From owner-freebsd-hackers@FreeBSD.ORG  Sat Jun 19 10:40:34 2004
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Date: Sat, 19 Jun 2004 13:40:20 +0300
From: Viktor Ivanov <viktor.ivanov@gmail.com>
To: freebsd-hackers@freebsd.org
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Subject: ipfw2 test utility
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Hello -hackers.

I'm thinking about an utility to test a simple packet against the
machine's firewall (ipfw2 to be more specific). I needed it because on
some of my routers the configuration got complicated and the rule
count is too high. And sometimes I need to see quickly what a
colleague have done to the firewall and why it's not working as
expected.

Is there an (easy) way to take the packet-matching code from the
kernel and use it to check a (manually) constructed packet on the
current ipfw2 rule set?

I was planning on writing a simple script that reads the output of
`ipfw list' and then does some very simple checks. Mostly I need to
look what's done to packets from certain address/network coming from a
certain interface. Sometimes I need to check on tcp streams too.

Maybe I should just write a good script to build proper rule sets and
not try to fix a problem by creating more problems :)

Any comments are welcome