SYN攻击TIME_WAIT防御。
1 #! /bin/bash 2 3 /bin/netstat -anput | grep TIME_WAIT >time_wait.txt 4 /bin/cat time_wait.txt |awk '{print $5}' |awk -F '[:]' '{print $1}' |sort|uniq -c |awk '{print $2"="$1;}' >wait_num.txt 5 6 DEFINE="300" 7 for i in `/bin/cat /root/wait_num.txt` 8 do 9 IP=`echo $i |awk -F= '{print $1}'` 10 NUM=`echo $i|awk -F= '{print $2}'` 11 if [ $NUM -gt $DEFINE ];then 12 grep $IP /etc/sysconfig/iptables > /dev/null 13 if [ $? -gt 0 ];then 14 /sbin/iptables -I INPUT -s $IP -j DROP 15 echo "`date` $IP($NUM) ----将该IP加入到防火墙中。。。" >> /var/log/scanner.log 16 fi 17 fi 18 done