# Copyright (c) 2003-2016 CORE Security Technologies
#
# This software is provided under under a slightly modified version
# of the Apache Software License. See the accompanying LICENSE file
# for more information.
#
# Service Install Helper library used by psexec and smbrelayx
# You provide an already established connection and an exefile
# (or class that mimics a file class) and this will install and
# execute the service, and then uninstall (install(), uninstall().
# It tries to take care as much as possible to leave everything clean.
#
# Author:
# Alberto Solino (@agsolino)
#
import random
import string
from impacket.dcerpc.v5 import transport, srvs, scmr
from impacket import smb,smb3, LOG
from impacket.smbconnection import SMBConnection
class ServiceInstall:
def __init__(self, SMBObject, exeFile):
self._rpctransport = 0
self.__service_name = ''.join([random.choice(string.letters) for i in range(4)])
self.__binary_service_name = ''.join([random.choice(string.letters) for i in range(8)]) + '.exe'
self.__exeFile = exeFile
# We might receive two different types of objects, always end up
# with a SMBConnection one
if isinstance(SMBObject, smb.SMB) or isinstance(SMBObject, smb3.SMB3):
self.connection = SMBConnection(existingConnection = SMBObject)
else:
self.connection = SMBObject
self.share = ''
def getShare(self):
return self.share
def getShares(self):
# Setup up a DCE SMBTransport with the connection already in place
LOG.info("Requesting shares on %s....." % (self.connection.getRemoteHost()))
try:
self._rpctransport = transport.SMBTransport(self.connection.getRemoteHost(), self.connection.getRemoteHost(),filename = r'\srvsvc', smb_connection = self.connection)
dce_srvs = self._rpctransport.get_dce_rpc()
dce_srvs.connect()
dce_srvs.bind(srvs.MSRPC_UUID_SRVS)
resp = srvs.hNetrShareEnum(dce_srvs, 1)
return resp['InfoStruct']['ShareInfo']['Level1']
except:
LOG.critical("Error requesting shares on %s, aborting....." % (self.connection.getRemoteHost()))
raise
def createService(self, handle, share, path):
LOG.info("Creating service %s on %s....." % (self.__service_name, self.connection.getRemoteHost()))
# First we try to open the service in case it exists. If it does, we remove it.
try:
resp = scmr.hROpenServiceW(self.rpcsvc, handle, self.__service_name+'\x00')
except Exception, e:
if str(e).find('ERROR_SERVICE_DOES_NOT_EXIST') >= 0:
# We're good, pass the exception
pass
else:
raise e
else:
# It exists, remove it
scmr.hRDeleteService(self.rpcsvc, resp['lpServiceHandle'])
scmr.hRCloseServiceHandle(self.rpcsvc, resp['lpServiceHandle'])
# Create the service
command = '%s\\%s' % (path, self.__binary_service_name)
try:
resp = scmr.hRCreateServiceW(self.rpcsvc, handle,self.__service_name + '\x00', self.__service_name + '\x00', lpBinaryPathName=command + '\x00')
except:
LOG.critical("Error creating service %s on %s" % (self.__service_name, self.connection.getRemoteHost()))
raise
else:
return resp['lpServiceHandle']
def openSvcManager(self):
LOG.info("Opening SVCManager on %s....." % self.connection.getRemoteHost())
# Setup up a DCE SMBTransport with the connection already in place
self._rpctransport = transport.SMBTransport(self.connection.getRemoteHost(), self.connection.getRemoteHost(),filename = r'\svcctl', smb_connection = self.connection)
self.rpcsvc = self._rpctransport.get_dce_rpc()
self.rpcsvc.connect()
self.rpcsvc.bind(scmr.MSRPC_UUID_SCMR)
try:
resp = scmr.hROpenSCManagerW(self.rpcsvc)
except:
LOG.critical("Error opening SVCManager on %s....." % self.connection.getRemoteHost())
raise Exception('Unable to open SVCManager')
else:
return resp['lpScHandle']
def copy_file(self, src, tree, dst):
LOG.info("Uploading file %s" % dst)
if isinstance(src, str):
# We have a filename
fh = open(src, 'rb')
else:
# We have a class instance, it must have a read method
fh = src
f = dst
pathname = string.replace(f,'/','\\')
try:
self.connection.putFile(tree, pathname, fh.read)
except:
LOG.critical("Error uploading file %s, aborting....." % dst)
raise
fh.close()
def findWritableShare(self, shares):
# Check we can write a file on the shares, stop in the first one
for i in shares['Buffer']:
if i['shi1_type'] == srvs.STYPE_DISKTREE or i['shi1_type'] == srvs.STYPE_SPECIAL:
share = i['shi1_netname'][:-1]
try:
self.connection.createDirectory(share,'BETO')
except:
# Can't create, pass
LOG.critical("share '%s' is not writable." % share)
pass
else:
LOG.info('Found writable share %s' % share)
self.connection.deleteDirectory(share,'BETO')
return str(share)
return None
def install(self):
if self.connection.isGuestSession():
LOG.critical("Authenticated as Guest. Aborting")
self.connection.logoff()
del self.connection
else:
fileCopied = False
serviceCreated = False
# Do the stuff here
try:
# Let's get the shares
shares = self.getShares()
self.share = self.findWritableShare(shares)
if self.share is None:
return False
self.copy_file(self.__exeFile ,self.share,self.__binary_service_name)
fileCopied = True
svcManager = self.openSvcManager()
if svcManager != 0:
serverName = self.connection.getServerName()
if self.share.lower() == 'admin$':
path = '%systemroot%'
else:
if serverName != '':
path = '\\\\%s\\%s' % (serverName, self.share)
else:
path = '\\\\127.0.0.1\\' + self.share
service = self.createService(svcManager, self.share, path)
serviceCreated = True
if service != 0:
# Start service
LOG.info('Starting service %s.....' % self.__service_name)
try:
scmr.hRStartServiceW(self.rpcsvc, service)
except:
pass
scmr.hRCloseServiceHandle(self.rpcsvc, service)
scmr.hRCloseServiceHandle(self.rpcsvc, svcManager)
return True
except Exception, e:
LOG.critical("Error performing the installation, cleaning up: %s" %e)
try:
scmr.hRControlService(self.rpcsvc, service, scmr.SERVICE_CONTROL_STOP)
except:
pass
if fileCopied is True:
try:
self.connection.deleteFile(self.share, self.__binary_service_name)
except:
pass
if serviceCreated is True:
try:
scmr.hRDeleteService(self.rpcsvc, service)
except:
pass
return False
def uninstall(self):
fileCopied = True
serviceCreated = True
# Do the stuff here
try:
# Let's get the shares
svcManager = self.openSvcManager()
if svcManager != 0:
resp = scmr.hROpenServiceW(self.rpcsvc, svcManager, self.__service_name+'\x00')
service = resp['lpServiceHandle']
LOG.info('Stoping service %s.....' % self.__service_name)
try:
scmr.hRControlService(self.rpcsvc, service, scmr.SERVICE_CONTROL_STOP)
except:
pass
LOG.info('Removing service %s.....' % self.__service_name)
scmr.hRDeleteService(self.rpcsvc, service)
scmr.hRCloseServiceHandle(self.rpcsvc, service)
scmr.hRCloseServiceHandle(self.rpcsvc, svcManager)
LOG.info('Removing file %s.....' % self.__binary_service_name)
self.connection.deleteFile(self.share, self.__binary_service_name)
except Exception:
LOG.critical("Error performing the uninstallation, cleaning up" )
try:
scmr.hRControlService(self.rpcsvc, service, scmr.SERVICE_CONTROL_STOP)
except:
pass
if fileCopied is True:
try:
self.connection.deleteFile(self.share, self.__binary_service_name)
except:
try:
self.connection.deleteFile(self.share, self.__binary_service_name)
except:
pass
pass
if serviceCreated is True:
try:
scmr.hRDeleteService(self.rpcsvc, service)
except:
pass
