From mboxrd@z Thu Jan  1 00:00:00 1970
From: Francis GASCHET <fg@numlog.fr>
Subject: Re: Filtering PPP traffic
Date: Fri, 18 Apr 2003 17:25:03 +0200
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To: SBlaze <dagent.geo@yahoo.com>
Cc: netfilter@lists.netfilter.org


Hello,

The bridge we use is the kernel patch provided by 
http://bridge.sourceforge.net
On the card side, we use Ethernet over ATM bridging (RFC 1483/2684 
kernel module). It emulates an "Ethernet like" device : nas0.
The pppOE daemon sits in the VM where it reads and writes ppp frames on 
a virtual eth device created with TAP (http://Vtun.sourceforge.net).
The official address is carried by this virtual eth device.
The bridge forwards pppOE packets between the nas0 and the tap0 devices.
The goal is to use a bridged firewall. That means : a FireWall which is 
not visible from the external network.

The problem is to be able to filter the pppOE packets that flow across 
the bridge.

-- 
Francis GASCHET / NUMLOG
http://www.numlog.fr
Tel.: +33 (0) 130 791 616
Fax.: +33 (0) 130 819 286




Thanks for any help.

SBlaze wrote:

>You should be able to filter at the "eth0" level of your diagram...
>
>I kinda need more information on your "BRIDGE" before I could suggest something
>else.. If by bridge you mean it bridges the DSL modem and the LAN...then your
>eth0 is in the same machine you are calling a bridge?
>
>In that case you should theoretically filter the eth0 device
>
>
>--- Francis GASCHET <fg@numlog.fr> wrote:
>  
>
>>Hi list,
>>
>>Is there somebody who knows a possibility to apply netfilter rules to 
>>ppp packets ?
>>
>>Configuration :
>>
>>DSL - PCI modem card - BRIDGE - eth0 (in a virtual machine)
>>
>>I would like to filter the traffic which flows across the bridge, but at 
>>this level, the IP traffic is encapsulated...
>>
>>Any clue ?
>>
>>Ciao.
>>
>>    
>>