Moving Tshark logic into /tools/tshark.py

Added tests for analyzing handshakes
This commit is contained in:
derv82
2018-04-01 00:37:28 -04:00
parent acc8e296d5
commit a2dbf4c382
2 changed files with 177 additions and 146 deletions

View File

@@ -3,9 +3,9 @@
from ..util.process import Process
from ..util.color import Color
from ..tools.tshark import Tshark
import re
import os
import re, os
class Handshake(object):
def __init__(self, capfile, bssid=None, essid=None):
@@ -18,15 +18,15 @@ class Handshake(object):
Tries to find BSSID and ESSID from cap file.
Sets this instances 'bssid' and 'essid' instance fields.
'''
# Get list of bssid/essid pairs from cap file
pairs = self.tshark_bssid_essid_pairs()
pairs = Tshark.bssid_essid_pairs(self.capfile, bssid=self.bssid)
if len(pairs) == 0:
# Find bssid/essid pairs that have handshakes in Pyrit
pairs = self.pyrit_handshakes()
pairs = self.pyrit_handshakes() # Find bssid/essid pairs that have handshakes in Pyrit
if len(pairs) == 0 and not self.bssid and not self.essid:
# Tshark and Pyrit failed us, nothing else we can do.
raise Exception("Cannot find BSSID or ESSID in cap file")
raise Exception("Cannot find BSSID or ESSID in cap file") # Tshark and Pyrit failed us, nothing else we can do.
if not self.essid and not self.bssid:
# We do not know the bssid nor the essid
@@ -34,10 +34,8 @@ class Handshake(object):
# HACK: Just use the first one we see
self.bssid = pairs[0][0]
self.essid = pairs[0][1]
Color.pl('{!} {O}Warning{W}:' +
' {O}Arbitrarily selected' +
' {R}bssid{O} {C}%s{O} and {R}essid{O} "{C}%s{O}"{W}'
% (self.bssid, self.essid))
Color.pl('{!} {O}Warning{W}: {O}Arbitrarily selected ' +
'{R}bssid{O} {C}%s{O} and {R}essid{O} "{C}%s{O}"{W}' % (self.bssid, self.essid))
elif not self.bssid:
# We already know essid
@@ -59,140 +57,23 @@ class Handshake(object):
if not self.bssid or not self.essid:
self.divine_bssid_and_essid()
if len(self.tshark_handshakes()) > 0:
return True
if len(self.tshark_handshakes()) > 0: return True
if len(self.pyrit_handshakes()) > 0: return True
if len(self.pyrit_handshakes()) > 0:
return True
if len(self.cowpatty_handshakes()) > 0:
return True
if len(self.aircrack_handshakes()) > 0:
return True
# TODO: Can we trust cowpatty & aircrack?
#if len(self.cowpatty_handshakes()) > 0: return True
#if len(self.aircrack_handshakes()) > 0: return True
return False
def tshark_bssid_essid_pairs(self):
'''
Scrapes capfile for beacon frames indicating the ESSID.
Returns list of tuples: (bssid,essid)
'''
if not Process.exists('tshark'):
return []
essids = set()
# Extract beacon frames from cap file
cmd = [
'tshark',
'-r', self.capfile,
'-R', 'wlan.fc.type_subtype == 0x08 || wlan.fc.type_subtype == 0x05',
'-2', # tshark: -R without -2 is deprecated.
'-n'
]
proc = Process(cmd, devnull=False)
for line in proc.stdout().split('\n'):
# Extract src, dst, and essid
mac_regex = ('[a-zA-Z0-9]{2}:' * 6)[:-1]
match = re.search('(%s) [^ ]* (%s).*.*SSID=(.*)$'
% (mac_regex, mac_regex), line)
if match is None:
# Line doesn't contain src, dst, ssid
continue
(src, dst, essid) = match.groups()
if dst.lower() == "ff:ff:ff:ff:ff:ff": continue
if self.bssid:
# We know the BSSID, only return the ESSID for this BSSID.
if self.bssid.lower() == src.lower() or self.bssid.lower() == dst.lower():
essids.add((src, essid))
else:
# We do not know BSSID, add it.
essids.add((src, essid))
# Return list of tuples
return [x for x in essids]
def tshark_command(self):
return [
'tshark',
'-r', self.capfile,
'-R', 'eapol',
'-n',
'-2' # 2-pass filtering, required when using -R in newer versions of tshark
]
'''Returns list of tuples: (bssid,essid) found in capfile'''
def tshark_handshakes(self):
''' Returns True if tshark identifies a handshake, False otherwise '''
if not Process.exists('tshark'):
return []
target_client_msg_nums = {}
# Dump EAPOL packets
proc = Process(self.tshark_command(), devnull=False)
for line in proc.stdout().split('\n'):
# Extract source mac, destination mac, and message numbers
mac_regex = ('[a-zA-Z0-9]{2}:' * 6)[:-1]
match = re.search('(%s) (?:->|→) (%s).*Message.*(\d).*(\d)'
% (mac_regex, mac_regex), line)
if match is None:
# Line doesn't contain src, dst, Message numbers
continue
(src, dst, index, ttl) = match.groups()
# "Message (index) of (ttl)"
index = int(index)
ttl = int(ttl)
if ttl != 4:
# Must be a 4-way handshake
continue
# Identify the client and target MAC addresses
if index % 2 == 1:
# First and Third messages
target = src
client = dst
else:
# Second and Fourth messages
client = src
target = dst
if self.bssid and self.bssid.lower() != target.lower():
# We know the BSSID and this msg was not for the target
continue
target_client_key = '%s,%s' % (target, client)
# Ensure all 4 messages are:
# Between the same client and target
# In numeric & chronological order (1,2,3,4)
if index == 1:
# First message, add to dict
target_client_msg_nums[target_client_key] = 1
elif target_client_key not in target_client_msg_nums:
# Not first message, we haven't gotten the first message yet
continue
elif index - 1 != target_client_msg_nums[target_client_key]:
# Message is not in sequence
continue
else:
# Message is > 1 and is received in-order
target_client_msg_nums[target_client_key] = index
bssids = set()
# Check if we have all 4 messages for the handshake between the same MACs
for (client_target, num) in target_client_msg_nums.items():
if num == 4:
# We got a handshake!
bssid = client_target.split(',')[0]
bssids.add(bssid)
return [(bssid, None) for bssid in bssids]
tshark_bssids = Tshark.bssids_with_handshakes(self.capfile, bssid=self.bssid)
return [(bssid, None) for bssid in tshark_bssids]
def cowpatty_command(self):
@@ -259,8 +140,7 @@ class Handshake(object):
current_essid = essid
hit_target = True
else:
# This AccessPoint is not what we're looking for
hit_Target = False
hit_Target = False # This AccessPoint is not what we're looking for
else:
# Line does not contain AccessPoint
if hit_target and ', good' in line:
@@ -268,19 +148,22 @@ class Handshake(object):
return [x for x in bssid_essid_pairs]
def aircrack_command(self):
return 'echo "" | aircrack-ng -a 2 -w - -b %s "%s"' % (self.bssid, self.capfile)
def aircrack_handshakes(self):
'''Returns tuple (BSSID,None) if aircrack thinks self.capfile contains a handshake / can be cracked'''
if not self.bssid:
return []
(stdout, stderr) = Process.call(self.aircrack_command())
return [] # Aircrack requires BSSID
command = 'echo "" | aircrack-ng -a 2 -w - -b %s "%s"' % (self.bssid, self.capfile)
(stdout, stderr) = Process.call(command)
if 'passphrase not in dictionary' in stdout.lower():
return [(self.bssid, None)]
else:
return []
def analyze(self):
'''Prints analysis of handshake capfile'''
self.divine_bssid_and_essid()
pairs = self.tshark_handshakes()
@@ -314,8 +197,7 @@ class Handshake(object):
cmd = [
'tshark',
'-r', self.capfile, # input file
'-R', 'wlan.fc.type_subtype == 0x08 || wlan.fc.type_subtype == 0x05 || eapol', # filter
'-2', # tshark: -R without -2 is deprecated.
'-Y', 'wlan.fc.type_subtype == 0x08 || wlan.fc.type_subtype == 0x05 || eapol', # filter
'-w', outfile # output file
]
proc = Process(cmd)
@@ -357,7 +239,23 @@ class Handshake(object):
if __name__ == '__main__':
hs = Handshake('./tests/files/handshake_exists.cap', bssid='A4:2B:8C:16:6B:3A')
print('With BSSID & ESSID specified:')
hs = Handshake('./tests/files/handshake_has_1234.cap', bssid='18:d6:c7:6d:6b:18', essid='YZWifi')
hs.analyze()
print("has_hanshake() =", hs.has_handshake())
print('\nWith BSSID, but no ESSID specified:')
hs = Handshake('./tests/files/handshake_has_1234.cap', bssid='18:d6:c7:6d:6b:18')
hs.analyze()
print("has_hanshake() =", hs.has_handshake())
print('\nWith ESSID, but no BSSID specified:')
hs = Handshake('./tests/files/handshake_has_1234.cap', essid='YZWifi')
hs.analyze()
print("has_hanshake() =", hs.has_handshake())
print('\nWith neither BSSID nor ESSID specified:')
hs = Handshake('./tests/files/handshake_has_1234.cap')
hs.analyze()
print("has_hanshake() =", hs.has_handshake())

View File

@@ -14,6 +14,136 @@ class Tshark(object):
def exists():
return Process.exists('tshark')
@staticmethod
def _extract_src_dst_index_total(line):
# Extract BSSIDs, handshake # (1-4) and handshake "total" (4)
mac_regex = ('[a-zA-Z0-9]{2}:' * 6)[:-1]
match = re.search('(%s)\s*.*\s*(%s).*Message.*(\d).*of.*(\d)' % (mac_regex, mac_regex), line)
if match is None:
# Line doesn't contain src, dst, Message numbers
return None, None, None, None
(src, dst, index, total) = match.groups()
return src, dst, index, total
@staticmethod
def _build_target_client_handshake_map(output, bssid=None):
# Map of target_ssid,client_ssid -> handshake #s
# E.g. 12:34:56,21:43:65 -> 3
target_client_msg_nums = {}
for line in output.split('\n'):
src, dst, index, total = Tshark._extract_src_dst_index_total(line)
if src is None: continue # Skip
index = int(index)
total = int(total)
if total != 4: continue # Handshake X of 5? X of 3? Skip it.
# Identify the client and target MAC addresses
if index % 2 == 1:
# First and Third messages
target = src
client = dst
else:
# Second and Fourth messages
client = src
target = dst
if bssid is not None and bssid.lower() != target.lower():
# We know the BSSID and this msg was not for the target
continue
target_client_key = '%s,%s' % (target, client)
# Ensure all 4 messages are:
# Between the same client and target (not different clients connecting).
# In numeric & chronological order (Message 1, then 2, then 3, then 4)
if index == 1:
target_client_msg_nums[target_client_key] = 1 # First message
elif target_client_key not in target_client_msg_nums:
continue # Not first message. We haven't gotten the first message yet. Skip.
elif index - 1 != target_client_msg_nums[target_client_key]:
continue # Message is not in sequence. Skip
else:
# Happy case: Message is > 1 and is received in-order
target_client_msg_nums[target_client_key] = index
return target_client_msg_nums
@staticmethod
def bssids_with_handshakes(capfile, bssid=None):
if not Tshark.exists():
return []
# Returns list of BSSIDs for which we have valid handshakes in the capfile.
command = [
'tshark',
'-r', capfile,
'-n', # Don't resolve addresses
'-Y', 'eapol' # Filter for only handshakes
]
tshark = Process(command, devnull=False)
target_client_msg_nums = Tshark._build_target_client_handshake_map(tshark.stdout(), bssid=bssid)
bssids = set()
# Check if we have all 4 messages for the handshake between the same MACs
for (target_client, num) in target_client_msg_nums.items():
if num == 4:
# We got a handshake!
this_bssid = target_client.split(',')[0]
bssids.add(this_bssid)
return list(bssids)
@staticmethod
def bssid_essid_pairs(capfile, bssid):
# Finds all BSSIDs (with corresponding ESSIDs) from cap file.
# Returns list of tuples(BSSID, ESSID)
if not Tshark.exists():
return []
ssid_pairs = set()
command = [
'tshark',
'-r', capfile, # Path to cap file
# Extract beacon frames
'-Y', 'wlan.fc.type_subtype == 0x08 || wlan.fc.type_subtype == 0x05',
'-n', # Don't resolve addresses
]
tshark = Process(command, devnull=False)
for line in tshark.stdout().split('\n'):
# Extract src, dst, and essid
mac_regex = ('[a-zA-Z0-9]{2}:' * 6)[:-1]
match = re.search('(%s) [^ ]* (%s).*.*SSID=(.*)$' % (mac_regex, mac_regex), line)
if match is None:
continue # Line doesn't contain src, dst, ssid
(src, dst, essid) = match.groups()
if dst.lower() == "ff:ff:ff:ff:ff:ff":
continue # Skip broadcast packets
if bssid is not None:
# We know the BSSID, only return the ESSID for this BSSID.
if bssid.lower() == src.lower():
ssid_pairs.add((src, essid)) # This is our BSSID, add it
else:
ssid_pairs.add((src, essid)) # We do not know BSSID, add it.
return list(ssid_pairs)
@staticmethod
def check_for_wps_and_update_targets(capfile, targets):
'''
@@ -66,6 +196,7 @@ if __name__ == '__main__':
test_file = './tests/files/contains_wps_network.cap'
target_bssid = 'A4:2B:8C:16:6B:3A'
'''
from ..model.target import Target
fields = [
'A4:2B:8C:16:6B:3A', # BSSID
@@ -84,4 +215,6 @@ if __name__ == '__main__':
print('Target(BSSID={}).wps = {} (Expected: True)'.format(targets[0].bssid, targets[0].wps))
assert targets[0].wps == True
'''
print(Tshark.bssids_with_handshakes(test_file, bssid=target_bssid))