From owner-freebsd-net@FreeBSD.ORG  Thu Aug 23 06:34:37 2007
Return-Path: <owner-freebsd-net@FreeBSD.ORG>
Delivered-To: freebsd-net@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id 5D02A16A418
	for <freebsd-net@freebsd.org>; Thu, 23 Aug 2007 06:34:37 +0000 (UTC)
	(envelope-from jinmei@isl.rdc.toshiba.co.jp)
Received: from shuttle.wide.toshiba.co.jp (shuttle.wide.toshiba.co.jp
	[IPv6:2001:200:1b1::35])
	by mx1.freebsd.org (Postfix) with ESMTP id 20F4813C458
	for <freebsd-net@freebsd.org>; Thu, 23 Aug 2007 06:34:37 +0000 (UTC)
	(envelope-from jinmei@isl.rdc.toshiba.co.jp)
Received: from jmb.local (unknown [IPv6:2001:200:1b1:1010:217:f2ff:fe26:34a0])
	by shuttle.wide.toshiba.co.jp (Postfix) with ESMTP id BDA5473019;
	Thu, 23 Aug 2007 15:34:34 +0900 (JST)
Date: Thu, 23 Aug 2007 15:34:25 +0900
Message-ID: <m1bqcywyha.wl%jinmei@isl.rdc.toshiba.co.jp>
From: JINMEI Tatuya / =?ISO-2022-JP?B?GyRCP0BMQEMjOkgbKEI=?=
	<jinmei@isl.rdc.toshiba.co.jp>
To: Daniel Hartmeier <daniel@benzedrine.cx>
In-Reply-To: <20070821163505.GA28667@insomnia.benzedrine.cx>
References: <200708211010.l7LAA6V7082258@freefall.freebsd.org>
	<20070821121118.GF27160@insomnia.benzedrine.cx>
	<1187703472.22531.4.camel@localhost.localdomain>
	<20070821135048.GA32421@insomnia.benzedrine.cx>
	<1187705811.30269.5.camel@localhost.localdomain>
	<20070821143125.GB32421@insomnia.benzedrine.cx>
	<1187707117.846.3.camel@localhost.localdomain>
	<20070821145047.GC32421@insomnia.benzedrine.cx>
	<1187713068.3973.6.camel@localhost.localdomain>
	<20070821163505.GA28667@insomnia.benzedrine.cx>
User-Agent: Wanderlust/2.14.0 (Africa) Emacs/22.0 Mule/5.0 (SAKAKI)
MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka")
Content-Type: text/plain; charset=US-ASCII
Cc: freebsd-net@freebsd.org, Jacek Zapala <jacek@ipv6.jacek.it.pl>
Subject: Re: kern/115413: [ipv6] ipv6 pmtu not working
X-BeenThere: freebsd-net@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Networking and TCP/IP with FreeBSD <freebsd-net.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-net>,
	<mailto:freebsd-net-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-net>
List-Post: <mailto:freebsd-net@freebsd.org>
List-Help: <mailto:freebsd-net-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-net>,
	<mailto:freebsd-net-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Thu, 23 Aug 2007 06:34:37 -0000

At Tue, 21 Aug 2007 18:35:05 +0200,
Daniel Hartmeier <daniel@benzedrine.cx> wrote:

> > But I'm not sure if I understood well - you suspect that only 8 bytes of
> > tcp header are copied from the original tcp packet to the icmp message
> > by the router?
> 
> No, the router is only required (by the RFCs) to quote the first 8 bytes
> of the TCP header.

This is not true for IPv6.  From Section 2.4 of RFC4443:

   (c) Every ICMPv6 error message (type < 128) MUST include as much of
       the IPv6 offending (invoking) packet (the packet that caused the
       error) as possible without making the error message packet exceed
       the minimum IPv6 MTU [IPv6].

					JINMEI, Tatuya
					Communication Platform Lab.
					Corporate R&D Center, Toshiba Corp.
					jinmei@isl.rdc.toshiba.co.jp