Commit Graph

114 Commits

Author SHA1 Message Date
Aris Adamantiadis
7ecc6a704b CVE-2023-48795: client side mitigation
Signed-off-by: Aris Adamantiadis <aris@0xbadc0de.be>
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2023-12-18 17:35:04 +01:00
Sahana Prasad
adfb2bcc75 Revert the control flow callback in commit
6f029598c7

Signed-off-by: Sahana Prasad <sahana@redhat.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2023-09-08 08:51:45 +02:00
Jakub Jelen
4fb6bccf22 CVE-2023-1667:packet: Do not allow servers to initiate handshake
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Norbert Pocs <npocs@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2023-05-04 11:51:17 +02:00
Jakub Jelen
d6bc4905ad packet: Reformat callback handling functions
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Norbert Pocs <npocs@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2023-05-04 11:51:17 +02:00
Jakub Jelen
1f3143b18c packet: Fix indentation
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Norbert Pocs <npocs@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2023-05-04 11:51:17 +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
Jakub Jelen
19c4de7350 Reformat ssh_packet_socket_callback
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2023-03-09 10:10:18 +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
Carlos Martín Nieto
346e6db318 packet: do not enqueue outgoing packets after sending SSH2_MSG_NEWKEYS
When we decide we need to rekey, we enqueue any further packets until we've sent
our SSH2_MSG_NEWKEYS message, after which we dequeue these packets and send them
to the other side. This enqueueing is done based on ssh_packet_in_rekey checking
the session flags and whether DH handshake state is marked as finished.

However, the handshake state is not reset to DH_STATE_FINISHED until the other
side has sent us their new keys. This leaves a gap between sending our new keys
and receiving the other side's new keys where we would still decide to enqueue a
packet.

These enqueued packets will not be dequeued as we've already sent our new keys.
Once we've received the other side's new keys, we'll go back to a finished
handshake and we will send out our caller's new data, skipping however much data
we've enqueued.

Fix this by changing ssh_packet_in_rekey to return false once we've sent our new
keys.

Signed-off-by: Carlos Martín Nieto <carlosmn@github.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2022-10-07 10:26:38 +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
Andreas Schneider
7bcc2d83a4 packet: Fix ssh_packet_socket_callback() return value
According to the documentation the return value is the number of
processed bytes, so the returned value is never negative. We should not
use ssize_t in public headers as it isn't available on Windows! We only
have it defined in priv.h!

Signed-off-by: Andreas Schneider <asn@cryptomilk.org>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2022-06-22 12:28:30 +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
Dhanuka Warusadura
3084b2bc41 trivial fix: Fixes some spelling errors
Signed-off-by: Dhanuka Warusadura <csx@tuta.io>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2022-04-19 15:55:49 +02:00
Jakub Jelen
f5211239f9 CVE-2021-3634: Create a separate length for session_id
Normally, the length of session_id and secret_hash is the same,
but if we will get into rekeying with a peer that changes preference
of key exchange algorithm, the new secret hash can be larger or
smaller than the previous session_id causing invalid reads or writes.

Resolves https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=35485

Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2021-08-18 14:13:56 +02:00
Dirkjan Bussink
0987e6065c Always check return value of ssh_list_new()
Another item identified during code review was cases where the return
value of ssh_list_new() was not properly checked and handled. This
updates all cases that were missing this to handle failure to allocate a
new list.

Signed-off-by: Dirkjan Bussink <d.bussink@gmail.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2020-12-11 13:35:20 +01:00
Dirkjan Bussink
f6a2f6190c Ignore request success and failure message if they are not expected
In https://gitlab.com/libssh/libssh-mirror/-/merge_requests/145#note_463232084
behavior in libssh was identified where it diverges from how for example
OpenSSH behaves. In OpenSSH if a request success of failure message is
received, apart from it being treated as a keepalive message, it is
ignored otherwise.

Libssh does handle the unexpected message and triggers an error
condition internally. This means that with the Dropbear behavior where
it replies to a hostkeys-00@openssh.com message even with a want_reply
= 0 (arguably a bug), libssh enters an error state.

This change makes the libssh behavior match OpenSSH to ignore these
messages. The spec is a bit unclear on whether Dropbear is buggy here or
not, but let's be liberal with the input accepted here in libssh.

Signed-off-by: Dirkjan Bussink <d.bussink@gmail.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2020-12-11 13:29:46 +01:00
Jakub Jelen
f85464b900 packet: Fix unterminated brace and better context name in debug message
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2020-07-16 12:01:04 +02:00
Jakub Jelen
4f976ce5c4 packet: Skip HMAC handling if none is selected
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2020-05-05 14:23:06 +02:00
Jakub Jelen
239eef6322 packet: Check if set_*_key functions exists before calling it
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2020-05-05 14:23:06 +02:00
Jakub Jelen
201fd66176 packet: Use temporary variables to avoid long lines
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2020-05-05 14:23:06 +02:00
Andreas Schneider
faedadf2eb packet: Replace PRIdS with ANSI C99 %zu
Signed-off-by: Andreas Schneider <asn@cryptomilk.org>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2020-02-12 09:39:06 +01:00
Andreas Schneider
35799bb1c6 packet: Use SSH_BUFFER_FREE()
Fixes T183

Signed-off-by: Andreas Schneider <asn@cryptomilk.org>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2019-12-09 16:08:03 +01:00
Andreas Schneider
53635dff7e packet: Fix size types in ssh_packet_need_rekey()
Fixes T188

Signed-off-by: Andreas Schneider <asn@cryptomilk.org>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2019-12-09 16:08:03 +01:00
Andreas Schneider
e00ef9635a packet: Do not deref a NULL pointer in ssh_packet_set_newkeys()
Fixes T183

Signed-off-by: Andreas Schneider <asn@cryptomilk.org>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2019-11-18 11:59:01 +01:00
Andreas Schneider
e60fc79542 SSH-01-003: Add cipher NULL checks to ssh_packet_get_current_crypto()
Fixes T183

Signed-off-by: Andreas Schneider <asn@cryptomilk.org>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2019-11-18 11:59:01 +01:00
Jakub Jelen
e9e8292370 packet: On failure, do not use uninitialized crypto
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
Reviewed-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
2019-10-25 13:42:07 +02:00
Anderson Toshiyuki Sasaki
6a9185636f packet: Check return value when sending unimplemented
Signed-off-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2019-06-27 10:31:46 +02:00
Anderson Toshiyuki Sasaki
a1ee22eb64 packet: Reformat ssh_packet_process()
Signed-off-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2019-06-27 10:31:46 +02:00
Jon Simons
7ef2fe7f7b packet: log when data-based rekeying needed
Log an SSH_LOG_PACKET debug message when rekeying is necessary due to
the cipher max_blocks configuration.

Signed-off-by: Jon Simons <jon@jonsimons.org>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2019-04-29 14:00:39 +02:00
Dirkjan Bussink
4a67c19118 Add tests and implementation for Encrypt-then-MAC mode
This adds the OpenSSH HMACs that do encrypt then mac. This is a more
secure mode than the original HMAC. Newer AEAD ciphers like chacha20 and
AES-GCM are already encrypt-then-mac, but this also adds it for older
legacy clients that don't support those ciphers yet.

Signed-off-by: Dirkjan Bussink <d.bussink@gmail.com>
Reviewed-by: Jon Simons <jon@jonsimons.org>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2019-02-22 15:31:08 +01:00
Dirkjan Bussink
c6608c9211 Refactor ssh_packet_hmac_verify to allow for direct buffer
This will make it easier to do Encrypt-then-MAC checks as those will be
on the direct encrypted data received before decrypting which means they
are not allocated in an ssh buffer at that point yet.

Signed-off-by: Dirkjan Bussink <d.bussink@gmail.com>
Reviewed-by: Jon Simons <jon@jonsimons.org>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
2019-02-22 15:30:59 +01:00
Andreas Schneider
9b694f396c packet: Add missing error check in packet_send2()
Found by csbuild.

Signed-off-by: Andreas Schneider <asn@cryptomilk.org>
2019-01-26 14:21:46 +01:00
Aris Adamantiadis
574bfb5459 dh-gex: Add client implementation
Signed-off-by: Aris Adamantiadis <aris@0xbadc0de.be>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2019-01-24 11:56:23 +01:00
Aris Adamantiadis
602a1defea kex: use runtime callbacks (client)
Signed-off-by: Aris Adamantiadis <aris@0xbadc0de.be>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2019-01-24 09:11:30 +01:00
Jakub Jelen
7e41d08f26 packet: Dump also the packet type
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2019-01-09 10:31:49 +01:00
Jakub Jelen
58cae2366a packet: Implement rekeying based on the recommendation from RFC's
The default rekeying recommendations are specified in
RFC4344 Section 3 (First and Second Rekeying Recommendations).
Additionally, the rekeying can be specified in configuration
file/options allowing us to turn the rekeying off, base it
on time or make it more strict.

The code is highly inspired by the OpenSSH rekeying code.

Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Daiki Ueno <dueno@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2019-01-09 10:31:49 +01:00
Jakub Jelen
c86a00d06b packet: Provide a function to switch crypto in separate directions
This also fixes the test using the crypto directly

Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Daiki Ueno <dueno@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2019-01-09 10:31:45 +01:00
Jakub Jelen
8e0c047031 packet: Introduce a new function to access crypto
And remove most of the direct access to the structure throughout the code

Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Daiki Ueno <dueno@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2019-01-09 10:14:56 +01:00
Jakub Jelen
836982358a packet: Adjust the packet filter to allow client-initialized rekey
If the rekey is initialized by client, it sends the first KEXINIT
message, changes to the INIT_SENT state and waits for the KEXINIT
message from the server. This was not covered in the current filter.

Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Daiki Ueno <dueno@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2019-01-09 10:14:56 +01:00
Jakub Jelen
a61368a06a packet: Prepare counters to handle rekeying limits
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Daiki Ueno <dueno@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2019-01-09 10:14:56 +01:00
Jakub Jelen
81fdb574e7 packet: Write also incoming packets to .pcap files
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Daiki Ueno <dueno@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2019-01-09 10:14:56 +01:00
Anderson Toshiyuki Sasaki
fe309ba43f packet: Allow SSH2_MSG_EXT_INFO when authenticated
When the server requests rekey, it can send the SSH2_MSG_EXT_INFO.  This
message was being filtered out by the packet filtering.  This includes a
test to enforce the filtering rules for this packet type.

Signed-off-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2018-12-10 16:42:26 +01:00
Jakub Jelen
e639c9d0d8 kex,packet,packet_cb: Reformat
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2018-11-23 17:30:16 +01:00
Aris Adamantiadis
f4339df577 packets: allow removal of callbacks
Signed-off-by: Aris Adamantiadis <aris@0xbadc0de.be>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
2018-11-21 16:54:20 +01:00
Andreas Schneider
8a3ea3bdd5 packet: Do not segfault if we don't have packet_second_block
Signed-off-by: Andreas Schneider <asn@cryptomilk.org>
2018-10-24 09:48:35 +02:00
Andreas Schneider
a190ff9302 packet: Add missing null pointer check in ssh_packet_socket_callback()
Signed-off-by: Andreas Schneider <asn@cryptomilk.org>
2018-10-24 09:48:35 +02:00