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From: Paolo Pisati <p.pisati@oltrelinux.com>
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To: Luigi Rizzo <rizzo@iet.unipi.it>
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Cc: freebsd-ipfw@FreeBSD.org, Dmitriy Demidov <dima_bsd@inbox.lv>,
	Alex Dupre <ale@FreeBSD.org>
Subject: Re: keep-state rules inadequately handles big UDP packets
 or	fragmented IP packets?
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Luigi Rizzo wrote:
>
> Thinking more about it, i believe that calling reass as an explicit
> firewall action is useless, because if ip_reass fails due to lack of
> all fragments you are back to square one:
> 	what do I do with this fragment ?
>   

AFAIK ip_reass() never fails: if it's the last fragment it reassembles 
the packet and return it, else it queues the fragment for later
reassembly.
and i guess we must extend ip fragment detection together with the reass 
action  because 'frag' matches only  packet with  a non-zero offset
(aka not the first fragment).

bye,
P.