text: # Test the support for SSL and sockets
  
  import sys
  import unittest
  import unittest.mock
  from test import support
  import socket
  import select
  import time
  import datetime
  import gc
  import os
  import errno
  import pprint
  import urllib.request
  import threading
  import traceback
  import asyncore
  import weakref
  import platform
  import sysconfig
  try:
      import ctypes
  except ImportError:
      ctypes = None
  
  ssl = support.import_module("ssl")
  
  from ssl import TLSVersion, _TLSContentType, _TLSMessageType
  
  Py_DEBUG = hasattr(sys, 'gettotalrefcount')
  Py_DEBUG_WIN32 = Py_DEBUG and sys.platform == 'win32'
  
  PROTOCOLS = sorted(ssl._PROTOCOL_NAMES)
  HOST = support.HOST
  IS_LIBRESSL = ssl.OPENSSL_VERSION.startswith('LibreSSL')
  IS_OPENSSL_1_1_0 = not IS_LIBRESSL and ssl.OPENSSL_VERSION_INFO >= (1, 1, 0)
  IS_OPENSSL_1_1_1 = not IS_LIBRESSL and ssl.OPENSSL_VERSION_INFO >= (1, 1, 1)
  PY_SSL_DEFAULT_CIPHERS = sysconfig.get_config_var('PY_SSL_DEFAULT_CIPHERS')
  
  PROTOCOL_TO_TLS_VERSION = {}
  for proto, ver in (
      ("PROTOCOL_SSLv23", "SSLv3"),
      ("PROTOCOL_TLSv1", "TLSv1"),
      ("PROTOCOL_TLSv1_1", "TLSv1_1"),
  ):
      try:
          proto = getattr(ssl, proto)
          ver = getattr(ssl.TLSVersion, ver)
      except AttributeError:
          continue
      PROTOCOL_TO_TLS_VERSION[proto] = ver
  
  def data_file(*name):
      return os.path.join(os.path.dirname(__file__), *name)
  
  # The custom key and certificate files used in test_ssl are generated
  # using Lib/test/make_ssl_certs.py.
  # Other certificates are simply fetched from the Internet servers they
  # are meant to authenticate.
  
  CERTFILE = data_file("keycert.pem")
  BYTES_CERTFILE = os.fsencode(CERTFILE)
  ONLYCERT = data_file("ssl_cert.pem")
  ONLYKEY = data_file("ssl_key.pem")
  BYTES_ONLYCERT = os.fsencode(ONLYCERT)
  BYTES_ONLYKEY = os.fsencode(ONLYKEY)
  CERTFILE_PROTECTED = data_file("keycert.passwd.pem")
  ONLYKEY_PROTECTED = data_file("ssl_key.passwd.pem")
  KEY_PASSWORD = "somepass"
  CAPATH = data_file("capath")
  BYTES_CAPATH = os.fsencode(CAPATH)
  CAFILE_NEURONIO = data_file("capath", "4e1295a3.0")
  CAFILE_CACERT = data_file("capath", "5ed36f99.0")
  
  CERTFILE_INFO = {
      'issuer': ((('countryName', 'XY'),),
                 (('localityName', 'Castle Anthrax'),),
                 (('organizationName', 'Python Software Foundation'),),
                 (('commonName', 'localhost'),)),
      'notAfter': 'Aug 26 14:23:15 2028 GMT',
      'notBefore': 'Aug 29 14:23:15 2018 GMT',
      'serialNumber': '98A7CF88C74A32ED',
      'subject': ((('countryName', 'XY'),),
               (('localityName', 'Castle Anthrax'),),
               (('organizationName', 'Python Software Foundation'),),
               (('commonName', 'localhost'),)),
      'subjectAltName': (('DNS', 'localhost'),),
      'version': 3
  }
  
  # empty CRL
  CRLFILE = data_file("revocation.crl")
  
  # Two keys and certs signed by the same CA (for SNI tests)
  SIGNED_CERTFILE = data_file("keycert3.pem")
  SIGNED_CERTFILE_HOSTNAME = 'localhost'
  
  SIGNED_CERTFILE_INFO = {
      'OCSP': ('http://testca.pythontest.net/testca/ocsp/',),
      'caIssuers': ('http://testca.pythontest.net/testca/pycacert.cer',),
      'crlDistributionPoints': ('http://testca.pythontest.net/testca/revocation.crl',),
      'issuer': ((('countryName', 'XY'),),
              (('organizationName', 'Python Software Foundation CA'),),
              (('commonName', 'our-ca-server'),)),
      'notAfter': 'Jul  7 14:23:16 2028 GMT',
      'notBefore': 'Aug 29 14:23:16 2018 GMT',
      'serialNumber': 'CB2D80995A69525C',
      'subject': ((('countryName', 'XY'),),
               (('localityName', 'Castle Anthrax'),),
               (('organizationName', 'Python Software Foundation'),),
               (('commonName', 'localhost'),)),
      'subjectAltName': (('DNS', 'localhost'),),
      'version': 3
  }
  
  SIGNED_CERTFILE2 = data_file("keycert4.pem")
  SIGNED_CERTFILE2_HOSTNAME = 'fakehostname'
  SIGNED_CERTFILE_ECC = data_file("keycertecc.pem")
  SIGNED_CERTFILE_ECC_HOSTNAME = 'localhost-ecc'
  
  # Same certificate as pycacert.pem, but without extra text in file
  SIGNING_CA = data_file("capath", "ceff1710.0")
  # cert with all kinds of subject alt names
  ALLSANFILE = data_file("allsans.pem")
  IDNSANSFILE = data_file("idnsans.pem")
  
  REMOTE_HOST = "self-signed.pythontest.net"
  
  EMPTYCERT = data_file("nullcert.pem")
  BADCERT = data_file("badcert.pem")
  NONEXISTINGCERT = data_file("XXXnonexisting.pem")
  BADKEY = data_file("badkey.pem")
  NOKIACERT = data_file("nokia.pem")
  NULLBYTECERT = data_file("nullbytecert.pem")
  TALOS_INVALID_CRLDP = data_file("talos-2019-0758.pem")
  
  DHFILE = data_file("ffdh3072.pem")
  BYTES_DHFILE = os.fsencode(DHFILE)
  
  # Not defined in all versions of OpenSSL
  OP_NO_COMPRESSION = getattr(ssl, "OP_NO_COMPRESSION", 0)
  OP_SINGLE_DH_USE = getattr(ssl, "OP_SINGLE_DH_USE", 0)
  OP_SINGLE_ECDH_USE = getattr(ssl, "OP_SINGLE_ECDH_USE", 0)
  OP_CIPHER_SERVER_PREFERENCE = getattr(ssl, "OP_CIPHER_SERVER_PREFERENCE", 0)
  OP_ENABLE_MIDDLEBOX_COMPAT = getattr(ssl, "OP_ENABLE_MIDDLEBOX_COMPAT", 0)
  
  
  def handle_error(prefix):
      exc_format = ' '.join(traceback.format_exception(*sys.exc_info()))
      if support.verbose:
          sys.stdout.write(prefix + exc_format)
  
  def can_clear_options():
      # 0.9.8m or higher
      return ssl._OPENSSL_API_VERSION >= (0, 9, 8, 13, 15)
  
  def no_sslv2_implies_sslv3_hello():
      # 0.9.7h or higher
      return ssl.OPENSSL_VERSION_INFO >= (0, 9, 7, 8, 15)
  
  def have_verify_flags():
      # 0.9.8 or higher
      return ssl.OPENSSL_VERSION_INFO >= (0, 9, 8, 0, 15)
  
  def _have_secp_curves():
      if not ssl.HAS_ECDH:
          return False
      ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
      try:
          ctx.set_ecdh_curve("secp384r1")
      except ValueError:
          return False
      else:
          return True
  
  
  HAVE_SECP_CURVES = _have_secp_curves()
  
  
  def utc_offset(): #NOTE: ignore issues like #1647654
      # local time = utc time + utc offset
      if time.daylight and time.localtime().tm_isdst > 0:
          return -time.altzone  # seconds
      return -time.timezone
  
  def asn1time(cert_time):
      # Some versions of OpenSSL ignore seconds, see #18207
      # 0.9.8.i
      if ssl._OPENSSL_API_VERSION == (0, 9, 8, 9, 15):
          fmt = "%b %d %H:%M:%S %Y GMT"
          dt = datetime.datetime.strptime(cert_time, fmt)
          dt = dt.replace(second=0)
          cert_time = dt.strftime(fmt)
          # %d adds leading zero but ASN1_TIME_print() uses leading space
          if cert_time[4] == "0":
              cert_time = cert_time[:4] + " " + cert_time[5:]
  
      return cert_time
  
  needs_sni = unittest.skipUnless(ssl.HAS_SNI, "SNI support needed for this test")
  
  
  def test_wrap_socket(sock, ssl_version=ssl.PROTOCOL_TLS, *,
                       cert_reqs=ssl.CERT_NONE, ca_certs=None,
                       ciphers=None, certfile=None, keyfile=None,
                       **kwargs):
      context = ssl.SSLContext(ssl_version)
      if cert_reqs is not None:
          if cert_reqs == ssl.CERT_NONE:
              context.check_hostname = False
          context.verify_mode = cert_reqs
      if ca_certs is not None:
          context.load_verify_locations(ca_certs)
      if certfile is not None or keyfile is not None:
          context.load_cert_chain(certfile, keyfile)
      if ciphers is not None:
          context.set_ciphers(ciphers)
      return context.wrap_socket(sock, **kwargs)
  
  
  def testing_context(server_cert=SIGNED_CERTFILE):
      """Create context
  
      client_context, server_context, hostname = testing_context()
      """
      if server_cert == SIGNED_CERTFILE:
          hostname = SIGNED_CERTFILE_HOSTNAME
      elif server_cert == SIGNED_CERTFILE2:
          hostname = SIGNED_CERTFILE2_HOSTNAME
      else:
          raise ValueError(server_cert)
  
      client_context = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
      client_context.load_verify_locations(SIGNING_CA)
  
      server_context = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
      server_context.load_cert_chain(server_cert)
      server_context.load_verify_locations(SIGNING_CA)
  
      return client_context, server_context, hostname
  
  
  class BasicSocketTests(unittest.TestCase):
  
      def test_constants(self):
          ssl.CERT_NONE
          ssl.CERT_OPTIONAL
          ssl.CERT_REQUIRED
          ssl.OP_CIPHER_SERVER_PREFERENCE
          ssl.OP_SINGLE_DH_USE
          if ssl.HAS_ECDH:
              ssl.OP_SINGLE_ECDH_USE
          if ssl.OPENSSL_VERSION_INFO >= (1, 0):
              ssl.OP_NO_COMPRESSION
          self.assertIn(ssl.HAS_SNI, {True, False})
          self.assertIn(ssl.HAS_ECDH, {True, False})
          ssl.OP_NO_SSLv2
          ssl.OP_NO_SSLv3
          ssl.OP_NO_TLSv1
          ssl.OP_NO_TLSv1_3
          if ssl.OPENSSL_VERSION_INFO >= (1, 0, 1):
              ssl.OP_NO_TLSv1_1
              ssl.OP_NO_TLSv1_2
          self.assertEqual(ssl.PROTOCOL_TLS, ssl.PROTOCOL_SSLv23)
  
      def test_private_init(self):
          with self.assertRaisesRegex(TypeError, "public constructor"):
              with socket.socket() as s:
                  ssl.SSLSocket(s)
  
      def test_str_for_enums(self):
          # Make sure that the PROTOCOL_* constants have enum-like string
          # reprs.
          proto = ssl.PROTOCOL_TLS
          self.assertEqual(str(proto), '_SSLMethod.PROTOCOL_TLS')
          ctx = ssl.SSLContext(proto)
          self.assertIs(ctx.protocol, proto)
  
      def test_random(self):
          v = ssl.RAND_status()
          if support.verbose:
              sys.stdout.write("\n RAND_status is %d (%s)\n"
                               % (v, (v and "sufficient randomness") or
                                  "insufficient randomness"))
  
          data, is_cryptographic = ssl.RAND_pseudo_bytes(16)
          self.assertEqual(len(data), 16)
          self.assertEqual(is_cryptographic, v == 1)
          if v:
              data = ssl.RAND_bytes(16)
              self.assertEqual(len(data), 16)
          else:
              self.assertRaises(ssl.SSLError, ssl.RAND_bytes, 16)
  
          # negative num is invalid
          self.assertRaises(ValueError, ssl.RAND_bytes, -5)
          self.assertRaises(ValueError, ssl.RAND_pseudo_bytes, -5)
  
          if hasattr(ssl, 'RAND_egd'):
              self.assertRaises(TypeError, ssl.RAND_egd, 1)
              self.assertRaises(TypeError, ssl.RAND_egd, 'foo', 1)
          ssl.RAND_add("this is a random string", 75.0)
          ssl.RAND_add(b"this is a random bytes object", 75.0)
          ssl.RAND_add(bytearray(b"this is a random bytearray object"), 75.0)
  
      @unittest.skipUnless(os.name == 'posix', 'requires posix')
      def test_random_fork(self):
          status = ssl.RAND_status()
          if not status:
              self.fail("OpenSSL's PRNG has insufficient randomness")
  
          rfd, wfd = os.pipe()
          pid = os.fork()
          if pid == 0:
              try:
                  os.close(rfd)
                  child_random = ssl.RAND_pseudo_bytes(16)[0]
                  self.assertEqual(len(child_random), 16)
                  os.write(wfd, child_random)
                  os.close(wfd)
              except BaseException:
                  os._exit(1)
              else:
                  os._exit(0)
          else:
              os.close(wfd)
              self.addCleanup(os.close, rfd)
              _, status = os.waitpid(pid, 0)
              self.assertEqual(status, 0)
  
              child_random = os.read(rfd, 16)
              self.assertEqual(len(child_random), 16)
              parent_random = ssl.RAND_pseudo_bytes(16)[0]
              self.assertEqual(len(parent_random), 16)
  
              self.assertNotEqual(child_random, parent_random)
  
      maxDiff = None
  
      def test_parse_cert(self):
          # note that this uses an 'unofficial' function in _ssl.c,
          # provided solely for this test, to exercise the certificate
          # parsing code
          self.assertEqual(
              ssl._ssl._test_decode_cert(CERTFILE),
              CERTFILE_INFO
          )
          self.assertEqual(
              ssl._ssl._test_decode_cert(SIGNED_CERTFILE),
              SIGNED_CERTFILE_INFO
          )
  
          # Issue #13034: the subjectAltName in some certificates
          # (notably projects.developer.nokia.com:443) wasn't parsed
          p = ssl._ssl._test_decode_cert(NOKIACERT)
          if support.verbose:
              sys.stdout.write("\n" + pprint.pformat(p) + "\n")
          self.assertEqual(p['subjectAltName'],
                           (('DNS', 'projects.developer.nokia.com'),
                            ('DNS', 'projects.forum.nokia.com'))
                          )
          # extra OCSP and AIA fields
          self.assertEqual(p['OCSP'], ('http://ocsp.verisign.com',))
          self.assertEqual(p['caIssuers'],
                           ('http://SVRIntl-G3-aia.verisign.com/SVRIntlG3.cer',))
          self.assertEqual(p['crlDistributionPoints'],
                           ('http://SVRIntl-G3-crl.verisign.com/SVRIntlG3.crl',))
  
      def test_parse_cert_CVE_2019_5010(self):
          p = ssl._ssl._test_decode_cert(TALOS_INVALID_CRLDP)
          if support.verbose:
              sys.stdout.write("\n" + pprint.pformat(p) + "\n")
          self.assertEqual(
              p,
              {
                  'issuer': (
                      (('countryName', 'UK'),), (('commonName', 'cody-ca'),)),
                  'notAfter': 'Jun 14 18:00:58 2028 GMT',
                  'notBefore': 'Jun 18 18:00:58 2018 GMT',
                  'serialNumber': '02',
                  'subject': ((('countryName', 'UK'),),
                              (('commonName',
                                'codenomicon-vm-2.test.lal.cisco.com'),)),
                  'subjectAltName': (
                      ('DNS', 'codenomicon-vm-2.test.lal.cisco.com'),),
                  'version': 3
              }
          )
  
      def test_parse_cert_CVE_2013_4238(self):
          p = ssl._ssl._test_decode_cert(NULLBYTECERT)
          if support.verbose:
              sys.stdout.write("\n" + pprint.pformat(p) + "\n")
          subject = ((('countryName', 'US'),),
                     (('stateOrProvinceName', 'Oregon'),),
                     (('localityName', 'Beaverton'),),
                     (('organizationName', 'Python Software Foundation'),),
                     (('organizationalUnitName', 'Python Core Development'),),
                     (('commonName', 'null.python.org\x00example.org'),),
                     (('emailAddress', 'python-dev@python.org'),))
          self.assertEqual(p['subject'], subject)
          self.assertEqual(p['issuer'], subject)
          if ssl._OPENSSL_API_VERSION >= (0, 9, 8):
              san = (('DNS', 'altnull.python.org\x00example.com'),
                     ('email', 'null@python.org\x00user@example.org'),
                     ('URI', 'http://null.python.org\x00http://example.org'),
                     ('IP Address', '192.0.2.1'),
                     ('IP Address', '2001:DB8:0:0:0:0:0:1\n'))
          else:
              # OpenSSL 0.9.7 doesn't support IPv6 addresses in subjectAltName
              san = (('DNS', 'altnull.python.org\x00example.com'),
                     ('email', 'null@python.org\x00user@example.org'),
                     ('URI', 'http://null.python.org\x00http://example.org'),
                     ('IP Address', '192.0.2.1'),
                     ('IP Address', '<invalid>'))
  
          self.assertEqual(p['subjectAltName'], san)
  
      def test_parse_all_sans(self):
          p = ssl._ssl._test_decode_cert(ALLSANFILE)
          self.assertEqual(p['subjectAltName'],
              (
                  ('DNS', 'allsans'),
                  ('othername', '<unsupported>'),
                  ('othername', '<unsupported>'),
                  ('email', 'user@example.org'),
                  ('DNS', 'www.example.org'),
                  ('DirName',
                      ((('countryName', 'XY'),),
                      (('localityName', 'Castle Anthrax'),),
                      (('organizationName', 'Python Software Foundation'),),
                      (('commonName', 'dirname example'),))),
                  ('URI', 'https://www.python.org/'),
                  ('IP Address', '127.0.0.1'),
                  ('IP Address', '0:0:0:0:0:0:0:1\n'),
                  ('Registered ID', '1.2.3.4.5')
              )
          )
  
      def test_DER_to_PEM(self):
          with open(CAFILE_CACERT, 'r') as f:
              pem = f.read()
          d1 = ssl.PEM_cert_to_DER_cert(pem)
          p2 = ssl.DER_cert_to_PEM_cert(d1)
          d2 = ssl.PEM_cert_to_DER_cert(p2)
          self.assertEqual(d1, d2)
          if not p2.startswith(ssl.PEM_HEADER + '\n'):
              self.fail("DER-to-PEM didn't include correct header:\n%r\n" % p2)
          if not p2.endswith('\n' + ssl.PEM_FOOTER + '\n'):
              self.fail("DER-to-PEM didn't include correct footer:\n%r\n" % p2)
  
      def test_openssl_version(self):
          n = ssl.OPENSSL_VERSION_NUMBER
          t = ssl.OPENSSL_VERSION_INFO
          s = ssl.OPENSSL_VERSION
          self.assertIsInstance(n, int)
          self.assertIsInstance(t, tuple)
          self.assertIsInstance(s, str)
          # Some sanity checks follow
          # >= 0.9
          self.assertGreaterEqual(n, 0x900000)
          # < 3.0
          self.assertLess(n, 0x30000000)
          major, minor, fix, patch, status = t
          self.assertGreaterEqual(major, 0)
          self.assertLess(major, 3)
          self.assertGreaterEqual(minor, 0)
          self.assertLess(minor, 256)
          self.assertGreaterEqual(fix, 0)
          self.assertLess(fix, 256)
          self.assertGreaterEqual(patch, 0)
          self.assertLessEqual(patch, 63)
          self.assertGreaterEqual(status, 0)
          self.assertLessEqual(status, 15)
          # Version string as returned by {Open,Libre}SSL, the format might change
          if IS_LIBRESSL:
              self.assertTrue(s.startswith("LibreSSL {:d}".format(major)),
                              (s, t, hex(n)))
          else:
              self.assertTrue(s.startswith("OpenSSL {:d}.{:d}.{:d}".format(major, minor, fix)),
                              (s, t, hex(n)))
  
      @support.cpython_only
      def test_refcycle(self):
          # Issue #7943: an SSL object doesn't create reference cycles with
          # itself.
          s = socket.socket(socket.AF_INET)
          ss = test_wrap_socket(s)
          wr = weakref.ref(ss)
          with support.check_warnings(("", ResourceWarning)):
              del ss
          self.assertEqual(wr(), None)
  
      def test_wrapped_unconnected(self):
          # Methods on an unconnected SSLSocket propagate the original
          # OSError raise by the underlying socket object.
          s = socket.socket(socket.AF_INET)
          with test_wrap_socket(s) as ss:
              self.assertRaises(OSError, ss.recv, 1)
              self.assertRaises(OSError, ss.recv_into, bytearray(b'x'))
              self.assertRaises(OSError, ss.recvfrom, 1)
              self.assertRaises(OSError, ss.recvfrom_into, bytearray(b'x'), 1)
              self.assertRaises(OSError, ss.send, b'x')
              self.assertRaises(OSError, ss.sendto, b'x', ('0.0.0.0', 0))
              self.assertRaises(NotImplementedError, ss.dup)
              self.assertRaises(NotImplementedError, ss.sendmsg,
                                [b'x'], (), 0, ('0.0.0.0', 0))
              self.assertRaises(NotImplementedError, ss.recvmsg, 100)
              self.assertRaises(NotImplementedError, ss.recvmsg_into,
                                [bytearray(100)])
  
      def test_timeout(self):
          # Issue #8524: when creating an SSL socket, the timeout of the
          # original socket should be retained.
          for timeout in (None, 0.0, 5.0):
              s = socket.socket(socket.AF_INET)
              s.settimeout(timeout)
              with test_wrap_socket(s) as ss:
                  self.assertEqual(timeout, ss.gettimeout())
  
      def test_errors_sslwrap(self):
          sock = socket.socket()
          self.assertRaisesRegex(ValueError,
                          "certfile must be specified",
                          ssl.wrap_socket, sock, keyfile=CERTFILE)
          self.assertRaisesRegex(ValueError,
                          "certfile must be specified for server-side operations",
                          ssl.wrap_socket, sock, server_side=True)
          self.assertRaisesRegex(ValueError,
                          "certfile must be specified for server-side operations",
                           ssl.wrap_socket, sock, server_side=True, certfile="")
          with ssl.wrap_socket(sock, server_side=True, certfile=CERTFILE) as s:
              self.assertRaisesRegex(ValueError, "can't connect in server-side mode",
                                       s.connect, (HOST, 8080))
          with self.assertRaises(OSError) as cm:
              with socket.socket() as sock:
                  ssl.wrap_socket(sock, certfile=NONEXISTINGCERT)
          self.assertEqual(cm.exception.errno, errno.ENOENT)
          with self.assertRaises(OSError) as cm:
              with socket.socket() as sock:
                  ssl.wrap_socket(sock,
                      certfile=CERTFILE, keyfile=NONEXISTINGCERT)
          self.assertEqual(cm.exception.errno, errno.ENOENT)
          with self.assertRaises(OSError) as cm:
              with socket.socket() as sock:
                  ssl.wrap_socket(sock,
                      certfile=NONEXISTINGCERT, keyfile=NONEXISTINGCERT)
          self.assertEqual(cm.exception.errno, errno.ENOENT)
  
      def bad_cert_test(self, certfile):
          """Check that trying to use the given client certificate fails"""
          certfile = os.path.join(os.path.dirname(__file__) or os.curdir,
                                     certfile)
          sock = socket.socket()
          self.addCleanup(sock.close)
          with self.assertRaises(ssl.SSLError):
              test_wrap_socket(sock,
                               certfile=certfile)
  
      def test_empty_cert(self):
          """Wrapping with an empty cert file"""
          self.bad_cert_test("nullcert.pem")
  
      def test_malformed_cert(self):
          """Wrapping with a badly formatted certificate (syntax error)"""
          self.bad_cert_test("badcert.pem")
  
      def test_malformed_key(self):
          """Wrapping with a badly formatted key (syntax error)"""
          self.bad_cert_test("badkey.pem")
  
      def test_match_hostname(self):
          def ok(cert, hostname):
              ssl.match_hostname(cert, hostname)
          def fail(cert, hostname):
              self.assertRaises(ssl.CertificateError,
                                ssl.match_hostname, cert, hostname)
  
          # -- Hostname matching --
  
          cert = {'subject': ((('commonName', 'example.com'),),)}
          ok(cert, 'example.com')
          ok(cert, 'ExAmple.cOm')
          fail(cert, 'www.example.com')
          fail(cert, '.example.com')
          fail(cert, 'example.org')
          fail(cert, 'exampleXcom')
  
          cert = {'subject': ((('commonName', '*.a.com'),),)}
          ok(cert, 'foo.a.com')
          fail(cert, 'bar.foo.a.com')
          fail(cert, 'a.com')
          fail(cert, 'Xa.com')
          fail(cert, '.a.com')
  
          # only match wildcards when they are the only thing
          # in left-most segment
          cert = {'subject': ((('commonName', 'f*.com'),),)}
          fail(cert, 'foo.com')
          fail(cert, 'f.com')
          fail(cert, 'bar.com')
          fail(cert, 'foo.a.com')
          fail(cert, 'bar.foo.com')
  
          # NULL bytes are bad, CVE-2013-4073
          cert = {'subject': ((('commonName',
                                'null.python.org\x00example.org'),),)}
          ok(cert, 'null.python.org\x00example.org') # or raise an error?
          fail(cert, 'example.org')
          fail(cert, 'null.python.org')
  
          # error cases with wildcards
          cert = {'subject': ((('commonName', '*.*.a.com'),),)}
          fail(cert, 'bar.foo.a.com')
          fail(cert, 'a.com')
          fail(cert, 'Xa.com')
          fail(cert, '.a.com')
  
          cert = {'subject': ((('commonName', 'a.*.com'),),)}
          fail(cert, 'a.foo.com')
          fail(cert, 'a..com')
          fail(cert, 'a.com')
  
          # wildcard doesn't match IDNA prefix 'xn--'
          idna = 'püthon.python.org'.encode("idna").decode("ascii")
          cert = {'subject': ((('commonName', idna),),)}
          ok(cert, idna)
          cert = {'subject': ((('commonName', 'x*.python.org'),),)}
          fail(cert, idna)
          cert = {'subject': ((('commonName', 'xn--p*.python.org'),),)}
          fail(cert, idna)
  
          # wildcard in first fragment and  IDNA A-labels in sequent fragments
          # are supported.
          idna = 'www*.pythön.org'.encode("idna").decode("ascii")
          cert = {'subject': ((('commonName', idna),),)}
          fail(cert, 'www.pythön.org'.encode("idna").decode("ascii"))
          fail(cert, 'www1.pythön.org'.encode("idna").decode("ascii"))
          fail(cert, 'ftp.pythön.org'.encode("idna").decode("ascii"))
          fail(cert, 'pythön.org'.encode("idna").decode("ascii"))
  
          # Slightly fake real-world example
          cert = {'notAfter': 'Jun 26 21:41:46 2011 GMT',
                  'subject': ((('commonName', 'linuxfrz.org'),),),
                  'subjectAltName': (('DNS', 'linuxfr.org'),
                                     ('DNS', 'linuxfr.com'),
                                     ('othername', '<unsupported>'))}
          ok(cert, 'linuxfr.org')
          ok(cert, 'linuxfr.com')
          # Not a "DNS" entry
          fail(cert, '<unsupported>')
          # When there is a subjectAltName, commonName isn't used
          fail(cert, 'linuxfrz.org')
  
          # A pristine real-world example
          cert = {'notAfter': 'Dec 18 23:59:59 2011 GMT',
                  'subject': ((('countryName', 'US'),),
                              (('stateOrProvinceName', 'California'),),
                              (('localityName', 'Mountain View'),),
                              (('organizationName', 'Google Inc'),),
                              (('commonName', 'mail.google.com'),))}
          ok(cert, 'mail.google.com')
          fail(cert, 'gmail.com')
          # Only commonName is considered
          fail(cert, 'California')
  
          # -- IPv4 matching --
          cert = {'subject': ((('commonName', 'example.com'),),),
                  'subjectAltName': (('DNS', 'example.com'),
                                     ('IP Address', '10.11.12.13'),
                                     ('IP Address', '14.15.16.17'),
                                     ('IP Address', '127.0.0.1'))}
          ok(cert, '10.11.12.13')
          ok(cert, '14.15.16.17')
          # socket.inet_ntoa(socket.inet_aton('127.1')) == '127.0.0.1'
          fail(cert, '127.1')
          fail(cert, '14.15.16.17 ')
          fail(cert, '14.15.16.17 extra data')
          fail(cert, '14.15.16.18')
          fail(cert, 'example.net')
  
          # -- IPv6 matching --
          if support.IPV6_ENABLED:
              cert = {'subject': ((('commonName', 'example.com'),),),
                      'subjectAltName': (
                          ('DNS', 'example.com'),
                          ('IP Address', '2001:0:0:0:0:0:0:CAFE\n'),
                          ('IP Address', '2003:0:0:0:0:0:0:BABA\n'))}
              ok(cert, '2001::cafe')
              ok(cert, '2003::baba')
              fail(cert, '2003::baba ')
              fail(cert, '2003::baba extra data')
              fail(cert, '2003::bebe')
              fail(cert, 'example.net')
  
          # -- Miscellaneous --
  
          # Neither commonName nor subjectAltName
          cert = {'notAfter': 'Dec 18 23:59:59 2011 GMT',
                  'subject': ((('countryName', 'US'),),
                              (('stateOrProvinceName', 'California'),),
                              (('localityName', 'Mountain View'),),
                              (('organizationName', 'Google Inc'),))}
          fail(cert, 'mail.google.com')
  
          # No DNS entry in subjectAltName but a commonName
          cert = {'notAfter': 'Dec 18 23:59:59 2099 GMT',
                  'subject': ((('countryName', 'US'),),
                              (('stateOrProvinceName', 'California'),),
                              (('localityName', 'Mountain View'),),
                              (('commonName', 'mail.google.com'),)),
                  'subjectAltName': (('othername', 'blabla'), )}
          ok(cert, 'mail.google.com')
  
          # No DNS entry subjectAltName and no commonName
          cert = {'notAfter': 'Dec 18 23:59:59 2099 GMT',
                  'subject': ((('countryName', 'US'),),
                              (('stateOrProvinceName', 'California'),),
                              (('localityName', 'Mountain View'),),
                              (('organizationName', 'Google Inc'),)),
                  'subjectAltName': (('othername', 'blabla'),)}
          fail(cert, 'google.com')
  
          # Empty cert / no cert
          self.assertRaises(ValueError, ssl.match_hostname, None, 'example.com')
          self.assertRaises(ValueError, ssl.match_hostname, {}, 'example.com')
  
          # Issue #17980: avoid denials of service by refusing more than one
          # wildcard per fragment.
          cert = {'subject': ((('commonName', 'a*b.example.com'),),)}
          with self.assertRaisesRegex(
                  ssl.CertificateError,
                  "partial wildcards in leftmost label are not supported"):
              ssl.match_hostname(cert, 'axxb.example.com')
  
          cert = {'subject': ((('commonName', 'www.*.example.com'),),)}
          with self.assertRaisesRegex(
                  ssl.CertificateError,
                  "wildcard can only be present in the leftmost label"):
              ssl.match_hostname(cert, 'www.sub.example.com')
  
          cert = {'subject': ((('commonName', 'a*b*.example.com'),),)}
          with self.assertRaisesRegex(
                  ssl.CertificateError,
                  "too many wildcards"):
              ssl.match_hostname(cert, 'axxbxxc.example.com')
  
          cert = {'subject': ((('commonName', '*'),),)}
          with self.assertRaisesRegex(
                  ssl.CertificateError,
                  "sole wildcard without additional labels are not support"):
              ssl.match_hostname(cert, 'host')
  
          cert = {'subject': ((('commonName', '*.com'),),)}
          with self.assertRaisesRegex(
                  ssl.CertificateError,
                  r"hostname 'com' doesn't match '\*.com'"):
              ssl.match_hostname(cert, 'com')
  
          # extra checks for _inet_paton()
          for invalid in ['1', '', '1.2.3', '256.0.0.1', '127.0.0.1/24']:
              with self.assertRaises(ValueError):
                  ssl._inet_paton(invalid)
          for ipaddr in ['127.0.0.1', '192.168.0.1']:
              self.assertTrue(ssl._inet_paton(ipaddr))
          if support.IPV6_ENABLED:
              for ipaddr in ['::1', '2001:db8:85a3::8a2e:370:7334']:
                  self.assertTrue(ssl._inet_paton(ipaddr))
  
      def test_server_side(self):
          # server_hostname doesn't work for server sockets
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
          with socket.socket() as sock:
              self.assertRaises(ValueError, ctx.wrap_socket, sock, True,
                                server_hostname="some.hostname")
  
      def test_unknown_channel_binding(self):
          # should raise ValueError for unknown type
          s = socket.create_server(('127.0.0.1', 0))
          c = socket.socket(socket.AF_INET)
          c.connect(s.getsockname())
          with test_wrap_socket(c, do_handshake_on_connect=False) as ss:
              with self.assertRaises(ValueError):
                  ss.get_channel_binding("unknown-type")
          s.close()
  
      @unittest.skipUnless("tls-unique" in ssl.CHANNEL_BINDING_TYPES,
                           "'tls-unique' channel binding not available")
      def test_tls_unique_channel_binding(self):
          # unconnected should return None for known type
          s = socket.socket(socket.AF_INET)
          with test_wrap_socket(s) as ss:
              self.assertIsNone(ss.get_channel_binding("tls-unique"))
          # the same for server-side
          s = socket.socket(socket.AF_INET)
          with test_wrap_socket(s, server_side=True, certfile=CERTFILE) as ss:
              self.assertIsNone(ss.get_channel_binding("tls-unique"))
  
      def test_dealloc_warn(self):
          ss = test_wrap_socket(socket.socket(socket.AF_INET))
          r = repr(ss)
          with self.assertWarns(ResourceWarning) as cm:
              ss = None
              support.gc_collect()
          self.assertIn(r, str(cm.warning.args[0]))
  
      def test_get_default_verify_paths(self):
          paths = ssl.get_default_verify_paths()
          self.assertEqual(len(paths), 6)
          self.assertIsInstance(paths, ssl.DefaultVerifyPaths)
  
          with support.EnvironmentVarGuard() as env:
              env["SSL_CERT_DIR"] = CAPATH
              env["SSL_CERT_FILE"] = CERTFILE
              paths = ssl.get_default_verify_paths()
              self.assertEqual(paths.cafile, CERTFILE)
              self.assertEqual(paths.capath, CAPATH)
  
      @unittest.skipUnless(sys.platform == "win32", "Windows specific")
      def test_enum_certificates(self):
          self.assertTrue(ssl.enum_certificates("CA"))
          self.assertTrue(ssl.enum_certificates("ROOT"))
  
          self.assertRaises(TypeError, ssl.enum_certificates)
          self.assertRaises(WindowsError, ssl.enum_certificates, "")
  
          trust_oids = set()
          for storename in ("CA", "ROOT"):
              store = ssl.enum_certificates(storename)
              self.assertIsInstance(store, list)
              for element in store:
                  self.assertIsInstance(element, tuple)
                  self.assertEqual(len(element), 3)
                  cert, enc, trust = element
                  self.assertIsInstance(cert, bytes)
                  self.assertIn(enc, {"x509_asn", "pkcs_7_asn"})
                  self.assertIsInstance(trust, (set, bool))
                  if isinstance(trust, set):
                      trust_oids.update(trust)
  
          serverAuth = "1.3.6.1.5.5.7.3.1"
          self.assertIn(serverAuth, trust_oids)
  
      @unittest.skipUnless(sys.platform == "win32", "Windows specific")
      def test_enum_crls(self):
          self.assertTrue(ssl.enum_crls("CA"))
          self.assertRaises(TypeError, ssl.enum_crls)
          self.assertRaises(WindowsError, ssl.enum_crls, "")
  
          crls = ssl.enum_crls("CA")
          self.assertIsInstance(crls, list)
          for element in crls:
              self.assertIsInstance(element, tuple)
              self.assertEqual(len(element), 2)
              self.assertIsInstance(element[0], bytes)
              self.assertIn(element[1], {"x509_asn", "pkcs_7_asn"})
  
  
      def test_asn1object(self):
          expected = (129, 'serverAuth', 'TLS Web Server Authentication',
                      '1.3.6.1.5.5.7.3.1')
  
          val = ssl._ASN1Object('1.3.6.1.5.5.7.3.1')
          self.assertEqual(val, expected)
          self.assertEqual(val.nid, 129)
          self.assertEqual(val.shortname, 'serverAuth')
          self.assertEqual(val.longname, 'TLS Web Server Authentication')
          self.assertEqual(val.oid, '1.3.6.1.5.5.7.3.1')
          self.assertIsInstance(val, ssl._ASN1Object)
          self.assertRaises(ValueError, ssl._ASN1Object, 'serverAuth')
  
          val = ssl._ASN1Object.fromnid(129)
          self.assertEqual(val, expected)
          self.assertIsInstance(val, ssl._ASN1Object)
          self.assertRaises(ValueError, ssl._ASN1Object.fromnid, -1)
          with self.assertRaisesRegex(ValueError, "unknown NID 100000"):
              ssl._ASN1Object.fromnid(100000)
          for i in range(1000):
              try:
                  obj = ssl._ASN1Object.fromnid(i)
              except ValueError:
                  pass
              else:
                  self.assertIsInstance(obj.nid, int)
                  self.assertIsInstance(obj.shortname, str)
                  self.assertIsInstance(obj.longname, str)
                  self.assertIsInstance(obj.oid, (str, type(None)))
  
          val = ssl._ASN1Object.fromname('TLS Web Server Authentication')
          self.assertEqual(val, expected)
          self.assertIsInstance(val, ssl._ASN1Object)
          self.assertEqual(ssl._ASN1Object.fromname('serverAuth'), expected)
          self.assertEqual(ssl._ASN1Object.fromname('1.3.6.1.5.5.7.3.1'),
                           expected)
          with self.assertRaisesRegex(ValueError, "unknown object 'serverauth'"):
              ssl._ASN1Object.fromname('serverauth')
  
      def test_purpose_enum(self):
          val = ssl._ASN1Object('1.3.6.1.5.5.7.3.1')
          self.assertIsInstance(ssl.Purpose.SERVER_AUTH, ssl._ASN1Object)
          self.assertEqual(ssl.Purpose.SERVER_AUTH, val)
          self.assertEqual(ssl.Purpose.SERVER_AUTH.nid, 129)
          self.assertEqual(ssl.Purpose.SERVER_AUTH.shortname, 'serverAuth')
          self.assertEqual(ssl.Purpose.SERVER_AUTH.oid,
                                '1.3.6.1.5.5.7.3.1')
  
          val = ssl._ASN1Object('1.3.6.1.5.5.7.3.2')
          self.assertIsInstance(ssl.Purpose.CLIENT_AUTH, ssl._ASN1Object)
          self.assertEqual(ssl.Purpose.CLIENT_AUTH, val)
          self.assertEqual(ssl.Purpose.CLIENT_AUTH.nid, 130)
          self.assertEqual(ssl.Purpose.CLIENT_AUTH.shortname, 'clientAuth')
          self.assertEqual(ssl.Purpose.CLIENT_AUTH.oid,
                                '1.3.6.1.5.5.7.3.2')
  
      def test_unsupported_dtls(self):
          s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
          self.addCleanup(s.close)
          with self.assertRaises(NotImplementedError) as cx:
              test_wrap_socket(s, cert_reqs=ssl.CERT_NONE)
          self.assertEqual(str(cx.exception), "only stream sockets are supported")
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          with self.assertRaises(NotImplementedError) as cx:
              ctx.wrap_socket(s)
          self.assertEqual(str(cx.exception), "only stream sockets are supported")
  
      def cert_time_ok(self, timestring, timestamp):
          self.assertEqual(ssl.cert_time_to_seconds(timestring), timestamp)
  
      def cert_time_fail(self, timestring):
          with self.assertRaises(ValueError):
              ssl.cert_time_to_seconds(timestring)
  
      @unittest.skipUnless(utc_offset(),
                           'local time needs to be different from UTC')
      def test_cert_time_to_seconds_timezone(self):
          # Issue #19940: ssl.cert_time_to_seconds() returns wrong
          #               results if local timezone is not UTC
          self.cert_time_ok("May  9 00:00:00 2007 GMT", 1178668800.0)
          self.cert_time_ok("Jan  5 09:34:43 2018 GMT", 1515144883.0)
  
      def test_cert_time_to_seconds(self):
          timestring = "Jan  5 09:34:43 2018 GMT"
          ts = 1515144883.0
          self.cert_time_ok(timestring, ts)
          # accept keyword parameter, assert its name
          self.assertEqual(ssl.cert_time_to_seconds(cert_time=timestring), ts)
          # accept both %e and %d (space or zero generated by strftime)
          self.cert_time_ok("Jan 05 09:34:43 2018 GMT", ts)
          # case-insensitive
          self.cert_time_ok("JaN  5 09:34:43 2018 GmT", ts)
          self.cert_time_fail("Jan  5 09:34 2018 GMT")     # no seconds
          self.cert_time_fail("Jan  5 09:34:43 2018")      # no GMT
          self.cert_time_fail("Jan  5 09:34:43 2018 UTC")  # not GMT timezone
          self.cert_time_fail("Jan 35 09:34:43 2018 GMT")  # invalid day
          self.cert_time_fail("Jon  5 09:34:43 2018 GMT")  # invalid month
          self.cert_time_fail("Jan  5 24:00:00 2018 GMT")  # invalid hour
          self.cert_time_fail("Jan  5 09:60:43 2018 GMT")  # invalid minute
  
          newyear_ts = 1230768000.0
          # leap seconds
          self.cert_time_ok("Dec 31 23:59:60 2008 GMT", newyear_ts)
          # same timestamp
          self.cert_time_ok("Jan  1 00:00:00 2009 GMT", newyear_ts)
  
          self.cert_time_ok("Jan  5 09:34:59 2018 GMT", 1515144899)
          #  allow 60th second (even if it is not a leap second)
          self.cert_time_ok("Jan  5 09:34:60 2018 GMT", 1515144900)
          #  allow 2nd leap second for compatibility with time.strptime()
          self.cert_time_ok("Jan  5 09:34:61 2018 GMT", 1515144901)
          self.cert_time_fail("Jan  5 09:34:62 2018 GMT")  # invalid seconds
  
          # no special treatment for the special value:
          #   99991231235959Z (rfc 5280)
          self.cert_time_ok("Dec 31 23:59:59 9999 GMT", 253402300799.0)
  
      @support.run_with_locale('LC_ALL', '')
      def test_cert_time_to_seconds_locale(self):
          # `cert_time_to_seconds()` should be locale independent
  
          def local_february_name():
              return time.strftime('%b', (1, 2, 3, 4, 5, 6, 0, 0, 0))
  
          if local_february_name().lower() == 'feb':
              self.skipTest("locale-specific month name needs to be "
                            "different from C locale")
  
          # locale-independent
          self.cert_time_ok("Feb  9 00:00:00 2007 GMT", 1170979200.0)
          self.cert_time_fail(local_february_name() + "  9 00:00:00 2007 GMT")
  
      def test_connect_ex_error(self):
          server = socket.socket(socket.AF_INET)
          self.addCleanup(server.close)
          port = support.bind_port(server)  # Reserve port but don't listen
          s = test_wrap_socket(socket.socket(socket.AF_INET),
                              cert_reqs=ssl.CERT_REQUIRED)
          self.addCleanup(s.close)
          rc = s.connect_ex((HOST, port))
          # Issue #19919: Windows machines or VMs hosted on Windows
          # machines sometimes return EWOULDBLOCK.
          errors = (
              errno.ECONNREFUSED, errno.EHOSTUNREACH, errno.ETIMEDOUT,
              errno.EWOULDBLOCK,
          )
          self.assertIn(rc, errors)
  
  
  class ContextTests(unittest.TestCase):
  
      def test_constructor(self):
          for protocol in PROTOCOLS:
              ssl.SSLContext(protocol)
          ctx = ssl.SSLContext()
          self.assertEqual(ctx.protocol, ssl.PROTOCOL_TLS)
          self.assertRaises(ValueError, ssl.SSLContext, -1)
          self.assertRaises(ValueError, ssl.SSLContext, 42)
  
      def test_protocol(self):
          for proto in PROTOCOLS:
              ctx = ssl.SSLContext(proto)
              self.assertEqual(ctx.protocol, proto)
  
      def test_ciphers(self):
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          ctx.set_ciphers("ALL")
          ctx.set_ciphers("DEFAULT")
          with self.assertRaisesRegex(ssl.SSLError, "No cipher can be selected"):
              ctx.set_ciphers("^$:,;?*'dorothyx")
  
      @unittest.skipUnless(PY_SSL_DEFAULT_CIPHERS == 1,
                           "Test applies only to Python default ciphers")
      def test_python_ciphers(self):
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          ciphers = ctx.get_ciphers()
          for suite in ciphers:
              name = suite['name']
              self.assertNotIn("PSK", name)
              self.assertNotIn("SRP", name)
              self.assertNotIn("MD5", name)
              self.assertNotIn("RC4", name)
              self.assertNotIn("3DES", name)
  
      @unittest.skipIf(ssl.OPENSSL_VERSION_INFO < (1, 0, 2, 0, 0), 'OpenSSL too old')
      def test_get_ciphers(self):
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          ctx.set_ciphers('AESGCM')
          names = set(d['name'] for d in ctx.get_ciphers())
          self.assertIn('AES256-GCM-SHA384', names)
          self.assertIn('AES128-GCM-SHA256', names)
  
      def test_options(self):
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          # OP_ALL | OP_NO_SSLv2 | OP_NO_SSLv3 is the default value
          default = (ssl.OP_ALL | ssl.OP_NO_SSLv2 | ssl.OP_NO_SSLv3)
          # SSLContext also enables these by default
          default |= (OP_NO_COMPRESSION | OP_CIPHER_SERVER_PREFERENCE |
                      OP_SINGLE_DH_USE | OP_SINGLE_ECDH_USE |
                      OP_ENABLE_MIDDLEBOX_COMPAT)
          self.assertEqual(default, ctx.options)
          ctx.options |= ssl.OP_NO_TLSv1
          self.assertEqual(default | ssl.OP_NO_TLSv1, ctx.options)
          if can_clear_options():
              ctx.options = (ctx.options & ~ssl.OP_NO_TLSv1)
              self.assertEqual(default, ctx.options)
              ctx.options = 0
              # Ubuntu has OP_NO_SSLv3 forced on by default
              self.assertEqual(0, ctx.options & ~ssl.OP_NO_SSLv3)
          else:
              with self.assertRaises(ValueError):
                  ctx.options = 0
  
      def test_verify_mode_protocol(self):
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS)
          # Default value
          self.assertEqual(ctx.verify_mode, ssl.CERT_NONE)
          ctx.verify_mode = ssl.CERT_OPTIONAL
          self.assertEqual(ctx.verify_mode, ssl.CERT_OPTIONAL)
          ctx.verify_mode = ssl.CERT_REQUIRED
          self.assertEqual(ctx.verify_mode, ssl.CERT_REQUIRED)
          ctx.verify_mode = ssl.CERT_NONE
          self.assertEqual(ctx.verify_mode, ssl.CERT_NONE)
          with self.assertRaises(TypeError):
              ctx.verify_mode = None
          with self.assertRaises(ValueError):
              ctx.verify_mode = 42
  
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
          self.assertEqual(ctx.verify_mode, ssl.CERT_NONE)
          self.assertFalse(ctx.check_hostname)
  
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          self.assertEqual(ctx.verify_mode, ssl.CERT_REQUIRED)
          self.assertTrue(ctx.check_hostname)
  
      def test_hostname_checks_common_name(self):
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          self.assertTrue(ctx.hostname_checks_common_name)
          if ssl.HAS_NEVER_CHECK_COMMON_NAME:
              ctx.hostname_checks_common_name = True
              self.assertTrue(ctx.hostname_checks_common_name)
              ctx.hostname_checks_common_name = False
              self.assertFalse(ctx.hostname_checks_common_name)
              ctx.hostname_checks_common_name = True
              self.assertTrue(ctx.hostname_checks_common_name)
          else:
              with self.assertRaises(AttributeError):
                  ctx.hostname_checks_common_name = True
  
      @unittest.skipUnless(hasattr(ssl.SSLContext, 'minimum_version'),
                           "required OpenSSL 1.1.0g")
      def test_min_max_version(self):
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
          # OpenSSL default is MINIMUM_SUPPORTED, however some vendors like
          # Fedora override the setting to TLS 1.0.
          self.assertIn(
              ctx.minimum_version,
              {ssl.TLSVersion.MINIMUM_SUPPORTED,
               # Fedora 29 uses TLS 1.0 by default
               ssl.TLSVersion.TLSv1,
               # RHEL 8 uses TLS 1.2 by default
               ssl.TLSVersion.TLSv1_2}
          )
          self.assertEqual(
              ctx.maximum_version, ssl.TLSVersion.MAXIMUM_SUPPORTED
          )
  
          ctx.minimum_version = ssl.TLSVersion.TLSv1_1
          ctx.maximum_version = ssl.TLSVersion.TLSv1_2
          self.assertEqual(
              ctx.minimum_version, ssl.TLSVersion.TLSv1_1
          )
          self.assertEqual(
              ctx.maximum_version, ssl.TLSVersion.TLSv1_2
          )
  
          ctx.minimum_version = ssl.TLSVersion.MINIMUM_SUPPORTED
          ctx.maximum_version = ssl.TLSVersion.TLSv1
          self.assertEqual(
              ctx.minimum_version, ssl.TLSVersion.MINIMUM_SUPPORTED
          )
          self.assertEqual(
              ctx.maximum_version, ssl.TLSVersion.TLSv1
          )
  
          ctx.maximum_version = ssl.TLSVersion.MAXIMUM_SUPPORTED
          self.assertEqual(
              ctx.maximum_version, ssl.TLSVersion.MAXIMUM_SUPPORTED
          )
  
          ctx.maximum_version = ssl.TLSVersion.MINIMUM_SUPPORTED
          self.assertIn(
              ctx.maximum_version,
              {ssl.TLSVersion.TLSv1, ssl.TLSVersion.SSLv3}
          )
  
          ctx.minimum_version = ssl.TLSVersion.MAXIMUM_SUPPORTED
          self.assertIn(
              ctx.minimum_version,
              {ssl.TLSVersion.TLSv1_2, ssl.TLSVersion.TLSv1_3}
          )
  
          with self.assertRaises(ValueError):
              ctx.minimum_version = 42
  
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLSv1_1)
  
          self.assertEqual(
              ctx.minimum_version, ssl.TLSVersion.MINIMUM_SUPPORTED
          )
          self.assertEqual(
              ctx.maximum_version, ssl.TLSVersion.MAXIMUM_SUPPORTED
          )
          with self.assertRaises(ValueError):
              ctx.minimum_version = ssl.TLSVersion.MINIMUM_SUPPORTED
          with self.assertRaises(ValueError):
              ctx.maximum_version = ssl.TLSVersion.TLSv1
  
  
      @unittest.skipUnless(have_verify_flags(),
                           "verify_flags need OpenSSL > 0.9.8")
      def test_verify_flags(self):
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
          # default value
          tf = getattr(ssl, "VERIFY_X509_TRUSTED_FIRST", 0)
          self.assertEqual(ctx.verify_flags, ssl.VERIFY_DEFAULT | tf)
          ctx.verify_flags = ssl.VERIFY_CRL_CHECK_LEAF
          self.assertEqual(ctx.verify_flags, ssl.VERIFY_CRL_CHECK_LEAF)
          ctx.verify_flags = ssl.VERIFY_CRL_CHECK_CHAIN
          self.assertEqual(ctx.verify_flags, ssl.VERIFY_CRL_CHECK_CHAIN)
          ctx.verify_flags = ssl.VERIFY_DEFAULT
          self.assertEqual(ctx.verify_flags, ssl.VERIFY_DEFAULT)
          # supports any value
          ctx.verify_flags = ssl.VERIFY_CRL_CHECK_LEAF | ssl.VERIFY_X509_STRICT
          self.assertEqual(ctx.verify_flags,
                           ssl.VERIFY_CRL_CHECK_LEAF | ssl.VERIFY_X509_STRICT)
          with self.assertRaises(TypeError):
              ctx.verify_flags = None
  
      def test_load_cert_chain(self):
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
          # Combined key and cert in a single file
          ctx.load_cert_chain(CERTFILE, keyfile=None)
          ctx.load_cert_chain(CERTFILE, keyfile=CERTFILE)
          self.assertRaises(TypeError, ctx.load_cert_chain, keyfile=CERTFILE)
          with self.assertRaises(OSError) as cm:
              ctx.load_cert_chain(NONEXISTINGCERT)
          self.assertEqual(cm.exception.errno, errno.ENOENT)
          with self.assertRaisesRegex(ssl.SSLError, "PEM lib"):
              ctx.load_cert_chain(BADCERT)
          with self.assertRaisesRegex(ssl.SSLError, "PEM lib"):
              ctx.load_cert_chain(EMPTYCERT)
          # Separate key and cert
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
          ctx.load_cert_chain(ONLYCERT, ONLYKEY)
          ctx.load_cert_chain(certfile=ONLYCERT, keyfile=ONLYKEY)
          ctx.load_cert_chain(certfile=BYTES_ONLYCERT, keyfile=BYTES_ONLYKEY)
          with self.assertRaisesRegex(ssl.SSLError, "PEM lib"):
              ctx.load_cert_chain(ONLYCERT)
          with self.assertRaisesRegex(ssl.SSLError, "PEM lib"):
              ctx.load_cert_chain(ONLYKEY)
          with self.assertRaisesRegex(ssl.SSLError, "PEM lib"):
              ctx.load_cert_chain(certfile=ONLYKEY, keyfile=ONLYCERT)
          # Mismatching key and cert
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
          with self.assertRaisesRegex(ssl.SSLError, "key values mismatch"):
              ctx.load_cert_chain(CAFILE_CACERT, ONLYKEY)
          # Password protected key and cert
          ctx.load_cert_chain(CERTFILE_PROTECTED, password=KEY_PASSWORD)
          ctx.load_cert_chain(CERTFILE_PROTECTED, password=KEY_PASSWORD.encode())
          ctx.load_cert_chain(CERTFILE_PROTECTED,
                              password=bytearray(KEY_PASSWORD.encode()))
          ctx.load_cert_chain(ONLYCERT, ONLYKEY_PROTECTED, KEY_PASSWORD)
          ctx.load_cert_chain(ONLYCERT, ONLYKEY_PROTECTED, KEY_PASSWORD.encode())
          ctx.load_cert_chain(ONLYCERT, ONLYKEY_PROTECTED,
                              bytearray(KEY_PASSWORD.encode()))
          with self.assertRaisesRegex(TypeError, "should be a string"):
              ctx.load_cert_chain(CERTFILE_PROTECTED, password=True)
          with self.assertRaises(ssl.SSLError):
              ctx.load_cert_chain(CERTFILE_PROTECTED, password="badpass")
          with self.assertRaisesRegex(ValueError, "cannot be longer"):
              # openssl has a fixed limit on the password buffer.
              # PEM_BUFSIZE is generally set to 1kb.
              # Return a string larger than this.
              ctx.load_cert_chain(CERTFILE_PROTECTED, password=b'a' * 102400)
          # Password callback
          def getpass_unicode():
              return KEY_PASSWORD
          def getpass_bytes():
              return KEY_PASSWORD.encode()
          def getpass_bytearray():
              return bytearray(KEY_PASSWORD.encode())
          def getpass_badpass():
              return "badpass"
          def getpass_huge():
              return b'a' * (1024 * 1024)
          def getpass_bad_type():
              return 9
          def getpass_exception():
              raise Exception('getpass error')
          class GetPassCallable:
              def __call__(self):
                  return KEY_PASSWORD
              def getpass(self):
                  return KEY_PASSWORD
          ctx.load_cert_chain(CERTFILE_PROTECTED, password=getpass_unicode)
          ctx.load_cert_chain(CERTFILE_PROTECTED, password=getpass_bytes)
          ctx.load_cert_chain(CERTFILE_PROTECTED, password=getpass_bytearray)
          ctx.load_cert_chain(CERTFILE_PROTECTED, password=GetPassCallable())
          ctx.load_cert_chain(CERTFILE_PROTECTED,
                              password=GetPassCallable().getpass)
          with self.assertRaises(ssl.SSLError):
              ctx.load_cert_chain(CERTFILE_PROTECTED, password=getpass_badpass)
          with self.assertRaisesRegex(ValueError, "cannot be longer"):
              ctx.load_cert_chain(CERTFILE_PROTECTED, password=getpass_huge)
          with self.assertRaisesRegex(TypeError, "must return a string"):
              ctx.load_cert_chain(CERTFILE_PROTECTED, password=getpass_bad_type)
          with self.assertRaisesRegex(Exception, "getpass error"):
              ctx.load_cert_chain(CERTFILE_PROTECTED, password=getpass_exception)
          # Make sure the password function isn't called if it isn't needed
          ctx.load_cert_chain(CERTFILE, password=getpass_exception)
  
      def test_load_verify_locations(self):
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
          ctx.load_verify_locations(CERTFILE)
          ctx.load_verify_locations(cafile=CERTFILE, capath=None)
          ctx.load_verify_locations(BYTES_CERTFILE)
          ctx.load_verify_locations(cafile=BYTES_CERTFILE, capath=None)
          self.assertRaises(TypeError, ctx.load_verify_locations)
          self.assertRaises(TypeError, ctx.load_verify_locations, None, None, None)
          with self.assertRaises(OSError) as cm:
              ctx.load_verify_locations(NONEXISTINGCERT)
          self.assertEqual(cm.exception.errno, errno.ENOENT)
          with self.assertRaisesRegex(ssl.SSLError, "PEM lib"):
              ctx.load_verify_locations(BADCERT)
          ctx.load_verify_locations(CERTFILE, CAPATH)
          ctx.load_verify_locations(CERTFILE, capath=BYTES_CAPATH)
  
          # Issue #10989: crash if the second argument type is invalid
          self.assertRaises(TypeError, ctx.load_verify_locations, None, True)
  
      def test_load_verify_cadata(self):
          # test cadata
          with open(CAFILE_CACERT) as f:
              cacert_pem = f.read()
          cacert_der = ssl.PEM_cert_to_DER_cert(cacert_pem)
          with open(CAFILE_NEURONIO) as f:
              neuronio_pem = f.read()
          neuronio_der = ssl.PEM_cert_to_DER_cert(neuronio_pem)
  
          # test PEM
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          self.assertEqual(ctx.cert_store_stats()["x509_ca"], 0)
          ctx.load_verify_locations(cadata=cacert_pem)
          self.assertEqual(ctx.cert_store_stats()["x509_ca"], 1)
          ctx.load_verify_locations(cadata=neuronio_pem)
          self.assertEqual(ctx.cert_store_stats()["x509_ca"], 2)
          # cert already in hash table
          ctx.load_verify_locations(cadata=neuronio_pem)
          self.assertEqual(ctx.cert_store_stats()["x509_ca"], 2)
  
          # combined
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          combined = "\n".join((cacert_pem, neuronio_pem))
          ctx.load_verify_locations(cadata=combined)
          self.assertEqual(ctx.cert_store_stats()["x509_ca"], 2)
  
          # with junk around the certs
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          combined = ["head", cacert_pem, "other", neuronio_pem, "again",
                      neuronio_pem, "tail"]
          ctx.load_verify_locations(cadata="\n".join(combined))
          self.assertEqual(ctx.cert_store_stats()["x509_ca"], 2)
  
          # test DER
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          ctx.load_verify_locations(cadata=cacert_der)
          ctx.load_verify_locations(cadata=neuronio_der)
          self.assertEqual(ctx.cert_store_stats()["x509_ca"], 2)
          # cert already in hash table
          ctx.load_verify_locations(cadata=cacert_der)
          self.assertEqual(ctx.cert_store_stats()["x509_ca"], 2)
  
          # combined
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          combined = b"".join((cacert_der, neuronio_der))
          ctx.load_verify_locations(cadata=combined)
          self.assertEqual(ctx.cert_store_stats()["x509_ca"], 2)
  
          # error cases
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          self.assertRaises(TypeError, ctx.load_verify_locations, cadata=object)
  
          with self.assertRaisesRegex(ssl.SSLError, "no start line"):
              ctx.load_verify_locations(cadata="broken")
          with self.assertRaisesRegex(ssl.SSLError, "not enough data"):
              ctx.load_verify_locations(cadata=b"broken")
  
  
      @unittest.skipIf(Py_DEBUG_WIN32, "Avoid mixing debug/release CRT on Windows")
      def test_load_dh_params(self):
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
          ctx.load_dh_params(DHFILE)
          if os.name != 'nt':
              ctx.load_dh_params(BYTES_DHFILE)
          self.assertRaises(TypeError, ctx.load_dh_params)
          self.assertRaises(TypeError, ctx.load_dh_params, None)
          with self.assertRaises(FileNotFoundError) as cm:
              ctx.load_dh_params(NONEXISTINGCERT)
          self.assertEqual(cm.exception.errno, errno.ENOENT)
          with self.assertRaises(ssl.SSLError) as cm:
              ctx.load_dh_params(CERTFILE)
  
      def test_session_stats(self):
          for proto in PROTOCOLS:
              ctx = ssl.SSLContext(proto)
              self.assertEqual(ctx.session_stats(), {
                  'number': 0,
                  'connect': 0,
                  'connect_good': 0,
                  'connect_renegotiate': 0,
                  'accept': 0,
                  'accept_good': 0,
                  'accept_renegotiate': 0,
                  'hits': 0,
                  'misses': 0,
                  'timeouts': 0,
                  'cache_full': 0,
              })
  
      def test_set_default_verify_paths(self):
          # There's not much we can do to test that it acts as expected,
          # so just check it doesn't crash or raise an exception.
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          ctx.set_default_verify_paths()
  
      @unittest.skipUnless(ssl.HAS_ECDH, "ECDH disabled on this OpenSSL build")
      def test_set_ecdh_curve(self):
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
          ctx.set_ecdh_curve("prime256v1")
          ctx.set_ecdh_curve(b"prime256v1")
          self.assertRaises(TypeError, ctx.set_ecdh_curve)
          self.assertRaises(TypeError, ctx.set_ecdh_curve, None)
          self.assertRaises(ValueError, ctx.set_ecdh_curve, "foo")
          self.assertRaises(ValueError, ctx.set_ecdh_curve, b"foo")
  
      @needs_sni
      def test_sni_callback(self):
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
  
          # set_servername_callback expects a callable, or None
          self.assertRaises(TypeError, ctx.set_servername_callback)
          self.assertRaises(TypeError, ctx.set_servername_callback, 4)
          self.assertRaises(TypeError, ctx.set_servername_callback, "")
          self.assertRaises(TypeError, ctx.set_servername_callback, ctx)
  
          def dummycallback(sock, servername, ctx):
              pass
          ctx.set_servername_callback(None)
          ctx.set_servername_callback(dummycallback)
  
      @needs_sni
      def test_sni_callback_refcycle(self):
          # Reference cycles through the servername callback are detected
          # and cleared.
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
          def dummycallback(sock, servername, ctx, cycle=ctx):
              pass
          ctx.set_servername_callback(dummycallback)
          wr = weakref.ref(ctx)
          del ctx, dummycallback
          gc.collect()
          self.assertIs(wr(), None)
  
      def test_cert_store_stats(self):
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          self.assertEqual(ctx.cert_store_stats(),
              {'x509_ca': 0, 'crl': 0, 'x509': 0})
          ctx.load_cert_chain(CERTFILE)
          self.assertEqual(ctx.cert_store_stats(),
              {'x509_ca': 0, 'crl': 0, 'x509': 0})
          ctx.load_verify_locations(CERTFILE)
          self.assertEqual(ctx.cert_store_stats(),
              {'x509_ca': 0, 'crl': 0, 'x509': 1})
          ctx.load_verify_locations(CAFILE_CACERT)
          self.assertEqual(ctx.cert_store_stats(),
              {'x509_ca': 1, 'crl': 0, 'x509': 2})
  
      def test_get_ca_certs(self):
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          self.assertEqual(ctx.get_ca_certs(), [])
          # CERTFILE is not flagged as X509v3 Basic Constraints: CA:TRUE
          ctx.load_verify_locations(CERTFILE)
          self.assertEqual(ctx.get_ca_certs(), [])
          # but CAFILE_CACERT is a CA cert
          ctx.load_verify_locations(CAFILE_CACERT)
          self.assertEqual(ctx.get_ca_certs(),
              [{'issuer': ((('organizationName', 'Root CA'),),
                           (('organizationalUnitName', 'http://www.cacert.org'),),
                           (('commonName', 'CA Cert Signing Authority'),),
                           (('emailAddress', 'support@cacert.org'),)),
                'notAfter': asn1time('Mar 29 12:29:49 2033 GMT'),
                'notBefore': asn1time('Mar 30 12:29:49 2003 GMT'),
                'serialNumber': '00',
                'crlDistributionPoints': ('https://www.cacert.org/revoke.crl',),
                'subject': ((('organizationName', 'Root CA'),),
                            (('organizationalUnitName', 'http://www.cacert.org'),),
                            (('commonName', 'CA Cert Signing Authority'),),
                            (('emailAddress', 'support@cacert.org'),)),
                'version': 3}])
  
          with open(CAFILE_CACERT) as f:
              pem = f.read()
          der = ssl.PEM_cert_to_DER_cert(pem)
          self.assertEqual(ctx.get_ca_certs(True), [der])
  
      def test_load_default_certs(self):
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          ctx.load_default_certs()
  
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          ctx.load_default_certs(ssl.Purpose.SERVER_AUTH)
          ctx.load_default_certs()
  
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          ctx.load_default_certs(ssl.Purpose.CLIENT_AUTH)
  
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          self.assertRaises(TypeError, ctx.load_default_certs, None)
          self.assertRaises(TypeError, ctx.load_default_certs, 'SERVER_AUTH')
  
      @unittest.skipIf(sys.platform == "win32", "not-Windows specific")
      @unittest.skipIf(IS_LIBRESSL, "LibreSSL doesn't support env vars")
      def test_load_default_certs_env(self):
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          with support.EnvironmentVarGuard() as env:
              env["SSL_CERT_DIR"] = CAPATH
              env["SSL_CERT_FILE"] = CERTFILE
              ctx.load_default_certs()
              self.assertEqual(ctx.cert_store_stats(), {"crl": 0, "x509": 1, "x509_ca": 0})
  
      @unittest.skipUnless(sys.platform == "win32", "Windows specific")
      @unittest.skipIf(hasattr(sys, "gettotalrefcount"), "Debug build does not share environment between CRTs")
      def test_load_default_certs_env_windows(self):
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          ctx.load_default_certs()
          stats = ctx.cert_store_stats()
  
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          with support.EnvironmentVarGuard() as env:
              env["SSL_CERT_DIR"] = CAPATH
              env["SSL_CERT_FILE"] = CERTFILE
              ctx.load_default_certs()
              stats["x509"] += 1
              self.assertEqual(ctx.cert_store_stats(), stats)
  
      def _assert_context_options(self, ctx):
          self.assertEqual(ctx.options & ssl.OP_NO_SSLv2, ssl.OP_NO_SSLv2)
          if OP_NO_COMPRESSION != 0:
              self.assertEqual(ctx.options & OP_NO_COMPRESSION,
                               OP_NO_COMPRESSION)
          if OP_SINGLE_DH_USE != 0:
              self.assertEqual(ctx.options & OP_SINGLE_DH_USE,
                               OP_SINGLE_DH_USE)
          if OP_SINGLE_ECDH_USE != 0:
              self.assertEqual(ctx.options & OP_SINGLE_ECDH_USE,
                               OP_SINGLE_ECDH_USE)
          if OP_CIPHER_SERVER_PREFERENCE != 0:
              self.assertEqual(ctx.options & OP_CIPHER_SERVER_PREFERENCE,
                               OP_CIPHER_SERVER_PREFERENCE)
  
      def test_create_default_context(self):
          ctx = ssl.create_default_context()
  
          self.assertEqual(ctx.protocol, ssl.PROTOCOL_TLS)
          self.assertEqual(ctx.verify_mode, ssl.CERT_REQUIRED)
          self.assertTrue(ctx.check_hostname)
          self._assert_context_options(ctx)
  
          with open(SIGNING_CA) as f:
              cadata = f.read()
          ctx = ssl.create_default_context(cafile=SIGNING_CA, capath=CAPATH,
                                           cadata=cadata)
          self.assertEqual(ctx.protocol, ssl.PROTOCOL_TLS)
          self.assertEqual(ctx.verify_mode, ssl.CERT_REQUIRED)
          self._assert_context_options(ctx)
  
          ctx = ssl.create_default_context(ssl.Purpose.CLIENT_AUTH)
          self.assertEqual(ctx.protocol, ssl.PROTOCOL_TLS)
          self.assertEqual(ctx.verify_mode, ssl.CERT_NONE)
          self._assert_context_options(ctx)
  
      def test__create_stdlib_context(self):
          ctx = ssl._create_stdlib_context()
          self.assertEqual(ctx.protocol, ssl.PROTOCOL_TLS)
          self.assertEqual(ctx.verify_mode, ssl.CERT_NONE)
          self.assertFalse(ctx.check_hostname)
          self._assert_context_options(ctx)
  
          ctx = ssl._create_stdlib_context(ssl.PROTOCOL_TLSv1)
          self.assertEqual(ctx.protocol, ssl.PROTOCOL_TLSv1)
          self.assertEqual(ctx.verify_mode, ssl.CERT_NONE)
          self._assert_context_options(ctx)
  
          ctx = ssl._create_stdlib_context(ssl.PROTOCOL_TLSv1,
                                           cert_reqs=ssl.CERT_REQUIRED,
                                           check_hostname=True)
          self.assertEqual(ctx.protocol, ssl.PROTOCOL_TLSv1)
          self.assertEqual(ctx.verify_mode, ssl.CERT_REQUIRED)
          self.assertTrue(ctx.check_hostname)
          self._assert_context_options(ctx)
  
          ctx = ssl._create_stdlib_context(purpose=ssl.Purpose.CLIENT_AUTH)
          self.assertEqual(ctx.protocol, ssl.PROTOCOL_TLS)
          self.assertEqual(ctx.verify_mode, ssl.CERT_NONE)
          self._assert_context_options(ctx)
  
      def test_check_hostname(self):
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS)
          self.assertFalse(ctx.check_hostname)
          self.assertEqual(ctx.verify_mode, ssl.CERT_NONE)
  
          # Auto set CERT_REQUIRED
          ctx.check_hostname = True
          self.assertTrue(ctx.check_hostname)
          self.assertEqual(ctx.verify_mode, ssl.CERT_REQUIRED)
          ctx.check_hostname = False
          ctx.verify_mode = ssl.CERT_REQUIRED
          self.assertFalse(ctx.check_hostname)
          self.assertEqual(ctx.verify_mode, ssl.CERT_REQUIRED)
  
          # Changing verify_mode does not affect check_hostname
          ctx.check_hostname = False
          ctx.verify_mode = ssl.CERT_NONE
          ctx.check_hostname = False
          self.assertFalse(ctx.check_hostname)
          self.assertEqual(ctx.verify_mode, ssl.CERT_NONE)
          # Auto set
          ctx.check_hostname = True
          self.assertTrue(ctx.check_hostname)
          self.assertEqual(ctx.verify_mode, ssl.CERT_REQUIRED)
  
          ctx.check_hostname = False
          ctx.verify_mode = ssl.CERT_OPTIONAL
          ctx.check_hostname = False
          self.assertFalse(ctx.check_hostname)
          self.assertEqual(ctx.verify_mode, ssl.CERT_OPTIONAL)
          # keep CERT_OPTIONAL
          ctx.check_hostname = True
          self.assertTrue(ctx.check_hostname)
          self.assertEqual(ctx.verify_mode, ssl.CERT_OPTIONAL)
  
          # Cannot set CERT_NONE with check_hostname enabled
          with self.assertRaises(ValueError):
              ctx.verify_mode = ssl.CERT_NONE
          ctx.check_hostname = False
          self.assertFalse(ctx.check_hostname)
          ctx.verify_mode = ssl.CERT_NONE
          self.assertEqual(ctx.verify_mode, ssl.CERT_NONE)
  
      def test_context_client_server(self):
          # PROTOCOL_TLS_CLIENT has sane defaults
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          self.assertTrue(ctx.check_hostname)
          self.assertEqual(ctx.verify_mode, ssl.CERT_REQUIRED)
  
          # PROTOCOL_TLS_SERVER has different but also sane defaults
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
          self.assertFalse(ctx.check_hostname)
          self.assertEqual(ctx.verify_mode, ssl.CERT_NONE)
  
      def test_context_custom_class(self):
          class MySSLSocket(ssl.SSLSocket):
              pass
  
          class MySSLObject(ssl.SSLObject):
              pass
  
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
          ctx.sslsocket_class = MySSLSocket
          ctx.sslobject_class = MySSLObject
  
          with ctx.wrap_socket(socket.socket(), server_side=True) as sock:
              self.assertIsInstance(sock, MySSLSocket)
          obj = ctx.wrap_bio(ssl.MemoryBIO(), ssl.MemoryBIO())
          self.assertIsInstance(obj, MySSLObject)
  
      @unittest.skipUnless(IS_OPENSSL_1_1_1, "Test requires OpenSSL 1.1.1")
      def test_num_tickest(self):
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
          self.assertEqual(ctx.num_tickets, 2)
          ctx.num_tickets = 1
          self.assertEqual(ctx.num_tickets, 1)
          ctx.num_tickets = 0
          self.assertEqual(ctx.num_tickets, 0)
          with self.assertRaises(ValueError):
              ctx.num_tickets = -1
          with self.assertRaises(TypeError):
              ctx.num_tickets = None
  
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          self.assertEqual(ctx.num_tickets, 2)
          with self.assertRaises(ValueError):
              ctx.num_tickets = 1
  
  
  class SSLErrorTests(unittest.TestCase):
  
      def test_str(self):
          # The str() of a SSLError doesn't include the errno
          e = ssl.SSLError(1, "foo")
          self.assertEqual(str(e), "foo")
          self.assertEqual(e.errno, 1)
          # Same for a subclass
          e = ssl.SSLZeroReturnError(1, "foo")
          self.assertEqual(str(e), "foo")
          self.assertEqual(e.errno, 1)
  
      @unittest.skipIf(Py_DEBUG_WIN32, "Avoid mixing debug/release CRT on Windows")
      def test_lib_reason(self):
          # Test the library and reason attributes
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          with self.assertRaises(ssl.SSLError) as cm:
              ctx.load_dh_params(CERTFILE)
          self.assertEqual(cm.exception.library, 'PEM')
          self.assertEqual(cm.exception.reason, 'NO_START_LINE')
          s = str(cm.exception)
          self.assertTrue(s.startswith("[PEM: NO_START_LINE] no start line"), s)
  
      def test_subclass(self):
          # Check that the appropriate SSLError subclass is raised
          # (this only tests one of them)
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          ctx.check_hostname = False
          ctx.verify_mode = ssl.CERT_NONE
          with socket.create_server(("127.0.0.1", 0)) as s:
              c = socket.create_connection(s.getsockname())
              c.setblocking(False)
              with ctx.wrap_socket(c, False, do_handshake_on_connect=False) as c:
                  with self.assertRaises(ssl.SSLWantReadError) as cm:
                      c.do_handshake()
                  s = str(cm.exception)
                  self.assertTrue(s.startswith("The operation did not complete (read)"), s)
                  # For compatibility
                  self.assertEqual(cm.exception.errno, ssl.SSL_ERROR_WANT_READ)
  
  
      def test_bad_server_hostname(self):
          ctx = ssl.create_default_context()
          with self.assertRaises(ValueError):
              ctx.wrap_bio(ssl.MemoryBIO(), ssl.MemoryBIO(),
                           server_hostname="")
          with self.assertRaises(ValueError):
              ctx.wrap_bio(ssl.MemoryBIO(), ssl.MemoryBIO(),
                           server_hostname=".example.org")
          with self.assertRaises(TypeError):
              ctx.wrap_bio(ssl.MemoryBIO(), ssl.MemoryBIO(),
                           server_hostname="example.org\x00evil.com")
  
  
  class MemoryBIOTests(unittest.TestCase):
  
      def test_read_write(self):
          bio = ssl.MemoryBIO()
          bio.write(b'foo')
          self.assertEqual(bio.read(), b'foo')
          self.assertEqual(bio.read(), b'')
          bio.write(b'foo')
          bio.write(b'bar')
          self.assertEqual(bio.read(), b'foobar')
          self.assertEqual(bio.read(), b'')
          bio.write(b'baz')
          self.assertEqual(bio.read(2), b'ba')
          self.assertEqual(bio.read(1), b'z')
          self.assertEqual(bio.read(1), b'')
  
      def test_eof(self):
          bio = ssl.MemoryBIO()
          self.assertFalse(bio.eof)
          self.assertEqual(bio.read(), b'')
          self.assertFalse(bio.eof)
          bio.write(b'foo')
          self.assertFalse(bio.eof)
          bio.write_eof()
          self.assertFalse(bio.eof)
          self.assertEqual(bio.read(2), b'fo')
          self.assertFalse(bio.eof)
          self.assertEqual(bio.read(1), b'o')
          self.assertTrue(bio.eof)
          self.assertEqual(bio.read(), b'')
          self.assertTrue(bio.eof)
  
      def test_pending(self):
          bio = ssl.MemoryBIO()
          self.assertEqual(bio.pending, 0)
          bio.write(b'foo')
          self.assertEqual(bio.pending, 3)
          for i in range(3):
              bio.read(1)
              self.assertEqual(bio.pending, 3-i-1)
          for i in range(3):
              bio.write(b'x')
              self.assertEqual(bio.pending, i+1)
          bio.read()
          self.assertEqual(bio.pending, 0)
  
      def test_buffer_types(self):
          bio = ssl.MemoryBIO()
          bio.write(b'foo')
          self.assertEqual(bio.read(), b'foo')
          bio.write(bytearray(b'bar'))
          self.assertEqual(bio.read(), b'bar')
          bio.write(memoryview(b'baz'))
          self.assertEqual(bio.read(), b'baz')
  
      def test_error_types(self):
          bio = ssl.MemoryBIO()
          self.assertRaises(TypeError, bio.write, 'foo')
          self.assertRaises(TypeError, bio.write, None)
          self.assertRaises(TypeError, bio.write, True)
          self.assertRaises(TypeError, bio.write, 1)
  
  
  class SSLObjectTests(unittest.TestCase):
      def test_private_init(self):
          bio = ssl.MemoryBIO()
          with self.assertRaisesRegex(TypeError, "public constructor"):
              ssl.SSLObject(bio, bio)
  
      def test_unwrap(self):
          client_ctx, server_ctx, hostname = testing_context()
          c_in = ssl.MemoryBIO()
          c_out = ssl.MemoryBIO()
          s_in = ssl.MemoryBIO()
          s_out = ssl.MemoryBIO()
          client = client_ctx.wrap_bio(c_in, c_out, server_hostname=hostname)
          server = server_ctx.wrap_bio(s_in, s_out, server_side=True)
  
          # Loop on the handshake for a bit to get it settled
          for _ in range(5):
              try:
                  client.do_handshake()
              except ssl.SSLWantReadError:
                  pass
              if c_out.pending:
                  s_in.write(c_out.read())
              try:
                  server.do_handshake()
              except ssl.SSLWantReadError:
                  pass
              if s_out.pending:
                  c_in.write(s_out.read())
          # Now the handshakes should be complete (don't raise WantReadError)
          client.do_handshake()
          server.do_handshake()
  
          # Now if we unwrap one side unilaterally, it should send close-notify
          # and raise WantReadError:
          with self.assertRaises(ssl.SSLWantReadError):
              client.unwrap()
  
          # But server.unwrap() does not raise, because it reads the client's
          # close-notify:
          s_in.write(c_out.read())
          server.unwrap()
  
          # And now that the client gets the server's close-notify, it doesn't
          # raise either.
          c_in.write(s_out.read())
          client.unwrap()
  
  class SimpleBackgroundTests(unittest.TestCase):
      """Tests that connect to a simple server running in the background"""
  
      def setUp(self):
          server = ThreadedEchoServer(SIGNED_CERTFILE)
          self.server_addr = (HOST, server.port)
          server.__enter__()
          self.addCleanup(server.__exit__, None, None, None)
  
      def test_connect(self):
          with test_wrap_socket(socket.socket(socket.AF_INET),
                              cert_reqs=ssl.CERT_NONE) as s:
              s.connect(self.server_addr)
              self.assertEqual({}, s.getpeercert())
              self.assertFalse(s.server_side)
  
          # this should succeed because we specify the root cert
          with test_wrap_socket(socket.socket(socket.AF_INET),
                              cert_reqs=ssl.CERT_REQUIRED,
                              ca_certs=SIGNING_CA) as s:
              s.connect(self.server_addr)
              self.assertTrue(s.getpeercert())
              self.assertFalse(s.server_side)
  
      def test_connect_fail(self):
          # This should fail because we have no verification certs. Connection
          # failure crashes ThreadedEchoServer, so run this in an independent
          # test method.
          s = test_wrap_socket(socket.socket(socket.AF_INET),
                              cert_reqs=ssl.CERT_REQUIRED)
          self.addCleanup(s.close)
          self.assertRaisesRegex(ssl.SSLError, "certificate verify failed",
                                 s.connect, self.server_addr)
  
      def test_connect_ex(self):
          # Issue #11326: check connect_ex() implementation
          s = test_wrap_socket(socket.socket(socket.AF_INET),
                              cert_reqs=ssl.CERT_REQUIRED,
                              ca_certs=SIGNING_CA)
          self.addCleanup(s.close)
          self.assertEqual(0, s.connect_ex(self.server_addr))
          self.assertTrue(s.getpeercert())
  
      def test_non_blocking_connect_ex(self):
          # Issue #11326: non-blocking connect_ex() should allow handshake
          # to proceed after the socket gets ready.
          s = test_wrap_socket(socket.socket(socket.AF_INET),
                              cert_reqs=ssl.CERT_REQUIRED,
                              ca_certs=SIGNING_CA,
                              do_handshake_on_connect=False)
          self.addCleanup(s.close)
          s.setblocking(False)
          rc = s.connect_ex(self.server_addr)
          # EWOULDBLOCK under Windows, EINPROGRESS elsewhere
          self.assertIn(rc, (0, errno.EINPROGRESS, errno.EWOULDBLOCK))
          # Wait for connect to finish
          select.select([], [s], [], 5.0)
          # Non-blocking handshake
          while True:
              try:
                  s.do_handshake()
                  break
              except ssl.SSLWantReadError:
                  select.select([s], [], [], 5.0)
              except ssl.SSLWantWriteError:
                  select.select([], [s], [], 5.0)
          # SSL established
          self.assertTrue(s.getpeercert())
  
      def test_connect_with_context(self):
          # Same as test_connect, but with a separately created context
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS)
          with ctx.wrap_socket(socket.socket(socket.AF_INET)) as s:
              s.connect(self.server_addr)
              self.assertEqual({}, s.getpeercert())
          # Same with a server hostname
          with ctx.wrap_socket(socket.socket(socket.AF_INET),
                              server_hostname="dummy") as s:
              s.connect(self.server_addr)
          ctx.verify_mode = ssl.CERT_REQUIRED
          # This should succeed because we specify the root cert
          ctx.load_verify_locations(SIGNING_CA)
          with ctx.wrap_socket(socket.socket(socket.AF_INET)) as s:
              s.connect(self.server_addr)
              cert = s.getpeercert()
              self.assertTrue(cert)
  
      def test_connect_with_context_fail(self):
          # This should fail because we have no verification certs. Connection
          # failure crashes ThreadedEchoServer, so run this in an independent
          # test method.
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS)
          ctx.verify_mode = ssl.CERT_REQUIRED
          s = ctx.wrap_socket(socket.socket(socket.AF_INET))
          self.addCleanup(s.close)
          self.assertRaisesRegex(ssl.SSLError, "certificate verify failed",
                                  s.connect, self.server_addr)
  
      def test_connect_capath(self):
          # Verify server certificates using the `capath` argument
          # NOTE: the subject hashing algorithm has been changed between
          # OpenSSL 0.9.8n and 1.0.0, as a result the capath directory must
          # contain both versions of each certificate (same content, different
          # filename) for this test to be portable across OpenSSL releases.
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS)
          ctx.verify_mode = ssl.CERT_REQUIRED
          ctx.load_verify_locations(capath=CAPATH)
          with ctx.wrap_socket(socket.socket(socket.AF_INET)) as s:
              s.connect(self.server_addr)
              cert = s.getpeercert()
              self.assertTrue(cert)
  
          # Same with a bytes `capath` argument
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS)
          ctx.verify_mode = ssl.CERT_REQUIRED
          ctx.load_verify_locations(capath=BYTES_CAPATH)
          with ctx.wrap_socket(socket.socket(socket.AF_INET)) as s:
              s.connect(self.server_addr)
              cert = s.getpeercert()
              self.assertTrue(cert)
  
      def test_connect_cadata(self):
          with open(SIGNING_CA) as f:
              pem = f.read()
          der = ssl.PEM_cert_to_DER_cert(pem)
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS)
          ctx.verify_mode = ssl.CERT_REQUIRED
          ctx.load_verify_locations(cadata=pem)
          with ctx.wrap_socket(socket.socket(socket.AF_INET)) as s:
              s.connect(self.server_addr)
              cert = s.getpeercert()
              self.assertTrue(cert)
  
          # same with DER
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS)
          ctx.verify_mode = ssl.CERT_REQUIRED
          ctx.load_verify_locations(cadata=der)
          with ctx.wrap_socket(socket.socket(socket.AF_INET)) as s:
              s.connect(self.server_addr)
              cert = s.getpeercert()
              self.assertTrue(cert)
  
      @unittest.skipIf(os.name == "nt", "Can't use a socket as a file under Windows")
      def test_makefile_close(self):
          # Issue #5238: creating a file-like object with makefile() shouldn't
          # delay closing the underlying "real socket" (here tested with its
          # file descriptor, hence skipping the test under Windows).
          ss = test_wrap_socket(socket.socket(socket.AF_INET))
          ss.connect(self.server_addr)
          fd = ss.fileno()
          f = ss.makefile()
          f.close()
          # The fd is still open
          os.read(fd, 0)
          # Closing the SSL socket should close the fd too
          ss.close()
          gc.collect()
          with self.assertRaises(OSError) as e:
              os.read(fd, 0)
          self.assertEqual(e.exception.errno, errno.EBADF)
  
      def test_non_blocking_handshake(self):
          s = socket.socket(socket.AF_INET)
          s.connect(self.server_addr)
          s.setblocking(False)
          s = test_wrap_socket(s,
                              cert_reqs=ssl.CERT_NONE,
                              do_handshake_on_connect=False)
          self.addCleanup(s.close)
          count = 0
          while True:
              try:
                  count += 1
                  s.do_handshake()
                  break
              except ssl.SSLWantReadError:
                  select.select([s], [], [])
              except ssl.SSLWantWriteError:
                  select.select([], [s], [])
          if support.verbose:
              sys.stdout.write("\nNeeded %d calls to do_handshake() to establish session.\n" % count)
  
      def test_get_server_certificate(self):
          _test_get_server_certificate(self, *self.server_addr, cert=SIGNING_CA)
  
      def test_get_server_certificate_fail(self):
          # Connection failure crashes ThreadedEchoServer, so run this in an
          # independent test method
          _test_get_server_certificate_fail(self, *self.server_addr)
  
      def test_ciphers(self):
          with test_wrap_socket(socket.socket(socket.AF_INET),
                               cert_reqs=ssl.CERT_NONE, ciphers="ALL") as s:
              s.connect(self.server_addr)
          with test_wrap_socket(socket.socket(socket.AF_INET),
                               cert_reqs=ssl.CERT_NONE, ciphers="DEFAULT") as s:
              s.connect(self.server_addr)
          # Error checking can happen at instantiation or when connecting
          with self.assertRaisesRegex(ssl.SSLError, "No cipher can be selected"):
              with socket.socket(socket.AF_INET) as sock:
                  s = test_wrap_socket(sock,
                                      cert_reqs=ssl.CERT_NONE, ciphers="^$:,;?*'dorothyx")
                  s.connect(self.server_addr)
  
      def test_get_ca_certs_capath(self):
          # capath certs are loaded on request
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          ctx.load_verify_locations(capath=CAPATH)
          self.assertEqual(ctx.get_ca_certs(), [])
          with ctx.wrap_socket(socket.socket(socket.AF_INET),
                               server_hostname='localhost') as s:
              s.connect(self.server_addr)
              cert = s.getpeercert()
              self.assertTrue(cert)
          self.assertEqual(len(ctx.get_ca_certs()), 1)
  
      @needs_sni
      def test_context_setget(self):
          # Check that the context of a connected socket can be replaced.
          ctx1 = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          ctx1.load_verify_locations(capath=CAPATH)
          ctx2 = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          ctx2.load_verify_locations(capath=CAPATH)
          s = socket.socket(socket.AF_INET)
          with ctx1.wrap_socket(s, server_hostname='localhost') as ss:
              ss.connect(self.server_addr)
              self.assertIs(ss.context, ctx1)
              self.assertIs(ss._sslobj.context, ctx1)
              ss.context = ctx2
              self.assertIs(ss.context, ctx2)
              self.assertIs(ss._sslobj.context, ctx2)
  
      def ssl_io_loop(self, sock, incoming, outgoing, func, *args, **kwargs):
          # A simple IO loop. Call func(*args) depending on the error we get
          # (WANT_READ or WANT_WRITE) move data between the socket and the BIOs.
          timeout = kwargs.get('timeout', 10)
          deadline = time.monotonic() + timeout
          count = 0
          while True:
              if time.monotonic() > deadline:
                  self.fail("timeout")
              errno = None
              count += 1
              try:
                  ret = func(*args)
              except ssl.SSLError as e:
                  if e.errno not in (ssl.SSL_ERROR_WANT_READ,
                                     ssl.SSL_ERROR_WANT_WRITE):
                      raise
                  errno = e.errno
              # Get any data from the outgoing BIO irrespective of any error, and
              # send it to the socket.
              buf = outgoing.read()
              sock.sendall(buf)
              # If there's no error, we're done. For WANT_READ, we need to get
              # data from the socket and put it in the incoming BIO.
              if errno is None:
                  break
              elif errno == ssl.SSL_ERROR_WANT_READ:
                  buf = sock.recv(32768)
                  if buf:
                      incoming.write(buf)
                  else:
                      incoming.write_eof()
          if support.verbose:
              sys.stdout.write("Needed %d calls to complete %s().\n"
                               % (count, func.__name__))
          return ret
  
      def test_bio_handshake(self):
          sock = socket.socket(socket.AF_INET)
          self.addCleanup(sock.close)
          sock.connect(self.server_addr)
          incoming = ssl.MemoryBIO()
          outgoing = ssl.MemoryBIO()
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          self.assertTrue(ctx.check_hostname)
          self.assertEqual(ctx.verify_mode, ssl.CERT_REQUIRED)
          ctx.load_verify_locations(SIGNING_CA)
          sslobj = ctx.wrap_bio(incoming, outgoing, False,
                                SIGNED_CERTFILE_HOSTNAME)
          self.assertIs(sslobj._sslobj.owner, sslobj)
          self.assertIsNone(sslobj.cipher())
          self.assertIsNone(sslobj.version())
          self.assertIsNotNone(sslobj.shared_ciphers())
          self.assertRaises(ValueError, sslobj.getpeercert)
          if 'tls-unique' in ssl.CHANNEL_BINDING_TYPES:
              self.assertIsNone(sslobj.get_channel_binding('tls-unique'))
          self.ssl_io_loop(sock, incoming, outgoing, sslobj.do_handshake)
          self.assertTrue(sslobj.cipher())
          self.assertIsNotNone(sslobj.shared_ciphers())
          self.assertIsNotNone(sslobj.version())
          self.assertTrue(sslobj.getpeercert())
          if 'tls-unique' in ssl.CHANNEL_BINDING_TYPES:
              self.assertTrue(sslobj.get_channel_binding('tls-unique'))
          try:
              self.ssl_io_loop(sock, incoming, outgoing, sslobj.unwrap)
          except ssl.SSLSyscallError:
              # If the server shuts down the TCP connection without sending a
              # secure shutdown message, this is reported as SSL_ERROR_SYSCALL
              pass
          self.assertRaises(ssl.SSLError, sslobj.write, b'foo')
  
      def test_bio_read_write_data(self):
          sock = socket.socket(socket.AF_INET)
          self.addCleanup(sock.close)
          sock.connect(self.server_addr)
          incoming = ssl.MemoryBIO()
          outgoing = ssl.MemoryBIO()
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS)
          ctx.verify_mode = ssl.CERT_NONE
          sslobj = ctx.wrap_bio(incoming, outgoing, False)
          self.ssl_io_loop(sock, incoming, outgoing, sslobj.do_handshake)
          req = b'FOO\n'
          self.ssl_io_loop(sock, incoming, outgoing, sslobj.write, req)
          buf = self.ssl_io_loop(sock, incoming, outgoing, sslobj.read, 1024)
          self.assertEqual(buf, b'foo\n')
          self.ssl_io_loop(sock, incoming, outgoing, sslobj.unwrap)
  
  
  class NetworkedTests(unittest.TestCase):
  
      def test_timeout_connect_ex(self):
          # Issue #12065: on a timeout, connect_ex() should return the original
          # errno (mimicking the behaviour of non-SSL sockets).
          with support.transient_internet(REMOTE_HOST):
              s = test_wrap_socket(socket.socket(socket.AF_INET),
                                  cert_reqs=ssl.CERT_REQUIRED,
                                  do_handshake_on_connect=False)
              self.addCleanup(s.close)
              s.settimeout(0.0000001)
              rc = s.connect_ex((REMOTE_HOST, 443))
              if rc == 0:
                  self.skipTest("REMOTE_HOST responded too quickly")
              self.assertIn(rc, (errno.EAGAIN, errno.EWOULDBLOCK))
  
      @unittest.skipUnless(support.IPV6_ENABLED, 'Needs IPv6')
      def test_get_server_certificate_ipv6(self):
          with support.transient_internet('ipv6.google.com'):
              _test_get_server_certificate(self, 'ipv6.google.com', 443)
              _test_get_server_certificate_fail(self, 'ipv6.google.com', 443)
  
  
  def _test_get_server_certificate(test, host, port, cert=None):
      pem = ssl.get_server_certificate((host, port))
      if not pem:
          test.fail("No server certificate on %s:%s!" % (host, port))
  
      pem = ssl.get_server_certificate((host, port), ca_certs=cert)
      if not pem:
          test.fail("No server certificate on %s:%s!" % (host, port))
      if support.verbose:
          sys.stdout.write("\nVerified certificate for %s:%s is\n%s\n" % (host, port ,pem))
  
  def _test_get_server_certificate_fail(test, host, port):
      try:
          pem = ssl.get_server_certificate((host, port), ca_certs=CERTFILE)
      except ssl.SSLError as x:
          #should fail
          if support.verbose:
              sys.stdout.write("%s\n" % x)
      else:
          test.fail("Got server certificate %s for %s:%s!" % (pem, host, port))
  
  
  from test.ssl_servers import make_https_server
  
  class ThreadedEchoServer(threading.Thread):
  
      class ConnectionHandler(threading.Thread):
  
          """A mildly complicated class, because we want it to work both
          with and without the SSL wrapper around the socket connection, so
          that we can test the STARTTLS functionality."""
  
          def __init__(self, server, connsock, addr):
              self.server = server
              self.running = False
              self.sock = connsock
              self.addr = addr
              self.sock.setblocking(1)
              self.sslconn = None
              threading.Thread.__init__(self)
              self.daemon = True
  
          def wrap_conn(self):
              try:
                  self.sslconn = self.server.context.wrap_socket(
                      self.sock, server_side=True)
                  self.server.selected_npn_protocols.append(self.sslconn.selected_npn_protocol())
                  self.server.selected_alpn_protocols.append(self.sslconn.selected_alpn_protocol())
              except (ConnectionResetError, BrokenPipeError, ConnectionAbortedError) as e:
                  # We treat ConnectionResetError as though it were an
                  # SSLError - OpenSSL on Ubuntu abruptly closes the
                  # connection when asked to use an unsupported protocol.
                  #
                  # BrokenPipeError is raised in TLS 1.3 mode, when OpenSSL
                  # tries to send session tickets after handshake.
                  # https://github.com/openssl/openssl/issues/6342
                  #
                  # ConnectionAbortedError is raised in TLS 1.3 mode, when OpenSSL
                  # tries to send session tickets after handshake when using WinSock.
                  self.server.conn_errors.append(str(e))
                  if self.server.chatty:
                      handle_error("\n server:  bad connection attempt from " + repr(self.addr) + ":\n")
                  self.running = False
                  self.close()
                  return False
              except (ssl.SSLError, OSError) as e:
                  # OSError may occur with wrong protocols, e.g. both
                  # sides use PROTOCOL_TLS_SERVER.
                  #
                  # XXX Various errors can have happened here, for example
                  # a mismatching protocol version, an invalid certificate,
                  # or a low-level bug. This should be made more discriminating.
                  #
                  # bpo-31323: Store the exception as string to prevent
                  # a reference leak: server -> conn_errors -> exception
                  # -> traceback -> self (ConnectionHandler) -> server
                  self.server.conn_errors.append(str(e))
                  if self.server.chatty:
                      handle_error("\n server:  bad connection attempt from " + repr(self.addr) + ":\n")
                  self.running = False
                  self.server.stop()
                  self.close()
                  return False
              else:
                  self.server.shared_ciphers.append(self.sslconn.shared_ciphers())
                  if self.server.context.verify_mode == ssl.CERT_REQUIRED:
                      cert = self.sslconn.getpeercert()
                      if support.verbose and self.server.chatty:
                          sys.stdout.write(" client cert is " + pprint.pformat(cert) + "\n")
                      cert_binary = self.sslconn.getpeercert(True)
                      if support.verbose and self.server.chatty:
                          sys.stdout.write(" cert binary is " + str(len(cert_binary)) + " bytes\n")
                  cipher = self.sslconn.cipher()
                  if support.verbose and self.server.chatty:
                      sys.stdout.write(" server: connection cipher is now " + str(cipher) + "\n")
                      sys.stdout.write(" server: selected protocol is now "
                              + str(self.sslconn.selected_npn_protocol()) + "\n")
                  return True
  
          def read(self):
              if self.sslconn:
                  return self.sslconn.read()
              else:
                  return self.sock.recv(1024)
  
          def write(self, bytes):
              if self.sslconn:
                  return self.sslconn.write(bytes)
              else:
                  return self.sock.send(bytes)
  
          def close(self):
              if self.sslconn:
                  self.sslconn.close()
              else:
                  self.sock.close()
  
          def run(self):
              self.running = True
              if not self.server.starttls_server:
                  if not self.wrap_conn():
                      return
              while self.running:
                  try:
                      msg = self.read()
                      stripped = msg.strip()
                      if not stripped:
                          # eof, so quit this handler
                          self.running = False
                          try:
                              self.sock = self.sslconn.unwrap()
                          except OSError:
                              # Many tests shut the TCP connection down
                              # without an SSL shutdown. This causes
                              # unwrap() to raise OSError with errno=0!
                              pass
                          else:
                              self.sslconn = None
                          self.close()
                      elif stripped == b'over':
                          if support.verbose and self.server.connectionchatty:
                              sys.stdout.write(" server: client closed connection\n")
                          self.close()
                          return
                      elif (self.server.starttls_server and
                            stripped == b'STARTTLS'):
                          if support.verbose and self.server.connectionchatty:
                              sys.stdout.write(" server: read STARTTLS from client, sending OK...\n")
                          self.write(b"OK\n")
                          if not self.wrap_conn():
                              return
                      elif (self.server.starttls_server and self.sslconn
                            and stripped == b'ENDTLS'):
                          if support.verbose and self.server.connectionchatty:
                              sys.stdout.write(" server: read ENDTLS from client, sending OK...\n")
                          self.write(b"OK\n")
                          self.sock = self.sslconn.unwrap()
                          self.sslconn = None
                          if support.verbose and self.server.connectionchatty:
                              sys.stdout.write(" server: connection is now unencrypted...\n")
                      elif stripped == b'CB tls-unique':
                          if support.verbose and self.server.connectionchatty:
                              sys.stdout.write(" server: read CB tls-unique from client, sending our CB data...\n")
                          data = self.sslconn.get_channel_binding("tls-unique")
                          self.write(repr(data).encode("us-ascii") + b"\n")
                      elif stripped == b'PHA':
                          if support.verbose and self.server.connectionchatty:
                              sys.stdout.write(" server: initiating post handshake auth\n")
                          try:
                              self.sslconn.verify_client_post_handshake()
                          except ssl.SSLError as e:
                              self.write(repr(e).encode("us-ascii") + b"\n")
                          else:
                              self.write(b"OK\n")
                      elif stripped == b'HASCERT':
                          if self.sslconn.getpeercert() is not None:
                              self.write(b'TRUE\n')
                          else:
                              self.write(b'FALSE\n')
                      elif stripped == b'GETCERT':
                          cert = self.sslconn.getpeercert()
                          self.write(repr(cert).encode("us-ascii") + b"\n")
                      else:
                          if (support.verbose and
                              self.server.connectionchatty):
                              ctype = (self.sslconn and "encrypted") or "unencrypted"
                              sys.stdout.write(" server: read %r (%s), sending back %r (%s)...\n"
                                               % (msg, ctype, msg.lower(), ctype))
                          self.write(msg.lower())
                  except (ConnectionResetError, ConnectionAbortedError):
                      # XXX: OpenSSL 1.1.1 sometimes raises ConnectionResetError
                      # when connection is not shut down gracefully.
                      if self.server.chatty and support.verbose:
                          sys.stdout.write(
                              " Connection reset by peer: {}\n".format(
                                  self.addr)
                          )
                      self.close()
                      self.running = False
                  except ssl.SSLError as err:
                      # On Windows sometimes test_pha_required_nocert receives the
                      # PEER_DID_NOT_RETURN_A_CERTIFICATE exception
                      # before the 'tlsv13 alert certificate required' exception.
                      # If the server is stopped when PEER_DID_NOT_RETURN_A_CERTIFICATE
                      # is received test_pha_required_nocert fails with ConnectionResetError
                      # because the underlying socket is closed
                      if 'PEER_DID_NOT_RETURN_A_CERTIFICATE' == err.reason:
                          if self.server.chatty and support.verbose:
                              sys.stdout.write(err.args[1])
                          # test_pha_required_nocert is expecting this exception
                          raise ssl.SSLError('tlsv13 alert certificate required')
                  except OSError:
                      if self.server.chatty:
                          handle_error("Test server failure:\n")
                      self.close()
                      self.running = False
  
                      # normally, we'd just stop here, but for the test
                      # harness, we want to stop the server
                      self.server.stop()
  
      def __init__(self, certificate=None, ssl_version=None,
                   certreqs=None, cacerts=None,
                   chatty=True, connectionchatty=False, starttls_server=False,
                   npn_protocols=None, alpn_protocols=None,
                   ciphers=None, context=None):
          if context:
              self.context = context
          else:
              self.context = ssl.SSLContext(ssl_version
                                            if ssl_version is not None
                                            else ssl.PROTOCOL_TLS_SERVER)
              self.context.verify_mode = (certreqs if certreqs is not None
                                          else ssl.CERT_NONE)
              if cacerts:
                  self.context.load_verify_locations(cacerts)
              if certificate:
                  self.context.load_cert_chain(certificate)
              if npn_protocols:
                  self.context.set_npn_protocols(npn_protocols)
              if alpn_protocols:
                  self.context.set_alpn_protocols(alpn_protocols)
              if ciphers:
                  self.context.set_ciphers(ciphers)
          self.chatty = chatty
          self.connectionchatty = connectionchatty
          self.starttls_server = starttls_server
          self.sock = socket.socket()
          self.port = support.bind_port(self.sock)
          self.flag = None
          self.active = False
          self.selected_npn_protocols = []
          self.selected_alpn_protocols = []
          self.shared_ciphers = []
          self.conn_errors = []
          threading.Thread.__init__(self)
          self.daemon = True
  
      def __enter__(self):
          self.start(threading.Event())
          self.flag.wait()
          return self
  
      def __exit__(self, *args):
          self.stop()
          self.join()
  
      def start(self, flag=None):
          self.flag = flag
          threading.Thread.start(self)
  
      def run(self):
          self.sock.settimeout(0.05)
          self.sock.listen()
          self.active = True
          if self.flag:
              # signal an event
              self.flag.set()
          while self.active:
              try:
                  newconn, connaddr = self.sock.accept()
                  if support.verbose and self.chatty:
                      sys.stdout.write(' server:  new connection from '
                                       + repr(connaddr) + '\n')
                  handler = self.ConnectionHandler(self, newconn, connaddr)
                  handler.start()
                  handler.join()
              except socket.timeout:
                  pass
              except KeyboardInterrupt:
                  self.stop()
              except BaseException as e:
                  if support.verbose and self.chatty:
                      sys.stdout.write(
                          ' connection handling failed: ' + repr(e) + '\n')
  
          self.sock.close()
  
      def stop(self):
          self.active = False
  
  class AsyncoreEchoServer(threading.Thread):
  
      # this one's based on asyncore.dispatcher
  
      class EchoServer (asyncore.dispatcher):
  
          class ConnectionHandler(asyncore.dispatcher_with_send):
  
              def __init__(self, conn, certfile):
                  self.socket = test_wrap_socket(conn, server_side=True,
                                                certfile=certfile,
                                                do_handshake_on_connect=False)
                  asyncore.dispatcher_with_send.__init__(self, self.socket)
                  self._ssl_accepting = True
                  self._do_ssl_handshake()
  
              def readable(self):
                  if isinstance(self.socket, ssl.SSLSocket):
                      while self.socket.pending() > 0:
                          self.handle_read_event()
                  return True
  
              def _do_ssl_handshake(self):
                  try:
                      self.socket.do_handshake()
                  except (ssl.SSLWantReadError, ssl.SSLWantWriteError):
                      return
                  except ssl.SSLEOFError:
                      return self.handle_close()
                  except ssl.SSLError:
                      raise
                  except OSError as err:
                      if err.args[0] == errno.ECONNABORTED:
                          return self.handle_close()
                  else:
                      self._ssl_accepting = False
  
              def handle_read(self):
                  if self._ssl_accepting:
                      self._do_ssl_handshake()
                  else:
                      data = self.recv(1024)
                      if support.verbose:
                          sys.stdout.write(" server:  read %s from client\n" % repr(data))
                      if not data:
                          self.close()
                      else:
                          self.send(data.lower())
  
              def handle_close(self):
                  self.close()
                  if support.verbose:
                      sys.stdout.write(" server:  closed connection %s\n" % self.socket)
  
              def handle_error(self):
                  raise
  
          def __init__(self, certfile):
              self.certfile = certfile
              sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
              self.port = support.bind_port(sock, '')
              asyncore.dispatcher.__init__(self, sock)
              self.listen(5)
  
          def handle_accepted(self, sock_obj, addr):
              if support.verbose:
                  sys.stdout.write(" server:  new connection from %s:%s\n" %addr)
              self.ConnectionHandler(sock_obj, self.certfile)
  
          def handle_error(self):
              raise
  
      def __init__(self, certfile):
          self.flag = None
          self.active = False
          self.server = self.EchoServer(certfile)
          self.port = self.server.port
          threading.Thread.__init__(self)
          self.daemon = True
  
      def __str__(self):
          return "<%s %s>" % (self.__class__.__name__, self.server)
  
      def __enter__(self):
          self.start(threading.Event())
          self.flag.wait()
          return self
  
      def __exit__(self, *args):
          if support.verbose:
              sys.stdout.write(" cleanup: stopping server.\n")
          self.stop()
          if support.verbose:
              sys.stdout.write(" cleanup: joining server thread.\n")
          self.join()
          if support.verbose:
              sys.stdout.write(" cleanup: successfully joined.\n")
          # make sure that ConnectionHandler is removed from socket_map
          asyncore.close_all(ignore_all=True)
  
      def start (self, flag=None):
          self.flag = flag
          threading.Thread.start(self)
  
      def run(self):
          self.active = True
          if self.flag:
              self.flag.set()
          while self.active:
              try:
                  asyncore.loop(1)
              except:
                  pass
  
      def stop(self):
          self.active = False
          self.server.close()
  
  def server_params_test(client_context, server_context, indata=b"FOO\n",
                         chatty=True, connectionchatty=False, sni_name=None,
                         session=None):
      """
      Launch a server, connect a client to it and try various reads
      and writes.
      """
      stats = {}
      server = ThreadedEchoServer(context=server_context,
                                  chatty=chatty,
                                  connectionchatty=False)
      with server:
          with client_context.wrap_socket(socket.socket(),
                  server_hostname=sni_name, session=session) as s:
              s.connect((HOST, server.port))
              for arg in [indata, bytearray(indata), memoryview(indata)]:
                  if connectionchatty:
                      if support.verbose:
                          sys.stdout.write(
                              " client:  sending %r...\n" % indata)
                  s.write(arg)
                  outdata = s.read()
                  if connectionchatty:
                      if support.verbose:
                          sys.stdout.write(" client:  read %r\n" % outdata)
                  if outdata != indata.lower():
                      raise AssertionError(
                          "bad data <<%r>> (%d) received; expected <<%r>> (%d)\n"
                          % (outdata[:20], len(outdata),
                             indata[:20].lower(), len(indata)))
              s.write(b"over\n")
              if connectionchatty:
                  if support.verbose:
                      sys.stdout.write(" client:  closing connection.\n")
              stats.update({
                  'compression': s.compression(),
                  'cipher': s.cipher(),
                  'peercert': s.getpeercert(),
                  'client_alpn_protocol': s.selected_alpn_protocol(),
                  'client_npn_protocol': s.selected_npn_protocol(),
                  'version': s.version(),
                  'session_reused': s.session_reused,
                  'session': s.session,
              })
              s.close()
          stats['server_alpn_protocols'] = server.selected_alpn_protocols
          stats['server_npn_protocols'] = server.selected_npn_protocols
          stats['server_shared_ciphers'] = server.shared_ciphers
      return stats
  
  def try_protocol_combo(server_protocol, client_protocol, expect_success,
                         certsreqs=None, server_options=0, client_options=0):
      """
      Try to SSL-connect using *client_protocol* to *server_protocol*.
      If *expect_success* is true, assert that the connection succeeds,
      if it's false, assert that the connection fails.
      Also, if *expect_success* is a string, assert that it is the protocol
      version actually used by the connection.
      """
      if certsreqs is None:
          certsreqs = ssl.CERT_NONE
      certtype = {
          ssl.CERT_NONE: "CERT_NONE",
          ssl.CERT_OPTIONAL: "CERT_OPTIONAL",
          ssl.CERT_REQUIRED: "CERT_REQUIRED",
      }[certsreqs]
      if support.verbose:
          formatstr = (expect_success and " %s->%s %s\n") or " {%s->%s} %s\n"
          sys.stdout.write(formatstr %
                           (ssl.get_protocol_name(client_protocol),
                            ssl.get_protocol_name(server_protocol),
                            certtype))
      client_context = ssl.SSLContext(client_protocol)
      client_context.options |= client_options
      server_context = ssl.SSLContext(server_protocol)
      server_context.options |= server_options
  
      min_version = PROTOCOL_TO_TLS_VERSION.get(client_protocol, None)
      if (min_version is not None
      # SSLContext.minimum_version is only available on recent OpenSSL
      # (setter added in OpenSSL 1.1.0, getter added in OpenSSL 1.1.1)
      and hasattr(server_context, 'minimum_version')
      and server_protocol == ssl.PROTOCOL_TLS
      and server_context.minimum_version > min_version):
          # If OpenSSL configuration is strict and requires more recent TLS
          # version, we have to change the minimum to test old TLS versions.
          server_context.minimum_version = min_version
  
      # NOTE: we must enable "ALL" ciphers on the client, otherwise an
      # SSLv23 client will send an SSLv3 hello (rather than SSLv2)
      # starting from OpenSSL 1.0.0 (see issue #8322).
      if client_context.protocol == ssl.PROTOCOL_TLS:
          client_context.set_ciphers("ALL")
  
      for ctx in (client_context, server_context):
          ctx.verify_mode = certsreqs
          ctx.load_cert_chain(SIGNED_CERTFILE)
          ctx.load_verify_locations(SIGNING_CA)
      try:
          stats = server_params_test(client_context, server_context,
                                     chatty=False, connectionchatty=False)
      # Protocol mismatch can result in either an SSLError, or a
      # "Connection reset by peer" error.
      except ssl.SSLError:
          if expect_success:
              raise
      except OSError as e:
          if expect_success or e.errno != errno.ECONNRESET:
              raise
      else:
          if not expect_success:
              raise AssertionError(
                  "Client protocol %s succeeded with server protocol %s!"
                  % (ssl.get_protocol_name(client_protocol),
                     ssl.get_protocol_name(server_protocol)))
          elif (expect_success is not True
                and expect_success != stats['version']):
              raise AssertionError("version mismatch: expected %r, got %r"
                                   % (expect_success, stats['version']))
  
  
  class ThreadedTests(unittest.TestCase):
  
      def test_echo(self):
          """Basic test of an SSL client connecting to a server"""
          if support.verbose:
              sys.stdout.write("\n")
          for protocol in PROTOCOLS:
              if protocol in {ssl.PROTOCOL_TLS_CLIENT, ssl.PROTOCOL_TLS_SERVER}:
                  continue
              with self.subTest(protocol=ssl._PROTOCOL_NAMES[protocol]):
                  context = ssl.SSLContext(protocol)
                  context.load_cert_chain(CERTFILE)
                  server_params_test(context, context,
                                     chatty=True, connectionchatty=True)
  
          client_context, server_context, hostname = testing_context()
  
          with self.subTest(client=ssl.PROTOCOL_TLS_CLIENT, server=ssl.PROTOCOL_TLS_SERVER):
              server_params_test(client_context=client_context,
                                 server_context=server_context,
                                 chatty=True, connectionchatty=True,
                                 sni_name=hostname)
  
          client_context.check_hostname = False
          with self.subTest(client=ssl.PROTOCOL_TLS_SERVER, server=ssl.PROTOCOL_TLS_CLIENT):
              with self.assertRaises(ssl.SSLError) as e:
                  server_params_test(client_context=server_context,
                                     server_context=client_context,
                                     chatty=True, connectionchatty=True,
                                     sni_name=hostname)
              self.assertIn('called a function you should not call',
                            str(e.exception))
  
          with self.subTest(client=ssl.PROTOCOL_TLS_SERVER, server=ssl.PROTOCOL_TLS_SERVER):
              with self.assertRaises(ssl.SSLError) as e:
                  server_params_test(client_context=server_context,
                                     server_context=server_context,
                                     chatty=True, connectionchatty=True)
              self.assertIn('called a function you should not call',
                            str(e.exception))
  
          with self.subTest(client=ssl.PROTOCOL_TLS_CLIENT, server=ssl.PROTOCOL_TLS_CLIENT):
              with self.assertRaises(ssl.SSLError) as e:
                  server_params_test(client_context=server_context,
                                     server_context=client_context,
                                     chatty=True, connectionchatty=True)
              self.assertIn('called a function you should not call',
                            str(e.exception))
  
      def test_getpeercert(self):
          if support.verbose:
              sys.stdout.write("\n")
  
          client_context, server_context, hostname = testing_context()
          server = ThreadedEchoServer(context=server_context, chatty=False)
          with server:
              with client_context.wrap_socket(socket.socket(),
                                              do_handshake_on_connect=False,
                                              server_hostname=hostname) as s:
                  s.connect((HOST, server.port))
                  # getpeercert() raise ValueError while the handshake isn't
                  # done.
                  with self.assertRaises(ValueError):
                      s.getpeercert()
                  s.do_handshake()
                  cert = s.getpeercert()
                  self.assertTrue(cert, "Can't get peer certificate.")
                  cipher = s.cipher()
                  if support.verbose:
                      sys.stdout.write(pprint.pformat(cert) + '\n')
                      sys.stdout.write("Connection cipher is " + str(cipher) + '.\n')
                  if 'subject' not in cert:
                      self.fail("No subject field in certificate: %s." %
                                pprint.pformat(cert))
                  if ((('organizationName', 'Python Software Foundation'),)
                      not in cert['subject']):
                      self.fail(
                          "Missing or invalid 'organizationName' field in certificate subject; "
                          "should be 'Python Software Foundation'.")
                  self.assertIn('notBefore', cert)
                  self.assertIn('notAfter', cert)
                  before = ssl.cert_time_to_seconds(cert['notBefore'])
                  after = ssl.cert_time_to_seconds(cert['notAfter'])
                  self.assertLess(before, after)
  
      @unittest.skipUnless(have_verify_flags(),
                          "verify_flags need OpenSSL > 0.9.8")
      def test_crl_check(self):
          if support.verbose:
              sys.stdout.write("\n")
  
          client_context, server_context, hostname = testing_context()
  
          tf = getattr(ssl, "VERIFY_X509_TRUSTED_FIRST", 0)
          self.assertEqual(client_context.verify_flags, ssl.VERIFY_DEFAULT | tf)
  
          # VERIFY_DEFAULT should pass
          server = ThreadedEchoServer(context=server_context, chatty=True)
          with server:
              with client_context.wrap_socket(socket.socket(),
                                              server_hostname=hostname) as s:
                  s.connect((HOST, server.port))
                  cert = s.getpeercert()
                  self.assertTrue(cert, "Can't get peer certificate.")
  
          # VERIFY_CRL_CHECK_LEAF without a loaded CRL file fails
          client_context.verify_flags |= ssl.VERIFY_CRL_CHECK_LEAF
  
          server = ThreadedEchoServer(context=server_context, chatty=True)
          with server:
              with client_context.wrap_socket(socket.socket(),
                                              server_hostname=hostname) as s:
                  with self.assertRaisesRegex(ssl.SSLError,
                                              "certificate verify failed"):
                      s.connect((HOST, server.port))
  
          # now load a CRL file. The CRL file is signed by the CA.
          client_context.load_verify_locations(CRLFILE)
  
          server = ThreadedEchoServer(context=server_context, chatty=True)
          with server:
              with client_context.wrap_socket(socket.socket(),
                                              server_hostname=hostname) as s:
                  s.connect((HOST, server.port))
                  cert = s.getpeercert()
                  self.assertTrue(cert, "Can't get peer certificate.")
  
      def test_check_hostname(self):
          if support.verbose:
              sys.stdout.write("\n")
  
          client_context, server_context, hostname = testing_context()
  
          # correct hostname should verify
          server = ThreadedEchoServer(context=server_context, chatty=True)
          with server:
              with client_context.wrap_socket(socket.socket(),
                                              server_hostname=hostname) as s:
                  s.connect((HOST, server.port))
                  cert = s.getpeercert()
                  self.assertTrue(cert, "Can't get peer certificate.")
  
          # incorrect hostname should raise an exception
          server = ThreadedEchoServer(context=server_context, chatty=True)
          with server:
              with client_context.wrap_socket(socket.socket(),
                                              server_hostname="invalid") as s:
                  with self.assertRaisesRegex(
                          ssl.CertificateError,
                          "Hostname mismatch, certificate is not valid for 'invalid'."):
                      s.connect((HOST, server.port))
  
          # missing server_hostname arg should cause an exception, too
          server = ThreadedEchoServer(context=server_context, chatty=True)
          with server:
              with socket.socket() as s:
                  with self.assertRaisesRegex(ValueError,
                                              "check_hostname requires server_hostname"):
                      client_context.wrap_socket(s)
  
      def test_ecc_cert(self):
          client_context = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          client_context.load_verify_locations(SIGNING_CA)
          client_context.set_ciphers('ECDHE:ECDSA:!NULL:!aRSA')
          hostname = SIGNED_CERTFILE_ECC_HOSTNAME
  
          server_context = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
          # load ECC cert
          server_context.load_cert_chain(SIGNED_CERTFILE_ECC)
  
          # correct hostname should verify
          server = ThreadedEchoServer(context=server_context, chatty=True)
          with server:
              with client_context.wrap_socket(socket.socket(),
                                              server_hostname=hostname) as s:
                  s.connect((HOST, server.port))
                  cert = s.getpeercert()
                  self.assertTrue(cert, "Can't get peer certificate.")
                  cipher = s.cipher()[0].split('-')
                  self.assertTrue(cipher[:2], ('ECDHE', 'ECDSA'))
  
      def test_dual_rsa_ecc(self):
          client_context = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          client_context.load_verify_locations(SIGNING_CA)
          # TODO: fix TLSv1.3 once SSLContext can restrict signature
          #       algorithms.
          client_context.options |= ssl.OP_NO_TLSv1_3
          # only ECDSA certs
          client_context.set_ciphers('ECDHE:ECDSA:!NULL:!aRSA')
          hostname = SIGNED_CERTFILE_ECC_HOSTNAME
  
          server_context = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
          # load ECC and RSA key/cert pairs
          server_context.load_cert_chain(SIGNED_CERTFILE_ECC)
          server_context.load_cert_chain(SIGNED_CERTFILE)
  
          # correct hostname should verify
          server = ThreadedEchoServer(context=server_context, chatty=True)
          with server:
              with client_context.wrap_socket(socket.socket(),
                                              server_hostname=hostname) as s:
                  s.connect((HOST, server.port))
                  cert = s.getpeercert()
                  self.assertTrue(cert, "Can't get peer certificate.")
                  cipher = s.cipher()[0].split('-')
                  self.assertTrue(cipher[:2], ('ECDHE', 'ECDSA'))
  
      def test_check_hostname_idn(self):
          if support.verbose:
              sys.stdout.write("\n")
  
          server_context = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
          server_context.load_cert_chain(IDNSANSFILE)
  
          context = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          context.verify_mode = ssl.CERT_REQUIRED
          context.check_hostname = True
          context.load_verify_locations(SIGNING_CA)
  
          # correct hostname should verify, when specified in several
          # different ways
          idn_hostnames = [
              ('könig.idn.pythontest.net',
               'xn--knig-5qa.idn.pythontest.net'),
              ('xn--knig-5qa.idn.pythontest.net',
               'xn--knig-5qa.idn.pythontest.net'),
              (b'xn--knig-5qa.idn.pythontest.net',
               'xn--knig-5qa.idn.pythontest.net'),
  
              ('königsgäßchen.idna2003.pythontest.net',
               'xn--knigsgsschen-lcb0w.idna2003.pythontest.net'),
              ('xn--knigsgsschen-lcb0w.idna2003.pythontest.net',
               'xn--knigsgsschen-lcb0w.idna2003.pythontest.net'),
              (b'xn--knigsgsschen-lcb0w.idna2003.pythontest.net',
               'xn--knigsgsschen-lcb0w.idna2003.pythontest.net'),
  
              # ('königsgäßchen.idna2008.pythontest.net',
              #  'xn--knigsgchen-b4a3dun.idna2008.pythontest.net'),
              ('xn--knigsgchen-b4a3dun.idna2008.pythontest.net',
               'xn--knigsgchen-b4a3dun.idna2008.pythontest.net'),
              (b'xn--knigsgchen-b4a3dun.idna2008.pythontest.net',
               'xn--knigsgchen-b4a3dun.idna2008.pythontest.net'),
  
          ]
          for server_hostname, expected_hostname in idn_hostnames:
              server = ThreadedEchoServer(context=server_context, chatty=True)
              with server:
                  with context.wrap_socket(socket.socket(),
                                           server_hostname=server_hostname) as s:
                      self.assertEqual(s.server_hostname, expected_hostname)
                      s.connect((HOST, server.port))
                      cert = s.getpeercert()
                      self.assertEqual(s.server_hostname, expected_hostname)
                      self.assertTrue(cert, "Can't get peer certificate.")
  
          # incorrect hostname should raise an exception
          server = ThreadedEchoServer(context=server_context, chatty=True)
          with server:
              with context.wrap_socket(socket.socket(),
                                       server_hostname="python.example.org") as s:
                  with self.assertRaises(ssl.CertificateError):
                      s.connect((HOST, server.port))
  
      def test_wrong_cert_tls12(self):
          """Connecting when the server rejects the client's certificate
  
          Launch a server with CERT_REQUIRED, and check that trying to
          connect to it with a wrong client certificate fails.
          """
          client_context, server_context, hostname = testing_context()
          # load client cert that is not signed by trusted CA
          client_context.load_cert_chain(CERTFILE)
          # require TLS client authentication
          server_context.verify_mode = ssl.CERT_REQUIRED
          # TLS 1.3 has different handshake
          client_context.maximum_version = ssl.TLSVersion.TLSv1_2
  
          server = ThreadedEchoServer(
              context=server_context, chatty=True, connectionchatty=True,
          )
  
          with server, \
                  client_context.wrap_socket(socket.socket(),
                                             server_hostname=hostname) as s:
              try:
                  # Expect either an SSL error about the server rejecting
                  # the connection, or a low-level connection reset (which
                  # sometimes happens on Windows)
                  s.connect((HOST, server.port))
              except ssl.SSLError as e:
                  if support.verbose:
                      sys.stdout.write("\nSSLError is %r\n" % e)
              except OSError as e:
                  if e.errno != errno.ECONNRESET:
                      raise
                  if support.verbose:
                      sys.stdout.write("\nsocket.error is %r\n" % e)
              else:
                  self.fail("Use of invalid cert should have failed!")
  
      @unittest.skipUnless(ssl.HAS_TLSv1_3, "Test needs TLS 1.3")
      def test_wrong_cert_tls13(self):
          client_context, server_context, hostname = testing_context()
          # load client cert that is not signed by trusted CA
          client_context.load_cert_chain(CERTFILE)
          server_context.verify_mode = ssl.CERT_REQUIRED
          server_context.minimum_version = ssl.TLSVersion.TLSv1_3
          client_context.minimum_version = ssl.TLSVersion.TLSv1_3
  
          server = ThreadedEchoServer(
              context=server_context, chatty=True, connectionchatty=True,
          )
          with server, \
               client_context.wrap_socket(socket.socket(),
                                          server_hostname=hostname) as s:
              # TLS 1.3 perform client cert exchange after handshake
              s.connect((HOST, server.port))
              try:
                  s.write(b'data')
                  s.read(4)
              except ssl.SSLError as e:
                  if support.verbose:
                      sys.stdout.write("\nSSLError is %r\n" % e)
              except OSError as e:
                  if e.errno != errno.ECONNRESET:
                      raise
                  if support.verbose:
                      sys.stdout.write("\nsocket.error is %r\n" % e)
              else:
                  self.fail("Use of invalid cert should have failed!")
  
      def test_rude_shutdown(self):
          """A brutal shutdown of an SSL server should raise an OSError
          in the client when attempting handshake.
          """
          listener_ready = threading.Event()
          listener_gone = threading.Event()
  
          s = socket.socket()
          port = support.bind_port(s, HOST)
  
          # `listener` runs in a thread.  It sits in an accept() until
          # the main thread connects.  Then it rudely closes the socket,
          # and sets Event `listener_gone` to let the main thread know
          # the socket is gone.
          def listener():
              s.listen()
              listener_ready.set()
              newsock, addr = s.accept()
              newsock.close()
              s.close()
              listener_gone.set()
  
          def connector():
              listener_ready.wait()
              with socket.socket() as c:
                  c.connect((HOST, port))
                  listener_gone.wait()
                  try:
                      ssl_sock = test_wrap_socket(c)
                  except OSError:
                      pass
                  else:
                      self.fail('connecting to closed SSL socket should have failed')
  
          t = threading.Thread(target=listener)
          t.start()
          try:
              connector()
          finally:
              t.join()
  
      def test_ssl_cert_verify_error(self):
          if support.verbose:
              sys.stdout.write("\n")
  
          server_context = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
          server_context.load_cert_chain(SIGNED_CERTFILE)
  
          context = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
  
          server = ThreadedEchoServer(context=server_context, chatty=True)
          with server:
              with context.wrap_socket(socket.socket(),
                                       server_hostname=SIGNED_CERTFILE_HOSTNAME) as s:
                  try:
                      s.connect((HOST, server.port))
                  except ssl.SSLError as e:
                      msg = 'unable to get local issuer certificate'
                      self.assertIsInstance(e, ssl.SSLCertVerificationError)
                      self.assertEqual(e.verify_code, 20)
                      self.assertEqual(e.verify_message, msg)
                      self.assertIn(msg, repr(e))
                      self.assertIn('certificate verify failed', repr(e))
  
      @unittest.skipUnless(hasattr(ssl, 'PROTOCOL_SSLv2'),
                           "OpenSSL is compiled without SSLv2 support")
      def test_protocol_sslv2(self):
          """Connecting to an SSLv2 server with various client options"""
          if support.verbose:
              sys.stdout.write("\n")
          try_protocol_combo(ssl.PROTOCOL_SSLv2, ssl.PROTOCOL_SSLv2, True)
          try_protocol_combo(ssl.PROTOCOL_SSLv2, ssl.PROTOCOL_SSLv2, True, ssl.CERT_OPTIONAL)
          try_protocol_combo(ssl.PROTOCOL_SSLv2, ssl.PROTOCOL_SSLv2, True, ssl.CERT_REQUIRED)
          try_protocol_combo(ssl.PROTOCOL_SSLv2, ssl.PROTOCOL_TLS, False)
          if hasattr(ssl, 'PROTOCOL_SSLv3'):
              try_protocol_combo(ssl.PROTOCOL_SSLv2, ssl.PROTOCOL_SSLv3, False)
          try_protocol_combo(ssl.PROTOCOL_SSLv2, ssl.PROTOCOL_TLSv1, False)
          # SSLv23 client with specific SSL options
          if no_sslv2_implies_sslv3_hello():
              # No SSLv2 => client will use an SSLv3 hello on recent OpenSSLs
              try_protocol_combo(ssl.PROTOCOL_SSLv2, ssl.PROTOCOL_TLS, False,
                                 client_options=ssl.OP_NO_SSLv2)
          try_protocol_combo(ssl.PROTOCOL_SSLv2, ssl.PROTOCOL_TLS, False,
                             client_options=ssl.OP_NO_SSLv3)
          try_protocol_combo(ssl.PROTOCOL_SSLv2, ssl.PROTOCOL_TLS, False,
                             client_options=ssl.OP_NO_TLSv1)
  
      def test_PROTOCOL_TLS(self):
          """Connecting to an SSLv23 server with various client options"""
          if support.verbose:
              sys.stdout.write("\n")
          if hasattr(ssl, 'PROTOCOL_SSLv2'):
              try:
                  try_protocol_combo(ssl.PROTOCOL_TLS, ssl.PROTOCOL_SSLv2, True)
              except OSError as x:
                  # this fails on some older versions of OpenSSL (0.9.7l, for instance)
                  if support.verbose:
                      sys.stdout.write(
                          " SSL2 client to SSL23 server test unexpectedly failed:\n %s\n"
                          % str(x))
          if hasattr(ssl, 'PROTOCOL_SSLv3'):
              try_protocol_combo(ssl.PROTOCOL_TLS, ssl.PROTOCOL_SSLv3, False)
          try_protocol_combo(ssl.PROTOCOL_TLS, ssl.PROTOCOL_TLS, True)
          try_protocol_combo(ssl.PROTOCOL_TLS, ssl.PROTOCOL_TLSv1, 'TLSv1')
  
          if hasattr(ssl, 'PROTOCOL_SSLv3'):
              try_protocol_combo(ssl.PROTOCOL_TLS, ssl.PROTOCOL_SSLv3, False, ssl.CERT_OPTIONAL)
          try_protocol_combo(ssl.PROTOCOL_TLS, ssl.PROTOCOL_TLS, True, ssl.CERT_OPTIONAL)
          try_protocol_combo(ssl.PROTOCOL_TLS, ssl.PROTOCOL_TLSv1, 'TLSv1', ssl.CERT_OPTIONAL)
  
          if hasattr(ssl, 'PROTOCOL_SSLv3'):
              try_protocol_combo(ssl.PROTOCOL_TLS, ssl.PROTOCOL_SSLv3, False, ssl.CERT_REQUIRED)
          try_protocol_combo(ssl.PROTOCOL_TLS, ssl.PROTOCOL_TLS, True, ssl.CERT_REQUIRED)
          try_protocol_combo(ssl.PROTOCOL_TLS, ssl.PROTOCOL_TLSv1, 'TLSv1', ssl.CERT_REQUIRED)
  
          # Server with specific SSL options
          if hasattr(ssl, 'PROTOCOL_SSLv3'):
              try_protocol_combo(ssl.PROTOCOL_TLS, ssl.PROTOCOL_SSLv3, False,
                             server_options=ssl.OP_NO_SSLv3)
          # Will choose TLSv1
          try_protocol_combo(ssl.PROTOCOL_TLS, ssl.PROTOCOL_TLS, True,
                             server_options=ssl.OP_NO_SSLv2 | ssl.OP_NO_SSLv3)
          try_protocol_combo(ssl.PROTOCOL_TLS, ssl.PROTOCOL_TLSv1, False,
                             server_options=ssl.OP_NO_TLSv1)
  
  
      @unittest.skipUnless(hasattr(ssl, 'PROTOCOL_SSLv3'),
                           "OpenSSL is compiled without SSLv3 support")
      def test_protocol_sslv3(self):
          """Connecting to an SSLv3 server with various client options"""
          if support.verbose:
              sys.stdout.write("\n")
          try_protocol_combo(ssl.PROTOCOL_SSLv3, ssl.PROTOCOL_SSLv3, 'SSLv3')
          try_protocol_combo(ssl.PROTOCOL_SSLv3, ssl.PROTOCOL_SSLv3, 'SSLv3', ssl.CERT_OPTIONAL)
          try_protocol_combo(ssl.PROTOCOL_SSLv3, ssl.PROTOCOL_SSLv3, 'SSLv3', ssl.CERT_REQUIRED)
          if hasattr(ssl, 'PROTOCOL_SSLv2'):
              try_protocol_combo(ssl.PROTOCOL_SSLv3, ssl.PROTOCOL_SSLv2, False)
          try_protocol_combo(ssl.PROTOCOL_SSLv3, ssl.PROTOCOL_TLS, False,
                             client_options=ssl.OP_NO_SSLv3)
          try_protocol_combo(ssl.PROTOCOL_SSLv3, ssl.PROTOCOL_TLSv1, False)
          if no_sslv2_implies_sslv3_hello():
              # No SSLv2 => client will use an SSLv3 hello on recent OpenSSLs
              try_protocol_combo(ssl.PROTOCOL_SSLv3, ssl.PROTOCOL_TLS,
                                 False, client_options=ssl.OP_NO_SSLv2)
  
      def test_protocol_tlsv1(self):
          """Connecting to a TLSv1 server with various client options"""
          if support.verbose:
              sys.stdout.write("\n")
          try_protocol_combo(ssl.PROTOCOL_TLSv1, ssl.PROTOCOL_TLSv1, 'TLSv1')
          try_protocol_combo(ssl.PROTOCOL_TLSv1, ssl.PROTOCOL_TLSv1, 'TLSv1', ssl.CERT_OPTIONAL)
          try_protocol_combo(ssl.PROTOCOL_TLSv1, ssl.PROTOCOL_TLSv1, 'TLSv1', ssl.CERT_REQUIRED)
          if hasattr(ssl, 'PROTOCOL_SSLv2'):
              try_protocol_combo(ssl.PROTOCOL_TLSv1, ssl.PROTOCOL_SSLv2, False)
          if hasattr(ssl, 'PROTOCOL_SSLv3'):
              try_protocol_combo(ssl.PROTOCOL_TLSv1, ssl.PROTOCOL_SSLv3, False)
          try_protocol_combo(ssl.PROTOCOL_TLSv1, ssl.PROTOCOL_TLS, False,
                             client_options=ssl.OP_NO_TLSv1)
  
      @unittest.skipUnless(hasattr(ssl, "PROTOCOL_TLSv1_1"),
                           "TLS version 1.1 not supported.")
      def test_protocol_tlsv1_1(self):
          """Connecting to a TLSv1.1 server with various client options.
             Testing against older TLS versions."""
          if support.verbose:
              sys.stdout.write("\n")
          try_protocol_combo(ssl.PROTOCOL_TLSv1_1, ssl.PROTOCOL_TLSv1_1, 'TLSv1.1')
          if hasattr(ssl, 'PROTOCOL_SSLv2'):
              try_protocol_combo(ssl.PROTOCOL_TLSv1_1, ssl.PROTOCOL_SSLv2, False)
          if hasattr(ssl, 'PROTOCOL_SSLv3'):
              try_protocol_combo(ssl.PROTOCOL_TLSv1_1, ssl.PROTOCOL_SSLv3, False)
          try_protocol_combo(ssl.PROTOCOL_TLSv1_1, ssl.PROTOCOL_TLS, False,
                             client_options=ssl.OP_NO_TLSv1_1)
  
          try_protocol_combo(ssl.PROTOCOL_TLS, ssl.PROTOCOL_TLSv1_1, 'TLSv1.1')
          try_protocol_combo(ssl.PROTOCOL_TLSv1_1, ssl.PROTOCOL_TLSv1, False)
          try_protocol_combo(ssl.PROTOCOL_TLSv1, ssl.PROTOCOL_TLSv1_1, False)
  
      @unittest.skipUnless(hasattr(ssl, "PROTOCOL_TLSv1_2"),
                           "TLS version 1.2 not supported.")
      def test_protocol_tlsv1_2(self):
          """Connecting to a TLSv1.2 server with various client options.
             Testing against older TLS versions."""
          if support.verbose:
              sys.stdout.write("\n")
          try_protocol_combo(ssl.PROTOCOL_TLSv1_2, ssl.PROTOCOL_TLSv1_2, 'TLSv1.2',
                             server_options=ssl.OP_NO_SSLv3|ssl.OP_NO_SSLv2,
                             client_options=ssl.OP_NO_SSLv3|ssl.OP_NO_SSLv2,)
          if hasattr(ssl, 'PROTOCOL_SSLv2'):
              try_protocol_combo(ssl.PROTOCOL_TLSv1_2, ssl.PROTOCOL_SSLv2, False)
          if hasattr(ssl, 'PROTOCOL_SSLv3'):
              try_protocol_combo(ssl.PROTOCOL_TLSv1_2, ssl.PROTOCOL_SSLv3, False)
          try_protocol_combo(ssl.PROTOCOL_TLSv1_2, ssl.PROTOCOL_TLS, False,
                             client_options=ssl.OP_NO_TLSv1_2)
  
          try_protocol_combo(ssl.PROTOCOL_TLS, ssl.PROTOCOL_TLSv1_2, 'TLSv1.2')
          try_protocol_combo(ssl.PROTOCOL_TLSv1_2, ssl.PROTOCOL_TLSv1, False)
          try_protocol_combo(ssl.PROTOCOL_TLSv1, ssl.PROTOCOL_TLSv1_2, False)
          try_protocol_combo(ssl.PROTOCOL_TLSv1_2, ssl.PROTOCOL_TLSv1_1, False)
          try_protocol_combo(ssl.PROTOCOL_TLSv1_1, ssl.PROTOCOL_TLSv1_2, False)
  
      def test_starttls(self):
          """Switching from clear text to encrypted and back again."""
          msgs = (b"msg 1", b"MSG 2", b"STARTTLS", b"MSG 3", b"msg 4", b"ENDTLS", b"msg 5", b"msg 6")
  
          server = ThreadedEchoServer(CERTFILE,
                                      starttls_server=True,
                                      chatty=True,
                                      connectionchatty=True)
          wrapped = False
          with server:
              s = socket.socket()
              s.setblocking(1)
              s.connect((HOST, server.port))
              if support.verbose:
                  sys.stdout.write("\n")
              for indata in msgs:
                  if support.verbose:
                      sys.stdout.write(
                          " client:  sending %r...\n" % indata)
                  if wrapped:
                      conn.write(indata)
                      outdata = conn.read()
                  else:
                      s.send(indata)
                      outdata = s.recv(1024)
                  msg = outdata.strip().lower()
                  if indata == b"STARTTLS" and msg.startswith(b"ok"):
                      # STARTTLS ok, switch to secure mode
                      if support.verbose:
                          sys.stdout.write(
                              " client:  read %r from server, starting TLS...\n"
                              % msg)
                      conn = test_wrap_socket(s)
                      wrapped = True
                  elif indata == b"ENDTLS" and msg.startswith(b"ok"):
                      # ENDTLS ok, switch back to clear text
                      if support.verbose:
                          sys.stdout.write(
                              " client:  read %r from server, ending TLS...\n"
                              % msg)
                      s = conn.unwrap()
                      wrapped = False
                  else:
                      if support.verbose:
                          sys.stdout.write(
                              " client:  read %r from server\n" % msg)
              if support.verbose:
                  sys.stdout.write(" client:  closing connection.\n")
              if wrapped:
                  conn.write(b"over\n")
              else:
                  s.send(b"over\n")
              if wrapped:
                  conn.close()
              else:
                  s.close()
  
      def test_socketserver(self):
          """Using socketserver to create and manage SSL connections."""
          server = make_https_server(self, certfile=SIGNED_CERTFILE)
          # try to connect
          if support.verbose:
              sys.stdout.write('\n')
          with open(CERTFILE, 'rb') as f:
              d1 = f.read()
          d2 = ''
          # now fetch the same data from the HTTPS server
          url = 'https://localhost:%d/%s' % (
              server.port, os.path.split(CERTFILE)[1])
          context = ssl.create_default_context(cafile=SIGNING_CA)
          f = urllib.request.urlopen(url, context=context)
          try:
              dlen = f.info().get("content-length")
              if dlen and (int(dlen) > 0):
                  d2 = f.read(int(dlen))
                  if support.verbose:
                      sys.stdout.write(
                          " client: read %d bytes from remote server '%s'\n"
                          % (len(d2), server))
          finally:
              f.close()
          self.assertEqual(d1, d2)
  
      def test_asyncore_server(self):
          """Check the example asyncore integration."""
          if support.verbose:
              sys.stdout.write("\n")
  
          indata = b"FOO\n"
          server = AsyncoreEchoServer(CERTFILE)
          with server:
              s = test_wrap_socket(socket.socket())
              s.connect(('127.0.0.1', server.port))
              if support.verbose:
                  sys.stdout.write(
                      " client:  sending %r...\n" % indata)
              s.write(indata)
              outdata = s.read()
              if support.verbose:
                  sys.stdout.write(" client:  read %r\n" % outdata)
              if outdata != indata.lower():
                  self.fail(
                      "bad data <<%r>> (%d) received; expected <<%r>> (%d)\n"
                      % (outdata[:20], len(outdata),
                         indata[:20].lower(), len(indata)))
              s.write(b"over\n")
              if support.verbose:
                  sys.stdout.write(" client:  closing connection.\n")
              s.close()
              if support.verbose:
                  sys.stdout.write(" client:  connection closed.\n")
  
      def test_recv_send(self):
          """Test recv(), send() and friends."""
          if support.verbose:
              sys.stdout.write("\n")
  
          server = ThreadedEchoServer(CERTFILE,
                                      certreqs=ssl.CERT_NONE,
                                      ssl_version=ssl.PROTOCOL_TLS_SERVER,
                                      cacerts=CERTFILE,
                                      chatty=True,
                                      connectionchatty=False)
          with server:
              s = test_wrap_socket(socket.socket(),
                                  server_side=False,
                                  certfile=CERTFILE,
                                  ca_certs=CERTFILE,
                                  cert_reqs=ssl.CERT_NONE,
                                  ssl_version=ssl.PROTOCOL_TLS_CLIENT)
              s.connect((HOST, server.port))
              # helper methods for standardising recv* method signatures
              def _recv_into():
                  b = bytearray(b"\0"*100)
                  count = s.recv_into(b)
                  return b[:count]
  
              def _recvfrom_into():
                  b = bytearray(b"\0"*100)
                  count, addr = s.recvfrom_into(b)
                  return b[:count]
  
              # (name, method, expect success?, *args, return value func)
              send_methods = [
                  ('send', s.send, True, [], len),
                  ('sendto', s.sendto, False, ["some.address"], len),
                  ('sendall', s.sendall, True, [], lambda x: None),
              ]
              # (name, method, whether to expect success, *args)
              recv_methods = [
                  ('recv', s.recv, True, []),
                  ('recvfrom', s.recvfrom, False, ["some.address"]),
                  ('recv_into', _recv_into, True, []),
                  ('recvfrom_into', _recvfrom_into, False, []),
              ]
              data_prefix = "PREFIX_"
  
              for (meth_name, send_meth, expect_success, args,
                      ret_val_meth) in send_methods:
                  indata = (data_prefix + meth_name).encode('ascii')
                  try:
                      ret = send_meth(indata, *args)
                      msg = "sending with {}".format(meth_name)
                      self.assertEqual(ret, ret_val_meth(indata), msg=msg)
                      outdata = s.read()
                      if outdata != indata.lower():
                          self.fail(
                              "While sending with <<{name:s}>> bad data "
                              "<<{outdata:r}>> ({nout:d}) received; "
                              "expected <<{indata:r}>> ({nin:d})\n".format(
                                  name=meth_name, outdata=outdata[:20],
                                  nout=len(outdata),
                                  indata=indata[:20], nin=len(indata)
                              )
                          )
                  except ValueError as e:
                      if expect_success:
                          self.fail(
                              "Failed to send with method <<{name:s}>>; "
                              "expected to succeed.\n".format(name=meth_name)
                          )
                      if not str(e).startswith(meth_name):
                          self.fail(
                              "Method <<{name:s}>> failed with unexpected "
                              "exception message: {exp:s}\n".format(
                                  name=meth_name, exp=e
                              )
                          )
  
              for meth_name, recv_meth, expect_success, args in recv_methods:
                  indata = (data_prefix + meth_name).encode('ascii')
                  try:
                      s.send(indata)
                      outdata = recv_meth(*args)
                      if outdata != indata.lower():
                          self.fail(
                              "While receiving with <<{name:s}>> bad data "
                              "<<{outdata:r}>> ({nout:d}) received; "
                              "expected <<{indata:r}>> ({nin:d})\n".format(
                                  name=meth_name, outdata=outdata[:20],
                                  nout=len(outdata),
                                  indata=indata[:20], nin=len(indata)
                              )
                          )
                  except ValueError as e:
                      if expect_success:
                          self.fail(
                              "Failed to receive with method <<{name:s}>>; "
                              "expected to succeed.\n".format(name=meth_name)
                          )
                      if not str(e).startswith(meth_name):
                          self.fail(
                              "Method <<{name:s}>> failed with unexpected "
                              "exception message: {exp:s}\n".format(
                                  name=meth_name, exp=e
                              )
                          )
                      # consume data
                      s.read()
  
              # read(-1, buffer) is supported, even though read(-1) is not
              data = b"data"
              s.send(data)
              buffer = bytearray(len(data))
              self.assertEqual(s.read(-1, buffer), len(data))
              self.assertEqual(buffer, data)
  
              # sendall accepts bytes-like objects
              if ctypes is not None:
                  ubyte = ctypes.c_ubyte * len(data)
                  byteslike = ubyte.from_buffer_copy(data)
                  s.sendall(byteslike)
                  self.assertEqual(s.read(), data)
  
              # Make sure sendmsg et al are disallowed to avoid
              # inadvertent disclosure of data and/or corruption
              # of the encrypted data stream
              self.assertRaises(NotImplementedError, s.dup)
              self.assertRaises(NotImplementedError, s.sendmsg, [b"data"])
              self.assertRaises(NotImplementedError, s.recvmsg, 100)
              self.assertRaises(NotImplementedError,
                                s.recvmsg_into, [bytearray(100)])
              s.write(b"over\n")
  
              self.assertRaises(ValueError, s.recv, -1)
              self.assertRaises(ValueError, s.read, -1)
  
              s.close()
  
      def test_recv_zero(self):
          server = ThreadedEchoServer(CERTFILE)
          server.__enter__()
          self.addCleanup(server.__exit__, None, None)
          s = socket.create_connection((HOST, server.port))
          self.addCleanup(s.close)
          s = test_wrap_socket(s, suppress_ragged_eofs=False)
          self.addCleanup(s.close)
  
          # recv/read(0) should return no data
          s.send(b"data")
          self.assertEqual(s.recv(0), b"")
          self.assertEqual(s.read(0), b"")
          self.assertEqual(s.read(), b"data")
  
          # Should not block if the other end sends no data
          s.setblocking(False)
          self.assertEqual(s.recv(0), b"")
          self.assertEqual(s.recv_into(bytearray()), 0)
  
      def test_nonblocking_send(self):
          server = ThreadedEchoServer(CERTFILE,
                                      certreqs=ssl.CERT_NONE,
                                      ssl_version=ssl.PROTOCOL_TLS_SERVER,
                                      cacerts=CERTFILE,
                                      chatty=True,
                                      connectionchatty=False)
          with server:
              s = test_wrap_socket(socket.socket(),
                                  server_side=False,
                                  certfile=CERTFILE,
                                  ca_certs=CERTFILE,
                                  cert_reqs=ssl.CERT_NONE,
                                  ssl_version=ssl.PROTOCOL_TLS_CLIENT)
              s.connect((HOST, server.port))
              s.setblocking(False)
  
              # If we keep sending data, at some point the buffers
              # will be full and the call will block
              buf = bytearray(8192)
              def fill_buffer():
                  while True:
                      s.send(buf)
              self.assertRaises((ssl.SSLWantWriteError,
                                 ssl.SSLWantReadError), fill_buffer)
  
              # Now read all the output and discard it
              s.setblocking(True)
              s.close()
  
      def test_handshake_timeout(self):
          # Issue #5103: SSL handshake must respect the socket timeout
          server = socket.socket(socket.AF_INET)
          host = "127.0.0.1"
          port = support.bind_port(server)
          started = threading.Event()
          finish = False
  
          def serve():
              server.listen()
              started.set()
              conns = []
              while not finish:
                  r, w, e = select.select([server], [], [], 0.1)
                  if server in r:
                      # Let the socket hang around rather than having
                      # it closed by garbage collection.
                      conns.append(server.accept()[0])
              for sock in conns:
                  sock.close()
  
          t = threading.Thread(target=serve)
          t.start()
          started.wait()
  
          try:
              try:
                  c = socket.socket(socket.AF_INET)
                  c.settimeout(0.2)
                  c.connect((host, port))
                  # Will attempt handshake and time out
                  self.assertRaisesRegex(socket.timeout, "timed out",
                                         test_wrap_socket, c)
              finally:
                  c.close()
              try:
                  c = socket.socket(socket.AF_INET)
                  c = test_wrap_socket(c)
                  c.settimeout(0.2)
                  # Will attempt handshake and time out
                  self.assertRaisesRegex(socket.timeout, "timed out",
                                         c.connect, (host, port))
              finally:
                  c.close()
          finally:
              finish = True
              t.join()
              server.close()
  
      def test_server_accept(self):
          # Issue #16357: accept() on a SSLSocket created through
          # SSLContext.wrap_socket().
          context = ssl.SSLContext(ssl.PROTOCOL_TLS)
          context.verify_mode = ssl.CERT_REQUIRED
          context.load_verify_locations(SIGNING_CA)
          context.load_cert_chain(SIGNED_CERTFILE)
          server = socket.socket(socket.AF_INET)
          host = "127.0.0.1"
          port = support.bind_port(server)
          server = context.wrap_socket(server, server_side=True)
          self.assertTrue(server.server_side)
  
          evt = threading.Event()
          remote = None
          peer = None
          def serve():
              nonlocal remote, peer
              server.listen()
              # Block on the accept and wait on the connection to close.
              evt.set()
              remote, peer = server.accept()
              remote.send(remote.recv(4))
  
          t = threading.Thread(target=serve)
          t.start()
          # Client wait until server setup and perform a connect.
          evt.wait()
          client = context.wrap_socket(socket.socket())
          client.connect((host, port))
          client.send(b'data')
          client.recv()
          client_addr = client.getsockname()
          client.close()
          t.join()
          remote.close()
          server.close()
          # Sanity checks.
          self.assertIsInstance(remote, ssl.SSLSocket)
          self.assertEqual(peer, client_addr)
  
      def test_getpeercert_enotconn(self):
          context = ssl.SSLContext(ssl.PROTOCOL_TLS)
          with context.wrap_socket(socket.socket()) as sock:
              with self.assertRaises(OSError) as cm:
                  sock.getpeercert()
              self.assertEqual(cm.exception.errno, errno.ENOTCONN)
  
      def test_do_handshake_enotconn(self):
          context = ssl.SSLContext(ssl.PROTOCOL_TLS)
          with context.wrap_socket(socket.socket()) as sock:
              with self.assertRaises(OSError) as cm:
                  sock.do_handshake()
              self.assertEqual(cm.exception.errno, errno.ENOTCONN)
  
      def test_no_shared_ciphers(self):
          client_context, server_context, hostname = testing_context()
          # OpenSSL enables all TLS 1.3 ciphers, enforce TLS 1.2 for test
          client_context.options |= ssl.OP_NO_TLSv1_3
          # Force different suites on client and server
          client_context.set_ciphers("AES128")
          server_context.set_ciphers("AES256")
          with ThreadedEchoServer(context=server_context) as server:
              with client_context.wrap_socket(socket.socket(),
                                              server_hostname=hostname) as s:
                  with self.assertRaises(OSError):
                      s.connect((HOST, server.port))
          self.assertIn("no shared cipher", server.conn_errors[0])
  
      def test_version_basic(self):
          """
          Basic tests for SSLSocket.version().
          More tests are done in the test_protocol_*() methods.
          """
          context = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          context.check_hostname = False
          context.verify_mode = ssl.CERT_NONE
          with ThreadedEchoServer(CERTFILE,
                                  ssl_version=ssl.PROTOCOL_TLS_SERVER,
                                  chatty=False) as server:
              with context.wrap_socket(socket.socket()) as s:
                  self.assertIs(s.version(), None)
                  self.assertIs(s._sslobj, None)
                  s.connect((HOST, server.port))
                  if IS_OPENSSL_1_1_1 and ssl.HAS_TLSv1_3:
                      self.assertEqual(s.version(), 'TLSv1.3')
                  elif ssl.OPENSSL_VERSION_INFO >= (1, 0, 2):
                      self.assertEqual(s.version(), 'TLSv1.2')
                  else:  # 0.9.8 to 1.0.1
                      self.assertIn(s.version(), ('TLSv1', 'TLSv1.2'))
              self.assertIs(s._sslobj, None)
              self.assertIs(s.version(), None)
  
      @unittest.skipUnless(ssl.HAS_TLSv1_3,
                           "test requires TLSv1.3 enabled OpenSSL")
      def test_tls1_3(self):
          context = ssl.SSLContext(ssl.PROTOCOL_TLS)
          context.load_cert_chain(CERTFILE)
          context.options |= (
              ssl.OP_NO_TLSv1 | ssl.OP_NO_TLSv1_1 | ssl.OP_NO_TLSv1_2
          )
          with ThreadedEchoServer(context=context) as server:
              with context.wrap_socket(socket.socket()) as s:
                  s.connect((HOST, server.port))
                  self.assertIn(s.cipher()[0], {
                      'TLS_AES_256_GCM_SHA384',
                      'TLS_CHACHA20_POLY1305_SHA256',
                      'TLS_AES_128_GCM_SHA256',
                  })
                  self.assertEqual(s.version(), 'TLSv1.3')
  
      @unittest.skipUnless(hasattr(ssl.SSLContext, 'minimum_version'),
                           "required OpenSSL 1.1.0g")
      def test_min_max_version(self):
          client_context, server_context, hostname = testing_context()
          # client TLSv1.0 to 1.2
          client_context.minimum_version = ssl.TLSVersion.TLSv1
          client_context.maximum_version = ssl.TLSVersion.TLSv1_2
          # server only TLSv1.2
          server_context.minimum_version = ssl.TLSVersion.TLSv1_2
          server_context.maximum_version = ssl.TLSVersion.TLSv1_2
  
          with ThreadedEchoServer(context=server_context) as server:
              with client_context.wrap_socket(socket.socket(),
                                              server_hostname=hostname) as s:
                  s.connect((HOST, server.port))
                  self.assertEqual(s.version(), 'TLSv1.2')
  
          # client 1.0 to 1.2, server 1.0 to 1.1
          server_context.minimum_version = ssl.TLSVersion.TLSv1
          server_context.maximum_version = ssl.TLSVersion.TLSv1_1
  
          with ThreadedEchoServer(context=server_context) as server:
              with client_context.wrap_socket(socket.socket(),
                                              server_hostname=hostname) as s:
                  s.connect((HOST, server.port))
                  self.assertEqual(s.version(), 'TLSv1.1')
  
          # client 1.0, server 1.2 (mismatch)
          server_context.minimum_version = ssl.TLSVersion.TLSv1_2
          server_context.maximum_version = ssl.TLSVersion.TLSv1_2
          client_context.maximum_version = ssl.TLSVersion.TLSv1
          client_context.maximum_version = ssl.TLSVersion.TLSv1
          with ThreadedEchoServer(context=server_context) as server:
              with client_context.wrap_socket(socket.socket(),
                                              server_hostname=hostname) as s:
                  with self.assertRaises(ssl.SSLError) as e:
                      s.connect((HOST, server.port))
                  self.assertIn("alert", str(e.exception))
  
  
      @unittest.skipUnless(hasattr(ssl.SSLContext, 'minimum_version'),
                           "required OpenSSL 1.1.0g")
      @unittest.skipUnless(ssl.HAS_SSLv3, "requires SSLv3 support")
      def test_min_max_version_sslv3(self):
          client_context, server_context, hostname = testing_context()
          server_context.minimum_version = ssl.TLSVersion.SSLv3
          client_context.minimum_version = ssl.TLSVersion.SSLv3
          client_context.maximum_version = ssl.TLSVersion.SSLv3
          with ThreadedEchoServer(context=server_context) as server:
              with client_context.wrap_socket(socket.socket(),
                                              server_hostname=hostname) as s:
                  s.connect((HOST, server.port))
                  self.assertEqual(s.version(), 'SSLv3')
  
      @unittest.skipUnless(ssl.HAS_ECDH, "test requires ECDH-enabled OpenSSL")
      def test_default_ecdh_curve(self):
          # Issue #21015: elliptic curve-based Diffie Hellman key exchange
          # should be enabled by default on SSL contexts.
          context = ssl.SSLContext(ssl.PROTOCOL_TLS)
          context.load_cert_chain(CERTFILE)
          # TLSv1.3 defaults to PFS key agreement and no longer has KEA in
          # cipher name.
          context.options |= ssl.OP_NO_TLSv1_3
          # Prior to OpenSSL 1.0.0, ECDH ciphers have to be enabled
          # explicitly using the 'ECCdraft' cipher alias.  Otherwise,
          # our default cipher list should prefer ECDH-based ciphers
          # automatically.
          if ssl.OPENSSL_VERSION_INFO < (1, 0, 0):
              context.set_ciphers("ECCdraft:ECDH")
          with ThreadedEchoServer(context=context) as server:
              with context.wrap_socket(socket.socket()) as s:
                  s.connect((HOST, server.port))
                  self.assertIn("ECDH", s.cipher()[0])
  
      @unittest.skipUnless("tls-unique" in ssl.CHANNEL_BINDING_TYPES,
                           "'tls-unique' channel binding not available")
      def test_tls_unique_channel_binding(self):
          """Test tls-unique channel binding."""
          if support.verbose:
              sys.stdout.write("\n")
  
          client_context, server_context, hostname = testing_context()
  
          server = ThreadedEchoServer(context=server_context,
                                      chatty=True,
                                      connectionchatty=False)
  
          with server:
              with client_context.wrap_socket(
                      socket.socket(),
                      server_hostname=hostname) as s:
                  s.connect((HOST, server.port))
                  # get the data
                  cb_data = s.get_channel_binding("tls-unique")
                  if support.verbose:
                      sys.stdout.write(
                          " got channel binding data: {0!r}\n".format(cb_data))
  
                  # check if it is sane
                  self.assertIsNotNone(cb_data)
                  if s.version() == 'TLSv1.3':
                      self.assertEqual(len(cb_data), 48)
                  else:
                      self.assertEqual(len(cb_data), 12)  # True for TLSv1
  
                  # and compare with the peers version
                  s.write(b"CB tls-unique\n")
                  peer_data_repr = s.read().strip()
                  self.assertEqual(peer_data_repr,
                                   repr(cb_data).encode("us-ascii"))
  
              # now, again
              with client_context.wrap_socket(
                      socket.socket(),
                      server_hostname=hostname) as s:
                  s.connect((HOST, server.port))
                  new_cb_data = s.get_channel_binding("tls-unique")
                  if support.verbose:
                      sys.stdout.write(
                          "got another channel binding data: {0!r}\n".format(
                              new_cb_data)
                      )
                  # is it really unique
                  self.assertNotEqual(cb_data, new_cb_data)
                  self.assertIsNotNone(cb_data)
                  if s.version() == 'TLSv1.3':
                      self.assertEqual(len(cb_data), 48)
                  else:
                      self.assertEqual(len(cb_data), 12)  # True for TLSv1
                  s.write(b"CB tls-unique\n")
                  peer_data_repr = s.read().strip()
                  self.assertEqual(peer_data_repr,
                                   repr(new_cb_data).encode("us-ascii"))
  
      def test_compression(self):
          client_context, server_context, hostname = testing_context()
          stats = server_params_test(client_context, server_context,
                                     chatty=True, connectionchatty=True,
                                     sni_name=hostname)
          if support.verbose:
              sys.stdout.write(" got compression: {!r}\n".format(stats['compression']))
          self.assertIn(stats['compression'], { None, 'ZLIB', 'RLE' })
  
      @unittest.skipUnless(hasattr(ssl, 'OP_NO_COMPRESSION'),
                           "ssl.OP_NO_COMPRESSION needed for this test")
      def test_compression_disabled(self):
          client_context, server_context, hostname = testing_context()
          client_context.options |= ssl.OP_NO_COMPRESSION
          server_context.options |= ssl.OP_NO_COMPRESSION
          stats = server_params_test(client_context, server_context,
                                     chatty=True, connectionchatty=True,
                                     sni_name=hostname)
          self.assertIs(stats['compression'], None)
  
      @unittest.skipIf(Py_DEBUG_WIN32, "Avoid mixing debug/release CRT on Windows")
      def test_dh_params(self):
          # Check we can get a connection with ephemeral Diffie-Hellman
          client_context, server_context, hostname = testing_context()
          # test scenario needs TLS <= 1.2
          client_context.options |= ssl.OP_NO_TLSv1_3
          server_context.load_dh_params(DHFILE)
          server_context.set_ciphers("kEDH")
          server_context.options |= ssl.OP_NO_TLSv1_3
          stats = server_params_test(client_context, server_context,
                                     chatty=True, connectionchatty=True,
                                     sni_name=hostname)
          cipher = stats["cipher"][0]
          parts = cipher.split("-")
          if "ADH" not in parts and "EDH" not in parts and "DHE" not in parts:
              self.fail("Non-DH cipher: " + cipher[0])
  
      @unittest.skipUnless(HAVE_SECP_CURVES, "needs secp384r1 curve support")
      @unittest.skipIf(IS_OPENSSL_1_1_1, "TODO: Test doesn't work on 1.1.1")
      def test_ecdh_curve(self):
          # server secp384r1, client auto
          client_context, server_context, hostname = testing_context()
  
          server_context.set_ecdh_curve("secp384r1")
          server_context.set_ciphers("ECDHE:!eNULL:!aNULL")
          server_context.options |= ssl.OP_NO_TLSv1 | ssl.OP_NO_TLSv1_1
          stats = server_params_test(client_context, server_context,
                                     chatty=True, connectionchatty=True,
                                     sni_name=hostname)
  
          # server auto, client secp384r1
          client_context, server_context, hostname = testing_context()
          client_context.set_ecdh_curve("secp384r1")
          server_context.set_ciphers("ECDHE:!eNULL:!aNULL")
          server_context.options |= ssl.OP_NO_TLSv1 | ssl.OP_NO_TLSv1_1
          stats = server_params_test(client_context, server_context,
                                     chatty=True, connectionchatty=True,
                                     sni_name=hostname)
  
          # server / client curve mismatch
          client_context, server_context, hostname = testing_context()
          client_context.set_ecdh_curve("prime256v1")
          server_context.set_ecdh_curve("secp384r1")
          server_context.set_ciphers("ECDHE:!eNULL:!aNULL")
          server_context.options |= ssl.OP_NO_TLSv1 | ssl.OP_NO_TLSv1_1
          try:
              stats = server_params_test(client_context, server_context,
                                         chatty=True, connectionchatty=True,
                                         sni_name=hostname)
          except ssl.SSLError:
              pass
          else:
              # OpenSSL 1.0.2 does not fail although it should.
              if IS_OPENSSL_1_1_0:
                  self.fail("mismatch curve did not fail")
  
      def test_selected_alpn_protocol(self):
          # selected_alpn_protocol() is None unless ALPN is used.
          client_context, server_context, hostname = testing_context()
          stats = server_params_test(client_context, server_context,
                                     chatty=True, connectionchatty=True,
                                     sni_name=hostname)
          self.assertIs(stats['client_alpn_protocol'], None)
  
      @unittest.skipUnless(ssl.HAS_ALPN, "ALPN support required")
      def test_selected_alpn_protocol_if_server_uses_alpn(self):
          # selected_alpn_protocol() is None unless ALPN is used by the client.
          client_context, server_context, hostname = testing_context()
          server_context.set_alpn_protocols(['foo', 'bar'])
          stats = server_params_test(client_context, server_context,
                                     chatty=True, connectionchatty=True,
                                     sni_name=hostname)
          self.assertIs(stats['client_alpn_protocol'], None)
  
      @unittest.skipUnless(ssl.HAS_ALPN, "ALPN support needed for this test")
      def test_alpn_protocols(self):
          server_protocols = ['foo', 'bar', 'milkshake']
          protocol_tests = [
              (['foo', 'bar'], 'foo'),
              (['bar', 'foo'], 'foo'),
              (['milkshake'], 'milkshake'),
              (['http/3.0', 'http/4.0'], None)
          ]
          for client_protocols, expected in protocol_tests:
              client_context, server_context, hostname = testing_context()
              server_context.set_alpn_protocols(server_protocols)
              client_context.set_alpn_protocols(client_protocols)
  
              try:
                  stats = server_params_test(client_context,
                                             server_context,
                                             chatty=True,
                                             connectionchatty=True,
                                             sni_name=hostname)
              except ssl.SSLError as e:
                  stats = e
  
              if (expected is None and IS_OPENSSL_1_1_0
                      and ssl.OPENSSL_VERSION_INFO < (1, 1, 0, 6)):
                  # OpenSSL 1.1.0 to 1.1.0e raises handshake error
                  self.assertIsInstance(stats, ssl.SSLError)
              else:
                  msg = "failed trying %s (s) and %s (c).\n" \
                      "was expecting %s, but got %%s from the %%s" \
                          % (str(server_protocols), str(client_protocols),
                              str(expected))
                  client_result = stats['client_alpn_protocol']
                  self.assertEqual(client_result, expected,
                                   msg % (client_result, "client"))
                  server_result = stats['server_alpn_protocols'][-1] \
                      if len(stats['server_alpn_protocols']) else 'nothing'
                  self.assertEqual(server_result, expected,
                                   msg % (server_result, "server"))
  
      def test_selected_npn_protocol(self):
          # selected_npn_protocol() is None unless NPN is used
          client_context, server_context, hostname = testing_context()
          stats = server_params_test(client_context, server_context,
                                     chatty=True, connectionchatty=True,
                                     sni_name=hostname)
          self.assertIs(stats['client_npn_protocol'], None)
  
      @unittest.skipUnless(ssl.HAS_NPN, "NPN support needed for this test")
      def test_npn_protocols(self):
          server_protocols = ['http/1.1', 'spdy/2']
          protocol_tests = [
              (['http/1.1', 'spdy/2'], 'http/1.1'),
              (['spdy/2', 'http/1.1'], 'http/1.1'),
              (['spdy/2', 'test'], 'spdy/2'),
              (['abc', 'def'], 'abc')
          ]
          for client_protocols, expected in protocol_tests:
              client_context, server_context, hostname = testing_context()
              server_context.set_npn_protocols(server_protocols)
              client_context.set_npn_protocols(client_protocols)
              stats = server_params_test(client_context, server_context,
                                         chatty=True, connectionchatty=True,
                                         sni_name=hostname)
              msg = "failed trying %s (s) and %s (c).\n" \
                    "was expecting %s, but got %%s from the %%s" \
                        % (str(server_protocols), str(client_protocols),
                           str(expected))
              client_result = stats['client_npn_protocol']
              self.assertEqual(client_result, expected, msg % (client_result, "client"))
              server_result = stats['server_npn_protocols'][-1] \
                  if len(stats['server_npn_protocols']) else 'nothing'
              self.assertEqual(server_result, expected, msg % (server_result, "server"))
  
      def sni_contexts(self):
          server_context = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
          server_context.load_cert_chain(SIGNED_CERTFILE)
          other_context = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
          other_context.load_cert_chain(SIGNED_CERTFILE2)
          client_context = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          client_context.load_verify_locations(SIGNING_CA)
          return server_context, other_context, client_context
  
      def check_common_name(self, stats, name):
          cert = stats['peercert']
          self.assertIn((('commonName', name),), cert['subject'])
  
      @needs_sni
      def test_sni_callback(self):
          calls = []
          server_context, other_context, client_context = self.sni_contexts()
  
          client_context.check_hostname = False
  
          def servername_cb(ssl_sock, server_name, initial_context):
              calls.append((server_name, initial_context))
              if server_name is not None:
                  ssl_sock.context = other_context
          server_context.set_servername_callback(servername_cb)
  
          stats = server_params_test(client_context, server_context,
                                     chatty=True,
                                     sni_name='supermessage')
          # The hostname was fetched properly, and the certificate was
          # changed for the connection.
          self.assertEqual(calls, [("supermessage", server_context)])
          # CERTFILE4 was selected
          self.check_common_name(stats, 'fakehostname')
  
          calls = []
          # The callback is called with server_name=None
          stats = server_params_test(client_context, server_context,
                                     chatty=True,
                                     sni_name=None)
          self.assertEqual(calls, [(None, server_context)])
          self.check_common_name(stats, SIGNED_CERTFILE_HOSTNAME)
  
          # Check disabling the callback
          calls = []
          server_context.set_servername_callback(None)
  
          stats = server_params_test(client_context, server_context,
                                     chatty=True,
                                     sni_name='notfunny')
          # Certificate didn't change
          self.check_common_name(stats, SIGNED_CERTFILE_HOSTNAME)
          self.assertEqual(calls, [])
  
      @needs_sni
      def test_sni_callback_alert(self):
          # Returning a TLS alert is reflected to the connecting client
          server_context, other_context, client_context = self.sni_contexts()
  
          def cb_returning_alert(ssl_sock, server_name, initial_context):
              return ssl.ALERT_DESCRIPTION_ACCESS_DENIED
          server_context.set_servername_callback(cb_returning_alert)
          with self.assertRaises(ssl.SSLError) as cm:
              stats = server_params_test(client_context, server_context,
                                         chatty=False,
                                         sni_name='supermessage')
          self.assertEqual(cm.exception.reason, 'TLSV1_ALERT_ACCESS_DENIED')
  
      @needs_sni
      def test_sni_callback_raising(self):
          # Raising fails the connection with a TLS handshake failure alert.
          server_context, other_context, client_context = self.sni_contexts()
  
          def cb_raising(ssl_sock, server_name, initial_context):
              1/0
          server_context.set_servername_callback(cb_raising)
  
          with support.catch_unraisable_exception() as catch:
              with self.assertRaises(ssl.SSLError) as cm:
                  stats = server_params_test(client_context, server_context,
                                             chatty=False,
                                             sni_name='supermessage')
  
              self.assertEqual(cm.exception.reason,
                               'SSLV3_ALERT_HANDSHAKE_FAILURE')
              self.assertEqual(catch.unraisable.exc_type, ZeroDivisionError)
  
      @needs_sni
      def test_sni_callback_wrong_return_type(self):
          # Returning the wrong return type terminates the TLS connection
          # with an internal error alert.
          server_context, other_context, client_context = self.sni_contexts()
  
          def cb_wrong_return_type(ssl_sock, server_name, initial_context):
              return "foo"
          server_context.set_servername_callback(cb_wrong_return_type)
  
          with support.catch_unraisable_exception() as catch:
              with self.assertRaises(ssl.SSLError) as cm:
                  stats = server_params_test(client_context, server_context,
                                             chatty=False,
                                             sni_name='supermessage')
  
  
              self.assertEqual(cm.exception.reason, 'TLSV1_ALERT_INTERNAL_ERROR')
              self.assertEqual(catch.unraisable.exc_type, TypeError)
  
      def test_shared_ciphers(self):
          client_context, server_context, hostname = testing_context()
          client_context.set_ciphers("AES128:AES256")
          server_context.set_ciphers("AES256")
          expected_algs = [
              "AES256", "AES-256",
              # TLS 1.3 ciphers are always enabled
              "TLS_CHACHA20", "TLS_AES",
          ]
  
          stats = server_params_test(client_context, server_context,
                                     sni_name=hostname)
          ciphers = stats['server_shared_ciphers'][0]
          self.assertGreater(len(ciphers), 0)
          for name, tls_version, bits in ciphers:
              if not any(alg in name for alg in expected_algs):
                  self.fail(name)
  
      def test_read_write_after_close_raises_valuerror(self):
          client_context, server_context, hostname = testing_context()
          server = ThreadedEchoServer(context=server_context, chatty=False)
  
          with server:
              s = client_context.wrap_socket(socket.socket(),
                                             server_hostname=hostname)
              s.connect((HOST, server.port))
              s.close()
  
              self.assertRaises(ValueError, s.read, 1024)
              self.assertRaises(ValueError, s.write, b'hello')
  
      def test_sendfile(self):
          TEST_DATA = b"x" * 512
          with open(support.TESTFN, 'wb') as f:
              f.write(TEST_DATA)
          self.addCleanup(support.unlink, support.TESTFN)
          context = ssl.SSLContext(ssl.PROTOCOL_TLS)
          context.verify_mode = ssl.CERT_REQUIRED
          context.load_verify_locations(SIGNING_CA)
          context.load_cert_chain(SIGNED_CERTFILE)
          server = ThreadedEchoServer(context=context, chatty=False)
          with server:
              with context.wrap_socket(socket.socket()) as s:
                  s.connect((HOST, server.port))
                  with open(support.TESTFN, 'rb') as file:
                      s.sendfile(file)
                      self.assertEqual(s.recv(1024), TEST_DATA)
  
      def test_session(self):
          client_context, server_context, hostname = testing_context()
          # TODO: sessions aren't compatible with TLSv1.3 yet
          client_context.options |= ssl.OP_NO_TLSv1_3
  
          # first connection without session
          stats = server_params_test(client_context, server_context,
                                     sni_name=hostname)
          session = stats['session']
          self.assertTrue(session.id)
          self.assertGreater(session.time, 0)
          self.assertGreater(session.timeout, 0)
          self.assertTrue(session.has_ticket)
          if ssl.OPENSSL_VERSION_INFO > (1, 0, 1):
              self.assertGreater(session.ticket_lifetime_hint, 0)
          self.assertFalse(stats['session_reused'])
          sess_stat = server_context.session_stats()
          self.assertEqual(sess_stat['accept'], 1)
          self.assertEqual(sess_stat['hits'], 0)
  
          # reuse session
          stats = server_params_test(client_context, server_context,
                                     session=session, sni_name=hostname)
          sess_stat = server_context.session_stats()
          self.assertEqual(sess_stat['accept'], 2)
          self.assertEqual(sess_stat['hits'], 1)
          self.assertTrue(stats['session_reused'])
          session2 = stats['session']
          self.assertEqual(session2.id, session.id)
          self.assertEqual(session2, session)
          self.assertIsNot(session2, session)
          self.assertGreaterEqual(session2.time, session.time)
          self.assertGreaterEqual(session2.timeout, session.timeout)
  
          # another one without session
          stats = server_params_test(client_context, server_context,
                                     sni_name=hostname)
          self.assertFalse(stats['session_reused'])
          session3 = stats['session']
          self.assertNotEqual(session3.id, session.id)
          self.assertNotEqual(session3, session)
          sess_stat = server_context.session_stats()
          self.assertEqual(sess_stat['accept'], 3)
          self.assertEqual(sess_stat['hits'], 1)
  
          # reuse session again
          stats = server_params_test(client_context, server_context,
                                     session=session, sni_name=hostname)
          self.assertTrue(stats['session_reused'])
          session4 = stats['session']
          self.assertEqual(session4.id, session.id)
          self.assertEqual(session4, session)
          self.assertGreaterEqual(session4.time, session.time)
          self.assertGreaterEqual(session4.timeout, session.timeout)
          sess_stat = server_context.session_stats()
          self.assertEqual(sess_stat['accept'], 4)
          self.assertEqual(sess_stat['hits'], 2)
  
      def test_session_handling(self):
          client_context, server_context, hostname = testing_context()
          client_context2, _, _ = testing_context()
  
          # TODO: session reuse does not work with TLSv1.3
          client_context.options |= ssl.OP_NO_TLSv1_3
          client_context2.options |= ssl.OP_NO_TLSv1_3
  
          server = ThreadedEchoServer(context=server_context, chatty=False)
          with server:
              with client_context.wrap_socket(socket.socket(),
                                              server_hostname=hostname) as s:
                  # session is None before handshake
                  self.assertEqual(s.session, None)
                  self.assertEqual(s.session_reused, None)
                  s.connect((HOST, server.port))
                  session = s.session
                  self.assertTrue(session)
                  with self.assertRaises(TypeError) as e:
                      s.session = object
                  self.assertEqual(str(e.exception), 'Value is not a SSLSession.')
  
              with client_context.wrap_socket(socket.socket(),
                                              server_hostname=hostname) as s:
                  s.connect((HOST, server.port))
                  # cannot set session after handshake
                  with self.assertRaises(ValueError) as e:
                      s.session = session
                  self.assertEqual(str(e.exception),
                                   'Cannot set session after handshake.')
  
              with client_context.wrap_socket(socket.socket(),
                                              server_hostname=hostname) as s:
                  # can set session before handshake and before the
                  # connection was established
                  s.session = session
                  s.connect((HOST, server.port))
                  self.assertEqual(s.session.id, session.id)
                  self.assertEqual(s.session, session)
                  self.assertEqual(s.session_reused, True)
  
              with client_context2.wrap_socket(socket.socket(),
                                               server_hostname=hostname) as s:
                  # cannot re-use session with a different SSLContext
                  with self.assertRaises(ValueError) as e:
                      s.session = session
                      s.connect((HOST, server.port))
                  self.assertEqual(str(e.exception),
                                   'Session refers to a different SSLContext.')
  
  
  @unittest.skipUnless(ssl.HAS_TLSv1_3, "Test needs TLS 1.3")
  class TestPostHandshakeAuth(unittest.TestCase):
      def test_pha_setter(self):
          protocols = [
              ssl.PROTOCOL_TLS, ssl.PROTOCOL_TLS_SERVER, ssl.PROTOCOL_TLS_CLIENT
          ]
          for protocol in protocols:
              ctx = ssl.SSLContext(protocol)
              self.assertEqual(ctx.post_handshake_auth, False)
  
              ctx.post_handshake_auth = True
              self.assertEqual(ctx.post_handshake_auth, True)
  
              ctx.verify_mode = ssl.CERT_REQUIRED
              self.assertEqual(ctx.verify_mode, ssl.CERT_REQUIRED)
              self.assertEqual(ctx.post_handshake_auth, True)
  
              ctx.post_handshake_auth = False
              self.assertEqual(ctx.verify_mode, ssl.CERT_REQUIRED)
              self.assertEqual(ctx.post_handshake_auth, False)
  
              ctx.verify_mode = ssl.CERT_OPTIONAL
              ctx.post_handshake_auth = True
              self.assertEqual(ctx.verify_mode, ssl.CERT_OPTIONAL)
              self.assertEqual(ctx.post_handshake_auth, True)
  
      def test_pha_required(self):
          client_context, server_context, hostname = testing_context()
          server_context.post_handshake_auth = True
          server_context.verify_mode = ssl.CERT_REQUIRED
          client_context.post_handshake_auth = True
          client_context.load_cert_chain(SIGNED_CERTFILE)
  
          server = ThreadedEchoServer(context=server_context, chatty=False)
          with server:
              with client_context.wrap_socket(socket.socket(),
                                              server_hostname=hostname) as s:
                  s.connect((HOST, server.port))
                  s.write(b'HASCERT')
                  self.assertEqual(s.recv(1024), b'FALSE\n')
                  s.write(b'PHA')
                  self.assertEqual(s.recv(1024), b'OK\n')
                  s.write(b'HASCERT')
                  self.assertEqual(s.recv(1024), b'TRUE\n')
                  # PHA method just returns true when cert is already available
                  s.write(b'PHA')
                  self.assertEqual(s.recv(1024), b'OK\n')
                  s.write(b'GETCERT')
                  cert_text = s.recv(4096).decode('us-ascii')
                  self.assertIn('Python Software Foundation CA', cert_text)
  
      def test_pha_required_nocert(self):
          client_context, server_context, hostname = testing_context()
          server_context.post_handshake_auth = True
          server_context.verify_mode = ssl.CERT_REQUIRED
          client_context.post_handshake_auth = True
  
          server = ThreadedEchoServer(context=server_context, chatty=False)
          with server:
              with client_context.wrap_socket(socket.socket(),
                                              server_hostname=hostname) as s:
                  s.connect((HOST, server.port))
                  s.write(b'PHA')
                  # receive CertificateRequest
                  self.assertEqual(s.recv(1024), b'OK\n')
                  # send empty Certificate + Finish
                  s.write(b'HASCERT')
                  # receive alert
                  with self.assertRaisesRegex(
                          ssl.SSLError,
                          'tlsv13 alert certificate required'):
                      s.recv(1024)
  
      def test_pha_optional(self):
          if support.verbose:
              sys.stdout.write("\n")
  
          client_context, server_context, hostname = testing_context()
          server_context.post_handshake_auth = True
          server_context.verify_mode = ssl.CERT_REQUIRED
          client_context.post_handshake_auth = True
          client_context.load_cert_chain(SIGNED_CERTFILE)
  
          # check CERT_OPTIONAL
          server_context.verify_mode = ssl.CERT_OPTIONAL
          server = ThreadedEchoServer(context=server_context, chatty=False)
          with server:
              with client_context.wrap_socket(socket.socket(),
                                              server_hostname=hostname) as s:
                  s.connect((HOST, server.port))
                  s.write(b'HASCERT')
                  self.assertEqual(s.recv(1024), b'FALSE\n')
                  s.write(b'PHA')
                  self.assertEqual(s.recv(1024), b'OK\n')
                  s.write(b'HASCERT')
                  self.assertEqual(s.recv(1024), b'TRUE\n')
  
      def test_pha_optional_nocert(self):
          if support.verbose:
              sys.stdout.write("\n")
  
          client_context, server_context, hostname = testing_context()
          server_context.post_handshake_auth = True
          server_context.verify_mode = ssl.CERT_OPTIONAL
          client_context.post_handshake_auth = True
  
          server = ThreadedEchoServer(context=server_context, chatty=False)
          with server:
              with client_context.wrap_socket(socket.socket(),
                                              server_hostname=hostname) as s:
                  s.connect((HOST, server.port))
                  s.write(b'HASCERT')
                  self.assertEqual(s.recv(1024), b'FALSE\n')
                  s.write(b'PHA')
                  self.assertEqual(s.recv(1024), b'OK\n')
                  # optional doesn't fail when client does not have a cert
                  s.write(b'HASCERT')
                  self.assertEqual(s.recv(1024), b'FALSE\n')
  
      def test_pha_no_pha_client(self):
          client_context, server_context, hostname = testing_context()
          server_context.post_handshake_auth = True
          server_context.verify_mode = ssl.CERT_REQUIRED
          client_context.load_cert_chain(SIGNED_CERTFILE)
  
          server = ThreadedEchoServer(context=server_context, chatty=False)
          with server:
              with client_context.wrap_socket(socket.socket(),
                                              server_hostname=hostname) as s:
                  s.connect((HOST, server.port))
                  with self.assertRaisesRegex(ssl.SSLError, 'not server'):
                      s.verify_client_post_handshake()
                  s.write(b'PHA')
                  self.assertIn(b'extension not received', s.recv(1024))
  
      def test_pha_no_pha_server(self):
          # server doesn't have PHA enabled, cert is requested in handshake
          client_context, server_context, hostname = testing_context()
          server_context.verify_mode = ssl.CERT_REQUIRED
          client_context.post_handshake_auth = True
          client_context.load_cert_chain(SIGNED_CERTFILE)
  
          server = ThreadedEchoServer(context=server_context, chatty=False)
          with server:
              with client_context.wrap_socket(socket.socket(),
                                              server_hostname=hostname) as s:
                  s.connect((HOST, server.port))
                  s.write(b'HASCERT')
                  self.assertEqual(s.recv(1024), b'TRUE\n')
                  # PHA doesn't fail if there is already a cert
                  s.write(b'PHA')
                  self.assertEqual(s.recv(1024), b'OK\n')
                  s.write(b'HASCERT')
                  self.assertEqual(s.recv(1024), b'TRUE\n')
  
      def test_pha_not_tls13(self):
          # TLS 1.2
          client_context, server_context, hostname = testing_context()
          server_context.verify_mode = ssl.CERT_REQUIRED
          client_context.maximum_version = ssl.TLSVersion.TLSv1_2
          client_context.post_handshake_auth = True
          client_context.load_cert_chain(SIGNED_CERTFILE)
  
          server = ThreadedEchoServer(context=server_context, chatty=False)
          with server:
              with client_context.wrap_socket(socket.socket(),
                                              server_hostname=hostname) as s:
                  s.connect((HOST, server.port))
                  # PHA fails for TLS != 1.3
                  s.write(b'PHA')
                  self.assertIn(b'WRONG_SSL_VERSION', s.recv(1024))
  
      def test_bpo37428_pha_cert_none(self):
          # verify that post_handshake_auth does not implicitly enable cert
          # validation.
          hostname = SIGNED_CERTFILE_HOSTNAME
          client_context = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          client_context.post_handshake_auth = True
          client_context.load_cert_chain(SIGNED_CERTFILE)
          # no cert validation and CA on client side
          client_context.check_hostname = False
          client_context.verify_mode = ssl.CERT_NONE
  
          server_context = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
          server_context.load_cert_chain(SIGNED_CERTFILE)
          server_context.load_verify_locations(SIGNING_CA)
          server_context.post_handshake_auth = True
          server_context.verify_mode = ssl.CERT_REQUIRED
  
          server = ThreadedEchoServer(context=server_context, chatty=False)
          with server:
              with client_context.wrap_socket(socket.socket(),
                                              server_hostname=hostname) as s:
                  s.connect((HOST, server.port))
                  s.write(b'HASCERT')
                  self.assertEqual(s.recv(1024), b'FALSE\n')
                  s.write(b'PHA')
                  self.assertEqual(s.recv(1024), b'OK\n')
                  s.write(b'HASCERT')
                  self.assertEqual(s.recv(1024), b'TRUE\n')
                  # server cert has not been validated
                  self.assertEqual(s.getpeercert(), {})
  
  
  HAS_KEYLOG = hasattr(ssl.SSLContext, 'keylog_filename')
  requires_keylog = unittest.skipUnless(
      HAS_KEYLOG, 'test requires OpenSSL 1.1.1 with keylog callback')
  
  class TestSSLDebug(unittest.TestCase):
  
      def keylog_lines(self, fname=support.TESTFN):
          with open(fname) as f:
              return len(list(f))
  
      @requires_keylog
      @unittest.skipIf(Py_DEBUG_WIN32, "Avoid mixing debug/release CRT on Windows")
      def test_keylog_defaults(self):
          self.addCleanup(support.unlink, support.TESTFN)
          ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
          self.assertEqual(ctx.keylog_filename, None)
  
          self.assertFalse(os.path.isfile(support.TESTFN))
          ctx.keylog_filename = support.TESTFN
          self.assertEqual(ctx.keylog_filename, support.TESTFN)
          self.assertTrue(os.path.isfile(support.TESTFN))
          self.assertEqual(self.keylog_lines(), 1)
  
          ctx.keylog_filename = None
          self.assertEqual(ctx.keylog_filename, None)
  
          with self.assertRaises((IsADirectoryError, PermissionError)):
              # Windows raises PermissionError
              ctx.keylog_filename = os.path.dirname(
                  os.path.abspath(support.TESTFN))
  
          with self.assertRaises(TypeError):
              ctx.keylog_filename = 1
  
      @requires_keylog
      @unittest.skipIf(Py_DEBUG_WIN32, "Avoid mixing debug/release CRT on Windows")
      def test_keylog_filename(self):
          self.addCleanup(support.unlink, support.TESTFN)
          client_context, server_context, hostname = testing_context()
  
          client_context.keylog_filename = support.TESTFN
          server = ThreadedEchoServer(context=server_context, chatty=False)
          with server:
              with client_context.wrap_socket(socket.socket(),
                                              server_hostname=hostname) as s:
                  s.connect((HOST, server.port))
          # header, 5 lines for TLS 1.3
          self.assertEqual(self.keylog_lines(), 6)
  
          client_context.keylog_filename = None
          server_context.keylog_filename = support.TESTFN
          server = ThreadedEchoServer(context=server_context, chatty=False)
          with server:
              with client_context.wrap_socket(socket.socket(),
                                              server_hostname=hostname) as s:
                  s.connect((HOST, server.port))
          self.assertGreaterEqual(self.keylog_lines(), 11)
  
          client_context.keylog_filename = support.TESTFN
          server_context.keylog_filename = support.TESTFN
          server = ThreadedEchoServer(context=server_context, chatty=False)
          with server:
              with client_context.wrap_socket(socket.socket(),
                                              server_hostname=hostname) as s:
                  s.connect((HOST, server.port))
          self.assertGreaterEqual(self.keylog_lines(), 21)
  
          client_context.keylog_filename = None
          server_context.keylog_filename = None
  
      @requires_keylog
      @unittest.skipIf(sys.flags.ignore_environment,
                       "test is not compatible with ignore_environment")
      @unittest.skipIf(Py_DEBUG_WIN32, "Avoid mixing debug/release CRT on Windows")
      def test_keylog_env(self):
          self.addCleanup(support.unlink, support.TESTFN)
          with unittest.mock.patch.dict(os.environ):
              os.environ['SSLKEYLOGFILE'] = support.TESTFN
              self.assertEqual(os.environ['SSLKEYLOGFILE'], support.TESTFN)
  
              ctx = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
              self.assertEqual(ctx.keylog_filename, None)
  
              ctx = ssl.create_default_context()
              self.assertEqual(ctx.keylog_filename, support.TESTFN)
  
              ctx = ssl._create_stdlib_context()
              self.assertEqual(ctx.keylog_filename, support.TESTFN)
  
      def test_msg_callback(self):
          client_context, server_context, hostname = testing_context()
  
          def msg_cb(conn, direction, version, content_type, msg_type, data):
              pass
  
          self.assertIs(client_context._msg_callback, None)
          client_context._msg_callback = msg_cb
          self.assertIs(client_context._msg_callback, msg_cb)
          with self.assertRaises(TypeError):
              client_context._msg_callback = object()
  
      def test_msg_callback_tls12(self):
          client_context, server_context, hostname = testing_context()
          client_context.options |= ssl.OP_NO_TLSv1_3
  
          msg = []
  
          def msg_cb(conn, direction, version, content_type, msg_type, data):
              self.assertIsInstance(conn, ssl.SSLSocket)
              self.assertIsInstance(data, bytes)
              self.assertIn(direction, {'read', 'write'})
              msg.append((direction, version, content_type, msg_type))
  
          client_context._msg_callback = msg_cb
  
          server = ThreadedEchoServer(context=server_context, chatty=False)
          with server:
              with client_context.wrap_socket(socket.socket(),
                                              server_hostname=hostname) as s:
                  s.connect((HOST, server.port))
  
          self.assertIn(
              ("read", TLSVersion.TLSv1_2, _TLSContentType.HANDSHAKE,
               _TLSMessageType.SERVER_KEY_EXCHANGE),
              msg
          )
          self.assertIn(
              ("write", TLSVersion.TLSv1_2, _TLSContentType.CHANGE_CIPHER_SPEC,
               _TLSMessageType.CHANGE_CIPHER_SPEC),
              msg
          )
  
  
  def test_main(verbose=False):
      if support.verbose:
          plats = {
              'Mac': platform.mac_ver,
              'Windows': platform.win32_ver,
          }
          for name, func in plats.items():
              plat = func()
              if plat and plat[0]:
                  plat = '%s %r' % (name, plat)
                  break
          else:
              plat = repr(platform.platform())
          print("test_ssl: testing with %r %r" %
              (ssl.OPENSSL_VERSION, ssl.OPENSSL_VERSION_INFO))
          print("          under %s" % plat)
          print("          HAS_SNI = %r" % ssl.HAS_SNI)
          print("          OP_ALL = 0x%8x" % ssl.OP_ALL)
          try:
              print("          OP_NO_TLSv1_1 = 0x%8x" % ssl.OP_NO_TLSv1_1)
          except AttributeError:
              pass
  
      for filename in [
          CERTFILE, BYTES_CERTFILE,
          ONLYCERT, ONLYKEY, BYTES_ONLYCERT, BYTES_ONLYKEY,
          SIGNED_CERTFILE, SIGNED_CERTFILE2, SIGNING_CA,
          BADCERT, BADKEY, EMPTYCERT]:
          if not os.path.exists(filename):
              raise support.TestFailed("Can't read certificate file %r" % filename)
  
      tests = [
          ContextTests, BasicSocketTests, SSLErrorTests, MemoryBIOTests,
          SSLObjectTests, SimpleBackgroundTests, ThreadedTests,
          TestPostHandshakeAuth, TestSSLDebug
      ]
  
      if support.is_resource_enabled('network'):
          tests.append(NetworkedTests)
  
      thread_info = support.threading_setup()
      try:
          support.run_unittest(*tests)
      finally:
          support.threading_cleanup(*thread_info)
  
  if __name__ == "__main__":
      test_main()
  