ssh limit with iptables

ssh_limit.sh

#! /bin/bash

# this iptables rules sets an ssh limit of 4 per 60 seconds

IPT=`which iptables`

$IPT -A ssh_limit -p tcp -m recent --set --name ssh --rsource
$IPT -A ssh_limit -p tcp -m recent ! --rcheck --seconds 60 --hitcount 4 --name ssh --rsource -j ACCEPT
$IPT -A ssh_limit -j LOG --log-level info --log-prefix "SSH_LIMIT: "
$IPT -A ssh_limit -j DROP
     
# jump to the above chain inside the INPUT chain
$IPT -A INPUT -i eth0 -p tcp -s 0/0 --dport 22                    -j ssh_limit