From owner-freebsd-security Mon Aug 21 14:37:17 2000 Delivered-To: freebsd-security@freebsd.org Received: from jade.chc-chimes.com (jade.chc-chimes.com [216.28.46.6]) by hub.freebsd.org (Postfix) with ESMTP id D6C4437B424 for ; Mon, 21 Aug 2000 14:37:14 -0700 (PDT) Received: by jade.chc-chimes.com (Postfix, from userid 1001) id 2366C1C07; Mon, 21 Aug 2000 17:37:14 -0400 (EDT) Date: Mon, 21 Aug 2000 17:37:14 -0400 From: Bill Fumerola To: William Wong Cc: freebsd-security@freebsd.org Subject: Re: icmptypes Message-ID: <20000821173714.D57333@jade.chc-chimes.com> References: <007701c00b4f$9c905340$4c9409cb@labyrinth.net.au> <003c01c00bb7$94783340$0300a8c0@anime.ca> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0i In-Reply-To: <003c01c00bb7$94783340$0300a8c0@anime.ca>; from willwong@anime.ca on Mon, Aug 21, 2000 at 05:34:25PM -0400 X-Operating-System: FreeBSD 3.3-STABLE i386 Sender: owner-freebsd-security@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org On Mon, Aug 21, 2000 at 05:34:25PM -0400, William Wong wrote: > Thanks for the responses. I've got a somewhat follow up question. > Instead of just dropping an icmp packet with say ipfw's deny rule, is there > a "polite" way to deny the packet. To clarify, I want to send an equivalent > of a "tcp reset" back, to let them know it's closed. Or is there no such > thing as this for the icmp protocol? I'm not that familiar with this > protocol as you can see. Instead of 'deny' use 'reset'. Of course, this opens you up to a multitude of DoS related problems, but you're at least being a good neighbor.... -- Bill Fumerola - Network Architect, BOFH / Chimes, Inc. billf@chimesnet.com / billf@FreeBSD.org To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-security" in the body of the message