Client fails kex after c38ea634893a1975dbbec798fb968c9488013f4a

[Darren Tucker]

On Fri, Jan 20, 2017 at 2:49 AM, Neale Ferguson <neale at sinenomine.net> wrote:
> I have a Putty variant that works well with openSSH up until 7.4. After
> git bisecting I found that after the application of
> c38ea634893a1975dbbec798fb968c9488013f4a the client fails with host key
> mismatch. The commit in question appears to remove vestiges of ssh-1
> support but my client is using 2.0. I am trying to work out what in that
> commit would lead to the symptoms. I have been through the patch and it
> appears to be remove the ssh-1 option processing (-b etc.) but nothing
> directly relating to key exchange processing.
>
> I have verified that if I reverse the patch the client works and when I
> put it back on it fails.
>
> I assume it is a flow-on affect of something but I am struggling to
> connect the dots. Any suggestions of what to look at?

Could you post the server-side debug logs (sshd -ddd) from before and
after the suspect commit?  Comparing them would give some indication
of what's different.

-- 
Darren Tucker (dtucker at zip.com.au)
GPG key 11EAA6FA / A86E 3E07 5B19 5880 E860  37F4 9357 ECEF 11EA A6FA (new)
    Good judgement comes with experience. Unfortunately, the experience
usually comes from bad judgement.