Re: Interop lsh and SSH-2.0-GitLab-SSHD

[Mouse <mouse%Rodents-Montreal.ORG@localhost>]

> [...] gitlab's custom sshd [...] advertising itself as
> SSH-2.0-GitLab-SSHD when I connect to gitlab.com.

I notice it's also ignoring the required space after the
softwareversion (4253 4.2 - which admittedly contradicts itself, giving
syntax that requires a space but then giving an example without one and
calling it valid).

> When connecting to gitlab.com using lsh stopped working quite long
> ago, I assumed it was just because lsh was lagging support for
> current algorithms.

I wouldn't just assume that; I'd look at the algorithm lists offered by
the two ends...which I gather (from text I cut, below) you did.

It offers a fairly small list of algorithms, but (unlike github!) it at
least includes enough that it should interoperate with moussh - once I
tell my end to ignore the banner syntax error.  (I didn't go past the
"unrecognized host key, accept?" stage, because I have no presence
there.)  Here's what I see them offering:

855  ssh: peer's algorithms (%=unrecognized, *=disabled):
856           kex: %curve25519-sha256 %curve25519-sha256%libssh.org@localhost %ecdh-sha2-nistp256 %ecdh-sha2-nistp384 %ecdh-sha2-nistp521 diffie-hellman-group14-sha256 diffie-hellman-group14-sha1
857            hk: ssh-dss %ecdsa-sha2-nistp256 %ssh-ed25519 rsa-sha2-256 rsa-sha2-512 ssh-rsa
858      enc c->s: %aes128-gcm%openssh.com@localhost %chacha20-poly1305%openssh.com@localhost %aes256-gcm%openssh.com@localhost aes128-ctr aes192-ctr aes256-ctr
859      enc s->c: %aes128-gcm%openssh.com@localhost %chacha20-poly1305%openssh.com@localhost %aes256-gcm%openssh.com@localhost aes128-ctr aes192-ctr aes256-ctr
860      mac c->s: %hmac-sha2-256-etm%openssh.com@localhost %hmac-sha2-512-etm%openssh.com@localhost %hmac-sha2-256 %hmac-sha2-512 hmac-sha1
861      mac s->c: %hmac-sha2-256-etm%openssh.com@localhost %hmac-sha2-512-etm%openssh.com@localhost %hmac-sha2-256 %hmac-sha2-512 hmac-sha1
862     comp c->s: none
863     comp s->c: none

> [...]
> But authenticating in the same way to gitlab.com still fails.  The
> curious thing is that the server appears to just close the
> connection, I don't get any SSH_MSG_USERAUTH_FAILURE, not even a
> SSH_MSG_DISCONNECT.

Curious.  No, I have no idea what's behind that.  I'd be interested to
hear if you ever do learn what's behind it.

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