From owner-freebsd-net@FreeBSD.ORG Wed Nov 19 20:24:09 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 403AF1065670 for ; Wed, 19 Nov 2008 20:24:09 +0000 (UTC) (envelope-from rrs@lakerest.net) Received: from lakerest.net (unknown [IPv6:2001:240:585:2:203:6dff:fe1a:4ddc]) by mx1.freebsd.org (Postfix) with ESMTP id 6FF998FC1B for ; Wed, 19 Nov 2008 20:24:08 +0000 (UTC) (envelope-from rrs@lakerest.net) Received: from [130.129.95.183] ([130.129.95.183]) (authenticated bits=0) by lakerest.net (8.14.1/8.14.1) with ESMTP id mAJKO3s8020952 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NOT); Wed, 19 Nov 2008 15:24:05 -0500 (EST) (envelope-from rrs@lakerest.net) DKIM-Signature: a=rsa-sha1; c=simple/simple; d=lakerest.net; s=mail; t=1227126246; h=Cc:Message-Id:From:To:In-Reply-To:Content-Type: Content-Transfer-Encoding:Mime-Version:Subject:Date:References: X-Mailer; b=c0oDlap3q0saWEjUrdi1W7LQKmZBrkrkQ59ECMGnaJLs+EsRBkVAk5E kC1S6ryUryTYdNi2hI4osjaKsqJkAkQ== Message-Id: From: Randall Stewart To: Luigi Rizzo In-Reply-To: <20081119153532.GB2910@onelab2.iet.unipi.it> Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes Content-Transfer-Encoding: 7bit Mime-Version: 1.0 (Apple Message framework v929.2) Date: Wed, 19 Nov 2008 15:24:02 -0500 References: <20081119153532.GB2910@onelab2.iet.unipi.it> X-Mailer: Apple Mail (2.929.2) Cc: freebsd-net Subject: Re: Thinking about UDP and tunneling 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, 19 Nov 2008 20:24:09 -0000 On Nov 19, 2008, at 10:35 AM, Luigi Rizzo wrote: > On Wed, Nov 19, 2008 at 10:00:27AM -0500, Randall Stewart wrote: >> Dear All: >> >> I have been contemplating UDP and tunneling. One of the >> things that is a nice feature in MacOS is the ability of >> a kernel module/extension to open a kernel level socket >> and have the mbuf chain that arrives for that port be passed >> in via a function. >> >> We use this in our MacOS version of the SCTP stack to do the >> UDP de-tunneling of SCTP packets. This is becoming a more and >> more common thing i.e. having transport protocols like SCTP and DCCP >> be tunneled over UDP to get by NAT's.... this actually sucks that >> this is necessary .. but it is what it is.... >> >> So, I am contemplating adding a similar sort of feature... basically >> provide an interface in UDP that a consumer (such as SCTP or DCCP) >> could >> use to "bind" a port and get UDP packets directly. >> >> What do you all think of the idea? > > the way (not the only one, but one way) this kind of things > can be done now is have ipfw select the traffic, and pass it > to one in-kernel natd instance, and after the work that Paolo Pisati > did for SoC 2005 (it think) the mechanism is extensible in > a relatively easy way to provide specific functions to do > the mmbuf manipulation. Interesting idea, but the destination of the packets MAY NOT be the same box the fw/nat is on. So this means I now have to enable ipfw/nat on all boxes that want to have tunneling.. Not exactly very friendly... > > >> That also reminds me.. who owns the ipfw code.. we actually >> have SCTP nat support that Jason But has done that we need to >> get in... >> >> I would be more than glad to shepherd this in if the owner >> of the code does not have the time... > > there isn't really a owner, over time different people including > myself have worked > on various aspects of the code -- if your changes affect only > natd extensions then Paolo Pisati (piso@) is probably a good > starting contact. You may want to have a look at the recent > and not-so-recent commit history to see who did other relevant > pieces of work such as dealing with locking, improving performance > in SMP and so on. I think it must be Paolo.. I will give him a ping R > > > cheers > luigi > ------------------------------ Randall Stewart 803-317-4952 (cell) 803-345-0391(direct)