# Author: Hubert Kario, (c) 2018 # Released under Gnu GPL v2.0, see LICENSE file for details """Test for correct handling of zero-padded ECDHE shared secrets.""" from __future__ import print_function import traceback import sys import getopt from itertools import chain from random import sample from tlsfuzzer.runner import Runner from tlsfuzzer.messages import Connect, ClientHelloGenerator, \ ClientKeyExchangeGenerator, ChangeCipherSpecGenerator, \ FinishedGenerator, ApplicationDataGenerator, AlertGenerator, \ CopyVariables from tlsfuzzer.expect import ExpectServerHello, ExpectCertificate, \ ExpectServerHelloDone, ExpectChangeCipherSpec, ExpectFinished, \ ExpectAlert, ExpectClose, ExpectServerKeyExchange, \ ExpectApplicationData from tlsfuzzer.utils.lists import natural_sort_keys from tlslite.constants import CipherSuite, AlertLevel, AlertDescription, \ ExtensionType, GroupName, ECPointFormat from tlslite.extensions import ECPointFormatsExtension, \ SupportedGroupsExtension version = 5 def help_msg(): print("Usage: [-h hostname] [-p port] [[probe-name] ...]") print(" -h hostname name of the host to run the test against") print(" localhost by default") print(" -p port port number to use for connection, 4433 by default") print(" probe-name if present, will run only the probes with given") print(" names and not all of them, e.g \"sanity\"") print(" -e probe-name exclude the probe from the list of the ones run") print(" may be specified multiple times") print(" -x probe-name expect the probe to fail. When such probe passes despite being marked like this") print(" it will be reported in the test summary and the whole script will fail.") print(" May be specified multiple times.") print(" -X message expect the `message` substring in exception raised during") print(" execution of preceding expected failure probe") print(" usage: [-x probe-name] [-X exception], order is compulsory!") print(" -n num run 'num' or all(if 0) tests instead of default(1)") print(" (excluding \"sanity\" tests)") print(" --min-zeros m minimal number of zeros that have to be cut from") print(" shared secret for test case to be valid,") print(" 1 by default") print(" -z don't expect 1/n-1 record split in TLS1.0") print(" --help this message") def main(): """Verify correct ECDHE shared secret handling.""" host = "localhost" port = 4433 num_limit = 1 run_exclude = set() expected_failures = {} last_exp_tmp = None min_zeros = 1 record_split = True argv = sys.argv[1:] opts, args = getopt.getopt(argv, "h:p:e:x:X:n:z", ["help", "min-zeros="]) for opt, arg in opts: if opt == '-h': host = arg elif opt == '-p': port = int(arg) elif opt == '-e': run_exclude.add(arg) elif opt == '-x': expected_failures[arg] = None last_exp_tmp = str(arg) elif opt == '-X': if not last_exp_tmp: raise ValueError("-x has to be specified before -X") expected_failures[last_exp_tmp] = str(arg) elif opt == '-n': num_limit = int(arg) elif opt == '-z': record_split = False elif opt == '--help': help_msg() sys.exit(0) elif opt == '--min-zeros': min_zeros = int(arg) else: raise ValueError("Unknown option: {0}".format(opt)) if args: run_only = set(args) else: run_only = None collected_premaster_secrets = [] variables_check = \ {'premaster_secret': collected_premaster_secrets} groups = [GroupName.x25519, GroupName.x448, GroupName.secp256r1, GroupName.secp384r1, GroupName.secp521r1] conversations = {} conversation = Connect(host, port) node = conversation ciphers = [CipherSuite.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA] groups_ext = SupportedGroupsExtension().create(groups) points_ext = ECPointFormatsExtension().create([ECPointFormat.uncompressed]) exts = {ExtensionType.renegotiation_info: None, ExtensionType.supported_groups: groups_ext, ExtensionType.ec_point_formats: points_ext} node = node.add_child(ClientHelloGenerator(ciphers, extensions=exts)) exts = {ExtensionType.renegotiation_info:None, ExtensionType.ec_point_formats: None} node = node.add_child(ExpectServerHello(extensions=exts)) node = node.add_child(ExpectCertificate()) node = node.add_child(ExpectServerKeyExchange()) node = node.add_child(CopyVariables(variables_check)) node = node.add_child(ExpectServerHelloDone()) node = node.add_child(ClientKeyExchangeGenerator()) node = node.add_child(ChangeCipherSpecGenerator()) node = node.add_child(FinishedGenerator()) node = node.add_child(ExpectChangeCipherSpec()) node = node.add_child(ExpectFinished()) node = node.add_child(ApplicationDataGenerator( bytearray(b"GET / HTTP/1.0\n\n"))) node = node.add_child(ExpectApplicationData()) node = node.add_child(AlertGenerator(AlertLevel.warning, AlertDescription.close_notify)) node = node.add_child(ExpectAlert()) node.next_sibling = ExpectClose() conversations["sanity"] = conversation for prot in [(3, 0), (3, 1), (3, 2), (3, 3)]: for ssl2 in [True, False]: for group in groups: # with SSLv2 compatible or with SSLv3 we can't advertise # curves so do just one check if (ssl2 or prot == (3, 0)) and group != groups[0]: continue conversation = Connect(host, port, version=(0, 2) if ssl2 else (3, 0)) node = conversation ciphers = [CipherSuite.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA, CipherSuite.TLS_EMPTY_RENEGOTIATION_INFO_SCSV] if ssl2 or prot == (3, 0): exts = None else: groups_ext = SupportedGroupsExtension().create([group]) exts = {ExtensionType.supported_groups: groups_ext, ExtensionType.ec_point_formats: points_ext} node = node.add_child(ClientHelloGenerator(ciphers, version=prot, extensions=exts, ssl2=ssl2)) if prot > (3, 0): if ssl2: ext = {ExtensionType.renegotiation_info: None} else: ext = {ExtensionType.renegotiation_info: None, ExtensionType.ec_point_formats: None} else: ext = None node = node.add_child(ExpectServerHello(extensions=ext, version=prot)) node = node.add_child(ExpectCertificate()) node = node.add_child(ExpectServerKeyExchange()) node = node.add_child(CopyVariables(variables_check)) node = node.add_child(ExpectServerHelloDone()) node = node.add_child(ClientKeyExchangeGenerator()) node = node.add_child(ChangeCipherSpecGenerator()) node = node.add_child(FinishedGenerator()) node = node.add_child(ExpectChangeCipherSpec()) node = node.add_child(ExpectFinished()) node = node.add_child(ApplicationDataGenerator( bytearray(b"GET / HTTP/1.0\n\n"))) node = node.add_child(ExpectApplicationData()) if prot < (3, 2) and record_split: # 1/n-1 record splitting node = node.add_child(ExpectApplicationData()) node = node.add_child(AlertGenerator(AlertLevel.warning, AlertDescription.close_notify)) node = node.add_child(ExpectAlert()) node.next_sibling = ExpectClose() conversations["Protocol {0}{1}{2}".format( prot, "" if ssl2 or prot < (3, 1) else " with {0} group".format(GroupName.toStr(group)), " in SSLv2 compatible ClientHello" if ssl2 else "")] = \ conversation # run the conversation good = 0 bad = 0 xfail = 0 xpass = 0 failed = [] xpassed = [] if not num_limit: num_limit = len(conversations) # make sure that sanity test is run first and last # to verify that server was running and kept running throughout sanity_tests = [('sanity', conversations['sanity'])] if run_only: if num_limit > len(run_only): num_limit = len(run_only) regular_tests = [(k, v) for k, v in conversations.items() if k in run_only] else: regular_tests = [(k, v) for k, v in conversations.items() if (k != 'sanity') and k not in run_exclude] sampled_tests = sample(regular_tests, min(num_limit, len(regular_tests))) ordered_tests = chain(sanity_tests, sampled_tests, sanity_tests) for c_name, c_test in ordered_tests: if run_only and c_name not in run_only or c_name in run_exclude: continue i = 0 break_loop = False while True: # don't hog the memory unnecessairly collected_premaster_secrets[:] = [] print("\"{1}\" repeat {0}...".format(i, c_name)) i += 1 if c_name == 'sanity': break_loop = True runner = Runner(c_test) res = True exception = None try: runner.run() except Exception as exp: exception = exp print("Error while processing") print(traceback.format_exc()) res = False if c_name in expected_failures: if res: xpass += 1 xpassed.append(c_name) print("XPASS-expected failure but test passed\n") else: if expected_failures[c_name] is not None and \ expected_failures[c_name] not in str(exception): bad += 1 failed.append(c_name) print("Expected error message: {0}\n" .format(expected_failures[c_name])) else: xfail += 1 print("OK-expected failure\n") break_loop = True else: if res: good += 1 if collected_premaster_secrets[-1][:min_zeros] == \ bytearray(min_zeros): print("Got premaster secret with {0} most significant " "bytes equal to zero." .format(min_zeros)) break_loop = True print("OK\n") else: bad += 1 failed.append(c_name) break_loop = True if break_loop: break print('') print("Check if the connections work when the calculated ECDH shared") print("secret must be padded on the left with zeros") print("Test end") print(20 * '=') print("version: {0}".format(version)) print(20 * '=') print("TOTAL: {0}".format(len(sampled_tests) + 2*len(sanity_tests))) print("SKIP: {0}".format(len(run_exclude.intersection(conversations.keys())))) print("PASS: {0}".format(good)) print("XFAIL: {0}".format(xfail)) print("FAIL: {0}".format(bad)) print("XPASS: {0}".format(xpass)) print(20 * '=') sort = sorted(xpassed ,key=natural_sort_keys) if len(sort): print("XPASSED:\n\t{0}".format('\n\t'.join(repr(i) for i in sort))) sort = sorted(failed, key=natural_sort_keys) if len(sort): print("FAILED:\n\t{0}".format('\n\t'.join(repr(i) for i in sort))) if bad or xpass: sys.exit(1) if __name__ == "__main__": main()