#!/bin/sh # default iptables -P INPUT ACCEPT iptables -P FORWARD ACCEPT iptables -P OUTPUT ACCEPT # flush iptables -t filter -F INPUT iptables -t filter -F FORWARD iptables -t filter -F OUTPUT iptables -t nat -F PREROUTING iptables -t nat -F POSTROUTING # aktivere masquerade iptables -t nat -A POSTROUTING -j MASQUERADE -p icmp iptables -t nat -A POSTROUTING -j MASQUERADE -p udp iptables -t nat -A POSTROUTING -j MASQUERADE -p tcp iptables -t nat -A PREROUTING -s ! 10.4.0.0/16 -p tcp --dport 20 -j DNAT --to-destination 10.4.0.3 iptables -t nat -A PREROUTING -s ! 10.4.0.0/16 -p tcp --dport 21 -j DNAT --to-destination 10.4.0.3 iptables -t nat -A PREROUTING -s ! 10.4.0.0/16 -p tcp --dport 22 -j DNAT --to-destination 10.4.0.3 iptables -t nat -A PREROUTING -s ! 10.4.0.0/16 -p tcp --dport 25 -j DNAT --to-destination 10.4.0.3 iptables -t nat -A PREROUTING -s ! 10.4.0.0/16 -p tcp --dport 80 -j DNAT --to-destination 10.4.0.3 iptables -t nat -A PREROUTING -s ! 10.4.0.0/16 -p tcp --dport 110 -j DNAT --to-destination 10.4.0.3