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>
These calls can fail and the return code should always be checked. These
issues were identified when code review called it out on new code. The
updates here are to existing code with no behavior changes to make
review simpler.
Signed-off-by: Dirkjan Bussink <d.bussink@gmail.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
In 906cc7e7e9 a memory leak was fixed but
a similar one is present here that needs a fix as well.
Signed-off-by: Dirkjan Bussink <d.bussink@gmail.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
This adds server-side support for the newly introduced OpenSSH
keytypes sk-ecdsa-sha2-nistp256@openssh.com and sk-ed25519@openssh.com
(including their corresponding certificates), which are backed
by U2F/FIDO2 tokens.
Change-Id: Ib73425c572601c3002be45974e6ea051f1d7efdc
Signed-off-by: Sebastian Kinne <skinne@google.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Imports private and public keys from the engine via PKCS11 URIs. Uses
the imported keys to authenticate to the ssh server.
Signed-off-by: Sahana Prasad <sahana@redhat.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
Generally, when the extension negotiation is enabled and client supports
SHA2 algorithms for RSA, they are supposed to be prioritized against the
old SHA1. If it is not (ssh-rsa is listed in front of rsa-sha2-* hostkey
algorithms during negotiation), the server wrongly tries to provide the
new typo of signature, ignoring the negotiated algirithm
This commit propagates the digest algorithm from negotiation to the actual
signature functions, which were previously responsible for decision
about the hash algorithm based just on the negotiated extensions.
Fixes T191
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
This removes unused function pki_signature_verify()
from pki_{crypto, mbedcrypto, gcrypt}. The function was also removed
from include/libssh/pki_priv.h. The function ssh_pki_signature_verify()
was changed to receive a const unsigned char *input.
All tests calling pki_signature_verify() were changed to call
ssh_pki_signature_verify() instead.
Signed-off-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Use OpenSSL to generate and verify Ed25519 signatures, if supported.
Signed-off-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Replace all occurrences of the deprecated function ssh_print_hexa() with
the introduced ssh_log_hexdump().
Signed-off-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
Try to find the OpenSSH private key header not only at the beginning of
the file. This makes the parser to skip comments and white spaces.
Fixes: T76
Fixes: T123
Signed-off-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
When we are talking to old OpenSSH versions which does not support
rsa-sha2-{256,512}-cert-v01@openssh.com or SHA2 in certificates,
fallback to old supported values.
Signed-off-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
When in FIPS mode, filter the algorithms to enable only the allowed
ones. If any algorithm is explicitly set through options or
configuration file, they are kept.
Signed-off-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
Previously when generating the signature in server side the key was
checked against the wrong list, potentially making the server to select
the wrong algorithm to sign (e.g. rsa-sha2-512 instead of rsa-sha2-256).
Signed-off-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Do not allow using SSH_DIGEST_AUTO for any algorithm other than
ed25519.
Do not allow using incompatible hash algorithms when signing or
verifying signatures.
Added negative tests for all combinations of signature and hash
algorithms.
Signed-off-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
This is a preparation to store the raw signature for all algorithms in
the same place in ssh_signature.
Signed-off-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
This makes pki_do_sign() and pki_signature_verify() to receive the
original input instead of the pre-calculated hash. The hash is then
calculated internally.
The hash to be used inside the signature is decided earlier, when all
the information about the signature to be generated/verified is
available.
Simplify ssh_pki_do_sign() and ssh_srv_pki_do_sign_sessionid().
The tests were modified to use pki_do_sign() instead of
pki_do_sign_hash().
Signed-off-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
Refactor ssh_srv_pki_do_sign_sessionid() without behaviour changes.
Signed-off-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
Added ECDSA key types to ssh_key_type_to_hash(). Refactor
ssh_pki_do_sign() without behaviour changes.
Signed-off-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
A number of places checked that the signature type matched the key type. We
losen these checks to, for example, allow an RSA signature with an RSA-cert
key.
Signed-off-by: Ben Toews <mastahyeti@gmail.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Previously, we were just storing the raw certificate in ssh_key->cert. With
this change, we parse out the nonce string at the beginning of the certificate.
This leaves us with the certificate's public key at the start of the buffer.
The existing public key parsing code can then parse this out into the key fieds
of the ssh_key.
Signed-off-by: Ben Toews <mastahyeti@gmail.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
As with RSA/DSS, support is still quite limited. This is mostly about adding
new ssh_keytypes_e values and updating sites that check keys' types.
Signed-off-by: Ben Toews <mastahyeti@gmail.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
This type is imprecise. We often need the ecdsa_nid in addition to the key type
in order to do anything. We replace this singluar ECDSA type with one type per
curve.
Signed-off-by: Ben Toews <mastahyeti@gmail.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
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>
