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From: Guillaume Morin <guillaume@morinfr.org>
To: "Shipman, Jeffrey E" <jeshipm@sandia.gov>
Cc: "'linux-kernel@vger.kernel.org'" <linux-kernel@vger.kernel.org>
Subject: Re: TCP checksum?
Date: Thu, 13 Jun 2002 17:28:51 +0200	[thread overview]
Message-ID: <20020613152851.GA3442@morinfr.org> (raw)
In-Reply-To: <03781128C7B74B4DBC27C55859C9D73809840636@es06snlnt>

Dans un message du 13 jun à  9:10, Shipman, Jeffrey E écrivait :
>
> I'm looking for a function similar to skb_checksum(), but
> for the tcphdr->check field. I'm playing around with a module
> I've written for netfilter and I would like to modify options of
> the IP and TCP headers. For example, right now I'm trying
> to set the destination IP to the source IP, but the TCP checksum
> is coming out incorrectly. How can I calculate this checksum?

There is a netfilter function for that. Look at
ip_nat_core.c:ip_nat_cheat_check.

-- 
Guillaume Morin <guillaume@morinfr.org>

          5 years from now everyone will be running free GNU on their
           200 MIPS, 64M SPARCstation-5 (Andy Tanenbaum, 30 Jan 1992)

  reply	other threads:[~2002-06-13 15:28 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2002-06-13 15:10 TCP checksum? Shipman, Jeffrey E
2002-06-13 15:28 ` Guillaume Morin [this message]
2002-06-13 15:34 ` Padraig Brady
2002-06-14  3:51 ` Fabrice MARIE
  -- strict thread matches above, loose matches on Subject: below --
2002-06-13 19:58 Shipman, Jeffrey E

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