From owner-freebsd-net@FreeBSD.ORG Wed Aug 20 21:03:48 2008 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 850A51065676 for ; Wed, 20 Aug 2008 21:03:48 +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 480468FC1E for ; Wed, 20 Aug 2008 21:03:48 +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 83EF240105 for ; Wed, 20 Aug 2008 22:44:42 +0200 (CEST) From: Javier Ubillos To: freebsd-net@freebsd.org Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="=-vvA1bPIV4wkv8/Mvi1W1" Date: Wed, 20 Aug 2008 13:44:21 -0700 Message-Id: <1219265061.9118.29.camel@dib> Mime-Version: 1.0 X-Mailer: Evolution 2.22.3.1 Subject: erride default ICMP (and other protocols) default replies. X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 20 Aug 2008 21:03:48 -0000 --=-vvA1bPIV4wkv8/Mvi1W1 Content-Type: text/plain Content-Transfer-Encoding: quoted-printable Hi freebsd-net. (Sorry for cross posting. This time I think I found the right forum for my question) I'm implementing a NAT (1 ip - 1 ip) like router. (it's not actually NAT, but it's a good analogy for this case). 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 --=-vvA1bPIV4wkv8/Mvi1W1 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) iD8DBQBIrIIlGBo5FLRz4goRAv9TAKCKrhJqaueMiFUIeMG1TQghqTSyfQCfbPMU XWdayAjd4c+tnTcL9R6fIsY= =kvgh -----END PGP SIGNATURE----- --=-vvA1bPIV4wkv8/Mvi1W1--