Tera Term, Unexpected SSH2 message(80) on current stage(6) [was Re: SAP-2015-3-1 issues]

[Bryan Drewery]

On 4/8/2015 9:56 PM, Darren Tucker wrote:
> On Thu, Apr 9, 2015 at 12:28 PM, Bryan Drewery <bryan at shatow.net
> <mailto:bryan at shatow.net>> wrote:
> 
>     It seems that Tera Term has fixed this but not yet released a build
>     with it.
> 
>     http://en.sourceforge.jp/ticket/browse.php?group_id=1412&tid=35010
>     http://en.sourceforge.jp/projects/ttssh2/scm/svn/commits/5829
> 
> 
> Reading that change it looks like Tera Term before that change would
> also crash when ClientAliveInterval is enabled on the server?

I see what you're saying but I am unable to create any error by enabling
ClientAliveInterval. I set it to 1 and get no errors on the client. sshd
debugging:

debug2: channel 0: request keepalive at openssh.com confirm 1
debug2: tcpwinsz: 65700 for connection: 3
debug2: tcpwinsz: 65700 for connection: 3
debug1: Got 100/16 for keepalive
debug2: tcpwinsz: 65700 for connection: 3
debug2: channel 0: request keepalive at openssh.com confirm 1
debug2: tcpwinsz: 65700 for connection: 3
debug2: tcpwinsz: 65700 for connection: 3
debug1: Got 100/17 for keepalive
debug2: tcpwinsz: 65700 for connection: 3
debug2: channel 0: request keepalive at openssh.com confirm 1
debug2: tcpwinsz: 65700 for connection: 3
debug2: tcpwinsz: 65700 for connection: 3
debug1: Got 100/18 for keepalive
debug2: tcpwinsz: 65700 for connection: 3
debug2: channel 0: request keepalive at openssh.com confirm 1
debug2: tcpwinsz: 65700 for connection: 3
debug2: tcpwinsz: 65700 for connection: 3
debug1: Got 100/19 for keepalive
debug2: tcpwinsz: 65700 for connection: 3

I think it just ignores the SSH2_MSG_GLOBAL_REQUEST packets once it is
fully connected. Seeing them before the full connection is unexpected to
it as the error seems to imply (Unexpected... on current stage). I don't
see anything in ssh.c handling keepalive messages.

> 
>     This patch fixes it in OpenSSH for me:
>     https://people.freebsd.org/~bdrewery/patches/ttssh-host-keys.diff
> 
>