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发信人: lofe (〖感激生活Θ垃圾桶〗), 信区: Linux
标  题: IPtable 1.0.7指南(五)
发信站: 哈工大紫丁香 (2001年12月11日13:46:52 星期二), 站内信件

#
# PREROUTING chain.
#
# Do some checks for obviously spoofed IP's
#

$IPTABLES -t nat -A PREROUTING -i $INET_IFACE -s 192.168.0.0/16 -j
DROP
$IPTABLES -t nat -A PREROUTING -i $INET_IFACE -s 10.0.0.0/8 -j DROP
$IPTABLES -t nat -A PREROUTING -i $INET_IFACE -s 172.16.0.0/12 -j DROP

#
# INPUT chain
#
# Take care of bad TCP packets that we don't want
#

$IPTABLES -A INPUT -p tcp ! --syn -m state --state NEW -j LOG
--log-prefix "New not syn:"
$IPTABLES -A INPUT -p tcp ! --syn -m state --state NEW -j DROP"

#
# Rules for incoming packets from the internet
#

$IPTABLES -A INPUT -p ICMP -i $INET_IFACE -j icmp_packets
$IPTABLES -A INPUT -p TCP -i $INET_IFACE -j tcp_packets
$IPTABLES -A INPUT -p UDP -i $INET_IFACE -j udpincoming_packets

#
# Rules for special networks not part of the Internet
#

$IPTABLES -A INPUT -p ALL -i $LAN_IFACE -d $LAN_BCAST_ADRESS -j ACCEPT

$IPTABLES -A INPUT -p ALL -d $LOCALHOST_IP -j ACCEPT
$IPTABLES -A INPUT -p ALL -d $LAN_IP -j ACCEPT
$IPTABLES -A INPUT -p ALL -d $STATIC_IP -m state --state
ESTABLISHED,RELATED -j ACCEPT
$IPTABLES -A INPUT -m limit --limit 3/minute --limit-burst 3 -j LOG
--log-level DEBUG --log-prefix "IPT INPUT packet died: "

#
# OUTPUT chain
#

$IPTABLES -A OUTPUT -p tcp ! --syn -m state --state NEW -j LOG
--log-prefix "New not syn:"
$IPTABLES -A OUTPUT -p tcp ! --syn -m state --state NEW -j DROP"

$IPTABLES -A OUTPUT -p ALL -s $LOCALHOST_IP -j ACCEPT
$IPTABLES -A OUTPUT -p ALL -s $LAN_IP -j ACCEPT
$IPTABLES -A OUTPUT -p ALL -s $STATIC_IP -j ACCEPT
$IPTABLES -A OUTPUT -m limit --limit 3/minute --limit-burst 3 -j LOG
--log-level DEBUG --log-prefix "IPT OUTPUT packet died: "

例子 rc.DMZ.firewall <>

#!/bin/sh
#
# rc.DMZ.firewall - DMZ IP Firewall script for Linux 2.4.x
#
# Author: Oskar Andreasson
# (c) of BoingWorld.com, use at your own risk, do whatever you please
with
# it as long as you don't distribute this without due credits to
# BoingWorld.com
#

###########
# Configuration options, these will speed you up getting this script
to
# work with your own setup.

#
# your LAN's IP range and localhost IP. /24 means to only use the
first
24
# bits of the 32 bit IP adress. the same as netmask 255.255.255.0
#
# STATIC_IP is used by me to allow myself to do anything to myself,
might
# be a security risc but sometimes I want this. If you don't have a
static
# IP, I suggest not using this option at all for now but it's stil
# enabled per default and will add some really nifty security bugs for

all
# those who skips reading the documentation=)

LAN_IP_RANGE="192.168.0.0/24"
LAN_IP="192.168.0.2/32"
LAN_BCAST_ADRESS="192.168.0.255/32"
LAN_IFACE="eth1"

INET_IP="194.236.50.152/32"
INET_IFACE="eth0"

HTTP_IP="194.236.50.153/32"
DNS_IP="194.236.50.154/32"
DMZ_HTTP_IP="192.168.1.2/32"
DMZ_DNS_IP="192.168.1.3/32"
DMZ_IP="192.168.1.1/32"
DMZ_IFACE="eth2"

LO_IP="127.0.0.1/32"
LO_IFACE="127.0.0.1/32"

IPTABLES="/usr/local/sbin/iptables"

###########################################
#
# Load all required IPTables modules
#

#
# Needed to initially load modules
#

/sbin/depmod -a

#
# Adds some iptables targets like LOG, REJECT and MASQUARADE.
#

/sbin/modprobe ipt_LOG
/sbin/modprobe ipt_MASQUERADE

#
# Support for connection tracking of FTP and IRC.
#
#/sbin/modprobe ip_conntrack_ftp
#/sbin/modprobe ip_conntrack_irc

#CRITICAL: Enable IP forwarding since it is disabled by default.
#

echo "1" > /proc/sys/net/ipv4/ip_forward

#
# Dynamic IP users:
#
#echo "1" > /proc/sys/net/ipv4/ip_dynaddr

###########################################
#
# Chain Policies gets set up before any bad packets gets through
#

$IPTABLES -P INPUT DROP
$IPTABLES -P OUTPUT DROP
$IPTABLES -P FORWARD DROP

#
# the allowed chain for TCP connections, utilized in the FORWARD chain

#

$IPTABLES -N allowed
$IPTABLES -A allowed -p TCP --syn -j ACCEPT
$IPTABLES -A allowed -p TCP -m state --state ESTABLISHED,RELATED -j
ACCEPT
$IPTABLES -A allowed -p TCP -j DROP

#
# ICMP rules, utilized in the FORWARD chain
#

$IPTABLES -N icmp_packets
$IPTABLES -A icmp_packets -p ICMP -s 0/0 --icmp-type 0 -j ACCEPT
$IPTABLES -A icmp_packets -p ICMP -s 0/0 --icmp-type 3 -j ACCEPT
$IPTABLES -A icmp_packets -p ICMP -s 0/0 --icmp-type 5 -j ACCEPT
$IPTABLES -A icmp_packets -p ICMP -s 0/0 --icmp-type 11 -j ACCEPT

###########################################
# POSTROUTING chain in the nat table
#
# Enable IP SNAT for all internal networks trying to get out on the
Internet
#

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

###########################################
# PREROUTING chain in the nat table
#
# Do some checks for obviously spoofed IP's
#

$IPTABLES -t nat -A PREROUTING -i $INET_IFACE -s 192.168.0.0/16 -j
DROP
$IPTABLES -t nat -A PREROUTING -i $INET_IFACE -s 10.0.0.0/8 -j DROP
$IPTABLES -t nat -A PREROUTING -i $INET_IFACE -s 172.16.0.0/12 -j DROP

$IPTABLES -t nat -A PREROUTING -i $INET_IFACE -s $INET_IP -j DROP

#
# Enable IP Destination NAT for DMZ zone
#

$IPTABLES -t nat -A PREROUTING -p TCP -i $INET_IFACE -d $HTTP_IP --dport

80 -j DNAT --to-destination $DMZ_HTTP_IP
$IPTABLES -t nat -A PREROUTING -p TCP -i $INET_IFACE -d $DNS_IP
--dport
53 -j DNAT --to-destination $DMZ_DNS_IP
$IPTABLES -t nat -A PREROUTING -p UDP -i $INET_IFACE -d $DNS_IP
--dport
53 -j DNAT --to-destination $DMZ_DNS_IP

###########################################
#
# FORWARD chain
#
# Get rid of bad TCP packets
#

$IPTABLES -A FORWARD -p tcp ! --syn -m state --state NEW -j LOG
--log-prefix "New not syn:"
$IPTABLES -A FORWARD -p tcp ! --syn -m state --state NEW -j DROP

#
# DMZ section
#
# General rules
#

$IPTABLES -A FORWARD -i $DMZ_IFACE -o $INET_IFACE -j ACCEPT
$IPTABLES -A FORWARD -i $INET_IFACE -o $DMZ_IFACE -m state --state
ESTABLISHED,RELATED -j ACCEPTED

#
# HTTP server
#

$IPTABLES -A FORWARD -p TCP -i $INET_IFACE -o $DMZ_IFACE -d $DMZ_HTTP_IP

--dport 80 -j allowed
$IPTABLES -A FORWARD -p ICMP -i $INET_IFACE -o $DMZ_IFACE -d DMZ_HTTP_IP

-j icmp_packets

#
# DNS server
#

$IPTABLES -A FORWARD -p TCP -i $INET_IFACE -o $DMZ_IFACE -d
$DMZ_DNS_IP
--dport 53 -j allowed
$IPTABLES -A FORWARD -p UDP -i $INET_IFACE -o $DMZ_IFACE -d
$DMZ_DNS_IP
--dport 53 -j ACCEPT
$IPTABLES -A FORWARD -p ICMP -i $INET_IFACE -o $DMZ_IFACE -d $DMZ_DNS_IP

-j icmp_packets

#
# LAN section
#

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

#
# LOG all packets reaching here
#

$IPTABLES -A FORWARD -m limit --limit 3/minute --limit-burst 3 -j LOG
--log-level DEBUG --log-prefix "IPT FORWARD packet died: "

###########################################################
#
# Firewall rules
# Rules applying to the firewall box
#
#
# INPUT chain
#
# Get rid of bad packets
#

$IPTABLES -A FORWARD -p tcp ! --syn -m state --state NEW -j LOG
--log-prefix "New not syn:"
$IPTABLES -A FORWARD -p tcp ! --syn -m state --state NEW -j DROP

#
# Packets from the Internet to this box
#

$IPTABLES -A INPUT -p ICMP -i $INET_IFACE -j icmp_packets

#
# Packets from LAN, DMZ or LOCALHOST
#

# From DMZ Interface to DMZ firewall IP
$IPTABLES -A INPUT -p ALL -i $DMZ_IFACE -d $DMZ_IP -j ACCEPT

# From LAN Interface to LAN firewall IP
$IPTABLES -A INPUT -p ALL -i $LAN_IFACE -d $LAN_IP -j ACCEPT
$IPTABLES -A INPUT -p ALL -i $LAN_IFACE -d $LAN_BCAST_ADRESS -j ACCEPT

# From Localhost interface to Localhost IP
$IPTABLES -A INPUT -p ALL -i $LO_IFACE -d $LO_IP -j ACCEPT

# All established and related packets incoming from the internet to
the
firewall
$IPTABLES -A INPUT -p ALL -d $INET_IP -m state --state
ESTABLISHED,RELATED -j ACCEPT

# Logging rule
$IPTABLES -A INPUT -m limit --limit 3/minute --limit-burst 3 -j LOG
--log-level DEB

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最后更新: 2001年10月16日

--
                ═══════════════════﹃
                  过而结要情有结而过要情有
                  程不果的，些果不程的，些
                  。是，是重事；是，是重事
               ﹄═══════════════════

※ 来源:·哈工大紫丁香 bbs.hit.edu.cn·[FROM: 210.82.167.241]

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