. I never really thought very hard about what order FROMFIELD's parameters should go in, and therefore I'm pleasantly surprised to find that my order agrees with the kernel's, so I don't have to permute every call site as part of making this change :-)
2018-10-05 22:49:08 +00:00
struct ssh1_channel *c = container_of(sc, struct ssh1_channel, sc);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
if (c->closes & CLOSES_SENT_CLOSE)
return;
Adopt C99 <stdbool.h>'s true/false. This commit includes <stdbool.h> from defs.h and deletes my traditional definitions of TRUE and FALSE, but other than that, it's a 100% mechanical search-and-replace transforming all uses of TRUE and FALSE into the C99-standardised lowercase spellings. No actual types are changed in this commit; that will come next. This is just getting the noise out of the way, so that subsequent commits can have a higher proportion of signal.
2018-10-29 19:50:29 +00:00
c->pending_eof = true;
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
ssh1_channel_try_eof(c);
}
Rename sshfwd_unclean_close to sshfwd_initiate_close. Turns out that initiation of a CHANNEL_CLOSE message before both sides have sent EOF is not only for _unclean_ closures or emergencies; it's actually a perfectly normal thing that some channel types want to do. (For example, a channel with a pty at the server end of it has no real concept of sending EOF independently in both directions: when the pty master sends EIO, the pty is no longer functioning, and you can no longer send to it any more than you can receive.)
2018-10-13 09:30:03 +00:00
static void ssh1channel_initiate_close(SshChannel *sc, const char *err)
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
{
Rename FROMFIELD to 'container_of'. Ian Jackson points out that the Linux kernel has a macro of this name with the same purpose, and suggests that it's a good idea to use the same name as they do, so that at least some people reading one code base might recognise it from the other. I never really thought very hard about what order FROMFIELD's parameters should go in, and therefore I'm pleasantly surprised to find that my order agrees with the kernel's, so I don't have to permute every call site as part of making this change :-)
2018-10-05 22:49:08 +00:00
struct ssh1_channel *c = container_of(sc, struct ssh1_channel, sc);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
char *reason;
Rename sshfwd_unclean_close to sshfwd_initiate_close. Turns out that initiation of a CHANNEL_CLOSE message before both sides have sent EOF is not only for _unclean_ closures or emergencies; it's actually a perfectly normal thing that some channel types want to do. (For example, a channel with a pty at the server end of it has no real concept of sending EOF independently in both directions: when the pty master sends EIO, the pty is no longer functioning, and you can no longer send to it any more than you can receive.)
2018-10-13 09:30:03 +00:00
reason = err ? dupprintf("due to local error: %s", err) : NULL;
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
ssh1_channel_close_local(c, reason);
sfree(reason);
Adopt C99 <stdbool.h>'s true/false. This commit includes <stdbool.h> from defs.h and deletes my traditional definitions of TRUE and FALSE, but other than that, it's a 100% mechanical search-and-replace transforming all uses of TRUE and FALSE into the C99-standardised lowercase spellings. No actual types are changed in this commit; that will come next. This is just getting the noise out of the way, so that subsequent commits can have a higher proportion of signal.
2018-10-29 19:50:29 +00:00
c->pending_eof = false; /* this will confuse a zombie channel */
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
ssh1_channel_check_close(c);
}
Make lots of 'int' length fields into size_t. This is a general cleanup which has been overdue for some time: lots of length fields are now the machine word type rather than the (in practice) fixed 'int'.
2019-02-06 20:42:44 +00:00
static void ssh1channel_unthrottle(SshChannel *sc, size_t bufsize)
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
{
Rename FROMFIELD to 'container_of'. Ian Jackson points out that the Linux kernel has a macro of this name with the same purpose, and suggests that it's a good idea to use the same name as they do, so that at least some people reading one code base might recognise it from the other. I never really thought very hard about what order FROMFIELD's parameters should go in, and therefore I'm pleasantly surprised to find that my order agrees with the kernel's, so I don't have to permute every call site as part of making this change :-)
2018-10-05 22:49:08 +00:00
struct ssh1_channel *c = container_of(sc, struct ssh1_channel, sc);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
struct ssh1_connection_state *s = c->connlayer;
if (c->throttling_conn && bufsize <= SSH1_BUFFER_LIMIT) {
Whitespace rationalisation of entire code base. The number of people has been steadily increasing who read our source code with an editor that thinks tab stops are 4 spaces apart, as opposed to the traditional tty-derived 8 that the PuTTY code expects. So I've been wondering for ages about just fixing it, and switching to a spaces-only policy throughout the code. And I recently found out about 'git blame -w', which should make this change not too disruptive for the purposes of source-control archaeology; so perhaps now is the time. While I'm at it, I've also taken the opportunity to remove all the trailing spaces from source lines (on the basis that git dislikes them, and is the only thing that seems to have a strong opinion one way or the other). Apologies to anyone downstream of this code who has complicated patch sets to rebase past this change. I don't intend it to be needed again.
2019-09-08 19:29:00 +00:00
c->throttling_conn = false;
ssh_throttle_conn(s->ppl.ssh, -1);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
}
}
Make lots of 'int' length fields into size_t. This is a general cleanup which has been overdue for some time: lots of length fields are now the machine word type rather than the (in practice) fixed 'int'.
2019-02-06 20:42:44 +00:00
static size_t ssh1channel_write(
SshChannel *sc, bool is_stderr, const void *buf, size_t len)
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
{
Rename FROMFIELD to 'container_of'. Ian Jackson points out that the Linux kernel has a macro of this name with the same purpose, and suggests that it's a good idea to use the same name as they do, so that at least some people reading one code base might recognise it from the other. I never really thought very hard about what order FROMFIELD's parameters should go in, and therefore I'm pleasantly surprised to find that my order agrees with the kernel's, so I don't have to permute every call site as part of making this change :-)
2018-10-05 22:49:08 +00:00
struct ssh1_channel *c = container_of(sc, struct ssh1_channel, sc);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
struct ssh1_connection_state *s = c->connlayer;
assert(!(c->closes & CLOSES_SENT_CLOSE));
PktOut *pktout = ssh_bpp_new_pktout(s->ppl.bpp, SSH1_MSG_CHANNEL_DATA);
put_uint32(pktout, c->remoteid);
put_string(pktout, buf, len);
pq_push(s->ppl.out_pq, pktout);
/*
* In SSH-1 we can return 0 here - implying that channels are
* never individually throttled - because the only circumstance
* that can cause throttling will be the whole SSH connection
* backing up, in which case _everything_ will be throttled as a
* whole.
*/
return 0;
}
Rewrite the SSH-1 main shell session using mainchan. In SSH-1, the channel system isn't rich enough to represent the complicated main shell session, so it's all done with a separate set of custom message types. But PuTTY now abstracts away that difference, by representing both as different implementations of the SshChannel class: ssh1channel is for things that the protocol thinks are 'really' channels, and ssh1mainchan is for the shell session. All the same methods are implemented, but generate different wire messages. This means that the logic to decide _when_ to enable X forwarding, agent forwarding etc is all centralised into mainchan.c, where it doesn't have to be repeated for both protocol versions. It also simplifies the final loop in the connection protocol, which no longer has to contain the code to move data from the user input bufchain to the channel's output; that's now done by the mainchan write method, the same as it is in SSH-2 where mainchan is just like other channels.
2018-09-30 10:22:01 +00:00
static struct X11FakeAuth *ssh1_add_x11_display(
ConnectionLayer *cl, int authtype, struct X11Display *disp)
{
struct ssh1_connection_state *s =
container_of(cl, struct ssh1_connection_state, cl);
struct X11FakeAuth *auth = x11_invent_fake_auth(s->x11authtree, authtype);
auth->disp = disp;
return auth;
}
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
static SshChannel *ssh1_lportfwd_open(
ConnectionLayer *cl, const char *hostname, int port,
Rename SocketPeerInfo to SocketEndpointInfo. I'm preparing to be able to ask about the other end of the connection too, so the first step is to give this data structure a neutral name that can refer to either. No functional change yet.
2024-06-26 05:35:40 +00:00
const char *description, const SocketEndpointInfo *pi, Channel *chan)
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
{
struct ssh1_connection_state *s =
Rename FROMFIELD to 'container_of'. Ian Jackson points out that the Linux kernel has a macro of this name with the same purpose, and suggests that it's a good idea to use the same name as they do, so that at least some people reading one code base might recognise it from the other. I never really thought very hard about what order FROMFIELD's parameters should go in, and therefore I'm pleasantly surprised to find that my order agrees with the kernel's, so I don't have to permute every call site as part of making this change :-)
2018-10-05 22:49:08 +00:00
container_of(cl, struct ssh1_connection_state, cl);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
PacketProtocolLayer *ppl = &s->ppl; /* for ppl_logevent */
struct ssh1_channel *c = snew(struct ssh1_channel);
PktOut *pktout;
c->connlayer = s;
ssh1_channel_init(c);
Adopt C99 <stdbool.h>'s true/false. This commit includes <stdbool.h> from defs.h and deletes my traditional definitions of TRUE and FALSE, but other than that, it's a 100% mechanical search-and-replace transforming all uses of TRUE and FALSE into the C99-standardised lowercase spellings. No actual types are changed in this commit; that will come next. This is just getting the noise out of the way, so that subsequent commits can have a higher proportion of signal.
2018-10-29 19:50:29 +00:00
c->halfopen = true;
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
c->chan = chan;
Start using C99 variadic macros. In the past, I've had a lot of macros which you call with double parentheses, along the lines of debug(("format string", params)), so that the inner parens protect the commas and permit the macro to treat the whole printf-style argument list as one macro argument. That's all very well, but it's a bit inconvenient (it doesn't leave you any way to implement such a macro by prepending another argument to the list), and now this code base's rules allow C99isms, I can switch all those macros to using a single pair of parens, using the C99 ability to say '...' in the parameter list of the #define and get at the corresponding suffix of the arguments as __VA_ARGS__. So I'm doing it. I've made the following printf-style macros variadic: bpp_logevent, ppl_logevent, ppl_printf and debug. While I'm here, I've also fixed up a collection of conditioned-out calls to debug() in the Windows front end which were clearly expecting a macro with a different calling syntax, because they had an integer parameter first. If I ever have a need to condition those back in, they should actually work now.
2018-12-08 20:32:31 +00:00
ppl_logevent("Opening connection to %s:%d for %s",
hostname, port, description);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
pktout = ssh_bpp_new_pktout(s->ppl.bpp, SSH1_MSG_PORT_OPEN);
put_uint32(pktout, c->localid);
put_stringz(pktout, hostname);
put_uint32(pktout, port);
/* originator string would go here, but we didn't specify
* SSH_PROTOFLAG_HOST_IN_FWD_OPEN */
pq_push(s->ppl.out_pq, pktout);
return &c->sc;
}
static void ssh1_rportfwd_remove(ConnectionLayer *cl, struct ssh_rportfwd *rpf)
{
/*
* We cannot cancel listening ports on the server side in SSH-1!
* There's no message to support it.
*/
}
Convert a lot of 'int' variables to 'bool'. My normal habit these days, in new code, is to treat int and bool as _almost_ completely separate types. I'm still willing to use C's implicit test for zero on an integer (e.g. 'if (!blob.len)' is fine, no need to spell it out as blob.len != 0), but generally, if a variable is going to be conceptually a boolean, I like to declare it bool and assign to it using 'true' or 'false' rather than 0 or 1. PuTTY is an exception, because it predates the C99 bool, and I've stuck to its existing coding style even when adding new code to it. But it's been annoying me more and more, so now that I've decided C99 bool is an acceptable thing to require from our toolchain in the first place, here's a quite thorough trawl through the source doing 'boolification'. Many variables and function parameters are now typed as bool rather than int; many assignments of 0 or 1 to those variables are now spelled 'true' or 'false'. I managed this thorough conversion with the help of a custom clang plugin that I wrote to trawl the AST and apply heuristics to point out where things might want changing. So I've even managed to do a decent job on parts of the code I haven't looked at in years! To make the plugin's work easier, I pushed platform front ends generally in the direction of using standard 'bool' in preference to platform-specific boolean types like Windows BOOL or GTK's gboolean; I've left the platform booleans in places they _have_ to be for the platform APIs to work right, but variables only used by my own code have been converted wherever I found them. In a few places there are int values that look very like booleans in _most_ of the places they're used, but have a rarely-used third value, or a distinction between different nonzero values that most users don't care about. In these cases, I've _removed_ uses of 'true' and 'false' for the return values, to emphasise that there's something more subtle going on than a simple boolean answer: - the 'multisel' field in dialog.h's list box structure, for which the GTK front end in particular recognises a difference between 1 and 2 but nearly everything else treats as boolean - the 'urgent' parameter to plug_receive, where 1 vs 2 tells you something about the specific location of the urgent pointer, but most clients only care about 0 vs 'something nonzero' - the return value of wc_match, where -1 indicates a syntax error in the wildcard. - the return values from SSH-1 RSA-key loading functions, which use -1 for 'wrong passphrase' and 0 for all other failures (so any caller which already knows it's not loading an _encrypted private_ key can treat them as boolean) - term->esc_query, and the 'query' parameter in toggle_mode in terminal.c, which _usually_ hold 0 for ESC[123h or 1 for ESC[?123h, but can also hold -1 for some other intervening character that we don't support. In a few places there's an integer that I haven't turned into a bool even though it really _can_ only take values 0 or 1 (and, as above, tried to make the call sites consistent in not calling those values true and false), on the grounds that I thought it would make it more confusing to imply that the 0 value was in some sense 'negative' or bad and the 1 positive or good: - the return value of plug_accepting uses the POSIXish convention of 0=success and nonzero=error; I think if I made it bool then I'd also want to reverse its sense, and that's a job for a separate piece of work. - the 'screen' parameter to lineptr() in terminal.c, where 0 and 1 represent the default and alternate screens. There's no obvious reason why one of those should be considered 'true' or 'positive' or 'success' - they're just indices - so I've left it as int. ssh_scp_recv had particularly confusing semantics for its previous int return value: its call sites used '<= 0' to check for error, but it never actually returned a negative number, just 0 or 1. Now the function and its call sites agree that it's a bool. In a couple of places I've renamed variables called 'ret', because I don't like that name any more - it's unclear whether it means the return value (in preparation) for the _containing_ function or the return value received from a subroutine call, and occasionally I've accidentally used the same variable for both and introduced a bug. So where one of those got in my way, I've renamed it to 'toret' or 'retd' (the latter short for 'returned') in line with my usual modern practice, but I haven't done a thorough job of finding all of them. Finally, one amusing side effect of doing this is that I've had to separate quite a few chained assignments. It used to be perfectly fine to write 'a = b = c = TRUE' when a,b,c were int and TRUE was just a the 'true' defined by stdbool.h, that idiom provokes a warning from gcc: 'suggest parentheses around assignment used as truth value'!
2018-11-02 19:23:19 +00:00
static bool ssh1_agent_forwarding_permitted(ConnectionLayer *cl)
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
{
struct ssh1_connection_state *s =
Rename FROMFIELD to 'container_of'. Ian Jackson points out that the Linux kernel has a macro of this name with the same purpose, and suggests that it's a good idea to use the same name as they do, so that at least some people reading one code base might recognise it from the other. I never really thought very hard about what order FROMFIELD's parameters should go in, and therefore I'm pleasantly surprised to find that my order agrees with the kernel's, so I don't have to permute every call site as part of making this change :-)
2018-10-05 22:49:08 +00:00
container_of(cl, struct ssh1_connection_state, cl);
Switch some Conf settings over to being bool. I think this is the full set of things that ought logically to be boolean. One annoyance is that quite a few radio-button controls in config.c address Conf fields that are now bool rather than int, which means that the shared handler function can't just access them all with conf_{get,set}_int. Rather than back out the rigorous separation of int and bool in conf.c itself, I've just added a similar alternative handler function for the bool-typed ones.
2018-10-29 19:57:31 +00:00
return conf_get_bool(s->conf, CONF_agentfwd) && agent_exists();
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
}
static void ssh1_connection_special_cmd(PacketProtocolLayer *ppl,
SessionSpecialCode code, int arg)
{
struct ssh1_connection_state *s =
Rename FROMFIELD to 'container_of'. Ian Jackson points out that the Linux kernel has a macro of this name with the same purpose, and suggests that it's a good idea to use the same name as they do, so that at least some people reading one code base might recognise it from the other. I never really thought very hard about what order FROMFIELD's parameters should go in, and therefore I'm pleasantly surprised to find that my order agrees with the kernel's, so I don't have to permute every call site as part of making this change :-)
2018-10-05 22:49:08 +00:00
container_of(ppl, struct ssh1_connection_state, ppl);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
PktOut *pktout;
if (code == SS_PING || code == SS_NOP) {
if (!(s->ppl.remote_bugs & BUG_CHOKES_ON_SSH1_IGNORE)) {
pktout = ssh_bpp_new_pktout(s->ppl.bpp, SSH1_MSG_IGNORE);
put_stringz(pktout, "");
pq_push(s->ppl.out_pq, pktout);
}
Rewrite the SSH-1 main shell session using mainchan. In SSH-1, the channel system isn't rich enough to represent the complicated main shell session, so it's all done with a separate set of custom message types. But PuTTY now abstracts away that difference, by representing both as different implementations of the SshChannel class: ssh1channel is for things that the protocol thinks are 'really' channels, and ssh1mainchan is for the shell session. All the same methods are implemented, but generate different wire messages. This means that the logic to decide _when_ to enable X forwarding, agent forwarding etc is all centralised into mainchan.c, where it doesn't have to be repeated for both protocol versions. It also simplifies the final loop in the connection protocol, which no longer has to contain the code to move data from the user input bufchain to the channel's output; that's now done by the mainchan write method, the same as it is in SSH-2 where mainchan is just like other channels.
2018-09-30 10:22:01 +00:00
} else if (s->mainchan) {
mainchan_special_cmd(s->mainchan, code, arg);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
}
}
static void ssh1_terminal_size(ConnectionLayer *cl, int width, int height)
{
struct ssh1_connection_state *s =
Rename FROMFIELD to 'container_of'. Ian Jackson points out that the Linux kernel has a macro of this name with the same purpose, and suggests that it's a good idea to use the same name as they do, so that at least some people reading one code base might recognise it from the other. I never really thought very hard about what order FROMFIELD's parameters should go in, and therefore I'm pleasantly surprised to find that my order agrees with the kernel's, so I don't have to permute every call site as part of making this change :-)
2018-10-05 22:49:08 +00:00
container_of(cl, struct ssh1_connection_state, cl);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
s->term_width = width;
s->term_height = height;
Rewrite the SSH-1 main shell session using mainchan. In SSH-1, the channel system isn't rich enough to represent the complicated main shell session, so it's all done with a separate set of custom message types. But PuTTY now abstracts away that difference, by representing both as different implementations of the SshChannel class: ssh1channel is for things that the protocol thinks are 'really' channels, and ssh1mainchan is for the shell session. All the same methods are implemented, but generate different wire messages. This means that the logic to decide _when_ to enable X forwarding, agent forwarding etc is all centralised into mainchan.c, where it doesn't have to be repeated for both protocol versions. It also simplifies the final loop in the connection protocol, which no longer has to contain the code to move data from the user input bufchain to the channel's output; that's now done by the mainchan write method, the same as it is in SSH-2 where mainchan is just like other channels.
2018-09-30 10:22:01 +00:00
if (s->mainchan)
mainchan_terminal_size(s->mainchan, width, height);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
}
Make lots of 'int' length fields into size_t. This is a general cleanup which has been overdue for some time: lots of length fields are now the machine word type rather than the (in practice) fixed 'int'.
2019-02-06 20:42:44 +00:00
static void ssh1_stdout_unthrottle(ConnectionLayer *cl, size_t bufsize)
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
{
struct ssh1_connection_state *s =
Rename FROMFIELD to 'container_of'. Ian Jackson points out that the Linux kernel has a macro of this name with the same purpose, and suggests that it's a good idea to use the same name as they do, so that at least some people reading one code base might recognise it from the other. I never really thought very hard about what order FROMFIELD's parameters should go in, and therefore I'm pleasantly surprised to find that my order agrees with the kernel's, so I don't have to permute every call site as part of making this change :-)
2018-10-05 22:49:08 +00:00
container_of(cl, struct ssh1_connection_state, cl);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
if (s->stdout_throttling && bufsize < SSH1_BUFFER_LIMIT) {
Convert a lot of 'int' variables to 'bool'. My normal habit these days, in new code, is to treat int and bool as _almost_ completely separate types. I'm still willing to use C's implicit test for zero on an integer (e.g. 'if (!blob.len)' is fine, no need to spell it out as blob.len != 0), but generally, if a variable is going to be conceptually a boolean, I like to declare it bool and assign to it using 'true' or 'false' rather than 0 or 1. PuTTY is an exception, because it predates the C99 bool, and I've stuck to its existing coding style even when adding new code to it. But it's been annoying me more and more, so now that I've decided C99 bool is an acceptable thing to require from our toolchain in the first place, here's a quite thorough trawl through the source doing 'boolification'. Many variables and function parameters are now typed as bool rather than int; many assignments of 0 or 1 to those variables are now spelled 'true' or 'false'. I managed this thorough conversion with the help of a custom clang plugin that I wrote to trawl the AST and apply heuristics to point out where things might want changing. So I've even managed to do a decent job on parts of the code I haven't looked at in years! To make the plugin's work easier, I pushed platform front ends generally in the direction of using standard 'bool' in preference to platform-specific boolean types like Windows BOOL or GTK's gboolean; I've left the platform booleans in places they _have_ to be for the platform APIs to work right, but variables only used by my own code have been converted wherever I found them. In a few places there are int values that look very like booleans in _most_ of the places they're used, but have a rarely-used third value, or a distinction between different nonzero values that most users don't care about. In these cases, I've _removed_ uses of 'true' and 'false' for the return values, to emphasise that there's something more subtle going on than a simple boolean answer: - the 'multisel' field in dialog.h's list box structure, for which the GTK front end in particular recognises a difference between 1 and 2 but nearly everything else treats as boolean - the 'urgent' parameter to plug_receive, where 1 vs 2 tells you something about the specific location of the urgent pointer, but most clients only care about 0 vs 'something nonzero' - the return value of wc_match, where -1 indicates a syntax error in the wildcard. - the return values from SSH-1 RSA-key loading functions, which use -1 for 'wrong passphrase' and 0 for all other failures (so any caller which already knows it's not loading an _encrypted private_ key can treat them as boolean) - term->esc_query, and the 'query' parameter in toggle_mode in terminal.c, which _usually_ hold 0 for ESC[123h or 1 for ESC[?123h, but can also hold -1 for some other intervening character that we don't support. In a few places there's an integer that I haven't turned into a bool even though it really _can_ only take values 0 or 1 (and, as above, tried to make the call sites consistent in not calling those values true and false), on the grounds that I thought it would make it more confusing to imply that the 0 value was in some sense 'negative' or bad and the 1 positive or good: - the return value of plug_accepting uses the POSIXish convention of 0=success and nonzero=error; I think if I made it bool then I'd also want to reverse its sense, and that's a job for a separate piece of work. - the 'screen' parameter to lineptr() in terminal.c, where 0 and 1 represent the default and alternate screens. There's no obvious reason why one of those should be considered 'true' or 'positive' or 'success' - they're just indices - so I've left it as int. ssh_scp_recv had particularly confusing semantics for its previous int return value: its call sites used '<= 0' to check for error, but it never actually returned a negative number, just 0 or 1. Now the function and its call sites agree that it's a bool. In a couple of places I've renamed variables called 'ret', because I don't like that name any more - it's unclear whether it means the return value (in preparation) for the _containing_ function or the return value received from a subroutine call, and occasionally I've accidentally used the same variable for both and introduced a bug. So where one of those got in my way, I've renamed it to 'toret' or 'retd' (the latter short for 'returned') in line with my usual modern practice, but I haven't done a thorough job of finding all of them. Finally, one amusing side effect of doing this is that I've had to separate quite a few chained assignments. It used to be perfectly fine to write 'a = b = c = TRUE' when a,b,c were int and TRUE was just a the 'true' defined by stdbool.h, that idiom provokes a warning from gcc: 'suggest parentheses around assignment used as truth value'!
2018-11-02 19:23:19 +00:00
s->stdout_throttling = false;
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
ssh_throttle_conn(s->ppl.ssh, -1);
}
}
Make lots of 'int' length fields into size_t. This is a general cleanup which has been overdue for some time: lots of length fields are now the machine word type rather than the (in practice) fixed 'int'.
2019-02-06 20:42:44 +00:00
static size_t ssh1_stdin_backlog(ConnectionLayer *cl)
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
{
return 0;
}
Convert a lot of 'int' variables to 'bool'. My normal habit these days, in new code, is to treat int and bool as _almost_ completely separate types. I'm still willing to use C's implicit test for zero on an integer (e.g. 'if (!blob.len)' is fine, no need to spell it out as blob.len != 0), but generally, if a variable is going to be conceptually a boolean, I like to declare it bool and assign to it using 'true' or 'false' rather than 0 or 1. PuTTY is an exception, because it predates the C99 bool, and I've stuck to its existing coding style even when adding new code to it. But it's been annoying me more and more, so now that I've decided C99 bool is an acceptable thing to require from our toolchain in the first place, here's a quite thorough trawl through the source doing 'boolification'. Many variables and function parameters are now typed as bool rather than int; many assignments of 0 or 1 to those variables are now spelled 'true' or 'false'. I managed this thorough conversion with the help of a custom clang plugin that I wrote to trawl the AST and apply heuristics to point out where things might want changing. So I've even managed to do a decent job on parts of the code I haven't looked at in years! To make the plugin's work easier, I pushed platform front ends generally in the direction of using standard 'bool' in preference to platform-specific boolean types like Windows BOOL or GTK's gboolean; I've left the platform booleans in places they _have_ to be for the platform APIs to work right, but variables only used by my own code have been converted wherever I found them. In a few places there are int values that look very like booleans in _most_ of the places they're used, but have a rarely-used third value, or a distinction between different nonzero values that most users don't care about. In these cases, I've _removed_ uses of 'true' and 'false' for the return values, to emphasise that there's something more subtle going on than a simple boolean answer: - the 'multisel' field in dialog.h's list box structure, for which the GTK front end in particular recognises a difference between 1 and 2 but nearly everything else treats as boolean - the 'urgent' parameter to plug_receive, where 1 vs 2 tells you something about the specific location of the urgent pointer, but most clients only care about 0 vs 'something nonzero' - the return value of wc_match, where -1 indicates a syntax error in the wildcard. - the return values from SSH-1 RSA-key loading functions, which use -1 for 'wrong passphrase' and 0 for all other failures (so any caller which already knows it's not loading an _encrypted private_ key can treat them as boolean) - term->esc_query, and the 'query' parameter in toggle_mode in terminal.c, which _usually_ hold 0 for ESC[123h or 1 for ESC[?123h, but can also hold -1 for some other intervening character that we don't support. In a few places there's an integer that I haven't turned into a bool even though it really _can_ only take values 0 or 1 (and, as above, tried to make the call sites consistent in not calling those values true and false), on the grounds that I thought it would make it more confusing to imply that the 0 value was in some sense 'negative' or bad and the 1 positive or good: - the return value of plug_accepting uses the POSIXish convention of 0=success and nonzero=error; I think if I made it bool then I'd also want to reverse its sense, and that's a job for a separate piece of work. - the 'screen' parameter to lineptr() in terminal.c, where 0 and 1 represent the default and alternate screens. There's no obvious reason why one of those should be considered 'true' or 'positive' or 'success' - they're just indices - so I've left it as int. ssh_scp_recv had particularly confusing semantics for its previous int return value: its call sites used '<= 0' to check for error, but it never actually returned a negative number, just 0 or 1. Now the function and its call sites agree that it's a bool. In a couple of places I've renamed variables called 'ret', because I don't like that name any more - it's unclear whether it means the return value (in preparation) for the _containing_ function or the return value received from a subroutine call, and occasionally I've accidentally used the same variable for both and introduced a bug. So where one of those got in my way, I've renamed it to 'toret' or 'retd' (the latter short for 'returned') in line with my usual modern practice, but I haven't done a thorough job of finding all of them. Finally, one amusing side effect of doing this is that I've had to separate quite a few chained assignments. It used to be perfectly fine to write 'a = b = c = TRUE' when a,b,c were int and TRUE was just a the 'true' defined by stdbool.h, that idiom provokes a warning from gcc: 'suggest parentheses around assignment used as truth value'!
2018-11-02 19:23:19 +00:00
static void ssh1_throttle_all_channels(ConnectionLayer *cl, bool throttled)
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
{
struct ssh1_connection_state *s =
Rename FROMFIELD to 'container_of'. Ian Jackson points out that the Linux kernel has a macro of this name with the same purpose, and suggests that it's a good idea to use the same name as they do, so that at least some people reading one code base might recognise it from the other. I never really thought very hard about what order FROMFIELD's parameters should go in, and therefore I'm pleasantly surprised to find that my order agrees with the kernel's, so I don't have to permute every call site as part of making this change :-)
2018-10-05 22:49:08 +00:00
container_of(cl, struct ssh1_connection_state, cl);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
struct ssh1_channel *c;
int i;
for (i = 0; NULL != (c = index234(s->channels, i)); i++)
chan_set_input_wanted(c->chan, !throttled);
}
Convert a lot of 'int' variables to 'bool'. My normal habit these days, in new code, is to treat int and bool as _almost_ completely separate types. I'm still willing to use C's implicit test for zero on an integer (e.g. 'if (!blob.len)' is fine, no need to spell it out as blob.len != 0), but generally, if a variable is going to be conceptually a boolean, I like to declare it bool and assign to it using 'true' or 'false' rather than 0 or 1. PuTTY is an exception, because it predates the C99 bool, and I've stuck to its existing coding style even when adding new code to it. But it's been annoying me more and more, so now that I've decided C99 bool is an acceptable thing to require from our toolchain in the first place, here's a quite thorough trawl through the source doing 'boolification'. Many variables and function parameters are now typed as bool rather than int; many assignments of 0 or 1 to those variables are now spelled 'true' or 'false'. I managed this thorough conversion with the help of a custom clang plugin that I wrote to trawl the AST and apply heuristics to point out where things might want changing. So I've even managed to do a decent job on parts of the code I haven't looked at in years! To make the plugin's work easier, I pushed platform front ends generally in the direction of using standard 'bool' in preference to platform-specific boolean types like Windows BOOL or GTK's gboolean; I've left the platform booleans in places they _have_ to be for the platform APIs to work right, but variables only used by my own code have been converted wherever I found them. In a few places there are int values that look very like booleans in _most_ of the places they're used, but have a rarely-used third value, or a distinction between different nonzero values that most users don't care about. In these cases, I've _removed_ uses of 'true' and 'false' for the return values, to emphasise that there's something more subtle going on than a simple boolean answer: - the 'multisel' field in dialog.h's list box structure, for which the GTK front end in particular recognises a difference between 1 and 2 but nearly everything else treats as boolean - the 'urgent' parameter to plug_receive, where 1 vs 2 tells you something about the specific location of the urgent pointer, but most clients only care about 0 vs 'something nonzero' - the return value of wc_match, where -1 indicates a syntax error in the wildcard. - the return values from SSH-1 RSA-key loading functions, which use -1 for 'wrong passphrase' and 0 for all other failures (so any caller which already knows it's not loading an _encrypted private_ key can treat them as boolean) - term->esc_query, and the 'query' parameter in toggle_mode in terminal.c, which _usually_ hold 0 for ESC[123h or 1 for ESC[?123h, but can also hold -1 for some other intervening character that we don't support. In a few places there's an integer that I haven't turned into a bool even though it really _can_ only take values 0 or 1 (and, as above, tried to make the call sites consistent in not calling those values true and false), on the grounds that I thought it would make it more confusing to imply that the 0 value was in some sense 'negative' or bad and the 1 positive or good: - the return value of plug_accepting uses the POSIXish convention of 0=success and nonzero=error; I think if I made it bool then I'd also want to reverse its sense, and that's a job for a separate piece of work. - the 'screen' parameter to lineptr() in terminal.c, where 0 and 1 represent the default and alternate screens. There's no obvious reason why one of those should be considered 'true' or 'positive' or 'success' - they're just indices - so I've left it as int. ssh_scp_recv had particularly confusing semantics for its previous int return value: its call sites used '<= 0' to check for error, but it never actually returned a negative number, just 0 or 1. Now the function and its call sites agree that it's a bool. In a couple of places I've renamed variables called 'ret', because I don't like that name any more - it's unclear whether it means the return value (in preparation) for the _containing_ function or the return value received from a subroutine call, and occasionally I've accidentally used the same variable for both and introduced a bug. So where one of those got in my way, I've renamed it to 'toret' or 'retd' (the latter short for 'returned') in line with my usual modern practice, but I haven't done a thorough job of finding all of them. Finally, one amusing side effect of doing this is that I've had to separate quite a few chained assignments. It used to be perfectly fine to write 'a = b = c = TRUE' when a,b,c were int and TRUE was just a the 'true' defined by stdbool.h, that idiom provokes a warning from gcc: 'suggest parentheses around assignment used as truth value'!
2018-11-02 19:23:19 +00:00
static bool ssh1_ldisc_option(ConnectionLayer *cl, int option)
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
{
struct ssh1_connection_state *s =
Rename FROMFIELD to 'container_of'. Ian Jackson points out that the Linux kernel has a macro of this name with the same purpose, and suggests that it's a good idea to use the same name as they do, so that at least some people reading one code base might recognise it from the other. I never really thought very hard about what order FROMFIELD's parameters should go in, and therefore I'm pleasantly surprised to find that my order agrees with the kernel's, so I don't have to permute every call site as part of making this change :-)
2018-10-05 22:49:08 +00:00
container_of(cl, struct ssh1_connection_state, cl);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
Rewrite the SSH-1 main shell session using mainchan. In SSH-1, the channel system isn't rich enough to represent the complicated main shell session, so it's all done with a separate set of custom message types. But PuTTY now abstracts away that difference, by representing both as different implementations of the SshChannel class: ssh1channel is for things that the protocol thinks are 'really' channels, and ssh1mainchan is for the shell session. All the same methods are implemented, but generate different wire messages. This means that the logic to decide _when_ to enable X forwarding, agent forwarding etc is all centralised into mainchan.c, where it doesn't have to be repeated for both protocol versions. It also simplifies the final loop in the connection protocol, which no longer has to contain the code to move data from the user input bufchain to the channel's output; that's now done by the mainchan write method, the same as it is in SSH-2 where mainchan is just like other channels.
2018-09-30 10:22:01 +00:00
return s->ldisc_opts[option];
}
Convert a lot of 'int' variables to 'bool'. My normal habit these days, in new code, is to treat int and bool as _almost_ completely separate types. I'm still willing to use C's implicit test for zero on an integer (e.g. 'if (!blob.len)' is fine, no need to spell it out as blob.len != 0), but generally, if a variable is going to be conceptually a boolean, I like to declare it bool and assign to it using 'true' or 'false' rather than 0 or 1. PuTTY is an exception, because it predates the C99 bool, and I've stuck to its existing coding style even when adding new code to it. But it's been annoying me more and more, so now that I've decided C99 bool is an acceptable thing to require from our toolchain in the first place, here's a quite thorough trawl through the source doing 'boolification'. Many variables and function parameters are now typed as bool rather than int; many assignments of 0 or 1 to those variables are now spelled 'true' or 'false'. I managed this thorough conversion with the help of a custom clang plugin that I wrote to trawl the AST and apply heuristics to point out where things might want changing. So I've even managed to do a decent job on parts of the code I haven't looked at in years! To make the plugin's work easier, I pushed platform front ends generally in the direction of using standard 'bool' in preference to platform-specific boolean types like Windows BOOL or GTK's gboolean; I've left the platform booleans in places they _have_ to be for the platform APIs to work right, but variables only used by my own code have been converted wherever I found them. In a few places there are int values that look very like booleans in _most_ of the places they're used, but have a rarely-used third value, or a distinction between different nonzero values that most users don't care about. In these cases, I've _removed_ uses of 'true' and 'false' for the return values, to emphasise that there's something more subtle going on than a simple boolean answer: - the 'multisel' field in dialog.h's list box structure, for which the GTK front end in particular recognises a difference between 1 and 2 but nearly everything else treats as boolean - the 'urgent' parameter to plug_receive, where 1 vs 2 tells you something about the specific location of the urgent pointer, but most clients only care about 0 vs 'something nonzero' - the return value of wc_match, where -1 indicates a syntax error in the wildcard. - the return values from SSH-1 RSA-key loading functions, which use -1 for 'wrong passphrase' and 0 for all other failures (so any caller which already knows it's not loading an _encrypted private_ key can treat them as boolean) - term->esc_query, and the 'query' parameter in toggle_mode in terminal.c, which _usually_ hold 0 for ESC[123h or 1 for ESC[?123h, but can also hold -1 for some other intervening character that we don't support. In a few places there's an integer that I haven't turned into a bool even though it really _can_ only take values 0 or 1 (and, as above, tried to make the call sites consistent in not calling those values true and false), on the grounds that I thought it would make it more confusing to imply that the 0 value was in some sense 'negative' or bad and the 1 positive or good: - the return value of plug_accepting uses the POSIXish convention of 0=success and nonzero=error; I think if I made it bool then I'd also want to reverse its sense, and that's a job for a separate piece of work. - the 'screen' parameter to lineptr() in terminal.c, where 0 and 1 represent the default and alternate screens. There's no obvious reason why one of those should be considered 'true' or 'positive' or 'success' - they're just indices - so I've left it as int. ssh_scp_recv had particularly confusing semantics for its previous int return value: its call sites used '<= 0' to check for error, but it never actually returned a negative number, just 0 or 1. Now the function and its call sites agree that it's a bool. In a couple of places I've renamed variables called 'ret', because I don't like that name any more - it's unclear whether it means the return value (in preparation) for the _containing_ function or the return value received from a subroutine call, and occasionally I've accidentally used the same variable for both and introduced a bug. So where one of those got in my way, I've renamed it to 'toret' or 'retd' (the latter short for 'returned') in line with my usual modern practice, but I haven't done a thorough job of finding all of them. Finally, one amusing side effect of doing this is that I've had to separate quite a few chained assignments. It used to be perfectly fine to write 'a = b = c = TRUE' when a,b,c were int and TRUE was just a the 'true' defined by stdbool.h, that idiom provokes a warning from gcc: 'suggest parentheses around assignment used as truth value'!
2018-11-02 19:23:19 +00:00
static void ssh1_set_ldisc_option(ConnectionLayer *cl, int option, bool value)
Rewrite the SSH-1 main shell session using mainchan. In SSH-1, the channel system isn't rich enough to represent the complicated main shell session, so it's all done with a separate set of custom message types. But PuTTY now abstracts away that difference, by representing both as different implementations of the SshChannel class: ssh1channel is for things that the protocol thinks are 'really' channels, and ssh1mainchan is for the shell session. All the same methods are implemented, but generate different wire messages. This means that the logic to decide _when_ to enable X forwarding, agent forwarding etc is all centralised into mainchan.c, where it doesn't have to be repeated for both protocol versions. It also simplifies the final loop in the connection protocol, which no longer has to contain the code to move data from the user input bufchain to the channel's output; that's now done by the mainchan write method, the same as it is in SSH-2 where mainchan is just like other channels.
2018-09-30 10:22:01 +00:00
{
struct ssh1_connection_state *s =
container_of(cl, struct ssh1_connection_state, cl);
s->ldisc_opts[option] = value;
}
static void ssh1_enable_x_fwd(ConnectionLayer *cl)
{
struct ssh1_connection_state *s =
container_of(cl, struct ssh1_connection_state, cl);
Adopt C99 <stdbool.h>'s true/false. This commit includes <stdbool.h> from defs.h and deletes my traditional definitions of TRUE and FALSE, but other than that, it's a 100% mechanical search-and-replace transforming all uses of TRUE and FALSE into the C99-standardised lowercase spellings. No actual types are changed in this commit; that will come next. This is just getting the noise out of the way, so that subsequent commits can have a higher proportion of signal.
2018-10-29 19:50:29 +00:00
s->X11_fwd_enabled = true;
Rewrite the SSH-1 main shell session using mainchan. In SSH-1, the channel system isn't rich enough to represent the complicated main shell session, so it's all done with a separate set of custom message types. But PuTTY now abstracts away that difference, by representing both as different implementations of the SshChannel class: ssh1channel is for things that the protocol thinks are 'really' channels, and ssh1mainchan is for the shell session. All the same methods are implemented, but generate different wire messages. This means that the logic to decide _when_ to enable X forwarding, agent forwarding etc is all centralised into mainchan.c, where it doesn't have to be repeated for both protocol versions. It also simplifies the final loop in the connection protocol, which no longer has to contain the code to move data from the user input bufchain to the channel's output; that's now done by the mainchan write method, the same as it is in SSH-2 where mainchan is just like other channels.
2018-09-30 10:22:01 +00:00
}
Convert a lot of 'int' variables to 'bool'. My normal habit these days, in new code, is to treat int and bool as _almost_ completely separate types. I'm still willing to use C's implicit test for zero on an integer (e.g. 'if (!blob.len)' is fine, no need to spell it out as blob.len != 0), but generally, if a variable is going to be conceptually a boolean, I like to declare it bool and assign to it using 'true' or 'false' rather than 0 or 1. PuTTY is an exception, because it predates the C99 bool, and I've stuck to its existing coding style even when adding new code to it. But it's been annoying me more and more, so now that I've decided C99 bool is an acceptable thing to require from our toolchain in the first place, here's a quite thorough trawl through the source doing 'boolification'. Many variables and function parameters are now typed as bool rather than int; many assignments of 0 or 1 to those variables are now spelled 'true' or 'false'. I managed this thorough conversion with the help of a custom clang plugin that I wrote to trawl the AST and apply heuristics to point out where things might want changing. So I've even managed to do a decent job on parts of the code I haven't looked at in years! To make the plugin's work easier, I pushed platform front ends generally in the direction of using standard 'bool' in preference to platform-specific boolean types like Windows BOOL or GTK's gboolean; I've left the platform booleans in places they _have_ to be for the platform APIs to work right, but variables only used by my own code have been converted wherever I found them. In a few places there are int values that look very like booleans in _most_ of the places they're used, but have a rarely-used third value, or a distinction between different nonzero values that most users don't care about. In these cases, I've _removed_ uses of 'true' and 'false' for the return values, to emphasise that there's something more subtle going on than a simple boolean answer: - the 'multisel' field in dialog.h's list box structure, for which the GTK front end in particular recognises a difference between 1 and 2 but nearly everything else treats as boolean - the 'urgent' parameter to plug_receive, where 1 vs 2 tells you something about the specific location of the urgent pointer, but most clients only care about 0 vs 'something nonzero' - the return value of wc_match, where -1 indicates a syntax error in the wildcard. - the return values from SSH-1 RSA-key loading functions, which use -1 for 'wrong passphrase' and 0 for all other failures (so any caller which already knows it's not loading an _encrypted private_ key can treat them as boolean) - term->esc_query, and the 'query' parameter in toggle_mode in terminal.c, which _usually_ hold 0 for ESC[123h or 1 for ESC[?123h, but can also hold -1 for some other intervening character that we don't support. In a few places there's an integer that I haven't turned into a bool even though it really _can_ only take values 0 or 1 (and, as above, tried to make the call sites consistent in not calling those values true and false), on the grounds that I thought it would make it more confusing to imply that the 0 value was in some sense 'negative' or bad and the 1 positive or good: - the return value of plug_accepting uses the POSIXish convention of 0=success and nonzero=error; I think if I made it bool then I'd also want to reverse its sense, and that's a job for a separate piece of work. - the 'screen' parameter to lineptr() in terminal.c, where 0 and 1 represent the default and alternate screens. There's no obvious reason why one of those should be considered 'true' or 'positive' or 'success' - they're just indices - so I've left it as int. ssh_scp_recv had particularly confusing semantics for its previous int return value: its call sites used '<= 0' to check for error, but it never actually returned a negative number, just 0 or 1. Now the function and its call sites agree that it's a bool. In a couple of places I've renamed variables called 'ret', because I don't like that name any more - it's unclear whether it means the return value (in preparation) for the _containing_ function or the return value received from a subroutine call, and occasionally I've accidentally used the same variable for both and introduced a bug. So where one of those got in my way, I've renamed it to 'toret' or 'retd' (the latter short for 'returned') in line with my usual modern practice, but I haven't done a thorough job of finding all of them. Finally, one amusing side effect of doing this is that I've had to separate quite a few chained assignments. It used to be perfectly fine to write 'a = b = c = TRUE' when a,b,c were int and TRUE was just a the 'true' defined by stdbool.h, that idiom provokes a warning from gcc: 'suggest parentheses around assignment used as truth value'!
2018-11-02 19:23:19 +00:00
static void ssh1_set_wants_user_input(ConnectionLayer *cl, bool wanted)
Rewrite the SSH-1 main shell session using mainchan. In SSH-1, the channel system isn't rich enough to represent the complicated main shell session, so it's all done with a separate set of custom message types. But PuTTY now abstracts away that difference, by representing both as different implementations of the SshChannel class: ssh1channel is for things that the protocol thinks are 'really' channels, and ssh1mainchan is for the shell session. All the same methods are implemented, but generate different wire messages. This means that the logic to decide _when_ to enable X forwarding, agent forwarding etc is all centralised into mainchan.c, where it doesn't have to be repeated for both protocol versions. It also simplifies the final loop in the connection protocol, which no longer has to contain the code to move data from the user input bufchain to the channel's output; that's now done by the mainchan write method, the same as it is in SSH-2 where mainchan is just like other channels.
2018-09-30 10:22:01 +00:00
{
struct ssh1_connection_state *s =
container_of(cl, struct ssh1_connection_state, cl);
s->want_user_input = wanted;
Adopt C99 <stdbool.h>'s true/false. This commit includes <stdbool.h> from defs.h and deletes my traditional definitions of TRUE and FALSE, but other than that, it's a 100% mechanical search-and-replace transforming all uses of TRUE and FALSE into the C99-standardised lowercase spellings. No actual types are changed in this commit; that will come next. This is just getting the noise out of the way, so that subsequent commits can have a higher proportion of signal.
2018-10-29 19:50:29 +00:00
s->finished_setup = true;
Backends: notify ldisc when sendok becomes true. (NFC) I've introduced a function ldisc_notify_sendok(), which backends should call on their ldisc (if they have one) when anything changes that might cause backend_sendok() to start returning true. At the moment, the function does nothing. But in future, I'm going to make ldisc start buffering typed-ahead input data not yet sent to the backend, and then the effect of this function will be to trigger flushing all that data into the backend. Backends only have to call this function if sendok was previously false: backends requiring no network connection stage (like pty and serial) can safely return true from sendok, and in that case, they don't also have to immediately call this function.
2021-09-14 09:13:28 +00:00
if (wanted)
ssh_check_sendok(s->ppl.ssh);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
}
Localise user_input to SSH connection layers. Now that the SSH backend's user_input bufchain is no longer needed for handling userpass input, it doesn't have to be awkwardly shared between all the packet protocol layers any more. So we can turn the want_user_input and got_user_input methods of PacketProtocolLayer into methods of ConnectionLayer, and then only the two connection layers have to bother implementing them, or store a pointer to the bufchain they read from.
2021-09-14 13:00:05 +00:00
static bool ssh1_get_wants_user_input(ConnectionLayer *cl)
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
{
struct ssh1_connection_state *s =
Localise user_input to SSH connection layers. Now that the SSH backend's user_input bufchain is no longer needed for handling userpass input, it doesn't have to be awkwardly shared between all the packet protocol layers any more. So we can turn the want_user_input and got_user_input methods of PacketProtocolLayer into methods of ConnectionLayer, and then only the two connection layers have to bother implementing them, or store a pointer to the bufchain they read from.
2021-09-14 13:00:05 +00:00
container_of(cl, struct ssh1_connection_state, cl);
Rewrite the SSH-1 main shell session using mainchan. In SSH-1, the channel system isn't rich enough to represent the complicated main shell session, so it's all done with a separate set of custom message types. But PuTTY now abstracts away that difference, by representing both as different implementations of the SshChannel class: ssh1channel is for things that the protocol thinks are 'really' channels, and ssh1mainchan is for the shell session. All the same methods are implemented, but generate different wire messages. This means that the logic to decide _when_ to enable X forwarding, agent forwarding etc is all centralised into mainchan.c, where it doesn't have to be repeated for both protocol versions. It also simplifies the final loop in the connection protocol, which no longer has to contain the code to move data from the user input bufchain to the channel's output; that's now done by the mainchan write method, the same as it is in SSH-2 where mainchan is just like other channels.
2018-09-30 10:22:01 +00:00
return s->want_user_input;
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
}
Localise user_input to SSH connection layers. Now that the SSH backend's user_input bufchain is no longer needed for handling userpass input, it doesn't have to be awkwardly shared between all the packet protocol layers any more. So we can turn the want_user_input and got_user_input methods of PacketProtocolLayer into methods of ConnectionLayer, and then only the two connection layers have to bother implementing them, or store a pointer to the bufchain they read from.
2021-09-14 13:00:05 +00:00
static void ssh1_got_user_input(ConnectionLayer *cl)
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
{
struct ssh1_connection_state *s =
Localise user_input to SSH connection layers. Now that the SSH backend's user_input bufchain is no longer needed for handling userpass input, it doesn't have to be awkwardly shared between all the packet protocol layers any more. So we can turn the want_user_input and got_user_input methods of PacketProtocolLayer into methods of ConnectionLayer, and then only the two connection layers have to bother implementing them, or store a pointer to the bufchain they read from.
2021-09-14 13:00:05 +00:00
container_of(cl, struct ssh1_connection_state, cl);
Rewrite the SSH-1 main shell session using mainchan. In SSH-1, the channel system isn't rich enough to represent the complicated main shell session, so it's all done with a separate set of custom message types. But PuTTY now abstracts away that difference, by representing both as different implementations of the SshChannel class: ssh1channel is for things that the protocol thinks are 'really' channels, and ssh1mainchan is for the shell session. All the same methods are implemented, but generate different wire messages. This means that the logic to decide _when_ to enable X forwarding, agent forwarding etc is all centralised into mainchan.c, where it doesn't have to be repeated for both protocol versions. It also simplifies the final loop in the connection protocol, which no longer has to contain the code to move data from the user input bufchain to the channel's output; that's now done by the mainchan write method, the same as it is in SSH-2 where mainchan is just like other channels.
2018-09-30 10:22:01 +00:00
Localise user_input to SSH connection layers. Now that the SSH backend's user_input bufchain is no longer needed for handling userpass input, it doesn't have to be awkwardly shared between all the packet protocol layers any more. So we can turn the want_user_input and got_user_input methods of PacketProtocolLayer into methods of ConnectionLayer, and then only the two connection layers have to bother implementing them, or store a pointer to the bufchain they read from.
2021-09-14 13:00:05 +00:00
while (s->mainchan && bufchain_size(s->user_input) > 0) {
Rewrite the SSH-1 main shell session using mainchan. In SSH-1, the channel system isn't rich enough to represent the complicated main shell session, so it's all done with a separate set of custom message types. But PuTTY now abstracts away that difference, by representing both as different implementations of the SshChannel class: ssh1channel is for things that the protocol thinks are 'really' channels, and ssh1mainchan is for the shell session. All the same methods are implemented, but generate different wire messages. This means that the logic to decide _when_ to enable X forwarding, agent forwarding etc is all centralised into mainchan.c, where it doesn't have to be repeated for both protocol versions. It also simplifies the final loop in the connection protocol, which no longer has to contain the code to move data from the user input bufchain to the channel's output; that's now done by the mainchan write method, the same as it is in SSH-2 where mainchan is just like other channels.
2018-09-30 10:22:01 +00:00
/*
* Add user input to the main channel's buffer.
*/
Localise user_input to SSH connection layers. Now that the SSH backend's user_input bufchain is no longer needed for handling userpass input, it doesn't have to be awkwardly shared between all the packet protocol layers any more. So we can turn the want_user_input and got_user_input methods of PacketProtocolLayer into methods of ConnectionLayer, and then only the two connection layers have to bother implementing them, or store a pointer to the bufchain they read from.
2021-09-14 13:00:05 +00:00
ptrlen data = bufchain_prefix(s->user_input);
Make bufchain_prefix return a ptrlen. Now that all the call sites are expecting a size_t instead of an int length field, it's no longer particularly difficult to make it actually return the pointer,length pair in the form of a ptrlen. It would be nice to say that simplifies call sites because those ptrlens can all be passed straight along to other ptrlen-consuming functions. Actually almost none of the call sites are like that _yet_, but this makes it possible to move them in that direction in future (as part of my general aim to migrate ptrlen-wards as much as I can). But also it's just nicer to keep the pointer and length together in one variable, and not have to declare them both in advance with two extra lines of boilerplate.
2019-02-06 20:46:45 +00:00
if (data.len > 512)
data.len = 512;
sshfwd_write(&s->mainchan_sc, data.ptr, data.len);
Localise user_input to SSH connection layers. Now that the SSH backend's user_input bufchain is no longer needed for handling userpass input, it doesn't have to be awkwardly shared between all the packet protocol layers any more. So we can turn the want_user_input and got_user_input methods of PacketProtocolLayer into methods of ConnectionLayer, and then only the two connection layers have to bother implementing them, or store a pointer to the bufchain they read from.
2021-09-14 13:00:05 +00:00
bufchain_consume(s->user_input, data.len);
Rewrite the SSH-1 main shell session using mainchan. In SSH-1, the channel system isn't rich enough to represent the complicated main shell session, so it's all done with a separate set of custom message types. But PuTTY now abstracts away that difference, by representing both as different implementations of the SshChannel class: ssh1channel is for things that the protocol thinks are 'really' channels, and ssh1mainchan is for the shell session. All the same methods are implemented, but generate different wire messages. This means that the logic to decide _when_ to enable X forwarding, agent forwarding etc is all centralised into mainchan.c, where it doesn't have to be repeated for both protocol versions. It also simplifies the final loop in the connection protocol, which no longer has to contain the code to move data from the user input bufchain to the channel's output; that's now done by the mainchan write method, the same as it is in SSH-2 where mainchan is just like other channels.
2018-09-30 10:22:01 +00:00
}
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
}
static void ssh1_connection_reconfigure(PacketProtocolLayer *ppl, Conf *conf)
{
struct ssh1_connection_state *s =
Rename FROMFIELD to 'container_of'. Ian Jackson points out that the Linux kernel has a macro of this name with the same purpose, and suggests that it's a good idea to use the same name as they do, so that at least some people reading one code base might recognise it from the other. I never really thought very hard about what order FROMFIELD's parameters should go in, and therefore I'm pleasantly surprised to find that my order agrees with the kernel's, so I don't have to permute every call site as part of making this change :-)
2018-10-05 22:49:08 +00:00
container_of(ppl, struct ssh1_connection_state, ppl);
Move most of ssh.c out into separate source files. I've tried to separate out as many individually coherent changes from this work as I could into their own commits, but here's where I run out and have to commit the rest of this major refactoring as a big-bang change. Most of ssh.c is now no longer in ssh.c: all five of the main coroutines that handle layers of the SSH-1 and SSH-2 protocols now each have their own source file to live in, and a lot of the supporting functions have moved into the appropriate one of those too. The new abstraction is a vtable called 'PacketProtocolLayer', which has an input and output packet queue. Each layer's main coroutine is invoked from the method ssh_ppl_process_queue(), which is usually (though not exclusively) triggered automatically when things are pushed on the input queue. In SSH-2, the base layer is the transport protocol, and it contains a pair of subsidiary queues by which it passes some of its packets to the higher SSH-2 layers - first userauth and then connection, which are peers at the same level, with the former abdicating in favour of the latter at the appropriate moment. SSH-1 is simpler: the whole login phase of the protocol (crypto setup and authentication) is all in one module, and since SSH-1 has no repeat key exchange, that setup layer abdicates in favour of the connection phase when it's done. ssh.c itself is now about a tenth of its old size (which all by itself is cause for celebration!). Its main job is to set up all the layers, hook them up to each other and to the BPP, and to funnel data back and forth between that collection of modules and external things such as the network and the terminal. Once it's set up a collection of packet protocol layers, it communicates with them partly by calling methods of the base layer (and if that's ssh2transport then it will delegate some functionality to the corresponding methods of its higher layer), and partly by talking directly to the connection layer no matter where it is in the stack by means of the separate ConnectionLayer vtable which I introduced in commit 8001dd4cb, and to which I've now added quite a few extra methods replacing services that used to be internal function calls within ssh.c. (One effect of this is that the SSH-1 and SSH-2 channel storage is now no longer shared - there are distinct struct types ssh1_channel and ssh2_channel. That means a bit more code duplication, but on the plus side, a lot fewer confusing conditionals in the middle of half-shared functions, and less risk of a piece of SSH-1 escaping into SSH-2 or vice versa, which I remember has happened at least once in the past.) The bulk of this commit introduces the five new source files, their common header sshppl.h and some shared supporting routines in sshcommon.c, and rewrites nearly all of ssh.c itself. But it also includes a couple of other changes that I couldn't separate easily enough: Firstly, there's a new handling for socket EOF, in which ssh.c sets an 'input_eof' flag in the BPP, and that responds by checking a flag that tells it whether to report the EOF as an error or not. (This is the main reason for those new BPP_READ / BPP_WAITFOR macros - they can check the EOF flag every time the coroutine is resumed.) Secondly, the error reporting itself is changed around again. I'd expected to put some data fields in the public PacketProtocolLayer structure that it could set to report errors in the same way as the BPPs have been doing, but in the end, I decided propagating all those data fields around was a pain and that even the BPPs shouldn't have been doing it that way. So I've reverted to a system where everything calls back to functions in ssh.c itself to report any connection- ending condition. But there's a new family of those functions, categorising the possible such conditions by semantics, and each one has a different set of detailed effects (e.g. how rudely to close the network connection, what exit status should be passed back to the whole application, whether to send a disconnect message and/or display a GUI error box). I don't expect this to be immediately perfect: of course, the code has been through a big upheaval, new bugs are expected, and I haven't been able to do a full job of testing (e.g. I haven't tested every auth or kex method). But I've checked that it _basically_ works - both SSH protocols, all the different kinds of forwarding channel, more than one auth method, Windows and Linux, connection sharing - and I think it's now at the point where the easiest way to find further bugs is to let it out into the wild and see what users can spot.
2018-09-24 17:28:16 +00:00
conf_free(s->conf);
s->conf = conf_copy(conf);
if (s->portfwdmgr_configured)
portfwdmgr_config(s->portfwdmgr, s->conf);
}
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