Subject: Re: ppp_mppe pkg vs /sys/net/if_ppp.c
To: Paul Dokas <firstname.lastname@example.org>
From: David Brownlee <email@example.com>
Date: 02/20/2001 13:09:24
It certainly sounds like NetBSD's ppp-comp.h should be changed to
handle Win2K pptp (whether or not it is violating any spec).
Could you submit a PR on this to make sure its not lost?
David/absolute -- www.netbsd.org: No hype required --
On Mon, 19 Feb 2001, Paul Dokas wrote:
> I've been struggling to get the poptop + ppp-mppe packages
> working correctly under -current so that a few Win2K laptops
> can use pptp to access behind a firewall. The problem that
> I've been having is whenever I attempt to connect to the NetBSD
> machine via pptp, I get endless streams of this:
> ppp/mppe: compress rejected: opt_len=32,o=12,o=6
> ppp/mppe: try increasing CCP_MAX_OPTION_LENGTH in ppp-comp.h
> I think that I've tracked down the reason.
> In the ppp-mppe package the LKM that gets built does not include
> if_ppp.c that is found in the package. Instead, it relies on
> the if_ppp.c that is found in /sys/net/if_ppp.c which includes
> the following lines:
> line 384:
> u_char ccp_option[CCP_MAX_OPTION_LENGTH];
> line 450-451:
> if (nb > sizeof(ccp_option))
> nb = sizeof(ccp_option);
> and /sys/net/ppp-comp.h has this #define:
> line 111-114:
> * Max # bytes for a CCP option
> #define CCP_MAX_OPTION_LENGTH 32
> However, in ppp-comp.h is found in the ppp-mppe package, this
> #define is:
> #define CCP_MAX_OPTION_LENGTH 64
> So, Win2k sends a CCP option of length > 32, NetBSD's if_ppp.c
> truncates it to 32 bytes and the rest ceases to function.
> I see two solutions:
> 1) change the #define of CCP_MAX_OPTION_LENGTH to 64 in
> 2) put the version of if_ppp.c found in the ppp-mppe pkg
> into the LKM that it builds.
> Speaking from a completely naive position WRT ppp and BSD networking,
> I'd prefer solution #1, however, the diffs between /sys/net/if_ppp.c
> and if_ppp.c in ppp-mppe are not simple to resolve. There's probably
> some code in the ppp-mppe version is might be required for MPPE to
> work properly.
> Paul Dokas firstname.lastname@example.org
> Don Juan Matus: "an enigma wrapped in mystery wrapped in a tortilla."