Subject: Re: [scp][recive] packet_type 100 but awaits 99

Re: [scp][recive] packet_type 100 but awaits 99

From: Daniel Stenberg <>
Date: Thu, 13 Jun 2013 00:09:42 +0200 (CEST)

On Wed, 12 Jun 2013, Belau, Rene (ext) wrote:

> I recive a wrong packet_type (packet_type 100, awaits 99) from ssh-demon on
> the server-side, so libssh2 returns a channel eof and closes/frees the
> channel without file transport.

Clearly, but I can't spot what libssh2 makes wrong.

> Putty can handle the packet_type 100. Putty resends the request
> channel_request multiply times with a packet of packet_type 2 between.

But why is that correct? 100 means SSH_MSG_CHANNEL_FAILURE, why is sending
SSH_MSG_IGNORE a fine reaction to that?

If that is truly what putty does, then I can only assume it is a sort of
work-around for a silly server. A work-around that libssh2 doesn't perform...

Have you checked the putty source code to see what heuristics they might have
to decide when to send a 2 and when to just accept the failure?

Received on 2013-06-13