black_list

#! /bin/bash

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

DEFINE="5"

for i in `cat /root/black/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

if [ $? -gt 0 ]; then
echo "sshd:$IP" >> /etc/hosts.deny
fi
fi
done