Hi,
OpenSSH 8.2 (https://www.openssh.com/txt/release-8.2) supports "ecdsa-sk" and
"ed25519-sk” key types to support U2F/FIDO security keys and I was wondering if
libssh could support them, too?
For supporting them server-side, I think you'd just need to implement the
additional key types
sk-ecdsa-sha2-nistp...@openssh.com
sk-ecdsa-sha2-nistp256-cert-...@openssh.com
sk-ssh-ed25...@openssh.com
sk-ssh-ed25519-cert-...@openssh.com
…and parse their signature a bit differently from the normal ecdsa and ed25519
signatures. E.g. they include an additional “counter" and “user present” value.
Details on the format are here:
https://github.com/openssh/openssh-portable/blob/master/PROTOCOL.u2f
Let me know what you think.
