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Date:      Tue, 22 Jan 2002 19:33:06 -0500
From:      Ray Kohler <rkohler1@cox.rr.com>
To:        freebsd-questions@FreeBSD.ORG
Subject:   Some questions about ipfw
Message-ID:  <0e9d45329001712FE6@Mail6.mgfairfax.rr.com>

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I have a protect-this-client-only firewall set up here,
and I'm not sure that my rules are good. It's very simple:

ipfw add allow ip from any to any via lo0
ipfw add allow tcp from me to any keep-state
ipfw add allow udp from me to any keep-state
ipfw add allow icmp from me to any keep-state
ipfw add allow icmp from any to me icmptype 3
ipfw add deny log ip from any to any

(No, I'm not using rc.firewall and not running natd.) I 
intend to let anything out and nothing in that isn't part 
of an established connection (and of course the ICMP type 3 packets).
I have 3 questions:

1) Why does the rc.firewall script use "setup" and "established" rules 
for tcp instead of keep-state like it does for udp?
2) Are these tules sufficient for my purpose?
3) I'm having trouble fetching ports even with
FETCH_CMD= fetch -p set in make.conf. Eventually I get the file, 
but not until after a lot of servers are tried. In my logs I see a lot of:

Jan 22 18:19:47 B1M1X9 /kernel: ipfw: 600 Deny TCP 199.232.41.9:20167 24.163.113.25:1039 in via rl0
Jan 22 18:19:49 B1M1X9 /kernel: ipfw: 600 Deny TCP 130.94.149.162:21 24.163.113.25:1032 in via rl0
Jan 22 18:19:59 B1M1X9 /kernel: ipfw: 600 Deny TCP 199.232.41.9:20167 24.163.113.25:1039 in via rl0
Jan 22 18:20:23 B1M1X9 /kernel: ipfw: 600 Deny TCP 199.232.41.9:20167 24.163.113.25:1039 in via rl0

where the "from" IPs belong to the about a dozen ftp servers I've tried,
and the packet arrives a few minutes after fetch has given up on that server.
(Why are these servers contacting me anyway when I'm using passive 
ftp, anyway?)

Thanks to all for reading such a long post.

-- 
Ray Kohler
Lewis's Law of Travel:
	The first piece of luggage out of the chute doesn't belong to
anyone, ever.

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