Matthias Scheler wrote:

>>    - adding homebrewed mss clamping code into if_pppoe.c
> 
> Could you perhaps add this code to IPF? That is the place where it really
> belongs.

Actually, I was thinking it belongs in ip_output.c, with a switch 
(-proto3?) that could be set per route to cap the TCP MSS at the MTU for 
that route (or interface if there is no MTU for the route) for sessions 
initiated external to the NetBSD box.  This more closely parallels how 
the TCP stack on the NetBSD box chooses it's own MSS values.

I have some local changes that partially implement this, but I haven't 
finished them yet.

Does this seem like a reasonable implementation?

Mike.