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Date: Sun, 15 Mar 2009 11:02:06 +0100
From: Luigi Rizzo <rizzo@iet.unipi.it>
To: Sergey Matveychuk <sem@freebsd.org>
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Cc: freebsd-ipfw@freebsd.org, Dmitriy Demidov <dima_bsd@inbox.lv>
Subject: Re: keep-state rules inadequately handles big UDP packets
	or	fragmented IP packets?
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On Sun, Mar 15, 2009 at 12:38:37PM +0300, Sergey Matveychuk wrote:
> Dmitriy Demidov wrote:
> >Hi Luigi. Thank you for answer.
> >It is a big "surprise" for me that reassembling of IP datagrams is done 
> >not *before* they go into firewall, but *after* :(
> 
> But what's wrong with it? A fragment got from net, pass firewall and 
> store. After all fragments we got, OS reassembly a packet and pass it 
> through firewall again.

Currently we don't have a way to re-invoke the firewall after
reassembly. In fact, we should probably provide hooks before and
after reassembly, and use them in a configurable way.

cheers
luigi