Where to store iptables script

[Jacob Friis Larsen <jfl@list.idg.dk>]

By the help of http://iptables-script.dk/ I have created the script below.
Where should I store it?
And does it look ok?
Thanks, Jacob


#!/bin/sh

# Disable forwarding
echo 0 > /proc/sys/net/ipv4/ip_forward

# load some modules (if needed)
modprobe ip_nat_ftp
modprobe ip_conntrack_ftp

# Flush
iptables -t nat -F POSTROUTING
iptables -t nat -F PREROUTING
iptables -t nat -F OUTPUT
iptables -F

iptables -P INPUT DROP
iptables -P FORWARD DROP
iptables -P OUTPUT ACCEPT

#localhost
iptables -A INPUT -i lo -j ACCEPT
iptables -A OUTPUT -o lo -j ACCEPT

# Open ports on router for server/services
iptables -A INPUT -s 1.2.3.4 -j ACCEPT -p tcp --dport 20
iptables -A INPUT -s 1.2.3.4 -j ACCEPT -p tcp --dport 21
iptables -A INPUT -j ACCEPT -p tcp --dport 22
iptables -A INPUT -j ACCEPT -p tcp --dport 25
iptables -A INPUT -j ACCEPT -p tcp --dport 80
iptables -A INPUT -j ACCEPT -p tcp --dport 143
iptables -A INPUT -j ACCEPT -p tcp --dport 993

# STATE RELATED for router
iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT

# Enable forwarding
echo 1 > /proc/sys/net/ipv4/ip_forward