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

[Darren Tucker]

On Thu, Apr 9, 2015 at 1:07 PM, Bryan Drewery <bryan at shatow.net> wrote:

> On 4/8/2015 9:56 PM, Darren Tucker wrote:ading 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
>

Those are channel requests not global requests.  sshd does this in
serverloop.c:

         if ((channel_id = channel_find_open()) == -1) {
                packet_start(SSH2_MSG_GLOBAL_REQUEST);
                packet_put_cstring("keepalive at openssh.com");
                packet_put_char(1);     /* boolean: want reply */
        } else {
                channel_request_start(channel_id, "keepalive at openssh.com",
1);
        }

and Tera Term seems to handle the channel requests just fine.  Presumably
if you could get a connection with no active channels (ie the equivalent of
ssh -N) then perhaps it'd have a problem, or perhaps that's not even
possible with that client.

-- 
Darren Tucker (dtucker at zip.com.au)
GPG key 8FF4FA69 / D9A3 86E9 7EEE AF4B B2D4  37C9 C982 80C7 8FF4 FA69
    Good judgement comes with experience. Unfortunately, the experience
usually comes from bad judgement.