From owner-freebsd-security@FreeBSD.ORG  Thu Mar 27 11:04:56 2003
Return-Path: <owner-freebsd-security@FreeBSD.ORG>
Delivered-To: freebsd-security@freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP id 7757737B401
	for <freebsd-security@freebsd.org>;
	Thu, 27 Mar 2003 11:04:56 -0800 (PST)
Received: from cirb503493.alcatel.com.au (c18609.belrs1.nsw.optusnet.com.au
	[210.49.80.204])
	by mx1.FreeBSD.org (Postfix) with ESMTP id 29AE543F75
	for <freebsd-security@freebsd.org>;
	Thu, 27 Mar 2003 11:04:55 -0800 (PST)
	(envelope-from peterjeremy@optushome.com.au)
Received: from cirb503493.alcatel.com.au (localhost.alcatel.com.au
	[127.0.0.1])h2RJ4rM2019942;	Fri, 28 Mar 2003 06:04:53 +1100 (EST)
	(envelope-from jeremyp@cirb503493.alcatel.com.au)
Received: (from jeremyp@localhost)
	by cirb503493.alcatel.com.au (8.12.8/8.12.8/Submit) id h2RJ4k4b019941;
	Fri, 28 Mar 2003 06:04:46 +1100 (EST)
Date: Fri, 28 Mar 2003 06:04:45 +1100
From: Peter Jeremy <peterjeremy@optushome.com.au>
To: Etienne Ledoux <etienne@unix.za.org>
Message-ID: <20030327190445.GC11307@cirb503493.alcatel.com.au>
References: <3E82142E.000017.64676@ns.interchange.ca>
	<1048774105.27599.15.camel@madcow>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <1048774105.27599.15.camel@madcow>
User-Agent: Mutt/1.4.1i
X-Spam-Status: No, hits=-30.1 required=5.0
	tests=AWL,EMAIL_ATTRIBUTION,IN_REP_TO,REFERENCES,
	      REPLY_WITH_QUOTES,USER_AGENT_MUTT
	autolearn=ham	version=2.50
X-Spam-Level: 
X-Spam-Checker-Version: SpamAssassin 2.50 (1.173-2003-02-20-exp)
cc: freebsd-security@freebsd.org
Subject: Re: Multiple Firewalls with ipfilter?
X-BeenThere: freebsd-security@freebsd.org
X-Mailman-Version: 2.1.1
Precedence: list
List-Id: Security issues [members-only posting]
	<freebsd-security.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-security>,
	<mailto:freebsd-security-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-security>
List-Post: <mailto:freebsd-security@freebsd.org>
List-Help: <mailto:freebsd-security-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-security>,
	<mailto:freebsd-security-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Thu, 27 Mar 2003 19:04:57 -0000

On Thu, Mar 27, 2003 at 04:08:23PM +0200, Etienne Ledoux wrote:
>Both master and slave firewalls are exactly the same except for my
>second firewall had to extra rules right at the top:
>
># Allow all established connections
>pass in quick proto tcp all flags A/SA keep state keep frags
>pass out quick proto tcp all flags A/SA keep state keep frags
>#pass in quick proto udp all keep state keep frags
>#pass out quick proto udp all keep state keep frags

This means you've lost all the benefits of stateful packet filtering
(and the above is a fairly big security hole since you're allowing any
connection spoofing attempts to succeed).

This also doesn't address NAT state tables - which is critical for me.

Peter