From owner-freebsd-net@FreeBSD.ORG Sat Dec 4 14:41:21 2004 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 1446D16A4CE for ; Sat, 4 Dec 2004 14:41:21 +0000 (GMT) Received: from pi.codefab.com (pi.codefab.com [199.103.21.227]) by mx1.FreeBSD.org (Postfix) with ESMTP id B359043D62 for ; Sat, 4 Dec 2004 14:41:20 +0000 (GMT) (envelope-from cswiger@mac.com) Received: from [192.168.1.250] (pool-68-161-115-118.ny325.east.verizon.net [68.161.115.118]) by pi.codefab.com (8.12.11/8.12.11) with ESMTP id iB4EfDvr084386 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Sat, 4 Dec 2004 09:41:16 -0500 (EST) Message-ID: <41B1CC8A.6090509@mac.com> Date: Sat, 04 Dec 2004 09:41:14 -0500 From: Chuck Swiger Organization: The Courts of Chaos User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.3) Gecko/20040910 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Ian Smith References: In-Reply-To: X-Enigmail-Version: 0.86.1.0 X-Enigmail-Supports: pgp-inline, pgp-mime Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Status: No, hits=-4.5 required=5.5 tests=AWL,BAYES_00 autolearn=ham version=2.64 X-Spam-Checker-Version: SpamAssassin 2.64 (2004-01-11) on pi.codefab.com cc: freebsd-net@freebsd.org Subject: Re: ipfw and bridging [was: pf and bridging] 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: Sat, 04 Dec 2004 14:41:21 -0000 Ian Smith wrote: [ ... ] > Read those ones for interest, but it leaves me wondering: can you use > stateful filtering in ipfw, then? (here ipfw1 on a 4.8-RELEASE box with > BRIDGE in kernel so far, but I imagine this would apply also to ipfw2?) Yes, you ought to be able to perform stateful packet filtering with either ipfw1 or 2. > I'm aware that one can only filter incoming packets, so I've always > wondered whether stateful rules made any sense in a bridge context? A firewall filters packets which pass through it (ie, either via routing, bridging, or whatever the topology is). Yes, you can do stateful filtering on a bridge but you need to pay attention to the fact that you have both layer-2 and layer-3 traffic involved. You also need to enable a sysctl to have IPFW apply its rules to bridged traffic. -- -Chuck