RE: Filexfer version 3 vs. Filexfer version 4

[Richard Whalen <Whalenr%process.com@localhost>]

> -----Original Message-----
> From: Dan Davidson [mailto:dan.davidson%commatch.com@localhost]
> Sent: Monday, November 25, 2002 4:31 AM
> To: ietf-ssh%netbsd.org@localhost
> Subject: Filexfer version 3 vs. Filexfer version 4
> 
> 
> Hi,
> 
> 	The version 4 of the SSH File Transfer Protocol 
> strictly forbids the
> transmission
> of extensions in the SSH_FXP_INIT packet.
> However, it may happen that a version 3 Client initiating a connection
> towards a version 4 Server
> will send such extensions in the INIT message.
> 
> What behavior is expected from the Server in such a case ?
> 
> Thanks and best regards,
> Dan
> 
> 

I believe that this depends upon the server.  If the server "supports" V3 as
well as V4, then it should process the extension information.  If it only
supports V4, then it would be reasonable to ignore the entire message as it
is ill-formed and there is no error response to the SSH_FXP_INIT packet.

The extensions were removed from the SSH_FXP_INIT packet as their presence
can cause problems when a V3 client sends them to a V2 server.

----------------------
Richard Whalen
Process Software
508-879-6994x261