查找恶意的TOR中继节点

原文链接:
http://blog.51cto.com/cxnic/1727685

众所周知,TOR是一种能够保护世界各地不同中继节点之间通信调度数据包的“软件”,由志愿者建立的网络进行运营。在过去的几年中,TOR已经被物理和网络***者广泛用于掩盖恶意操作。TOR也被视为最主要的进入暗网的方法,在暗网中,“恶意”的人可以通过黑市非法买卖东西。

网络里每个中继节点都能够根据自己的配置状态,决定是作为一个ExitPoint(在以下图片中用最后一台接触“Bob”的机器表示)或者只是一个中继节点(在下图中,TOR节点用“绿十字”突出显示)。如果中继节点决定成为一个ExitNode,就会向公众公开自己的IP地址,这通常是一个引起当地警方警觉的好办法。

50dc118cc05c3318048defc5c68f39f2.png

过去一年中,电视节目,广播电台,youtube频道,Facebook这一类大众媒体披露出,许多黑市故意将人们引向DarkWeb,从而将他们暴露在许多新的***场景下。事实上新的***者会为了监视他们的通信流而设置退出节点或继电器节点。这种***可能会在许多单一的方式下发生,但最常用的今天写的这三个:

1.DNS中毒:这个技术主要在于将与知名网站有关的DNS调用重定向到一个假的页面上, 这个假的页面包含开发工具包,可以使用户的浏览器妥协。

2.文件修补:这个技术是改变请求的文件,在其到达目的地之前在其中添加恶意内容.这些步骤会在发给原始请求者之前直接在ExitPoint /中继节点上进行。

3.替换证明(SSL – MITM):这个技术是用假的证书替换网站真实的证书,这样就可以解密通信流,拦截凭证和参数。

致力于网络安全就意味着要及时意识到这样的***的存在,也要能够决定将在何时通过TOR中继节点。请注意,TOR不是DarkWeb中唯一的匿名网络.

我的目标是弄清楚我的TOR流通过恶意中继节点的时间。出于这样一个原因,我决定写一个能够对DNS Poison,文件修补和SSL-MITM做出一些快速检查的python脚本。这个脚本已经存在了2年, 直到现在仍是保密状态。自从科学研究应用了我的FindMalExit.py的高级版本之后,我决定公开这个脚本。

想法

实际上这是一个非常简单的想法:“让我们在不通过TOR网络(或通过可靠电路)的情况下拿到证书,IP地址和文件,然后重复这个过程,直到通过所有可用的中继节点。比较结果并进行检查。”

实现

以下请查收我的代码。请记住这是一个不是最终的代码 (这段代码只是一个更大的项目中的第一个版本,现在由Yoroi维护)。我决定发布HTML格式的代码。

#!/usr/bin/env python2
#========================================================================#
#               THIS IS NOT A PRODUCTION RELEASED SOFTWARE               #
#========================================================================#
# Purpose of finMaliciousRelayPoints is to proof the way it's possible to#
# discover TOR malicious Relays Points. Please do not use it in          #
# any production  environment                                            #
# Author: Marco Ramilli                                                  #
# eMail: XXXXXXXX                                                        #
# WebSite: marcoramilli.blogspot.com                                     #
# Use it at your own                                                     #
#========================================================================#
#==============================Disclaimer: ==============================#
#THIS SOFTWARE IS PROVIDED BY THE AUTHOR "AS IS" AND ANY EXPRESS OR      #
#IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED          #
#WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE  #
#DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,      #
#INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES      #
#(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR      #
#SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)      #
#HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,     #
#STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING   #
#IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE      #
#POSSIBILITY OF SUCH DAMAGE.                                             #
#========================================================================#
#-------------------------------------------------------------------------
#------------------- GENERAL SECTION -------------------------------------
#-------------------------------------------------------------------------
import StringIO
import tempfile
import time
import hashlib
import traceback
from   geoip         import  geolite2
import stem.control
TRUSTED_HOP_FINGERPRINT = '379FB450010D17078B3766C2273303C358C3A442'
#trusted hop
SOCKS_PORT              = 9050
CONNECTION_TIMEOUT      = 30  # timeout before we give up on a circuit
#-------------------------------------------------------------------------
#---------------- File Patching Section ----------------------------------
#-------------------------------------------------------------------------
import pycurl
check_files               = {
                            "http://live.sysinternals.com/psexec.exe",
                            "http://live.sysinternals.com/psexec.exe",
                            "http://live.sysinternals.com/psping.exe", }
check_files_patch_results = []
class File_Check_Results:
   """
   Analysis Results against File Patching
   """
   def __init__(self, url, filen, filepath, exitnode, found_hash):
       self.url           = url
       self.filename      = filen
       self.filepath      = filepath
       self.exitnode      = exitnode
       self.filehash      = found_hash
#------------------------------------------------------------------------
#------------------- DNS Poison Section ---------------------------------
#------------------------------------------------------------------------
import dns.resolver
import socks
import socket
check_domain_poison_results = []
domains                     = {
                                "www.youporn.com",
                                "youporn.com",
                                "www.torproject.org",
                                "www.wikileaks.org",
                                "www.i2p2.de",
                                "torrentfreak.com",
                                "blockchain.info",
}
class Domain_Poison_Check:
   """
   Analysis Results against Domain Poison
   """
   def __init__(self, domain):
       self.domain  = domain
       self.address = []
       self.path    = []
   def pushAddr(self, add):
       self.address.append(add)
   def pushPath(self, path):
       self.path = path
#-----------------------------------------------------------------------
#------------------- SSL Sltrip Section --------------------------------
#-----------------------------------------------------------------------
import OpenSSL
import ssl
check_ssl_strip_results   = []
ssl_strip_monitored_urls = {
                           "www.google.com",
                           "www.microsoft.com",
                           "www.apple.com",
                           "www.bbc.com",
}
class SSL_Strip_Check:
   """
   Analysis Result against SSL Strip
   """
   def __init__(self, domain, public_key, serial_number):
       self.domain        = domain
       self.public_key    = public_key
       self.serial_number = serial_number
#----------------------------------------------------------------------
#----------------     Starting Coding   -------------------------------
#----------------------------------------------------------------------
def sslCheckOriginal():
   """
   Download the original Certificate without TOR connection
   """
   print('[+] Populating SSL for later check')
   for url in ssl_strip_monitored_urls:
       try:
           cert = ssl.get_server_certificate((str(url), 443))
           x509 = OpenSSL.crypto.load_certificate(OpenSSL.crypto.FILETYPE_PEM, cert)
           p_k  = x509.get_pubkey()
           s_n  = x509.get_serial_number()
           print('[+] Acquired Certificate: %s' % url)
           print('    |_________> serial_number %s' % s_n)
           print('    |_________> public_key %s' % p_k)
           check_ssl_strip_results.append(SSL_Strip_Check(url, p_k, s_n))
       except Exception as err:
           print('[-] Error While Acquiring certificats on setup phase !')
           traceback.print_exc()
   return time.time()
def fileCheckOriginal():
   """
   Downloading file ORIGINAL without TOR
   """
   print('[+] Populating File Hasing for later check')
   for url in check_files:
       try:
           data = query(url)
           file_name = url.split("/")[-1]
           _,tmp_file = tempfile.mkstemp(prefix="exitmap_%s_" % file_name)
           with open(tmp_file, "wb") as fd:
               fd.write(data)
               print('[+] Saving File  \"%s\".' % tmp_file)
               check_files_patch_results.append( File_Check_Results(url, file_name, tmp_file, "NO", sha512_file(tmp_file)) )
               print('[+] First Time we see the file..')
               print('    |_________> exitnode : None'       )
               print('    |_________> :url:  %s' % str(url)     )
               print('    |_________> :filePath:  %s' % str(tmp_file))
               print('    |_________> :file Hash: %s' % str(sha512_file(tmp_file)))
       except Exception as err:
               print('[-] Error ! %s' % err)
               traceback.print_exc()
               pass
   return time.time()
def resolveOriginalDomains():
   """
       Resolving DNS For original purposes
   """
   print('[+] Populating Domain Name Resolution for later check ')
   try:
       for domain in domains:
           response = dns.resolver.query(domain)
           d = Domain_Poison_Check(domain)
           print('[+] Domain: %s' % domain)
           for record in response:
               print(' |____> maps to %s.' % (record.address))
               d.pushAddr(record)
           check_domain_poison_results.append(d)
       return time.time()
   except Exception as err:
       print('[+] Exception: %s' % err)
       traceback.print_exc()
       return time.time()
def query(url):
 """
 Uses pycurl to fetch a site using the proxy on the SOCKS_PORT.
 """
 output = StringIO.StringIO()
 query = pycurl.Curl()
 query.setopt(pycurl.URL, url)
 query.setopt(pycurl.PROXY, 'localhost')
 query.setopt(pycurl.PROXYPORT, SOCKS_PORT)
 query.setopt(pycurl.PROXYTYPE, pycurl.PROXYTYPE_SOCKS5_HOSTNAME)
 query.setopt(pycurl.CONNECTTIMEOUT, CONNECTION_TIMEOUT)
 query.setopt(pycurl.WRITEFUNCTION, output.write)
 try:
   query.perform()
   return output.getvalue()
 except pycurl.error as exc:
   raise ValueError("Unable to reach %s (%s)" % (url, exc))
def scan(controller, path):
 """
 Scan Tor Relays Point to find File Patching
 """
 def attach_stream(stream):
   if stream.status == 'NEW':
     try:
       controller.attach_stream(stream.id, circuit_id)
       #print('[+] New Circuit id (%s) attached and ready to be used!' % circuit_id)
     except Exception as err:
       controller.remove_event_listener(attach_stream)
       controller.reset_conf('__LeaveStreamsUnattached')
 try:
   print('[+] Creating a New TOR circuit based on path: %s' % path)
   circuit_id = controller.new_circuit(path, await_build = True)
   controller.add_event_listener(attach_stream, stem.control.EventType.STREAM)
   controller.set_conf('__LeaveStreamsUnattached', '1')  # leave stream management to us
   start_time = time.time()
   socks.setdefaultproxy(socks.PROXY_TYPE_SOCKS5, "127.0.0.1", 9050)
   socket.socket = socks.socket
   ip = query('http://ip.42.pl/raw')
   if ip is not None:
       country  = geolite2.lookup( str(ip) ).country
       print('\n \n')
       print('[+] Performing FilePatch,  DNS Spoofing and Certificate Checking\
             passing through --> %s (%s) \n \n' % (str(ip), str(country))  )
   time_FileCheck = fileCheck(path)
   print('[+] FileCheck took: %0.2f seconds'  % ( time_FileCheck - start_time))
   #time_CertsCheck  = certsCheck(path)
   #print('[+] CertsCheck took: %0.2f seconds' % ( time_DNSCheck - start_time))
   time_DNSCheck  = dnsCheck(path)
   print('[+] DNSCheck took: %0.2f seconds'   % ( time_DNSCheck - start_time))
 except Exception as  err:
   print('[-] Circuit creation error: %s' % path)
 return time.time() - start_time
def certsCheck(path):
   """
   SSL Strip detection
   TODO: It's still a weak control. Need to collect and to compare public_key()
   """
   print('[+] Checking Certificates')
   try:
       socks.setdefaultproxy(socks.PROXY_TYPE_SOCKS5, "127.0.0.1", 9050)
       socket.socket = socks.socket
       for url in ssl_strip_monitored_urls:
           cert = ssl.get_server_certificate((str(url), 443))
           x509 = OpenSSL.crypto.load_certificate(OpenSSL.crypto.FILETYPE_PEM, cert)
           p_k  = x509.get_pubkey()
           s_n  = x509.get_serial_number()
           for stored_cert in check_ssl_strip_results:
               if str(url) == str(stored_cert.domain):
                   if str(stored_cert.serial_number) != str(s_n):
                       print('[+] ALERT Found SSL Strip on uri (%s) through path %s ' % (url, path))
                       break
                   else:
                       print('[+] Certificate Check seems to be OK for %s' % url)
   except Exception as err:
       print('[-] Error: %s' % err)
       traceback.print_exc()
   socket.close()
   return time.time()
def dnsCheck(path):
   """
   DNS Poisoning Check
   """
   try:
       socks.setdefaultproxy(socks.PROXY_TYPE_SOCKS5, "127.0.0.1", 9050)
       socket.socket = socks.socket
       print('[+] Checking DNS ')
       for domain in domains:
           ipv4 = socket.gethostbyname(domain)
           for p_d in check_domain_poison_results:
               if str(p_d.domain) == str(domain):
                   found = False
                   for d_ip in p_d.address:
                       if str(ipv4) == str(d_ip):
                           found = True
                           break
                   if found == False:
                       print('[+] ALERT:DNS SPOOFING FOUND: name: %s ip: %s  (path: %s )' % (domain, ipv4, path) )
                   else:
                       print('[+] Check DNS (%s) seems to be OK' % domain)
   except Exception as err:
       print('[-] Error: %s' % err)
       traceback.print_exc()
   socket.close()
   return time.time()
def fileCheck(path):
   """
   Downloading file through TOR circuits doing the hashing
   """
   print('[+] Checking For File patching ')
   for url in check_files:
       try:
           #File Rereive
           data = query(url)
           file_name = url.split("/")[-1]
           _,tmp_file = tempfile.mkstemp(prefix="exitmap_%s_" % file_name)
           with open(tmp_file, "wb") as fd:
               fd.write(data)
               for i in check_files_patch_results:
                   if str(i.url) == str(url):
                       if str(i.filehash) != str(sha512_file(tmp_file)):
                           print('[+] ALERT File Patch FOUND !')
                           print('    | exitnode : %s' % str(i.exitnode)      )
                           print('    |_________> url: %s' % str(i.url)        )
                           print('    |_________> filePath: %s' % str(i.filepath)   )
                           print('    |_________> fileHash: %s' % str(i.filehash)   )
                           #check_files_patch_results.append( File_Check_Results(url, file_name, tmp_file, path, sha512_file(tmp_file)) )
                       else :
                           print('[+] File (%s) seems to be ok' % i.url)
                       break
       except Exception as err:
               print('[-] Error ! %s' % err)
               traceback.print_exc()
               pass
   return time.time()
def sha512_file(file_name):
   """
   Calculate SHA512 over the given file.
   """
   hash_func = hashlib.sha256()
   with open(file_name, "rb") as fd:
       hash_func.update(fd.read())
   return hash_func.hexdigest()
if __name__ == '__main__':
   start_analysis = time.time()
   print("""
 |=====================================================================|
 | Find Malicious Relay Nodes is a python script made for checking 3   |
 | unique kind of frauds such as:                                      |
 | (1) File Patching                                                   |
 | (2) DNS Poison                                                      |
 | (3) SSL Stripping (MITM SSL)                                        |
 |=====================================================================|
        """)
   print("""
 |=====================================================================|
 |                 Initialization Phase                                |
 |=====================================================================|
      """)
   dns_setup_time             = resolveOriginalDomains()
   print('[+] DNS Setup Finished: %0.2f' % (dns_setup_time - start_analysis))
   file_check_original_time   = fileCheckOriginal()
   print('[+] File Setup Finished: %0.2f' % (file_check_original_time - start_analysis))
   ssl_checking_original_time = sslCheckOriginal()
   print('[+] Acquiring Certificates  Setup Finished: %0.2f' % (ssl_checking_original_time - start_analysis))
   print("""
 |=====================================================================|
 |                 Analysis  Phase                                     |
 |=====================================================================|
         """)
   print('[+] Connecting and Fetching possible Relays ...')
   with stem.control.Controller.from_port() as controller:
     controller.authenticate()
     net_status = controller.get_network_statuses()
     for descriptor in net_status:
       try:
         fingerprint = descriptor.fingerprint
         print('[+] Selecting a New Exit Point:')
         print('[+] |_________> FingerPrint: %s ' % fingerprint)
         print('[+] |_________> Flags: %s ' % descriptor.flags)
         print('[+] |_________> Exit_Policies: %s ' % descriptor.exit_policy)
         if 'EXIT' in (flag.upper() for flag in descriptor.flags):
             print('[+] Found Exit Point. Performing Scan through EXIT: %s' % fingerprint)
             if None == descriptor.exit_policy:
                 print('[+] No Exit Policies found ... no certs checking')
                 time_taken = scan(controller, [TRUSTED_HOP_FINGERPRINT, fingerprint])
         else:
             #print('[+] Not Exit Point found. Using it as Relay passing to TRUST Exit Point')
             pass
             #time_taken = scan(controller, [fingerprint, TRUSTED_HOP_FINGERPRINT])
         #print('[+] Finished Analysis for %s finished  => %0.2f seconds' % (fingerprint, time_taken))
       except Exception as exc:
           print('[-] Exception on  FingerPrint: %s => %s' % (fingerprint, exc))
           traceback.print_exc()
           pass

转载于:https://blog.51cto.com/cxnic/1727685