Cleanup the KDF function to use only one function per crypto backend.
Improve the KDF function to properly handle requested lenght and to
avoid unnecessarily reallocating buffers.
In OpenSSL use the new EVP_KDF API if available.
Signed-off-by: Simo Sorce <simo@redhat.com>
Reviewed-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
This adds a flag to the type structures to track if we use a
Encrypt-then-MAC cipher instead of Encrypt-and-MAC. EtM is a more secure
hashing mechanism.
Signed-off-by: Dirkjan Bussink <d.bussink@gmail.com>
Reviewed-by: Jon Simons <jon@jonsimons.org>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
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>
This is not supported by OpenSSH and not recommended to be implemented
either.
Signed-off-by: Dirkjan Bussink <d.bussink@gmail.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Buffer (un)packing was broken on compilers that are not
gcc-compatible since the checks for an argument count of
-1 have been removed from ssh_buffer_(un)pack(). This
fix no longer uses GCC extensions for the __VA_NARG__
macro, but only plain C99.
Note: The macro can no longer count empty argument lists
(results in compile error) which was not needed anyway.
Signed-off-by: Tilo Eckert <tilo.eckert@flam.de>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Commit c306a693f3 ("buffer: Use size_t for argc argument in
ssh_buffer_(un)pack()") mentioned unpack in the commit log, but it only
touches the pack variants. Extend the conversion to unpack.
Pre-initialize the p pointer to avoid possible use before
initialization in case of early argc check failure.
This fixes build failure:
.../libssh-0.8.6/src/buffer.c: In function 'ssh_buffer_unpack_va':
.../libssh-0.8.6/src/buffer.c:1229:16: error: assuming signed overflow does not occur when simplifying conditional to constant [-Werror=strict-overflow]
if (argc == -1){
^
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
Ensure most of the abstraction around the 3 libs are consistent.
Signed-off-by: Aris Adamantiadis <aris@0xbadc0de.be>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
If the server had an RSA host key, it provided unconditionally SHA2
signatures without consulting the client proposed list of supported host
keys.
This commit implements more fine-grained detection of the extension
to provide the client with valid signatures according to RFC 8332
Section 3.1.
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
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>
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>
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>
* This makes the array constant in the session structure, avoiding
allocations and frees while parsing the file
* It also drops passing the seen array to all the functions,
because it is already part of the passed session
* The test cases are adjusted to match these changes
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
Initial solution proposed by Tilo Eckert <tilo.eckert@flam.de>
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
ssh_send_keepalive() should use global_request() to properly configure
the state machine for packet filtering.
Signed-off-by: Nicolas Viennot <nicolas@viennot.biz>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
This follows the OpenSSH behavior of parsing subseqent configuration
files, while applying only the first option.
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
This will allow to use the same configuration in client applications
including the users aliases or system wide cryptographic configuration.
As the configuration parsing is the last thing before doing the
actual connection, it might overwrite previously set options.
If this is not intended, the client application can
ask the configuration files to be parsed before setting some other
options that should not ve overwritten. The code ensures that
the configuration is not parsed again.
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
Previously, not all of the host keys algorithms were used for algorithm
negotiation. This verifies the algorithms list is sane and ordered
with the key types from known hosts in the first place.
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
The packet filter checks required states for the incoming packets and
reject them if they arrived in the wrong state.
Fixes T101
Signed-off-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
The introduced auth state allows to identify when a request without
authentication information was sent.
Fixes T101
Signed-off-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
The introduced auth state allows to identify when authentication using
password was tried.
Fixes T101
Signed-off-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
Introduced the states SSH_AUTH_STATE_PUBKEY_OFFER_SENT and
SSH_AUTH_STATE_PUBKEY_AUTH_SENT to know when SSH2_MSG_USERAUTH_PK_OK and
SSH2_MSG_USERAUTH_SUCCESS should be expected.
Fixes T101
Signed-off-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
The commit also propares the internals throughout the code base
for the inclusion of a new AEAD cipher, because previously, the
source code counted only with chacha20-poly1305 cipher, which
is very specific in many cases.
The SSH_HMAC_AEAD_GCM mac algorithm is not actually used, but the name
needed to be defined so we can match in the algorithms selection per
OpenSSH specification (MACs are ignored in case GCM is select as a cipher [1]).
If the provided OpenSSL does not provide EVP_aes_128_gcm() function,
the AES-GCM ciphers will not be compiled in.
[1] https://cvsweb.openbsd.org/src/usr.bin/ssh/PROTOCOL.chacha20poly1305?annotate=HEAD
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
Add support for "hardlink@openssh.com" and
"posix-rename@openssh.com" extensions.
Signed-off-by: Chris Townsend <christopher.townsend@canonical.com>
Signed-off-by: Alberto Aguirre <albaguirre@gmail.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
This implements reading the OpenSSH key format accross the
cryptographic backends. Most of the code is shared and moved
to pki.c, just the building of the keys is implemented in
pki_privkey_build_*() functions.
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
Amends f818e63f8, which introduced the constants and matching of this
configuration option, but did not implement the handling of the values
which was causing the configuration parser failing for certain
configurations.
This commit exposes match_pattern_list() from match.c
Red Hat Bugzilla:
https://bugzilla.redhat.com/show_bug.cgi?id=1624425
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
This involves mostly creation of host keys proofs but needs
to follow the same procedure as the client authentication
signatures.
At the same time, the SHA2 extension is enabled in the pkd
so we are able to atomicaly provide correct signatures and
pass tests.
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
This includes intercepting the ext-info-c string from
the client kex proposal, configuring the server to allow using
this extension and sending the SSH_MSG_EXT_INFO packet back
to the client after the new keys are in use.
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
Verify the PUBLICKEY_ACCEPTED_TYPES option is handled correctly
and affects the signature algorithm selection based on the
extensions and can be used to limit list of offered mechanisms
to the server.
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
This effectively allows to disable using the SHA2 extension, disable
other old public key mechanisms out of the box (hello DSA) or force
the new SHA2-based key algorithm types if needed.
This exposes the default_methods array from kex.c.
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
This option allows to specify acceptable public key algorithms
and reflects the PubkeyAcceptedTypes configuration option from
OpenSSH.
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
The new constants for flags are defined in draft-miller-ssh-agent-02
are active if the SHA2 extension is negotiated with the server.
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
* This change introduces a new API to request signature using
one key and different hash algorithms. This is used only with
RSA keys, that used to have SHA1 hardcoded, but the new
algorithsms allow to use the SHA2 hashes, if the extension
is negotiated.
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
This changes the private API by adding one more argument to function
pki_signature_from_blob()
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
RFC 8308: The extension negotiation in Secure Shell (SSH) Protocol
RFC 8332: Use of RSA Keys with SHA-256 and SHA-512
in the Secure Shell (SSH) Protocol
Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
This changes the condition to use the static error check mutex
initializer. If it is not available, use the default static mutex
initializer.
Signed-off-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
Added Windows threads implementation based on CriticalSection.
Signed-off-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
