Commit Graph

228 Commits

Author SHA1 Message Date
Jakub Jelen
dc45b8f3f1 channels: Improve logging information about channels
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2025-10-01 16:04:56 +02:00
Rémi Coulom
8069679033 remove unused ssh_string in ssh_channel_open_forward_unix
Signed-off-by: Rémi Coulom <remi.coulom@gmail.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2025-07-25 19:52:37 +02:00
Jakub Jelen
2eb2af4426 CVE-2025-4878 Initialize pointers where possible
This is mostly mechanical change initializing all the pointers I was able to
find with some grep and manual review of sources and examples.

Used the following greps (which yield some false positives though):

    git grep "    \w* *\* *\w*;$"
    git grep " ssh_session \w*;"
    git grep " ssh_channel \w*;"
    git grep " struct ssh_iterator \*\w*;"
    git grep " ssh_bind \w*;"
    git grep " ssh_key \w*;"
    git grep " ssh_string \w*;"
    git grep " ssh_buffer \w*;"
    git grep " HMACCTX \w*;"
    git grep " SHACTX \w*;"
    grep -rinP '^(?!.*=)\s*(?:\w+\s+)*\w+\s*\*\s*\w+\s*;'

Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2025-06-23 15:24:30 +02:00
Jakub Jelen
c799a18d89 channels: Reformat
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2025-06-23 13:48:16 +02:00
Jakub Jelen
d00f7b1bf9 Make sure we pass right parameters to buffer_pack
Fixes: #299

Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Sahana Prasad <sahana@redhat.com>
Reviewed-by: Norbert Pocs <norbertpocs0@gmail.com>
2025-04-15 16:15:52 +02:00
RaviRaaja
04a58919f8 Fix: NULL pointer check in ssh_channel_is_closed
The ssh_channel_is_closed function would crash when
accessing channel->session->alive if session is NULL.
This patch adds a null check before accessing the session
pointer.

- build succeeded
- unit test passed
- no new unit test added

https://gitlab.com/libssh/libssh-mirror/-/issues/239

Signed-off-by: Raviraaja Lakshmanan <mailstoraviraaja@gmail.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2025-04-14 22:20:35 +02:00
Jakub Jelen
b7018c17c7 Fix implicit type conversions and warnings on windows builds
The visual studio windows builds spit dozens of lines of warnings
on these.

Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2025-01-03 15:18:53 +01:00
Jakub Jelen
79ba546cde channels: Remove callbacks from freed channels
When the user frees the channel, they no longer expect any callbacks
to be triggered on it. When we delay the close before we receive
the remaining messages, we should not trigger the user callbacks
as it might be already freed.

I believe this is the random torture_session test failures and
errors we are getting from valgrind from time to time.

We keep the callbacks cleanup in the do_cleanup() in case the
calling application sets the callback after free for some reason.

Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2024-12-20 15:09:54 +01:00
Jakub Jelen
0ea982d4ec channels: Warn against executing multiple commands in single channel
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2024-12-20 15:09:54 +01:00
Liu Husong
2d3b7e07af fix: sftp_packet_read stuck in an infinite loop in blocking mode
Signed-off-by: Liu Husong <huliu@janestreet.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Eshan Kelkar <eshankelkar@galorithm.com>
2024-07-01 13:22:35 +00:00
JamesWrigley
6c59d975ba Poll the channel in ssh_channel_poll() when the buffer isn't empty
Previously the call to ssh_handle_packets() would be skipped if the buffer
wasn't empty. This meant that if ssh_channel_poll() was called on a non-blocking
channel with callbacks to handle incoming data, and the buffer already had some
data, the callbacks would never be called.

Signed-off-by: James Wrigley <james@puiterwijk.org>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2024-06-13 21:11:39 +02:00
Andreas Schneider
04d86aeeae channels: Implement better ssh_channel_get_exit_state() variant
This way we will get errors as return code else we don't know if the
function failed (SSH_ERROR) or the exit_status is -1 which would
correspond to SSH_ERROR.

Signed-off-by: Andreas Schneider <asn@cryptomilk.org>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2024-05-13 15:41:54 +02:00
Andreas Schneider
d40a6448a4 channels: Store exit-signal in channel structure
Signed-off-by: Andreas Schneider <asn@cryptomilk.org>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2024-05-13 15:41:54 +02:00
Andreas Schneider
fdf8dc2750 channels: Reformat SSH_PACKET_CALLBACK(channel_rcv_request)
Signed-off-by: Andreas Schneider <asn@cryptomilk.org>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2024-05-13 15:41:54 +02:00
Andreas Schneider
b2d3a4670a channels: Use a structure to store exit information
Signed-off-by: Andreas Schneider <asn@cryptomilk.org>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2024-05-13 15:41:54 +02:00
Andreas Schneider
bc1acb5312 channels: Make exit_status and uint32_t
This is what we get in the packet and is defined in RFC4254.

Signed-off-by: Andreas Schneider <asn@cryptomilk.org>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2024-05-13 15:41:54 +02:00
Andreas Schneider
3ce68badca channels: Reformat ssh_channel_exit_status_termination()
Signed-off-by: Andreas Schneider <asn@cryptomilk.org>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2024-05-13 15:41:54 +02:00
Daniel Evers
cd6e84a6c3 Issue #157: Use the current TTY's settings by default.
When opening a PTY on the server, try to use the current TTY's settings
(i.e. based on STDIN). If that fails or STDIN isn't a TTY, use default
modes that avoid any character translation.

Don't rely on stdin to be a TTY (breaks CI). Instead, open a PTY and
temporarily use that as "fake" stdin.

Signed-off-by: Daniel Evers (daniel.evers@utimaco.com)
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2024-03-06 14:01:36 +01:00
Daniel Evers
1291ceb17d Fix #157: Allow to set terminal modes for PTYs
Added the new function `ssh_channel_request_pty_size_modes` which allows
to pass additional encoded SSH terminal modes (see opcodes in RFC 4245).

Signed-off-by: Daniel Evers (daniel.evers@utimaco.com)
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2024-03-06 14:01:36 +01:00
JamesWrigley
8fbb12eddf Document that ssh_channel_read_nonblocking() will trigger callbacks
Signed-off-by: James Wrigley <james@puiterwijk.org>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Norbert Pocs <norbertpocs0@gmail.com>
2024-01-02 16:58:47 +01:00
JamesWrigley
a5cc515f02 Document that ssh_channel_read_nonblocking() may return SSH_EOF
The current documentation incorrectly states that it will return 0 on EOF, but
the function calls ssh_channel_poll() internally, which will return SSH_EOF,
which will then be returned by ssh_channel_read_nonblocking().

Signed-off-by: James Wrigley <james@puiterwijk.org>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Norbert Pocs <norbertpocs0@gmail.com>
2024-01-02 16:58:47 +01:00
Tom Deseyn
6a64f5a11a Allow sending data payloads of remote_maxpacket length.
Signed-off-by: Tom Deseyn <tom.deseyn@gmail.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2023-09-08 08:48:40 +02:00
Tom Deseyn
60db508054 channel: use a larger window size to increase receive throughput.
The window size controls how much data the peer can send before
we send back a message to to increase the window.

This changes the default window from 1.28MB to 2MiB. 2MiB matches
the OpenSSH default session size.

The code is also refactored to grow the windows on code paths
where data is consumed, and move the condition that checks
if the growing the window is needed into the grow method.

Signed-off-by: Tom Deseyn <tom.deseyn@gmail.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2023-09-01 19:32:12 +02:00
Jakub Jelen
00bafe0a82 channels: Do not be so picky about the extended data type
assume stderr by default and log only warning in case the data type is
non-standard.

Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Sahana Prasad <sahana@redhat.com>
Reviewed-by: Norbert Pocs <npocs@redhat.com>
2023-08-07 11:08:03 +02:00
Jakub Jelen
d0ffe917fb channels: Fix reading stderr from channels
broken in 4b8db203b0

Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Sahana Prasad <sahana@redhat.com>
Reviewed-by: Norbert Pocs <npocs@redhat.com>
2023-08-07 11:08:03 +02:00
Jakub Jelen
9c19ba7f33 channels: Avoid out-of-bounds writes
CID 1470005

Thanks coverity

Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Norbert Pocs <npocs@redhat.com>
2023-06-28 12:14:44 +02:00
Jakub Jelen
4b8db203b0 channels: Refactor channel_rcv_data, check for errors and report more useful errors
CID 1513157

Thanks coverity

Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Sahana Prasad <sahana@redhat.com>
2023-06-22 17:29:39 +02:00
Jakub Jelen
a45b9938fe channels: Reformat channel_rcv_change_window
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Sahana Prasad <sahana@redhat.com>
2023-06-20 15:20:01 +02:00
Tom Deseyn
6f029598c7 Emit channel_write_wontblock when remote window becomes non-zero.
Signed-off-by: Tom Deseyn <tom.deseyn@gmail.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2023-04-14 15:02:03 +02:00
Norbert Pocs
b7c1f792cc documentation: Fix Missing param doxygen warnings
Signed-off-by: Norbert Pocs <npocs@redhat.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2023-02-01 15:26:02 +01:00
Tom Deseyn
f297dc6ab8 Add callbacks for channel open response, and channel request response.
Signed-off-by: Tom Deseyn <tom.deseyn@gmail.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2023-01-02 16:29:55 +01:00
Jakub Jelen
97c9ac2f58 Fix various spelling issues reported by codespell
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
2022-10-12 13:50:38 +02:00
Xiang Xiao
e4d4ca78b4 remove the unnecessary cast of SSH_LOG
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2022-10-12 11:50:47 +02:00
Xiang Xiao
787735098f change the format specifier of uint32_t from PRId32 to PRIu32
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2022-10-12 11:50:46 +02:00
Xiang Xiao
b53d0608b6 fix printf format warning
uint32_t should be formated by PRI?32

Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Change-Id: I811cfd764010f9e8bb599b370155ac065ee1905c
2022-10-12 11:50:45 +02:00
Norbert Pocs
657d9143d1 SSH_LOG_DEBUG: Recategorize loglevels
Loglevel INFO is the default openssh configuration setting which does not print
redundant information. On a system using openssh with loglevels set by the
terms of openssh will cause unwanted log lines in the output.
recategorized based on - SSH_LOG_DEBUG are informational debug logs (no error)

Signed-off-by: Norbert Pocs <npocs@redhat.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2022-10-07 09:13:19 +02:00
Norbert Pocs
7ea75cda45 SSH_LOG_TRACE: Recategorize loglevels
Do not print out logs when no fatal error happens.
This approach is similiar to openssh, when Error/Fatal does not print
recoverable error logs.
recategorized based on - SSH_LOG_TRACE are debug logs when error happens

Signed-off-by: Norbert Pocs <npocs@redhat.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2022-10-07 09:13:19 +02:00
Norbert Pocs
442599f0d1 Fix type mismatch warnings
Signed-off-by: Norbert Pocs <npocs@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2022-06-15 14:47:06 +02:00
Jakub Jelen
7bd850ab36 Remove bogus semicolons
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2022-06-09 09:08:02 +02:00
Sahana Prasad
4b3a6342db Deprecate duplicate/ unused functions
and fix obvious naming mistakes, mostly in documentation

Signed-off-by: Sahana Prasad <sahana@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2022-06-09 09:08:02 +02:00
Jakub Jelen
2aa137947a Reformat most of the function headers
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2022-06-09 09:08:02 +02:00
Jakub Jelen
daabd78742 Remove remaining mentions of SSH-v1 protocol
also remove anything mentioning limitation to SSHv2 as it is the only
protocol supported these days.

Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2022-06-09 09:08:02 +02:00
Jakub Jelen
1d238694e7 Improve documentation by mentioning the free functions
Related: https://gitlab.com/libssh/libssh-mirror/-/issues/3
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2022-06-09 09:08:02 +02:00
Tomas Holmqvist
dd318aa1a1 channels: Add originator to ssh_channel_accept
Added API function ssh_channel_open_forward_port that is the same as
ssh_channel_accept_forward with the addition to determine the
originator address and port

Signed-off-by: Tomas Holmqvist <tomhol@gmail.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2022-06-07 14:16:59 +02:00
Junda Ai
41e2d17119 Fix multiple spelling and grammar mistakes
Signed-off-by: Junda Ai <aijunda29@gmail.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2022-05-02 19:05:51 +02:00
Jakub Jelen
f2f680aede channels: Avoid memory leak
Thanks oss-fuzz:

https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=40116

Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2021-11-02 11:14:26 +01:00
Artyom V. Poptsov
1ab2340644 channels: Fix segfaults when the channel data is freed
Calling some channel procedures on a freed channel is always resulting
in segmentation fault errors.  The reason is that when a channel is
freed with 'ssh_channel_do_free' procedure, its 'session' field is set
to NULL; then when a channel procedure tries to access any field of
'channel->session' structure it is effectively dereferencing a NULL
pointer.

The change fixes that behavior by adding a check which ensures that a
channel state is not SSH_CHANNEL_FLAG_FREED_LOCAL before accessing its
parent session.

Also the test suite is updated to check for the fixed errors, and the
Doxygen documentation updated accordingly.

There was a bug introduced in b0fb7d15: 'ssh_channel_poll',
'ssh_channel_poll_timeout' and 'ssh_channel_get_exit_status' would
compare the channel state to the 'SSH_CHANNEL_FLAG_FREED_LOCAL'
constant to check if the channel is alive.  But the procedures must
check the channel flags for the presence of
'SSH_CHANNEL_FLAG_FREED_LOCAL' bits instead.  This change fixes the
bug.

Signed-off-by: Artyom V. Poptsov <poptsov.artyom@gmail.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2021-09-15 11:04:45 +02:00
Jeremy Cross
d1abe26be3 [#48/T22] Added missing server reply on auth-agent-req when a reply was requested by the client. PuTTY for Windows chokes without this reply if "Allow agent forwarding" is enabled. Reply will be successful if channel_auth_agent_req_function callback is defined. Based on an unmerged patch by Jon Simons.
Signed-off-by: Jeremy Cross <jcross@beyondtrust.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2021-07-07 14:17:07 +02:00
Xiang Xiao
3ab17e3fbd channels: Read into buffer directly in channel_read_buffer
to avoid allocate 8KB buffer from stack

Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Change-Id: Ifc198705cb8ecec6f0a609f84965382dc151693b
2021-05-27 13:45:47 +02:00
Xiang Xiao
07245c1cdd Fix error: dereferencing pointer to incomplete type ‘struct timeval’
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Change-Id: I99d2016595966d805c9e27b5c2f2a0a5b4ad8611
2021-05-27 13:45:47 +02:00