#!/bin/bash
#Author:ZhangGe
#Desc:Auto Deny Black_IP Script.
#Date:2014-11-05
#取得参数$1为并发阈值，若留空则默认允许单IP最大50并发(实际测试发现，2M带宽，十来个并发服务器就已经无法访问了！)
if [[ –z $1 ]];then
num=50
else
num=$1
#巧妙的进入到脚本工作目录
cd $(cd $(dirname $BASH_SOURCE) && pwd)
#请求检查、判断及拉黑主功能函数
function check(){
iplist=`netstat –an |grep ^tcp.*:80|egrep –v ‘LISTEN|127.0.0.1’|awk –F“[ ]+|[:]” ‘{print $6}’|sort|uniq –c|sort –rn|awk –v str=$num ‘{if ($1>str){print $2}}’`
if [[ ! –z $iplist ]];
then
>./black_ip.txt
for black_ip in $iplist
do
#白名单过滤中已取消IP段的判断功能，可根据需要自行修改以下代码(请参考前天写的脚本)
#exclude_ip=`echo $black_ip | awk -F”.” ‘{print $1″.”$2″.”$3}’`
#grep -q $exclude_ip ./white_ip.txt
grep –q $black_ip ./white_ip.txt
if [[ $? –eq 0 ]];then
echo “$black_ip (white_ip)” >>./black_ip.txt
else
echo $black_ip >>./black_ip.txt
iptables –nL | grep $black_ip ||(iptables –I INPUT –s $black_ip –j DROP & echo “$black_ip `date +%Y-%m-%H:%M:%S`”>>./deny.log & echo 1 >./sendmail)
fi
done
#存在并发超过阈值的单IP就发送邮件
if [[ `cat ./sendmail` == 1 ]];then sendmsg;fi
fi
#发邮件函数
function sendmsg(){
netstat –nutlp | grep “sendmail” >/dev/null 2>&1 || /etc/init.d/sendmail start >/dev/null 2>&1
echo –e “From: 发邮件地址@qq.com\nTo:收邮件地址@qq.com\nSubject:Someone Attacking your system!!\nIts Ip is” >./message
cat ./black_ip.txt >>./message
/usr/sbin/sendmail –f 发邮件地址@qq.com –t 收邮件地址@qq.com –i <./message
>./sendmail
#间隔10s无限循环检查函数
while true
check
#每隔10s检查一次，时间可根据需要自定义
sleep 10
done
原文链接：https://www.cnblogs.com/bky185392793/p/7881005.html
原创文章，作者：优速盾-小U，如若转载，请注明出处：https://www.cdnb.net/bbs/archives/20922
