#
# 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
#
I.4. Пример rc.DHCP.firewall
#!/bin/sh
#
# rc.firewall – DHCP 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
#
################################################################## #########