At least on systems providing SetDefaultDllDirectories, this should
stop PuTTY from being willing to load DLLs from its containing
directory - which makes no difference when it's been properly
installed (in which case the application dir contains no DLLs anyway),
but does if it's being run from somewhere uncontrolled like a browser
downloads directory.
Preliminary testing suggests that this shouldn't break any existing
deliberate use of DLLs, including GSSAPI providers.
We also have the special-purpose -DUNPROTECT to disable just the ACL
changes, but if you want to compile without any Windows security API
support at all (e.g. experimentally building against winelib) then
it's easier not to have to specify both defines separately.
Protecting our processes from outside interference need not be limited
to just PuTTY: there's no reason why the other SSH-speaking tools
shouldn't have the same treatment (PSFTP, PSCP, Plink), and PuTTYgen
and Pageant which handle private key material.
TOOLTYPE_NONNETWORK (i.e. pterm) already has "-log" (as does Unix
PuTTY), so there's no sense suppressing the synonym "-sessionlog".
Undocumented lacunae that remain:
plink accepts -sessionlog, but does nothing with it. Arguably it should.
puttytel accepts -sshlog/-sshrawlog (and happily logs e.g. Telnet
negotiation, as does PuTTY proper).
A Plink invocation of the form 'plink -shareexists <session>' tests
for a currently live connection-sharing upstream for the session in
question. <session> can be any syntax you'd use with Plink to make the
actual connection (a host/port number, a bare saved session name,
-load, whatever).
I envisage this being useful for things like adaptive proxying - e.g.
if you want to connect to host A which you can't route to directly,
and you might already have a connection to either of hosts B or C
which are viable proxies, then you could write a proxy shell script
which checks whether you already have an upstream for B or C and goes
via whichever one is currently active.
Testing for the upstream's existence has to be done by actually
connecting to its socket, because on Unix the mere existence of a
Unix-domain socket file doesn't guarantee that there's a process
listening to it. So we make a test connection, and then immediately
disconnect; hence, that shows up in the upstream's event log.
Having found a lot of unfixed constness issues in recent development,
I thought perhaps it was time to get proactive, so I compiled the
whole codebase with -Wwrite-strings. That turned up a huge load of
const problems, which I've fixed in this commit: the Unix build now
goes cleanly through with -Wwrite-strings, and the Windows build is as
close as I could get it (there are some lingering issues due to
occasional Windows API functions like AcquireCredentialsHandle not
having the right constness).
Notable fallout beyond the purely mechanical changing of types:
- the stuff saved by cmdline_save_param() is now explicitly
dupstr()ed, and freed in cmdline_run_saved.
- I couldn't make both string arguments to cmdline_process_param()
const, because it intentionally writes to one of them in the case
where it's the argument to -pw (in the vain hope of being at least
slightly friendly to 'ps'), so elsewhere I had to temporarily
dupstr() something for the sake of passing it to that function
- I had to invent a silly parallel version of const_cmp() so I could
pass const string literals in to lookup functions.
- stripslashes() in pscp.c and psftp.c has the annoying strchr nature
I don't think anyone has ever actually called it that, colloquially
_or_ formally, and if anyone ever did (in a bug report, say) I'd
probably have to stop and think to work out what they meant. It's
universally called Plink, and should be officially so as well :-)
I'm not actually sure why we've always had back ends notify ldisc of
changes to echo/edit settings by giving ldisc_send(ldisc,NULL,0,0) a
special meaning, instead of by having a separate dedicated notify
function with its own prototype and parameter set. Coverity's recent
observation that the two kinds of call don't even have the same
requirements on the ldisc (particularly, whether ldisc->term can be
NULL) makes me realise that it's really high time I separated the two
conceptually different operations into actually different functions.
While I'm here, I've renamed the confusing ldisc_update() function
which that special operation ends up feeding to, because it's not
actually a function applying to an ldisc - it applies to a front end.
So ldisc_send(ldisc,NULL,0,0) is now ldisc_echoedit_update(ldisc), and
that in turn figures out the current echo/edit settings before passing
them on to frontend_echoedit_update(). I think that should be clearer.
If (Msg)WaitForMultipleObjects returns WAIT_TIMEOUT, we expect 'next'
to have been initialised. This can occur without having called
run_timers(), if a toplevel callback was pending, so we can't expect
run_timers to have reliably initialised 'next'.
I'm not actually convinced this could have come up in either of the
affected programs (Windows PSFTP and Plink), due to the list of things
toplevel callbacks are currently used for, but it certainly wants
fixing anyway for the future.
Spotted by Coverity.
Both GUI PuTTY front ends have a piece of logic whereby a string is
interpreted as host:port if there's _one_ colon in it, but if there's
more than one colon then it's assumed to be an IPv6 literal with no
trailing port number. This permits the PuTTY command line to take
strings such as 'host', 'host:22' or '[::1]:22', but also cope with a
bare v6 literal such as '::1'.
This logic is also required in the two Plink front ends and in the
processing of CONF_loghost for host key indexing in ssh.c, but was
missing in all those places. Add it.
[originally from svn r10121]
I've gone through everywhere we handle host names / addresses (on
command lines, in PuTTY config, in port forwarding, in X display
names, in host key storage...) and tried to make them handle IPv6
literals sensibly, by using the host_str* functions I introduced in my
previous commit. Generally it's now OK to use a bracketed IPv6 literal
anywhere a hostname might have been valid; in a few cases where no
ambiguity exists (e.g. no :port suffix is permitted anyway)
unbracketed IPv6 literals are also acceptable.
[originally from svn r10120]
The basic strategy is described at the top of the new source file
sshshare.c. In very brief: an 'upstream' PuTTY opens a Unix-domain
socket or Windows named pipe, and listens for connections from other
PuTTYs wanting to run sessions on the same server. The protocol spoken
down that socket/pipe is essentially the bare ssh-connection protocol,
using a trivial binary packet protocol with no encryption, and the
upstream has to do some fiddly transformations that I've been
referring to as 'channel-number NAT' to avoid resource clashes between
the sessions it's managing.
This is quite different from OpenSSH's approach of using the Unix-
domain socket as a means of passing file descriptors around; the main
reason for that is that fd-passing is Unix-specific but this system
has to work on Windows too. However, there are additional advantages,
such as making it easy for each downstream PuTTY to run its own
independent set of port and X11 forwardings (though the method for
making the latter work is quite painful).
Sharing is off by default, but configuration is intended to be very
easy in the normal case - just tick one box in the SSH config panel
and everything else happens automatically.
[originally from svn r10083]
Unix GUI programs should not say 'Fatal Error' in the message box
title, and Plink should not destroy its logging context as a side
effect of printing a non-fatal error. Both appear to have been due to
inattentive cut and paste from the pre-existing fatal error functions.
[originally from svn r10044]
This change attempts to reinstate as a universal property something
which was sporadically true of the ad-hockery that came before
toplevel callbacks: that if there's a _very long_ queue of things to
be done through the callback mechanism, the doing of them will be
interleaved with re-checks of other event sources, which might (e.g.)
cause a flag to be set which makes the next callback decide not to do
anything after all.
[originally from svn r10040]
This is a little like schedule_timer, in that the callback you provide
will be run from the top-level message loop of whatever application
you're in; but unlike the timer mechanism, it will happen
_immediately_.
The aim is to provide a general way to avoid re-entrance of code, in
cases where just _doing_ the thing you want done is liable to trigger
a confusing recursive call to the function in which you came to the
decision to do it; instead, you just request a top-level callback at
the message loop's earliest convenience, and do it then.
[originally from svn r10019]
that the user really ought to know but that are not actually fatal to
continued operation of PuTTY or a single network connection.
[originally from svn r9932]
Well, at least across all command-line tools on both Windows and Unix,
and the GTK apps on Unix too. The Windows GUI apps fundamentally can't
write to standard output and it doesn't seem sensible to use message
boxes for these purposes :-)
[originally from svn r9673]
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]
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]
'Config' in putty.h, which stores all PuTTY's settings and includes an
arbitrary length limit on every single one of those settings which is
stored in string form. In place of it is 'Conf', an opaque data type
everywhere outside the new file conf.c, which stores a list of (key,
value) pairs in which every key contains an integer identifying a
configuration setting, and for some of those integers the key also
contains extra parts (so that, for instance, CONF_environmt is a
string-to-string mapping). Everywhere that a Config was previously
used, a Conf is now; everywhere there was a Config structure copy,
conf_copy() is called; every lookup, adjustment, load and save
operation on a Config has been rewritten; and there's a mechanism for
serialising a Conf into a binary blob and back for use with Duplicate
Session.
User-visible effects of this change _should_ be minimal, though I
don't doubt I've introduced one or two bugs here and there which will
eventually be found. The _intended_ visible effects of this change are
that all arbitrary limits on configuration strings and lists (e.g.
limit on number of port forwardings) should now disappear; that list
boxes in the configuration will now be displayed in a sorted order
rather than the arbitrary order in which they were added to the list
(since the underlying data structure is now a sorted tree234 rather
than an ad-hoc comma-separated string); and one more specific change,
which is that local and dynamic port forwardings on the same port
number are now mutually exclusive in the configuration (putting 'D' in
the key rather than the value was a mistake in the first place).
One other reorganisation as a result of this is that I've moved all
the dialog.c standard handlers (dlg_stdeditbox_handler and friends)
out into config.c, because I can't really justify calling them generic
any more. When they took a pointer to an arbitrary structure type and
the offset of a field within that structure, they were independent of
whether that structure was a Config or something completely different,
but now they really do expect to talk to a Conf, which can _only_ be
used for PuTTY configuration, so I've renamed them all things like
conf_editbox_handler and moved them out of the nominally independent
dialog-box management module into the PuTTY-specific config.c.
[originally from svn r9214]
plink did not cope gracefully with this -- it was not possible to override that
hostname on the command line (attempts at doing so would be treated as part of
the remote command).
Fix this by applying the principle of r7265: if the user didn't explicitly
specify that they wanted to launch the hostname in the default (for instance
with '-load "Default Settings"', we assume they don't want to, and such a
hostname doesn't count when deciding whether to treat a non-option argument as
hostname or command.
[originally from svn r8651]
[r7265 == 5d76e00dac]
[r7266 == 856ed4ae73]
Should be no significant change in behaviour.
(Well, entering usernames containing commas on Plink's command line will be
a little harder now.)
[originally from svn r7628]
Instead of passing -1 to its gotdata and sentdata callbacks on
error, winhandl.c will now pass the negation of the Windows error
number; and the Plink front end will now format that into an error
message and pass it on to the user.
[originally from svn r7416]
[r7415 == 702a92ceb8]
there): `plink host -nc host2:port' causes the SSH connection's main
channel to be replaced with a direct-tcpip connection to the
specified destination. This feature is mainly designed for use as a
local proxy: setting your local proxy command to `plink %proxyhost
-nc %host:%port' lets you tunnel SSH over SSH with a minimum of
fuss. Works on all platforms.
[originally from svn r6823]
in place of making a network connection. This has involved a couple
of minor infrastructure changes:
- New dlg_label_change() function in the dialog.h interface, which
alters the label on a control. Only used, at present, to switch
the Host Name and Port boxes into Serial Line and Speed, which
means that any platform not implementing serial connections (i.e.
currently all but Windows) does not need to actually do anything
in this function. Yet.
- New small piece of infrastructure: cfg_launchable() determines
whether a Config structure describes a session ready to be
launched. This was previously determined by seeing if it had a
non-empty host name, but it has to check the serial line as well
so there's a centralised function for it. I haven't gone through
all front ends and arranged for this function to be used
everywhere it needs to be; so far I've only checked Windows.
- Similarly, cfg_dest() returns the destination of a connection
(host name or serial line) in a text format suitable for putting
into messages such as `Unable to connect to %s'.
[originally from svn r6815]
a serial port backend:
- In order to do simultaneous reading and writing on the same
HANDLE, you must enable overlapped access and pass an OVERLAPPED
structure to each ReadFile and WriteFile call. This would make
sense if it were an optional thing I could do if I wanted to do
the reading and writing in the same thread, but making it
mandatory even if I'm doing them in _different_ threads is just
annoying and arbitrary.
- Serial ports occasionally return length 0 from ReadFile, for no
particularly good reason. Fortunately serial ports also don't
have a real EOF condition to speak of, so ignoring EOFs is
actually a viable response in spite of sounding utterly gross.
Hence, handle_{input,output}_new() now accept a flags parameter,
which includes a flag to enable the OVERLAPPED bureaucracy and a
flag to cause EOFs to be ignored on input handles. The current
clients of winhandl.c do not use either of these.
[originally from svn r6813]
it's NULL. Since we already have one back end (uxpty) which doesn't
in fact talk to a network socket, and may well have more soon, I'm
replacing this TCP/IP-centric function with a nice neutral
`connected' function returning a boolean. Nothing else about its
semantics has currently changed.
[originally from svn r6810]
thread-based approach to stdin and stdout, wraps it in a halfway
sensible API, and makes it a globally available service across all
network tools.
There is no direct functionality enhancement from this checkin:
winplink.c now talks to the new API instead of doing it all
internally, but does nothing different as a result.
However, this should lay the groundwork for several diverse pieces
of work in future: pipe-based ProxyCommand on Windows, a serial port
back end, and (hopefully) a pipe-based means of communicating with
Pageant, which should have sensible blocking behaviour and hence
permit asynchronous agent requests and decrypt-on-demand.
[originally from svn r6797]
abstracted out; replace loops structured around a single interaction
per loop with less tortuous code (fixes: `ki-multiprompt-crash',
`ssh1-bad-passphrase-crash'; makes `ssh2-password-expiry' and
`proxy-password-prompt' easier).
The new interaction abstraction has a lot of fields that are unused in
the current code (things like window captions); this is groundwork for
`gui-auth'. However, ssh.c still writes directly to stderr; that may
want to be fixed.
In the GUI apps, user interaction is moved to terminal.c. This should
make it easier to fix things like UTF-8 username entry, although I
haven't attempted to do so. Also, control character filtering can be
tailored to be appropriate for individual front-ends; so far I don't
promise anything other than not having made it any worse.
I've tried to test this fairly exhaustively (although Mac stuff is
untested, as usual). It all seems to basically work, but I bet there
are new bugs. (One I know about is that you can no longer make the
PuTTY window go away with a ^D at the password prompt; this should be
fixed.)
[originally from svn r6437]
[this svn revision also touched putty-wishlist]
our app-private window messages, which is considerably higher than the
WM_XUSER we arbitrarily chose. (This isn't known to be causing any actual
problems. The fix seems not to have obviously broken anything.)
[originally from svn r6183]
[this svn revision also touched putty-wishlist]
Unix Plink sends everything sensible it can find, and it's fully configurable
from the GUI.
I'm not entirely sure about the precise set of modes that Unix Plink should
look at; informed tweaks are welcome.
Also the Mac bits are guesses (but trivial).
[originally from svn r5653]
[this svn revision also touched putty-wishlist]
* All the PuTTY tools for Windows and Unix now contain the fingerprints of
the Master Keys. The method for accessing them is crude but universal:
a new "-pgpfp" command-line option. (Except Unix PuTTYgen, which takes
"--pgpfp" just to be awkward.)
* Move the key policy discussion from putty-website/keys.html to
putty/doc/pgpkeys.but, and autogenerate the former from the latter.
Also tweak the text somewhat and include the fingerprints of the
Master Keys themselves.
(I've merged the existing autogeneration scripts into a single new
one; I've left the old scripts and keys.html around until such time
as the webmonster reviews the changes and plumbs in the new script;
he should remove the old files then.)
[originally from svn r5524]
[this svn revision also touched putty-website]
