From owner-freebsd-questions Tue Jan 14 0:32:29 2003 Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 0FB3C37B405 for ; Tue, 14 Jan 2003 00:32:28 -0800 (PST) Received: from mail.econolodgetulsa.com (mail.econolodgetulsa.com [198.78.66.163]) by mx1.FreeBSD.org (Postfix) with ESMTP id 6387943F1E for ; Tue, 14 Jan 2003 00:32:27 -0800 (PST) (envelope-from user@mail.econolodgetulsa.com) Received: from mail (user@mail [198.78.66.163]) by mail.econolodgetulsa.com (8.12.3/8.12.3) with ESMTP id h0E8WOZb062219 for ; Tue, 14 Jan 2003 00:32:24 -0800 (PST) (envelope-from user@mail.econolodgetulsa.com) Date: Tue, 14 Jan 2003 00:32:24 -0800 (PST) From: Josh Brooks To: freebsd-questions@freebsd.org Subject: ipfw rule help needed Message-ID: <20030114003015.G78856-100000@mail.econolodgetulsa.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG Hi, I am trying to create these two ipfw rules: deny all packets with an ack of zero deny all tcp packets with no MSS specified Can anyone show me the syntax to do that ? Also, comments on bad things that could happen if I put these in are appreciated. AFAIK, the only thing that can happen is that 1 in every 2^32 valid packets will be denied by the ack zero rule, and that the second rule will not affect anything except people using syn flood tools - since every valid tcp packet should have a MSS, right ? thanks. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message