[2182] in linux-net channel archive
Re: LCP echo problems (again)
daemon@ATHENA.MIT.EDU (Paul Mackerras)
Wed Mar 20 18:31:06 1996
Date: Thu, 21 Mar 1996 09:47:38 +1100
From: Paul Mackerras <paulus@cs.anu.edu.au>
To: longyear@netcom.com
CC: linuxsys@ssg.com, linux-net@vger.rutgers.edu
In-reply-to: <199603201507.HAA00312@costello.longyear.com>
Al Longyear wrote:
> Linux pppd version 2.2 sends an empty CCP frame if you don't have any
> compressors defined.
If no compressors are enabled, pppd is supposed to bring up CCP in
"silent" mode, so it won't send a CCP frame unless it sees one from
the peer. It needs to be able to send an empty CCP frame in the case
that the peer wants us to compress stuff going to it, and we're
willing, but we don't want stuff coming to us compressed.
It looks to me like the problem is that pppd is not checking with the
kernel which compression options are supported before making the
decision about whether to open CCP in silent mode or not. This is a
bug which can be fixed by changing the line in ccp_open which says
if (!ANY_COMPRESS(ccp_wantoptions[unit]))
to
ccp_resetci(f);
if (!ANY_COMPRESS(ccp_gotoptions[unit]))
Also, I think we need a -ccp option (or something) to disable CCP
completely.
Paul.
