From owner-freebsd-net@FreeBSD.ORG Sat Jul 28 22:50:52 2012 Return-Path: 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 6C1C6106564A; Sat, 28 Jul 2012 22:50:52 +0000 (UTC) (envelope-from bz@FreeBSD.org) Received: from mx1.sbone.de (bird.sbone.de [46.4.1.90]) by mx1.freebsd.org (Postfix) with ESMTP id E5AFA8FC14; Sat, 28 Jul 2012 22:50:51 +0000 (UTC) Received: from mail.sbone.de (mail.sbone.de [IPv6:fde9:577b:c1a9:31::2013:587]) (using TLSv1 with cipher ADH-CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by mx1.sbone.de (Postfix) with ESMTPS id EEC7925D387B; Sat, 28 Jul 2012 22:50:50 +0000 (UTC) Received: from content-filter.sbone.de (content-filter.sbone.de [IPv6:fde9:577b:c1a9:31::2013:2742]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.sbone.de (Postfix) with ESMTPS id 1CA21BE8553; Sat, 28 Jul 2012 22:50:50 +0000 (UTC) X-Virus-Scanned: amavisd-new at sbone.de Received: from mail.sbone.de ([IPv6:fde9:577b:c1a9:31::2013:587]) by content-filter.sbone.de (content-filter.sbone.de [fde9:577b:c1a9:31::2013:2742]) (amavisd-new, port 10024) with ESMTP id ElrPKQDRKf7h; Sat, 28 Jul 2012 22:50:48 +0000 (UTC) Received: from nv.sbone.de (nv.sbone.de [IPv6:fde9:577b:c1a9:31::2013:138]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.sbone.de (Postfix) with ESMTPSA id 6EFA9BE8552; Sat, 28 Jul 2012 22:50:48 +0000 (UTC) Date: Sat, 28 Jul 2012 22:50:47 +0000 (UTC) From: "Bjoern A. Zeeb" To: Doug Barton In-Reply-To: <50117FB2.1060306@FreeBSD.org> Message-ID: References: <50117DB0.7010909@mh-sec.de> <50117FB2.1060306@FreeBSD.org> X-OpenPGP-Key-Id: 0x14003F198FEFA3E77207EE8D2B58B8F83CCF1842 MIME-Version: 1.0 Content-Type: MULTIPART/MIXED; BOUNDARY="0-1307323017-1343515848=:4474" Cc: freebsd-net@FreeBSD.org Subject: Re: Fwd: Re: [ipv6hackers] funny FreeBSD bug X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 28 Jul 2012 22:50:52 -0000 This message is in MIME format. The first part should be readable text, while the remaining parts are likely unreadable without MIME-aware tools. --0-1307323017-1343515848=:4474 Content-Type: TEXT/PLAIN; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8BIT On Thu, 26 Jul 2012, Doug Barton wrote: > FYI, this conversation is happening in the list below. I have no opinion > regarding whether it is a bug or not, but I thought folks here might be > interested. > You can point the people at both the RFC and the SA we have issues a couple of years ago and why it's always 4 or 8 bytes below the minimal MTU. It's all good. > > > -------- Original Message -------- > Subject: Re: [ipv6hackers] funny FreeBSD bug > Date: Thu, 26 Jul 2012 19:26:08 +0200 > From: Marc Heuse > Reply-To: IPv6 Hackers Mailing List > To: IPv6 Hackers Mailing List , > Simon Perreault > > Hi Simon, > > Am 26.07.2012 17:47, schrieb Simon Perreault: >> Le 2012-07-26 08:35, Marc Heuse a écrit : >>> I found a funny bug in freebsd (9.0 with all updates): >>> if you send an ICMP toobig message to it with a too low MTU size, >>> FreeBSD will prepend any packet data with an one-shot fragment (or >>> atomic fragment as Fernando calls it). >> >> Why do you think it's a bug? > > first it servs no use to add the fragmentation header if the packet is > not fragmented. second I have not seen this behaviour in other OS, > however I havent looked for it though. > >> Seems like normal IPv6 behaviour to me. It's in the RFC... > I cant remember having seen this in any rfc - do you have a pointer? > > Greets, > Marc > > -- > Marc Heuse > www.mh-sec.de > > PGP: FEDD 5B50 C087 F8DF 5CB9 876F 7FDD E533 BF4F 891A > _______________________________________________ > Ipv6hackers mailing list > Ipv6hackers@lists.si6networks.com > http://lists.si6networks.com/listinfo/ipv6hackers > > > _______________________________________________ > freebsd-net@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-net > To unsubscribe, send any mail to "freebsd-net-unsubscribe@freebsd.org" > -- Bjoern A. Zeeb You have to have visions! Stop bit received. Insert coin for new address family. --0-1307323017-1343515848=:4474--