标题:Linux的iptables常用配置范例(1) 出处:沧海一粟 时间:Sat, 02 Apr 2011 01:02:17 +0000 作者:jed 地址:http://www.dzhope.com/post/790/ 内容: 以下是来自 http://wiki.ubuntu.org.cn/IptablesHowTo 上的配置说明 可以通过/sbin/iptables -F清除所有规则来暂时停止防火墙: (警告:这只适合在没有配置防火墙的环境中,如果已经配置过默认规则为deny的环境,此步骤将使系统的所有网络访问中断) 如果想清空的话,先执行 /sbin/iptables -P INPUT ACCEPT 然后执行 /sbin/iptables -F 通过iptables -L 看到如下信息 Chain INPUT (policy DROP 0 packets, 0 bytes) (注意 是DROP) 执行/sbin/iptables -F就肯定立马断开连接 当执行了 /sbin/iptables -P INPUT ACCEPT 再次通过iptables -L看信息的话就是 Chain FORWARD (policy ACCEPT 0 packets, 0 bytes) 所以现在是可以安全使用 /sbin/iptables -F了 —————————————————————— 常用的IPTABLES规则如下: 只能收发邮件,别的都关闭 iptables -I Filter -m mac –mac-source 00:0F:EA:25:51:37 -j DROP iptables -I Filter -m mac –mac-source 00:0F:EA:25:51:37 -p udp --dport 53 -j ACCEPT iptables -I Filter -m mac –mac-source 00:0F:EA:25:51:37 -p tcp --dport 25 -j ACCEPT iptables -I Filter -m mac –mac-source 00:0F:EA:25:51:37 -p tcp --dport 110 -j ACCEPT IPSEC NAT 策略 iptables -I PFWanPriv -d 192.168.100.2 -j ACCEPT iptables -t nat -A PREROUTING -p tcp --dport 80 -d $INTERNET_ADDR -j DNAT –to-destination 192.168.100.2:80 iptables -t nat -A PREROUTING -p tcp --dport 1723 -d $INTERNET_ADDR -j DNAT –to-destination 192.168.100.2:1723 iptables -t nat -A PREROUTING -p udp --dport 1723 -d $INTERNET_ADDR -j DNAT –to-destination 192.168.100.2:1723 iptables -t nat -A PREROUTING -p udp --dport 500 -d $INTERNET_ADDR -j DNAT –to-destination 192.168.100.2:500 iptables -t nat -A PREROUTING -p udp --dport 4500 -d $INTERNET_ADDR -j DNAT –to-destination 192.168.100.2:4500 FTP服务器的NAT iptables -I PFWanPriv -p tcp --dport 21 -d 192.168.100.200 -j ACCEPT iptables -t nat -A PREROUTING -p tcp --dport 21 -d $INTERNET_ADDR -j DNAT –to-destination 192.168.100.200:21 只允许访问指定网址 iptables -A Filter -p udp --dport 53 -j ACCEPT iptables -A Filter -p tcp --dport 53 -j ACCEPT iptables -A Filter -d www.3322.org -j ACCEPT iptables -A Filter -d img.cn99.com -j ACCEPT iptables -A Filter -j DROP 开放一个IP的一些端口,其它都封闭 iptables -A Filter -p tcp --dport 80 -s 192.168.100.200 -d www.pconline.com.cn -j ACCEPT iptables -A Filter -p tcp --dport 25 -s 192.168.100.200 -j ACCEPT iptables -A Filter -p tcp --dport 109 -s 192.168.100.200 -j ACCEPT iptables -A Filter -p tcp --dport 110 -s 192.168.100.200 -j ACCEPT iptables -A Filter -p tcp --dport 53 -j ACCEPT iptables -A Filter -p udp --dport 53 -j ACCEPT iptables -A Filter -j DROP 多个端口 iptables -A Filter -p tcp -m multiport –destination-port 22,53,80,110 -s 192.168.20.3 -j REJECT 连续端口 iptables -A Filter -p tcp -m multiport –source-port 22,53,80,110 -s 192.168.20.3 -j REJECT iptables -A Filter -p tcp –source-port 2:80 -s 192.168.20.3 -j REJECT 指定时间上网 iptables -A Filter -s 10.10.10.253 -m time –timestart 6:00 –timestop 11:00 –days Mon,Tue,Wed,Thu,Fri,Sat,Sun -j DROP iptables -A Filter -m time –timestart 12:00 –timestop 13:00 –days Mon,Tue,Wed,Thu,Fri,Sat,Sun -j ACCEPT iptables -A Filter -m time –timestart 17:30 –timestop 8:30 –days Mon,Tue,Wed,Thu,Fri,Sat,Sun -j ACCEPT 禁止多个端口服务 iptables -A Filter -m multiport -p tcp --dport 21,23,80 -j ACCEPT 将WAN 口NAT到PC iptables -t nat -A PREROUTING -i $INTERNET_IF -d $INTERNET_ADDR -j DNAT –to-destination 192.168.0.1 将WAN口8000端口NAT到192。168。100。200的80端口 iptables -t nat -A PREROUTING -p tcp --dport 8000 -d $INTERNET_ADDR -j DNAT –to-destination 192.168.100.200:80 MAIL服务器要转的端口 iptables -t nat -A PREROUTING -p tcp --dport 110 -d $INTERNET_ADDR -j DNAT –to-destination 192.168.100.200:110 iptables -t nat -A PREROUTING -p tcp --dport 25 -d $INTERNET_ADDR -j DNAT –to-destination 192.168.100.200:25 只允许PING 202。96。134。133,别的服务都禁止 iptables -A Filter -p icmp -s 192.168.100.200 -d 202.96.134.133 -j ACCEPT iptables -A Filter -j DROP 禁用BT配置 iptables –A Filter –p tcp --dport 6000:20000 –j DROP 禁用QQ防火墙配置 iptables -A Filter -p udp --dport ! 53 -j DROP iptables -A Filter -d 218.17.209.0/24 -j DROP iptables -A Filter -d 218.18.95.0/24 -j DROP iptables -A Filter -d 219.133.40.177 -j DROP 基于MAC,只能收发邮件,其它都拒绝 iptables -I Filter -m mac –mac-source 00:0A:EB:97:79:A1 -j DROP iptables -I Filter -m mac –mac-source 00:0A:EB:97:79:A1 -p tcp --dport 25 -j ACCEPT iptables -I Filter -m mac –mac-source 00:0A:EB:97:79:A1 -p tcp --dport 110 -j ACCEPT 禁用MSN配置 iptables -A Filter -p udp --dport 9 -j DROP iptables -A Filter -p tcp --dport 1863 -j DROP iptables -A Filter -p tcp --dport 80 -d 207.68.178.238 -j DROP iptables -A Filter -p tcp --dport 80 -d 207.46.110.0/24 -j DROP 只允许PING 202。96。134。133 其它公网IP都不许PING iptables -A Filter -p icmp -s 192.168.100.200 -d 202.96.134.133 -j ACCEPT iptables -A Filter -p icmp -j DROP 禁止某个MAC地址访问internet: iptables -I Filter -m mac –mac-source 00:20:18:8F:72:F8 -j DROP 禁止某个IP地址的PING: iptables –A Filter –p icmp –s 192.168.0.1 –j DROP 禁止某个IP地址服务: iptables –A Filter -p tcp -s 192.168.0.1 --dport 80 -j DROP iptables –A Filter -p udp -s 192.168.0.1 --dport 53 -j DROP 只允许某些服务,其他都拒绝(2条规则) iptables -A Filter -p tcp -s 192.168.0.1 --dport 1000 -j ACCEPT iptables -A Filter -j DROP 禁止某个IP地址的某个端口服务 iptables -A Filter -p tcp -s 10.10.10.253 --dport 80 -j ACCEPT iptables -A Filter -p tcp -s 10.10.10.253 --dport 80 -j DROP 禁止某个MAC地址的某个端口服务 iptables -I Filter -p tcp -m mac –mac-source 00:20:18:8F:72:F8 --dport 80 -j DROP 禁止某个MAC地址访问internet: iptables -I Filter -m mac –mac-source 00:11:22:33:44:55 -j DROP 禁止某个IP地址的PING: iptables –A Filter –p icmp –s 192.168.0.1 –j DROP ———————————————————————————————— IPFW 或 Netfilter 的封包流向,local process 不会经过 FORWARD Chain, 因此 lo 只在 INPUT 及 OUTPUT 二个 chain 作用。 样例1: #!/bin/sh # # 静态安全防火墙脚本 # # created by yejr,2007-03-20 # # #定义信任IP列表 #内部ip子网 MY_IP_LIST_1=192.168.8.0/24 #外部ip子网 MY_IP_LIST_2=1.2.3.0/24 #所有 ALL_IP=0/0 #北京ADSL动态IP列表 BJADSL_IP_LIST=221.218.0.0/16 #定义端口列表 #涉及ftp端口 FTP_PORT_1=20 FTP_PORT_RANGE=”1023:65535″ FTP_PORT_2=21 #dns端口 DNS_PORT=53 #httpd端口 HTTP_PORT=80 #ssh 端口 SSH_PORT=4321 IPT=”/sbin/iptables” # 内网 LC_IFACE=”eth1″ LC_ADDR=”192.168.8.2″ # 公网 INET_IFACE=”eth0″ INET_ADDR=”1.2.3.4″ # 本机 LO_IFACE=”lo” LO_ADDR=127.0.0.1 # 定义接受请求速率限制 MAX_NUM_PACKS=1024 # 核心模块 /sbin/modprobe ip_tables # ftp模块 /sbin/modprobe ip_nat_ftp # 限速模块 /sbin/modprobe ip_conntrack # 重新设置防火墙到默认状态 $IPT -P INPUT ACCEPT $IPT -P FORWARD ACCEPT #$IPT -P OUTPUT ACCEPT $IPT -F $IPT -X # 先拒绝所有请求 $IPT -P INPUT DROP #$IPT -P OUTPUT DROP $IPT -P FORWARD DROP ########################################## # 设定一些内核参数 ########################################## #启动 SYN 泛洪保护 echo ”1″ > /proc/sys/net/ipv4/tcp_syncookies #启用反向路径源认证,防止欺骗 echo ”1″ > /proc/sys/net/ipv4/conf/all/rp_filter #关闭 icom echo 广播包请求 echo ”1″ > /proc/sys/net/ipv4/icmp_echo_ignore_broadcasts #拒绝源路由包 echo ”0″ > /proc/sys/net/ipv4/conf/all/accept_source_route #仅仅接收发给默认网关列表中网关的ICMP重定向消息 echo ”1″ > /proc/sys/net/ipv4/conf/all/secure_redirects #记录来自非法ip的请求 echo ”1″ > /proc/sys/net/ipv4/conf/all/log_martians ########################################## # 建立规则 ########################################## # 无效请求包规则 $IPT -N bad_packets # 另一个恶意 TCP 包规则 $IPT -N bad_tcp_packets # ICMP规则(进/出) $IPT -N icmp_packets # 来自公网的UDP请求规则 $IPT -N inet_udp_inbound # 从本机发往公网的UDP请求规则,默认全部允许 $IPT -N udp_outbound # 来自公网的 TCP 请求规则 $IPT -N inet_tcp_inbound # 从本机发往公网的 TCP 请求规则,默认全部允许 $IPT -N tcp_outbound ########################################## # 恶意请求规则 ########################################## # 立刻断掉非法的包并且记录 $IPT -A bad_packets -p ALL -m state --state INVALID -j LOG –log-prefix ”IPTABLES_INVALID_PACKET:” $IPT -A bad_packets -p ALL -m state --state INVALID -j DROP # 再次检查 TCP 包是否还有问题 $IPT -A bad_packets -p tcp -j bad_tcp_packets # 都正确了,返回 $IPT -A bad_packets -p ALL -j RETURN ########################################## # 恶意 TCP 请求 ########################################## # # 所有的 TCP 请求都必须经过以下规则过滤. 任何新请求都 # 必须以一个 sync 包开始. # 如果不是这样的话,很可能表示这是一个扫描动作,这些有 # NEW 状态的包会被丢弃 # $IPT -A bad_tcp_packets -p tcp ! –syn -m state --state NEW -j LOG –log-prefix ”IPTABLES_NEW_NOT_SYN:” $IPT -A bad_tcp_packets -p tcp ! –syn -m state --state NEW -j DROP $IPT -A bad_tcp_packets -p tcp –tcp-flags ALL NONE -j LOG –log-prefix ”IPTABLES_STEALTH_SCAN:” $IPT -A bad_tcp_packets -p tcp –tcp-flags ALL NONE -j DROP $IPT -A bad_tcp_packets -p tcp –tcp-flags ALL ALL -j LOG –log-prefix ”IPTABLES_STEALTH_SCAN:” $IPT -A bad_tcp_packets -p tcp –tcp-flags ALL ALL -j DROP $IPT -A bad_tcp_packets -p tcp –tcp-flags ALL FIN,URG,PSH -j LOG –log-prefix ”IPTABLES_STEALTH_SCAN:” $IPT -A bad_tcp_packets -p tcp –tcp-flags ALL FIN,URG,PSH -j DROP $IPT -A bad_tcp_packets -p tcp –tcp-flags ALL SYN,RST,ACK,FIN,URG -j LOG –log-prefix ”IPTABLES_STEALTH SCAN:” $IPT -A bad_tcp_packets -p tcp –tcp-flags ALL SYN,RST,ACK,FIN,URG -j DROP $IPT -A bad_tcp_packets -p tcp –tcp-flags SYN,RST SYN,RST -j LOG –log-prefix “IPTABLES_STEALTH SCAN:” $IPT -A bad_tcp_packets -p tcp –tcp-flags SYN,RST SYN,RST -j DROP $IPT -A bad_tcp_packets -p tcp –tcp-flags SYN,FIN SYN,FIN -j LOG –log-prefix “IPTABLES_STEALTH SCAN:” $IPT -A bad_tcp_packets -p tcp –tcp-flags SYN,FIN SYN,FIN -j DROP # 都没问题了,返回 $IPT -A bad_tcp_packets -p tcp -j RETURN ########################################## # ICMP 包规则 ########################################## # # ICMP 包必须封装在一个2层的帧中,因此它们不会有碎片. # 带有碎片的 ICMP 包通常被 # 标记为恶意攻击 # $IPT -A icmp_packets –fragment -p ICMP -j LOG –log-prefix ”IPTABLES_ICMP Fragment:” $IPT -A icmp_packets –fragment -p ICMP -j DROP # # 默认地,所有丢弃的 ICMP 包都不记录日志. ”冲击波” # 以及 ”蠕虫” 会导致系统发起大量 # ping 请求. 如果想要记录 icmp log 就不要把本行注释掉 # # 允许自有服务器ip及北京地区adsl ip进行 PING $IPT -A icmp_packets -p ICMP -s $MY_IP_LIST_2 -j ACCEPT $IPT -A icmp_packets -p ICMP -s $BJADSL_IP_LIST -j ACCEPT # 拒掉其他 PING $IPT -A icmp_packets -p ICMP -s 0/0 –icmp-type 8 -j DROP # 接受超时 icmp 包 $IPT -A icmp_packets -p ICMP -s 0/0 –icmp-type 11 -j ACCEPT ########################################## # TCP & UDP 包规则 ########################################## ########################################## # 来自公网的 UDP 请求 ########################################## #$IPT -A inet_udp_inbound -p UDP -s $MY_IP_LIST_2 --dport $DNS_PORT -j ACCEPT # 都没问题了,返回 $IPT -A inet_udp_inbound -p UDP -j RETURN ########################################## # 发往公网的 UDP 请求 ########################################## # 都没问题了,返回 $IPT -A udp_outbound -p UDP -s 0/0 -j ACCEPT ########################################## # 来自公网的 TCP 请求 ########################################## # sshd 只对 北京ADSL IP段开放 $IPT -A inet_tcp_inbound -p TCP -s $BJADSL_IP_LIST --dport $SSH_PORT -j ACCEPT # 允许自有服务器 IP 的 FTP 端口请求 # FTP Data fix $IPT -A inet_tcp_inbound -p TCP -s $MY_IP_LIST_2 –sport $FTP_PORT_1 --dport $FTP_PORT_RANGE ! –syn -m state --state RELATED -j ACCEPT $IPT -A inet_tcp_inbound -p TCP -s $MY_IP_LIST_2 -m state --state ESTABLISHED -j ACCEPT $IPT -A inet_tcp_inbound -p UDP -s $MY_IP_LIST_2 --dport $FTP_PORT_RANGE -j ACCEPT $IPT -A inet_tcp_inbound -p TCP -s $MY_IP_LIST_2 --dport $FTP_PORT_1 ! –syn -j ACCEPT $IPT -A inet_tcp_inbound -p TCP -s $MY_IP_LIST_2 --dport $FTP_PORT_2 -j ACCEPT #允许所有ip访问 http 服务 $IPT -A inet_tcp_inbound -p TCP -s $ALL_IP --dport $HTTP_PORT -j ACCEPT # 都没问题了,返回 $IPT -A inet_tcp_inbound -p TCP -j RETURN ########################################## # 发往公网的 TCP 请求 ########################################## # 都没问题了,返回 $IPT -A tcp_outbound -p TCP -s 0/0 -j ACCEPT ########################################## # 其他收到的请求 ########################################## # 允许本机及本子网间的任何通信 $IPT -A INPUT -p ALL -i $LO_IFACE -j ACCEPT $IPT -A INPUT -p ALL -d $LC_ADDR -j ACCEPT # 来自信任ip的任何请求都接受 $IPT -A INPUT -p ALL -s $MY_IP_LIST_1 -j ACCEPT $IPT -A INPUT -p ALL -s $MY_IP_LIST_2 -j ACCEPT # 丢弃任何错误包 $IPT -A INPUT -p ALL -j bad_packets # 拒掉 DOCSIS 请求 $IPT -A INPUT -p ALL -d 224.0.0.1 -j REJECT # 接受 Established 连接 $IPT -A INPUT -p ALL -i $INET_IFACE -m state --state ESTABLISHED,RELATED -j ACCEPT # 定义上面的几条路由规则 $IPT -A INPUT -p TCP -d $INET_ADDR -j inet_tcp_inbound $IPT -A INPUT -p UDP -d $INET_ADDR -j inet_udp_inbound $IPT -A INPUT -p ICMP -d $INET_ADDR -j icmp_packets # 丢弃且不记录广播包 $IPT -A INPUT -m pkttype –pkt-type broadcast -j REJECT # 记录其他未匹配到的包 $IPT -A INPUT -m limit –limit $MAX_NUM_PACKS/minute –limit-burst $MAX_NUM_PACKS -j LOG –log-prefix “IPTABLES_MISS_MATCH_INPUT:” ########################################## # 其他发出的请求 ########################################## # 无论如何都丢弃错误的 ICMP 包,防止溢出 $IPT -A OUTPUT -m state -p icmp --state INVALID -j REJECT # 允许对外的任何请求 $IPT -A OUTPUT -p ALL -s $ALL_IP -j ACCEPT # 记录其他未匹配到的包 $IPT -A OUTPUT -m limit –limit $MAX_NUM_PACKS/minute –limit-burst $MAX_NUM_PACKS -j LOG –log-prefix “IPTABLES_MISS_MATCH_OUTPUT: ” —————————————— 我的样例: —————————————— #!/bin/sh # # rc.firewall - Initial SIMPLE IP Firewall script for Linux 2.6.x and iptables # # Copyright (C) 2006 Oskar Andreasson # # 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=”1.2.3.4″ INET_IP_1=”1.2.3.5″ INET_IFACE=”eth0″ INET_BROADCAST=”1.2.3.127″ # # 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=”192.168.0.33″ LAN_IP_RANGE=”192.168.0.0/24″ LAN_IFACE=”eth1″ # # 1.3 DMZ Configuration. # # # 1.4 Localhost Configuration. # LO_IFACE=”lo” LO_IP=”127.0.0.1″ # # 1.5 IPTables Configuration. # IPTABLES=”/sbin/iptables” # # 1.6 Other Configuration. # ########################################################################### # # 2. Module loading. # # # Needed to initially load modules /sbin/depmod -a # # 2.1 Required modules # /sbin/modprobe ip_tables /sbin/modprobe ip_conntrack /sbin/modprobe iptable_filter #/sbin/modprobe iptable_mangle #/sbin/modprobe iptable_nat /sbin/modprobe ipt_LOG /sbin/modprobe ipt_limit /sbin/modprobe ipt_state # # 2.2 Non-Required modules # #/sbin/modprobe ipt_owner #/sbin/modprobe ipt_REJECT #/sbin/modprobe ipt_MASQUERADE #/sbin/modprobe ip_conntrack_ftp #/sbin/modprobe ip_conntrack_irc #/sbin/modprobe ip_nat_ftp #/sbin/modprobe ip_nat_irc ########################################################################### # # 3. /proc set up. # # # 3.1 Required proc configuration # #echo ”1″ > /proc/sys/net/ipv4/ip_forward echo ”1″ > /proc/sys/net/ipv4/tcp_syncookies echo ”1″ > /proc/sys/net/ipv4/icmp_ignore_bogus_error_responses # 3.2 Non-Required proc configuration # #echo ”1″ > /proc/sys/net/ipv4/conf/all/rp_filter #echo ”1″ > /proc/sys/net/ipv4/conf/all/proxy_arp #echo ”1″ > /proc/sys/net/ipv4/ip_dynaddr #echo ”1″ > /proc/sys/net/ipv4/tcp_syncookies #启用反向路径源认证,防止欺骗 #echo ”1″ > /proc/sys/net/ipv4/conf/all/rp_filter #关闭 icom echo 广播包请求 #echo ”1″ > /proc/sys/net/ipv4/icmp_echo_ignore_broadcasts #拒绝源路由包 #echo ”0″ > /proc/sys/net/ipv4/conf/all/accept_source_route #仅仅接收发给默认网关列表中网关的ICMP重定向消息 #echo ”1″ > /proc/sys/net/ipv4/conf/all/secure_redirects #记录来自非法ip的请求 #echo ”1″ > /proc/sys/net/ipv4/conf/all/log_martians ########################################################################### # # 4. rules set up. # ###### # 4.1 Filter table # # # 4.1.1 Set policies # $IPTABLES -F $IPTABLES -X $IPTABLES -F -t mangle $IPTABLES -t mangle -X $IPTABLES -F -t nat $IPTABLES -t nat -X $IPTABLES -P INPUT DROP $IPTABLES -P OUTPUT DROP $IPTABLES -P FORWARD DROP # # 4.1.2 Create userspecified chains # # # Create chain for bad tcp packets # $IPTABLES -N bad_tcp_packets # # Create separate chains for ICMP, TCP and UDP to traverse # $IPTABLES -N allowed $IPTABLES -N tcp_packets $IPTABLES -N udp_packets $IPTABLES -N icmp_packets # # 4.1.3 Create content in userspecified chains # # # bad_tcp_packets chain # $IPTABLES -A bad_tcp_packets -p tcp –tcp-flags SYN,ACK SYN,ACK -m state --state NEW -j REJECT –reject-with tcp-reset $IPTABLES -A bad_tcp_packets -p tcp ! –syn -m state --state NEW -j LOG –log-prefix ”New not syn:” #$IPTABLES -A bad_tcp_packets -p tcp ! –syn -m state --state NEW -j DROP #$IPT -A bad_packets -p ALL -m state --state INVALID -j LOG –log-prefix ”IPTABLES_INVALID_PACKET:” #$IPT -A bad_packets -p ALL -m state --state INVALID -j DROP # # allowed chain # $IPTABLES -A allowed -p TCP –syn -j ACCEPT $IPTABLES -A allowed -p TCP -m state --state ESTABLISHED,RELATED -j ACCEPT $IPTABLES -A allowed -p TCP -j DROP # # TCP rules # #$IPTABLES -A tcp_packets -p TCP -s 0/0 --dport 21 -j allowed $IPTABLES -A tcp_packets -p TCP -s 0/0 --dport 30000 -j allowed #$IPTABLES -A tcp_packets -p TCP -s 0/0 --dport 22 -j allowed $IPTABLES -A tcp_packets -p TCP -s 0/0 --dport 80 -j allowed $IPTABLES -A tcp_packets -p TCP -s 0/0 --dport 10050 -j allowed $IPTABLES -A tcp_packets -p TCP -s 0/0 --dport 10051 -j allowed $IPTABLES -A tcp_packets -p TCP -s 0/0 -d $INET_IP_1 --dport 25 -j allowed $IPTABLES -A tcp_packets -p TCP -s 0/0 -d $INET_IP_1 --dport 110 -j allowed #$IPTABLES -A tcp_packets -p TCP -s 0/0 --dport 2009 -j allowed # # UDP ports # #$IPTABLES -A udp_packets -p UDP -s 0/0 –destination-port 53 -j ACCEPT #$IPTABLES -A udp_packets -p UDP -s 0/0 –destination-port 123 -j ACCEPT #$IPTABLES -A udp_packets -p UDP -s 0/0 –destination-port 2074 -j ACCEPT #$IPTABLES -A udp_packets -p UDP -s 0/0 –destination-port 4000 -j ACCEPT # # In Microsoft Networks you will be swamped by broadcasts. These lines # will prevent them from showing up in the logs. # $IPTABLES -A udp_packets -p UDP -i $INET_IFACE -d $INET_BROADCAST –destination-port 135:139 -j DROP # # If we get DHCP requests from the Outside of our network, our logs will # be swamped as well. This rule will block them from getting logged. # $IPTABLES -A udp_packets -p UDP -i $INET_IFACE -d 255.255.255.255 –destination-port 67:68 -j DROP # # ICMP rules # $IPTABLES -A icmp_packets -p ICMP -s 0/0 –icmp-type 8 -j ACCEPT $IPTABLES -A icmp_packets -p ICMP -s 0/0 –icmp-type 11 -j ACCEPT # # 4.1.4 INPUT chain # # # Bad TCP packets we don’t want. # $IPTABLES -A INPUT -p tcp -j bad_tcp_packets # # Special rule for DHCP requests from LAN, which are not caught properly # otherwise. # #$IPTABLES -A INPUT -p UDP -i $LAN_IFACE --dport 67 –sport 68 -j ACCEPT # # Rules for incoming packets from the internet. # $IPTABLES -A INPUT -p ALL -d $INET_IP -m state --state ESTABLISHED,RELATED -j ACCEPT $IPTABLES -A INPUT -p ALL -d $INET_IP_1 -m state --state ESTABLISHED,RELATED -j ACCEPT $IPTABLES -A INPUT -p TCP -i $INET_IFACE -j tcp_packets $IPTABLES -A INPUT -p UDP -i $INET_IFACE -j udp_packets $IPTABLES -A INPUT -p ICMP -i $INET_IFACE -j icmp_packets # Rules for special networks not part of the Internet # $IPTABLES -A INPUT -p ALL -i $LAN_IFACE -s $LAN_IP_RANGE -j ACCEPT $IPTABLES -A INPUT -p ALL -i $LO_IFACE -s $LO_IP -j ACCEPT $IPTABLES -A INPUT -p ALL -i $LO_IFACE -s $LAN_IP -j ACCEPT $IPTABLES -A INPUT -p ALL -i $LO_IFACE -s $INET_IP -j ACCEPT $IPTABLES -A INPUT -p ALL -i $LO_IFACE -s $INET_IP_1 -j ACCEPT # # If you have a Microsoft Network on the outside of your firewall, you may # also get flooded by Multicasts. We drop them so we do not get flooded by # logs # $IPTABLES -A INPUT -i $INET_IFACE -d 224.0.0.0/8 -j DROP # # Log weird packets that don’t match the above. # $IPTABLES -A INPUT -m limit –limit 3/minute –limit-burst 3 -j LOG –log-level DEBUG –log-prefix ”IPT INPUT packet died: ” # # 4.1.5 FORWARD chain # # # Bad TCP packets we don’t want # #$IPTABLES -A FORWARD -p tcp -j bad_tcp_packets # # 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 $IPTABLES -A OUTPUT -p ALL -s $INET_IP_1 -j ACCEPT # # Log weird packets that don’t match the above. # #$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 # ------------------------------------ Generated by Bo-blog 2.1.1 Release