From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Leblond <eric@regit.org>
Subject: Re: Modify packets using netfilter
Date: Sat, 13 Dec 2003 21:21:25 +0100
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To: "Jee J.Z." <jz105@york.ac.uk>
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Le sam 13/12/2003 =C3=A0 17:45, Jee J.Z. a =C3=A9crit :
> Hi Antony and all,
>=20
> 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 ran=
domly modify some bits in each packet.=20
> I am using iptables userspace programming. Does anybody have some good id=
ea how to achieve this? Thank you.

with libipq you can modify the payload of the packet :

Take from man page :
int ipq_set_verdict(const struct ipq_handle *h, ipq_id_t  id,  unsigned
       int verdict, size_t data_len, unsigned char *buf);

if data_len is not 0 and buf is not NULL, the header and payload of the
packet get replaced by the datas pointed by buf.

BR,
--=20
Eric Leblond
Nufw, Now User Filtering Works (http://www.nufw.org)

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