From mboxrd@z Thu Jan  1 00:00:00 1970
From: Emmanuel Guiton <emmanuel@netlab.hut.fi>
Subject: Re: change ip address in the hook
Date: Tue, 30 Mar 2004 08:13:53 +0300
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Hi!

Can you be a bit more precise in what you do when you "change the ip 
address of a packet in the LOCAL_OUT hook and let it send out"? What are 
all the operations you do? Which address (source / destination) do you 
change? Do you calculate a new IP checksum after having changed the IP 
address?

       Emmanuel


lmn@mail.xprtsol.com wrote:

>Hi,
>
>For example, I want to change the ip address of a packet in the LOCAL_OUT hook and let it send out, but I didn't see the packet on the wire. (Route for the modified ip addresses existed.) Similar things happen for the PRE_ROUTING hook. This is like doing the NAT manually.
>
>If I use iptables command to add a rule doing the similar function, I can see the packet was sent out. So what is the difference inside these two approaches?
>
>Thanks,
>
>LMN
>
>  
>