#!/bin/bash
LAN=192.168.0.0/24
 
modprobe ip_tables
modprobe iptable_filter
modprobe iptable_mangle
modprobe iptable_nat
modprobe ip_conntrack_ftp
modprobe ip_nat_ftp
 
iptables -F
iptables -Z
iptables -X
iptables -t nat -F
 
iptables -P INPUT DROP
iptables -P FORWARD DROP
 
iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE
echo 1 > /proc/sys/net/ipv4/ip_forward
echo 1 > /proc/sys/net/ipv4/ip_dynaddr
 
iptables -t mangle -A OUTPUT -o eth0 -p tcp -m multiport --dports 80,22 -j TOS --set-tos 0x10
 
iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
iptables -A INPUT  -i lo -j ACCEPT
 
iptables -A INPUT -i eth0 -p tcp --dport 22 -j ACCEPT
iptables -A INPUT -i eth0 -p tcp --dport 80 -j ACCEPT
 
iptables -A INPUT -i eth1 -p tcp --dport 25 -j ACCEPT
iptables -A INPUT -i eth1 -p tcp --dport 110 -j ACCEPT
iptables -A INPUT -i eth1 -p tcp --dport 143 -j ACCEPT
iptables -A INPUT -i eth1 -p tcp --dport 22 -j ACCEPT
iptables -A INPUT -i eth1 -p tcp --dport 445 -j ACCEPT
 
iptables -A INPUT -i eth1 -p tcp --dport 3128 -j ACCEPT
iptables -A INPUT -i eth1 -p icmp -j ACCEPT
 
iptables -A FORWARD -m state --state ESTABLISHED,RELATED -j ACCEPT
 
iptables -A FORWARD -i eth0 -p tcp --dport 3389 -j ACCEPT
iptables -A FORWARD -i eth0 -p tcp --dport 5631 -j ACCEPT
iptables -A FORWARD -i eth0 -p tcp --dport 5632 -j ACCEPT
iptables -A FORWARD -i eth0 -p tcp --dport 25 -j ACCEPT
 
iptables -A FORWARD -i eth1 -p tcp --dport 53 -j ACCEPT
iptables -A FORWARD -i eth1 -p udp --dport 53 -j ACCEPT
iptables -A FORWARD -i eth1 -p tcp --dport 443 -j ACCEPT
 
iptables -t nat -A PREROUTING -i eth0 -p tcp --dport 25 -j DNAT --to 192.168.0.253