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To: Archie Cobbs <archie@whistle.com>
Cc: hackers@freebsd.org
Subject: Re: ipdivert & masqd 
In-Reply-To: Your message of "Mon, 20 Jan 1997 13:29:18 PST."
             <199701202129.NAA12394@bubba.whistle.com> 
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Date: Tue, 21 Jan 1997 23:21:21 +0000
From: Brian Somers <brian@awfulhak.demon.co.uk>
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> 
> > Well, as a start to "masqd", I've written a filter that doesn nothing.  It
> > receives a packet, outputs bits of info, then inserts it back into the IP
> > stream (after fixing the IP checksum if it's an "in" packet).
> > 
> > Works fine for tcp connections (telnet at least) & udp (NFS at least), but
> > only half-works for ICMP.  It gets the incoming ICMP (ping), fixes the sum
> > and does the sendto(), but never sees the reply.  The reply is received by
> > the sender though.....
> 
> What do your ipfw rules look like while masqd is running?
> 
> -Archie

Not that interesting...
The machines in question are 10.0.1.3 and 10.0.1.254.  The 254 machine is
doing the 'divert's.

/sbin/ipfw -f flush
/sbin/ipfw add 100 divert 6668 all from 10.0.1.3 to 10.0.1.254
/sbin/ipfw add 100 divert 6668 all from 10.0.1.254 to 10.0.1.3
/sbin/ipfw add 65000 pass all from any to any

-- 
Brian <brian@awfulhak.demon.co.uk>, <brian@freebsd.org>
      <http://www.awfulhak.demon.co.uk/>
Don't _EVER_ lose your sense of humour....