#!/usr/bin/env python
# SECUREAUTH LABS. Copyright 2018 SecureAuth Corporation. All rights reserved.
#
# This software is provided under under a slightly modified version
# of the Apache Software License. See the accompanying LICENSE file
# for more information.
#
# Author:
#  beto (@agsolino)
#
# Description:
#   The idea of this script is to get a list of the sessions
#   opened at the remote hosts and keep track of them.
#   Coincidentally @mubix did something similar a few years
#   ago so credit goes to him (and the script's name ;)).
#   Check it out at https://github.com/mubix/netview
#   The main difference with our approach is we keep 
#   looping over the hosts found and keep track of who logged
#   in/out from remote servers. Plus, we keep the connections
#   with the target systems and just send a few DCE-RPC packets.
#
#   One VERY IMPORTANT thing is:
#   
#   YOU HAVE TO BE ABLE TO RESOLV THE DOMAIN MACHINES NETBIOS 
#   NAMES. That's usually solved by setting your DNS to the 
#   domain DNS (and the right search domain).
#   
#   Some examples of usage are:
#
#   netview.py -target 192.168.1.10 beto
#   
#   This will show the sessions on 192.168.1.10 and will authenticate as 'beto'
#   (password will be prompted)
#
#   netview.py FREEFLY.NET/beto
#
#   This will download all machines from FREEFLY.NET, authenticated as 'beto'
#   and will gather the session information for those machines that appear
#   to be up. There is a background thread checking aliveness of the targets
#   at all times.
#
#   netview.py -users /tmp/users -dc-ip freefly-dc.freefly.net -k FREEFLY.NET/beto
#  
#   This will download all machines from FREEFLY.NET, authenticating using
#   Kerberos (that's why -dc-ip parameter is needed), and filter
#   the output based on the list of users specified in /tmp/users file.
#
#
from __future__ import division
from __future__ import print_function
import sys
import argparse
import logging
import socket
from threading import Thread, Event
from queue import Queue
from time import sleep

from impacket.examples import logger
from impacket.examples.utils import parse_credentials
from impacket import version
from impacket.smbconnection import SessionError
from impacket.dcerpc.v5 import transport, wkst, srvs, samr
from impacket.dcerpc.v5.ndr import NULL
from impacket.dcerpc.v5.rpcrt import DCERPCException
from impacket.nt_errors import STATUS_MORE_ENTRIES

machinesAliveQueue = Queue()
machinesDownQueue = Queue()

myIP = None


def checkMachines(machines, stopEvent, singlePass=False):
    origLen = len(machines)
    deadMachines = machines
    done = False
    while not done:
        if stopEvent.is_set():
             done = True
             break
        for machine in deadMachines:
            s = socket.socket()
            try:
                s = socket.create_connection((machine, 445), 2)
                global myIP
                myIP = s.getsockname()[0]
                s.close()
                machinesAliveQueue.put(machine)
            except Exception as e:
                logging.debug('%s: not alive (%s)' % (machine, e))
                pass
            else:
                logging.debug('%s: alive!' % machine)
                deadMachines.remove(machine)
            if stopEvent.is_set():
                 done = True
                 break

        logging.debug('up: %d, down: %d, total: %d' % (origLen-len(deadMachines), len(deadMachines), origLen))
        if singlePass is True:
            done = True
        if not done:
            sleep(10)
            # Do we have some new deadMachines to add?
            while machinesDownQueue.empty() is False:
                deadMachines.append(machinesDownQueue.get())

class USERENUM:
    def __init__(self, username='', password='', domain='', hashes=None, aesKey=None, doKerberos=False, options=None):
        self.__username = username
        self.__password = password
        self.__domain = domain
        self.__lmhash = ''
        self.__nthash = ''
        self.__aesKey = aesKey
        self.__doKerberos = doKerberos
        self.__kdcHost = options.dc_ip
        self.__options = options
        self.__machinesList = list()
        self.__targets = dict()
        self.__filterUsers = None
        self.__targetsThreadEvent = None
        self.__targetsThread = None
        self.__maxConnections = int(options.max_connections)
        if hashes is not None:
            self.__lmhash, self.__nthash = hashes.split(':')

    def getDomainMachines(self):
        if self.__kdcHost is not None:
            domainController = self.__kdcHost
        elif self.__domain != '':
            domainController = self.__domain
        else:
            raise Exception('A domain is needed!')

        logging.info('Getting machine\'s list from %s' % domainController)
        rpctransport = transport.SMBTransport(domainController, 445, r'\samr', self.__username, self.__password,
                                              self.__domain, self.__lmhash, self.__nthash, self.__aesKey,
                                              doKerberos=self.__doKerberos, kdcHost = self.__kdcHost)
        dce = rpctransport.get_dce_rpc()
        dce.connect()
        dce.bind(samr.MSRPC_UUID_SAMR)
        try:
            resp = samr.hSamrConnect(dce)
            serverHandle = resp['ServerHandle'] 

            resp = samr.hSamrEnumerateDomainsInSamServer(dce, serverHandle)
            domains = resp['Buffer']['Buffer']

            logging.info("Looking up users in domain %s" % domains[0]['Name'])

            resp = samr.hSamrLookupDomainInSamServer(dce, serverHandle,domains[0]['Name'] )

            resp = samr.hSamrOpenDomain(dce, serverHandle = serverHandle, domainId = resp['DomainId'])
            domainHandle = resp['DomainHandle']

            status = STATUS_MORE_ENTRIES
            enumerationContext = 0
            while status == STATUS_MORE_ENTRIES:
                try:
                    resp = samr.hSamrEnumerateUsersInDomain(dce, domainHandle, samr.USER_WORKSTATION_TRUST_ACCOUNT,
                                                            enumerationContext=enumerationContext)
                except DCERPCException as e:
                    if str(e).find('STATUS_MORE_ENTRIES') < 0:
                        raise
                    resp = e.get_packet()

                for user in resp['Buffer']['Buffer']:
                    self.__machinesList.append(user['Name'][:-1])
                    logging.debug('Machine name - rid: %s - %d'% (user['Name'], user['RelativeId']))

                enumerationContext = resp['EnumerationContext'] 
                status = resp['ErrorCode']
        except Exception as e:
            raise e

        dce.disconnect()

    def getTargets(self):
        logging.info('Importing targets')
        if self.__options.target is None and self.__options.targets is None:
            # We need to download the list of machines from the domain
            self.getDomainMachines()
        elif self.__options.targets is not None:
            for line in self.__options.targets.readlines():
                self.__machinesList.append(line.strip(' \r\n'))
        else:
            # Just a single machine
            self.__machinesList.append(self.__options.target)
        logging.info("Got %d machines" % len(self.__machinesList))
          
    def filterUsers(self):
        if self.__options.user is not None:
            self.__filterUsers = list()
            self.__filterUsers.append(self.__options.user)
        elif self.__options.users is not None:
            # Grab users list from a file
            self.__filterUsers = list()
            for line in self.__options.users.readlines():
                self.__filterUsers.append(line.strip(' \r\n'))
        else:
            self.__filterUsers = None

    def run(self):
        self.getTargets()
        self.filterUsers()
        #self.filterGroups()
       
        # Up to here we should have figured out the scope of our work
        self.__targetsThreadEvent = Event()
        if self.__options.noloop is False:
            # Start a separate thread checking the targets that are up
            self.__targetsThread = Thread(target=checkMachines, args=(self.__machinesList,self.__targetsThreadEvent))
            self.__targetsThread.start()
        else:
            # Since it's gonna be a one shoot test, we need to wait till it finishes
            checkMachines(self.__machinesList,self.__targetsThreadEvent, singlePass=True)

        while True:
            # Do we have more machines to add?
            while machinesAliveQueue.empty() is False:
                machine = machinesAliveQueue.get()
                logging.debug('Adding %s to the up list' % machine)
                self.__targets[machine] = {}
                self.__targets[machine]['SRVS'] = None
                self.__targets[machine]['WKST'] = None
                self.__targets[machine]['Admin'] = True
                self.__targets[machine]['Sessions'] = list()
                self.__targets[machine]['LoggedIn'] = set()
            
            for target in list(self.__targets.keys()):
                try:
                    self.getSessions(target)
                    self.getLoggedIn(target) 
                except (SessionError, DCERPCException) as e:
                    # We will silently pass these ones, might be issues with Kerberos, or DCE
                    if str(e).find('LOGON_FAILURE') >=0:
                        # For some reason our credentials don't work there, 
                        # taking it out from the list.
                        logging.error('STATUS_LOGON_FAILURE for %s, discarding' % target)
                        del(self.__targets[target])
                    elif str(e).find('INVALID_PARAMETER') >=0:
                        del(self.__targets[target])
                    elif str(e).find('access_denied') >=0:
                        # Can't access the target RPC call, most probably a Unix host
                        # taking it out from the list
                        del(self.__targets[target])
                    else:
                        logging.info(str(e))
                    pass 
                except KeyboardInterrupt:
                    raise
                except Exception as e:
                    #import traceback
                    #traceback.print_exc()
                    if str(e).find('timed out') >=0:
                        # Most probably this site went down. taking it out
                        # ToDo: add it back to the list of machines to check in
                        # the separate thread - DONE
                        del(self.__targets[target])
                        machinesDownQueue.put(target)
                    else:
                        # These ones we will report
                        logging.error(e)
                    pass

            if self.__options.noloop is True:
                break

            logging.debug('Sleeping for %s seconds' % self.__options.delay)
            logging.debug('Currently monitoring %d active targets' % len(self.__targets))
            sleep(int(self.__options.delay))

    def getSessions(self, target):
        if self.__targets[target]['SRVS'] is None:
            stringSrvsBinding = r'ncacn_np:%s[\PIPE\srvsvc]' % target
            rpctransportSrvs = transport.DCERPCTransportFactory(stringSrvsBinding)
            if hasattr(rpctransportSrvs, 'set_credentials'):
            # This method exists only for selected protocol sequences.
                rpctransportSrvs.set_credentials(self.__username, self.__password, self.__domain, self.__lmhash,
                                                 self.__nthash, self.__aesKey)
                rpctransportSrvs.set_kerberos(self.__doKerberos, self.__kdcHost)

            dce = rpctransportSrvs.get_dce_rpc()
            dce.connect()
            dce.bind(srvs.MSRPC_UUID_SRVS)
            self.__maxConnections -= 1
        else:
            dce = self.__targets[target]['SRVS']

        try:
            resp = srvs.hNetrSessionEnum(dce, '\x00', NULL, 10)
        except Exception as e:
            if str(e).find('Broken pipe') >= 0:
                # The connection timed-out. Let's try to bring it back next round
                self.__targets[target]['SRVS'] = None
                self.__maxConnections += 1
                return
            else:
                raise

        if self.__maxConnections < 0:
            # Can't keep this connection open. Closing it
            dce.disconnect()
            self.__maxConnections = 0
        else:
             self.__targets[target]['SRVS'] = dce

        # Let's see who createad a connection since last check
        tmpSession = list()
        printCRLF = False
        for session in resp['InfoStruct']['SessionInfo']['Level10']['Buffer']:
            userName = session['sesi10_username'][:-1]
            sourceIP = session['sesi10_cname'][:-1][2:]
            key = '%s\x01%s' % (userName, sourceIP)
            myEntry = '%s\x01%s' % (self.__username, myIP)
            tmpSession.append(key)
            if not(key in self.__targets[target]['Sessions']):
                # Skipping myself
                if key != myEntry:
                    self.__targets[target]['Sessions'].append(key)
                    # Are we filtering users?
                    if self.__filterUsers is not None:
                        if userName in self.__filterUsers:
                            print("%s: user %s logged from host %s - active: %d, idle: %d" % (
                            target, userName, sourceIP, session['sesi10_time'], session['sesi10_idle_time']))
                            printCRLF = True
                    else:
                        print("%s: user %s logged from host %s - active: %d, idle: %d" % (
                        target, userName, sourceIP, session['sesi10_time'], session['sesi10_idle_time']))
                        printCRLF = True

        # Let's see who deleted a connection since last check
        for nItem, session in enumerate(self.__targets[target]['Sessions']):
            userName, sourceIP = session.split('\x01')
            if session not in tmpSession:
                del(self.__targets[target]['Sessions'][nItem])
                # Are we filtering users?
                if self.__filterUsers is not None:
                    if userName in self.__filterUsers:
                        print("%s: user %s logged off from host %s" % (target, userName, sourceIP))
                        printCRLF=True
                else:
                    print("%s: user %s logged off from host %s" % (target, userName, sourceIP))
                    printCRLF=True
                
        if printCRLF is True:
            print()
        
    def getLoggedIn(self, target):
        if self.__targets[target]['Admin'] is False:
            return

        if self.__targets[target]['WKST'] is None:
            stringWkstBinding = r'ncacn_np:%s[\PIPE\wkssvc]' % target
            rpctransportWkst = transport.DCERPCTransportFactory(stringWkstBinding)
            if hasattr(rpctransportWkst, 'set_credentials'):
                # This method exists only for selected protocol sequences.
                rpctransportWkst.set_credentials(self.__username, self.__password, self.__domain, self.__lmhash,
                                                 self.__nthash, self.__aesKey)
                rpctransportWkst.set_kerberos(self.__doKerberos, self.__kdcHost)

            dce = rpctransportWkst.get_dce_rpc()
            dce.connect()
            dce.bind(wkst.MSRPC_UUID_WKST)
            self.__maxConnections -= 1
        else:
            dce = self.__targets[target]['WKST']

        try:
            resp = wkst.hNetrWkstaUserEnum(dce,1)
        except Exception as e:
            if str(e).find('Broken pipe') >= 0:
                # The connection timed-out. Let's try to bring it back next round
                self.__targets[target]['WKST'] = None
                self.__maxConnections += 1
                return
            elif str(e).upper().find('ACCESS_DENIED'):
                # We're not admin, bye
                dce.disconnect()
                self.__maxConnections += 1
                self.__targets[target]['Admin'] = False
                return
            else:
                raise

        if self.__maxConnections < 0:
            # Can't keep this connection open. Closing it
            dce.disconnect()
            self.__maxConnections = 0
        else:
             self.__targets[target]['WKST'] = dce

        # Let's see who looged in locally since last check
        tmpLoggedUsers = set()
        printCRLF = False
        for session in resp['UserInfo']['WkstaUserInfo']['Level1']['Buffer']:
            userName = session['wkui1_username'][:-1]
            logonDomain = session['wkui1_logon_domain'][:-1]
            key = '%s\x01%s' % (userName, logonDomain)
            tmpLoggedUsers.add(key)
            if not(key in self.__targets[target]['LoggedIn']):
                self.__targets[target]['LoggedIn'].add(key)
                # Are we filtering users?
                if self.__filterUsers is not None:
                    if userName in self.__filterUsers:
                        print("%s: user %s\\%s logged in LOCALLY" % (target,logonDomain,userName))
                        printCRLF=True
                else:
                    print("%s: user %s\\%s logged in LOCALLY" % (target,logonDomain,userName))
                    printCRLF=True

        # Let's see who logged out since last check
        for session in self.__targets[target]['LoggedIn'].copy():
            userName, logonDomain = session.split('\x01')
            if session not in tmpLoggedUsers:
                self.__targets[target]['LoggedIn'].remove(session)
                # Are we filtering users?
                if self.__filterUsers is not None:
                    if userName in self.__filterUsers:
                        print("%s: user %s\\%s logged off LOCALLY" % (target,logonDomain,userName))
                        printCRLF=True
                else:
                    print("%s: user %s\\%s logged off LOCALLY" % (target,logonDomain,userName))
                    printCRLF=True
                
        if printCRLF is True:
            print()

    def stop(self):
        if self.__targetsThreadEvent is not None:
            self.__targetsThreadEvent.set()
        

# Process command-line arguments.
if __name__ == '__main__':
    print(version.BANNER)

    parser = argparse.ArgumentParser()

    parser.add_argument('identity', action='store', help='[domain/]username[:password]')
    parser.add_argument('-user', action='store', help='Filter output by this user')
    parser.add_argument('-users', type=argparse.FileType('r'), help='input file with list of users to filter to output for')
    #parser.add_argument('-group', action='store', help='Filter output by members of this group')
    #parser.add_argument('-groups', type=argparse.FileType('r'), help='Filter output by members of the groups included in the input file')
    parser.add_argument('-target', action='store', help='target system to query info from. If not specified script will '
                                                        'run in domain mode.')
    parser.add_argument('-targets', type=argparse.FileType('r'), help='input file with targets system to query info '
                        'from (one per line). If not specified script will run in domain mode.')
    parser.add_argument('-noloop', action='store_true', default=False, help='Stop after the first probe')
    parser.add_argument('-delay', action='store', default = '10', help='seconds delay between starting each batch probe '
                                                                       '(default 10 seconds)')
    parser.add_argument('-max-connections', action='store', default='1000', help='Max amount of connections to keep '
                                                                                 'opened (default 1000)')
    parser.add_argument('-ts', action='store_true', help='Adds timestamp to every logging output')
    parser.add_argument('-debug', action='store_true', help='Turn DEBUG output ON')

    group = parser.add_argument_group('authentication')

    group.add_argument('-hashes', action="store", metavar = "LMHASH:NTHASH", help='NTLM hashes, format is LMHASH:NTHASH')
    group.add_argument('-no-pass', action="store_true", help='don\'t ask for password (useful for -k)')
    group.add_argument('-k', action="store_true", help='Use Kerberos authentication. Grabs credentials from ccache file '
                       '(KRB5CCNAME) based on target parameters. If valid credentials cannot be found, it will use the '
                       'ones specified in the command line')
    group.add_argument('-aesKey', action="store", metavar = "hex key", help='AES key to use for Kerberos Authentication '
                                                                            '(128 or 256 bits)')
    group.add_argument('-dc-ip', action='store',metavar = "ip address",  help='IP Address of the domain controller. If '
                       'ommited it use the domain part (FQDN) specified in the target parameter')

    if len(sys.argv)==1:
        parser.print_help()
        sys.exit(1)

    options = parser.parse_args()

    # Init the example's logger theme
    logger.init(options.ts)

    if options.debug is True:
        logging.getLogger().setLevel(logging.DEBUG)
        # Print the Library's installation path
        logging.debug(version.getInstallationPath())
    else:
        logging.getLogger().setLevel(logging.INFO)

    domain, username, password = parse_credentials(options.identity)

    try:
        if domain is None:
            domain = ''

        if password == '' and username != '' and options.hashes is None and options.no_pass is False and options.aesKey is None:
            from getpass import getpass
            password = getpass("Password:")

        if options.aesKey is not None:
            options.k = True

        executer = USERENUM(username, password, domain, options.hashes, options.aesKey, options.k, options)
        executer.run()
    except Exception as e:
        if logging.getLogger().level == logging.DEBUG:
            import traceback
            traceback.print_exc()
        logging.error(e)
        executer.stop()
    except KeyboardInterrupt:
        logging.info('Quitting.. please wait') 
        executer.stop()
    sys.exit(0)
