From owner-freebsd-hackers@FreeBSD.ORG Wed Aug 20 18:00:28 2008 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 2D5871065673 for ; Wed, 20 Aug 2008 18:00:28 +0000 (UTC) (envelope-from jav@sics.se) Received: from letter.sics.se (letter.sics.se [193.10.64.6]) by mx1.freebsd.org (Postfix) with ESMTP id E1D3B8FC1B for ; Wed, 20 Aug 2008 18:00:27 +0000 (UTC) (envelope-from jav@sics.se) Received: from [10.131.12.250] (unknown [12.19.192.51]) by letter.sics.se (Postfix) with ESMTP id D1262400DE for ; Wed, 20 Aug 2008 19:28:10 +0200 (CEST) From: Javier Ubillos To: freebsd-hackers@freebsd.org Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="=-CsJ8ctiSLLDT6E57DW1a" Date: Wed, 20 Aug 2008 10:27:49 -0700 Message-Id: <1219253269.9118.17.camel@dib> Mime-Version: 1.0 X-Mailer: Evolution 2.22.3.1 Subject: Override default ICMP (and other protocols) default replies. X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 20 Aug 2008 18:00:28 -0000 --=-CsJ8ctiSLLDT6E57DW1a Content-Type: text/plain Content-Transfer-Encoding: quoted-printable Hi freebsd-hackers. (Sorry for cross posting, but I got no reply when posting to freebsd-questions) I'm implementing a NAT (1 ip - 1 ip) like router. I have chosen to use pcaplib to pick up the packets. I have an implementation which picks up the packets, inspects them, rewrites the destination/source ip-addresses and sends them out on the repective interface. The problem I'm facing however is that my interfaces are answering to e.g. icmp-echo (ping) automatically, and I don't know how to turn this behaviour off. What I want to happen is that if A pings C, my router B in between should simply forward the packets w/o any automatic reactions. A --> B --> C So that if e.g. C is down, no echo-reply is sent back (or if C is up, that C is actually sending the echo-reply. Does any one know how to turn off the automatic replies (ICMP and whatever else I haven't forseen yet) or does any one know where I can find out more about the issue? Thank you // Javier --=-CsJ8ctiSLLDT6E57DW1a Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (GNU/Linux) iD8DBQBIrFQVGBo5FLRz4goRAm9aAKCFi7Byv/jZSGfXfP5orirnv8ETPQCeOLBN ofoxcJMimabFn+7MJlNXJX4= =GyOg -----END PGP SIGNATURE----- --=-CsJ8ctiSLLDT6E57DW1a--