From owner-freebsd-questions Sun Sep 12 19:23:22 1999 Delivered-To: freebsd-questions@freebsd.org Received: from gndrsh.dnsmgr.net (GndRsh.dnsmgr.net [198.145.92.4]) by hub.freebsd.org (Postfix) with ESMTP id 4608014C7F; Sun, 12 Sep 1999 19:23:17 -0700 (PDT) (envelope-from freebsd@gndrsh.dnsmgr.net) Received: (from freebsd@localhost) by gndrsh.dnsmgr.net (8.9.3/8.9.3) id TAA31984; Sun, 12 Sep 1999 19:22:29 -0700 (PDT) (envelope-from freebsd) From: "Rodney W. Grimes" Message-Id: <199909130222.TAA31984@gndrsh.dnsmgr.net> Subject: Re: How to prevent motd including os info In-Reply-To: <199909130110.VAA27314@khavrinen.lcs.mit.edu> from Garrett Wollman at "Sep 12, 1999 09:10:47 pm" To: wollman@khavrinen.lcs.mit.edu (Garrett Wollman) Date: Sun, 12 Sep 1999 19:22:28 -0700 (PDT) Cc: des@flood.ping.uio.no (Dag-Erling Smorgrav), nate@mt.sri.com (Nate Williams), ben@scientia.demon.co.uk (Ben Smithurst), jramirez@digicomsystems.net (Jeremy L. Ramirez), dev-null@ns1.digicomsystems.net, freebsd-questions@FreeBSD.ORG, freebsd-security@FreeBSD.ORG X-Mailer: ELM [version 2.4ME+ PL54 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > < said: > > > +tcp_drop_synfin="NO" # Set to YES to drop TCP packets with SYN+FIN > > + # NOTE: this breaks rfc1644 extensions (T/TCP) > > No, it breaks TCP, period, regardless of RFC 1644. Christmas-tree > segments are perfectly valid in TCP (i.e., SYN URG PSH FIN). Okay, are SYN * ^URG * ^PSH * FIN packets, another words packets with just the SYN and FIN bits set, but not the others used anyplace other than in T/TCP aka rfc1644? -- Rod Grimes - KD7CAX - (RWG25) rgrimes@gndrsh.dnsmgr.net To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message