分享一个不错的iptables脚本


    代码如下:
    复制代码
    代码如下:
    #!/bin/sh
    #
    modprobe ipt_MASQUERADE
    modprobe ip_conntrack_ftp
    modprobe ip_nat_ftp
    iptables -F
    iptables -t nat -F
    iptables -X
    iptables -t nat -X
    ###########################INPUT键###################################
    iptables -P INPUT DROP
    iptables -A INPUT -m state –state ESTABLISHED,RELATED -j ACCEPT
    iptables -A INPUT -p tcp -m multiport –dports 110,80,25 -j ACCEPT
    iptables -A INPUT -p tcp -s 192.168.0.0/24 –dport 139 -j ACCEPT
    #允许内网samba,smtp,pop3,连接
    iptables -A INPUT -i eth1 -p udp -m multiport –dports 53 -j ACCEPT
    #允许dns连接
    iptables -A INPUT -p tcp –dport 1723 -j ACCEPT
    iptables -A INPUT -p gre -j ACCEPT
    #允许外网vpn连接
    iptables -A INPUT -s 192.186.0.0/24 -p tcp -m state –state ESTABLISHED,RELATED -j ACCEPT
    iptables -A INPUT -i ppp0 -p tcp –syn -m connlimit –connlimit-above 15 -j DROP
    #为了防止DOS太多连接进来,那么可以允许最多15个初始连接,超过的丢弃
    iptables -A INPUT -s 192.186.0.0/24 -p tcp –syn -m connlimit –connlimit-above 15 -j DROP
    #为了防止DOS太多连接进来,那么可以允许最多15个初始连接,超过的丢弃
    iptables -A INPUT -p icmp -m limit –limit 3/s -j LOG –log-level INFO –log-prefix “ICMP packet IN: “
    iptables -A INPUT -p icmp -j DROP
    #禁止icmp通信-ping 不通
    iptables -t nat -A POSTROUTING -o ppp0 -s 192.168.0.0/24 -j MASQUERADE
    #内网转发
    iptables -N syn-flood
    iptables -A INPUT -p tcp –syn -j syn-flood
    iptables -I syn-flood -p tcp -m limit –limit 3/s –limit-burst 6 -j RETURN
    iptables -A syn-flood -j REJECT
    #防止SYN攻击 轻量
    #######################FORWARD链###########################
    iptables -P FORWARD DROP
    iptables -A FORWARD -p tcp -s 192.168.0.0/24 -m multiport –dports 80,110,21,25,1723 -j ACCEPT
    iptables -A FORWARD -p udp -s 192.168.0.0/24 –dport 53 -j ACCEPT
    iptables -A FORWARD -p gre -s 192.168.0.0/24 -j ACCEPT
    iptables -A FORWARD -p icmp -s 192.168.0.0/24 -j ACCEPT
    #允许 vpn客户走vpn网络连接外网
    iptables -A FORWARD -m state –state ESTABLISHED,RELATED -j ACCEPT
    iptables -I FORWARD -p udp –dport 53 -m string –string “tencent” -m time –timestart 8:15 –timestop 12:30 –days Mon,Tue,Wed,Thu,Fri,Sat -j DROP
    #星期一到星期六的8:00-12:30禁止qq通信
    iptables -I FORWARD -p udp –dport 53 -m string –string “TENCENT” -m time –timestart 8:15 –timestop 12:30 –days Mon,Tue,Wed,Thu,Fri,Sat -j DROP
    #星期一到星期六的8:00-12:30禁止qq通信
    iptables -I FORWARD -p udp –dport 53 -m string –string “tencent” -m time –timestart 13:30 –timestop 20:30 –days Mon,Tue,Wed,Thu,Fri,Sat -j DROP
    iptables -I FORWARD -p udp –dport 53 -m string –string “TENCENT” -m time –timestart 13:30 –timestop 20:30 –days Mon,Tue,Wed,Thu,Fri,Sat -j DROP
    #星期一到星期六的13:30-20:30禁止QQ通信
    iptables -I FORWARD -s 192.168.0.0/24 -m string –string “qq.com” -m time –timestart 8:15 –timestop 12:30 –days Mon,Tue,Wed,Thu,Fri,Sat -j DROP
    #星期一到星期六的8:00-12:30禁止qq网页
    iptables -I FORWARD -s 192.168.0.0/24 -m string –string “qq.com” -m time –timestart 13:00 –timestop 20:30 –days Mon,Tue,Wed,Thu,Fri,Sat -j DROP
    #星期一到星期六的13:30-20:30禁止QQ网页
    iptables -I FORWARD -s 192.168.0.0/24 -m string –string “ay2000.net” -j DROP
    iptables -I FORWARD -d 192.168.0.0/24 -m string –string “宽频影院” -j DROP
    iptables -I FORWARD -s 192.168.0.0/24 -m string –string “ZZ” -j DROP
    iptables -I FORWARD -p tcp –sport 80 -m string –string “广告” -j DROP
    #禁止ay2000.net,宽频影院,ZZ,广告网页连接 !但中文 不是很理想
    iptables -A FORWARD -m ipp2p –edk –kazaa –bit -j DROP
    iptables -A FORWARD -p tcp -m ipp2p –ares -j DROP
    iptables -A FORWARD -p udp -m ipp2p –kazaa -j DROP
    #禁止BT连接
    iptables -A FORWARD -p tcp –syn –dport 80 -m connlimit –connlimit-above 15 –connlimit-mask 24
    #######################################################################
    sysctl -w net.ipv4.ip_forward=1 &>/dev/null
    #打开转发
    #######################################################################
    sysctl -w net.ipv4.tcp_syncookies=1 &>/dev/null
    #打开 syncookie (轻量级预防 DOS 攻击)
    sysctl -w net.ipv4.netfilter.ip_conntrack_tcp_timeout_established=3800 &>/dev/null
    #设置默认 TCP 连接痴呆时长为 3800 秒(此选项可以大大降低连接数)
    sysctl -w net.ipv4.ip_conntrack_max=300000 &>/dev/null
    #设置支持最大连接树为 30W(这个根据你的内存和 iptables 版本来,每个 connection 需要 300 多个字节)
    #######################################################################
    iptables -I INPUT -s 192.168.0.50 -j ACCEPT
    iptables -I FORWARD -s 192.168.0.50 -j ACCEPT
    #192.168.0.50是我的机子,全部放行!
    ############################完#########################################