# Author: Hubert Kario, (c) 2016
# Released under Gnu GPL v2.0, see LICENSE file for details
"""Tests for SNI resumption"""
from __future__ import print_function
import traceback
import sys
import getopt
import re
from itertools import chain
from random import sample

from tlsfuzzer.runner import Runner
from tlsfuzzer.messages import Connect, ClientHelloGenerator, \
        ClientKeyExchangeGenerator, ChangeCipherSpecGenerator, \
        FinishedGenerator, ApplicationDataGenerator, AlertGenerator, Close, \
        ResetHandshakeHashes, ResetRenegotiationInfo
from tlsfuzzer.expect import ExpectServerHello, ExpectCertificate, \
        ExpectServerHelloDone, ExpectChangeCipherSpec, ExpectFinished, \
        ExpectAlert, ExpectClose, ExpectApplicationData, \
        ExpectServerKeyExchange

from tlslite.constants import CipherSuite, AlertLevel, AlertDescription, \
        ExtensionType, HashAlgorithm, SignatureAlgorithm, GroupName
from tlslite.extensions import TLSExtension, SignatureAlgorithmsExtension, \
        SNIExtension, SignatureAlgorithmsCertExtension, \
        SupportedGroupsExtension
from tlsfuzzer.utils.lists import natural_sort_keys
from tlsfuzzer.helpers import RSA_SIG_ALL, AutoEmptyExtension


version = 5


def help_msg():
    print("Usage: <script-name> [-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(all)")
    print("                (excluding \"sanity\" tests)")
    print(" --sni hostname name of host used in SNI extension, \"localhost4\"")
    print("                by default")
    print(" -d             negotiate (EC)DHE instead of RSA key exchange, send")
    print("                additional extensions, usually used for (EC)DHE ciphers")
    print(" -M | --ems     Enable support for Extended Master Secret")
    print(" --help         this message")

def main():
    """check if server handles incorrect resumption w/server name indication"""
    host = "localhost"
    hostname = "localhost4"
    port = 4433
    num_limit = None
    run_exclude = set()
    expected_failures = {}
    last_exp_tmp = None
    dhe = False
    ems = False

    argv = sys.argv[1:]
    opts, args = getopt.getopt(argv, "h:p:e:x:X:n:dM", ["help", "sni=", "ems"])
    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 == '-d':
            dhe = True
        elif opt == '-M' or opt == '--ems':
            ems = True
        elif opt == '--help':
            help_msg()
            sys.exit(0)
        elif opt == '--sni':
            hostname = arg
        else:
            raise ValueError("Unknown option: {0}".format(opt))

    if args:
        run_only = set(args)
    else:
        run_only = None

    conversations = {}

    # sanity check without SNI
    conversation = Connect(host, port)
    node = conversation
    ext = {ExtensionType.signature_algorithms :
           SignatureAlgorithmsExtension().create([
             (getattr(HashAlgorithm, x),
              SignatureAlgorithm.rsa) for x in ['sha512', 'sha384', 'sha256',
                                                'sha224', 'sha1']]),
           ExtensionType.signature_algorithms_cert :
           SignatureAlgorithmsCertExtension().create(RSA_SIG_ALL)}
    if ems:
        ext[ExtensionType.extended_master_secret] = AutoEmptyExtension()
    if dhe:
        ciphers = [CipherSuite.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
                   CipherSuite.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
                   CipherSuite.TLS_DHE_RSA_WITH_AES_128_CBC_SHA,
                   CipherSuite.TLS_EMPTY_RENEGOTIATION_INFO_SCSV]
        groups = [GroupName.secp256r1,
                  GroupName.ffdhe2048]
        ext[ExtensionType.supported_groups] = SupportedGroupsExtension()\
            .create(groups)
    else:
        ciphers = [CipherSuite.TLS_RSA_WITH_AES_128_CBC_SHA,
                   CipherSuite.TLS_EMPTY_RENEGOTIATION_INFO_SCSV]
    node = node.add_child(ClientHelloGenerator(ciphers, extensions=ext))
    node = node.add_child(ExpectServerHello(version=(3, 3)))
    node = node.add_child(ExpectCertificate())
    if dhe:
        node = node.add_child(ExpectServerKeyExchange())
    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(b"GET / HTTP/1.0\n\n"))
    node = node.add_child(ExpectApplicationData())
    node = node.add_child(AlertGenerator(AlertDescription.close_notify))
    node = node.add_child(ExpectClose())
    node.next_sibling = ExpectAlert(AlertLevel.warning,
                                    AlertDescription.close_notify)
    node.next_sibling.add_child(ExpectClose())
    conversations["sanity"] = conversation

    # sanity check SNI
    conversation = Connect(host, port)
    node = conversation
    ext = {ExtensionType.signature_algorithms :
           SignatureAlgorithmsExtension().create([
             (getattr(HashAlgorithm, x),
              SignatureAlgorithm.rsa) for x in ['sha512', 'sha384', 'sha256',
                                                'sha224', 'sha1']]),
           ExtensionType.signature_algorithms_cert :
           SignatureAlgorithmsCertExtension().create(RSA_SIG_ALL)}
    if ems:
        ext[ExtensionType.extended_master_secret] = AutoEmptyExtension()
    if dhe:
        ciphers = [CipherSuite.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
                   CipherSuite.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
                   CipherSuite.TLS_DHE_RSA_WITH_AES_128_CBC_SHA,
                   CipherSuite.TLS_EMPTY_RENEGOTIATION_INFO_SCSV]
        groups = [GroupName.secp256r1,
                  GroupName.ffdhe2048]
        ext[ExtensionType.supported_groups] = SupportedGroupsExtension()\
            .create(groups)
    else:
        ciphers = [CipherSuite.TLS_RSA_WITH_AES_128_CBC_SHA,
                   CipherSuite.TLS_EMPTY_RENEGOTIATION_INFO_SCSV]
    sni = SNIExtension().create(bytearray(hostname, 'utf-8'))
    ext[ExtensionType.server_name] = sni
    node = node.add_child(ClientHelloGenerator(ciphers, extensions=ext))
    node = node.add_child(ExpectServerHello(version=(3, 3)))
    node = node.add_child(ExpectCertificate())
    if dhe:
        node = node.add_child(ExpectServerKeyExchange())
    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(b"GET / HTTP/1.0\n\n"))
    node = node.add_child(ExpectApplicationData())
    node = node.add_child(AlertGenerator(AlertDescription.close_notify))
    node = node.add_child(ExpectClose())
    node.next_sibling = ExpectAlert(AlertLevel.warning,
                                    AlertDescription.close_notify)
    node.next_sibling.add_child(ExpectClose())
    conversations["Sanity check, SNI"] = conversation

    # sanity check bad SNI
    conversation = Connect(host, port)
    node = conversation
    ext = {ExtensionType.signature_algorithms :
           SignatureAlgorithmsExtension().create([
             (getattr(HashAlgorithm, x),
              SignatureAlgorithm.rsa) for x in ['sha512', 'sha384', 'sha256',
                                                'sha224', 'sha1']]),
           ExtensionType.signature_algorithms_cert :
           SignatureAlgorithmsCertExtension().create(RSA_SIG_ALL)}
    if ems:
        ext[ExtensionType.extended_master_secret] = AutoEmptyExtension()
    if dhe:
        ciphers = [CipherSuite.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
                   CipherSuite.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
                   CipherSuite.TLS_DHE_RSA_WITH_AES_128_CBC_SHA,
                   CipherSuite.TLS_EMPTY_RENEGOTIATION_INFO_SCSV]
        groups = [GroupName.secp256r1,
                  GroupName.ffdhe2048]
        ext[ExtensionType.supported_groups] = SupportedGroupsExtension()\
            .create(groups)
    else:
        ciphers = [CipherSuite.TLS_RSA_WITH_AES_128_CBC_SHA,
                   CipherSuite.TLS_EMPTY_RENEGOTIATION_INFO_SCSV]
    sni = SNIExtension().create(bytearray(hostname, 'utf-8') +
                                bytearray(b'\x00'))
    ext[ExtensionType.server_name] = sni
    node = node.add_child(ClientHelloGenerator(ciphers, extensions=ext))
    node = node.add_child(ExpectAlert(AlertLevel.fatal,
                                      AlertDescription.illegal_parameter))
    node = node.add_child(ExpectClose())
    conversations["Sanity check, bad SNI"] = conversation

    # session resume with malformed SNI
    conversation = Connect(host, port)
    node = conversation
    ext = {ExtensionType.renegotiation_info : None,
           ExtensionType.server_name : SNIExtension().create(
                                       bytearray(hostname, 'utf-8'))
          }
    if ems:
        ext[ExtensionType.extended_master_secret] = AutoEmptyExtension()
    if dhe:
        ciphers = [CipherSuite.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
                   CipherSuite.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
                   CipherSuite.TLS_DHE_RSA_WITH_AES_128_CBC_SHA]
        groups = [GroupName.secp256r1,
                  GroupName.ffdhe2048]
        ext[ExtensionType.supported_groups] = SupportedGroupsExtension()\
            .create(groups)
    else:
        ciphers = [CipherSuite.TLS_RSA_WITH_AES_128_CBC_SHA]
    node = node.add_child(ClientHelloGenerator(
        ciphers,
        session_id=bytearray(32),
        extensions=ext))
    node = node.add_child(ExpectServerHello())
    node = node.add_child(ExpectCertificate())
    if dhe:
        node = node.add_child(ExpectServerKeyExchange())
    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(AlertGenerator(AlertLevel.warning,
                                         AlertDescription.close_notify))
    node = node.add_child(ExpectAlert(AlertLevel.warning,
                                      AlertDescription.close_notify))
    close = ExpectClose()
    node.next_sibling = close
    node = node.add_child(ExpectClose())
    node = node.add_child(Close())
    node = node.add_child(Connect(host, port))
    close.add_child(node)

    node = node.add_child(ResetHandshakeHashes())
    node = node.add_child(ResetRenegotiationInfo())
    ext = {ExtensionType.renegotiation_info:None,
           ExtensionType.server_name:SNIExtension().create(bytearray(hostname, 'utf-8') +
                                                           bytearray(b'\x00'))}
    node = node.add_child(ClientHelloGenerator(
        ciphers,
        extensions=ext))
    node = node.add_child(ExpectAlert(AlertLevel.fatal,
                                      AlertDescription.illegal_parameter))
    node.next_sibling = ExpectClose()
    node = node.add_child(ExpectClose())

    conversations["session resume with malformed SNI"] = conversation

    # session resume with malformed SNI
    conversation = Connect(host, port)
    node = conversation
    ext = {ExtensionType.renegotiation_info : None,
           ExtensionType.server_name : SNIExtension().create(
                                       bytearray(hostname, 'utf-8'))
          }
    if ems:
        ext[ExtensionType.extended_master_secret] = AutoEmptyExtension()
    if dhe:
        ciphers = [CipherSuite.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
                   CipherSuite.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
                   CipherSuite.TLS_DHE_RSA_WITH_AES_128_CBC_SHA]
        groups = [GroupName.secp256r1,
                  GroupName.ffdhe2048]
        ext[ExtensionType.supported_groups] = SupportedGroupsExtension()\
            .create(groups)
    else:
        ciphers = [CipherSuite.TLS_RSA_WITH_AES_128_CBC_SHA]
    node = node.add_child(ClientHelloGenerator(
        ciphers,
        session_id=bytearray(32),
        extensions=ext))
    node = node.add_child(ExpectServerHello())
    node = node.add_child(ExpectCertificate())
    if dhe:
        node = node.add_child(ExpectServerKeyExchange())
    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(AlertGenerator(AlertLevel.warning,
                                         AlertDescription.close_notify))
    node = node.add_child(ExpectAlert(AlertLevel.warning,
                                      AlertDescription.close_notify))
    close = ExpectClose()
    node.next_sibling = close
    node = node.add_child(ExpectClose())
    node = node.add_child(Close())
    node = node.add_child(Connect(host, port))
    close.add_child(node)

    node = node.add_child(ResetHandshakeHashes())
    node = node.add_child(ResetRenegotiationInfo())
    ext = {ExtensionType.renegotiation_info:None,
           ExtensionType.server_name:SNIExtension().create(bytearray(b'www.') +
                                                           bytearray(hostname, 'utf-8'))}
    if ems:
        ext[ExtensionType.extended_master_secret] = AutoEmptyExtension()
    node = node.add_child(ClientHelloGenerator(
        ciphers,
        extensions=ext))
    srv_ext = {ExtensionType.renegotiation_info: None}
    if ems:
        srv_ext[ExtensionType.extended_master_secret] = None
    node = node.add_child(ExpectServerHello(
        extensions=srv_ext,
        resume=False))
    node = node.add_child(ExpectCertificate())
    if dhe:
        node = node.add_child(ExpectServerKeyExchange())
    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(AlertLevel.warning,
                                      AlertDescription.close_notify))
    node.next_sibling = ExpectClose()
    node = node.add_child(ExpectClose())

    conversations["session resume with different SNI"] = 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
        print("{0} ...".format(c_name))

        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")
        else:
            if res:
                good += 1
                print("OK\n")
            else:
                bad += 1
                failed.append(c_name)

    print("\nSNI resumption test")

    print("In case the \"session resume with malformed SNI\" or the")
    print("\"session resume with different SNI\" test case")
    print("the server replies with ChangeCipherSpec when we expect")
    print("ExpectCertificate, it means it does not follow a \"MUST NOT\"")
    print("clause of RFC 6066 Section 3\n")

    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()
