From owner-freebsd-questions@FreeBSD.ORG  Thu Aug  4 21:03:11 2005
Return-Path: <owner-freebsd-questions@FreeBSD.ORG>
X-Original-To: freebsd-questions@freebsd.org
Delivered-To: freebsd-questions@freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP id 7B99A16A41F
	for <freebsd-questions@freebsd.org>;
	Thu,  4 Aug 2005 21:03:11 +0000 (GMT)
	(envelope-from pauls@utdallas.edu)
Received: from smtp1.utdallas.edu (smtp1.utdallas.edu [129.110.10.12])
	by mx1.FreeBSD.org (Postfix) with ESMTP id 3BCFE43D45
	for <freebsd-questions@freebsd.org>;
	Thu,  4 Aug 2005 21:03:11 +0000 (GMT)
	(envelope-from pauls@utdallas.edu)
Received: from utd59514.utdallas.edu (utd59514.utdallas.edu [129.110.3.28])
	by smtp1.utdallas.edu (Postfix) with ESMTP id CE6DF388E94
	for <freebsd-questions@freebsd.org>;
	Thu,  4 Aug 2005 16:03:10 -0500 (CDT)
Date: Thu, 04 Aug 2005 16:03:10 -0500
From: Paul Schmehl <pauls@utdallas.edu>
To: freebsd-questions@freebsd.org
Message-ID: <C1F7FA7264DF76F53A475500@utd59514.utdallas.edu>
In-Reply-To: <A1225E310DA8DA9B86364FA0@utd59514.utdallas.edu>
References: <A1225E310DA8DA9B86364FA0@utd59514.utdallas.edu>
X-Mailer: Mulberry/3.1.6 (Linux/x86)
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii; format=flowed
Content-Transfer-Encoding: 7bit
Content-Disposition: inline
Subject: Re: Shell script question
X-BeenThere: freebsd-questions@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: User questions <freebsd-questions.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-questions>, 
	<mailto:freebsd-questions-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-questions>
List-Post: <mailto:freebsd-questions@freebsd.org>
List-Help: <mailto:freebsd-questions-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-questions>, 
	<mailto:freebsd-questions-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Thu, 04 Aug 2005 21:03:11 -0000

--On Thursday, August 04, 2005 12:46:20 -0500 Paul Schmehl 
<pauls@utdallas.edu> wrote:

> I'm working on a shell script to use p0f to identify "unauthorized" hosts
> on our network.
>
> In the script I use an echo command to see what the output of the command
> is.  This is what it looks like:
> /usr/local/bin/p0f -i xl0 -N -l -o /root/capture.1123177152.log 'src net
> 10.0.0.0/8 or src net 129.110.0.0/16'
>
> If I paste the output of the echo command to the cli and hit enter, p0f
> runs and writes to the log.  Yet when I actually try to run that same
> command from the script, p0f complains:
>
> pcap_compile: illegal token: '
> See man tcpdump or p0f README for help on bpf filter expressions.
>
> Here's the script.  It's very simple right now, but there's a lot more
> work to be done.  I first have to figure out this problem, though:
>
># !/bin/sh
>
> P0F=/usr/local/bin/p0f
> EPOCH_DATE=`date -j -f "%a %b %d %T %Z %Y" "\`date\`" "+%s"`
> LOG=/root/capture.${EPOCH_DATE}.log
> NIC="-i xl0"
> ARGS="-N -l -o ${LOG}"
> DAEMON="-d"
> FILTER="'src net 10.0.0.0/8 or src net 129.110.0.0/16'"
>
> echo "${P0F} ${NIC} ${ARGS} ${DAEMON} ${FILTER}"
> ${P0F} ${NIC} ${ARGS} ${FILTER}
>
> Why is p0f complaining about the bpf filter?  I've tried escaping the
> single quotes, but that generates a different error.  I don't understand
> why the identical command works on the cli, but not in the script.
>
For the record, `eval ${P0F} ${NIC} ${ARGS} ${DAEMON} ${FILTER}` solved the 
problem.

Paul Schmehl (pauls@utdallas.edu)
Adjunct Information Security Officer
University of Texas at Dallas
AVIEN Founding Member
http://www.utdallas.edu/ir/security/