From owner-freebsd-ipfw Thu Apr 20 8:51:26 2000 Delivered-To: freebsd-ipfw@freebsd.org Received: from mail.rz.fh-wilhelmshaven.de (mail.rz.fh-wilhelmshaven.de [139.13.25.134]) by hub.freebsd.org (Postfix) with ESMTP id 0D52237B8B0 for ; Thu, 20 Apr 2000 08:51:22 -0700 (PDT) (envelope-from ohoyer@fbwi.fh-wilhelmshaven.de) Received: from fettesau.stuwo.fh-wilhelmshaven.de (stuwopc5.stuwo.fh-wilhelmshaven.de [139.13.209.5]) by mail.rz.fh-wilhelmshaven.de (8.9.3/8.9.3) with SMTP id RAA12960; Thu, 20 Apr 2000 17:51:06 +0200 (MET DST) Message-Id: <4.1.20000420174210.00aacec0@mail.rz.fh-wilhelmshaven.de> X-Sender: ohoyer@mail.rz.fh-wilhelmshaven.de X-Mailer: QUALCOMM Windows Eudora Pro Version 4.1 Date: Thu, 20 Apr 2000 17:45:49 +0200 To: Gregory Bond From: Olaf Hoyer Subject: Re: Pinging Firewall Cc: freebsd-ipfw@FreeBSD.ORG In-Reply-To: <200004192337.JAA25250@lightning.itga.com.au> References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-freebsd-ipfw@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG At 09:37 20.04.00 +1000, you wrote: >> Question: In which ways does a firewall handles pings? > >It is part of the low-level networking code in the kernel. > >> And, more important, in which phase of the TCP/IP receiving process of the >> ping may it be blocked? > >Ping has nothing to do with TCP. Ping uses ICMP packets. > >You can block pings using the appropriate rules in ipfw. > Hi! Sorry, really had the head full with other stuff... Had also to care last days about protocols like Netbios/Netbeui, so TCP/IP was just the opposite to that.... ;-) Are there any good sources, describing in detail, in which phase of the receiving process IP/ICMP/UDP packets are possible to filter/block? (Others than the 4.x BSD book, preferrably online...) Regards Olaf Hoyer -------- Olaf Hoyer www.nightfire.de mailto:Olaf.Hoyer@nightfire.de FreeBSD- Turning PC's into workstations ICQ:22838075 Liebe und Hass sind nicht blind, aber geblendet vom Feuer, dass sie selber mit sich tragen. (Nietzsche) To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-ipfw" in the body of the message