[SEM05][ASK-LAB2] iptables config script

#!/bin/bash
#CZYSZCZENIE REGUL
iptables -F
iptables -F -t nat
iptables -X -t nat
iptables -F -t filter
iptables -X -t filter

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

iptables -A INPUT -i lo -j ACCEPT
iptables -A INPUT -i eth1 -j ACCEPT
iptables -A INPUT -i eth0 -s 192.168.56.101 -j DROP
iptables -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
#OTWARCIE PORTU oraz PRZEKIEROWANIE GO
iptables -A INPUT -p tcp -m state --state NEW -m tcp --dport 1234 -j ACCEPT
echo "1">/proc/sys/net/ipv4/ip_forward
iptables -A FORWARD -i eth1 -o eth0 -s 192.168.1.0/255.255.255.0 -d 0/0 -j ACCEPT
iptables -A FORWARD -i eth0 -o eth1 -s 0/0 -d 192.168.1.0/255.255.255.0 -j ACCEPT
iptables -t nat -A POSTROUTING -s 192.168.1.0/255.255.255.0 -d 0/0 -j MASQUERADE

iptables -A PREROUTING -t nat -i eth0 -p tcp -d 192.168.56.101 --dport 1234 -j DNAT --to-destination 192.168.1.3:22
iptables -A PREROUTING -t nat -i eth1 -p tcp -d 192.168.56.101 --dport 1234 -j DNAT --to-destination 192.168.1.3:22

iptables -A FORWARD -i eth1 -o eth1 -j ACCEPT