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From: Kristian Evensen <kristian.evensen@gmail.com>
To: aragonx@dcsnow.com
Cc: netfilter@vger.kernel.org
Subject: Re: Identifiying and modifying packets
Date: Thu, 26 Mar 2009 20:23:32 +0100	[thread overview]
Message-ID: <49CBD634.4000203@gmail.com> (raw)
In-Reply-To: <e4bd24ae0b0148637ca48bf14e29b27a.squirrel@www.dcsnow.com>

Hi,
> Can someone tell me what tools I could use to examine outbound packet data
> for the usernames and modify it if it matches a list of accounts we want
> to block?
>
>   
I suggest writing your own netfilter-module that does the packet 
inspection, and if a packet matches you can simply return NF_DROP to 
instruct the kernel to drop the packet. A good tutorial/book is 
available here: http://jengelh.medozas.de/

Maybe you can do something similar with libpcap, but I am not sure if 
you can drop packets.

-Kristian

  reply	other threads:[~2009-03-26 19:23 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-03-26 18:24 Identifiying and modifying packets aragonx
2009-03-26 19:23 ` Kristian Evensen [this message]
2009-03-26 19:43   ` aragonx
2009-03-26 20:45     ` Kristian Evensen
2009-03-26 20:54       ` Verify rules Scott Miller
2009-03-26 23:35         ` Mike Wright
2009-03-27  8:05         ` Mart Frauenlob
2009-03-27 17:15           ` Scott Miller
2009-03-27 18:49             ` Mike Wright
2009-03-27 18:58               ` Mike Wright
2009-03-27 19:49                 ` Scott Miller
2009-03-27 19:55                   ` Mike Wright
2009-03-27 20:12                     ` Scott Miller
2009-03-27 22:49                       ` Mart Frauenlob
2009-03-27 19:56                   ` Mike Wright
2009-03-27 19:25               ` Rob Sterenborg

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