Skip site navigation (1)Skip section navigation (2)
Date:      Mon, 12 Aug 2002 13:57:26 +0430
From:      "soheil h" <soheil_h_y@hotmail.com>
To:        freebsd-net@freebsd.org
Subject:   TCP CHECKSUM ( emergency )
Message-ID:  <F102qsh1lBLMasiZAPG000146d4@hotmail.com>

next in thread | raw e-mail | index | archive | help


Hi list

as R. Stevens says in TCP/IP Ill. Vol.1 the tcp checksum is computed on the 
data and its own header.
but ip checksum is computed only on the ip header.
i want to know if the tcp checksum is computed on the ip header or not
and if i have a "struct mbuf m" that its m->m_data points to an ip packet 
and i know the tcp cksum is not true how can i compute the tcp cksum
the ip packet is passing through my FreeBSD gateway
something goes wrong on tcp checksums i want to compute it again .
some where in ip_input.c
if i know everything ,but this, is true.

(by the way ,using in_cksum() ,does this code work for me ? :
th->th_sum = in_cksum(m, m->m_len) )





_________________________________________________________________
Join the world’s largest e-mail service with MSN Hotmail. 
http://www.hotmail.com


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-net" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?F102qsh1lBLMasiZAPG000146d4>