From owner-freebsd-pf@FreeBSD.ORG Thu Jul 19 15:31:34 2012 Return-Path: Delivered-To: freebsd-pf@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 1BD5B1065675 for ; Thu, 19 Jul 2012 15:31:34 +0000 (UTC) (envelope-from tonix@interazioni.it) Received: from mx02.interazioni.net (mx02.interazioni.net [80.94.114.204]) by mx1.freebsd.org (Postfix) with ESMTP id 4C18E8FC29 for ; Thu, 19 Jul 2012 15:31:33 +0000 (UTC) Received: (qmail 84554 invoked by uid 88); 19 Jul 2012 15:24:50 -0000 Received: from unknown (HELO ?192.168.200.253?) (tonix@interazioni.it@217.19.151.67) by relay.interazioni.net with ESMTPA; 19 Jul 2012 15:24:50 -0000 Message-ID: <500826BD.3070602@interazioni.it> Date: Thu, 19 Jul 2012 17:24:45 +0200 From: "Tonix (Antonio Nati)" User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:13.0) Gecko/20120614 Thunderbird/13.0.1 MIME-Version: 1.0 To: freebsd-pf@freebsd.org Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit Subject: Question on packet filter using in and out interfaces X-BeenThere: freebsd-pf@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Technical discussion and general questions about packet filter \(pf\)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 19 Jul 2012 15:31:34 -0000 I have a basic question is on usage of 'in' or 'out' interfaces, on practical usage. I'm having some talks in PFsense mailing list, and I'm saying there is no security difference about using rulesets on output interfaces or on input interfaces, as PF is evaluating all rules in the same phase. At the opposite, I'm told all 'in' rules are evaluated first, than there is a routing phase, then the 'out' rules are finally evaluated, so it is more secure to have only filters on 'in' interfaces. Which is the real situation? Does really Packet Filter has any security advantage having only 'in' rules, or there is no difference on using out interface instead of in interface? All start from consideration that using out interfaces would semplify a lot management of complex environments, with interfaces dedicated to different customers (one OUT rule on specific interface instead of several IN rules on all other interfaces). Thanks for any clear answer you can give. Regards, Tonino