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mirror of https://github.com/mozilla/cipherscan.git synced 2024-11-05 07:23:42 +01:00
cipherscan/cscan.py
Hubert Kario 88ae052f8e add more probes
since not all servers support the ciphers supported by Firefox 42,
add other configurations to make sure we can find a way to connect
to server, if anything could

also includes much more elaborate and realistic TLSv1.3 Client Hello
(the Xmas tree)
2016-08-27 23:26:56 +02:00

391 lines
13 KiB
Python

# Copyright 2016(c) Hubert Kario
# This work is released under the Mozilla Public License Version 2.0
"""tlslite-ng based server configuration (and bug) scanner."""
from __future__ import print_function
from tlslite.messages import ClientHello, ServerHello, ServerHelloDone, Alert
from tlslite.constants import CipherSuite, \
ExtensionType, AlertLevel
from tlslite.extensions import TLSExtension
import sys
import json
import getopt
import itertools
import copy
from cscan.scanner import Scanner
from cscan.config import Xmas_tree, IE_6, IE_8_Win_XP, \
IE_11_Win_7, IE_11_Win_8_1, Firefox_46, Firefox_42, HugeCipherList, \
VeryCompatible
from cscan.modifiers import no_sni, set_hello_version, set_record_version, \
no_extensions, truncate_ciphers_to_size, append_ciphers_to_size, \
extend_with_ext_to_size, add_empty_ext
def scan_with_config(host, port, conf, hostname, __sentry=None, __cache={}):
"""Connect to server and return set of exchanged messages."""
assert __sentry is None
key = (host, port, conf, hostname)
if key in __cache:
return __cache[key]
scanner = Scanner(conf, host, port, hostname)
ret = scanner.scan()
__cache[key] = ret
if verbose and not json_out:
print(".", end='')
sys.stdout.flush()
return ret
class IE_6_ext_tls_1_0(IE_6):
def __init__(self):
super(IE_6_ext_tls_1_0, self).__init__()
self.modifications += ["TLSv1.0", "ext"]
self.version = (3, 1)
self.record_version = (3, 0)
def __call__(self, hostname):
ret = super(IE_6_ext_tls_1_0, self).__call__(hostname)
ret.ssl2 = False
# filter out SSLv2 ciphersuites
ret.cipher_suites = [i for i in ret.cipher_suites if i <= 0xffff and
i != CipherSuite.
TLS_EMPTY_RENEGOTIATION_INFO_SCSV]
ret.extensions = [TLSExtension(extType=ExtensionType.
renegotiation_info)
.create(bytearray(1))]
return ret
def simple_inspector(result):
"""
Perform simple check to see if connection was successful.
Returns True is connection was successful, server replied with
ServerHello and ServerHelloDone messages, and the cipher selected
was present in ciphers advertised by client, False otherwise
"""
if any(isinstance(x, ServerHelloDone) for x in result):
ch = next((x for x in result if isinstance(x, ClientHello)), None)
sh = next((x for x in result if isinstance(x, ServerHello)), None)
if ch and sh:
if sh.cipher_suite not in ch.cipher_suites:
# FAILURE cipher suite mismatch
return False
return True
# incomplete response or error
return False
def verbose_inspector(desc, result):
"""Describe the connection result in human-readable form."""
ret = "{0}:".format(desc)
if any(isinstance(x, ServerHelloDone) for x in result):
ch = next((x for x in result if isinstance(x, ClientHello)), None)
sh = next((x for x in result if isinstance(x, ServerHello)), None)
if sh and ch:
if sh.cipher_suite not in ch.cipher_suites:
ret += " FAILURE cipher suite mismatch"
return ret
name = CipherSuite.ietfNames[sh.cipher_suite] \
if sh.cipher_suite in CipherSuite.ietfNames \
else hex(sh.cipher_suite)
ret += " ok: {0}, {1}".format(sh.server_version,
name)
return ret
ret += " FAILURE "
errors = []
for msg in result:
if isinstance(msg, ClientHello):
continue
# check if returned message supports custom formatting
if msg.__class__.__format__ is not object.__format__:
errors += ["{:vxm}".format(msg)]
else:
errors += [repr(msg)]
# skip printing close errors after fatal alerts, they are expected
if isinstance(msg, Alert) and msg.level == AlertLevel.fatal:
break
ret += "\n".join(errors)
return ret
configs = {}
def load_configs():
"""Load known client configurations for later use in scanning."""
base_configs = [Xmas_tree, Firefox_42, IE_8_Win_XP, IE_11_Win_7,
VeryCompatible]
for conf in base_configs:
# only no extensions
gen = no_extensions(conf())
configs[gen.name] = gen
gen = no_sni(conf())
configs[gen.name] = gen
for version in ((3, 1), (3, 2), (3, 3), (3, 4), (3, 5), (3, 254)):
if conf().version != version:
# just changed version
gen = set_hello_version(conf(), version)
if gen.record_version > version:
gen = set_record_version(gen, version)
configs[gen.name] = gen
# changed version and no extensions
gen = set_hello_version(conf(), version)
if gen.record_version > version:
gen = set_record_version(gen, version)
gen = no_extensions(gen)
configs[gen.name] = gen
# changed version and no sni
gen = set_hello_version(conf(), version)
if gen.record_version > version:
gen = set_record_version(gen, version)
gen = no_sni(gen)
configs[gen.name] = gen
# Xmas tree configs
gen = Xmas_tree()
configs[gen.name] = gen
gen = no_sni(Xmas_tree())
configs[gen.name] = gen
# Firefox 42 configs
gen = Firefox_42()
configs[gen.name] = gen
# Firefox 46 configs
gen = Firefox_46()
configs[gen.name] = gen
gen = set_hello_version(Firefox_46(), (3, 254))
configs[gen.name] = gen
gen = set_hello_version(Firefox_46(), (3, 5))
configs[gen.name] = gen
gen = no_extensions(set_hello_version(Firefox_46(), (3, 5)))
configs[gen.name] = gen
gen = set_hello_version(Firefox_46(), (3, 1))
configs[gen.name] = gen
# IE 6 configs
gen = IE_6()
configs[gen.name] = gen
gen = IE_6_ext_tls_1_0()
configs[gen.name] = gen
# IE 8 configs
gen = IE_8_Win_XP()
configs[gen.name] = gen
gen = extend_with_ext_to_size(IE_8_Win_XP(), 200)
configs[gen.name] = gen
for ext_id in (0, 1, 2, 3, 4, 5):
gen = add_empty_ext(IE_8_Win_XP(), ext_id)
configs[gen.name] = gen
# IE 11 on Win 7 configs
gen = IE_11_Win_7()
configs[gen.name] = gen
gen = no_sni(IE_11_Win_7())
configs[gen.name] = gen
gen = set_hello_version(no_sni(IE_11_Win_7()), (3, 2))
configs[gen.name] = gen
# IE 11 on Win 8.1 configs
gen = IE_11_Win_8_1()
configs[gen.name] = gen
gen = set_hello_version(IE_11_Win_8_1(), (3, 1))
configs[gen.name] = gen
gen = set_hello_version(IE_11_Win_8_1(), (3, 4))
configs[gen.name] = gen
# Huge Cipher List
gen = HugeCipherList()
configs[gen.name] = gen
gen = truncate_ciphers_to_size(HugeCipherList(), 16388)
configs[gen.name] = gen
# Very Compatible
gen = VeryCompatible()
configs[gen.name] = gen
gen = append_ciphers_to_size(VeryCompatible(), 2**16)
configs[gen.name] = gen
gen = extend_with_ext_to_size(VeryCompatible(), 2**16)
configs[gen.name] = gen
gen = extend_with_ext_to_size(VeryCompatible(), 16388)
configs[gen.name] = gen
def scan_TLS_intolerancies(host, port, hostname):
"""Look for intolerancies (version, extensions, ...) in a TLS server."""
results = {}
def result_iterator(predicate):
"""
Selecting iterator over cached results.
Looks for matching result from already performed scans
"""
return (not simple_inspector(results[name]) for name in results
if predicate(configs[name]))
def result_cache(name, conf):
"""Perform scan if config is not in results, caches result."""
return results[name] if name in results \
else results.setdefault(name, scan_with_config(host, port, conf,
hostname))
def conf_iterator(predicate):
"""
Caching, selecting iterator over configs.
Returns an iterator that will go over configs that match the provided
predicate (a function that returns true or false depending if given
config is ok for test at hand) while saving the results to the
cache/verbose `results` log/dictionary
"""
scan_iter = (not simple_inspector(result_cache(name, conf))
for name, conf in configs.items()
if predicate(conf))
return itertools.chain(result_iterator(predicate), scan_iter)
host_up = not all(conf_iterator(lambda conf: True))
intolerancies = {}
if not host_up:
if json_out:
print(json.dumps(intolerancies))
else:
print("Host does not seem to support SSL or TLS protocol")
return
intolerancies["SSL 3.254"] = all(conf_iterator(lambda conf:
conf.version == (3, 254)))
intolerancies["TLS 1.4"] = all(conf_iterator(lambda conf:
conf.version == (3, 5)))
intolerancies["TLS 1.3"] = all(conf_iterator(lambda conf:
conf.version == (3, 4)))
intolerancies["TLS 1.2"] = all(conf_iterator(lambda conf:
conf.version == (3, 3)))
intolerancies["TLS 1.1"] = all(conf_iterator(lambda conf:
conf.version == (3, 2)))
intolerancies["TLS 1.0"] = all(conf_iterator(lambda conf:
conf.version == (3, 1)))
intolerancies["extensions"] = all(conf_iterator(lambda conf:
conf.extensions and not
conf.ssl2))
if json_out:
print(json.dumps(intolerancies))
else:
if not no_header:
if verbose:
print()
print("Host {0}:{1} scan complete".format(host, port))
if hostname:
print("SNI hostname used: {0}".format(hostname))
if verbose:
print()
print("Individual probe results:")
for desc, ret in sorted(results.items()):
print(verbose_inspector(desc, ret))
print()
print("Intolerance to:")
for intolerance, value in sorted(intolerancies.items()):
print(" {0:20}: {1}".format(intolerance,
"PRESENT" if value else "absent"))
def single_probe(name):
"""Run a single probe against a server, print result."""
print(verbose_inspector(name, scan_with_config(host, port,
configs[name], hostname)))
def usage():
"""Print usage information."""
print("./cscan.py [ARGUMENTS] host[:port] [SNI-HOST-NAME]")
print()
print("-l, --list List probe names")
print("-p name, --probe Run just a single probe")
print("-j, --json Output in JSON format")
print("-v, --verbose Use verbose output")
if __name__ == "__main__":
try:
opts, args = getopt.getopt(sys.argv[1:],
"jvhlp:",
["json", "verbose", "help", "list",
"probe=", "no-header"])
except getopt.GetoptError as err:
print(err)
usage()
sys.exit(2)
json_out = False
verbose = False
list_probes = False
run_probe = None
no_header = False
for opt, arg in opts:
if opt in ('-j', '--json'):
json_out = True
elif opt in ('-v', '--verbose'):
verbose = True
elif opt in ('-h', '--help'):
usage()
sys.exit(0)
elif opt in ('-l', '--list'):
list_probes = True
elif opt in ('-p', '--probe'):
run_probe = arg
elif opt in ('--no-header', ):
no_header = True
else:
raise AssertionError("Unknown option {0}".format(opt))
if len(args) > 2:
print("Too many arguments")
usage()
sys.exit(2)
load_configs()
if list_probes:
for desc, ret in sorted(configs.items()):
print("{0}: {1}".format(desc, ret.__doc__))
sys.exit(0)
hostname = None
if len(args) == 2:
hostname = args[1]
hostaddr = args[0].split(":")
if len(hostaddr) > 1:
host, port = hostaddr
else:
host = hostaddr[0]
port = 443
if run_probe:
single_probe(run_probe)
else:
scan_TLS_intolerancies(host, port, hostname)