From owner-freebsd-net@FreeBSD.ORG Wed Feb 27 11:47:48 2008 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 D2F46106567B for ; Wed, 27 Feb 2008 11:47:48 +0000 (UTC) (envelope-from stefan.lambrev@moneybookers.com) Received: from blah.sun-fish.com (blah.sun-fish.com [217.18.249.150]) by mx1.freebsd.org (Postfix) with ESMTP id 93CC98FC25 for ; Wed, 27 Feb 2008 11:47:48 +0000 (UTC) (envelope-from stefan.lambrev@moneybookers.com) Received: by blah.sun-fish.com (Postfix, from userid 1002) id BD6041B10EF9; Wed, 27 Feb 2008 12:47:46 +0100 (CET) X-Spam-Checker-Version: SpamAssassin 3.2.3 (2007-08-08) on blah.cmotd.com X-Spam-Level: X-Spam-Status: No, score=-10.6 required=5.0 tests=ALL_TRUSTED,BAYES_00 autolearn=ham version=3.2.3 Received: from hater.haters.org (hater.cmotd.com [192.168.3.125]) by blah.sun-fish.com (Postfix) with ESMTP id B26671B10ED2; Wed, 27 Feb 2008 12:47:42 +0100 (CET) Message-ID: <47C54DDE.8070605@moneybookers.com> Date: Wed, 27 Feb 2008 13:47:42 +0200 From: Stefan Lambrev User-Agent: Thunderbird 2.0.0.9 (X11/20080212) MIME-Version: 1.0 To: d@delphij.net References: <47B2488D.70707@delphij.net> <47B34ED4.6090302@delphij.net> In-Reply-To: <47B34ED4.6090302@delphij.net> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable Cc: =?UTF-8?B?SklOTUVJIFRhdHV5YSAvIOelnuaYjumBlOWTiQ==?= , ume@FreeBSD.org, freebsd-net@freebsd.org Subject: Re: [RESOLVED] Re: Strange resolver behavior 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: Wed, 27 Feb 2008 11:47:48 -0000 Greetings, Xin LI wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > JINMEI Tatuya / =E7=A5=9E=E6=98=8E=E9=81=94=E5=93=89 wrote: > [snip] > > At the beginning I was confused with host(1) and resolver library, they= > are different problems, sorry for the confusion. > > I think Hajimu-san's analysis was correct that it was caused by the > check in resolver, here is a ktrace output from a system without patche= d > libc: > > http://www.delphij.net/kdump.txt > > Note that, with a patched (with ume@'s patch) resolver, the program > *does* worked as expected, also this will make firefox to be able to > resolve the domain name. > > Test program can be downloaded from http://www.delphij.net/test.c . > With patched libc you will get no output (expected), and with unpatched= > libc you will get "Unknown server error" and will be unable to get the = A RR. > > It turns out that the baidu.com DNS administrator might be unaware of > the potential violation of RFC 952 "ASSUMPTIONS" and RFC 1034 Section > 3.5. However, I am afraid that there are some DNS server > implementations that does allow '_'s in domain names, so if there is no= > potential risks allowing it from the resolver side I think it might be = a > good idea to be more permissive for this case, because there are real > uses of it, and other operating systems does allow it at the client sid= e. > =20 Did you check http://tools.ietf.org/html/rfc2782 ? It is "PROPOSED STANDARD" and MS DNS in Win2003 already uses it (if you=20 have domain controller for example). --=20 Best Wishes, Stefan Lambrev ICQ# 24134177