crWaitUntilV(pktin) with plain crReturnV, because those coroutines can
be called back either with a response packet from the channel request
_or_ with NULL by ssh_free meaning 'please just clean yourself up'.
[originally from svn r9927]
warnings about insecure crypto components. The latter may crReturn
(though not in any current implementation, I believe), which
invalidates pktin, which is used by the former.
[originally from svn r9921]
of the GET_32BIT macros and then used as length fields. Missing bounds
checks against zero have been added, and also I've introduced a helper
function toint() which casts from unsigned to int in such a way as to
avoid C undefined behaviour, since I'm not sure I trust compilers any
more to do the obviously sensible thing.
[originally from svn r9918]
since there is a theoretical code path (via the crReturn loop after
asking an interactive question about a host key or crypto algorithm)
on which we can leave and return to do_ssh1_login between allocating
and freeing those keys.
(In practice it shouldn't come up anyway with any of the current
implementations of the interactive question functions, not to mention
the unlikelihood of anyone non-specialist still using SSH-1, but
better safe than sorry.)
[originally from svn r9895]
as specified in RFC 6668. This is not so much because I think it's
necessary, but because scrypt uses HMAC-SHA-256 and once we've got it we
may as well use it.
Code very closely derived from the HMAC-SHA-1 code.
Tested against OpenSSH 5.9p1 Debian-5ubuntu1.
[originally from svn r9759]
RFC 4245 section 7.1 specifies the meaning of the "address to bind"
parameter in a "tcpip-forward" request. "0.0.0.0" and "127.0.0.1" are
specified to be all interfaces and the loopback interface respectively
in IPv4, while "" and "localhost" are the address-family-agnostic
equivalents. Switch PuTTY to using the latter, since it doesn't seem
right to force IPv4.
There's an argument that PuTTY should provide a means of configuring the
address family used for remote forwardings like it does for local ones.
[originally from svn r9668]
First, make absolute times unsigned. This means that it's safe to
depend on their overflow behaviour (which is undefined for signed
integers). This requires a little extra care in handling comparisons,
but I think I've correctly adjusted them all.
Second, functions registered with schedule_timer() are guaranteed to be
called with precisely the time that was returned by schedule_timer().
Thus, it's only necessary to check these values for equality rather than
doing risky range checks, so do that.
The timing code still does lots that's undefined, unnecessary, or just
wrong, but this is a good start.
[originally from svn r9667]
confused if they receive a request followed by immediate EOF, since we
currently send outgoing EOF as soon as we see the incoming one - and
then, when the response comes back from the real SSH agent, we send it
along anyway as channel data in spite of having sent EOF.
To fix this, I introduce a new field for each agent channel which
counts the number of calls to ssh_agentf_callback that are currently
expected, and we don't send EOF on an agent channel until we've both
received EOF and that value drops to zero.
[originally from svn r9651]
move the primary conditions out of them into their callers. Fixes a
crash in 'plink -N', since those functions would be called with a NULL
channel parameter and immediately dereference it to try to get c->ssh.
[originally from svn r9644]
They're only likely to be useful for freeing a coroutine state
structure, in which case there's no need to reset the line number
(since all such coroutines keep their line number in the state
structure) and the state structure pointer is always called "s".
[originally from svn r9632]
In sshfwd_unclean_close(), get ssh2_check_close() to handle sending
SSH_MSG_CHANNEL_CLOSE. That way, it can hold off doing so until any
outstanding channel requests are processed.
Also add event log message for unclean channel closures.
[originally from svn r9631]
crFinish or crFinishV, since they will attempt to write to the
coroutine state variable contained in that structure. Introduced some
new all-in-one macros crFinishFree and crFinishFreeV, and used those
instead. Should fix today's report of a crash just after authentication.
[originally from svn r9630]
Part the first: make sure that all structures describing channel
requests are freed when the SSH connection is freed. This involves
adding a means to ask a response handler to free any memory it holds.
Part the second: in ssh_channel_try_eof(), call
ssh2_channel_check_close() rather than emitting an SSH_MSG_CHANNEL_EOF
directly. This avoids the possibility of closing the channel while a
CHANNEL_REQUEST is outstanding.
Also add some assertions that helped with tracking down the latter
problem.
[originally from svn r9623]
This reduces code size a little and also makes it harder to
accidentally request a reply without putting in place a handler for
it or vice versa.
[originally from svn r9620]
The various setup routines can only receive CHANNEL_SUCCESS or
CHANNEL_FAILURE, so there's no need for the to worry about receiving
anything else. Strange packets will end up in do_ssh2_authconn
instead.
[originally from svn r9619]
Each of the minor start-of-session requests is now dealt with by its own
little co-routine, while the shell/command is done in do_ssh2_authconn()
itself. This eliminates one more round-trip in session setup: PuTTY gets
all the way up to sending a shell request before worrying about any
replies.
[originally from svn r9616]
Now each channel has a queue of arbitrary handlers for those messages,
with anything that sends a CHANNEL_REQUEST with want_reply true pushing
a new entry onto the queue, and a shared handler that dispatches
responses appropriately.
Currently, this is only used for winadj@putty.projects.tartarus.org, but
extending it to cover the initial requests as well shouldn't be too
painful.
[originally from svn r9615]
There's no need to have identical code generating server-to-client and
client-to-server versions of the cipher and MAC lists; a couple of
twice-around loops will do fine.
[originally from svn r9610]
Before, NULL in the dispatch table meant "send to the appropriate one of
do_ssh2_transport() and do_ssh2_authconn()". Now those (via small
shims) are specified directly in the dispatch table, so ssh2_protocol()
is much simpler.
In the process, this has somewhat centralised the handling of gross
server protocol violations. PuTTY will now disconnect with a rude
message when (e.g.) OpenSSH sends us an SSH_MSG_UNIMPLEMENTED when we
try to KEXINIT during authentication.
[originally from svn r9609]
by sending most of the initial SSH_MSG_CHANNEL_REQUEST messages before
waiting for any replies. The initial version of this code was a clever
thing with a two-pass loop, but that got hairy so I went for the simpler
approach of separating the request and reply code and having flags to
keep track of which requests have been sent.
[originally from svn r9599]
winadj@putty.projects.tartarus.org request. Not currently enabled
automatically, but should be usable as a manual workaround.
[originally from svn r9592]
zero but does it in such a way that over-clever compilers hopefully
won't helpfully optimise the call away if you do it just before
freeing something or letting it go out of scope. Use this for
(hopefully) every memset whose job is to destroy sensitive data that
might otherwise be left lying around in the process's memory.
[originally from svn r9586]
calling back->unthrottle), we should immediately call
ssh_process_queued_incoming_data to handle the SSH packets that have
been saved for later functioning while we were throttled. Otherwise,
they'll sit there unhandled until the next call to ssh_gotdata, which
might not be for ages if the server thinks it's waiting for us.
[originally from svn r9523]
already sent SSH2_MSG_CHANNEL_CLOSE, we should not skip the _whole_ of
sshfwd_unclean_close(), only the part about sending
SSH2_MSG_CHANNEL_CLOSE. It's still important to retag the SSH channel
as CHAN_ZOMBIE and clean up its previous data provider.
[originally from svn r9389]
subsidiary network modules like portfwd.c. To be called when the
subsidiary module experiences a socket error: it sends an emergency
CHANNEL_CLOSE (not just outgoing CHANNEL_EOF), and immediately deletes
the local side of the channel. (I've invented a new channel type in
ssh.c called CHAN_ZOMBIE, for channels whose original local side has
already been thrown away and they're just hanging around waiting to
receive the acknowledging CHANNEL_CLOSE.)
As a result of this and the last few commits, I can now run a port
forwarding session in which a local socket error occurs on a forwarded
port, and PuTTY now handles it apparently correctly, closing both the
SSH channel and the local socket and then actually recognising that
it's OK to terminate when all _other_ channels have been closed.
Previously the channel corresponding to the duff connection would
linger around (because of net_pending_errors never being called), and
keep being selected on (hence chewing CPU), and inhibit program
termination at the end of the session (because not all channels were
closed).
[originally from svn r9364]
for which we've already sent CHANNEL_CLOSE. It would be embarrassing
if the remote end had also sent CHANNEL_CLOSE in response and then
received our communication once it had forgotten about the channel.
[originally from svn r9360]
from forwarding data sources which will be good enough to last until
we close the socket, in the form of the override_throttle() functions.
So this finishes up the work in r9283, by manufacturing outgoing EOF
in response to incoming CLOSE on all channel types.
[originally from svn r9284]
[r9283 == c54e228d04]
incoming CHANNEL_CLOSE, if it's the main session channel. The idea is
that invocations such as 'plink -T hostname sh' (running a shell
without a remote pty) can be exited by typing 'exit' to the remote
shell, without plink blocking forever waiting for outgoing EOF.
I think it would be better to do the same for all other channel types
too, but that would need an extra API call which I haven't
implemented yet.
[originally from svn r9283]
backend should unilaterally assume outgoing EOF when it sees incoming
EOF, if and only if the main session channel is talking to a pty.
(Because ptys don't have a strong concept of EOF in the first place,
that seems like a sensible place to draw the line.) This fixes a bug
introduced by today's revamp in which if you used Unix Plink to run a
console session it would hang after you hit ^D - because the server
had sent EOF, but it was waiting for a client-side EOF too.
[originally from svn r9282]
data channels. Should comprehensively fix 'half-closed', in principle,
though it's a big and complicated change and so there's a good chance
I've made at least one mistake somewhere.
All connections should now be rigorous about propagating end-of-file
(or end-of-data-stream, or socket shutdown, or whatever) independently
in both directions, except in frontends with no mechanism for sending
explicit EOF (e.g. interactive terminal windows) or backends which are
basically always used for interactive sessions so it's unlikely that
an application would be depending on independent EOF (telnet, rlogin).
EOF should now never accidentally be sent while there's still buffered
data to go out before it. (May help fix 'portfwd-corrupt', and also I
noticed recently that the ssh main session channel can accidentally
have MSG_EOF sent before the output bufchain is clear, leading to
embarrassment when it subsequently does send the output).
[originally from svn r9279]
