From owner-freebsd-current@FreeBSD.ORG Fri Nov 23 10:52:11 2007 Return-Path: Delivered-To: current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id AA96416A421 for ; Fri, 23 Nov 2007 10:52:11 +0000 (UTC) (envelope-from ianf@clue.co.za) Received: from munchkin.clue.co.za (munchkin.clue.co.za [66.219.59.160]) by mx1.freebsd.org (Postfix) with ESMTP id 62E2C13C4EB for ; Fri, 23 Nov 2007 10:52:11 +0000 (UTC) (envelope-from ianf@clue.co.za) DomainKey-Signature: a=rsa-sha1; q=dns; c=simple; s=20070313; d=clue.co.za; h=Received:Received:Received:To:cc:From:Subject:In-Reply-To:X-Attribution:Date:Message-Id; b=yWtiaAX7gvFQPAAAYjE6wmiBe32tgE0KaO6kyuv4zKKjWA9+20UgFdDPSxWvawGPlm+c5RYmZ05OSrtuZHeiMwegwX35rvHlA2V/KK1Th3mHJFoOwEWO5CiWpyYp7TQXDmi3L/FeAwj8ZtQaVuuxeJa9qDVeV7vXnwn9amh6SgrPWUg+wVLIPQcdXXdr95dg8U5Ne6jIaeFAnV7YIrtAxRPBArt1RcA5fsMibPYgEcbxUkdpDwIPgYDzgLOjIwtK; Received: from uucp by munchkin.clue.co.za with local-rmail (Exim 4.67) (envelope-from ) id 1IvW8m-0003QY-CK; Fri, 23 Nov 2007 10:52:08 +0000 Received: from ianf.clue.co.za ([10.0.0.6] helo=clue.co.za) by urchin.clue.co.za with esmtpsa (TLSv1:AES256-SHA:256) (Exim 4.67) (envelope-from ) id 1IvW8Q-00046d-4I; Fri, 23 Nov 2007 10:51:46 +0000 Received: from localhost ([127.0.0.1] helo=clue.co.za) by clue.co.za with esmtp (Exim 4.68 (FreeBSD)) (envelope-from ) id 1IvW8P-0000Kl-0v; Fri, 23 Nov 2007 12:51:45 +0200 To: "Kip Macy" From: Ian FREISLICH In-Reply-To: Message from "Kip Macy" of "Fri, 23 Nov 2007 00:51:50 PST." X-Attribution: BOFH Date: Fri, 23 Nov 2007 12:51:45 +0200 Message-Id: Cc: Mike Silbersack , current@freebsd.org Subject: Re: TCP RST+data! X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 23 Nov 2007 10:52:11 -0000 "Kip Macy" wrote: > On Nov 22, 2007 12:14 PM, Ian FREISLICH wrote: > > Hi > > > > I have a device (sip/iax phone) that has a web interface and a > > poorly documented CLI. The only thing is it sends a RST with its > > last data packet. "Stevens" seems to indicate an RST should discard > > buffered data and I suspect that's what's happening when I try to > > browse to it. > > > > However, Windows and MacOs both pull up the web page. Is this a > > bug in our TCP implimentation or in theirs? > > > > Here's a tcpdump of seamonkey trying to retrieve the document index: > > > > 22:07:53.728516 IP (tos 0x0, ttl 64, id 24507, offset 0, flags [DF], proto TCP (6), length 60) 196.7.162.28.50118 > 196.7.162.30.80: S, cksum 0xdbdd (corr ect), 2746220400:2746220400(0) win 65535 > > 22:07:53.731512 IP (tos 0x0, ttl 64, id 36, offset 0, flags [DF], proto TCP (6), length 60) 196.7.162.30.80 > 196.7.162.28.50118: S, cksum 0xbdba (correct ), 2416404465:2416404465(0) ack 2746220401 win 8192 > > 22:07:53.731543 IP (tos 0x0, ttl 64, id 24508, offset 0, flags [DF], proto TCP (6), length 52) 196.7.162.28.50118 > 196.7.162.30.80: ., cksum 0xe8f5 (corr ect), 1:1(0) ack 1 win 8326 > > 22:07:53.731593 IP (tos 0x0, ttl 64, id 24509, offset 0, flags [DF], proto TCP (6), length 428) 196.7.162.28.50118 > 196.7.162.30.80: P 1:377(376) ack 1 w in 8326 > > 22:07:53.770545 IP (tos 0x0, ttl 64, id 37, offset 0, flags [DF], proto TCP (6), length 52) 196.7.162.30.80 > 196.7.162.28.50118: ., cksum 0xe948 (correct ), 1:1(0) ack 377 win 7867 > > 22:07:54.004963 IP (tos 0x0, ttl 64, id 38, offset 0, flags [DF], proto TCP (6), length 61) 196.7.162.30.80 > 196.7.162.28.50118: P, cksum 0xcdea (correct ), 1:10(9) ack 377 win 8192 > > 22:07:54.018027 IP (tos 0x0, ttl 64, id 39, offset 0, flags [DF], proto TCP (6), length 638) 196.7.162.30.80 > 196.7.162.28.50118: RP 10:608(598) ack 377 win 8192 [!RST+ 200 OK\015\012Server: Rapid Logic/1.] > > Looking at your later trace, data with the RST is a red herring. The > only thing that stands out to me as being odd and perhaps is the > issue, is that the window size for the SYN and the ack are > inconsistent on FreeBSD but are consistent on OS X. I'm not sure off > hand where the number 8326 comes from. It could be that when the SIP's > stack is generating the ack for the GET it concludes that the window > accounting state is incorrect. > > Perhaps Mike can shed some light when he gets back online. I see. Playing around with net.inet.tcp sysctls, disabling delayed_ack fixes the problem with this phone. Do you think that this is a bug in the phone's TCP stack? Ian -- Ian Freislich