iptables cron script for Rutgers known attackers list

rutgers-drop-list.sh

#!/bin/bash

IPTABLES=$(which iptables)
URL="http://report.rutgers.edu/DROP/attackers"
FILE="/tmp/rutgers-drop-list.txt"
CHAIN="RUTGERSDROP";

# check if chain exists
$IPTABLES -L $CHAIN -n
if [ $? -eq 0 ]; then
    $IPTABLES -F $CHAIN

    echo "Flushed old rules"
else
    $IPTABLES -N $CHAIN
    $IPTABLES -A INPUT -j $CHAIN
    $IPTABLES -A FORWARD -j $CHAIN

    echo "Creating new chain"
fi;

wget -qc $URL -O $FILE

for IP in $(cat $FILE | egrep -v '^;' | awk '{ print $1}'); do
    $IPTABLES -A $CHAIN -p all -s $IP -j DROP
    echo "Added drop rule for $IP"
done

unlink $FILE

echo "Finished"