#! /bin/sh
# List of MAC Addresses to drop
mac="XX:XX:XX:XX:XX:XX AA:AA:AA:AA:AA:AA"

set -- $mac

# while [ -n "$1" ]; do
while [ $# -gt 0 ]; do
  echo "iptables -I FORWARD -m mac --mac-source $1 -j DROP">>/etc/firewall.user
  shift
done