From owner-freebsd-net@FreeBSD.ORG Fri Mar 4 16:21:52 2005 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 5AAD616A4CE; Fri, 4 Mar 2005 16:21:52 +0000 (GMT) Received: from stephanie.unixdaemons.com (stephanie.unixdaemons.com [67.18.111.194]) by mx1.FreeBSD.org (Postfix) with ESMTP id BA99043D31; Fri, 4 Mar 2005 16:21:51 +0000 (GMT) (envelope-from bmilekic@technokratis.com) Received: from stephanie.unixdaemons.com (bmilekic@localhost.unixdaemons.com [127.0.0.1])j24GLnt2090689; Fri, 4 Mar 2005 11:21:49 -0500 (EST) Received: (from bmilekic@localhost) by stephanie.unixdaemons.com (8.13.3/8.12.1/Submit) id j24GLn9I090688; Fri, 4 Mar 2005 11:21:49 -0500 (EST) (envelope-from bmilekic@technokratis.com) X-Authentication-Warning: stephanie.unixdaemons.com: bmilekic set sender to bmilekic@technokratis.com using -f Date: Fri, 4 Mar 2005 11:21:49 -0500 From: Bosko Milekic To: Aziz KEZZOU Message-ID: <20050304162149.GA90499@technokratis.com> References: <37e13166050304080715525d7e@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <37e13166050304080715525d7e@mail.gmail.com> User-Agent: Mutt/1.4.2.1i cc: freebsd-net@freebsd.org cc: hackers@freebsd.org Subject: Re: generic network protocols parser ? X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 04 Mar 2005 16:21:52 -0000 On Fri, Mar 04, 2005 at 11:07:34AM -0500, Aziz KEZZOU wrote: > Hi all, > I am wondering if any one knows about a generic parser which takes a > packet (mbuf) of a certain protocol (e.g RSVP ) as input and generates > some data structre representing the packet ? > > I've been searching for a while and found that ethereal and tcpdump > for example use specific data structres and functions to dissect each > protocol packets. Is this the only approach possible ? > > My supervisor suggested using a TLV (Type/Length/Value) approach > instead. Any opinions about that? > > If no such a parser exists is there any practical reason why ? > > Thanks, > Aziz You can only go so far with generic parsing. Eventually you will want some protocol specific value to be extracted and your parser will have to know about what the packet looks like. What are you trying to do, exactly? -- Bosko Milekic bmilekic@technokratis.com bmilekic@FreeBSD.org