From owner-freebsd-net Fri Apr 28 1: 2:19 2000 Delivered-To: freebsd-net@freebsd.org Received: from relay.ucb.crimea.ua (relay.ucb.crimea.ua [212.110.138.1]) by hub.freebsd.org (Postfix) with ESMTP id BA8B937B83A for ; Fri, 28 Apr 2000 01:02:05 -0700 (PDT) (envelope-from ru@ucb.crimea.ua) Received: (from ru@localhost) by relay.ucb.crimea.ua (8.9.3/8.9.3/UCB) id KAA27962; Fri, 28 Apr 2000 10:57:35 +0300 (EEST) (envelope-from ru) Date: Fri, 28 Apr 2000 10:57:35 +0300 From: Ruslan Ermilov To: Archie Cobbs Cc: julian@elischer.org, brian@Awfulhak.org, cmott@scientech.com, ari@suutari.iki.fi, perhaps@yes.no, net@FreeBSD.ORG, Erik Salander Subject: Re: Improved PPTP support for libalias(3) Message-ID: <20000428105735.A20760@relay.ucb.crimea.ua> Mail-Followup-To: Archie Cobbs , julian@elischer.org, brian@Awfulhak.org, cmott@scientech.com, ari@suutari.iki.fi, perhaps@yes.no, net@FreeBSD.ORG, Erik Salander References: <20000419115513.A42767@relay.ucb.crimea.ua> <200004191819.LAA27198@bubba.whistle.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.95.3i In-Reply-To: <200004191819.LAA27198@bubba.whistle.com>; from Archie Cobbs on Wed, Apr 19, 2000 at 11:19:33AM -0700 Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org On Wed, Apr 19, 2000 at 11:19:33AM -0700, Archie Cobbs wrote: > Ruslan Ermilov writes: > > > Sure there is: the Call ID. > > > > > > We are probably going to implement the remaining bit of this here > > > at Whistle in the next couple of weeks.. and will submit when done. > > > > > This patch should (hopefully) allow for concurrent PPTP tunnels from > > multiple local PACs to the same remote PNS to work behind NAT (rfc2637 > > terminology is being used). > > > > Could someone please test this patch, since I do not have enough test > > environment here? > > > > Note please, that you DO NOT need PacketAliasRedirectPptp() for this > > to work. Just running natd(8) with the default set of options should > > be enough. > > > > If someone is going to test this, please mail me the output of `natd -v' > > while trying PPTP to the same PNS from two or more local PACs. > > I'm not that familiar with the libalias code (erik@whistle.com is > more familiar), but am familiar with PPTP. Are you swizzling the > TCP stream (port 1723) at all? If not, then it's probably not going > to work .. or at least, not when two clients use the same Call ID. > > PPTP is like active mode FTP in that the Call ID (FTP -> port #) is > embedded in the TCP stream and must be swizzled. Unlike FTP however, > the TCP stream won't shrink or expand. > Well, I have some spare time now, and if you (at Whistle) did not start this work yet, I could probably do it. I am not that familiar with PPTP (read: have no practical experience) like you, and if you could give me an exact algorithm (in terms of RFC 2637) how/what to intercept/alias/dealias, I will implement it in libalias(3). Also, is the poptop/pptpclient pair from the ports collection a good enough test bed? As a first step, I would like to get rid of PacketAliasRedirectPptp() and replace it with more generic PacketAliasRedirectProto(). Cheers, -- Ruslan Ermilov Sysadmin and DBA of the ru@ucb.crimea.ua United Commercial Bank, ru@FreeBSD.org FreeBSD committer, +380.652.247.647 Simferopol, Ukraine http://www.FreeBSD.org The Power To Serve http://www.oracle.com Enabling The Information Age To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message