shell脚本实现被远程时5次输错密码而直接禁止访问

#!/bin/bash
cat /var/log/secure | awk '/Failed/{print $11}' >> ip.txt
for i in

cat ip.txt

do
x=

awk '{ip[$1]++} END{for (i in ip){print i,ip[i]}}' /ip.txt | awk '{print $2}'

if [ $x -gt 5 ];then
firewall-cmd --zone=drop --add-source=$i
fi
done