update ssh banlist on centos

update_ssh_banlist.py

import subprocess

bashCommand = '''
last | awk '{ print $1"|"$3 }'
'''
process = subprocess.Popen(bashCommand,shell=True,stdout=subprocess.PIPE,stderr=subprocess.STDOUT)
output, error = process.communicate()
lines=output.split('\n')


white_list=set()
for l in lines:
    if not l:
        continue
    user,ip=l.split('|')
    if not user or not ip:
        continue
    if ip.count('.')==3:
        white_list.add(ip)
print(white_list)

bashCommand = '''
lastb | awk '{ print $1"|"$3 }'
'''
process = subprocess.Popen(bashCommand,shell=True,stdout=subprocess.PIPE,stderr=subprocess.STDOUT)
output, error = process.communicate()
lines=output.split('\n')

white_users=['luotao']
ban_list=set()
for l in lines:
    if not l:
        continue
    user,ip=l.split('|')
    if not user or not ip or user in white_users:
        continue
    if ip.count('.')==3 and ip not in white_list:
        ban_list.add(ip)

with open('/etc/hosts.deny', 'w+') as f:
    for ip in ban_list:
        f.write('sshd: %s\n'%ip)