From owner-freebsd-security@FreeBSD.ORG  Wed Sep 24 08:56:14 2003
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Date: Wed, 24 Sep 2003 08:56:13 -0700
From: Michael Sierchio <kudzu@tenebras.com>
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Subject: Possible (or possibly painful) workaround for FreeBSD-SA-03:14.arp
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Of course you should patch/upgrade, etc.  A stopgap measure
could be to use static ARP for a segment.  I have done this
for a long time with wireless hosts, since I'm in an urban
environment with many visible nodes, some in autos, and
ARP cache poisoning is a well-known DoS against wireless.

You may find it extremely painful and less-than-useful to
have static IP addrs, etc. for hosts.

Here's a snippet of /usr/local/etc/rc.d/20-statarp.sh from
my FreeBSD host (192.168.1.1) serving as a wireless router


#! /bin/sh

PATH=/usr/sbin:/sbin

ifconfig wi0 -arp
arp -d -a  2>&1 > /dev/null

# wireless NICs

arp -s 192.168.1.1   00:02:2d:0e:00:40 2>&1 > /dev/null
arp -s 192.168.1.129 00:30:ab:14:11:46 2>&1 > /dev/null
arp -s 192.168.1.130 00:30:ab:14:11:f6 2>&1 > /dev/null

###$# many entries deleted ...

arp -s 192.168.1.195 00:30:ab:14:0f:89 2>&1 > /dev/null

# end