#!/bin/bash
#文件名: Blacklist_SSH.sh
#功能: 将使用暴力破解 SSH 服务者加入到 SSH 黑名单
#作者: shuhui

DEFINE="5"
grep 'sshd' /var/log/secure|awk '/Failed/{print $(NF-3)}'|sort|uniq -c|awk '{print $2"="$1;}' > /tmp/black.txt

for i in $(cat /tmp/black.txt)
do
    IP=$(echo $i |awk -F= '{print $1}')
    NUM=$(echo $i|awk -F= '{print $2}')
    
    if [ $NUM -gt $DEFINE ]
    then
        grep $IP /etc/hosts.deny > /dev/null || echo "sshd:$IP" >> /etc/hosts.deny
    fi
done
