#!/bin/sh

# Internal Device = eth0
# Internal IP = 192.168.0.1

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# Copied from http://www.debian-administration.org/articles/23                 #
# "Setting up a simple Debian gateway"                      (modded a lot)     #
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PATH=/usr/sbin:/sbin:/bin:/usr/bin

#
# Delete All Existing Rules
#

iptables -F
iptables -t nat -F
iptables -t mangle -F
iptables -X

# Always accept loopback traffic
iptables -A INPUT -i lo -j ACCEPT

# Allow established connections, and those not coming from the outside
iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
iptables -A INPUT -m state --state NEW -i ! eth1 -j ACCEPT
iptables -A FORWARD -i eth1 -o eth0 -m state --state ESTABLISHED,RELATED -j ACCEPT

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# End of debian-administration iptables rules                                  #
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# Copied from http://www.debian-administration.org/articles/73                 #
# http://www.hackorama.com/network/portfwd.shtml
# "Port forwarding for iptables (DMZ)"             (Modded a lot)              #
# The instructions are for a different machine, I'm trying for this one.       #
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iptables -t nat -A PREROUTING -p tcp -i eth0 -d 192.168.0.195 --dport 7831 -j DNAT --to 192.168.0.195:7831

iptables -A FORWARD -p tcp -i eth0 -d 192.168.0.2 --dport 80 -j ACCEPT