From owner-freebsd-ipfw@FreeBSD.ORG  Sat Oct  4 09:01:06 2003
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From: "Roderick van Domburg" <r.s.a.vandomburg@student.utwente.nl>
To: <freebsd-ipfw@freebsd.org>
Date: Sat, 4 Oct 2003 18:02:10 +0200
Organization: University of Twente
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Subject: When to use setup keyword?
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Hello everyone,

I was pondering if blindly trailing every tcp rule with the 'setup' keyword
would incur any performance loss or security hazard.

I've got a server setup serving FTP, SSH, SMTP, DNS and HTTP. My rules in
question are the following:

allow tcp from any to {$ip} dst-port 21 setup
allow tcp from any to {$ip} dst-port 22 setup
allow tcp from any to {$ip} dst-port 25 setup
allow tcp from any to {$ip} dst-port 53 setup
allow tcp from any to {$ip} dst-port 80 setup

All services run just fine, but I was thinking that excluding 'setup' here
and there would make for a cleaner solution? For example, I don't think that
HTTP (even 1.1) requires the setup keyword does it?

Regards,

Roderick