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From: Andrew Beverley <andy@andybev.com>
To: "Ethy H. Brito" <ethy.brito@inexo.com.br>
Cc: netfilter@vger.kernel.org
Subject: Re: filter before NAT
Date: Tue, 11 Oct 2011 20:37:52 +0100	[thread overview]
Message-ID: <1318361872.26402.2504.camel@andybev-desktop> (raw)
In-Reply-To: <20111011112453.49d1a3f1@pulsar.inexo.com.br>

On Tue, 2011-10-11 at 11:24 -0300, Ethy H. Brito wrote:
> Hi All.
> 
> I am trying to control some outbound traffic thru a Linux NATing box via this:
> 
> $TC filter add dev $INTERNET protocol ip parent 3: pref 1 \
>    u32  \
>       match ip src 192.168.106.2  \
>    flowid 3:5602
> 
> The problem is that the packets are hooked *after* passing SNAT and all the
> rules can see is the outbound IP. So no redirects to the corresponding
> flowid occur.
> 
> Is it possible to make the filter rule above "see" the packets before they
> get NATed?
> 

How about marking them using an iptables rule before SNAT? The mangle
table of POSTROUTING sits before the nat table.

Andy



  reply	other threads:[~2011-10-11 19:37 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-10-11 14:24 filter before NAT Ethy H. Brito
2011-10-11 19:37 ` Andrew Beverley [this message]
2011-10-11 19:52   ` Ethy H. Brito
2011-10-12  7:01     ` Nikolay Kichukov

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