On OpenSSL versions prior to 1.1.0, `EVP_CIPHER_CTX_cleanup` will
dereference its argument regardless of whether it is NULL. This
is not a problem on OpenSSL at or beyond 1.1.0, where
`EVP_CIPHER_CTX_cleanup` (macro to `EVP_CIPHER_CTX_reset`) returns
early upon NULL input.
Move the call to `EVP_CIPHER_CTX_cleanup` under the existing NULL
check in `evp_cipher_cleanup` to avoid the problem.
Introduced with this build-break fix:
* e66f370682
Found in manual testing in an environment with an older OpenSSL.
Signed-off-by: Jon Simons <jon@jonsimons.org>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
With this change, a HAVE_LIBCRYPTO #ifdef is removed from wrapper.c.
Now, the libcrypto-specific logic for EVP_CIPHER_CTX_free is moved
into the ssh_cipher_struct cleanup callback handler for those
ciphers.
Signed-off-by: Jon Simons <jon@jonsimons.org>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
Fix a resource leak in `hmac_final`: say `HMAC_CTX_free` instead
of `HMAC_CTX_reset`. This matches the error handling as done in
`hmac_init`. Introduced with cf1e808e2f.
The problem is reproducible running the `pkd_hello` test with:
valgrind --leak-check=full ./pkd_hello -i1 -t torture_pkd_openssh_dsa_rsa_default
Resolves https://red.libssh.org/issues/252.
Signed-off-by: Jon Simons <jon@jonsimons.org>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
This has been made opaque and it needs to be a pointer.
This is for OpenSSL 1.1.0 support.
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
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.
