#

# Accept the packets we actually want to forward

#

$IPTABLES -A FORWARD -i $LAN_IFACE -j ACCEPT

$IPTABLES -A FORWARD -m state –state ESTABLISHED,RELATED -j ACCEPT

#

# Log weird packets that don't match the above.

#

$IPTABLES -A FORWARD -m limit –limit 3/minute –limit-burst 3 -j LOG \

–log-level DEBUG –log-prefix "IPT FORWARD packet died: "

#

# 4.1.6 OUTPUT chain

#

#

# Bad TCP packets we don't want.

#

$IPTABLES -A OUTPUT -p tcp -j bad_tcp_packets

#

# Special OUTPUT rules to decide which IP's to allow.

#

$IPTABLES -A OUTPUT -p ALL -s $LO_IP -j ACCEPT

$IPTABLES -A OUTPUT -p ALL -s $LAN_IP -j ACCEPT

$IPTABLES -A OUTPUT -p ALL -s $INET_IP -j ACCEPT

#

# Log weird packets that don't match the above.

#

$IPTABLES -A OUTPUT -m limit –limit 3/minute –limit-burst 3 -j LOG \

–log-level DEBUG –log-prefix "IPT OUTPUT packet died: "

######

# 4.2 nat table

#

#

# 4.2.1 Set policies

#

#

# 4.2.2 Create user specified chains

#

#

# 4.2.3 Create content in user specified chains

#

#

# 4.2.4 PREROUTING chain

#

#

# 4.2.5 POSTROUTING chain

#

#

# Enable simple IP Forwarding and Network Address Translation

#

$IPTABLES -t nat -A POSTROUTING -o $INET_IFACE -j SNAT –to-source $INET_IP

#

# 4.2.6 OUTPUT chain

#

######

# 4.3 mangle table

#

#

# 4.3.1 Set policies

#

#

# 4.3.2 Create user specified chains

#

#

# 4.3.3 Create content in user specified chains

#

#

# 4.3.4 PREROUTING chain

#

#

# 4.3.5 INPUT chain

#

#

# 4.3.6 FORWARD chain

#

#

# 4.3.7 OUTPUT chain

#

#

# 4.3.8 POSTROUTING chain

#

#!/bin/sh

#

# rc.DMZ.firewall – DMZ IP Firewall script for Linux 2.4.x and iptables

#

# Copyright (C) 2001 Oskar Andreasson <bluefluxATkoffeinDOTnet>

#

# This program is free software; you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation; version 2 of the License.

#

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

# GNU General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program or from the site that you downloaded it

# from; if not, write to the Free Software Foundation, Inc., 59 Temple

# Place, Suite 330, Boston, MA 02111-1307 USA

#

###########################################################################

#

# 1. Configuration options.

#

#

# 1.1 Internet Configuration.

#

INET_IP="194.236.50.152"

HTTP_IP="194.236.50.153"

DNS_IP="194.236.50.154"

INET_IFACE="eth0"

#

# 1.1.1 DHCP

#

#

# 1.1.2 PPPoE

#

#

# 1.2 Local Area Network configuration.

#

# your LAN's IP range and localhost IP. /24 means to only use the first 24

# bits of the 32 bit IP address. the same as netmask 255.255.255.0

#

LAN_IP="192.168.0.1"

LAN_IFACE="eth1"

#

# 1.3 DMZ Configuration.

#

DMZ_HTTP_IP="192.168.1.2"