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Date:      Sun, 17 May 1998 14:00:49 -0500 (CDT)
From:      Charlie Root <root@ftp1.mfn.org>
To:        freebsd-questions@FreeBSD.ORG
Subject:   Possible bug in IPFW
Message-ID:  <199805171900.OAA07502@ftp1.mfn.org>

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As everyone on this list knows, we've been playing with IPFW pretty
intensely over the last couple of days.  Having finalized our rule
sets, we went about a stress-test (sans appreciable load) yesterday.

Here is the basic outline:

(1) Rulesets.  Allow this, that, blah, blah, blah...
(2) Final rule: 65500 deny log all from any to any

So we bring up the filter machine, and start attacking it:

(3) First, (and last it turns out), we scan it twice, first on port
1080, and second on port 23 (dont ask why these ports, it's a long
story). The scan consists of attempting to establish connections
(i.e., *not* a "stealth" scanner) at each address of our ip blocks.

About half way through the "23 series" of scans (which would make it
about 750 connections attempted, it ceased logging (forever!) with the 
following message:

May 17 00:39:21 attackme /kernel: ipfw: 65500 Deny TCP x.x.x.x:1065 me.me.me.me:23 in via de3

I have checked for disk space, which AFAIK has never exceeded 50% usage on any
slice, and sure enough, the top user of space was at a mere 45%.  /var is at 3%.

Except for the fact that it is no longer logging, it appears to be ok: cron
is running and doing it's thing, it succeeded in backing itself up last night,
and it still appears to be filtering, although *without* logging bad packets.

Should I be forwarding this to the bugs list, or have I missed something
very basic here?

TIA

J.A. Terranson
sysadmin@mfn.org

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