Add NULL checks to 'is_first_kex_packet_follows_guess_wrong'
to ensure that a 'strdup(NULL)' path can not be taken.
Signed-off-by: Jon Simons <jon@jonsimons.org>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
Ensure to honor the 'first_kex_packet_follow' field when processing
KEXINIT messages in the 'ssh_packet_kexinit' callback. Until now
libssh would assume that this field is always unset (zero). But
some clients may set this (dropbear at or beyond version 2013.57),
and it needs to be included when computing the session ID.
Also include logic for handling wrongly-guessed key exchange algorithms.
Save whether a client's guess is wrong in a new field in the session
struct: when set, the next KEX_DHINIT message to be processed will be
ignored per RFC 4253, 7.1.
While here, update both 'ssh_packet_kexinit' and 'make_sessionid' to
use softabs with a 4 space indent level throughout, and also convert
various error-checking to store intermediate values into an explicit
'rc'.
Patch adjusted from original to ensure that client tests remain passing
(ie 'torture_connect'): restrict the changes in 'ssh_packet_kexinit'
only for the 'server_kex' case.
Signed-off-by: Jon Simons <jon@jonsimons.org>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
Ensure to honor the 'first_kex_packet_follow' field when processing
KEXINIT messages in the 'ssh_packet_kexinit' callback. Until now
libssh would assume that this field is always unset (zero). But
some clients may set this (dropbear at or beyond version 2013.57),
and it needs to be included when computing the session ID.
Also include logic for handling wrongly-guessed key exchange algorithms.
Save whether a client's guess is wrong in a new field in the session
struct: when set, the next KEX_DHINIT message to be processed will be
ignored per RFC 4253, 7.1.
While here, update both 'ssh_packet_kexinit' and 'make_sessionid' to
use softabs with a 4 space indent level throughout, and also convert
various error-checking to store intermediate values into an explicit
'rc'.
Signed-off-by: Jon Simons <jon@jonsimons.org>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
Enable retrieving the "ecdsa-sha2-nistpNNN" name of ECDSA keys with a
new 'ssh_pki_key_ecdsa_name' API. This gives more information than the
'ssh_key_type_to_char' API, which yields "ssh-ecdsa" for ECDSA keys.
The motivation is that this info is useful to have in a server context.
The torture_pki unit test is updated to include the new API, and a few
more passes are added to additionally test 384 and 521-bit keys.
Signed-off-by: Jon Simons <jon@jonsimons.org>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
SSH_BIND_OPTIONS_HOSTKEY will now load host keys of any supported type
rather than set the algorithms that the server permits (which seems
like an unhelpful option anyway; it seems you can always control this
by just loading the right keys).
This option has slightly different semantics than the
SSH_BIND_OPTIONS_<x>KEY options because it requires the key file to
exist immediately rather than on ssh_bind_listen or
ssh_bind_accept_fd. The semantics of this option makes more sense to
me.
We also eliminate ssh_bind_options_set_algo, since it is no longer
used.
Signed-off-by: Alan Dunn <amdunn@gmail.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
In packet_send2, rather than issue two separate buffer_prepend_data calls
(each of which may entail realloc + memmove + memcpy), elide the prepend
work into a single buffer_prepend_data: the header information is computed
locally, and a single 5 byte prepend operation is now done instead of
prepending 1, then 4 bytes.
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
If the sockets are created manually and passed to libssh the internal session
state is set to SSH_SESSION_STATE_SOCKET_CONNECTED. Result of this fix can be
verified by running torture_connect test (torture_connect_socket) with -vvvv
flags.
Signed-off-by: Luka Perkov <luka.perkov@sartura.hr>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
On Mar 16, 09:41, Aris Adamantiadis wrote:
> Hi Petar,
> I agree with the principle, but I don't think this code can work...
> RSA_generate_key takes an RSA* as parameter and in our code we probably
> have key->rsa==NULL. (if we don't then the old code had a memory leak).
>
> Does the test case work ?
>
> Aris
>
Yes, you are right. This works, tested with tests/unittests/torture_pki
Signed-off-by: Petar Koretic <petar.koretic@sartura.hr>
Previously, SHA-1 was used always.
BUG: https://red.libssh.org/issues/148
Signed-off-by: Alan Dunn <amdunn@gmail.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
The commit fixes this build warning:
====
src/server.c:223:8: warning: ‘privkey’ may be used uninitialized in this function [-Wmaybe-uninitialized]
rc = ssh_pki_export_privkey_to_pubkey(*privkey, &pubkey);
^
src/server.c:243:11: note: ‘privkey’ was declared here
ssh_key privkey;
====
Signed-off-by: Luka Perkov <luka.perkov@sartura.hr>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
In 'ssh_bind_listen', move setting of 'sshbind->bindfd' to only happen after
the listen call: otherwise 'bindfd' can be set to a bogus descriptor for the
case that listen fails.
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
When accepting a new connection, a forking server based on libssh forks
and the child process handles the request. The RAND_bytes() function of
openssl doesn't reset its state after the fork, but simply adds the
current process id (getpid) to the PRNG state, which is not guaranteed
to be unique.
This can cause several children to end up with same PRNG state which is
a security issue.
After discussion with Aris and it was not obvious enough to understand
the issue we decided to refactor it.
Reviewd-by: Aris Adamantiadis <aris@0xbadc0de.be>
