BaseAttack_BACKUP_2866.py 24 KB

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  1. import socket
  2. import sys
  3. import ipaddress
  4. import os
  5. import random
  6. import re
  7. import tempfile
  8. from abc import abstractmethod, ABCMeta
  9. from scapy.layers.inet import Ether
  10. import numpy as np
  11. import ID2TLib.libpcapreader as pr
  12. from scapy.utils import PcapWriter
  13. from Attack import AttackParameters
  14. from Attack.AttackParameters import Parameter
  15. from Attack.AttackParameters import ParameterTypes
  16. class BaseAttack(metaclass=ABCMeta):
  17. """
  18. Abstract base class for all attack classes. Provides basic functionalities, like parameter validation.
  19. """
  20. def __init__(self, name, description, attack_type):
  21. """
  22. To be called within the individual attack class to initialize the required parameters.
  23. :param statistics: A reference to the Statistics class.
  24. :param name: The name of the attack class.
  25. :param description: A short description of the attack.
  26. :param attack_type: The type the attack belongs to, like probing/scanning, malware.
  27. """
  28. # Reference to statistics class
  29. self.statistics = None
  30. # Class fields
  31. self.attack_name = name
  32. self.attack_description = description
  33. self.attack_type = attack_type
  34. self.params = {}
  35. self.supported_params = {}
  36. self.attack_start_utime = 0
  37. self.attack_end_utime = 0
  38. def set_statistics(self, statistics):
  39. """
  40. Specify the statistics object that will be used to calculate the parameters of this attack.
  41. <<<<<<< HEAD
  42. The statistics are used to calculate default parameters and to process user supplied
  43. =======
  44. The statistics are used to calculate default parameters and to process user supplied
  45. >>>>>>> 48c729f6dbfeb1e2670c762729090a48d5f0b490
  46. queries.
  47. :param statistics: Reference to a statistics object.
  48. """
  49. self.statistics = statistics
  50. @abstractmethod
  51. def init_params(self):
  52. """
  53. Initialize all required parameters taking into account user supplied values. If no value is supplied,
  54. or if a user defined query is supplied, use a statistics object to do the calculations.
  55. A call to this function requires a call to 'set_statistics' first.
  56. """
  57. pass
  58. @abstractmethod
  59. def generate_attack_pcap(self):
  60. """
  61. Creates a pcap containing the attack packets.
  62. :return: The location of the generated pcap file.
  63. """
  64. pass
  65. ################################################
  66. # HELPER VALIDATION METHODS
  67. # Used to validate the given parameter values
  68. ################################################
  69. @staticmethod
  70. def _is_mac_address(mac_address: str):
  71. """
  72. Verifies if the given string is a valid MAC address. Accepts the formats 00:80:41:ae:fd:7e and 00-80-41-ae-fd-7e.
  73. :param mac_address: The MAC address as string.
  74. :return: True if the MAC address is valid, otherwise False.
  75. """
  76. pattern = re.compile('^([0-9A-Fa-f]{2}[:-]){5}([0-9A-Fa-f]{2})$', re.MULTILINE)
  77. if isinstance(mac_address, list):
  78. for mac in mac_address:
  79. if re.match(pattern, mac) is None:
  80. return False
  81. else:
  82. if re.match(pattern, mac_address) is None:
  83. return False
  84. return True
  85. @staticmethod
  86. def _is_ip_address(ip_address: str):
  87. """
  88. Verifies that the given string or list of IP addresses (strings) is a valid IPv4/IPv6 address.
  89. Accepts comma-separated lists of IP addresses, like "192.169.178.1, 192.168.178.2"
  90. :param ip_address: The IP address(es) as list of strings or comma-separated string.
  91. :return: True if all IP addresses are valid, otherwise False. And a list of IP addresses as string.
  92. """
  93. ip_address_output = []
  94. # a comma-separated list of IP addresses must be splitted first
  95. if isinstance(ip_address, str):
  96. ip_address = ip_address.split(',')
  97. for ip in ip_address:
  98. try:
  99. ipaddress.ip_address(ip)
  100. ip_address_output.append(ip)
  101. except ValueError:
  102. return False, ip_address_output
  103. if len(ip_address_output) == 1:
  104. return True, ip_address_output[0]
  105. else:
  106. return True, ip_address_output
  107. @staticmethod
  108. def _is_port(ports_input: str):
  109. """
  110. Verifies if the given value is a valid port. Accepts port ranges, like 80-90, 80..99, 80...99.
  111. :param ports_input: The port number as int or string.
  112. :return: True if the port number is valid, otherwise False. If a single port or a comma-separated list of ports
  113. was given, a list of int is returned. If a port range was given, the range is resolved
  114. and a list of int is returned.
  115. """
  116. def _is_invalid_port(num):
  117. """
  118. Checks whether the port number is invalid.
  119. :param num: The port number as int.
  120. :return: True if the port number is invalid, otherwise False.
  121. """
  122. return num < 1 or num > 65535
  123. if isinstance(ports_input, str):
  124. ports_input = ports_input.replace(' ', '').split(',')
  125. elif isinstance(ports_input, int):
  126. ports_input = [ports_input]
  127. ports_output = []
  128. for port_entry in ports_input:
  129. if isinstance(port_entry, int):
  130. if _is_invalid_port(port_entry):
  131. return False
  132. ports_output.append(port_entry)
  133. elif isinstance(port_entry, str) and port_entry.isdigit():
  134. # port_entry describes a single port
  135. port_entry = int(port_entry)
  136. if _is_invalid_port(port_entry):
  137. return False
  138. ports_output.append(port_entry)
  139. elif '-' in port_entry or '..' in port_entry:
  140. # port_entry describes a port range
  141. # allowed format: '1-49151', '1..49151', '1...49151'
  142. match = re.match('^([0-9]{1,5})(?:-|\.{2,3})([0-9]{1,5})$', port_entry)
  143. # check validity of port range
  144. # and create list of ports derived from given start and end port
  145. (port_start, port_end) = int(match.group(1)), int(match.group(2))
  146. if _is_invalid_port(port_start) or _is_invalid_port(port_end):
  147. return False
  148. else:
  149. ports_list = [i for i in range(port_start, port_end + 1)]
  150. # append ports at ports_output list
  151. ports_output += ports_list
  152. if len(ports_output) == 1:
  153. return True, ports_output[0]
  154. else:
  155. return True, ports_output
  156. @staticmethod
  157. def _is_timestamp(timestamp: str):
  158. """
  159. Checks whether the given value is in a valid timestamp format. The accepted format is:
  160. YYYY-MM-DD h:m:s, whereas h, m, s may be one or two digits.
  161. :param timestamp: The timestamp to be checked.
  162. :return: True if the timestamp is valid, otherwise False.
  163. """
  164. is_valid = re.match('[0-9]{4}(?:-[0-9]{1,2}){2} (?:[0-9]{1,2}:){2}[0-9]{1,2}', timestamp)
  165. return is_valid is not None
  166. @staticmethod
  167. def _is_boolean(value):
  168. """
  169. Checks whether the given value (string or bool) is a boolean. Strings are valid booleans if they are in:
  170. {y, yes, t, true, on, 1, n, no, f, false, off, 0}.
  171. :param value: The value to be checked.
  172. :return: True if the value is a boolean, otherwise false. And the casted boolean.
  173. """
  174. # If value is already a boolean
  175. if isinstance(value, bool):
  176. return True, value
  177. # If value is a string
  178. # True values are y, yes, t, true, on and 1;
  179. # False values are n, no, f, false, off and 0.
  180. # Raises ValueError if value is anything else.
  181. try:
  182. import distutils.core
  183. value = distutils.util.strtobool(value.lower())
  184. is_bool = True
  185. except ValueError:
  186. is_bool = False
  187. return is_bool, value
  188. @staticmethod
  189. def _is_float(value):
  190. """
  191. Checks whether the given value is a float.
  192. :param value: The value to be checked.
  193. :return: True if the value is a float, otherwise False. And the casted float.
  194. """
  195. try:
  196. value = float(value)
  197. return True, value
  198. except ValueError:
  199. return False, value
  200. # Aidmar
  201. @staticmethod
  202. def _is_domain(val: str):
  203. """
  204. Verifies that the given string is a valid URI.
  205. :param uri: The URI as string.
  206. :return: True if URI is valid, otherwise False.
  207. """
  208. domain = re.match('^(?:[a-zA-Z]|[0-9]|[$-_@.&+]|[!*\(\),]|(?:%[0-9a-fA-F][0-9a-fA-F]))+$', val)
  209. return (domain is not None)
  210. #########################################
  211. # HELPER METHODS
  212. #########################################
  213. def add_param_value(self, param, value):
  214. """
  215. Adds the pair param : value to the dictionary of attack parameters. Prints and error message and skips the
  216. parameter if the validation fails.
  217. :param stats: Statistics used to calculate user queries or default values.
  218. :param param: Name of the parameter that we wish to modify.
  219. :param value: The value we wish to assign to the specifried parameter.
  220. :return: None.
  221. """
  222. # This function call is valid only if there is a statistics object available.
  223. if self.statistics is None:
  224. print('Error: Attack parameter added without setting a statistics object first.')
  225. exit(1)
  226. # by default no param is valid
  227. is_valid = False
  228. # get AttackParameters instance associated with param
  229. # for default values assigned in attack classes, like Parameter.PORT_OPEN
  230. if isinstance(param, AttackParameters.Parameter):
  231. param_name = param
  232. # for values given by user input, like port.open
  233. else:
  234. # Get Enum key of given string identifier
  235. param_name = AttackParameters.Parameter(param)
  236. # Get parameter type of attack's required_params
  237. param_type = self.supported_params.get(param_name)
  238. # Verify validity of given value with respect to parameter type
  239. if param_type is None:
  240. print('Parameter ' + str(param_name) + ' not available for chosen attack. Skipping parameter.')
  241. # If value is query -> get value from database
  242. elif self.statistics.is_query(value):
  243. value = self.statistics.process_db_query(value, False)
  244. if value is not None and value is not "":
  245. is_valid = True
  246. else:
  247. print('Error in given parameter value: ' + value + '. Data could not be retrieved.')
  248. # Validate parameter depending on parameter's type
  249. elif param_type == ParameterTypes.TYPE_IP_ADDRESS:
  250. is_valid, value = self._is_ip_address(value)
  251. elif param_type == ParameterTypes.TYPE_PORT:
  252. is_valid, value = self._is_port(value)
  253. elif param_type == ParameterTypes.TYPE_MAC_ADDRESS:
  254. is_valid = self._is_mac_address(value)
  255. elif param_type == ParameterTypes.TYPE_INTEGER_POSITIVE:
  256. if isinstance(value, int) and int(value) >= 0:
  257. is_valid = True
  258. elif isinstance(value, str) and value.isdigit() and int(value) >= 0:
  259. is_valid = True
  260. value = int(value)
  261. elif param_type == ParameterTypes.TYPE_FLOAT:
  262. is_valid, value = self._is_float(value)
  263. # this is required to avoid that the timestamp's microseconds of the first attack packet is '000000'
  264. # but microseconds are only chosen randomly if the given parameter does not already specify it
  265. # e.g. inject.at-timestamp=123456.987654 -> is not changed
  266. # e.g. inject.at-timestamp=123456 -> is changed to: 123456.[random digits]
  267. if param_name == Parameter.INJECT_AT_TIMESTAMP and is_valid and ((value - int(value)) == 0):
  268. value = value + random.uniform(0, 0.999999)
  269. elif param_type == ParameterTypes.TYPE_TIMESTAMP:
  270. is_valid = self._is_timestamp(value)
  271. elif param_type == ParameterTypes.TYPE_BOOLEAN:
  272. is_valid, value = self._is_boolean(value)
  273. elif param_type == ParameterTypes.TYPE_PACKET_POSITION:
  274. ts = pr.pcap_processor(self.statistics.pcap_filepath, "False").get_timestamp_mu_sec(int(value))
  275. if 0 <= int(value) <= self.statistics.get_packet_count() and ts >= 0:
  276. is_valid = True
  277. param_name = Parameter.INJECT_AT_TIMESTAMP
  278. value = (ts / 1000000) # convert microseconds from getTimestampMuSec into seconds
  279. # Aidmar
  280. elif param_type == ParameterTypes.TYPE_DOMAIN:
  281. is_valid = self._is_domain(value)
  282. # add value iff validation was successful
  283. if is_valid:
  284. self.params[param_name] = value
  285. else:
  286. print("ERROR: Parameter " + str(param) + " or parameter value " + str(value) +
  287. " not valid. Skipping parameter.")
  288. def get_param_value(self, param: Parameter):
  289. """
  290. Returns the parameter value for a given parameter.
  291. :param param: The parameter whose value is wanted.
  292. :return: The parameter's value.
  293. """
  294. return self.params.get(param)
  295. def check_parameters(self):
  296. """
  297. Checks whether all parameter values are defined. If a value is not defined, the application is terminated.
  298. However, this should not happen as all attack should define default parameter values.
  299. """
  300. # parameters which do not require default values
  301. non_obligatory_params = [Parameter.INJECT_AFTER_PACKET, Parameter.NUMBER_ATTACKERS]
  302. for param, type in self.supported_params.items():
  303. # checks whether all params have assigned values, INJECT_AFTER_PACKET must not be considered because the
  304. # timestamp derived from it is set to Parameter.INJECT_AT_TIMESTAMP
  305. if param not in self.params.keys() and param not in non_obligatory_params:
  306. print("\033[91mCRITICAL ERROR: Attack '" + self.attack_name + "' does not define the parameter '" +
  307. str(param) + "'.\n The attack must define default values for all parameters."
  308. + "\n Cannot continue attack generation.\033[0m")
  309. import sys
  310. sys.exit(0)
  311. def write_attack_pcap(self, packets: list, append_flag: bool = False, destination_path: str = None):
  312. """
  313. Writes the attack's packets into a PCAP file with a temporary filename.
  314. :return: The path of the written PCAP file.
  315. """
  316. # Only check params initially when attack generation starts
  317. if append_flag is False and destination_path is None:
  318. # Check if all req. parameters are set
  319. self.check_parameters()
  320. # Determine destination path
  321. if destination_path is not None and os.path.exists(destination_path):
  322. destination = destination_path
  323. else:
  324. temp_file = tempfile.NamedTemporaryFile(delete=False, suffix='.pcap')
  325. destination = temp_file.name
  326. # Write packets into pcap file
  327. pktdump = PcapWriter(destination, append=append_flag)
  328. pktdump.write(packets)
  329. # Store pcap path and close file objects
  330. pktdump.close()
  331. return destination
  332. #########################################
  333. # RANDOM IP/MAC ADDRESS GENERATORS
  334. #########################################
  335. @staticmethod
  336. def generate_random_ipv4_address(ipClass, n: int = 1):
  337. """
  338. Generates n random IPv4 addresses.
  339. :param n: The number of IP addresses to be generated
  340. :return: A single IP address, or if n>1, a list of IP addresses
  341. """
  342. def is_invalid(ipAddress: ipaddress.IPv4Address):
  343. return ipAddress.is_multicast or ipAddress.is_unspecified or ipAddress.is_loopback or \
  344. ipAddress.is_link_local or ipAddress.is_reserved or ipAddress.is_private
  345. # Aidmar - generate a random IP from specific class
  346. def generate_address(ipClass):
  347. if ipClass == "Unknown":
  348. return ipaddress.IPv4Address(random.randint(0, 2 ** 32 - 1))
  349. else:
  350. # For DDoS attack, we do not generate private IPs
  351. if "private" in ipClass:
  352. ipClass = ipClass[0] # convert A-private to A
  353. ipClassesByte1 = {"A": {1,126}, "B": {128,191}, "C":{192, 223}, "D":{224, 239}, "E":{240, 254}}
  354. temp = list(ipClassesByte1[ipClass])
  355. minB1 = temp[0]
  356. maxB1 = temp[1]
  357. b1 = random.randint(minB1, maxB1)
  358. b2 = random.randint(1, 255)
  359. b3 = random.randint(1, 255)
  360. b4 = random.randint(1, 255)
  361. ipAddress = ipaddress.IPv4Address(str(b1) +"."+ str(b2) + "." + str(b3) + "." + str(b4))
  362. return ipAddress
  363. ip_addresses = []
  364. for i in range(0, n):
  365. address = generate_address(ipClass)
  366. while is_invalid(address):
  367. address = generate_address(ipClass)
  368. ip_addresses.append(str(address))
  369. if n == 1:
  370. return ip_addresses[0]
  371. else:
  372. return ip_addresses
  373. @staticmethod
  374. def generate_random_ipv6_address(n: int = 1):
  375. """
  376. Generates n random IPv6 addresses.
  377. :param n: The number of IP addresses to be generated
  378. :return: A single IP address, or if n>1, a list of IP addresses
  379. """
  380. def is_invalid(ipAddress: ipaddress.IPv6Address):
  381. return ipAddress.is_multicast or ipAddress.is_unspecified or ipAddress.is_loopback or \
  382. ipAddress.is_link_local or ipAddress.is_private or ipAddress.is_reserved
  383. def generate_address():
  384. return ipaddress.IPv6Address(random.randint(0, 2 ** 128 - 1))
  385. ip_addresses = []
  386. for i in range(0, n):
  387. address = generate_address()
  388. while is_invalid(address):
  389. address = generate_address()
  390. ip_addresses.append(str(address))
  391. if n == 1:
  392. return ip_addresses[0]
  393. else:
  394. return ip_addresses
  395. @staticmethod
  396. def generate_random_mac_address(n: int = 1):
  397. """
  398. Generates n random MAC addresses.
  399. :param n: The number of MAC addresses to be generated.
  400. :return: A single MAC addres, or if n>1, a list of MAC addresses
  401. """
  402. def is_invalid(address: str):
  403. first_octet = int(address[0:2], 16)
  404. is_multicast_address = bool(first_octet & 0b01)
  405. is_locally_administered = bool(first_octet & 0b10)
  406. return is_multicast_address or is_locally_administered
  407. def generate_address():
  408. mac = [random.randint(0x00, 0xff) for i in range(0, 6)]
  409. return ':'.join(map(lambda x: "%02x" % x, mac))
  410. mac_addresses = []
  411. for i in range(0, n):
  412. address = generate_address()
  413. while is_invalid(address):
  414. address = generate_address()
  415. mac_addresses.append(address)
  416. if n == 1:
  417. return mac_addresses[0]
  418. else:
  419. return mac_addresses
  420. # Aidmar
  421. def get_reply_delay(self, ip_dst):
  422. """
  423. Gets the minimum and the maximum reply delay for all the connections of a specific IP.
  424. :param ip_dst: The IP to reterive its reply delay.
  425. :return minDelay: minimum delay
  426. :return maxDelay: maximum delay
  427. """
  428. result = self.statistics.process_db_query(
  429. "SELECT AVG(minDelay), AVG(maxDelay) FROM conv_statistics WHERE ipAddressB='6.6.6.6';") #" + ip_dst + "';")
  430. if result[0][0] and result[0][1]:
  431. minDelay = result[0][0]
  432. maxDelay = result[0][1]
  433. else:
  434. allMinDelays = self.statistics.process_db_query("SELECT minDelay FROM conv_statistics LIMIT 500;")
  435. minDelay = np.median(allMinDelays)
  436. allMaxDelays = self.statistics.process_db_query("SELECT maxDelay FROM conv_statistics LIMIT 500;")
  437. maxDelay = np.median(allMaxDelays)
  438. minDelay = int(minDelay) * 10 ** -6 # convert from micro to seconds
  439. maxDelay = int(maxDelay) * 10 ** -6
  440. return minDelay, maxDelay
  441. # Group the packets in conversations
  442. def packetsToConvs(self,exploit_raw_packets):
  443. """
  444. Classifies a bunch of packets to conversations groups. A conversation is a set of packets go between host A (IP,port)
  445. to host B (IP,port)
  446. :param exploit_raw_packets: A set of packets contains several conversations.
  447. :return conversations: A set of arrays, each array contains the packet of specifc conversation
  448. :return orderList_conversations: An array contains the conversations ids (IP_A,port_A, IP_b,port_B) in the order
  449. they appeared in the original packets.
  450. """
  451. conversations = {}
  452. orderList_conversations = []
  453. for pkt_num, pkt in enumerate(exploit_raw_packets):
  454. eth_frame = Ether(pkt[0])
  455. ip_pkt = eth_frame.payload
  456. ip_dst = ip_pkt.getfieldval("dst")
  457. ip_src = ip_pkt.getfieldval("src")
  458. tcp_pkt = ip_pkt.payload
  459. port_dst = tcp_pkt.getfieldval("dport")
  460. port_src = tcp_pkt.getfieldval("sport")
  461. conv_req = (ip_src, port_src, ip_dst, port_dst)
  462. conv_rep = (ip_dst, port_dst, ip_src, port_src)
  463. if conv_req not in conversations and conv_rep not in conversations:
  464. pktList = [pkt]
  465. conversations[conv_req] = pktList
  466. # Order list of conv
  467. orderList_conversations.append(conv_req)
  468. else:
  469. if conv_req in conversations:
  470. pktList = conversations[conv_req]
  471. pktList.append(pkt)
  472. conversations[conv_req] = pktList
  473. else:
  474. pktList = conversations[conv_rep]
  475. pktList.append(pkt)
  476. conversations[conv_rep] = pktList
  477. return (conversations, orderList_conversations)
  478. def is_valid_ip_address(self,addr):
  479. """
  480. Checks if the IP address family is supported.
  481. :param addr: IP address to be checked.
  482. :return: Boolean
  483. """
  484. try:
  485. socket.inet_aton(addr)
  486. return True
  487. except socket.error:
  488. return False
  489. def ip_src_dst_equal_check(self, ip_source, ip_destination):
  490. """
  491. Checks if the source IP and destination IP are equal.
  492. :param ip_source: source IP address.
  493. :param ip_destination: destination IP address.
  494. """
  495. equal = False
  496. if isinstance(ip_source, list):
  497. if ip_destination in ip_source:
  498. equal = True
  499. else:
  500. if ip_source == ip_destination:
  501. equal = True
  502. if equal:
  503. print("\nERROR: Invalid IP addresses; source IP is the same as destination IP: " + ip_source + ".")
  504. sys.exit(0)
  505. def get_inter_arrival_time_dist(self, packets):
  506. timeSteps = []
  507. prvsPktTime = 0
  508. for index, pkt in enumerate(packets):
  509. eth_frame = Ether(pkt[0])
  510. if index == 0:
  511. prvsPktTime = eth_frame.time
  512. else:
  513. timeSteps.append(eth_frame.time - prvsPktTime)
  514. prvsPktTime = eth_frame.time
  515. import numpy as np
  516. freq,values = np.histogram(timeSteps,bins=20)
  517. dict = {}
  518. for i,val in enumerate(values):
  519. if i < len(freq):
  520. dict[str(val)] = freq[i]
  521. return dict
  522. def clean_white_spaces(self, str):
  523. str = str.replace("\\n", "\n")
  524. str = str.replace("\\r", "\r")
  525. str = str.replace("\\t", "\t")
  526. str = str.replace("\\\'", "\'")
  527. return str
  528. def modify_payload(self,str_tcp_seg, orig_target_uri, target_uri, orig_ip_dst, target_host):
  529. if len(str_tcp_seg) > 0:
  530. # convert payload bytes to str => str = "b'..\\r\\n..'"
  531. str_tcp_seg = str_tcp_seg[2:-1]
  532. str_tcp_seg = str_tcp_seg.replace(orig_target_uri, target_uri)
  533. str_tcp_seg = str_tcp_seg.replace(orig_ip_dst, target_host)
  534. str_tcp_seg = self.clean_white_spaces(str_tcp_seg)
  535. return str_tcp_seg