From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Josh Berry" <josh.berry@linknet-solutions.com>
Subject: Re: Modify packets using netfilter
Date: Sun, 14 Dec 2003 19:14:02 -0600 (CST)
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To: "Jee J.Z." <jz105@york.ac.uk>
Cc: netfilter@lists.netfilter.org

Snort-Inline is able to do this: http://snort-inline.sourceforge.net.  You
can have it modify (it calls it replacing) packets.  The main caveat to
this is that you have to replace data with the same amount of data
example:

Replacing the string "hacker" with "hack" would not work.

> Hi Antony and all,
>
> Thanks for your reply. What I am trying to do is to get the whole packets
> including their payloads and store them into a self defined queue, and
> randomly modify some bits in each packet. I am using iptables userspace
> programming. Does anybody have some good idea how to achieve this? Thank
> you.
>
> Regards,
> Jee


Thanks,
Josh Berry, CTO
LinkNet-Solutions
469-831-8543
josh.berry@linknet-solutions.com