#!/usr/bin/env python3
#
# Author:
# Tamas Jos (@skelsec)
#
import os
import logging
import asyncio
from minikerberos.common.url import KerberosClientURL, kerberos_url_help_epilog
from minikerberos.common.spn import KerberosSPN
from minikerberos.aioclient import AIOKerberosClient
async def amain(args):
if args.spn.find('@') == -1:
raise Exception('SPN must contain @')
t, domain = args.spn.split('@')
if t.find('/') != -1:
service, hostname = args.spn.split('/')
else:
hostname = t
service = None
spn = KerberosSPN()
spn.username = hostname
spn.service = service
spn.domain = domain
cu = KerberosClientURL.from_url(args.kerberos_connection_url)
ccred = cu.get_creds()
target = cu.get_target()
logging.debug('Getting TGT')
if not ccred.ccache:
client = AIOKerberosClient(ccred, target)
logging.debug('Getting TGT')
await client.get_TGT()
logging.debug('Getting TGS')
await client.get_TGS(spn)
else:
logging.debug('Getting TGS via TGT from CCACHE')
for tgt, key in ccred.ccache.get_all_tgt():
try:
logging.info('Trying to get SPN with %s' % '!'.join(tgt['cname']['name-string']))
client = AIOKerberosClient.from_tgt(target, tgt, key)
await client.get_TGS(spn)
logging.info('Sucsess!')
except Exception as e:
logging.debug('This ticket is not usable it seems Reason: %s' % e)
continue
else:
break
client.ccache.to_file(args.ccache)
logging.info('Done!')
def main():
import argparse
parser = argparse.ArgumentParser(description='Polls the kerberos service for a TGS for the sepcified user and specified service', formatter_class=argparse.RawDescriptionHelpFormatter, epilog = kerberos_url_help_epilog)
parser.add_argument('kerberos_connection_string', help='the kerberos target string in the following format <domain>/<username>/<secret_type>:<secret>@<domaincontroller-ip>')
parser.add_argument('spn', help='the service principal in format <service>/<server-hostname>@<domain> Example: cifs/fileserver.test.corp@TEST.corp for a TGS ticket to be used for file access on server "fileserver". IMPORTANT: SERVER\'S HOSTNAME MUST BE USED, NOT IP!!!')
parser.add_argument('ccache', help='ccache file to store the TGT ticket in')
parser.add_argument('-u', action='store_true', help='Use UDP instead of TCP (not tested)')
parser.add_argument('-v', '--verbose', action='count', default=0)
args = parser.parse_args()
if args.verbose == 0:
logging.basicConfig(level=logging.INFO)
elif args.verbose == 1:
logging.basicConfig(level=logging.DEBUG)
else:
logging.basicConfig(level=1)
asyncio.run(amain(args))
if __name__ == '__main__':
main()
