Allow passing a PIN via the SK API (API major crank) and let the
ssh-sk-helper API follow.
Also enhance the ssh-sk-helper API to support passing back an error
code instead of a complete reply. Will be used to signal "wrong PIN",
etc.
feedback and ok markus@
OpenBSD-Commit-ID: a1bd6b0a2421646919a0c139b8183ad76d28fb71
The ssh-sk-helper client API gives us a nice place to disable
security key support when it is wasn't enabled at compile time,
so we don't need to check everywere.
Also, verification of security key signatures can remain enabled
all the time - it has no additional dependencies. So sshd can
accept security key pubkeys in authorized_keys, etc regardless of
the host's support for dlopen, etc.
This extracts and refactors the client interface for ssh-sk-helper
from ssh-agent and generalises it for use by the other programs.
This means that most OpenSSH tools no longer need to link against
libfido2 or directly interact with /dev/uhid*
requested by, feedback and ok markus@
OpenBSD-Commit-ID: 1abcd3aea9a7460eccfbf8ca154cdfa62f1dc93f
This is populated during signature verification with additional fields
that are present in and covered by the signature. At the moment, it is
only used to record security key-specific options, especially the flags
field.
with and ok markus@
OpenBSD-Commit-ID: 338a1f0e04904008836130bedb9ece4faafd4e49
We weren't following the rules re BN_CTX_start/BN_CTX_end and the places
we were using it didn't benefit from its use anyway. ok dtucker@
OpenBSD-Commit-ID: ea9ba6c0d2e6f6adfe00b309a8f41842fe12fc7a
signatures left on a shielded key, we need to transfer the number of
signatures left from the private to the public key. ok djm@
OpenBSD-Commit-ID: 8a5d0d260aeace47d372695fdae383ce9b962574
to delay the call to shield until we have received key specific options. -
when serializing xmss keys for shield we need to deal with all optional
components (e.g. state might not be loaded). ok djm@
OpenBSD-Commit-ID: cc2db82524b209468eb176d6b4d6b9486422f41f
including the new U2F signatures.
Don't use sshsk_ecdsa_sign() directly, instead make it reachable via
sshkey_sign() like all other signature operations. This means that
we need to add a provider argument to sshkey_sign(), so most of this
change is mechanically adding that.
Suggested by / ok markus@
OpenBSD-Commit-ID: d5193a03fcfa895085d91b2b83d984a9fde76c8c
functionality there (wrapping of base64-encoded data) to sshbuf functions;
feedback and ok markus@
OpenBSD-Commit-ID: 4dba6735d88c57232f6fccec8a08bdcfea44ac4c
private keys, enabled via "ssh-keygen -m PKCS8" on operations that save
private keys to disk.
The OpenSSH native key format remains the default, but PKCS8 is a
superior format to PEM if interoperability with non-OpenSSH software
is required, as it may use a less terrible KDF (IIRC PEM uses a single
round of MD5 as a KDF).
adapted from patch by Jakub Jelen via bz3013; ok markus
OpenBSD-Commit-ID: 027824e3bc0b1c243dc5188504526d73a55accb1
speculation and memory sidechannel attacks like Spectre, Meltdown, Rowhammer
and Rambleed. This change encrypts private keys when they are not in use with
a symmetic key that is derived from a relatively large "prekey" consisting of
random data (currently 16KB).
Attackers must recover the entire prekey with high accuracy before
they can attempt to decrypt the shielded private key, but the current
generation of attacks have bit error rates that, when applied
cumulatively to the entire prekey, make this unlikely.
Implementation-wise, keys are encrypted "shielded" when loaded and then
automatically and transparently unshielded when used for signatures or
when being saved/serialised.
Hopefully we can remove this in a few years time when computer
architecture has become less unsafe.
been in snaps for a bit already; thanks deraadt@
ok dtucker@ deraadt@
OpenBSD-Commit-ID: 19767213c312e46f94b303a512ef8e9218a39bd4
using the rsa-sha2-512 signature algorithm. Certificates signed by RSA keys
will therefore be incompatible with OpenSSH < 7.2 unless the default is
overridden.
Document the ability of the ssh-keygen -t flag to override the
signature algorithm when signing certificates, and the new default.
ok deraadt@
OpenBSD-Commit-ID: 400c9c15013978204c2cb80f294b03ae4cfc8b95
parsing rather than make the caller do it. Saves a lot of boilerplate code.
from markus@ ok djm@
OpenBSD-Commit-ID: 576bf784f9a240f5a1401f7005364e59aed3bce9
OpenSSL 1.1.0i has changed the behaviour of their PEM APIs,
so that empty passphrases are interpreted differently. This
probabalistically breaks loading some keys, because the PEM format
is terrible and doesn't include a proper MAC.
Avoid this by providing a basic callback to avoid passing empty
passphrases to OpenSSL in cases where one is required.
Based on patch from Jakub Jelen in bz#2913; ok dtucker@
is specified as "incorrect passphrase" instead of trying to choose between
that and "invalid format".
libcrypto can return ASN1 parsing errors rather than the expected
decrypt error in certain infrequent cases when trying to decrypt/parse
PEM private keys when supplied with an invalid passphrase.
Report and repro recipe from Thomas Deutschmann in bz#2901
ok markus@
OpenBSD-Commit-ID: b1d4cd92395f9743f81c0d23aab2524109580870
In ssh, when an agent fails to return a RSA-SHA2 signature when
requested and falls back to RSA-SHA1 instead, retry the signature to
ensure that the public key algorithm sent in the SSH_MSG_USERAUTH
matches the one in the signature itself.
In sshd, strictly enforce that the public key algorithm sent in the
SSH_MSG_USERAUTH message matches what appears in the signature.
Make the sshd_config PubkeyAcceptedKeyTypes and
HostbasedAcceptedKeyTypes options control accepted signature algorithms
(previously they selected supported key types). This allows these
options to ban RSA-SHA1 in favour of RSA-SHA2.
Add new signature algorithms "rsa-sha2-256-cert-v01@openssh.com" and
"rsa-sha2-512-cert-v01@openssh.com" to force use of RSA-SHA2 signatures
with certificate keys.
feedback and ok markus@
OpenBSD-Commit-ID: c6e9f6d45eed8962ad502d315d7eaef32c419dde
Remove all guards for calls to OpenSSL free functions -
all of these functions handle NULL, from at least OpenSSL 1.0.1g onwards.
Prompted by dtucker@ asking about guards for RSA_free(), when looking at
openssh-portable pr#84 on github.
ok deraadt@ dtucker@
OpenBSD-Commit-ID: 954f1c51b94297d0ae1f749271e184141e0cadae