From mboxrd@z Thu Jan  1 00:00:00 1970
From: Patrick Schaaf <bof@bof.de>
Subject: Re: detection of the third tcp packet in a tcp connection setup
Date: Thu, 27 Jun 2002 20:53:19 +0200
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To: Ramin Alidousti <ramin@cannon.eng.us.uu.net>
Cc: netfilter@lists.samba.org

Hi Ramin,

> Does anyone have a good solution to catch the third (ACK) packet
> in a tcp connection setup?

Maybe you could use the CONNMARK patch, found in patch-o-matic?
Mark the conntrack one way for the first packet of a new connection,
and later match on that mark, changing it to something else when that
match hits.

Thanks for a nice idea from the "how do I bend iptables into a
programming language" department. :-)

best regards
  Patrick