From owner-freebsd-hackers Wed May 20 13:48:17 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id NAA22347 for freebsd-hackers-outgoing; Wed, 20 May 1998 13:48:17 -0700 (PDT) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from send1c.yahoomail.com (send1c.yahoomail.com [205.180.60.38]) by hub.freebsd.org (8.8.8/8.8.8) with SMTP id NAA22071 for ; Wed, 20 May 1998 13:46:49 -0700 (PDT) (envelope-from lc001@yahoo.com) Message-ID: <19980520204810.7890.rocketmail@send1c.yahoomail.com> Received: from [139.87.242.56] by send1c; Wed, 20 May 1998 13:48:10 PDT Date: Wed, 20 May 1998 13:48:10 -0700 (PDT) From: "L.C." Subject: Re: Questions about Packet Filter To: Mike Smith Cc: freebsd-hackers@FreeBSD.ORG MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Thanks a lot Mike. Are these BPF alike devices capable of "intercept" packages passing through them? I mean is it possible that after it intercepts the outgoing package it can modify the package contents(e.g. destination port) and inject into NIC? Or, modify the package contents when intercept the incoming packages and poll them back to the higher level protocols or applications? Carl ---Mike Smith wrote: > > > Very appreciated if anybody can answer the questions: > > > > 1. Does BPF support the monitoring of out going packages? how? I know > > it can monitor the receiving packages and directly write a new package > > into the specified network interface. How about the packages written > > by other network or transport protocols? > > Yes. A simple test would have show you this. > > > 2. Solaris seems having a similar soft-driver called "Network > > Interface Tap". Anybody use that before? Can it monitoring both > > incoming and outgoing packages? > > Yes. > > > 3. Any similar programming interface in the socket level? > > No. > > > 4. How about in HP-UX, Linux, and AIX? > > Most support something similar. > > > I may need to port my code to these OSs. > > Use libpcap, which provides a unified abstraction on top of most of > these platforms already. > > -- > \\ Sometimes you're ahead, \\ Mike Smith > \\ sometimes you're behind. \\ mike@smith.net.au > \\ The race is long, and in the \\ msmith@freebsd.org > \\ end it's only with yourself. \\ msmith@cdrom.com > > > == **_____________ Have a nice day _______________** _________________________________________________________ DO YOU YAHOO!? Get your free @yahoo.com address at http://mail.yahoo.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message