A proxyjump callback structure consists of three callbacks
as of this writing: before_connection, authenticate and
verify_knownhost. One or more of these callbacks can be
set as NULL by the user to indicate that libssh should use
the defaults.
The code checked the presence of the callback stucture but
not whether before_connection was available or not (non NULL)
before dereferencing it.
This could lead to undefined behaviour if the user specifies
say authenticate and verify_knownhost for a jump host but not
before_connection.
This commit fixes the code to add a check for before_connection
being non NULL before trying access it.
Signed-off-by: Eshan Kelkar <eshankelkar@galorithm.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
(cherry picked from commit 26b9ba5f8c)
When `known_hosts` file contained matching valid entry followed by
invalid entry, the first record was already allocated in
`ssh_known_hosts_read_entries()`, but not freed on error.
This could cause possible memory leaks in client, but we do not
consider them as security relevant as the leaks do not add up and
successful exploitaition is hard or impossible.
Originally reported by Kang Yang.
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Norbert Pocs <norbertpocs0@gmail.com>
(cherry picked from commit 1525ea3dda)
The `first` is intialized to -1 and if we reach this without setting this, we
needlessly call close(-1). It should be no-op, but better be safe.
Thanks coverity!
CID 1644001
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
(cherry picked from commit c9abf5ebbb)
... file, even if it was already set before. The options
level handles what was already set.
The proxyJump implementation sets the username from the proxyjump, which
is setting it to NULL, effectively writing the current username to the
new session, which was not possible to override due to the following check.
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
(cherry picked from commit 320844669a)
When the first key object is a certificate object, this match will
fall through to the generic key comparison that is unable to handle
the ed25519 keys and fails.
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
(cherry picked from commit 38f3d158f6)
... and prevent memory leak of host_port on memory allocation failure.
Thanks Xiaoke Wang for the report!
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Pavol Žáčik <pzacik@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
(cherry picked from commit 9d6df9d0fa)
When reusing session structures for multiple
connections, the packet state could be SIZE_READ
before disconnect, causing initial packets of the
next connection to be misinterpreted.
Signed-off-by: Pavol Žáčik <pzacik@redhat.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
(cherry picked from commit 41b8b3326c)
As it may a cause a use after free if `send` fails when
ssh_poll_ctx_dopoll does its callback
ssh_poll_ctx_dopoll still wants to use the poll object later
Signed-off-by: Philippe Antoine <p.antoine@catenacyber.fr>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
(cherry picked from commit c99261437f)
The spread out initialization and variable definition (and alising)
was hell to keep up with and was causing memory issues as reported by valgrind:
==4480== 128 bytes in 1 blocks are definitely lost in loss record 1 of 12
==4480== at 0x48463F3: calloc (vg_replace_malloc.c:1675)
==4480== by 0x487D152: mbedtls_mpi_grow (bignum.c:218)
==4480== by 0x487D6C5: mbedtls_mpi_copy (bignum.c:334)
==4480== by 0x48B9627: mbedtls_rsa_export (rsa.c:899)
==4480== by 0x283955: pki_key_to_blob (pki_mbedcrypto.c:976)
==4480== by 0x24F162: ssh_pki_export_privkey_blob (pki.c:2188)
==4480== by 0x278001: ssh_pki_openssh_privkey_export (pki_container_openssh.c:546)
==4480== by 0x24D7D2: ssh_pki_export_privkey_file_format (pki.c:1122)
==4480== by 0x24D916: torture_pki_rsa_write_privkey_format (torture_pki_rsa.c:895)
==4480== by 0x24D916: torture_pki_rsa_write_privkey (torture_pki_rsa.c:962)
==4480== by 0x4865499: ??? (in /usr/lib64/libcmocka.so.0.8.0)
==4480== by 0x4865C0B: _cmocka_run_group_tests (in /usr/lib64/libcmocka.so.0.8.0)
==4480== by 0x252115: torture_run_tests (torture_pki_rsa.c:1160)
==4480== by 0x2546B8: main (torture.c:1984)
==4480==
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Eshan Kelkar <eshankelkar@galorithm.com>
(cherry picked from commit 6d2a3e4eb6)
See libssh-mirror#311 for background. But in some case, it's possible to
trigger the code in ssh_handle_key_exchange() to move session state
directly to SSH_SESSION_STATE_AUTHENTICATED. The exit condition for this
function is SSH_SESSION_STATE_AUTHENTICATING though, so when it happens,
ssh_handle_key_exchange() will time out eventually.
The fix is straightforward. Tested with the problematic
client (trilead-ssh2) and made sure the bad condition happened (and not
cause timeout)
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
(cherry picked from commit 168302b9d6)
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>
On 32b architecture when processing the SFTP packets, the value
0x7ffffffc in the payload_len will overflow to negative integer values,
causing these checks to pass and possibly reading behind the buffer
bounds later.
This affects only SFTP server implementations running on 32b
architecture.
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
Set maximum input to 256MB to have safe margin to the 1GB trigger point
for 32b arch.
The OOB should not be reachable by any internal code paths as most of
the buffers and strings we use as input for this operation already have
similar limit and none really allows this much of data.
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
(cherry picked from commit 00f09acbec)
Some SFTP servers (Cisco) do not implement the v3 protocol correctly and do not
send the mandatory part of the status message. This falls back to the v2
behavior when the error message and language tag are not provided.
Fixes: #272
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Sahana Prasad <sahana@redhat.com>
(cherry picked from commit 0306581f1c)
