split platform

lib/python3.5/site-packages/cryptography/__about__.py

@@ -0,0 +1,23 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+__all__ = [
+    "__title__", "__summary__", "__uri__", "__version__", "__author__",
+    "__email__", "__license__", "__copyright__",
+]
+
+__title__ = "cryptography"
+__summary__ = ("cryptography is a package which provides cryptographic recipes"
+               " and primitives to Python developers.")
+__uri__ = "https://github.com/pyca/cryptography"
+
+__version__ = "1.1.1"
+
+__author__ = "The cryptography developers"
+__email__ = "cryptography-dev@python.org"
+
+__license__ = "BSD or Apache License, Version 2.0"
+__copyright__ = "Copyright 2013-2015 {0}".format(__author__)

lib/python3.5/site-packages/cryptography/__init__.py

@@ -0,0 +1,26 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import sys
+import warnings
+
+from cryptography.__about__ import (
+    __author__, __copyright__, __email__, __license__, __summary__, __title__,
+    __uri__, __version__
+)
+
+
+__all__ = [
+    "__title__", "__summary__", "__uri__", "__version__", "__author__",
+    "__email__", "__license__", "__copyright__",
+]
+
+if sys.version_info[:2] == (2, 6):
+    warnings.warn(
+        "Python 2.6 is no longer supported by the Python core team, please "
+        "upgrade your Python.",
+        DeprecationWarning
+    )

lib/python3.5/site-packages/cryptography/exceptions.py

@@ -0,0 +1,70 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+from enum import Enum
+
+from cryptography import utils
+from cryptography.hazmat.primitives import twofactor
+
+
+class _Reasons(Enum):
+    BACKEND_MISSING_INTERFACE = 0
+    UNSUPPORTED_HASH = 1
+    UNSUPPORTED_CIPHER = 2
+    UNSUPPORTED_PADDING = 3
+    UNSUPPORTED_MGF = 4
+    UNSUPPORTED_PUBLIC_KEY_ALGORITHM = 5
+    UNSUPPORTED_ELLIPTIC_CURVE = 6
+    UNSUPPORTED_SERIALIZATION = 7
+    UNSUPPORTED_X509 = 8
+    UNSUPPORTED_EXCHANGE_ALGORITHM = 9
+
+
+class UnsupportedAlgorithm(Exception):
+    def __init__(self, message, reason=None):
+        super(UnsupportedAlgorithm, self).__init__(message)
+        self._reason = reason
+
+
+class AlreadyFinalized(Exception):
+    pass
+
+
+class AlreadyUpdated(Exception):
+    pass
+
+
+class NotYetFinalized(Exception):
+    pass
+
+
+class InvalidTag(Exception):
+    pass
+
+
+class InvalidSignature(Exception):
+    pass
+
+
+class InternalError(Exception):
+    def __init__(self, msg, err_code):
+        super(InternalError, self).__init__(msg)
+        self.err_code = err_code
+
+
+class InvalidKey(Exception):
+    pass
+
+
+InvalidToken = utils.deprecated(
+    twofactor.InvalidToken,
+    __name__,
+    (
+        "The InvalidToken exception has moved to the "
+        "cryptography.hazmat.primitives.twofactor module"
+    ),
+    utils.DeprecatedIn09
+)

lib/python3.5/site-packages/cryptography/fernet.py

@@ -0,0 +1,141 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import base64
+import binascii
+import os
+import struct
+import time
+
+import six
+
+from cryptography.exceptions import InvalidSignature
+from cryptography.hazmat.backends import default_backend
+from cryptography.hazmat.primitives import hashes, padding
+from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes
+from cryptography.hazmat.primitives.hmac import HMAC
+
+
+class InvalidToken(Exception):
+    pass
+
+
+_MAX_CLOCK_SKEW = 60
+
+
+class Fernet(object):
+    def __init__(self, key, backend=None):
+        if backend is None:
+            backend = default_backend()
+
+        key = base64.urlsafe_b64decode(key)
+        if len(key) != 32:
+            raise ValueError(
+                "Fernet key must be 32 url-safe base64-encoded bytes."
+            )
+
+        self._signing_key = key[:16]
+        self._encryption_key = key[16:]
+        self._backend = backend
+
+    @classmethod
+    def generate_key(cls):
+        return base64.urlsafe_b64encode(os.urandom(32))
+
+    def encrypt(self, data):
+        current_time = int(time.time())
+        iv = os.urandom(16)
+        return self._encrypt_from_parts(data, current_time, iv)
+
+    def _encrypt_from_parts(self, data, current_time, iv):
+        if not isinstance(data, bytes):
+            raise TypeError("data must be bytes.")
+
+        padder = padding.PKCS7(algorithms.AES.block_size).padder()
+        padded_data = padder.update(data) + padder.finalize()
+        encryptor = Cipher(
+            algorithms.AES(self._encryption_key), modes.CBC(iv), self._backend
+        ).encryptor()
+        ciphertext = encryptor.update(padded_data) + encryptor.finalize()
+
+        basic_parts = (
+            b"\x80" + struct.pack(">Q", current_time) + iv + ciphertext
+        )
+
+        h = HMAC(self._signing_key, hashes.SHA256(), backend=self._backend)
+        h.update(basic_parts)
+        hmac = h.finalize()
+        return base64.urlsafe_b64encode(basic_parts + hmac)
+
+    def decrypt(self, token, ttl=None):
+        if not isinstance(token, bytes):
+            raise TypeError("token must be bytes.")
+
+        current_time = int(time.time())
+
+        try:
+            data = base64.urlsafe_b64decode(token)
+        except (TypeError, binascii.Error):
+            raise InvalidToken
+
+        if not data or six.indexbytes(data, 0) != 0x80:
+            raise InvalidToken
+
+        try:
+            timestamp, = struct.unpack(">Q", data[1:9])
+        except struct.error:
+            raise InvalidToken
+        if ttl is not None:
+            if timestamp + ttl < current_time:
+                raise InvalidToken
+        if current_time + _MAX_CLOCK_SKEW < timestamp:
+            raise InvalidToken
+        h = HMAC(self._signing_key, hashes.SHA256(), backend=self._backend)
+        h.update(data[:-32])
+        try:
+            h.verify(data[-32:])
+        except InvalidSignature:
+            raise InvalidToken
+
+        iv = data[9:25]
+        ciphertext = data[25:-32]
+        decryptor = Cipher(
+            algorithms.AES(self._encryption_key), modes.CBC(iv), self._backend
+        ).decryptor()
+        plaintext_padded = decryptor.update(ciphertext)
+        try:
+            plaintext_padded += decryptor.finalize()
+        except ValueError:
+            raise InvalidToken
+        unpadder = padding.PKCS7(algorithms.AES.block_size).unpadder()
+
+        unpadded = unpadder.update(plaintext_padded)
+        try:
+            unpadded += unpadder.finalize()
+        except ValueError:
+            raise InvalidToken
+        return unpadded
+
+
+class MultiFernet(object):
+    def __init__(self, fernets):
+        fernets = list(fernets)
+        if not fernets:
+            raise ValueError(
+                "MultiFernet requires at least one Fernet instance"
+            )
+        self._fernets = fernets
+
+    def encrypt(self, msg):
+        return self._fernets[0].encrypt(msg)
+
+    def decrypt(self, msg, ttl=None):
+        for f in self._fernets:
+            try:
+                return f.decrypt(msg, ttl)
+            except InvalidToken:
+                pass
+        raise InvalidToken

lib/python3.5/site-packages/cryptography/hazmat/__init__.py

@@ -0,0 +1,5 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function

lib/python3.5/site-packages/cryptography/hazmat/backends/__init__.py

@@ -0,0 +1,42 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import pkg_resources
+
+from cryptography.hazmat.backends.multibackend import MultiBackend
+
+
+_available_backends_list = None
+
+
+def _available_backends():
+    global _available_backends_list
+
+    if _available_backends_list is None:
+        _available_backends_list = [
+            # setuptools 11.3 deprecated support for the require parameter to
+            # load(), and introduced the new resolve() method instead.
+            # This can be removed if/when we can assume setuptools>=11.3. At
+            # some point we may wish to add a warning, to push people along,
+            # but at present this would result in too many warnings.
+            ep.resolve() if hasattr(ep, "resolve") else ep.load(require=False)
+            for ep in pkg_resources.iter_entry_points(
+                "cryptography.backends"
+            )
+        ]
+
+    return _available_backends_list
+
+_default_backend = None
+
+
+def default_backend():
+    global _default_backend
+
+    if _default_backend is None:
+        _default_backend = MultiBackend(_available_backends())
+
+    return _default_backend

lib/python3.5/site-packages/cryptography/hazmat/backends/commoncrypto/__init__.py

@@ -0,0 +1,10 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+from cryptography.hazmat.backends.commoncrypto.backend import backend
+
+
+__all__ = ["backend"]

lib/python3.5/site-packages/cryptography/hazmat/backends/commoncrypto/backend.py

@@ -0,0 +1,245 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+from collections import namedtuple
+
+from cryptography import utils
+from cryptography.exceptions import InternalError
+from cryptography.hazmat.backends.commoncrypto.ciphers import (
+    _CipherContext, _GCMCipherContext
+)
+from cryptography.hazmat.backends.commoncrypto.hashes import _HashContext
+from cryptography.hazmat.backends.commoncrypto.hmac import _HMACContext
+from cryptography.hazmat.backends.interfaces import (
+    CipherBackend, HMACBackend, HashBackend, PBKDF2HMACBackend
+)
+from cryptography.hazmat.bindings.commoncrypto.binding import Binding
+from cryptography.hazmat.primitives.ciphers.algorithms import (
+    AES, ARC4, Blowfish, CAST5, TripleDES
+)
+from cryptography.hazmat.primitives.ciphers.modes import (
+    CBC, CFB, CFB8, CTR, ECB, GCM, OFB
+)
+
+
+HashMethods = namedtuple(
+    "HashMethods", ["ctx", "hash_init", "hash_update", "hash_final"]
+)
+
+
+@utils.register_interface(CipherBackend)
+@utils.register_interface(HashBackend)
+@utils.register_interface(HMACBackend)
+@utils.register_interface(PBKDF2HMACBackend)
+class Backend(object):
+    """
+    CommonCrypto API wrapper.
+    """
+    name = "commoncrypto"
+
+    def __init__(self):
+        self._binding = Binding()
+        self._ffi = self._binding.ffi
+        self._lib = self._binding.lib
+
+        self._cipher_registry = {}
+        self._register_default_ciphers()
+        self._hash_mapping = {
+            "md5": HashMethods(
+                "CC_MD5_CTX *", self._lib.CC_MD5_Init,
+                self._lib.CC_MD5_Update, self._lib.CC_MD5_Final
+            ),
+            "sha1": HashMethods(
+                "CC_SHA1_CTX *", self._lib.CC_SHA1_Init,
+                self._lib.CC_SHA1_Update, self._lib.CC_SHA1_Final
+            ),
+            "sha224": HashMethods(
+                "CC_SHA256_CTX *", self._lib.CC_SHA224_Init,
+                self._lib.CC_SHA224_Update, self._lib.CC_SHA224_Final
+            ),
+            "sha256": HashMethods(
+                "CC_SHA256_CTX *", self._lib.CC_SHA256_Init,
+                self._lib.CC_SHA256_Update, self._lib.CC_SHA256_Final
+            ),
+            "sha384": HashMethods(
+                "CC_SHA512_CTX *", self._lib.CC_SHA384_Init,
+                self._lib.CC_SHA384_Update, self._lib.CC_SHA384_Final
+            ),
+            "sha512": HashMethods(
+                "CC_SHA512_CTX *", self._lib.CC_SHA512_Init,
+                self._lib.CC_SHA512_Update, self._lib.CC_SHA512_Final
+            ),
+        }
+
+        self._supported_hmac_algorithms = {
+            "md5": self._lib.kCCHmacAlgMD5,
+            "sha1": self._lib.kCCHmacAlgSHA1,
+            "sha224": self._lib.kCCHmacAlgSHA224,
+            "sha256": self._lib.kCCHmacAlgSHA256,
+            "sha384": self._lib.kCCHmacAlgSHA384,
+            "sha512": self._lib.kCCHmacAlgSHA512,
+        }
+
+        self._supported_pbkdf2_hmac_algorithms = {
+            "sha1": self._lib.kCCPRFHmacAlgSHA1,
+            "sha224": self._lib.kCCPRFHmacAlgSHA224,
+            "sha256": self._lib.kCCPRFHmacAlgSHA256,
+            "sha384": self._lib.kCCPRFHmacAlgSHA384,
+            "sha512": self._lib.kCCPRFHmacAlgSHA512,
+        }
+
+    def hash_supported(self, algorithm):
+        return algorithm.name in self._hash_mapping
+
+    def hmac_supported(self, algorithm):
+        return algorithm.name in self._supported_hmac_algorithms
+
+    def create_hash_ctx(self, algorithm):
+        return _HashContext(self, algorithm)
+
+    def create_hmac_ctx(self, key, algorithm):
+        return _HMACContext(self, key, algorithm)
+
+    def cipher_supported(self, cipher, mode):
+        return (type(cipher), type(mode)) in self._cipher_registry
+
+    def create_symmetric_encryption_ctx(self, cipher, mode):
+        if isinstance(mode, GCM):
+            return _GCMCipherContext(
+                self, cipher, mode, self._lib.kCCEncrypt
+            )
+        else:
+            return _CipherContext(self, cipher, mode, self._lib.kCCEncrypt)
+
+    def create_symmetric_decryption_ctx(self, cipher, mode):
+        if isinstance(mode, GCM):
+            return _GCMCipherContext(
+                self, cipher, mode, self._lib.kCCDecrypt
+            )
+        else:
+            return _CipherContext(self, cipher, mode, self._lib.kCCDecrypt)
+
+    def pbkdf2_hmac_supported(self, algorithm):
+        return algorithm.name in self._supported_pbkdf2_hmac_algorithms
+
+    def derive_pbkdf2_hmac(self, algorithm, length, salt, iterations,
+                           key_material):
+        alg_enum = self._supported_pbkdf2_hmac_algorithms[algorithm.name]
+        buf = self._ffi.new("char[]", length)
+        res = self._lib.CCKeyDerivationPBKDF(
+            self._lib.kCCPBKDF2,
+            key_material,
+            len(key_material),
+            salt,
+            len(salt),
+            alg_enum,
+            iterations,
+            buf,
+            length
+        )
+        self._check_cipher_response(res)
+
+        return self._ffi.buffer(buf)[:]
+
+    def _register_cipher_adapter(self, cipher_cls, cipher_const, mode_cls,
+                                 mode_const):
+        if (cipher_cls, mode_cls) in self._cipher_registry:
+            raise ValueError("Duplicate registration for: {0} {1}.".format(
+                cipher_cls, mode_cls)
+            )
+        self._cipher_registry[cipher_cls, mode_cls] = (cipher_const,
+                                                       mode_const)
+
+    def _register_default_ciphers(self):
+        for mode_cls, mode_const in [
+            (CBC, self._lib.kCCModeCBC),
+            (ECB, self._lib.kCCModeECB),
+            (CFB, self._lib.kCCModeCFB),
+            (CFB8, self._lib.kCCModeCFB8),
+            (OFB, self._lib.kCCModeOFB),
+            (CTR, self._lib.kCCModeCTR),
+            (GCM, self._lib.kCCModeGCM),
+        ]:
+            self._register_cipher_adapter(
+                AES,
+                self._lib.kCCAlgorithmAES128,
+                mode_cls,
+                mode_const
+            )
+        for mode_cls, mode_const in [
+            (CBC, self._lib.kCCModeCBC),
+            (ECB, self._lib.kCCModeECB),
+            (CFB, self._lib.kCCModeCFB),
+            (CFB8, self._lib.kCCModeCFB8),
+            (OFB, self._lib.kCCModeOFB),
+        ]:
+            self._register_cipher_adapter(
+                TripleDES,
+                self._lib.kCCAlgorithm3DES,
+                mode_cls,
+                mode_const
+            )
+        for mode_cls, mode_const in [
+            (CBC, self._lib.kCCModeCBC),
+            (ECB, self._lib.kCCModeECB),
+            (CFB, self._lib.kCCModeCFB),
+            (OFB, self._lib.kCCModeOFB)
+        ]:
+            self._register_cipher_adapter(
+                Blowfish,
+                self._lib.kCCAlgorithmBlowfish,
+                mode_cls,
+                mode_const
+            )
+        for mode_cls, mode_const in [
+            (CBC, self._lib.kCCModeCBC),
+            (ECB, self._lib.kCCModeECB),
+            (CFB, self._lib.kCCModeCFB),
+            (OFB, self._lib.kCCModeOFB),
+            (CTR, self._lib.kCCModeCTR)
+        ]:
+            self._register_cipher_adapter(
+                CAST5,
+                self._lib.kCCAlgorithmCAST,
+                mode_cls,
+                mode_const
+            )
+        self._register_cipher_adapter(
+            ARC4,
+            self._lib.kCCAlgorithmRC4,
+            type(None),
+            self._lib.kCCModeRC4
+        )
+
+    def _check_cipher_response(self, response):
+        if response == self._lib.kCCSuccess:
+            return
+        elif response == self._lib.kCCAlignmentError:
+            # This error is not currently triggered due to a bug filed as
+            # rdar://15589470
+            raise ValueError(
+                "The length of the provided data is not a multiple of "
+                "the block length."
+            )
+        else:
+            raise InternalError(
+                "The backend returned an unknown error, consider filing a bug."
+                " Code: {0}.".format(response),
+                response
+            )
+
+    def _release_cipher_ctx(self, ctx):
+        """
+        Called by the garbage collector and used to safely dereference and
+        release the context.
+        """
+        if ctx[0] != self._ffi.NULL:
+            res = self._lib.CCCryptorRelease(ctx[0])
+            self._check_cipher_response(res)
+            ctx[0] = self._ffi.NULL
+
+
+backend = Backend()

lib/python3.5/site-packages/cryptography/hazmat/backends/commoncrypto/ciphers.py

@@ -0,0 +1,193 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+from cryptography import utils
+from cryptography.exceptions import (
+    InvalidTag, UnsupportedAlgorithm, _Reasons
+)
+from cryptography.hazmat.primitives import ciphers, constant_time
+from cryptography.hazmat.primitives.ciphers import modes
+from cryptography.hazmat.primitives.ciphers.modes import (
+    CFB, CFB8, CTR, OFB
+)
+
+
+@utils.register_interface(ciphers.CipherContext)
+class _CipherContext(object):
+    def __init__(self, backend, cipher, mode, operation):
+        self._backend = backend
+        self._cipher = cipher
+        self._mode = mode
+        self._operation = operation
+        # There is a bug in CommonCrypto where block ciphers do not raise
+        # kCCAlignmentError when finalizing if you supply non-block aligned
+        # data. To work around this we need to keep track of the block
+        # alignment ourselves, but only for alg+mode combos that require
+        # block alignment. OFB, CFB, and CTR make a block cipher algorithm
+        # into a stream cipher so we don't need to track them (and thus their
+        # block size is effectively 1 byte just like OpenSSL/CommonCrypto
+        # treat RC4 and other stream cipher block sizes).
+        # This bug has been filed as rdar://15589470
+        self._bytes_processed = 0
+        if (isinstance(cipher, ciphers.BlockCipherAlgorithm) and not
+                isinstance(mode, (OFB, CFB, CFB8, CTR))):
+            self._byte_block_size = cipher.block_size // 8
+        else:
+            self._byte_block_size = 1
+
+        registry = self._backend._cipher_registry
+        try:
+            cipher_enum, mode_enum = registry[type(cipher), type(mode)]
+        except KeyError:
+            raise UnsupportedAlgorithm(
+                "cipher {0} in {1} mode is not supported "
+                "by this backend.".format(
+                    cipher.name, mode.name if mode else mode),
+                _Reasons.UNSUPPORTED_CIPHER
+            )
+
+        ctx = self._backend._ffi.new("CCCryptorRef *")
+        ctx = self._backend._ffi.gc(ctx, self._backend._release_cipher_ctx)
+
+        if isinstance(mode, modes.ModeWithInitializationVector):
+            iv_nonce = mode.initialization_vector
+        elif isinstance(mode, modes.ModeWithNonce):
+            iv_nonce = mode.nonce
+        else:
+            iv_nonce = self._backend._ffi.NULL
+
+        if isinstance(mode, CTR):
+            mode_option = self._backend._lib.kCCModeOptionCTR_BE
+        else:
+            mode_option = 0
+
+        res = self._backend._lib.CCCryptorCreateWithMode(
+            operation,
+            mode_enum, cipher_enum,
+            self._backend._lib.ccNoPadding, iv_nonce,
+            cipher.key, len(cipher.key),
+            self._backend._ffi.NULL, 0, 0, mode_option, ctx)
+        self._backend._check_cipher_response(res)
+
+        self._ctx = ctx
+
+    def update(self, data):
+        # Count bytes processed to handle block alignment.
+        self._bytes_processed += len(data)
+        buf = self._backend._ffi.new(
+            "unsigned char[]", len(data) + self._byte_block_size - 1)
+        outlen = self._backend._ffi.new("size_t *")
+        res = self._backend._lib.CCCryptorUpdate(
+            self._ctx[0], data, len(data), buf,
+            len(data) + self._byte_block_size - 1, outlen)
+        self._backend._check_cipher_response(res)
+        return self._backend._ffi.buffer(buf)[:outlen[0]]
+
+    def finalize(self):
+        # Raise error if block alignment is wrong.
+        if self._bytes_processed % self._byte_block_size:
+            raise ValueError(
+                "The length of the provided data is not a multiple of "
+                "the block length."
+            )
+        buf = self._backend._ffi.new("unsigned char[]", self._byte_block_size)
+        outlen = self._backend._ffi.new("size_t *")
+        res = self._backend._lib.CCCryptorFinal(
+            self._ctx[0], buf, len(buf), outlen)
+        self._backend._check_cipher_response(res)
+        self._backend._release_cipher_ctx(self._ctx)
+        return self._backend._ffi.buffer(buf)[:outlen[0]]
+
+
+@utils.register_interface(ciphers.AEADCipherContext)
+@utils.register_interface(ciphers.AEADEncryptionContext)
+class _GCMCipherContext(object):
+    def __init__(self, backend, cipher, mode, operation):
+        self._backend = backend
+        self._cipher = cipher
+        self._mode = mode
+        self._operation = operation
+        self._tag = None
+
+        registry = self._backend._cipher_registry
+        try:
+            cipher_enum, mode_enum = registry[type(cipher), type(mode)]
+        except KeyError:
+            raise UnsupportedAlgorithm(
+                "cipher {0} in {1} mode is not supported "
+                "by this backend.".format(
+                    cipher.name, mode.name if mode else mode),
+                _Reasons.UNSUPPORTED_CIPHER
+            )
+
+        ctx = self._backend._ffi.new("CCCryptorRef *")
+        ctx = self._backend._ffi.gc(ctx, self._backend._release_cipher_ctx)
+
+        self._ctx = ctx
+
+        res = self._backend._lib.CCCryptorCreateWithMode(
+            operation,
+            mode_enum, cipher_enum,
+            self._backend._lib.ccNoPadding,
+            self._backend._ffi.NULL,
+            cipher.key, len(cipher.key),
+            self._backend._ffi.NULL, 0, 0, 0, self._ctx)
+        self._backend._check_cipher_response(res)
+
+        res = self._backend._lib.CCCryptorGCMAddIV(
+            self._ctx[0],
+            mode.initialization_vector,
+            len(mode.initialization_vector)
+        )
+        self._backend._check_cipher_response(res)
+        # CommonCrypto has a bug where calling update without at least one
+        # call to authenticate_additional_data will result in null byte output
+        # for ciphertext. The following empty byte string call prevents the
+        # issue, which is present in at least 10.8 and 10.9.
+        # Filed as rdar://18314544
+        self.authenticate_additional_data(b"")
+
+    def update(self, data):
+        buf = self._backend._ffi.new("unsigned char[]", len(data))
+        args = (self._ctx[0], data, len(data), buf)
+        if self._operation == self._backend._lib.kCCEncrypt:
+            res = self._backend._lib.CCCryptorGCMEncrypt(*args)
+        else:
+            res = self._backend._lib.CCCryptorGCMDecrypt(*args)
+
+        self._backend._check_cipher_response(res)
+        return self._backend._ffi.buffer(buf)[:]
+
+    def finalize(self):
+        # CommonCrypto has a yet another bug where you must make at least one
+        # call to update. If you pass just AAD and call finalize without a call
+        # to update you'll get null bytes for tag. The following update call
+        # prevents this issue, which is present in at least 10.8 and 10.9.
+        # Filed as rdar://18314580
+        self.update(b"")
+        tag_size = self._cipher.block_size // 8
+        tag_buf = self._backend._ffi.new("unsigned char[]", tag_size)
+        tag_len = self._backend._ffi.new("size_t *", tag_size)
+        res = self._backend._lib.CCCryptorGCMFinal(
+            self._ctx[0], tag_buf, tag_len
+        )
+        self._backend._check_cipher_response(res)
+        self._backend._release_cipher_ctx(self._ctx)
+        self._tag = self._backend._ffi.buffer(tag_buf)[:]
+        if (self._operation == self._backend._lib.kCCDecrypt and
+                not constant_time.bytes_eq(
+                    self._tag[:len(self._mode.tag)], self._mode.tag
+                )):
+            raise InvalidTag
+        return b""
+
+    def authenticate_additional_data(self, data):
+        res = self._backend._lib.CCCryptorGCMAddAAD(
+            self._ctx[0], data, len(data)
+        )
+        self._backend._check_cipher_response(res)
+
+    tag = utils.read_only_property("_tag")

lib/python3.5/site-packages/cryptography/hazmat/backends/commoncrypto/hashes.py

@@ -0,0 +1,55 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+from cryptography import utils
+from cryptography.exceptions import UnsupportedAlgorithm, _Reasons
+from cryptography.hazmat.primitives import hashes
+
+
+@utils.register_interface(hashes.HashContext)
+class _HashContext(object):
+    def __init__(self, backend, algorithm, ctx=None):
+        self._algorithm = algorithm
+        self._backend = backend
+
+        if ctx is None:
+            try:
+                methods = self._backend._hash_mapping[self.algorithm.name]
+            except KeyError:
+                raise UnsupportedAlgorithm(
+                    "{0} is not a supported hash on this backend.".format(
+                        algorithm.name),
+                    _Reasons.UNSUPPORTED_HASH
+                )
+            ctx = self._backend._ffi.new(methods.ctx)
+            res = methods.hash_init(ctx)
+            assert res == 1
+
+        self._ctx = ctx
+
+    algorithm = utils.read_only_property("_algorithm")
+
+    def copy(self):
+        methods = self._backend._hash_mapping[self.algorithm.name]
+        new_ctx = self._backend._ffi.new(methods.ctx)
+        # CommonCrypto has no APIs for copying hashes, so we have to copy the
+        # underlying struct.
+        new_ctx[0] = self._ctx[0]
+
+        return _HashContext(self._backend, self.algorithm, ctx=new_ctx)
+
+    def update(self, data):
+        methods = self._backend._hash_mapping[self.algorithm.name]
+        res = methods.hash_update(self._ctx, data, len(data))
+        assert res == 1
+
+    def finalize(self):
+        methods = self._backend._hash_mapping[self.algorithm.name]
+        buf = self._backend._ffi.new("unsigned char[]",
+                                     self.algorithm.digest_size)
+        res = methods.hash_final(buf, self._ctx)
+        assert res == 1
+        return self._backend._ffi.buffer(buf)[:]

lib/python3.5/site-packages/cryptography/hazmat/backends/commoncrypto/hmac.py

@@ -0,0 +1,59 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+from cryptography import utils
+from cryptography.exceptions import (
+    InvalidSignature, UnsupportedAlgorithm, _Reasons
+)
+from cryptography.hazmat.primitives import constant_time, hashes, interfaces
+
+
+@utils.register_interface(interfaces.MACContext)
+@utils.register_interface(hashes.HashContext)
+class _HMACContext(object):
+    def __init__(self, backend, key, algorithm, ctx=None):
+        self._algorithm = algorithm
+        self._backend = backend
+        if ctx is None:
+            ctx = self._backend._ffi.new("CCHmacContext *")
+            try:
+                alg = self._backend._supported_hmac_algorithms[algorithm.name]
+            except KeyError:
+                raise UnsupportedAlgorithm(
+                    "{0} is not a supported HMAC hash on this backend.".format(
+                        algorithm.name),
+                    _Reasons.UNSUPPORTED_HASH
+                )
+
+            self._backend._lib.CCHmacInit(ctx, alg, key, len(key))
+
+        self._ctx = ctx
+        self._key = key
+
+    algorithm = utils.read_only_property("_algorithm")
+
+    def copy(self):
+        copied_ctx = self._backend._ffi.new("CCHmacContext *")
+        # CommonCrypto has no APIs for copying HMACs, so we have to copy the
+        # underlying struct.
+        copied_ctx[0] = self._ctx[0]
+        return _HMACContext(
+            self._backend, self._key, self.algorithm, ctx=copied_ctx
+        )
+
+    def update(self, data):
+        self._backend._lib.CCHmacUpdate(self._ctx, data, len(data))
+
+    def finalize(self):
+        buf = self._backend._ffi.new("unsigned char[]",
+                                     self.algorithm.digest_size)
+        self._backend._lib.CCHmacFinal(self._ctx, buf)
+        return self._backend._ffi.buffer(buf)[:]
+
+    def verify(self, signature):
+        digest = self.finalize()
+        if not constant_time.bytes_eq(digest, signature):
+            raise InvalidSignature("Signature did not match digest.")

lib/python3.5/site-packages/cryptography/hazmat/backends/interfaces.py

@@ -0,0 +1,345 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import abc
+
+import six
+
+
+@six.add_metaclass(abc.ABCMeta)
+class CipherBackend(object):
+    @abc.abstractmethod
+    def cipher_supported(self, cipher, mode):
+        """
+        Return True if the given cipher and mode are supported.
+        """
+
+    @abc.abstractmethod
+    def create_symmetric_encryption_ctx(self, cipher, mode):
+        """
+        Get a CipherContext that can be used for encryption.
+        """
+
+    @abc.abstractmethod
+    def create_symmetric_decryption_ctx(self, cipher, mode):
+        """
+        Get a CipherContext that can be used for decryption.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class HashBackend(object):
+    @abc.abstractmethod
+    def hash_supported(self, algorithm):
+        """
+        Return True if the hash algorithm is supported by this backend.
+        """
+
+    @abc.abstractmethod
+    def create_hash_ctx(self, algorithm):
+        """
+        Create a HashContext for calculating a message digest.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class HMACBackend(object):
+    @abc.abstractmethod
+    def hmac_supported(self, algorithm):
+        """
+        Return True if the hash algorithm is supported for HMAC by this
+        backend.
+        """
+
+    @abc.abstractmethod
+    def create_hmac_ctx(self, key, algorithm):
+        """
+        Create a MACContext for calculating a message authentication code.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class CMACBackend(object):
+    @abc.abstractmethod
+    def cmac_algorithm_supported(self, algorithm):
+        """
+        Returns True if the block cipher is supported for CMAC by this backend
+        """
+
+    @abc.abstractmethod
+    def create_cmac_ctx(self, algorithm):
+        """
+        Create a MACContext for calculating a message authentication code.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class PBKDF2HMACBackend(object):
+    @abc.abstractmethod
+    def pbkdf2_hmac_supported(self, algorithm):
+        """
+        Return True if the hash algorithm is supported for PBKDF2 by this
+        backend.
+        """
+
+    @abc.abstractmethod
+    def derive_pbkdf2_hmac(self, algorithm, length, salt, iterations,
+                           key_material):
+        """
+        Return length bytes derived from provided PBKDF2 parameters.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class RSABackend(object):
+    @abc.abstractmethod
+    def generate_rsa_private_key(self, public_exponent, key_size):
+        """
+        Generate an RSAPrivateKey instance with public_exponent and a modulus
+        of key_size bits.
+        """
+
+    @abc.abstractmethod
+    def rsa_padding_supported(self, padding):
+        """
+        Returns True if the backend supports the given padding options.
+        """
+
+    @abc.abstractmethod
+    def generate_rsa_parameters_supported(self, public_exponent, key_size):
+        """
+        Returns True if the backend supports the given parameters for key
+        generation.
+        """
+
+    @abc.abstractmethod
+    def load_rsa_private_numbers(self, numbers):
+        """
+        Returns an RSAPrivateKey provider.
+        """
+
+    @abc.abstractmethod
+    def load_rsa_public_numbers(self, numbers):
+        """
+        Returns an RSAPublicKey provider.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class DSABackend(object):
+    @abc.abstractmethod
+    def generate_dsa_parameters(self, key_size):
+        """
+        Generate a DSAParameters instance with a modulus of key_size bits.
+        """
+
+    @abc.abstractmethod
+    def generate_dsa_private_key(self, parameters):
+        """
+        Generate a DSAPrivateKey instance with parameters as a DSAParameters
+        object.
+        """
+
+    @abc.abstractmethod
+    def generate_dsa_private_key_and_parameters(self, key_size):
+        """
+        Generate a DSAPrivateKey instance using key size only.
+        """
+
+    @abc.abstractmethod
+    def dsa_hash_supported(self, algorithm):
+        """
+        Return True if the hash algorithm is supported by the backend for DSA.
+        """
+
+    @abc.abstractmethod
+    def dsa_parameters_supported(self, p, q, g):
+        """
+        Return True if the parameters are supported by the backend for DSA.
+        """
+
+    @abc.abstractmethod
+    def load_dsa_private_numbers(self, numbers):
+        """
+        Returns a DSAPrivateKey provider.
+        """
+
+    @abc.abstractmethod
+    def load_dsa_public_numbers(self, numbers):
+        """
+        Returns a DSAPublicKey provider.
+        """
+
+    @abc.abstractmethod
+    def load_dsa_parameter_numbers(self, numbers):
+        """
+        Returns a DSAParameters provider.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class EllipticCurveBackend(object):
+    @abc.abstractmethod
+    def elliptic_curve_signature_algorithm_supported(
+        self, signature_algorithm, curve
+    ):
+        """
+        Returns True if the backend supports the named elliptic curve with the
+        specified signature algorithm.
+        """
+
+    @abc.abstractmethod
+    def elliptic_curve_supported(self, curve):
+        """
+        Returns True if the backend supports the named elliptic curve.
+        """
+
+    @abc.abstractmethod
+    def generate_elliptic_curve_private_key(self, curve):
+        """
+        Return an object conforming to the EllipticCurvePrivateKey interface.
+        """
+
+    @abc.abstractmethod
+    def load_elliptic_curve_public_numbers(self, numbers):
+        """
+        Return an EllipticCurvePublicKey provider using the given numbers.
+        """
+
+    @abc.abstractmethod
+    def load_elliptic_curve_private_numbers(self, numbers):
+        """
+        Return an EllipticCurvePrivateKey provider using the given numbers.
+        """
+
+    @abc.abstractmethod
+    def elliptic_curve_exchange_algorithm_supported(self, algorithm, curve):
+        """
+        Returns whether the exchange algorithm is supported by this backend.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class PEMSerializationBackend(object):
+    @abc.abstractmethod
+    def load_pem_private_key(self, data, password):
+        """
+        Loads a private key from PEM encoded data, using the provided password
+        if the data is encrypted.
+        """
+
+    @abc.abstractmethod
+    def load_pem_public_key(self, data):
+        """
+        Loads a public key from PEM encoded data.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class DERSerializationBackend(object):
+    @abc.abstractmethod
+    def load_der_private_key(self, data, password):
+        """
+        Loads a private key from DER encoded data. Uses the provided password
+        if the data is encrypted.
+        """
+
+    @abc.abstractmethod
+    def load_der_public_key(self, data):
+        """
+        Loads a public key from DER encoded data.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class X509Backend(object):
+    @abc.abstractmethod
+    def load_pem_x509_certificate(self, data):
+        """
+        Load an X.509 certificate from PEM encoded data.
+        """
+
+    @abc.abstractmethod
+    def load_der_x509_certificate(self, data):
+        """
+        Load an X.509 certificate from DER encoded data.
+        """
+
+    @abc.abstractmethod
+    def load_der_x509_csr(self, data):
+        """
+        Load an X.509 CSR from DER encoded data.
+        """
+
+    @abc.abstractmethod
+    def load_pem_x509_csr(self, data):
+        """
+        Load an X.509 CSR from PEM encoded data.
+        """
+
+    @abc.abstractmethod
+    def create_x509_csr(self, builder, private_key, algorithm):
+        """
+        Create and sign an X.509 CSR from a CSR builder object.
+        """
+
+    @abc.abstractmethod
+    def create_x509_certificate(self, builder, private_key, algorithm):
+        """
+        Create and sign an X.509 certificate from a CertificateBuilder object.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class DHBackend(object):
+    @abc.abstractmethod
+    def generate_dh_parameters(self, key_size):
+        """
+        Generate a DHParameters instance with a modulus of key_size bits.
+        """
+
+    @abc.abstractmethod
+    def generate_dh_private_key(self, parameters):
+        """
+        Generate a DHPrivateKey instance with parameters as a DHParameters
+        object.
+        """
+
+    @abc.abstractmethod
+    def generate_dh_private_key_and_parameters(self, key_size):
+        """
+        Generate a DHPrivateKey instance using key size only.
+        """
+
+    @abc.abstractmethod
+    def load_dh_private_numbers(self, numbers):
+        """
+        Returns a DHPrivateKey provider.
+        """
+
+    @abc.abstractmethod
+    def load_dh_public_numbers(self, numbers):
+        """
+        Returns a DHPublicKey provider.
+        """
+
+    @abc.abstractmethod
+    def load_dh_parameter_numbers(self, numbers):
+        """
+        Returns a DHParameters provider.
+        """
+
+    @abc.abstractmethod
+    def dh_exchange_algorithm_supported(self, exchange_algorithm):
+        """
+        Returns whether the exchange algorithm is supported by this backend.
+        """
+
+    @abc.abstractmethod
+    def dh_parameters_supported(self, p, g):
+        """
+        Returns whether the backend supports DH with these parameter values.
+        """

lib/python3.5/site-packages/cryptography/hazmat/backends/multibackend.py

@@ -0,0 +1,386 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+from cryptography import utils
+from cryptography.exceptions import UnsupportedAlgorithm, _Reasons
+from cryptography.hazmat.backends.interfaces import (
+    CMACBackend, CipherBackend, DERSerializationBackend, DSABackend,
+    EllipticCurveBackend, HMACBackend, HashBackend, PBKDF2HMACBackend,
+    PEMSerializationBackend, RSABackend, X509Backend
+)
+
+
+@utils.register_interface(CMACBackend)
+@utils.register_interface(CipherBackend)
+@utils.register_interface(DERSerializationBackend)
+@utils.register_interface(HashBackend)
+@utils.register_interface(HMACBackend)
+@utils.register_interface(PBKDF2HMACBackend)
+@utils.register_interface(RSABackend)
+@utils.register_interface(DSABackend)
+@utils.register_interface(EllipticCurveBackend)
+@utils.register_interface(PEMSerializationBackend)
+@utils.register_interface(X509Backend)
+class MultiBackend(object):
+    name = "multibackend"
+
+    def __init__(self, backends):
+        self._backends = backends
+
+    def _filtered_backends(self, interface):
+        for b in self._backends:
+            if isinstance(b, interface):
+                yield b
+
+    def cipher_supported(self, cipher, mode):
+        return any(
+            b.cipher_supported(cipher, mode)
+            for b in self._filtered_backends(CipherBackend)
+        )
+
+    def create_symmetric_encryption_ctx(self, cipher, mode):
+        for b in self._filtered_backends(CipherBackend):
+            try:
+                return b.create_symmetric_encryption_ctx(cipher, mode)
+            except UnsupportedAlgorithm:
+                pass
+        raise UnsupportedAlgorithm(
+            "cipher {0} in {1} mode is not supported by this backend.".format(
+                cipher.name, mode.name if mode else mode),
+            _Reasons.UNSUPPORTED_CIPHER
+        )
+
+    def create_symmetric_decryption_ctx(self, cipher, mode):
+        for b in self._filtered_backends(CipherBackend):
+            try:
+                return b.create_symmetric_decryption_ctx(cipher, mode)
+            except UnsupportedAlgorithm:
+                pass
+        raise UnsupportedAlgorithm(
+            "cipher {0} in {1} mode is not supported by this backend.".format(
+                cipher.name, mode.name if mode else mode),
+            _Reasons.UNSUPPORTED_CIPHER
+        )
+
+    def hash_supported(self, algorithm):
+        return any(
+            b.hash_supported(algorithm)
+            for b in self._filtered_backends(HashBackend)
+        )
+
+    def create_hash_ctx(self, algorithm):
+        for b in self._filtered_backends(HashBackend):
+            try:
+                return b.create_hash_ctx(algorithm)
+            except UnsupportedAlgorithm:
+                pass
+        raise UnsupportedAlgorithm(
+            "{0} is not a supported hash on this backend.".format(
+                algorithm.name),
+            _Reasons.UNSUPPORTED_HASH
+        )
+
+    def hmac_supported(self, algorithm):
+        return any(
+            b.hmac_supported(algorithm)
+            for b in self._filtered_backends(HMACBackend)
+        )
+
+    def create_hmac_ctx(self, key, algorithm):
+        for b in self._filtered_backends(HMACBackend):
+            try:
+                return b.create_hmac_ctx(key, algorithm)
+            except UnsupportedAlgorithm:
+                pass
+        raise UnsupportedAlgorithm(
+            "{0} is not a supported hash on this backend.".format(
+                algorithm.name),
+            _Reasons.UNSUPPORTED_HASH
+        )
+
+    def pbkdf2_hmac_supported(self, algorithm):
+        return any(
+            b.pbkdf2_hmac_supported(algorithm)
+            for b in self._filtered_backends(PBKDF2HMACBackend)
+        )
+
+    def derive_pbkdf2_hmac(self, algorithm, length, salt, iterations,
+                           key_material):
+        for b in self._filtered_backends(PBKDF2HMACBackend):
+            try:
+                return b.derive_pbkdf2_hmac(
+                    algorithm, length, salt, iterations, key_material
+                )
+            except UnsupportedAlgorithm:
+                pass
+        raise UnsupportedAlgorithm(
+            "{0} is not a supported hash on this backend.".format(
+                algorithm.name),
+            _Reasons.UNSUPPORTED_HASH
+        )
+
+    def generate_rsa_private_key(self, public_exponent, key_size):
+        for b in self._filtered_backends(RSABackend):
+            return b.generate_rsa_private_key(public_exponent, key_size)
+        raise UnsupportedAlgorithm("RSA is not supported by the backend.",
+                                   _Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM)
+
+    def generate_rsa_parameters_supported(self, public_exponent, key_size):
+        for b in self._filtered_backends(RSABackend):
+            return b.generate_rsa_parameters_supported(
+                public_exponent, key_size
+            )
+        raise UnsupportedAlgorithm("RSA is not supported by the backend.",
+                                   _Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM)
+
+    def rsa_padding_supported(self, padding):
+        for b in self._filtered_backends(RSABackend):
+            return b.rsa_padding_supported(padding)
+        raise UnsupportedAlgorithm("RSA is not supported by the backend.",
+                                   _Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM)
+
+    def load_rsa_private_numbers(self, numbers):
+        for b in self._filtered_backends(RSABackend):
+            return b.load_rsa_private_numbers(numbers)
+
+        raise UnsupportedAlgorithm("RSA is not supported by the backend",
+                                   _Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM)
+
+    def load_rsa_public_numbers(self, numbers):
+        for b in self._filtered_backends(RSABackend):
+            return b.load_rsa_public_numbers(numbers)
+
+        raise UnsupportedAlgorithm("RSA is not supported by the backend",
+                                   _Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM)
+
+    def generate_dsa_parameters(self, key_size):
+        for b in self._filtered_backends(DSABackend):
+            return b.generate_dsa_parameters(key_size)
+        raise UnsupportedAlgorithm("DSA is not supported by the backend.",
+                                   _Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM)
+
+    def generate_dsa_private_key(self, parameters):
+        for b in self._filtered_backends(DSABackend):
+            return b.generate_dsa_private_key(parameters)
+        raise UnsupportedAlgorithm("DSA is not supported by the backend.",
+                                   _Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM)
+
+    def generate_dsa_private_key_and_parameters(self, key_size):
+        for b in self._filtered_backends(DSABackend):
+            return b.generate_dsa_private_key_and_parameters(key_size)
+        raise UnsupportedAlgorithm("DSA is not supported by the backend.",
+                                   _Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM)
+
+    def dsa_hash_supported(self, algorithm):
+        for b in self._filtered_backends(DSABackend):
+            return b.dsa_hash_supported(algorithm)
+        raise UnsupportedAlgorithm("DSA is not supported by the backend.",
+                                   _Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM)
+
+    def dsa_parameters_supported(self, p, q, g):
+        for b in self._filtered_backends(DSABackend):
+            return b.dsa_parameters_supported(p, q, g)
+        raise UnsupportedAlgorithm("DSA is not supported by the backend.",
+                                   _Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM)
+
+    def load_dsa_public_numbers(self, numbers):
+        for b in self._filtered_backends(DSABackend):
+            return b.load_dsa_public_numbers(numbers)
+        raise UnsupportedAlgorithm("DSA is not supported by the backend.",
+                                   _Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM)
+
+    def load_dsa_private_numbers(self, numbers):
+        for b in self._filtered_backends(DSABackend):
+            return b.load_dsa_private_numbers(numbers)
+        raise UnsupportedAlgorithm("DSA is not supported by the backend.",
+                                   _Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM)
+
+    def load_dsa_parameter_numbers(self, numbers):
+        for b in self._filtered_backends(DSABackend):
+            return b.load_dsa_parameter_numbers(numbers)
+        raise UnsupportedAlgorithm("DSA is not supported by the backend.",
+                                   _Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM)
+
+    def cmac_algorithm_supported(self, algorithm):
+        return any(
+            b.cmac_algorithm_supported(algorithm)
+            for b in self._filtered_backends(CMACBackend)
+        )
+
+    def create_cmac_ctx(self, algorithm):
+        for b in self._filtered_backends(CMACBackend):
+            try:
+                return b.create_cmac_ctx(algorithm)
+            except UnsupportedAlgorithm:
+                pass
+        raise UnsupportedAlgorithm("This backend does not support CMAC.",
+                                   _Reasons.UNSUPPORTED_CIPHER)
+
+    def elliptic_curve_supported(self, curve):
+        return any(
+            b.elliptic_curve_supported(curve)
+            for b in self._filtered_backends(EllipticCurveBackend)
+        )
+
+    def elliptic_curve_signature_algorithm_supported(
+        self, signature_algorithm, curve
+    ):
+        return any(
+            b.elliptic_curve_signature_algorithm_supported(
+                signature_algorithm, curve
+            )
+            for b in self._filtered_backends(EllipticCurveBackend)
+        )
+
+    def generate_elliptic_curve_private_key(self, curve):
+        for b in self._filtered_backends(EllipticCurveBackend):
+            try:
+                return b.generate_elliptic_curve_private_key(curve)
+            except UnsupportedAlgorithm:
+                continue
+
+        raise UnsupportedAlgorithm(
+            "This backend does not support this elliptic curve.",
+            _Reasons.UNSUPPORTED_ELLIPTIC_CURVE
+        )
+
+    def load_elliptic_curve_private_numbers(self, numbers):
+        for b in self._filtered_backends(EllipticCurveBackend):
+            try:
+                return b.load_elliptic_curve_private_numbers(numbers)
+            except UnsupportedAlgorithm:
+                continue
+
+        raise UnsupportedAlgorithm(
+            "This backend does not support this elliptic curve.",
+            _Reasons.UNSUPPORTED_ELLIPTIC_CURVE
+        )
+
+    def load_elliptic_curve_public_numbers(self, numbers):
+        for b in self._filtered_backends(EllipticCurveBackend):
+            try:
+                return b.load_elliptic_curve_public_numbers(numbers)
+            except UnsupportedAlgorithm:
+                continue
+
+        raise UnsupportedAlgorithm(
+            "This backend does not support this elliptic curve.",
+            _Reasons.UNSUPPORTED_ELLIPTIC_CURVE
+        )
+
+    def elliptic_curve_exchange_algorithm_supported(self, algorithm, curve):
+        return any(
+            b.elliptic_curve_exchange_algorithm_supported(algorithm, curve)
+            for b in self._filtered_backends(EllipticCurveBackend)
+        )
+
+    def load_pem_private_key(self, data, password):
+        for b in self._filtered_backends(PEMSerializationBackend):
+            return b.load_pem_private_key(data, password)
+
+        raise UnsupportedAlgorithm(
+            "This backend does not support this key serialization.",
+            _Reasons.UNSUPPORTED_SERIALIZATION
+        )
+
+    def load_pem_public_key(self, data):
+        for b in self._filtered_backends(PEMSerializationBackend):
+            return b.load_pem_public_key(data)
+
+        raise UnsupportedAlgorithm(
+            "This backend does not support this key serialization.",
+            _Reasons.UNSUPPORTED_SERIALIZATION
+        )
+
+    def load_der_private_key(self, data, password):
+        for b in self._filtered_backends(DERSerializationBackend):
+            return b.load_der_private_key(data, password)
+
+        raise UnsupportedAlgorithm(
+            "This backend does not support this key serialization.",
+            _Reasons.UNSUPPORTED_SERIALIZATION
+        )
+
+    def load_der_public_key(self, data):
+        for b in self._filtered_backends(DERSerializationBackend):
+            return b.load_der_public_key(data)
+
+        raise UnsupportedAlgorithm(
+            "This backend does not support this key serialization.",
+            _Reasons.UNSUPPORTED_SERIALIZATION
+        )
+
+    def load_pem_x509_certificate(self, data):
+        for b in self._filtered_backends(X509Backend):
+            return b.load_pem_x509_certificate(data)
+
+        raise UnsupportedAlgorithm(
+            "This backend does not support X.509.",
+            _Reasons.UNSUPPORTED_X509
+        )
+
+    def load_der_x509_certificate(self, data):
+        for b in self._filtered_backends(X509Backend):
+            return b.load_der_x509_certificate(data)
+
+        raise UnsupportedAlgorithm(
+            "This backend does not support X.509.",
+            _Reasons.UNSUPPORTED_X509
+        )
+
+    def load_pem_x509_crl(self, data):
+        for b in self._filtered_backends(X509Backend):
+            return b.load_pem_x509_crl(data)
+
+        raise UnsupportedAlgorithm(
+            "This backend does not support X.509.",
+            _Reasons.UNSUPPORTED_X509
+        )
+
+    def load_der_x509_crl(self, data):
+        for b in self._filtered_backends(X509Backend):
+            return b.load_der_x509_crl(data)
+
+        raise UnsupportedAlgorithm(
+            "This backend does not support X.509.",
+            _Reasons.UNSUPPORTED_X509
+        )
+
+    def load_der_x509_csr(self, data):
+        for b in self._filtered_backends(X509Backend):
+            return b.load_der_x509_csr(data)
+
+        raise UnsupportedAlgorithm(
+            "This backend does not support X.509.",
+            _Reasons.UNSUPPORTED_X509
+        )
+
+    def load_pem_x509_csr(self, data):
+        for b in self._filtered_backends(X509Backend):
+            return b.load_pem_x509_csr(data)
+
+        raise UnsupportedAlgorithm(
+            "This backend does not support X.509.",
+            _Reasons.UNSUPPORTED_X509
+        )
+
+    def create_x509_csr(self, builder, private_key, algorithm):
+        for b in self._filtered_backends(X509Backend):
+            return b.create_x509_csr(builder, private_key, algorithm)
+
+        raise UnsupportedAlgorithm(
+            "This backend does not support X.509.",
+            _Reasons.UNSUPPORTED_X509
+        )
+
+    def create_x509_certificate(self, builder, private_key, algorithm):
+        for b in self._filtered_backends(X509Backend):
+            return b.create_x509_certificate(builder, private_key, algorithm)
+
+        raise UnsupportedAlgorithm(
+            "This backend does not support X.509.",
+            _Reasons.UNSUPPORTED_X509
+        )

lib/python3.5/site-packages/cryptography/hazmat/backends/openssl/__init__.py

@@ -0,0 +1,10 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+from cryptography.hazmat.backends.openssl.backend import backend
+
+
+__all__ = ["backend"]

lib/python3.5/site-packages/cryptography/hazmat/backends/openssl/ciphers.py

@@ -0,0 +1,213 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+from cryptography import utils
+from cryptography.exceptions import InvalidTag, UnsupportedAlgorithm, _Reasons
+from cryptography.hazmat.primitives import ciphers
+from cryptography.hazmat.primitives.ciphers import modes
+
+
+@utils.register_interface(ciphers.CipherContext)
+@utils.register_interface(ciphers.AEADCipherContext)
+@utils.register_interface(ciphers.AEADEncryptionContext)
+class _CipherContext(object):
+    _ENCRYPT = 1
+    _DECRYPT = 0
+
+    def __init__(self, backend, cipher, mode, operation):
+        self._backend = backend
+        self._cipher = cipher
+        self._mode = mode
+        self._operation = operation
+        self._tag = None
+
+        if isinstance(self._cipher, ciphers.BlockCipherAlgorithm):
+            self._block_size = self._cipher.block_size
+        else:
+            self._block_size = 1
+
+        ctx = self._backend._lib.EVP_CIPHER_CTX_new()
+        ctx = self._backend._ffi.gc(
+            ctx, self._backend._lib.EVP_CIPHER_CTX_free
+        )
+
+        registry = self._backend._cipher_registry
+        try:
+            adapter = registry[type(cipher), type(mode)]
+        except KeyError:
+            raise UnsupportedAlgorithm(
+                "cipher {0} in {1} mode is not supported "
+                "by this backend.".format(
+                    cipher.name, mode.name if mode else mode),
+                _Reasons.UNSUPPORTED_CIPHER
+            )
+
+        evp_cipher = adapter(self._backend, cipher, mode)
+        if evp_cipher == self._backend._ffi.NULL:
+            raise UnsupportedAlgorithm(
+                "cipher {0} in {1} mode is not supported "
+                "by this backend.".format(
+                    cipher.name, mode.name if mode else mode),
+                _Reasons.UNSUPPORTED_CIPHER
+            )
+
+        if isinstance(mode, modes.ModeWithInitializationVector):
+            iv_nonce = mode.initialization_vector
+        elif isinstance(mode, modes.ModeWithNonce):
+            iv_nonce = mode.nonce
+        else:
+            iv_nonce = self._backend._ffi.NULL
+        # begin init with cipher and operation type
+        res = self._backend._lib.EVP_CipherInit_ex(ctx, evp_cipher,
+                                                   self._backend._ffi.NULL,
+                                                   self._backend._ffi.NULL,
+                                                   self._backend._ffi.NULL,
+                                                   operation)
+        self._backend.openssl_assert(res != 0)
+        # set the key length to handle variable key ciphers
+        res = self._backend._lib.EVP_CIPHER_CTX_set_key_length(
+            ctx, len(cipher.key)
+        )
+        self._backend.openssl_assert(res != 0)
+        if isinstance(mode, modes.GCM):
+            res = self._backend._lib.EVP_CIPHER_CTX_ctrl(
+                ctx, self._backend._lib.EVP_CTRL_GCM_SET_IVLEN,
+                len(iv_nonce), self._backend._ffi.NULL
+            )
+            self._backend.openssl_assert(res != 0)
+            if operation == self._DECRYPT:
+                res = self._backend._lib.EVP_CIPHER_CTX_ctrl(
+                    ctx, self._backend._lib.EVP_CTRL_GCM_SET_TAG,
+                    len(mode.tag), mode.tag
+                )
+                self._backend.openssl_assert(res != 0)
+
+        # pass key/iv
+        res = self._backend._lib.EVP_CipherInit_ex(
+            ctx,
+            self._backend._ffi.NULL,
+            self._backend._ffi.NULL,
+            cipher.key,
+            iv_nonce,
+            operation
+        )
+        self._backend.openssl_assert(res != 0)
+        # We purposely disable padding here as it's handled higher up in the
+        # API.
+        self._backend._lib.EVP_CIPHER_CTX_set_padding(ctx, 0)
+        self._ctx = ctx
+
+    def update(self, data):
+        # OpenSSL 0.9.8e has an assertion in its EVP code that causes it
+        # to SIGABRT if you call update with an empty byte string. This can be
+        # removed when we drop support for 0.9.8e (CentOS/RHEL 5). This branch
+        # should be taken only when length is zero and mode is not GCM because
+        # AES GCM can return improper tag values if you don't call update
+        # with empty plaintext when authenticating AAD for ...reasons.
+        if len(data) == 0 and not isinstance(self._mode, modes.GCM):
+            return b""
+
+        buf = self._backend._ffi.new("unsigned char[]",
+                                     len(data) + self._block_size - 1)
+        outlen = self._backend._ffi.new("int *")
+        res = self._backend._lib.EVP_CipherUpdate(self._ctx, buf, outlen, data,
+                                                  len(data))
+        self._backend.openssl_assert(res != 0)
+        return self._backend._ffi.buffer(buf)[:outlen[0]]
+
+    def finalize(self):
+        # OpenSSL 1.0.1 on Ubuntu 12.04 (and possibly other distributions)
+        # appears to have a bug where you must make at least one call to update
+        # even if you are only using authenticate_additional_data or the
+        # GCM tag will be wrong. An (empty) call to update resolves this
+        # and is harmless for all other versions of OpenSSL.
+        if isinstance(self._mode, modes.GCM):
+            self.update(b"")
+
+        buf = self._backend._ffi.new("unsigned char[]", self._block_size)
+        outlen = self._backend._ffi.new("int *")
+        res = self._backend._lib.EVP_CipherFinal_ex(self._ctx, buf, outlen)
+        if res == 0:
+            errors = self._backend._consume_errors()
+
+            if not errors and isinstance(self._mode, modes.GCM):
+                raise InvalidTag
+
+            self._backend.openssl_assert(
+                errors[0][1:] == (
+                    self._backend._lib.ERR_LIB_EVP,
+                    self._backend._lib.EVP_F_EVP_ENCRYPTFINAL_EX,
+                    self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
+                ) or errors[0][1:] == (
+                    self._backend._lib.ERR_LIB_EVP,
+                    self._backend._lib.EVP_F_EVP_DECRYPTFINAL_EX,
+                    self._backend._lib.EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH
+                )
+            )
+            raise ValueError(
+                "The length of the provided data is not a multiple of "
+                "the block length."
+            )
+
+        if (isinstance(self._mode, modes.GCM) and
+           self._operation == self._ENCRYPT):
+            block_byte_size = self._block_size // 8
+            tag_buf = self._backend._ffi.new(
+                "unsigned char[]", block_byte_size
+            )
+            res = self._backend._lib.EVP_CIPHER_CTX_ctrl(
+                self._ctx, self._backend._lib.EVP_CTRL_GCM_GET_TAG,
+                block_byte_size, tag_buf
+            )
+            self._backend.openssl_assert(res != 0)
+            self._tag = self._backend._ffi.buffer(tag_buf)[:]
+
+        res = self._backend._lib.EVP_CIPHER_CTX_cleanup(self._ctx)
+        self._backend.openssl_assert(res == 1)
+        return self._backend._ffi.buffer(buf)[:outlen[0]]
+
+    def authenticate_additional_data(self, data):
+        outlen = self._backend._ffi.new("int *")
+        res = self._backend._lib.EVP_CipherUpdate(
+            self._ctx, self._backend._ffi.NULL, outlen, data, len(data)
+        )
+        self._backend.openssl_assert(res != 0)
+
+    tag = utils.read_only_property("_tag")
+
+
+@utils.register_interface(ciphers.CipherContext)
+class _AESCTRCipherContext(object):
+    """
+    This is needed to provide support for AES CTR mode in OpenSSL 0.9.8. It can
+    be removed when we drop 0.9.8 support (RHEL5 extended life ends 2020).
+    """
+    def __init__(self, backend, cipher, mode):
+        self._backend = backend
+
+        self._key = self._backend._ffi.new("AES_KEY *")
+        res = self._backend._lib.AES_set_encrypt_key(
+            cipher.key, len(cipher.key) * 8, self._key
+        )
+        self._backend.openssl_assert(res == 0)
+        self._ecount = self._backend._ffi.new("char[]", 16)
+        self._nonce = self._backend._ffi.new("char[16]", mode.nonce)
+        self._num = self._backend._ffi.new("unsigned int *", 0)
+
+    def update(self, data):
+        buf = self._backend._ffi.new("unsigned char[]", len(data))
+        self._backend._lib.AES_ctr128_encrypt(
+            data, buf, len(data), self._key, self._nonce,
+            self._ecount, self._num
+        )
+        return self._backend._ffi.buffer(buf)[:]
+
+    def finalize(self):
+        self._key = None
+        self._ecount = None
+        self._nonce = None
+        self._num = None
+        return b""

lib/python3.5/site-packages/cryptography/hazmat/backends/openssl/cmac.py

@@ -0,0 +1,80 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+
+from cryptography import utils
+from cryptography.exceptions import (
+    InvalidSignature, UnsupportedAlgorithm, _Reasons
+)
+from cryptography.hazmat.primitives import constant_time, interfaces
+from cryptography.hazmat.primitives.ciphers.modes import CBC
+
+
+@utils.register_interface(interfaces.MACContext)
+class _CMACContext(object):
+    def __init__(self, backend, algorithm, ctx=None):
+        if not backend.cmac_algorithm_supported(algorithm):
+            raise UnsupportedAlgorithm("This backend does not support CMAC.",
+                                       _Reasons.UNSUPPORTED_CIPHER)
+
+        self._backend = backend
+        self._key = algorithm.key
+        self._algorithm = algorithm
+        self._output_length = algorithm.block_size // 8
+
+        if ctx is None:
+            registry = self._backend._cipher_registry
+            adapter = registry[type(algorithm), CBC]
+
+            evp_cipher = adapter(self._backend, algorithm, CBC)
+
+            ctx = self._backend._lib.CMAC_CTX_new()
+
+            self._backend.openssl_assert(ctx != self._backend._ffi.NULL)
+            ctx = self._backend._ffi.gc(ctx, self._backend._lib.CMAC_CTX_free)
+
+            self._backend._lib.CMAC_Init(
+                ctx, self._key, len(self._key),
+                evp_cipher, self._backend._ffi.NULL
+            )
+
+        self._ctx = ctx
+
+    algorithm = utils.read_only_property("_algorithm")
+
+    def update(self, data):
+        res = self._backend._lib.CMAC_Update(self._ctx, data, len(data))
+        self._backend.openssl_assert(res == 1)
+
+    def finalize(self):
+        buf = self._backend._ffi.new("unsigned char[]", self._output_length)
+        length = self._backend._ffi.new("size_t *", self._output_length)
+        res = self._backend._lib.CMAC_Final(
+            self._ctx, buf, length
+        )
+        self._backend.openssl_assert(res == 1)
+
+        self._ctx = None
+
+        return self._backend._ffi.buffer(buf)[:]
+
+    def copy(self):
+        copied_ctx = self._backend._lib.CMAC_CTX_new()
+        copied_ctx = self._backend._ffi.gc(
+            copied_ctx, self._backend._lib.CMAC_CTX_free
+        )
+        res = self._backend._lib.CMAC_CTX_copy(
+            copied_ctx, self._ctx
+        )
+        self._backend.openssl_assert(res == 1)
+        return _CMACContext(
+            self._backend, self._algorithm, ctx=copied_ctx
+        )
+
+    def verify(self, signature):
+        digest = self.finalize()
+        if not constant_time.bytes_eq(digest, signature):
+            raise InvalidSignature("Signature did not match digest.")

lib/python3.5/site-packages/cryptography/hazmat/backends/openssl/dsa.py

@@ -0,0 +1,218 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+from cryptography import utils
+from cryptography.exceptions import InvalidSignature
+from cryptography.hazmat.backends.openssl.utils import _truncate_digest
+from cryptography.hazmat.primitives import hashes, serialization
+from cryptography.hazmat.primitives.asymmetric import (
+    AsymmetricSignatureContext, AsymmetricVerificationContext, dsa
+)
+
+
+def _truncate_digest_for_dsa(dsa_cdata, digest, backend):
+    """
+    This function truncates digests that are longer than a given DS
+    key's length so they can be signed. OpenSSL does this for us in
+    1.0.0c+ and it isn't needed in 0.9.8, but that leaves us with three
+    releases (1.0.0, 1.0.0a, and 1.0.0b) where this is a problem. This
+    truncation is not required in 0.9.8 because DSA is limited to SHA-1.
+    """
+
+    order_bits = backend._lib.BN_num_bits(dsa_cdata.q)
+    return _truncate_digest(digest, order_bits)
+
+
+@utils.register_interface(AsymmetricVerificationContext)
+class _DSAVerificationContext(object):
+    def __init__(self, backend, public_key, signature, algorithm):
+        self._backend = backend
+        self._public_key = public_key
+        self._signature = signature
+        self._algorithm = algorithm
+
+        self._hash_ctx = hashes.Hash(self._algorithm, self._backend)
+
+    def update(self, data):
+        self._hash_ctx.update(data)
+
+    def verify(self):
+        data_to_verify = self._hash_ctx.finalize()
+
+        data_to_verify = _truncate_digest_for_dsa(
+            self._public_key._dsa_cdata, data_to_verify, self._backend
+        )
+
+        # The first parameter passed to DSA_verify is unused by OpenSSL but
+        # must be an integer.
+        res = self._backend._lib.DSA_verify(
+            0, data_to_verify, len(data_to_verify), self._signature,
+            len(self._signature), self._public_key._dsa_cdata)
+
+        if res != 1:
+            self._backend._consume_errors()
+            raise InvalidSignature
+
+
+@utils.register_interface(AsymmetricSignatureContext)
+class _DSASignatureContext(object):
+    def __init__(self, backend, private_key, algorithm):
+        self._backend = backend
+        self._private_key = private_key
+        self._algorithm = algorithm
+        self._hash_ctx = hashes.Hash(self._algorithm, self._backend)
+
+    def update(self, data):
+        self._hash_ctx.update(data)
+
+    def finalize(self):
+        data_to_sign = self._hash_ctx.finalize()
+        data_to_sign = _truncate_digest_for_dsa(
+            self._private_key._dsa_cdata, data_to_sign, self._backend
+        )
+        sig_buf_len = self._backend._lib.DSA_size(self._private_key._dsa_cdata)
+        sig_buf = self._backend._ffi.new("unsigned char[]", sig_buf_len)
+        buflen = self._backend._ffi.new("unsigned int *")
+
+        # The first parameter passed to DSA_sign is unused by OpenSSL but
+        # must be an integer.
+        res = self._backend._lib.DSA_sign(
+            0, data_to_sign, len(data_to_sign), sig_buf,
+            buflen, self._private_key._dsa_cdata)
+        self._backend.openssl_assert(res == 1)
+        self._backend.openssl_assert(buflen[0])
+
+        return self._backend._ffi.buffer(sig_buf)[:buflen[0]]
+
+
+@utils.register_interface(dsa.DSAParametersWithNumbers)
+class _DSAParameters(object):
+    def __init__(self, backend, dsa_cdata):
+        self._backend = backend
+        self._dsa_cdata = dsa_cdata
+
+    def parameter_numbers(self):
+        return dsa.DSAParameterNumbers(
+            p=self._backend._bn_to_int(self._dsa_cdata.p),
+            q=self._backend._bn_to_int(self._dsa_cdata.q),
+            g=self._backend._bn_to_int(self._dsa_cdata.g)
+        )
+
+    def generate_private_key(self):
+        return self._backend.generate_dsa_private_key(self)
+
+
+@utils.register_interface(dsa.DSAPrivateKeyWithSerialization)
+class _DSAPrivateKey(object):
+    def __init__(self, backend, dsa_cdata, evp_pkey):
+        self._backend = backend
+        self._dsa_cdata = dsa_cdata
+        self._evp_pkey = evp_pkey
+        self._key_size = self._backend._lib.BN_num_bits(self._dsa_cdata.p)
+
+    key_size = utils.read_only_property("_key_size")
+
+    def signer(self, signature_algorithm):
+        return _DSASignatureContext(self._backend, self, signature_algorithm)
+
+    def private_numbers(self):
+        return dsa.DSAPrivateNumbers(
+            public_numbers=dsa.DSAPublicNumbers(
+                parameter_numbers=dsa.DSAParameterNumbers(
+                    p=self._backend._bn_to_int(self._dsa_cdata.p),
+                    q=self._backend._bn_to_int(self._dsa_cdata.q),
+                    g=self._backend._bn_to_int(self._dsa_cdata.g)
+                ),
+                y=self._backend._bn_to_int(self._dsa_cdata.pub_key)
+            ),
+            x=self._backend._bn_to_int(self._dsa_cdata.priv_key)
+        )
+
+    def public_key(self):
+        dsa_cdata = self._backend._lib.DSA_new()
+        self._backend.openssl_assert(dsa_cdata != self._backend._ffi.NULL)
+        dsa_cdata = self._backend._ffi.gc(
+            dsa_cdata, self._backend._lib.DSA_free
+        )
+        dsa_cdata.p = self._backend._lib.BN_dup(self._dsa_cdata.p)
+        dsa_cdata.q = self._backend._lib.BN_dup(self._dsa_cdata.q)
+        dsa_cdata.g = self._backend._lib.BN_dup(self._dsa_cdata.g)
+        dsa_cdata.pub_key = self._backend._lib.BN_dup(self._dsa_cdata.pub_key)
+        evp_pkey = self._backend._dsa_cdata_to_evp_pkey(dsa_cdata)
+        return _DSAPublicKey(self._backend, dsa_cdata, evp_pkey)
+
+    def parameters(self):
+        dsa_cdata = self._backend._lib.DSA_new()
+        self._backend.openssl_assert(dsa_cdata != self._backend._ffi.NULL)
+        dsa_cdata = self._backend._ffi.gc(
+            dsa_cdata, self._backend._lib.DSA_free
+        )
+        dsa_cdata.p = self._backend._lib.BN_dup(self._dsa_cdata.p)
+        dsa_cdata.q = self._backend._lib.BN_dup(self._dsa_cdata.q)
+        dsa_cdata.g = self._backend._lib.BN_dup(self._dsa_cdata.g)
+        return _DSAParameters(self._backend, dsa_cdata)
+
+    def private_bytes(self, encoding, format, encryption_algorithm):
+        return self._backend._private_key_bytes(
+            encoding,
+            format,
+            encryption_algorithm,
+            self._evp_pkey,
+            self._dsa_cdata
+        )
+
+
+@utils.register_interface(dsa.DSAPublicKeyWithSerialization)
+class _DSAPublicKey(object):
+    def __init__(self, backend, dsa_cdata, evp_pkey):
+        self._backend = backend
+        self._dsa_cdata = dsa_cdata
+        self._evp_pkey = evp_pkey
+        self._key_size = self._backend._lib.BN_num_bits(self._dsa_cdata.p)
+
+    key_size = utils.read_only_property("_key_size")
+
+    def verifier(self, signature, signature_algorithm):
+        if not isinstance(signature, bytes):
+            raise TypeError("signature must be bytes.")
+
+        return _DSAVerificationContext(
+            self._backend, self, signature, signature_algorithm
+        )
+
+    def public_numbers(self):
+        return dsa.DSAPublicNumbers(
+            parameter_numbers=dsa.DSAParameterNumbers(
+                p=self._backend._bn_to_int(self._dsa_cdata.p),
+                q=self._backend._bn_to_int(self._dsa_cdata.q),
+                g=self._backend._bn_to_int(self._dsa_cdata.g)
+            ),
+            y=self._backend._bn_to_int(self._dsa_cdata.pub_key)
+        )
+
+    def parameters(self):
+        dsa_cdata = self._backend._lib.DSA_new()
+        self._backend.openssl_assert(dsa_cdata != self._backend._ffi.NULL)
+        dsa_cdata = self._backend._ffi.gc(
+            dsa_cdata, self._backend._lib.DSA_free
+        )
+        dsa_cdata.p = self._backend._lib.BN_dup(self._dsa_cdata.p)
+        dsa_cdata.q = self._backend._lib.BN_dup(self._dsa_cdata.q)
+        dsa_cdata.g = self._backend._lib.BN_dup(self._dsa_cdata.g)
+        return _DSAParameters(self._backend, dsa_cdata)
+
+    def public_bytes(self, encoding, format):
+        if format is serialization.PublicFormat.PKCS1:
+            raise ValueError(
+                "DSA public keys do not support PKCS1 serialization"
+            )
+
+        return self._backend._public_key_bytes(
+            encoding,
+            format,
+            self._evp_pkey,
+            None
+        )

lib/python3.5/site-packages/cryptography/hazmat/backends/openssl/ec.py

@@ -0,0 +1,299 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+from cryptography import utils
+from cryptography.exceptions import (
+    InvalidSignature, UnsupportedAlgorithm, _Reasons
+)
+from cryptography.hazmat.backends.openssl.utils import _truncate_digest
+from cryptography.hazmat.primitives import hashes, serialization
+from cryptography.hazmat.primitives.asymmetric import (
+    AsymmetricSignatureContext, AsymmetricVerificationContext, ec
+)
+
+
+def _truncate_digest_for_ecdsa(ec_key_cdata, digest, backend):
+    """
+    This function truncates digests that are longer than a given elliptic
+    curve key's length so they can be signed. Since elliptic curve keys are
+    much shorter than RSA keys many digests (e.g. SHA-512) may require
+    truncation.
+    """
+
+    _lib = backend._lib
+    _ffi = backend._ffi
+
+    group = _lib.EC_KEY_get0_group(ec_key_cdata)
+
+    with backend._tmp_bn_ctx() as bn_ctx:
+        order = _lib.BN_CTX_get(bn_ctx)
+        backend.openssl_assert(order != _ffi.NULL)
+
+        res = _lib.EC_GROUP_get_order(group, order, bn_ctx)
+        backend.openssl_assert(res == 1)
+
+        order_bits = _lib.BN_num_bits(order)
+
+    return _truncate_digest(digest, order_bits)
+
+
+def _ec_key_curve_sn(backend, ec_key):
+    group = backend._lib.EC_KEY_get0_group(ec_key)
+    backend.openssl_assert(group != backend._ffi.NULL)
+
+    nid = backend._lib.EC_GROUP_get_curve_name(group)
+    # The following check is to find EC keys with unnamed curves and raise
+    # an error for now.
+    if nid == backend._lib.NID_undef:
+        raise NotImplementedError(
+            "ECDSA certificates with unnamed curves are unsupported "
+            "at this time"
+        )
+
+    curve_name = backend._lib.OBJ_nid2sn(nid)
+    backend.openssl_assert(curve_name != backend._ffi.NULL)
+
+    sn = backend._ffi.string(curve_name).decode('ascii')
+    return sn
+
+
+def _mark_asn1_named_ec_curve(backend, ec_cdata):
+    """
+    Set the named curve flag on the EC_KEY. This causes OpenSSL to
+    serialize EC keys along with their curve OID which makes
+    deserialization easier.
+    """
+
+    backend._lib.EC_KEY_set_asn1_flag(
+        ec_cdata, backend._lib.OPENSSL_EC_NAMED_CURVE
+    )
+
+
+def _sn_to_elliptic_curve(backend, sn):
+    try:
+        return ec._CURVE_TYPES[sn]()
+    except KeyError:
+        raise UnsupportedAlgorithm(
+            "{0} is not a supported elliptic curve".format(sn),
+            _Reasons.UNSUPPORTED_ELLIPTIC_CURVE
+        )
+
+
+@utils.register_interface(AsymmetricSignatureContext)
+class _ECDSASignatureContext(object):
+    def __init__(self, backend, private_key, algorithm):
+        self._backend = backend
+        self._private_key = private_key
+        self._digest = hashes.Hash(algorithm, backend)
+
+    def update(self, data):
+        self._digest.update(data)
+
+    def finalize(self):
+        ec_key = self._private_key._ec_key
+
+        digest = self._digest.finalize()
+
+        digest = _truncate_digest_for_ecdsa(ec_key, digest, self._backend)
+
+        max_size = self._backend._lib.ECDSA_size(ec_key)
+        self._backend.openssl_assert(max_size > 0)
+
+        sigbuf = self._backend._ffi.new("char[]", max_size)
+        siglen_ptr = self._backend._ffi.new("unsigned int[]", 1)
+        res = self._backend._lib.ECDSA_sign(
+            0,
+            digest,
+            len(digest),
+            sigbuf,
+            siglen_ptr,
+            ec_key
+        )
+        self._backend.openssl_assert(res == 1)
+        return self._backend._ffi.buffer(sigbuf)[:siglen_ptr[0]]
+
+
+@utils.register_interface(AsymmetricVerificationContext)
+class _ECDSAVerificationContext(object):
+    def __init__(self, backend, public_key, signature, algorithm):
+        self._backend = backend
+        self._public_key = public_key
+        self._signature = signature
+        self._digest = hashes.Hash(algorithm, backend)
+
+    def update(self, data):
+        self._digest.update(data)
+
+    def verify(self):
+        ec_key = self._public_key._ec_key
+
+        digest = self._digest.finalize()
+
+        digest = _truncate_digest_for_ecdsa(ec_key, digest, self._backend)
+
+        res = self._backend._lib.ECDSA_verify(
+            0,
+            digest,
+            len(digest),
+            self._signature,
+            len(self._signature),
+            ec_key
+        )
+        if res != 1:
+            self._backend._consume_errors()
+            raise InvalidSignature
+        return True
+
+
+@utils.register_interface(ec.EllipticCurvePrivateKeyWithSerialization)
+class _EllipticCurvePrivateKey(object):
+    def __init__(self, backend, ec_key_cdata, evp_pkey):
+        self._backend = backend
+        _mark_asn1_named_ec_curve(backend, ec_key_cdata)
+        self._ec_key = ec_key_cdata
+        self._evp_pkey = evp_pkey
+
+        sn = _ec_key_curve_sn(backend, ec_key_cdata)
+        self._curve = _sn_to_elliptic_curve(backend, sn)
+
+    curve = utils.read_only_property("_curve")
+
+    def signer(self, signature_algorithm):
+        if isinstance(signature_algorithm, ec.ECDSA):
+            return _ECDSASignatureContext(
+                self._backend, self, signature_algorithm.algorithm
+            )
+        else:
+            raise UnsupportedAlgorithm(
+                "Unsupported elliptic curve signature algorithm.",
+                _Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM)
+
+    def exchange(self, algorithm, peer_public_key):
+        if not (
+            self._backend.elliptic_curve_exchange_algorithm_supported(
+                algorithm, self.curve
+            )
+        ):
+            raise UnsupportedAlgorithm(
+                "This backend does not support the ECDH algorithm.",
+                _Reasons.UNSUPPORTED_EXCHANGE_ALGORITHM
+            )
+
+        group = self._backend._lib.EC_KEY_get0_group(self._ec_key)
+        z_len = (self._backend._lib.EC_GROUP_get_degree(group) + 7) // 8
+        self._backend.openssl_assert(z_len > 0)
+        z_buf = self._backend._ffi.new("uint8_t[]", z_len)
+        peer_key = self._backend._lib.EC_KEY_get0_public_key(
+            peer_public_key._ec_key
+        )
+
+        r = self._backend._lib.ECDH_compute_key(
+            z_buf, z_len, peer_key, self._ec_key, self._backend._ffi.NULL
+        )
+        self._backend.openssl_assert(r > 0)
+        return self._backend._ffi.buffer(z_buf)[:z_len]
+
+    def public_key(self):
+        group = self._backend._lib.EC_KEY_get0_group(self._ec_key)
+        self._backend.openssl_assert(group != self._backend._ffi.NULL)
+
+        curve_nid = self._backend._lib.EC_GROUP_get_curve_name(group)
+
+        public_ec_key = self._backend._lib.EC_KEY_new_by_curve_name(curve_nid)
+        self._backend.openssl_assert(public_ec_key != self._backend._ffi.NULL)
+        public_ec_key = self._backend._ffi.gc(
+            public_ec_key, self._backend._lib.EC_KEY_free
+        )
+
+        point = self._backend._lib.EC_KEY_get0_public_key(self._ec_key)
+        self._backend.openssl_assert(point != self._backend._ffi.NULL)
+
+        res = self._backend._lib.EC_KEY_set_public_key(public_ec_key, point)
+        self._backend.openssl_assert(res == 1)
+
+        evp_pkey = self._backend._ec_cdata_to_evp_pkey(public_ec_key)
+
+        return _EllipticCurvePublicKey(self._backend, public_ec_key, evp_pkey)
+
+    def private_numbers(self):
+        bn = self._backend._lib.EC_KEY_get0_private_key(self._ec_key)
+        private_value = self._backend._bn_to_int(bn)
+        return ec.EllipticCurvePrivateNumbers(
+            private_value=private_value,
+            public_numbers=self.public_key().public_numbers()
+        )
+
+    def private_bytes(self, encoding, format, encryption_algorithm):
+        return self._backend._private_key_bytes(
+            encoding,
+            format,
+            encryption_algorithm,
+            self._evp_pkey,
+            self._ec_key
+        )
+
+
+@utils.register_interface(ec.EllipticCurvePublicKeyWithSerialization)
+class _EllipticCurvePublicKey(object):
+    def __init__(self, backend, ec_key_cdata, evp_pkey):
+        self._backend = backend
+        _mark_asn1_named_ec_curve(backend, ec_key_cdata)
+        self._ec_key = ec_key_cdata
+        self._evp_pkey = evp_pkey
+
+        sn = _ec_key_curve_sn(backend, ec_key_cdata)
+        self._curve = _sn_to_elliptic_curve(backend, sn)
+
+    curve = utils.read_only_property("_curve")
+
+    def verifier(self, signature, signature_algorithm):
+        if not isinstance(signature, bytes):
+            raise TypeError("signature must be bytes.")
+
+        if isinstance(signature_algorithm, ec.ECDSA):
+            return _ECDSAVerificationContext(
+                self._backend, self, signature, signature_algorithm.algorithm
+            )
+        else:
+            raise UnsupportedAlgorithm(
+                "Unsupported elliptic curve signature algorithm.",
+                _Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM)
+
+    def public_numbers(self):
+        set_func, get_func, group = (
+            self._backend._ec_key_determine_group_get_set_funcs(self._ec_key)
+        )
+        point = self._backend._lib.EC_KEY_get0_public_key(self._ec_key)
+        self._backend.openssl_assert(point != self._backend._ffi.NULL)
+
+        with self._backend._tmp_bn_ctx() as bn_ctx:
+            bn_x = self._backend._lib.BN_CTX_get(bn_ctx)
+            bn_y = self._backend._lib.BN_CTX_get(bn_ctx)
+
+            res = get_func(group, point, bn_x, bn_y, bn_ctx)
+            self._backend.openssl_assert(res == 1)
+
+            x = self._backend._bn_to_int(bn_x)
+            y = self._backend._bn_to_int(bn_y)
+
+        return ec.EllipticCurvePublicNumbers(
+            x=x,
+            y=y,
+            curve=self._curve
+        )
+
+    def public_bytes(self, encoding, format):
+        if format is serialization.PublicFormat.PKCS1:
+            raise ValueError(
+                "EC public keys do not support PKCS1 serialization"
+            )
+
+        return self._backend._public_key_bytes(
+            encoding,
+            format,
+            self._evp_pkey,
+            None
+        )

lib/python3.5/site-packages/cryptography/hazmat/backends/openssl/hashes.py

@@ -0,0 +1,62 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+
+from cryptography import utils
+from cryptography.exceptions import UnsupportedAlgorithm, _Reasons
+from cryptography.hazmat.primitives import hashes
+
+
+@utils.register_interface(hashes.HashContext)
+class _HashContext(object):
+    def __init__(self, backend, algorithm, ctx=None):
+        self._algorithm = algorithm
+
+        self._backend = backend
+
+        if ctx is None:
+            ctx = self._backend._lib.EVP_MD_CTX_create()
+            ctx = self._backend._ffi.gc(ctx,
+                                        self._backend._lib.EVP_MD_CTX_destroy)
+            evp_md = self._backend._lib.EVP_get_digestbyname(
+                algorithm.name.encode("ascii"))
+            if evp_md == self._backend._ffi.NULL:
+                raise UnsupportedAlgorithm(
+                    "{0} is not a supported hash on this backend.".format(
+                        algorithm.name),
+                    _Reasons.UNSUPPORTED_HASH
+                )
+            res = self._backend._lib.EVP_DigestInit_ex(ctx, evp_md,
+                                                       self._backend._ffi.NULL)
+            self._backend.openssl_assert(res != 0)
+
+        self._ctx = ctx
+
+    algorithm = utils.read_only_property("_algorithm")
+
+    def copy(self):
+        copied_ctx = self._backend._lib.EVP_MD_CTX_create()
+        copied_ctx = self._backend._ffi.gc(
+            copied_ctx, self._backend._lib.EVP_MD_CTX_destroy
+        )
+        res = self._backend._lib.EVP_MD_CTX_copy_ex(copied_ctx, self._ctx)
+        self._backend.openssl_assert(res != 0)
+        return _HashContext(self._backend, self.algorithm, ctx=copied_ctx)
+
+    def update(self, data):
+        res = self._backend._lib.EVP_DigestUpdate(self._ctx, data, len(data))
+        self._backend.openssl_assert(res != 0)
+
+    def finalize(self):
+        buf = self._backend._ffi.new("unsigned char[]",
+                                     self._backend._lib.EVP_MAX_MD_SIZE)
+        outlen = self._backend._ffi.new("unsigned int *")
+        res = self._backend._lib.EVP_DigestFinal_ex(self._ctx, buf, outlen)
+        self._backend.openssl_assert(res != 0)
+        self._backend.openssl_assert(outlen[0] == self.algorithm.digest_size)
+        res = self._backend._lib.EVP_MD_CTX_cleanup(self._ctx)
+        self._backend.openssl_assert(res == 1)
+        return self._backend._ffi.buffer(buf)[:outlen[0]]

lib/python3.5/site-packages/cryptography/hazmat/backends/openssl/hmac.py

@@ -0,0 +1,81 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+
+from cryptography import utils
+from cryptography.exceptions import (
+    InvalidSignature, UnsupportedAlgorithm, _Reasons
+)
+from cryptography.hazmat.primitives import constant_time, hashes, interfaces
+
+
+@utils.register_interface(interfaces.MACContext)
+@utils.register_interface(hashes.HashContext)
+class _HMACContext(object):
+    def __init__(self, backend, key, algorithm, ctx=None):
+        self._algorithm = algorithm
+        self._backend = backend
+
+        if ctx is None:
+            ctx = self._backend._ffi.new("HMAC_CTX *")
+            self._backend._lib.HMAC_CTX_init(ctx)
+            ctx = self._backend._ffi.gc(
+                ctx, self._backend._lib.HMAC_CTX_cleanup
+            )
+            evp_md = self._backend._lib.EVP_get_digestbyname(
+                algorithm.name.encode('ascii'))
+            if evp_md == self._backend._ffi.NULL:
+                raise UnsupportedAlgorithm(
+                    "{0} is not a supported hash on this backend.".format(
+                        algorithm.name),
+                    _Reasons.UNSUPPORTED_HASH
+                )
+            res = self._backend._lib.Cryptography_HMAC_Init_ex(
+                ctx, key, len(key), evp_md, self._backend._ffi.NULL
+            )
+            self._backend.openssl_assert(res != 0)
+
+        self._ctx = ctx
+        self._key = key
+
+    algorithm = utils.read_only_property("_algorithm")
+
+    def copy(self):
+        copied_ctx = self._backend._ffi.new("HMAC_CTX *")
+        self._backend._lib.HMAC_CTX_init(copied_ctx)
+        copied_ctx = self._backend._ffi.gc(
+            copied_ctx, self._backend._lib.HMAC_CTX_cleanup
+        )
+        res = self._backend._lib.Cryptography_HMAC_CTX_copy(
+            copied_ctx, self._ctx
+        )
+        self._backend.openssl_assert(res != 0)
+        return _HMACContext(
+            self._backend, self._key, self.algorithm, ctx=copied_ctx
+        )
+
+    def update(self, data):
+        res = self._backend._lib.Cryptography_HMAC_Update(
+            self._ctx, data, len(data)
+        )
+        self._backend.openssl_assert(res != 0)
+
+    def finalize(self):
+        buf = self._backend._ffi.new("unsigned char[]",
+                                     self._backend._lib.EVP_MAX_MD_SIZE)
+        outlen = self._backend._ffi.new("unsigned int *")
+        res = self._backend._lib.Cryptography_HMAC_Final(
+            self._ctx, buf, outlen
+        )
+        self._backend.openssl_assert(res != 0)
+        self._backend.openssl_assert(outlen[0] == self.algorithm.digest_size)
+        self._backend._lib.HMAC_CTX_cleanup(self._ctx)
+        return self._backend._ffi.buffer(buf)[:outlen[0]]
+
+    def verify(self, signature):
+        digest = self.finalize()
+        if not constant_time.bytes_eq(digest, signature):
+            raise InvalidSignature("Signature did not match digest.")

lib/python3.5/site-packages/cryptography/hazmat/backends/openssl/rsa.py

@@ -0,0 +1,604 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import math
+
+from cryptography import utils
+from cryptography.exceptions import (
+    AlreadyFinalized, InvalidSignature, UnsupportedAlgorithm, _Reasons
+)
+from cryptography.hazmat.primitives import hashes
+from cryptography.hazmat.primitives.asymmetric import (
+    AsymmetricSignatureContext, AsymmetricVerificationContext, rsa
+)
+from cryptography.hazmat.primitives.asymmetric.padding import (
+    AsymmetricPadding, MGF1, OAEP, PKCS1v15, PSS
+)
+from cryptography.hazmat.primitives.asymmetric.rsa import (
+    RSAPrivateKeyWithSerialization, RSAPublicKeyWithSerialization
+)
+
+
+def _get_rsa_pss_salt_length(pss, key_size, digest_size):
+    salt = pss._salt_length
+
+    if salt is MGF1.MAX_LENGTH or salt is PSS.MAX_LENGTH:
+        # bit length - 1 per RFC 3447
+        emlen = int(math.ceil((key_size - 1) / 8.0))
+        salt_length = emlen - digest_size - 2
+        assert salt_length >= 0
+        return salt_length
+    else:
+        return salt
+
+
+def _enc_dec_rsa(backend, key, data, padding):
+    if not isinstance(padding, AsymmetricPadding):
+        raise TypeError("Padding must be an instance of AsymmetricPadding.")
+
+    if isinstance(padding, PKCS1v15):
+        padding_enum = backend._lib.RSA_PKCS1_PADDING
+    elif isinstance(padding, OAEP):
+        padding_enum = backend._lib.RSA_PKCS1_OAEP_PADDING
+        if not isinstance(padding._mgf, MGF1):
+            raise UnsupportedAlgorithm(
+                "Only MGF1 is supported by this backend.",
+                _Reasons.UNSUPPORTED_MGF
+            )
+
+        if not isinstance(padding._mgf._algorithm, hashes.SHA1):
+            raise UnsupportedAlgorithm(
+                "This backend supports only SHA1 inside MGF1 when "
+                "using OAEP.",
+                _Reasons.UNSUPPORTED_HASH
+            )
+
+        if padding._label is not None and padding._label != b"":
+            raise ValueError("This backend does not support OAEP labels.")
+
+        if not isinstance(padding._algorithm, hashes.SHA1):
+            raise UnsupportedAlgorithm(
+                "This backend only supports SHA1 when using OAEP.",
+                _Reasons.UNSUPPORTED_HASH
+            )
+    else:
+        raise UnsupportedAlgorithm(
+            "{0} is not supported by this backend.".format(
+                padding.name
+            ),
+            _Reasons.UNSUPPORTED_PADDING
+        )
+
+    if backend._lib.Cryptography_HAS_PKEY_CTX:
+        return _enc_dec_rsa_pkey_ctx(backend, key, data, padding_enum)
+    else:
+        return _enc_dec_rsa_098(backend, key, data, padding_enum)
+
+
+def _enc_dec_rsa_pkey_ctx(backend, key, data, padding_enum):
+    if isinstance(key, _RSAPublicKey):
+        init = backend._lib.EVP_PKEY_encrypt_init
+        crypt = backend._lib.Cryptography_EVP_PKEY_encrypt
+    else:
+        init = backend._lib.EVP_PKEY_decrypt_init
+        crypt = backend._lib.Cryptography_EVP_PKEY_decrypt
+
+    pkey_ctx = backend._lib.EVP_PKEY_CTX_new(
+        key._evp_pkey, backend._ffi.NULL
+    )
+    backend.openssl_assert(pkey_ctx != backend._ffi.NULL)
+    pkey_ctx = backend._ffi.gc(pkey_ctx, backend._lib.EVP_PKEY_CTX_free)
+    res = init(pkey_ctx)
+    backend.openssl_assert(res == 1)
+    res = backend._lib.EVP_PKEY_CTX_set_rsa_padding(
+        pkey_ctx, padding_enum)
+    backend.openssl_assert(res > 0)
+    buf_size = backend._lib.EVP_PKEY_size(key._evp_pkey)
+    backend.openssl_assert(buf_size > 0)
+    outlen = backend._ffi.new("size_t *", buf_size)
+    buf = backend._ffi.new("char[]", buf_size)
+    res = crypt(pkey_ctx, buf, outlen, data, len(data))
+    if res <= 0:
+        _handle_rsa_enc_dec_error(backend, key)
+
+    return backend._ffi.buffer(buf)[:outlen[0]]
+
+
+def _enc_dec_rsa_098(backend, key, data, padding_enum):
+    if isinstance(key, _RSAPublicKey):
+        crypt = backend._lib.RSA_public_encrypt
+    else:
+        crypt = backend._lib.RSA_private_decrypt
+
+    key_size = backend._lib.RSA_size(key._rsa_cdata)
+    backend.openssl_assert(key_size > 0)
+    buf = backend._ffi.new("unsigned char[]", key_size)
+    res = crypt(len(data), data, buf, key._rsa_cdata, padding_enum)
+    if res < 0:
+        _handle_rsa_enc_dec_error(backend, key)
+
+    return backend._ffi.buffer(buf)[:res]
+
+
+def _handle_rsa_enc_dec_error(backend, key):
+    errors = backend._consume_errors()
+    assert errors
+    assert errors[0].lib == backend._lib.ERR_LIB_RSA
+    if isinstance(key, _RSAPublicKey):
+        assert (errors[0].reason ==
+                backend._lib.RSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE)
+        raise ValueError(
+            "Data too long for key size. Encrypt less data or use a "
+            "larger key size."
+        )
+    else:
+        decoding_errors = [
+            backend._lib.RSA_R_BLOCK_TYPE_IS_NOT_01,
+            backend._lib.RSA_R_BLOCK_TYPE_IS_NOT_02,
+        ]
+        if backend._lib.Cryptography_HAS_RSA_R_PKCS_DECODING_ERROR:
+            decoding_errors.append(backend._lib.RSA_R_PKCS_DECODING_ERROR)
+
+        assert errors[0].reason in decoding_errors
+        raise ValueError("Decryption failed.")
+
+
+@utils.register_interface(AsymmetricSignatureContext)
+class _RSASignatureContext(object):
+    def __init__(self, backend, private_key, padding, algorithm):
+        self._backend = backend
+        self._private_key = private_key
+
+        if not isinstance(padding, AsymmetricPadding):
+            raise TypeError("Expected provider of AsymmetricPadding.")
+
+        self._pkey_size = self._backend._lib.EVP_PKEY_size(
+            self._private_key._evp_pkey
+        )
+        self._backend.openssl_assert(self._pkey_size > 0)
+
+        if isinstance(padding, PKCS1v15):
+            if self._backend._lib.Cryptography_HAS_PKEY_CTX:
+                self._finalize_method = self._finalize_pkey_ctx
+                self._padding_enum = self._backend._lib.RSA_PKCS1_PADDING
+            else:
+                self._finalize_method = self._finalize_pkcs1
+        elif isinstance(padding, PSS):
+            if not isinstance(padding._mgf, MGF1):
+                raise UnsupportedAlgorithm(
+                    "Only MGF1 is supported by this backend.",
+                    _Reasons.UNSUPPORTED_MGF
+                )
+
+            # Size of key in bytes - 2 is the maximum
+            # PSS signature length (salt length is checked later)
+            if self._pkey_size - algorithm.digest_size - 2 < 0:
+                raise ValueError("Digest too large for key size. Use a larger "
+                                 "key.")
+
+            if not self._backend._mgf1_hash_supported(padding._mgf._algorithm):
+                raise UnsupportedAlgorithm(
+                    "When OpenSSL is older than 1.0.1 then only SHA1 is "
+                    "supported with MGF1.",
+                    _Reasons.UNSUPPORTED_HASH
+                )
+
+            if self._backend._lib.Cryptography_HAS_PKEY_CTX:
+                self._finalize_method = self._finalize_pkey_ctx
+                self._padding_enum = self._backend._lib.RSA_PKCS1_PSS_PADDING
+            else:
+                self._finalize_method = self._finalize_pss
+        else:
+            raise UnsupportedAlgorithm(
+                "{0} is not supported by this backend.".format(padding.name),
+                _Reasons.UNSUPPORTED_PADDING
+            )
+
+        self._padding = padding
+        self._algorithm = algorithm
+        self._hash_ctx = hashes.Hash(self._algorithm, self._backend)
+
+    def update(self, data):
+        self._hash_ctx.update(data)
+
+    def finalize(self):
+        evp_md = self._backend._lib.EVP_get_digestbyname(
+            self._algorithm.name.encode("ascii"))
+        self._backend.openssl_assert(evp_md != self._backend._ffi.NULL)
+
+        return self._finalize_method(evp_md)
+
+    def _finalize_pkey_ctx(self, evp_md):
+        pkey_ctx = self._backend._lib.EVP_PKEY_CTX_new(
+            self._private_key._evp_pkey, self._backend._ffi.NULL
+        )
+        self._backend.openssl_assert(pkey_ctx != self._backend._ffi.NULL)
+        pkey_ctx = self._backend._ffi.gc(pkey_ctx,
+                                         self._backend._lib.EVP_PKEY_CTX_free)
+        res = self._backend._lib.EVP_PKEY_sign_init(pkey_ctx)
+        self._backend.openssl_assert(res == 1)
+        res = self._backend._lib.EVP_PKEY_CTX_set_signature_md(
+            pkey_ctx, evp_md)
+        self._backend.openssl_assert(res > 0)
+
+        res = self._backend._lib.EVP_PKEY_CTX_set_rsa_padding(
+            pkey_ctx, self._padding_enum)
+        self._backend.openssl_assert(res > 0)
+        if isinstance(self._padding, PSS):
+            res = self._backend._lib.EVP_PKEY_CTX_set_rsa_pss_saltlen(
+                pkey_ctx,
+                _get_rsa_pss_salt_length(
+                    self._padding,
+                    self._private_key.key_size,
+                    self._hash_ctx.algorithm.digest_size
+                )
+            )
+            self._backend.openssl_assert(res > 0)
+
+            if self._backend._lib.Cryptography_HAS_MGF1_MD:
+                # MGF1 MD is configurable in OpenSSL 1.0.1+
+                mgf1_md = self._backend._lib.EVP_get_digestbyname(
+                    self._padding._mgf._algorithm.name.encode("ascii"))
+                self._backend.openssl_assert(
+                    mgf1_md != self._backend._ffi.NULL
+                )
+                res = self._backend._lib.EVP_PKEY_CTX_set_rsa_mgf1_md(
+                    pkey_ctx, mgf1_md
+                )
+                self._backend.openssl_assert(res > 0)
+        data_to_sign = self._hash_ctx.finalize()
+        buflen = self._backend._ffi.new("size_t *")
+        res = self._backend._lib.EVP_PKEY_sign(
+            pkey_ctx,
+            self._backend._ffi.NULL,
+            buflen,
+            data_to_sign,
+            len(data_to_sign)
+        )
+        self._backend.openssl_assert(res == 1)
+        buf = self._backend._ffi.new("unsigned char[]", buflen[0])
+        res = self._backend._lib.EVP_PKEY_sign(
+            pkey_ctx, buf, buflen, data_to_sign, len(data_to_sign))
+        if res != 1:
+            errors = self._backend._consume_errors()
+            assert errors[0].lib == self._backend._lib.ERR_LIB_RSA
+            reason = None
+            if (errors[0].reason ==
+                    self._backend._lib.RSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE):
+                reason = ("Salt length too long for key size. Try using "
+                          "MAX_LENGTH instead.")
+            else:
+                assert (errors[0].reason ==
+                        self._backend._lib.RSA_R_DIGEST_TOO_BIG_FOR_RSA_KEY)
+                reason = "Digest too large for key size. Use a larger key."
+            assert reason is not None
+            raise ValueError(reason)
+
+        return self._backend._ffi.buffer(buf)[:]
+
+    def _finalize_pkcs1(self, evp_md):
+        if self._hash_ctx._ctx is None:
+            raise AlreadyFinalized("Context has already been finalized.")
+
+        sig_buf = self._backend._ffi.new("char[]", self._pkey_size)
+        sig_len = self._backend._ffi.new("unsigned int *")
+        res = self._backend._lib.EVP_SignFinal(
+            self._hash_ctx._ctx._ctx,
+            sig_buf,
+            sig_len,
+            self._private_key._evp_pkey
+        )
+        self._hash_ctx.finalize()
+        if res == 0:
+            errors = self._backend._consume_errors()
+            assert errors[0].lib == self._backend._lib.ERR_LIB_RSA
+            assert (errors[0].reason ==
+                    self._backend._lib.RSA_R_DIGEST_TOO_BIG_FOR_RSA_KEY)
+            raise ValueError("Digest too large for key size. Use a larger "
+                             "key.")
+
+        return self._backend._ffi.buffer(sig_buf)[:sig_len[0]]
+
+    def _finalize_pss(self, evp_md):
+        data_to_sign = self._hash_ctx.finalize()
+        padded = self._backend._ffi.new("unsigned char[]", self._pkey_size)
+        res = self._backend._lib.RSA_padding_add_PKCS1_PSS(
+            self._private_key._rsa_cdata,
+            padded,
+            data_to_sign,
+            evp_md,
+            _get_rsa_pss_salt_length(
+                self._padding,
+                self._private_key.key_size,
+                len(data_to_sign)
+            )
+        )
+        if res != 1:
+            errors = self._backend._consume_errors()
+            assert errors[0].lib == self._backend._lib.ERR_LIB_RSA
+            assert (errors[0].reason ==
+                    self._backend._lib.RSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE)
+            raise ValueError("Salt length too long for key size. Try using "
+                             "MAX_LENGTH instead.")
+
+        sig_buf = self._backend._ffi.new("char[]", self._pkey_size)
+        sig_len = self._backend._lib.RSA_private_encrypt(
+            self._pkey_size,
+            padded,
+            sig_buf,
+            self._private_key._rsa_cdata,
+            self._backend._lib.RSA_NO_PADDING
+        )
+        self._backend.openssl_assert(sig_len != -1)
+        return self._backend._ffi.buffer(sig_buf)[:sig_len]
+
+
+@utils.register_interface(AsymmetricVerificationContext)
+class _RSAVerificationContext(object):
+    def __init__(self, backend, public_key, signature, padding, algorithm):
+        self._backend = backend
+        self._public_key = public_key
+        self._signature = signature
+
+        if not isinstance(padding, AsymmetricPadding):
+            raise TypeError("Expected provider of AsymmetricPadding.")
+
+        self._pkey_size = self._backend._lib.EVP_PKEY_size(
+            self._public_key._evp_pkey
+        )
+        self._backend.openssl_assert(self._pkey_size > 0)
+
+        if isinstance(padding, PKCS1v15):
+            if self._backend._lib.Cryptography_HAS_PKEY_CTX:
+                self._verify_method = self._verify_pkey_ctx
+                self._padding_enum = self._backend._lib.RSA_PKCS1_PADDING
+            else:
+                self._verify_method = self._verify_pkcs1
+        elif isinstance(padding, PSS):
+            if not isinstance(padding._mgf, MGF1):
+                raise UnsupportedAlgorithm(
+                    "Only MGF1 is supported by this backend.",
+                    _Reasons.UNSUPPORTED_MGF
+                )
+
+            # Size of key in bytes - 2 is the maximum
+            # PSS signature length (salt length is checked later)
+            if self._pkey_size - algorithm.digest_size - 2 < 0:
+                raise ValueError(
+                    "Digest too large for key size. Check that you have the "
+                    "correct key and digest algorithm."
+                )
+
+            if not self._backend._mgf1_hash_supported(padding._mgf._algorithm):
+                raise UnsupportedAlgorithm(
+                    "When OpenSSL is older than 1.0.1 then only SHA1 is "
+                    "supported with MGF1.",
+                    _Reasons.UNSUPPORTED_HASH
+                )
+
+            if self._backend._lib.Cryptography_HAS_PKEY_CTX:
+                self._verify_method = self._verify_pkey_ctx
+                self._padding_enum = self._backend._lib.RSA_PKCS1_PSS_PADDING
+            else:
+                self._verify_method = self._verify_pss
+        else:
+            raise UnsupportedAlgorithm(
+                "{0} is not supported by this backend.".format(padding.name),
+                _Reasons.UNSUPPORTED_PADDING
+            )
+
+        self._padding = padding
+        self._algorithm = algorithm
+        self._hash_ctx = hashes.Hash(self._algorithm, self._backend)
+
+    def update(self, data):
+        self._hash_ctx.update(data)
+
+    def verify(self):
+        evp_md = self._backend._lib.EVP_get_digestbyname(
+            self._algorithm.name.encode("ascii"))
+        self._backend.openssl_assert(evp_md != self._backend._ffi.NULL)
+
+        self._verify_method(evp_md)
+
+    def _verify_pkey_ctx(self, evp_md):
+        pkey_ctx = self._backend._lib.EVP_PKEY_CTX_new(
+            self._public_key._evp_pkey, self._backend._ffi.NULL
+        )
+        self._backend.openssl_assert(pkey_ctx != self._backend._ffi.NULL)
+        pkey_ctx = self._backend._ffi.gc(pkey_ctx,
+                                         self._backend._lib.EVP_PKEY_CTX_free)
+        res = self._backend._lib.EVP_PKEY_verify_init(pkey_ctx)
+        self._backend.openssl_assert(res == 1)
+        res = self._backend._lib.EVP_PKEY_CTX_set_signature_md(
+            pkey_ctx, evp_md)
+        self._backend.openssl_assert(res > 0)
+
+        res = self._backend._lib.EVP_PKEY_CTX_set_rsa_padding(
+            pkey_ctx, self._padding_enum)
+        self._backend.openssl_assert(res > 0)
+        if isinstance(self._padding, PSS):
+            res = self._backend._lib.EVP_PKEY_CTX_set_rsa_pss_saltlen(
+                pkey_ctx,
+                _get_rsa_pss_salt_length(
+                    self._padding,
+                    self._public_key.key_size,
+                    self._hash_ctx.algorithm.digest_size
+                )
+            )
+            self._backend.openssl_assert(res > 0)
+            if self._backend._lib.Cryptography_HAS_MGF1_MD:
+                # MGF1 MD is configurable in OpenSSL 1.0.1+
+                mgf1_md = self._backend._lib.EVP_get_digestbyname(
+                    self._padding._mgf._algorithm.name.encode("ascii"))
+                self._backend.openssl_assert(
+                    mgf1_md != self._backend._ffi.NULL
+                )
+                res = self._backend._lib.EVP_PKEY_CTX_set_rsa_mgf1_md(
+                    pkey_ctx, mgf1_md
+                )
+                self._backend.openssl_assert(res > 0)
+
+        data_to_verify = self._hash_ctx.finalize()
+        res = self._backend._lib.EVP_PKEY_verify(
+            pkey_ctx,
+            self._signature,
+            len(self._signature),
+            data_to_verify,
+            len(data_to_verify)
+        )
+        # The previous call can return negative numbers in the event of an
+        # error. This is not a signature failure but we need to fail if it
+        # occurs.
+        self._backend.openssl_assert(res >= 0)
+        if res == 0:
+            errors = self._backend._consume_errors()
+            assert errors
+            raise InvalidSignature
+
+    def _verify_pkcs1(self, evp_md):
+        if self._hash_ctx._ctx is None:
+            raise AlreadyFinalized("Context has already been finalized.")
+
+        res = self._backend._lib.EVP_VerifyFinal(
+            self._hash_ctx._ctx._ctx,
+            self._signature,
+            len(self._signature),
+            self._public_key._evp_pkey
+        )
+        self._hash_ctx.finalize()
+        # The previous call can return negative numbers in the event of an
+        # error. This is not a signature failure but we need to fail if it
+        # occurs.
+        self._backend.openssl_assert(res >= 0)
+        if res == 0:
+            errors = self._backend._consume_errors()
+            assert errors
+            raise InvalidSignature
+
+    def _verify_pss(self, evp_md):
+        buf = self._backend._ffi.new("unsigned char[]", self._pkey_size)
+        res = self._backend._lib.RSA_public_decrypt(
+            len(self._signature),
+            self._signature,
+            buf,
+            self._public_key._rsa_cdata,
+            self._backend._lib.RSA_NO_PADDING
+        )
+        if res != self._pkey_size:
+            errors = self._backend._consume_errors()
+            assert errors
+            raise InvalidSignature
+
+        data_to_verify = self._hash_ctx.finalize()
+        res = self._backend._lib.RSA_verify_PKCS1_PSS(
+            self._public_key._rsa_cdata,
+            data_to_verify,
+            evp_md,
+            buf,
+            _get_rsa_pss_salt_length(
+                self._padding,
+                self._public_key.key_size,
+                len(data_to_verify)
+            )
+        )
+        if res != 1:
+            errors = self._backend._consume_errors()
+            assert errors
+            raise InvalidSignature
+
+
+@utils.register_interface(RSAPrivateKeyWithSerialization)
+class _RSAPrivateKey(object):
+    def __init__(self, backend, rsa_cdata, evp_pkey):
+        self._backend = backend
+        self._rsa_cdata = rsa_cdata
+        self._evp_pkey = evp_pkey
+
+        self._key_size = self._backend._lib.BN_num_bits(self._rsa_cdata.n)
+
+    key_size = utils.read_only_property("_key_size")
+
+    def signer(self, padding, algorithm):
+        return _RSASignatureContext(self._backend, self, padding, algorithm)
+
+    def decrypt(self, ciphertext, padding):
+        key_size_bytes = int(math.ceil(self.key_size / 8.0))
+        if key_size_bytes != len(ciphertext):
+            raise ValueError("Ciphertext length must be equal to key size.")
+
+        return _enc_dec_rsa(self._backend, self, ciphertext, padding)
+
+    def public_key(self):
+        ctx = self._backend._lib.RSA_new()
+        self._backend.openssl_assert(ctx != self._backend._ffi.NULL)
+        ctx = self._backend._ffi.gc(ctx, self._backend._lib.RSA_free)
+        ctx.e = self._backend._lib.BN_dup(self._rsa_cdata.e)
+        ctx.n = self._backend._lib.BN_dup(self._rsa_cdata.n)
+        res = self._backend._lib.RSA_blinding_on(ctx, self._backend._ffi.NULL)
+        self._backend.openssl_assert(res == 1)
+        evp_pkey = self._backend._rsa_cdata_to_evp_pkey(ctx)
+        return _RSAPublicKey(self._backend, ctx, evp_pkey)
+
+    def private_numbers(self):
+        return rsa.RSAPrivateNumbers(
+            p=self._backend._bn_to_int(self._rsa_cdata.p),
+            q=self._backend._bn_to_int(self._rsa_cdata.q),
+            d=self._backend._bn_to_int(self._rsa_cdata.d),
+            dmp1=self._backend._bn_to_int(self._rsa_cdata.dmp1),
+            dmq1=self._backend._bn_to_int(self._rsa_cdata.dmq1),
+            iqmp=self._backend._bn_to_int(self._rsa_cdata.iqmp),
+            public_numbers=rsa.RSAPublicNumbers(
+                e=self._backend._bn_to_int(self._rsa_cdata.e),
+                n=self._backend._bn_to_int(self._rsa_cdata.n),
+            )
+        )
+
+    def private_bytes(self, encoding, format, encryption_algorithm):
+        return self._backend._private_key_bytes(
+            encoding,
+            format,
+            encryption_algorithm,
+            self._evp_pkey,
+            self._rsa_cdata
+        )
+
+
+@utils.register_interface(RSAPublicKeyWithSerialization)
+class _RSAPublicKey(object):
+    def __init__(self, backend, rsa_cdata, evp_pkey):
+        self._backend = backend
+        self._rsa_cdata = rsa_cdata
+        self._evp_pkey = evp_pkey
+
+        self._key_size = self._backend._lib.BN_num_bits(self._rsa_cdata.n)
+
+    key_size = utils.read_only_property("_key_size")
+
+    def verifier(self, signature, padding, algorithm):
+        if not isinstance(signature, bytes):
+            raise TypeError("signature must be bytes.")
+
+        return _RSAVerificationContext(
+            self._backend, self, signature, padding, algorithm
+        )
+
+    def encrypt(self, plaintext, padding):
+        return _enc_dec_rsa(self._backend, self, plaintext, padding)
+
+    def public_numbers(self):
+        return rsa.RSAPublicNumbers(
+            e=self._backend._bn_to_int(self._rsa_cdata.e),
+            n=self._backend._bn_to_int(self._rsa_cdata.n),
+        )
+
+    def public_bytes(self, encoding, format):
+        return self._backend._public_key_bytes(
+            encoding,
+            format,
+            self._evp_pkey,
+            self._rsa_cdata
+        )

lib/python3.5/site-packages/cryptography/hazmat/backends/openssl/utils.py

@@ -0,0 +1,26 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import six
+
+
+def _truncate_digest(digest, order_bits):
+    digest_len = len(digest)
+
+    if 8 * digest_len > order_bits:
+        digest_len = (order_bits + 7) // 8
+        digest = digest[:digest_len]
+
+    if 8 * digest_len > order_bits:
+        rshift = 8 - (order_bits & 0x7)
+        assert 0 < rshift < 8
+
+        mask = 0xFF >> rshift << rshift
+
+        # Set the bottom rshift bits to 0
+        digest = digest[:-1] + six.int2byte(six.indexbytes(digest, -1) & mask)
+
+    return digest

lib/python3.5/site-packages/cryptography/hazmat/backends/openssl/x509.py

@@ -0,0 +1,940 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import datetime
+import ipaddress
+
+from email.utils import parseaddr
+
+import idna
+
+import six
+
+from six.moves import urllib_parse
+
+from cryptography import utils, x509
+from cryptography.exceptions import UnsupportedAlgorithm
+from cryptography.hazmat.primitives import hashes, serialization
+from cryptography.x509.oid import (
+    CRLExtensionOID, CertificatePoliciesOID, ExtensionOID
+)
+
+
+def _obj2txt(backend, obj):
+    # Set to 80 on the recommendation of
+    # https://www.openssl.org/docs/crypto/OBJ_nid2ln.html#return_values
+    buf_len = 80
+    buf = backend._ffi.new("char[]", buf_len)
+    res = backend._lib.OBJ_obj2txt(buf, buf_len, obj, 1)
+    backend.openssl_assert(res > 0)
+    return backend._ffi.buffer(buf, res)[:].decode()
+
+
+def _decode_x509_name_entry(backend, x509_name_entry):
+    obj = backend._lib.X509_NAME_ENTRY_get_object(x509_name_entry)
+    backend.openssl_assert(obj != backend._ffi.NULL)
+    data = backend._lib.X509_NAME_ENTRY_get_data(x509_name_entry)
+    backend.openssl_assert(data != backend._ffi.NULL)
+    value = backend._asn1_string_to_utf8(data)
+    oid = _obj2txt(backend, obj)
+
+    return x509.NameAttribute(x509.ObjectIdentifier(oid), value)
+
+
+def _decode_x509_name(backend, x509_name):
+    count = backend._lib.X509_NAME_entry_count(x509_name)
+    attributes = []
+    for x in range(count):
+        entry = backend._lib.X509_NAME_get_entry(x509_name, x)
+        attributes.append(_decode_x509_name_entry(backend, entry))
+
+    return x509.Name(attributes)
+
+
+def _decode_general_names(backend, gns):
+    num = backend._lib.sk_GENERAL_NAME_num(gns)
+    names = []
+    for i in range(num):
+        gn = backend._lib.sk_GENERAL_NAME_value(gns, i)
+        backend.openssl_assert(gn != backend._ffi.NULL)
+        names.append(_decode_general_name(backend, gn))
+
+    return names
+
+
+def _decode_general_name(backend, gn):
+    if gn.type == backend._lib.GEN_DNS:
+        data = backend._asn1_string_to_bytes(gn.d.dNSName)
+        if not data:
+            decoded = u""
+        elif data.startswith(b"*."):
+            # This is a wildcard name. We need to remove the leading wildcard,
+            # IDNA decode, then re-add the wildcard. Wildcard characters should
+            # always be left-most (RFC 2595 section 2.4).
+            decoded = u"*." + idna.decode(data[2:])
+        else:
+            # Not a wildcard, decode away. If the string has a * in it anywhere
+            # invalid this will raise an InvalidCodePoint
+            decoded = idna.decode(data)
+            if data.startswith(b"."):
+                # idna strips leading periods. Name constraints can have that
+                # so we need to re-add it. Sigh.
+                decoded = u"." + decoded
+
+        return x509.DNSName(decoded)
+    elif gn.type == backend._lib.GEN_URI:
+        data = backend._asn1_string_to_ascii(gn.d.uniformResourceIdentifier)
+        parsed = urllib_parse.urlparse(data)
+        if parsed.hostname:
+            hostname = idna.decode(parsed.hostname)
+        else:
+            hostname = ""
+        if parsed.port:
+            netloc = hostname + u":" + six.text_type(parsed.port)
+        else:
+            netloc = hostname
+
+        # Note that building a URL in this fashion means it should be
+        # semantically indistinguishable from the original but is not
+        # guaranteed to be exactly the same.
+        uri = urllib_parse.urlunparse((
+            parsed.scheme,
+            netloc,
+            parsed.path,
+            parsed.params,
+            parsed.query,
+            parsed.fragment
+        ))
+        return x509.UniformResourceIdentifier(uri)
+    elif gn.type == backend._lib.GEN_RID:
+        oid = _obj2txt(backend, gn.d.registeredID)
+        return x509.RegisteredID(x509.ObjectIdentifier(oid))
+    elif gn.type == backend._lib.GEN_IPADD:
+        data = backend._asn1_string_to_bytes(gn.d.iPAddress)
+        data_len = len(data)
+        if data_len == 8 or data_len == 32:
+            # This is an IPv4 or IPv6 Network and not a single IP. This
+            # type of data appears in Name Constraints. Unfortunately,
+            # ipaddress doesn't support packed bytes + netmask. Additionally,
+            # IPv6Network can only handle CIDR rather than the full 16 byte
+            # netmask. To handle this we convert the netmask to integer, then
+            # find the first 0 bit, which will be the prefix. If another 1
+            # bit is present after that the netmask is invalid.
+            base = ipaddress.ip_address(data[:data_len // 2])
+            netmask = ipaddress.ip_address(data[data_len // 2:])
+            bits = bin(int(netmask))[2:]
+            prefix = bits.find('0')
+            # If no 0 bits are found it is a /32 or /128
+            if prefix == -1:
+                prefix = len(bits)
+
+            if "1" in bits[prefix:]:
+                raise ValueError("Invalid netmask")
+
+            ip = ipaddress.ip_network(base.exploded + u"/{0}".format(prefix))
+        else:
+            ip = ipaddress.ip_address(data)
+
+        return x509.IPAddress(ip)
+    elif gn.type == backend._lib.GEN_DIRNAME:
+        return x509.DirectoryName(
+            _decode_x509_name(backend, gn.d.directoryName)
+        )
+    elif gn.type == backend._lib.GEN_EMAIL:
+        data = backend._asn1_string_to_ascii(gn.d.rfc822Name)
+        name, address = parseaddr(data)
+        parts = address.split(u"@")
+        if name or not address:
+            # parseaddr has found a name (e.g. Name <email>) or the entire
+            # value is an empty string.
+            raise ValueError("Invalid rfc822name value")
+        elif len(parts) == 1:
+            # Single label email name. This is valid for local delivery. No
+            # IDNA decoding can be done since there is no domain component.
+            return x509.RFC822Name(address)
+        else:
+            # A normal email of the form user@domain.com. Let's attempt to
+            # decode the domain component and return the entire address.
+            return x509.RFC822Name(
+                parts[0] + u"@" + idna.decode(parts[1])
+            )
+    elif gn.type == backend._lib.GEN_OTHERNAME:
+        type_id = _obj2txt(backend, gn.d.otherName.type_id)
+        value = backend._asn1_to_der(gn.d.otherName.value)
+        return x509.OtherName(x509.ObjectIdentifier(type_id), value)
+    else:
+        # x400Address or ediPartyName
+        raise x509.UnsupportedGeneralNameType(
+            "{0} is not a supported type".format(
+                x509._GENERAL_NAMES.get(gn.type, gn.type)
+            ),
+            gn.type
+        )
+
+
+def _decode_ocsp_no_check(backend, ext):
+    return x509.OCSPNoCheck()
+
+
+class _X509ExtensionParser(object):
+    def __init__(self, ext_count, get_ext, handlers, unsupported_exts=None):
+        self.ext_count = ext_count
+        self.get_ext = get_ext
+        self.handlers = handlers
+        self.unsupported_exts = unsupported_exts
+
+    def parse(self, backend, x509_obj):
+        extensions = []
+        seen_oids = set()
+        for i in range(self.ext_count(backend, x509_obj)):
+            ext = self.get_ext(backend, x509_obj, i)
+            backend.openssl_assert(ext != backend._ffi.NULL)
+            crit = backend._lib.X509_EXTENSION_get_critical(ext)
+            critical = crit == 1
+            oid = x509.ObjectIdentifier(_obj2txt(backend, ext.object))
+            if oid in seen_oids:
+                raise x509.DuplicateExtension(
+                    "Duplicate {0} extension found".format(oid), oid
+                )
+            try:
+                handler = self.handlers[oid]
+            except KeyError:
+                if critical:
+                    raise x509.UnsupportedExtension(
+                        "Critical extension {0} is not currently supported"
+                        .format(oid), oid
+                    )
+            else:
+                # For extensions which are not supported by OpenSSL we pass the
+                # extension object directly to the parsing routine so it can
+                # be decoded manually.
+                if self.unsupported_exts and oid in self.unsupported_exts:
+                    ext_data = ext
+                else:
+                    ext_data = backend._lib.X509V3_EXT_d2i(ext)
+                    if ext_data == backend._ffi.NULL:
+                        backend._consume_errors()
+                        raise ValueError(
+                            "The {0} extension is invalid and can't be "
+                            "parsed".format(oid)
+                        )
+
+                value = handler(backend, ext_data)
+                extensions.append(x509.Extension(oid, critical, value))
+
+            seen_oids.add(oid)
+
+        return x509.Extensions(extensions)
+
+
+@utils.register_interface(x509.Certificate)
+class _Certificate(object):
+    def __init__(self, backend, x509):
+        self._backend = backend
+        self._x509 = x509
+
+    def __repr__(self):
+        return "<Certificate(subject={0}, ...)>".format(self.subject)
+
+    def __eq__(self, other):
+        if not isinstance(other, x509.Certificate):
+            return NotImplemented
+
+        res = self._backend._lib.X509_cmp(self._x509, other._x509)
+        return res == 0
+
+    def __ne__(self, other):
+        return not self == other
+
+    def __hash__(self):
+        return hash(self.public_bytes(serialization.Encoding.DER))
+
+    def fingerprint(self, algorithm):
+        h = hashes.Hash(algorithm, self._backend)
+        h.update(self.public_bytes(serialization.Encoding.DER))
+        return h.finalize()
+
+    @property
+    def version(self):
+        version = self._backend._lib.X509_get_version(self._x509)
+        if version == 0:
+            return x509.Version.v1
+        elif version == 2:
+            return x509.Version.v3
+        else:
+            raise x509.InvalidVersion(
+                "{0} is not a valid X509 version".format(version), version
+            )
+
+    @property
+    def serial(self):
+        asn1_int = self._backend._lib.X509_get_serialNumber(self._x509)
+        self._backend.openssl_assert(asn1_int != self._backend._ffi.NULL)
+        return self._backend._asn1_integer_to_int(asn1_int)
+
+    def public_key(self):
+        pkey = self._backend._lib.X509_get_pubkey(self._x509)
+        if pkey == self._backend._ffi.NULL:
+            # Remove errors from the stack.
+            self._backend._consume_errors()
+            raise ValueError("Certificate public key is of an unknown type")
+
+        pkey = self._backend._ffi.gc(pkey, self._backend._lib.EVP_PKEY_free)
+
+        return self._backend._evp_pkey_to_public_key(pkey)
+
+    @property
+    def not_valid_before(self):
+        asn1_time = self._backend._lib.X509_get_notBefore(self._x509)
+        return self._backend._parse_asn1_time(asn1_time)
+
+    @property
+    def not_valid_after(self):
+        asn1_time = self._backend._lib.X509_get_notAfter(self._x509)
+        return self._backend._parse_asn1_time(asn1_time)
+
+    @property
+    def issuer(self):
+        issuer = self._backend._lib.X509_get_issuer_name(self._x509)
+        self._backend.openssl_assert(issuer != self._backend._ffi.NULL)
+        return _decode_x509_name(self._backend, issuer)
+
+    @property
+    def subject(self):
+        subject = self._backend._lib.X509_get_subject_name(self._x509)
+        self._backend.openssl_assert(subject != self._backend._ffi.NULL)
+        return _decode_x509_name(self._backend, subject)
+
+    @property
+    def signature_hash_algorithm(self):
+        oid = _obj2txt(self._backend, self._x509.sig_alg.algorithm)
+        try:
+            return x509._SIG_OIDS_TO_HASH[oid]
+        except KeyError:
+            raise UnsupportedAlgorithm(
+                "Signature algorithm OID:{0} not recognized".format(oid)
+            )
+
+    @property
+    def extensions(self):
+        return _CERTIFICATE_EXTENSION_PARSER.parse(self._backend, self._x509)
+
+    def public_bytes(self, encoding):
+        bio = self._backend._create_mem_bio()
+        if encoding is serialization.Encoding.PEM:
+            res = self._backend._lib.PEM_write_bio_X509(bio, self._x509)
+        elif encoding is serialization.Encoding.DER:
+            res = self._backend._lib.i2d_X509_bio(bio, self._x509)
+        else:
+            raise TypeError("encoding must be an item from the Encoding enum")
+
+        self._backend.openssl_assert(res == 1)
+        return self._backend._read_mem_bio(bio)
+
+
+def _decode_certificate_policies(backend, cp):
+    cp = backend._ffi.cast("Cryptography_STACK_OF_POLICYINFO *", cp)
+    cp = backend._ffi.gc(cp, backend._lib.sk_POLICYINFO_free)
+    num = backend._lib.sk_POLICYINFO_num(cp)
+    certificate_policies = []
+    for i in range(num):
+        qualifiers = None
+        pi = backend._lib.sk_POLICYINFO_value(cp, i)
+        oid = x509.ObjectIdentifier(_obj2txt(backend, pi.policyid))
+        if pi.qualifiers != backend._ffi.NULL:
+            qnum = backend._lib.sk_POLICYQUALINFO_num(pi.qualifiers)
+            qualifiers = []
+            for j in range(qnum):
+                pqi = backend._lib.sk_POLICYQUALINFO_value(
+                    pi.qualifiers, j
+                )
+                pqualid = x509.ObjectIdentifier(
+                    _obj2txt(backend, pqi.pqualid)
+                )
+                if pqualid == CertificatePoliciesOID.CPS_QUALIFIER:
+                    cpsuri = backend._ffi.buffer(
+                        pqi.d.cpsuri.data, pqi.d.cpsuri.length
+                    )[:].decode('ascii')
+                    qualifiers.append(cpsuri)
+                else:
+                    assert pqualid == CertificatePoliciesOID.CPS_USER_NOTICE
+                    user_notice = _decode_user_notice(
+                        backend, pqi.d.usernotice
+                    )
+                    qualifiers.append(user_notice)
+
+        certificate_policies.append(
+            x509.PolicyInformation(oid, qualifiers)
+        )
+
+    return x509.CertificatePolicies(certificate_policies)
+
+
+def _decode_user_notice(backend, un):
+    explicit_text = None
+    notice_reference = None
+
+    if un.exptext != backend._ffi.NULL:
+        explicit_text = backend._asn1_string_to_utf8(un.exptext)
+
+    if un.noticeref != backend._ffi.NULL:
+        organization = backend._asn1_string_to_utf8(un.noticeref.organization)
+
+        num = backend._lib.sk_ASN1_INTEGER_num(
+            un.noticeref.noticenos
+        )
+        notice_numbers = []
+        for i in range(num):
+            asn1_int = backend._lib.sk_ASN1_INTEGER_value(
+                un.noticeref.noticenos, i
+            )
+            notice_num = backend._asn1_integer_to_int(asn1_int)
+            notice_numbers.append(notice_num)
+
+        notice_reference = x509.NoticeReference(
+            organization, notice_numbers
+        )
+
+    return x509.UserNotice(notice_reference, explicit_text)
+
+
+def _decode_basic_constraints(backend, bc_st):
+    basic_constraints = backend._ffi.cast("BASIC_CONSTRAINTS *", bc_st)
+    basic_constraints = backend._ffi.gc(
+        basic_constraints, backend._lib.BASIC_CONSTRAINTS_free
+    )
+    # The byte representation of an ASN.1 boolean true is \xff. OpenSSL
+    # chooses to just map this to its ordinal value, so true is 255 and
+    # false is 0.
+    ca = basic_constraints.ca == 255
+    if basic_constraints.pathlen == backend._ffi.NULL:
+        path_length = None
+    else:
+        path_length = backend._asn1_integer_to_int(basic_constraints.pathlen)
+
+    return x509.BasicConstraints(ca, path_length)
+
+
+def _decode_subject_key_identifier(backend, asn1_string):
+    asn1_string = backend._ffi.cast("ASN1_OCTET_STRING *", asn1_string)
+    asn1_string = backend._ffi.gc(
+        asn1_string, backend._lib.ASN1_OCTET_STRING_free
+    )
+    return x509.SubjectKeyIdentifier(
+        backend._ffi.buffer(asn1_string.data, asn1_string.length)[:]
+    )
+
+
+def _decode_authority_key_identifier(backend, akid):
+    akid = backend._ffi.cast("AUTHORITY_KEYID *", akid)
+    akid = backend._ffi.gc(akid, backend._lib.AUTHORITY_KEYID_free)
+    key_identifier = None
+    authority_cert_issuer = None
+    authority_cert_serial_number = None
+
+    if akid.keyid != backend._ffi.NULL:
+        key_identifier = backend._ffi.buffer(
+            akid.keyid.data, akid.keyid.length
+        )[:]
+
+    if akid.issuer != backend._ffi.NULL:
+        authority_cert_issuer = _decode_general_names(
+            backend, akid.issuer
+        )
+
+    if akid.serial != backend._ffi.NULL:
+        authority_cert_serial_number = backend._asn1_integer_to_int(
+            akid.serial
+        )
+
+    return x509.AuthorityKeyIdentifier(
+        key_identifier, authority_cert_issuer, authority_cert_serial_number
+    )
+
+
+def _decode_authority_information_access(backend, aia):
+    aia = backend._ffi.cast("Cryptography_STACK_OF_ACCESS_DESCRIPTION *", aia)
+    aia = backend._ffi.gc(aia, backend._lib.sk_ACCESS_DESCRIPTION_free)
+    num = backend._lib.sk_ACCESS_DESCRIPTION_num(aia)
+    access_descriptions = []
+    for i in range(num):
+        ad = backend._lib.sk_ACCESS_DESCRIPTION_value(aia, i)
+        backend.openssl_assert(ad.method != backend._ffi.NULL)
+        oid = x509.ObjectIdentifier(_obj2txt(backend, ad.method))
+        backend.openssl_assert(ad.location != backend._ffi.NULL)
+        gn = _decode_general_name(backend, ad.location)
+        access_descriptions.append(x509.AccessDescription(oid, gn))
+
+    return x509.AuthorityInformationAccess(access_descriptions)
+
+
+def _decode_key_usage(backend, bit_string):
+    bit_string = backend._ffi.cast("ASN1_BIT_STRING *", bit_string)
+    bit_string = backend._ffi.gc(bit_string, backend._lib.ASN1_BIT_STRING_free)
+    get_bit = backend._lib.ASN1_BIT_STRING_get_bit
+    digital_signature = get_bit(bit_string, 0) == 1
+    content_commitment = get_bit(bit_string, 1) == 1
+    key_encipherment = get_bit(bit_string, 2) == 1
+    data_encipherment = get_bit(bit_string, 3) == 1
+    key_agreement = get_bit(bit_string, 4) == 1
+    key_cert_sign = get_bit(bit_string, 5) == 1
+    crl_sign = get_bit(bit_string, 6) == 1
+    encipher_only = get_bit(bit_string, 7) == 1
+    decipher_only = get_bit(bit_string, 8) == 1
+    return x509.KeyUsage(
+        digital_signature,
+        content_commitment,
+        key_encipherment,
+        data_encipherment,
+        key_agreement,
+        key_cert_sign,
+        crl_sign,
+        encipher_only,
+        decipher_only
+    )
+
+
+def _decode_general_names_extension(backend, gns):
+    gns = backend._ffi.cast("GENERAL_NAMES *", gns)
+    gns = backend._ffi.gc(gns, backend._lib.GENERAL_NAMES_free)
+    general_names = _decode_general_names(backend, gns)
+    return general_names
+
+
+def _decode_subject_alt_name(backend, ext):
+    return x509.SubjectAlternativeName(
+        _decode_general_names_extension(backend, ext)
+    )
+
+
+def _decode_issuer_alt_name(backend, ext):
+    return x509.IssuerAlternativeName(
+        _decode_general_names_extension(backend, ext)
+    )
+
+
+def _decode_name_constraints(backend, nc):
+    nc = backend._ffi.cast("NAME_CONSTRAINTS *", nc)
+    nc = backend._ffi.gc(nc, backend._lib.NAME_CONSTRAINTS_free)
+    permitted = _decode_general_subtrees(backend, nc.permittedSubtrees)
+    excluded = _decode_general_subtrees(backend, nc.excludedSubtrees)
+    return x509.NameConstraints(
+        permitted_subtrees=permitted, excluded_subtrees=excluded
+    )
+
+
+def _decode_general_subtrees(backend, stack_subtrees):
+    if stack_subtrees == backend._ffi.NULL:
+        return None
+
+    num = backend._lib.sk_GENERAL_SUBTREE_num(stack_subtrees)
+    subtrees = []
+
+    for i in range(num):
+        obj = backend._lib.sk_GENERAL_SUBTREE_value(stack_subtrees, i)
+        backend.openssl_assert(obj != backend._ffi.NULL)
+        name = _decode_general_name(backend, obj.base)
+        subtrees.append(name)
+
+    return subtrees
+
+
+def _decode_extended_key_usage(backend, sk):
+    sk = backend._ffi.cast("Cryptography_STACK_OF_ASN1_OBJECT *", sk)
+    sk = backend._ffi.gc(sk, backend._lib.sk_ASN1_OBJECT_free)
+    num = backend._lib.sk_ASN1_OBJECT_num(sk)
+    ekus = []
+
+    for i in range(num):
+        obj = backend._lib.sk_ASN1_OBJECT_value(sk, i)
+        backend.openssl_assert(obj != backend._ffi.NULL)
+        oid = x509.ObjectIdentifier(_obj2txt(backend, obj))
+        ekus.append(oid)
+
+    return x509.ExtendedKeyUsage(ekus)
+
+
+_DISTPOINT_TYPE_FULLNAME = 0
+_DISTPOINT_TYPE_RELATIVENAME = 1
+
+
+def _decode_crl_distribution_points(backend, cdps):
+    cdps = backend._ffi.cast("Cryptography_STACK_OF_DIST_POINT *", cdps)
+    cdps = backend._ffi.gc(cdps, backend._lib.sk_DIST_POINT_free)
+    num = backend._lib.sk_DIST_POINT_num(cdps)
+
+    dist_points = []
+    for i in range(num):
+        full_name = None
+        relative_name = None
+        crl_issuer = None
+        reasons = None
+        cdp = backend._lib.sk_DIST_POINT_value(cdps, i)
+        if cdp.reasons != backend._ffi.NULL:
+            # We will check each bit from RFC 5280
+            # ReasonFlags ::= BIT STRING {
+            #      unused                  (0),
+            #      keyCompromise           (1),
+            #      cACompromise            (2),
+            #      affiliationChanged      (3),
+            #      superseded              (4),
+            #      cessationOfOperation    (5),
+            #      certificateHold         (6),
+            #      privilegeWithdrawn      (7),
+            #      aACompromise            (8) }
+            reasons = []
+            get_bit = backend._lib.ASN1_BIT_STRING_get_bit
+            if get_bit(cdp.reasons, 1):
+                reasons.append(x509.ReasonFlags.key_compromise)
+
+            if get_bit(cdp.reasons, 2):
+                reasons.append(x509.ReasonFlags.ca_compromise)
+
+            if get_bit(cdp.reasons, 3):
+                reasons.append(x509.ReasonFlags.affiliation_changed)
+
+            if get_bit(cdp.reasons, 4):
+                reasons.append(x509.ReasonFlags.superseded)
+
+            if get_bit(cdp.reasons, 5):
+                reasons.append(x509.ReasonFlags.cessation_of_operation)
+
+            if get_bit(cdp.reasons, 6):
+                reasons.append(x509.ReasonFlags.certificate_hold)
+
+            if get_bit(cdp.reasons, 7):
+                reasons.append(x509.ReasonFlags.privilege_withdrawn)
+
+            if get_bit(cdp.reasons, 8):
+                reasons.append(x509.ReasonFlags.aa_compromise)
+
+            reasons = frozenset(reasons)
+
+        if cdp.CRLissuer != backend._ffi.NULL:
+            crl_issuer = _decode_general_names(backend, cdp.CRLissuer)
+
+        # Certificates may have a crl_issuer/reasons and no distribution
+        # point so make sure it's not null.
+        if cdp.distpoint != backend._ffi.NULL:
+            # Type 0 is fullName, there is no #define for it in the code.
+            if cdp.distpoint.type == _DISTPOINT_TYPE_FULLNAME:
+                full_name = _decode_general_names(
+                    backend, cdp.distpoint.name.fullname
+                )
+            # OpenSSL code doesn't test for a specific type for
+            # relativename, everything that isn't fullname is considered
+            # relativename.
+            else:
+                rns = cdp.distpoint.name.relativename
+                rnum = backend._lib.sk_X509_NAME_ENTRY_num(rns)
+                attributes = []
+                for i in range(rnum):
+                    rn = backend._lib.sk_X509_NAME_ENTRY_value(
+                        rns, i
+                    )
+                    backend.openssl_assert(rn != backend._ffi.NULL)
+                    attributes.append(
+                        _decode_x509_name_entry(backend, rn)
+                    )
+
+                relative_name = x509.Name(attributes)
+
+        dist_points.append(
+            x509.DistributionPoint(
+                full_name, relative_name, reasons, crl_issuer
+            )
+        )
+
+    return x509.CRLDistributionPoints(dist_points)
+
+
+def _decode_inhibit_any_policy(backend, asn1_int):
+    asn1_int = backend._ffi.cast("ASN1_INTEGER *", asn1_int)
+    asn1_int = backend._ffi.gc(asn1_int, backend._lib.ASN1_INTEGER_free)
+    skip_certs = backend._asn1_integer_to_int(asn1_int)
+    return x509.InhibitAnyPolicy(skip_certs)
+
+
+_CRL_REASON_CODE_TO_ENUM = {
+    0: x509.ReasonFlags.unspecified,
+    1: x509.ReasonFlags.key_compromise,
+    2: x509.ReasonFlags.ca_compromise,
+    3: x509.ReasonFlags.affiliation_changed,
+    4: x509.ReasonFlags.superseded,
+    5: x509.ReasonFlags.cessation_of_operation,
+    6: x509.ReasonFlags.certificate_hold,
+    8: x509.ReasonFlags.remove_from_crl,
+    9: x509.ReasonFlags.privilege_withdrawn,
+    10: x509.ReasonFlags.aa_compromise,
+}
+
+
+def _decode_crl_reason(backend, enum):
+    enum = backend._ffi.cast("ASN1_ENUMERATED *", enum)
+    enum = backend._ffi.gc(enum, backend._lib.ASN1_ENUMERATED_free)
+    code = backend._lib.ASN1_ENUMERATED_get(enum)
+
+    try:
+        return _CRL_REASON_CODE_TO_ENUM[code]
+    except KeyError:
+        raise ValueError("Unsupported reason code: {0}".format(code))
+
+
+def _decode_invalidity_date(backend, inv_date):
+    generalized_time = backend._ffi.cast(
+        "ASN1_GENERALIZEDTIME *", inv_date
+    )
+    generalized_time = backend._ffi.gc(
+        generalized_time, backend._lib.ASN1_GENERALIZEDTIME_free
+    )
+    time = backend._ffi.string(
+        backend._lib.ASN1_STRING_data(
+            backend._ffi.cast("ASN1_STRING *", generalized_time)
+        )
+    ).decode("ascii")
+    return datetime.datetime.strptime(time, "%Y%m%d%H%M%SZ")
+
+
+def _decode_cert_issuer(backend, ext):
+    """
+    This handler decodes the CertificateIssuer entry extension directly
+    from the X509_EXTENSION object. This is necessary because this entry
+    extension is not directly supported by OpenSSL 0.9.8.
+    """
+
+    data_ptr_ptr = backend._ffi.new("const unsigned char **")
+    data_ptr_ptr[0] = ext.value.data
+    gns = backend._lib.d2i_GENERAL_NAMES(
+        backend._ffi.NULL, data_ptr_ptr, ext.value.length
+    )
+
+    # Check the result of d2i_GENERAL_NAMES() is valid. Usually this is covered
+    # in _X509ExtensionParser but since we are responsible for decoding this
+    # entry extension ourselves, we have to this here.
+    if gns == backend._ffi.NULL:
+        backend._consume_errors()
+        raise ValueError(
+            "The {0} extension is corrupted and can't be parsed".format(
+                CRLExtensionOID.CERTIFICATE_ISSUER))
+
+    gns = backend._ffi.gc(gns, backend._lib.GENERAL_NAMES_free)
+    return x509.GeneralNames(_decode_general_names(backend, gns))
+
+
+@utils.register_interface(x509.RevokedCertificate)
+class _RevokedCertificate(object):
+    def __init__(self, backend, x509_revoked):
+        self._backend = backend
+        self._x509_revoked = x509_revoked
+
+    @property
+    def serial_number(self):
+        asn1_int = self._x509_revoked.serialNumber
+        self._backend.openssl_assert(asn1_int != self._backend._ffi.NULL)
+        return self._backend._asn1_integer_to_int(asn1_int)
+
+    @property
+    def revocation_date(self):
+        return self._backend._parse_asn1_time(
+            self._x509_revoked.revocationDate)
+
+    @property
+    def extensions(self):
+        return _REVOKED_CERTIFICATE_EXTENSION_PARSER.parse(
+            self._backend, self._x509_revoked
+        )
+
+
+@utils.register_interface(x509.CertificateRevocationList)
+class _CertificateRevocationList(object):
+    def __init__(self, backend, x509_crl):
+        self._backend = backend
+        self._x509_crl = x509_crl
+
+    def __eq__(self, other):
+        if not isinstance(other, x509.CertificateRevocationList):
+            return NotImplemented
+
+        res = self._backend._lib.X509_CRL_cmp(self._x509_crl, other._x509_crl)
+        return res == 0
+
+    def __ne__(self, other):
+        return not self == other
+
+    def fingerprint(self, algorithm):
+        h = hashes.Hash(algorithm, self._backend)
+        bio = self._backend._create_mem_bio()
+        res = self._backend._lib.i2d_X509_CRL_bio(
+            bio, self._x509_crl
+        )
+        self._backend.openssl_assert(res == 1)
+        der = self._backend._read_mem_bio(bio)
+        h.update(der)
+        return h.finalize()
+
+    @property
+    def signature_hash_algorithm(self):
+        oid = _obj2txt(self._backend, self._x509_crl.sig_alg.algorithm)
+        try:
+            return x509._SIG_OIDS_TO_HASH[oid]
+        except KeyError:
+            raise UnsupportedAlgorithm(
+                "Signature algorithm OID:{0} not recognized".format(oid)
+            )
+
+    @property
+    def issuer(self):
+        issuer = self._backend._lib.X509_CRL_get_issuer(self._x509_crl)
+        self._backend.openssl_assert(issuer != self._backend._ffi.NULL)
+        return _decode_x509_name(self._backend, issuer)
+
+    @property
+    def next_update(self):
+        nu = self._backend._lib.X509_CRL_get_nextUpdate(self._x509_crl)
+        self._backend.openssl_assert(nu != self._backend._ffi.NULL)
+        return self._backend._parse_asn1_time(nu)
+
+    @property
+    def last_update(self):
+        lu = self._backend._lib.X509_CRL_get_lastUpdate(self._x509_crl)
+        self._backend.openssl_assert(lu != self._backend._ffi.NULL)
+        return self._backend._parse_asn1_time(lu)
+
+    def _revoked_certificates(self):
+        revoked = self._backend._lib.X509_CRL_get_REVOKED(self._x509_crl)
+        self._backend.openssl_assert(revoked != self._backend._ffi.NULL)
+
+        num = self._backend._lib.sk_X509_REVOKED_num(revoked)
+        revoked_list = []
+        for i in range(num):
+            r = self._backend._lib.sk_X509_REVOKED_value(revoked, i)
+            self._backend.openssl_assert(r != self._backend._ffi.NULL)
+            revoked_list.append(_RevokedCertificate(self._backend, r))
+
+        return revoked_list
+
+    def __iter__(self):
+        return iter(self._revoked_certificates())
+
+    def __getitem__(self, idx):
+        return self._revoked_certificates()[idx]
+
+    def __len__(self):
+        return len(self._revoked_certificates())
+
+    @property
+    def extensions(self):
+        raise NotImplementedError()
+
+
+@utils.register_interface(x509.CertificateSigningRequest)
+class _CertificateSigningRequest(object):
+    def __init__(self, backend, x509_req):
+        self._backend = backend
+        self._x509_req = x509_req
+
+    def __eq__(self, other):
+        if not isinstance(other, _CertificateSigningRequest):
+            return NotImplemented
+
+        self_bytes = self.public_bytes(serialization.Encoding.DER)
+        other_bytes = other.public_bytes(serialization.Encoding.DER)
+        return self_bytes == other_bytes
+
+    def __ne__(self, other):
+        return not self == other
+
+    def __hash__(self):
+        return hash(self.public_bytes(serialization.Encoding.DER))
+
+    def public_key(self):
+        pkey = self._backend._lib.X509_REQ_get_pubkey(self._x509_req)
+        self._backend.openssl_assert(pkey != self._backend._ffi.NULL)
+        pkey = self._backend._ffi.gc(pkey, self._backend._lib.EVP_PKEY_free)
+        return self._backend._evp_pkey_to_public_key(pkey)
+
+    @property
+    def subject(self):
+        subject = self._backend._lib.X509_REQ_get_subject_name(self._x509_req)
+        self._backend.openssl_assert(subject != self._backend._ffi.NULL)
+        return _decode_x509_name(self._backend, subject)
+
+    @property
+    def signature_hash_algorithm(self):
+        oid = _obj2txt(self._backend, self._x509_req.sig_alg.algorithm)
+        try:
+            return x509._SIG_OIDS_TO_HASH[oid]
+        except KeyError:
+            raise UnsupportedAlgorithm(
+                "Signature algorithm OID:{0} not recognized".format(oid)
+            )
+
+    @property
+    def extensions(self):
+        x509_exts = self._backend._lib.X509_REQ_get_extensions(self._x509_req)
+        return _CSR_EXTENSION_PARSER.parse(self._backend, x509_exts)
+
+    def public_bytes(self, encoding):
+        bio = self._backend._create_mem_bio()
+        if encoding is serialization.Encoding.PEM:
+            res = self._backend._lib.PEM_write_bio_X509_REQ(
+                bio, self._x509_req
+            )
+        elif encoding is serialization.Encoding.DER:
+            res = self._backend._lib.i2d_X509_REQ_bio(bio, self._x509_req)
+        else:
+            raise TypeError("encoding must be an item from the Encoding enum")
+
+        self._backend.openssl_assert(res == 1)
+        return self._backend._read_mem_bio(bio)
+
+
+_EXTENSION_HANDLERS = {
+    ExtensionOID.BASIC_CONSTRAINTS: _decode_basic_constraints,
+    ExtensionOID.SUBJECT_KEY_IDENTIFIER: _decode_subject_key_identifier,
+    ExtensionOID.KEY_USAGE: _decode_key_usage,
+    ExtensionOID.SUBJECT_ALTERNATIVE_NAME: _decode_subject_alt_name,
+    ExtensionOID.EXTENDED_KEY_USAGE: _decode_extended_key_usage,
+    ExtensionOID.AUTHORITY_KEY_IDENTIFIER: _decode_authority_key_identifier,
+    ExtensionOID.AUTHORITY_INFORMATION_ACCESS: (
+        _decode_authority_information_access
+    ),
+    ExtensionOID.CERTIFICATE_POLICIES: _decode_certificate_policies,
+    ExtensionOID.CRL_DISTRIBUTION_POINTS: _decode_crl_distribution_points,
+    ExtensionOID.OCSP_NO_CHECK: _decode_ocsp_no_check,
+    ExtensionOID.INHIBIT_ANY_POLICY: _decode_inhibit_any_policy,
+    ExtensionOID.ISSUER_ALTERNATIVE_NAME: _decode_issuer_alt_name,
+    ExtensionOID.NAME_CONSTRAINTS: _decode_name_constraints,
+}
+
+_REVOKED_EXTENSION_HANDLERS = {
+    CRLExtensionOID.CRL_REASON: _decode_crl_reason,
+    CRLExtensionOID.INVALIDITY_DATE: _decode_invalidity_date,
+    CRLExtensionOID.CERTIFICATE_ISSUER: _decode_cert_issuer,
+}
+
+_REVOKED_UNSUPPORTED_EXTENSIONS = set([
+    CRLExtensionOID.CERTIFICATE_ISSUER,
+])
+
+_CERTIFICATE_EXTENSION_PARSER = _X509ExtensionParser(
+    ext_count=lambda backend, x: backend._lib.X509_get_ext_count(x),
+    get_ext=lambda backend, x, i: backend._lib.X509_get_ext(x, i),
+    handlers=_EXTENSION_HANDLERS
+)
+
+_CSR_EXTENSION_PARSER = _X509ExtensionParser(
+    ext_count=lambda backend, x: backend._lib.sk_X509_EXTENSION_num(x),
+    get_ext=lambda backend, x, i: backend._lib.sk_X509_EXTENSION_value(x, i),
+    handlers=_EXTENSION_HANDLERS
+)
+
+_REVOKED_CERTIFICATE_EXTENSION_PARSER = _X509ExtensionParser(
+    ext_count=lambda backend, x: backend._lib.X509_REVOKED_get_ext_count(x),
+    get_ext=lambda backend, x, i: backend._lib.X509_REVOKED_get_ext(x, i),
+    handlers=_REVOKED_EXTENSION_HANDLERS,
+    unsupported_exts=_REVOKED_UNSUPPORTED_EXTENSIONS
+)

lib/python3.5/site-packages/cryptography/hazmat/bindings/__init__.py

@@ -0,0 +1,5 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function

lib/python3.5/site-packages/cryptography/hazmat/bindings/commoncrypto/__init__.py

@@ -0,0 +1,5 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function

lib/python3.5/site-packages/cryptography/hazmat/bindings/commoncrypto/binding.py

@@ -0,0 +1,15 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+from cryptography.hazmat.bindings._commoncrypto import ffi, lib
+
+
+class Binding(object):
+    """
+    CommonCrypto API wrapper.
+    """
+    lib = lib
+    ffi = ffi

lib/python3.5/site-packages/cryptography/hazmat/bindings/openssl/__init__.py

@@ -0,0 +1,5 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function

lib/python3.5/site-packages/cryptography/hazmat/bindings/openssl/_conditional.py

@@ -0,0 +1,423 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+# This is a temporary copy of all the CONDITIONAL_NAMES from _cffi_src so
+# we can loop over them and delete them at runtime. It will be removed when
+# cffi supports #if in cdef
+
+CONDITIONAL_NAMES = {
+    "Cryptography_HAS_AES_WRAP": [
+        "AES_wrap_key",
+        "AES_unwrap_key",
+    ],
+    "Cryptography_HAS_CMAC": [
+        "CMAC_CTX_new",
+        "CMAC_Init",
+        "CMAC_Update",
+        "CMAC_Final",
+        "CMAC_CTX_copy",
+        "CMAC_CTX_free",
+    ],
+    "Cryptography_HAS_CMS": [
+        "BIO_new_CMS",
+        "i2d_CMS_bio_stream",
+        "PEM_write_bio_CMS_stream",
+        "CMS_final",
+        "CMS_sign",
+        "CMS_verify",
+        "CMS_encrypt",
+        "CMS_decrypt",
+        "CMS_add1_signer",
+        "CMS_TEXT",
+        "CMS_NOCERTS",
+        "CMS_NO_CONTENT_VERIFY",
+        "CMS_NO_ATTR_VERIFY",
+        "CMS_NOSIGS",
+        "CMS_NOINTERN",
+        "CMS_NO_SIGNER_CERT_VERIFY",
+        "CMS_NOVERIFY",
+        "CMS_DETACHED",
+        "CMS_BINARY",
+        "CMS_NOATTR",
+        "CMS_NOSMIMECAP",
+        "CMS_NOOLDMIMETYPE",
+        "CMS_CRLFEOL",
+        "CMS_STREAM",
+        "CMS_NOCRL",
+        "CMS_PARTIAL",
+        "CMS_REUSE_DIGEST",
+        "CMS_USE_KEYID",
+        "CMS_DEBUG_DECRYPT",
+    ],
+    "Cryptography_HAS_CMS_BIO_FUNCTIONS": [
+        "BIO_new_CMS",
+        "i2d_CMS_bio_stream",
+        "PEM_write_bio_CMS_stream",
+    ],
+    "Cryptography_HAS_EC": [
+        "OPENSSL_EC_NAMED_CURVE",
+        "EC_GROUP_new",
+        "EC_GROUP_free",
+        "EC_GROUP_clear_free",
+        "EC_GROUP_new_curve_GFp",
+        "EC_GROUP_new_by_curve_name",
+        "EC_GROUP_set_curve_GFp",
+        "EC_GROUP_get_curve_GFp",
+        "EC_GROUP_method_of",
+        "EC_GROUP_get0_generator",
+        "EC_GROUP_get_curve_name",
+        "EC_GROUP_get_degree",
+        "EC_GROUP_set_asn1_flag",
+        "EC_GROUP_set_point_conversion_form",
+        "EC_KEY_new",
+        "EC_KEY_free",
+        "EC_get_builtin_curves",
+        "EC_KEY_new_by_curve_name",
+        "EC_KEY_copy",
+        "EC_KEY_dup",
+        "EC_KEY_up_ref",
+        "EC_KEY_set_group",
+        "EC_KEY_get0_private_key",
+        "EC_KEY_set_private_key",
+        "EC_KEY_set_public_key",
+        "EC_KEY_get_enc_flags",
+        "EC_KEY_set_enc_flags",
+        "EC_KEY_set_conv_form",
+        "EC_KEY_get_key_method_data",
+        "EC_KEY_insert_key_method_data",
+        "EC_KEY_set_asn1_flag",
+        "EC_KEY_precompute_mult",
+        "EC_KEY_generate_key",
+        "EC_KEY_check_key",
+        "EC_POINT_new",
+        "EC_POINT_free",
+        "EC_POINT_clear_free",
+        "EC_POINT_copy",
+        "EC_POINT_dup",
+        "EC_POINT_method_of",
+        "EC_POINT_set_to_infinity",
+        "EC_POINT_set_Jprojective_coordinates_GFp",
+        "EC_POINT_get_Jprojective_coordinates_GFp",
+        "EC_POINT_set_affine_coordinates_GFp",
+        "EC_POINT_get_affine_coordinates_GFp",
+        "EC_POINT_set_compressed_coordinates_GFp",
+        "EC_POINT_point2oct",
+        "EC_POINT_oct2point",
+        "EC_POINT_point2bn",
+        "EC_POINT_bn2point",
+        "EC_POINT_point2hex",
+        "EC_POINT_hex2point",
+        "EC_POINT_add",
+        "EC_POINT_dbl",
+        "EC_POINT_invert",
+        "EC_POINT_is_at_infinity",
+        "EC_POINT_is_on_curve",
+        "EC_POINT_cmp",
+        "EC_POINT_make_affine",
+        "EC_POINTs_make_affine",
+        "EC_POINTs_mul",
+        "EC_POINT_mul",
+        "EC_GROUP_precompute_mult",
+        "EC_GROUP_have_precompute_mult",
+        "EC_GFp_simple_method",
+        "EC_GFp_mont_method",
+        "EC_GFp_nist_method",
+        "EC_METHOD_get_field_type",
+        "EVP_PKEY_assign_EC_KEY",
+        "EVP_PKEY_get1_EC_KEY",
+        "EVP_PKEY_set1_EC_KEY",
+        "PEM_write_bio_ECPrivateKey",
+        "i2d_EC_PUBKEY",
+        "d2i_EC_PUBKEY",
+        "d2i_EC_PUBKEY_bio",
+        "i2d_EC_PUBKEY_bio",
+        "d2i_ECPrivateKey",
+        "d2i_ECPrivateKey_bio",
+        "i2d_ECPrivateKey",
+        "i2d_ECPrivateKey_bio",
+        "i2o_ECPublicKey",
+        "o2i_ECPublicKey",
+        "SSL_CTX_set_tmp_ecdh",
+    ],
+
+    "Cryptography_HAS_EC_1_0_1": [
+        "EC_KEY_get_flags",
+        "EC_KEY_set_flags",
+        "EC_KEY_clear_flags",
+        "EC_KEY_set_public_key_affine_coordinates",
+    ],
+
+    "Cryptography_HAS_EC_NISTP_64_GCC_128": [
+        "EC_GFp_nistp224_method",
+        "EC_GFp_nistp256_method",
+        "EC_GFp_nistp521_method",
+    ],
+
+    "Cryptography_HAS_EC2M": [
+        "EC_GF2m_simple_method",
+        "EC_POINT_set_affine_coordinates_GF2m",
+        "EC_POINT_get_affine_coordinates_GF2m",
+        "EC_POINT_set_compressed_coordinates_GF2m",
+        "EC_GROUP_set_curve_GF2m",
+        "EC_GROUP_get_curve_GF2m",
+        "EC_GROUP_new_curve_GF2m",
+    ],
+
+    "Cryptography_HAS_EC_1_0_2": [
+        "EC_curve_nid2nist",
+    ],
+    "Cryptography_HAS_ECDH": [
+        "ECDH_compute_key",
+        "ECDH_get_ex_new_index",
+        "ECDH_set_ex_data",
+        "ECDH_get_ex_data",
+    ],
+    "Cryptography_HAS_ECDSA": [
+        "ECDSA_SIG_new",
+        "ECDSA_SIG_free",
+        "i2d_ECDSA_SIG",
+        "d2i_ECDSA_SIG",
+        "ECDSA_do_sign",
+        "ECDSA_do_sign_ex",
+        "ECDSA_do_verify",
+        "ECDSA_sign_setup",
+        "ECDSA_sign",
+        "ECDSA_sign_ex",
+        "ECDSA_verify",
+        "ECDSA_size",
+        "ECDSA_OpenSSL",
+        "ECDSA_set_default_method",
+        "ECDSA_get_default_method",
+        "ECDSA_set_method",
+        "ECDSA_get_ex_new_index",
+        "ECDSA_set_ex_data",
+        "ECDSA_get_ex_data",
+    ],
+    "Cryptography_HAS_ENGINE_CRYPTODEV": [
+        "ENGINE_load_cryptodev"
+    ],
+    "Cryptography_HAS_REMOVE_THREAD_STATE": [
+        "ERR_remove_thread_state"
+    ],
+    "Cryptography_HAS_098H_ERROR_CODES": [
+        "ASN1_F_B64_READ_ASN1",
+        "ASN1_F_B64_WRITE_ASN1",
+        "ASN1_F_SMIME_READ_ASN1",
+        "ASN1_F_SMIME_TEXT",
+        "ASN1_R_NO_CONTENT_TYPE",
+        "ASN1_R_NO_MULTIPART_BODY_FAILURE",
+        "ASN1_R_NO_MULTIPART_BOUNDARY",
+    ],
+    "Cryptography_HAS_098C_CAMELLIA_CODES": [
+        "EVP_F_CAMELLIA_INIT_KEY",
+        "EVP_R_CAMELLIA_KEY_SETUP_FAILED"
+    ],
+    "Cryptography_HAS_EC_CODES": [
+        "EC_R_UNKNOWN_GROUP",
+        "EC_F_EC_GROUP_NEW_BY_CURVE_NAME"
+    ],
+    "Cryptography_HAS_RSA_R_PKCS_DECODING_ERROR": [
+        "RSA_R_PKCS_DECODING_ERROR"
+    ],
+    "Cryptography_HAS_GCM": [
+        "EVP_CTRL_GCM_GET_TAG",
+        "EVP_CTRL_GCM_SET_TAG",
+        "EVP_CTRL_GCM_SET_IVLEN",
+    ],
+    "Cryptography_HAS_PBKDF2_HMAC": [
+        "PKCS5_PBKDF2_HMAC"
+    ],
+    "Cryptography_HAS_PKEY_CTX": [
+        "EVP_PKEY_CTX_new",
+        "EVP_PKEY_CTX_new_id",
+        "EVP_PKEY_CTX_dup",
+        "EVP_PKEY_CTX_free",
+        "EVP_PKEY_sign",
+        "EVP_PKEY_sign_init",
+        "EVP_PKEY_verify",
+        "EVP_PKEY_verify_init",
+        "Cryptography_EVP_PKEY_encrypt",
+        "EVP_PKEY_encrypt_init",
+        "Cryptography_EVP_PKEY_decrypt",
+        "EVP_PKEY_decrypt_init",
+        "EVP_PKEY_CTX_set_signature_md",
+        "EVP_PKEY_id",
+        "EVP_PKEY_CTX_set_rsa_padding",
+        "EVP_PKEY_CTX_set_rsa_pss_saltlen",
+    ],
+    "Cryptography_HAS_ECDSA_SHA2_NIDS": [
+        "NID_ecdsa_with_SHA224",
+        "NID_ecdsa_with_SHA256",
+        "NID_ecdsa_with_SHA384",
+        "NID_ecdsa_with_SHA512",
+    ],
+    "Cryptography_HAS_EGD": [
+        "RAND_egd",
+        "RAND_egd_bytes",
+        "RAND_query_egd_bytes",
+    ],
+    "Cryptography_HAS_PSS_PADDING": [
+        "RSA_PKCS1_PSS_PADDING",
+    ],
+    "Cryptography_HAS_MGF1_MD": [
+        "EVP_PKEY_CTX_set_rsa_mgf1_md",
+    ],
+    "Cryptography_HAS_TLSv1_1": [
+        "SSL_OP_NO_TLSv1_1",
+        "TLSv1_1_method",
+        "TLSv1_1_server_method",
+        "TLSv1_1_client_method",
+    ],
+
+    "Cryptography_HAS_TLSv1_2": [
+        "SSL_OP_NO_TLSv1_2",
+        "TLSv1_2_method",
+        "TLSv1_2_server_method",
+        "TLSv1_2_client_method",
+    ],
+
+    "Cryptography_HAS_SSL2": [
+        "SSLv2_method",
+        "SSLv2_client_method",
+        "SSLv2_server_method",
+    ],
+
+    "Cryptography_HAS_SSL3_METHOD": [
+        "SSLv3_method",
+        "SSLv3_client_method",
+        "SSLv3_server_method",
+    ],
+
+    "Cryptography_HAS_TLSEXT_HOSTNAME": [
+        "SSL_set_tlsext_host_name",
+        "SSL_get_servername",
+        "SSL_CTX_set_tlsext_servername_callback",
+    ],
+
+    "Cryptography_HAS_TLSEXT_STATUS_REQ_CB": [
+        "SSL_CTX_set_tlsext_status_cb",
+        "SSL_CTX_set_tlsext_status_arg"
+    ],
+
+    "Cryptography_HAS_STATUS_REQ_OCSP_RESP": [
+        "SSL_set_tlsext_status_ocsp_resp",
+        "SSL_get_tlsext_status_ocsp_resp",
+    ],
+
+    "Cryptography_HAS_TLSEXT_STATUS_REQ_TYPE": [
+        "SSL_set_tlsext_status_type",
+    ],
+
+    "Cryptography_HAS_RELEASE_BUFFERS": [
+        "SSL_MODE_RELEASE_BUFFERS",
+    ],
+
+    "Cryptography_HAS_OP_NO_COMPRESSION": [
+        "SSL_OP_NO_COMPRESSION",
+    ],
+
+    "Cryptography_HAS_SSL_OP_MSIE_SSLV2_RSA_PADDING": [
+        "SSL_OP_MSIE_SSLV2_RSA_PADDING",
+    ],
+
+    "Cryptography_HAS_SSL_OP_NO_TICKET": [
+        "SSL_OP_NO_TICKET",
+    ],
+
+    "Cryptography_HAS_SSL_SET_SSL_CTX": [
+        "SSL_set_SSL_CTX",
+        "TLSEXT_NAMETYPE_host_name",
+    ],
+
+    "Cryptography_HAS_NETBSD_D1_METH": [
+        "DTLSv1_method",
+    ],
+
+    "Cryptography_HAS_NEXTPROTONEG": [
+        "SSL_CTX_set_next_protos_advertised_cb",
+        "SSL_CTX_set_next_proto_select_cb",
+        "SSL_select_next_proto",
+        "SSL_get0_next_proto_negotiated",
+    ],
+
+    "Cryptography_HAS_SECURE_RENEGOTIATION": [
+        "SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION",
+        "SSL_OP_LEGACY_SERVER_CONNECT",
+        "SSL_get_secure_renegotiation_support",
+    ],
+
+    "Cryptography_HAS_ALPN": [
+        "SSL_CTX_set_alpn_protos",
+        "SSL_set_alpn_protos",
+        "SSL_CTX_set_alpn_select_cb",
+        "SSL_get0_alpn_selected",
+    ],
+
+    "Cryptography_HAS_COMPRESSION": [
+        "SSL_get_current_compression",
+        "SSL_get_current_expansion",
+        "SSL_COMP_get_name",
+    ],
+
+    "Cryptography_HAS_GET_SERVER_TMP_KEY": [
+        "SSL_get_server_tmp_key",
+    ],
+
+    "Cryptography_HAS_SSL_CTX_SET_CLIENT_CERT_ENGINE": [
+        "SSL_CTX_set_client_cert_engine",
+    ],
+    "Cryptography_HAS_102_VERIFICATION_ERROR_CODES": [
+        'X509_V_ERR_SUITE_B_INVALID_VERSION',
+        'X509_V_ERR_SUITE_B_INVALID_ALGORITHM',
+        'X509_V_ERR_SUITE_B_INVALID_CURVE',
+        'X509_V_ERR_SUITE_B_INVALID_SIGNATURE_ALGORITHM',
+        'X509_V_ERR_SUITE_B_LOS_NOT_ALLOWED',
+        'X509_V_ERR_SUITE_B_CANNOT_SIGN_P_384_WITH_P_256',
+        'X509_V_ERR_HOSTNAME_MISMATCH',
+        'X509_V_ERR_EMAIL_MISMATCH',
+        'X509_V_ERR_IP_ADDRESS_MISMATCH'
+    ],
+    "Cryptography_HAS_102_VERIFICATION_PARAMS": [
+        "X509_V_FLAG_SUITEB_128_LOS_ONLY",
+        "X509_V_FLAG_SUITEB_192_LOS",
+        "X509_V_FLAG_SUITEB_128_LOS",
+        "X509_VERIFY_PARAM_set1_host",
+        "X509_VERIFY_PARAM_set1_email",
+        "X509_VERIFY_PARAM_set1_ip",
+        "X509_VERIFY_PARAM_set1_ip_asc",
+        "X509_VERIFY_PARAM_set_hostflags",
+    ],
+    "Cryptography_HAS_X509_V_FLAG_TRUSTED_FIRST": [
+        "X509_V_FLAG_TRUSTED_FIRST",
+    ],
+    "Cryptography_HAS_X509_V_FLAG_PARTIAL_CHAIN": [
+        "X509_V_FLAG_PARTIAL_CHAIN",
+    ],
+    "Cryptography_HAS_100_VERIFICATION_ERROR_CODES": [
+        'X509_V_ERR_DIFFERENT_CRL_SCOPE',
+        'X509_V_ERR_UNSUPPORTED_EXTENSION_FEATURE',
+        'X509_V_ERR_UNNESTED_RESOURCE',
+        'X509_V_ERR_PERMITTED_VIOLATION',
+        'X509_V_ERR_EXCLUDED_VIOLATION',
+        'X509_V_ERR_SUBTREE_MINMAX',
+        'X509_V_ERR_UNSUPPORTED_CONSTRAINT_TYPE',
+        'X509_V_ERR_UNSUPPORTED_CONSTRAINT_SYNTAX',
+        'X509_V_ERR_UNSUPPORTED_NAME_SYNTAX',
+        'X509_V_ERR_CRL_PATH_VALIDATION_ERROR',
+    ],
+    "Cryptography_HAS_100_VERIFICATION_PARAMS": [
+        "Cryptography_HAS_100_VERIFICATION_PARAMS",
+        "X509_V_FLAG_EXTENDED_CRL_SUPPORT",
+        "X509_V_FLAG_USE_DELTAS",
+    ],
+    "Cryptography_HAS_X509_V_FLAG_CHECK_SS_SIGNATURE": [
+        "X509_V_FLAG_CHECK_SS_SIGNATURE",
+    ],
+    "Cryptography_HAS_SET_CERT_CB": [
+        "SSL_CTX_set_cert_cb",
+        "SSL_set_cert_cb",
+    ],
+}

lib/python3.5/site-packages/cryptography/hazmat/bindings/openssl/binding.py

@@ -0,0 +1,182 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import collections
+import os
+import threading
+import types
+
+from cryptography.exceptions import InternalError
+from cryptography.hazmat.bindings._openssl import ffi, lib
+from cryptography.hazmat.bindings.openssl._conditional import CONDITIONAL_NAMES
+
+
+_OpenSSLError = collections.namedtuple("_OpenSSLError",
+                                       ["code", "lib", "func", "reason"])
+
+
+def _consume_errors(lib):
+    errors = []
+    while True:
+        code = lib.ERR_get_error()
+        if code == 0:
+            break
+
+        err_lib = lib.ERR_GET_LIB(code)
+        err_func = lib.ERR_GET_FUNC(code)
+        err_reason = lib.ERR_GET_REASON(code)
+
+        errors.append(_OpenSSLError(code, err_lib, err_func, err_reason))
+    return errors
+
+
+def _openssl_assert(lib, ok):
+    if not ok:
+        errors = _consume_errors(lib)
+        raise InternalError(
+            "Unknown OpenSSL error. Please file an issue at https://github.com"
+            "/pyca/cryptography/issues with information on how to reproduce "
+            "this. ({0!r})".format(errors),
+            errors
+        )
+
+
+@ffi.callback("int (*)(unsigned char *, int)", error=-1)
+def _osrandom_rand_bytes(buf, size):
+    signed = ffi.cast("char *", buf)
+    result = os.urandom(size)
+    signed[0:size] = result
+    return 1
+
+
+@ffi.callback("int (*)(void)")
+def _osrandom_rand_status():
+    return 1
+
+
+def build_conditional_library(lib, conditional_names):
+    conditional_lib = types.ModuleType("lib")
+    excluded_names = set()
+    for condition, names in conditional_names.items():
+        if not getattr(lib, condition):
+            excluded_names |= set(names)
+
+    for attr in dir(lib):
+        if attr not in excluded_names:
+            setattr(conditional_lib, attr, getattr(lib, attr))
+
+    return conditional_lib
+
+
+class Binding(object):
+    """
+    OpenSSL API wrapper.
+    """
+    lib = None
+    ffi = ffi
+    _lib_loaded = False
+    _locks = None
+    _lock_cb_handle = None
+    _init_lock = threading.Lock()
+    _lock_init_lock = threading.Lock()
+
+    _osrandom_engine_id = ffi.new("const char[]", b"osrandom")
+    _osrandom_engine_name = ffi.new("const char[]", b"osrandom_engine")
+    _osrandom_method = ffi.new(
+        "RAND_METHOD *",
+        dict(bytes=_osrandom_rand_bytes, pseudorand=_osrandom_rand_bytes,
+             status=_osrandom_rand_status)
+    )
+
+    def __init__(self):
+        self._ensure_ffi_initialized()
+
+    @classmethod
+    def _register_osrandom_engine(cls):
+        _openssl_assert(cls.lib, cls.lib.ERR_peek_error() == 0)
+
+        engine = cls.lib.ENGINE_new()
+        _openssl_assert(cls.lib, engine != cls.ffi.NULL)
+        try:
+            result = cls.lib.ENGINE_set_id(engine, cls._osrandom_engine_id)
+            _openssl_assert(cls.lib, result == 1)
+            result = cls.lib.ENGINE_set_name(engine, cls._osrandom_engine_name)
+            _openssl_assert(cls.lib, result == 1)
+            result = cls.lib.ENGINE_set_RAND(engine, cls._osrandom_method)
+            _openssl_assert(cls.lib, result == 1)
+            result = cls.lib.ENGINE_add(engine)
+            if result != 1:
+                errors = _consume_errors(cls.lib)
+                _openssl_assert(
+                    cls.lib,
+                    errors[0].reason == cls.lib.ENGINE_R_CONFLICTING_ENGINE_ID
+                )
+
+        finally:
+            result = cls.lib.ENGINE_free(engine)
+            _openssl_assert(cls.lib, result == 1)
+
+    @classmethod
+    def _ensure_ffi_initialized(cls):
+        with cls._init_lock:
+            if not cls._lib_loaded:
+                cls.lib = build_conditional_library(lib, CONDITIONAL_NAMES)
+                cls._lib_loaded = True
+                # initialize the SSL library
+                cls.lib.SSL_library_init()
+                # adds all ciphers/digests for EVP
+                cls.lib.OpenSSL_add_all_algorithms()
+                # loads error strings for libcrypto and libssl functions
+                cls.lib.SSL_load_error_strings()
+                cls._register_osrandom_engine()
+
+    @classmethod
+    def init_static_locks(cls):
+        with cls._lock_init_lock:
+            cls._ensure_ffi_initialized()
+
+            if not cls._lock_cb_handle:
+                cls._lock_cb_handle = cls.ffi.callback(
+                    "void(int, int, const char *, int)",
+                    cls._lock_cb
+                )
+
+            # Use Python's implementation if available, importing _ssl triggers
+            # the setup for this.
+            __import__("_ssl")
+
+            if cls.lib.CRYPTO_get_locking_callback() != cls.ffi.NULL:
+                return
+
+            # If nothing else has setup a locking callback already, we set up
+            # our own
+            num_locks = cls.lib.CRYPTO_num_locks()
+            cls._locks = [threading.Lock() for n in range(num_locks)]
+
+            cls.lib.CRYPTO_set_locking_callback(cls._lock_cb_handle)
+
+    @classmethod
+    def _lock_cb(cls, mode, n, file, line):
+        lock = cls._locks[n]
+
+        if mode & cls.lib.CRYPTO_LOCK:
+            lock.acquire()
+        elif mode & cls.lib.CRYPTO_UNLOCK:
+            lock.release()
+        else:
+            raise RuntimeError(
+                "Unknown lock mode {0}: lock={1}, file={2}, line={3}.".format(
+                    mode, n, file, line
+                )
+            )
+
+
+# OpenSSL is not thread safe until the locks are initialized. We call this
+# method in module scope so that it executes with the import lock. On
+# Pythons < 3.4 this import lock is a global lock, which can prevent a race
+# condition registering the OpenSSL locks. On Python 3.4+ the import lock
+# is per module so this approach will not work.
+Binding.init_static_locks()

lib/python3.5/site-packages/cryptography/hazmat/primitives/__init__.py

@@ -0,0 +1,5 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function

lib/python3.5/site-packages/cryptography/hazmat/primitives/asymmetric/__init__.py

@@ -0,0 +1,40 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import abc
+
+import six
+
+
+@six.add_metaclass(abc.ABCMeta)
+class AsymmetricSignatureContext(object):
+    @abc.abstractmethod
+    def update(self, data):
+        """
+        Processes the provided bytes and returns nothing.
+        """
+
+    @abc.abstractmethod
+    def finalize(self):
+        """
+        Returns the signature as bytes.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class AsymmetricVerificationContext(object):
+    @abc.abstractmethod
+    def update(self, data):
+        """
+        Processes the provided bytes and returns nothing.
+        """
+
+    @abc.abstractmethod
+    def verify(self):
+        """
+        Raises an exception if the bytes provided to update do not match the
+        signature or the signature does not match the public key.
+        """

lib/python3.5/site-packages/cryptography/hazmat/primitives/asymmetric/dh.py

@@ -0,0 +1,166 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import abc
+
+import six
+
+from cryptography import utils
+
+
+class DHPrivateNumbers(object):
+    def __init__(self, x, public_numbers):
+        if not isinstance(x, six.integer_types):
+            raise TypeError("x must be an integer.")
+
+        if not isinstance(public_numbers, DHPublicNumbers):
+            raise TypeError("public_numbers must be an instance of "
+                            "DHPublicNumbers.")
+
+        self._x = x
+        self._public_numbers = public_numbers
+
+    def __eq__(self, other):
+        if not isinstance(other, DHPrivateNumbers):
+            return NotImplemented
+
+        return (
+            self._x == other._x and
+            self._public_numbers == other._public_numbers
+        )
+
+    def __ne__(self, other):
+        return not self == other
+
+    public_numbers = utils.read_only_property("_public_numbers")
+    x = utils.read_only_property("_x")
+
+
+class DHPublicNumbers(object):
+    def __init__(self, y, parameter_numbers):
+        if not isinstance(y, six.integer_types):
+            raise TypeError("y must be an integer.")
+
+        if not isinstance(parameter_numbers, DHParameterNumbers):
+            raise TypeError(
+                "parameters must be an instance of DHParameterNumbers.")
+
+        self._y = y
+        self._parameter_numbers = parameter_numbers
+
+    def __eq__(self, other):
+        if not isinstance(other, DHPublicNumbers):
+            return NotImplemented
+
+        return (
+            self._y == other._y and
+            self._parameter_numbers == other._parameter_numbers
+        )
+
+    def __ne__(self, other):
+        return not self == other
+
+    y = utils.read_only_property("_y")
+    parameter_numbers = utils.read_only_property("_parameter_numbers")
+
+
+class DHParameterNumbers(object):
+    def __init__(self, p, g):
+        if (
+            not isinstance(p, six.integer_types) or
+            not isinstance(g, six.integer_types)
+        ):
+            raise TypeError("p and g must be integers")
+
+        self._p = p
+        self._g = g
+
+    def __eq__(self, other):
+        if not isinstance(other, DHParameterNumbers):
+            return NotImplemented
+
+        return (
+            self._p == other._p and
+            self._g == other._g
+        )
+
+    def __ne__(self, other):
+        return not self == other
+
+    p = utils.read_only_property("_p")
+    g = utils.read_only_property("_g")
+
+
+@six.add_metaclass(abc.ABCMeta)
+class DHParameters(object):
+    @abc.abstractmethod
+    def generate_private_key(self):
+        """
+        Generates and returns a DHPrivateKey.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class DHParametersWithSerialization(DHParameters):
+    @abc.abstractmethod
+    def parameter_numbers(self):
+        """
+        Returns a DHParameterNumbers.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class DHPrivateKey(object):
+    @abc.abstractproperty
+    def key_size(self):
+        """
+        The bit length of the prime modulus.
+        """
+
+    @abc.abstractmethod
+    def public_key(self):
+        """
+        The DHPublicKey associated with this private key.
+        """
+
+    @abc.abstractmethod
+    def parameters(self):
+        """
+        The DHParameters object associated with this private key.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class DHPrivateKeyWithSerialization(DHPrivateKey):
+    @abc.abstractmethod
+    def private_numbers(self):
+        """
+        Returns a DHPrivateNumbers.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class DHPublicKey(object):
+    @abc.abstractproperty
+    def key_size(self):
+        """
+        The bit length of the prime modulus.
+        """
+
+    @abc.abstractmethod
+    def parameters(self):
+        """
+        The DHParameters object associated with this public key.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class DHPublicKeyWithSerialization(DHPublicKey):
+    @abc.abstractmethod
+    def public_numbers(self):
+        """
+        Returns a DHPublicNumbers.
+        """

lib/python3.5/site-packages/cryptography/hazmat/primitives/asymmetric/dsa.py

@@ -0,0 +1,229 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import abc
+
+import six
+
+from cryptography import utils
+
+
+@six.add_metaclass(abc.ABCMeta)
+class DSAParameters(object):
+    @abc.abstractmethod
+    def generate_private_key(self):
+        """
+        Generates and returns a DSAPrivateKey.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class DSAParametersWithNumbers(DSAParameters):
+    @abc.abstractmethod
+    def parameter_numbers(self):
+        """
+        Returns a DSAParameterNumbers.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class DSAPrivateKey(object):
+    @abc.abstractproperty
+    def key_size(self):
+        """
+        The bit length of the prime modulus.
+        """
+
+    @abc.abstractmethod
+    def public_key(self):
+        """
+        The DSAPublicKey associated with this private key.
+        """
+
+    @abc.abstractmethod
+    def parameters(self):
+        """
+        The DSAParameters object associated with this private key.
+        """
+
+    @abc.abstractmethod
+    def signer(self, signature_algorithm):
+        """
+        Returns an AsymmetricSignatureContext used for signing data.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class DSAPrivateKeyWithSerialization(DSAPrivateKey):
+    @abc.abstractmethod
+    def private_numbers(self):
+        """
+        Returns a DSAPrivateNumbers.
+        """
+
+    @abc.abstractmethod
+    def private_bytes(self, encoding, format, encryption_algorithm):
+        """
+        Returns the key serialized as bytes.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class DSAPublicKey(object):
+    @abc.abstractproperty
+    def key_size(self):
+        """
+        The bit length of the prime modulus.
+        """
+
+    @abc.abstractmethod
+    def parameters(self):
+        """
+        The DSAParameters object associated with this public key.
+        """
+
+    @abc.abstractmethod
+    def verifier(self, signature, signature_algorithm):
+        """
+        Returns an AsymmetricVerificationContext used for signing data.
+        """
+
+    @abc.abstractmethod
+    def public_numbers(self):
+        """
+        Returns a DSAPublicNumbers.
+        """
+
+    @abc.abstractmethod
+    def public_bytes(self, encoding, format):
+        """
+        Returns the key serialized as bytes.
+        """
+
+
+DSAPublicKeyWithSerialization = DSAPublicKey
+
+
+def generate_parameters(key_size, backend):
+    return backend.generate_dsa_parameters(key_size)
+
+
+def generate_private_key(key_size, backend):
+    return backend.generate_dsa_private_key_and_parameters(key_size)
+
+
+def _check_dsa_parameters(parameters):
+    if utils.bit_length(parameters.p) not in [1024, 2048, 3072]:
+        raise ValueError("p must be exactly 1024, 2048, or 3072 bits long")
+    if utils.bit_length(parameters.q) not in [160, 256]:
+        raise ValueError("q must be exactly 160 or 256 bits long")
+
+    if not (1 < parameters.g < parameters.p):
+        raise ValueError("g, p don't satisfy 1 < g < p.")
+
+
+def _check_dsa_private_numbers(numbers):
+    parameters = numbers.public_numbers.parameter_numbers
+    _check_dsa_parameters(parameters)
+    if numbers.x <= 0 or numbers.x >= parameters.q:
+        raise ValueError("x must be > 0 and < q.")
+
+    if numbers.public_numbers.y != pow(parameters.g, numbers.x, parameters.p):
+        raise ValueError("y must be equal to (g ** x % p).")
+
+
+class DSAParameterNumbers(object):
+    def __init__(self, p, q, g):
+        if (
+            not isinstance(p, six.integer_types) or
+            not isinstance(q, six.integer_types) or
+            not isinstance(g, six.integer_types)
+        ):
+            raise TypeError(
+                "DSAParameterNumbers p, q, and g arguments must be integers."
+            )
+
+        self._p = p
+        self._q = q
+        self._g = g
+
+    p = utils.read_only_property("_p")
+    q = utils.read_only_property("_q")
+    g = utils.read_only_property("_g")
+
+    def parameters(self, backend):
+        return backend.load_dsa_parameter_numbers(self)
+
+    def __eq__(self, other):
+        if not isinstance(other, DSAParameterNumbers):
+            return NotImplemented
+
+        return self.p == other.p and self.q == other.q and self.g == other.g
+
+    def __ne__(self, other):
+        return not self == other
+
+
+class DSAPublicNumbers(object):
+    def __init__(self, y, parameter_numbers):
+        if not isinstance(y, six.integer_types):
+            raise TypeError("DSAPublicNumbers y argument must be an integer.")
+
+        if not isinstance(parameter_numbers, DSAParameterNumbers):
+            raise TypeError(
+                "parameter_numbers must be a DSAParameterNumbers instance."
+            )
+
+        self._y = y
+        self._parameter_numbers = parameter_numbers
+
+    y = utils.read_only_property("_y")
+    parameter_numbers = utils.read_only_property("_parameter_numbers")
+
+    def public_key(self, backend):
+        return backend.load_dsa_public_numbers(self)
+
+    def __eq__(self, other):
+        if not isinstance(other, DSAPublicNumbers):
+            return NotImplemented
+
+        return (
+            self.y == other.y and
+            self.parameter_numbers == other.parameter_numbers
+        )
+
+    def __ne__(self, other):
+        return not self == other
+
+
+class DSAPrivateNumbers(object):
+    def __init__(self, x, public_numbers):
+        if not isinstance(x, six.integer_types):
+            raise TypeError("DSAPrivateNumbers x argument must be an integer.")
+
+        if not isinstance(public_numbers, DSAPublicNumbers):
+            raise TypeError(
+                "public_numbers must be a DSAPublicNumbers instance."
+            )
+        self._public_numbers = public_numbers
+        self._x = x
+
+    x = utils.read_only_property("_x")
+    public_numbers = utils.read_only_property("_public_numbers")
+
+    def private_key(self, backend):
+        return backend.load_dsa_private_numbers(self)
+
+    def __eq__(self, other):
+        if not isinstance(other, DSAPrivateNumbers):
+            return NotImplemented
+
+        return (
+            self.x == other.x and self.public_numbers == other.public_numbers
+        )
+
+    def __ne__(self, other):
+        return not self == other

lib/python3.5/site-packages/cryptography/hazmat/primitives/asymmetric/ec.py

@@ -0,0 +1,346 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import abc
+
+import six
+
+from cryptography import utils
+
+
+@six.add_metaclass(abc.ABCMeta)
+class EllipticCurve(object):
+    @abc.abstractproperty
+    def name(self):
+        """
+        The name of the curve. e.g. secp256r1.
+        """
+
+    @abc.abstractproperty
+    def key_size(self):
+        """
+        The bit length of the base point of the curve.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class EllipticCurveSignatureAlgorithm(object):
+    @abc.abstractproperty
+    def algorithm(self):
+        """
+        The digest algorithm used with this signature.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class EllipticCurvePrivateKey(object):
+    @abc.abstractmethod
+    def signer(self, signature_algorithm):
+        """
+        Returns an AsymmetricSignatureContext used for signing data.
+        """
+
+    @abc.abstractmethod
+    def exchange(self, algorithm, peer_public_key):
+        """
+        Performs a key exchange operation using the provided algorithm with the
+        provided peer's public key.
+        """
+
+    @abc.abstractmethod
+    def public_key(self):
+        """
+        The EllipticCurvePublicKey for this private key.
+        """
+
+    @abc.abstractproperty
+    def curve(self):
+        """
+        The EllipticCurve that this key is on.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class EllipticCurvePrivateKeyWithSerialization(EllipticCurvePrivateKey):
+    @abc.abstractmethod
+    def private_numbers(self):
+        """
+        Returns an EllipticCurvePrivateNumbers.
+        """
+
+    @abc.abstractmethod
+    def private_bytes(self, encoding, format, encryption_algorithm):
+        """
+        Returns the key serialized as bytes.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class EllipticCurvePublicKey(object):
+    @abc.abstractmethod
+    def verifier(self, signature, signature_algorithm):
+        """
+        Returns an AsymmetricVerificationContext used for signing data.
+        """
+
+    @abc.abstractproperty
+    def curve(self):
+        """
+        The EllipticCurve that this key is on.
+        """
+
+    @abc.abstractmethod
+    def public_numbers(self):
+        """
+        Returns an EllipticCurvePublicNumbers.
+        """
+
+    @abc.abstractmethod
+    def public_bytes(self, encoding, format):
+        """
+        Returns the key serialized as bytes.
+        """
+
+
+EllipticCurvePublicKeyWithSerialization = EllipticCurvePublicKey
+
+
+@utils.register_interface(EllipticCurve)
+class SECT571R1(object):
+    name = "sect571r1"
+    key_size = 571
+
+
+@utils.register_interface(EllipticCurve)
+class SECT409R1(object):
+    name = "sect409r1"
+    key_size = 409
+
+
+@utils.register_interface(EllipticCurve)
+class SECT283R1(object):
+    name = "sect283r1"
+    key_size = 283
+
+
+@utils.register_interface(EllipticCurve)
+class SECT233R1(object):
+    name = "sect233r1"
+    key_size = 233
+
+
+@utils.register_interface(EllipticCurve)
+class SECT163R2(object):
+    name = "sect163r2"
+    key_size = 163
+
+
+@utils.register_interface(EllipticCurve)
+class SECT571K1(object):
+    name = "sect571k1"
+    key_size = 571
+
+
+@utils.register_interface(EllipticCurve)
+class SECT409K1(object):
+    name = "sect409k1"
+    key_size = 409
+
+
+@utils.register_interface(EllipticCurve)
+class SECT283K1(object):
+    name = "sect283k1"
+    key_size = 283
+
+
+@utils.register_interface(EllipticCurve)
+class SECT233K1(object):
+    name = "sect233k1"
+    key_size = 233
+
+
+@utils.register_interface(EllipticCurve)
+class SECT163K1(object):
+    name = "sect163k1"
+    key_size = 163
+
+
+@utils.register_interface(EllipticCurve)
+class SECP521R1(object):
+    name = "secp521r1"
+    key_size = 521
+
+
+@utils.register_interface(EllipticCurve)
+class SECP384R1(object):
+    name = "secp384r1"
+    key_size = 384
+
+
+@utils.register_interface(EllipticCurve)
+class SECP256R1(object):
+    name = "secp256r1"
+    key_size = 256
+
+
+@utils.register_interface(EllipticCurve)
+class SECP256K1(object):
+    name = "secp256k1"
+    key_size = 256
+
+
+@utils.register_interface(EllipticCurve)
+class SECP224R1(object):
+    name = "secp224r1"
+    key_size = 224
+
+
+@utils.register_interface(EllipticCurve)
+class SECP192R1(object):
+    name = "secp192r1"
+    key_size = 192
+
+
+_CURVE_TYPES = {
+    "prime192v1": SECP192R1,
+    "prime256v1": SECP256R1,
+
+    "secp192r1": SECP192R1,
+    "secp224r1": SECP224R1,
+    "secp256r1": SECP256R1,
+    "secp384r1": SECP384R1,
+    "secp521r1": SECP521R1,
+    "secp256k1": SECP256K1,
+
+    "sect163k1": SECT163K1,
+    "sect233k1": SECT233K1,
+    "sect283k1": SECT283K1,
+    "sect409k1": SECT409K1,
+    "sect571k1": SECT571K1,
+
+    "sect163r2": SECT163R2,
+    "sect233r1": SECT233R1,
+    "sect283r1": SECT283R1,
+    "sect409r1": SECT409R1,
+    "sect571r1": SECT571R1,
+}
+
+
+@utils.register_interface(EllipticCurveSignatureAlgorithm)
+class ECDSA(object):
+    def __init__(self, algorithm):
+        self._algorithm = algorithm
+
+    algorithm = utils.read_only_property("_algorithm")
+
+
+def generate_private_key(curve, backend):
+    return backend.generate_elliptic_curve_private_key(curve)
+
+
+class EllipticCurvePublicNumbers(object):
+    def __init__(self, x, y, curve):
+        if (
+            not isinstance(x, six.integer_types) or
+            not isinstance(y, six.integer_types)
+        ):
+            raise TypeError("x and y must be integers.")
+
+        if not isinstance(curve, EllipticCurve):
+            raise TypeError("curve must provide the EllipticCurve interface.")
+
+        self._y = y
+        self._x = x
+        self._curve = curve
+
+    def public_key(self, backend):
+        return backend.load_elliptic_curve_public_numbers(self)
+
+    def encode_point(self):
+        # key_size is in bits. Convert to bytes and round up
+        byte_length = (self.curve.key_size + 7) // 8
+        return (
+            b'\x04' + utils.int_to_bytes(self.x, byte_length) +
+            utils.int_to_bytes(self.y, byte_length)
+        )
+
+    @classmethod
+    def from_encoded_point(cls, curve, data):
+        if not isinstance(curve, EllipticCurve):
+            raise TypeError("curve must be an EllipticCurve instance")
+
+        if data.startswith(b'\x04'):
+            # key_size is in bits. Convert to bytes and round up
+            byte_length = (curve.key_size + 7) // 8
+            if len(data) == 2 * byte_length + 1:
+                x = utils.int_from_bytes(data[1:byte_length + 1], 'big')
+                y = utils.int_from_bytes(data[byte_length + 1:], 'big')
+                return cls(x, y, curve)
+            else:
+                raise ValueError('Invalid elliptic curve point data length')
+        else:
+            raise ValueError('Unsupported elliptic curve point type')
+
+    curve = utils.read_only_property("_curve")
+    x = utils.read_only_property("_x")
+    y = utils.read_only_property("_y")
+
+    def __eq__(self, other):
+        if not isinstance(other, EllipticCurvePublicNumbers):
+            return NotImplemented
+
+        return (
+            self.x == other.x and
+            self.y == other.y and
+            self.curve.name == other.curve.name and
+            self.curve.key_size == other.curve.key_size
+        )
+
+    def __ne__(self, other):
+        return not self == other
+
+    def __repr__(self):
+        return (
+            "<EllipticCurvePublicNumbers(curve={0.curve.name}, x={0.x}, "
+            "y={0.y}>".format(self)
+        )
+
+
+class EllipticCurvePrivateNumbers(object):
+    def __init__(self, private_value, public_numbers):
+        if not isinstance(private_value, six.integer_types):
+            raise TypeError("private_value must be an integer.")
+
+        if not isinstance(public_numbers, EllipticCurvePublicNumbers):
+            raise TypeError(
+                "public_numbers must be an EllipticCurvePublicNumbers "
+                "instance."
+            )
+
+        self._private_value = private_value
+        self._public_numbers = public_numbers
+
+    def private_key(self, backend):
+        return backend.load_elliptic_curve_private_numbers(self)
+
+    private_value = utils.read_only_property("_private_value")
+    public_numbers = utils.read_only_property("_public_numbers")
+
+    def __eq__(self, other):
+        if not isinstance(other, EllipticCurvePrivateNumbers):
+            return NotImplemented
+
+        return (
+            self.private_value == other.private_value and
+            self.public_numbers == other.public_numbers
+        )
+
+    def __ne__(self, other):
+        return not self == other
+
+
+class ECDH(object):
+    pass

lib/python3.5/site-packages/cryptography/hazmat/primitives/asymmetric/padding.py

@@ -0,0 +1,67 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import abc
+
+import six
+
+from cryptography import utils
+from cryptography.hazmat.primitives import hashes
+
+
+@six.add_metaclass(abc.ABCMeta)
+class AsymmetricPadding(object):
+    @abc.abstractproperty
+    def name(self):
+        """
+        A string naming this padding (e.g. "PSS", "PKCS1").
+        """
+
+
+@utils.register_interface(AsymmetricPadding)
+class PKCS1v15(object):
+    name = "EMSA-PKCS1-v1_5"
+
+
+@utils.register_interface(AsymmetricPadding)
+class PSS(object):
+    MAX_LENGTH = object()
+    name = "EMSA-PSS"
+
+    def __init__(self, mgf, salt_length):
+        self._mgf = mgf
+
+        if (not isinstance(salt_length, six.integer_types) and
+                salt_length is not self.MAX_LENGTH):
+            raise TypeError("salt_length must be an integer.")
+
+        if salt_length is not self.MAX_LENGTH and salt_length < 0:
+            raise ValueError("salt_length must be zero or greater.")
+
+        self._salt_length = salt_length
+
+
+@utils.register_interface(AsymmetricPadding)
+class OAEP(object):
+    name = "EME-OAEP"
+
+    def __init__(self, mgf, algorithm, label):
+        if not isinstance(algorithm, hashes.HashAlgorithm):
+            raise TypeError("Expected instance of hashes.HashAlgorithm.")
+
+        self._mgf = mgf
+        self._algorithm = algorithm
+        self._label = label
+
+
+class MGF1(object):
+    MAX_LENGTH = object()
+
+    def __init__(self, algorithm):
+        if not isinstance(algorithm, hashes.HashAlgorithm):
+            raise TypeError("Expected instance of hashes.HashAlgorithm.")
+
+        self._algorithm = algorithm

lib/python3.5/site-packages/cryptography/hazmat/primitives/asymmetric/rsa.py

@@ -0,0 +1,352 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import abc
+from fractions import gcd
+
+import six
+
+from cryptography import utils
+from cryptography.exceptions import UnsupportedAlgorithm, _Reasons
+from cryptography.hazmat.backends.interfaces import RSABackend
+
+
+@six.add_metaclass(abc.ABCMeta)
+class RSAPrivateKey(object):
+    @abc.abstractmethod
+    def signer(self, padding, algorithm):
+        """
+        Returns an AsymmetricSignatureContext used for signing data.
+        """
+
+    @abc.abstractmethod
+    def decrypt(self, ciphertext, padding):
+        """
+        Decrypts the provided ciphertext.
+        """
+
+    @abc.abstractproperty
+    def key_size(self):
+        """
+        The bit length of the public modulus.
+        """
+
+    @abc.abstractmethod
+    def public_key(self):
+        """
+        The RSAPublicKey associated with this private key.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class RSAPrivateKeyWithSerialization(RSAPrivateKey):
+    @abc.abstractmethod
+    def private_numbers(self):
+        """
+        Returns an RSAPrivateNumbers.
+        """
+
+    @abc.abstractmethod
+    def private_bytes(self, encoding, format, encryption_algorithm):
+        """
+        Returns the key serialized as bytes.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class RSAPublicKey(object):
+    @abc.abstractmethod
+    def verifier(self, signature, padding, algorithm):
+        """
+        Returns an AsymmetricVerificationContext used for verifying signatures.
+        """
+
+    @abc.abstractmethod
+    def encrypt(self, plaintext, padding):
+        """
+        Encrypts the given plaintext.
+        """
+
+    @abc.abstractproperty
+    def key_size(self):
+        """
+        The bit length of the public modulus.
+        """
+
+    @abc.abstractmethod
+    def public_numbers(self):
+        """
+        Returns an RSAPublicNumbers
+        """
+
+    @abc.abstractmethod
+    def public_bytes(self, encoding, format):
+        """
+        Returns the key serialized as bytes.
+        """
+
+
+RSAPublicKeyWithSerialization = RSAPublicKey
+
+
+def generate_private_key(public_exponent, key_size, backend):
+    if not isinstance(backend, RSABackend):
+        raise UnsupportedAlgorithm(
+            "Backend object does not implement RSABackend.",
+            _Reasons.BACKEND_MISSING_INTERFACE
+        )
+
+    _verify_rsa_parameters(public_exponent, key_size)
+    return backend.generate_rsa_private_key(public_exponent, key_size)
+
+
+def _verify_rsa_parameters(public_exponent, key_size):
+    if public_exponent < 3:
+        raise ValueError("public_exponent must be >= 3.")
+
+    if public_exponent & 1 == 0:
+        raise ValueError("public_exponent must be odd.")
+
+    if key_size < 512:
+        raise ValueError("key_size must be at least 512-bits.")
+
+
+def _check_private_key_components(p, q, private_exponent, dmp1, dmq1, iqmp,
+                                  public_exponent, modulus):
+    if modulus < 3:
+        raise ValueError("modulus must be >= 3.")
+
+    if p >= modulus:
+        raise ValueError("p must be < modulus.")
+
+    if q >= modulus:
+        raise ValueError("q must be < modulus.")
+
+    if dmp1 >= modulus:
+        raise ValueError("dmp1 must be < modulus.")
+
+    if dmq1 >= modulus:
+        raise ValueError("dmq1 must be < modulus.")
+
+    if iqmp >= modulus:
+        raise ValueError("iqmp must be < modulus.")
+
+    if private_exponent >= modulus:
+        raise ValueError("private_exponent must be < modulus.")
+
+    if public_exponent < 3 or public_exponent >= modulus:
+        raise ValueError("public_exponent must be >= 3 and < modulus.")
+
+    if public_exponent & 1 == 0:
+        raise ValueError("public_exponent must be odd.")
+
+    if dmp1 & 1 == 0:
+        raise ValueError("dmp1 must be odd.")
+
+    if dmq1 & 1 == 0:
+        raise ValueError("dmq1 must be odd.")
+
+    if p * q != modulus:
+        raise ValueError("p*q must equal modulus.")
+
+
+def _check_public_key_components(e, n):
+    if n < 3:
+        raise ValueError("n must be >= 3.")
+
+    if e < 3 or e >= n:
+        raise ValueError("e must be >= 3 and < n.")
+
+    if e & 1 == 0:
+        raise ValueError("e must be odd.")
+
+
+def _modinv(e, m):
+    """
+    Modular Multiplicative Inverse. Returns x such that: (x*e) mod m == 1
+    """
+    x1, y1, x2, y2 = 1, 0, 0, 1
+    a, b = e, m
+    while b > 0:
+        q, r = divmod(a, b)
+        xn, yn = x1 - q * x2, y1 - q * y2
+        a, b, x1, y1, x2, y2 = b, r, x2, y2, xn, yn
+    return x1 % m
+
+
+def rsa_crt_iqmp(p, q):
+    """
+    Compute the CRT (q ** -1) % p value from RSA primes p and q.
+    """
+    return _modinv(q, p)
+
+
+def rsa_crt_dmp1(private_exponent, p):
+    """
+    Compute the CRT private_exponent % (p - 1) value from the RSA
+    private_exponent and p.
+    """
+    return private_exponent % (p - 1)
+
+
+def rsa_crt_dmq1(private_exponent, q):
+    """
+    Compute the CRT private_exponent % (q - 1) value from the RSA
+    private_exponent and q.
+    """
+    return private_exponent % (q - 1)
+
+
+# Controls the number of iterations rsa_recover_prime_factors will perform
+# to obtain the prime factors. Each iteration increments by 2 so the actual
+# maximum attempts is half this number.
+_MAX_RECOVERY_ATTEMPTS = 1000
+
+
+def rsa_recover_prime_factors(n, e, d):
+    """
+    Compute factors p and q from the private exponent d. We assume that n has
+    no more than two factors. This function is adapted from code in PyCrypto.
+    """
+    # See 8.2.2(i) in Handbook of Applied Cryptography.
+    ktot = d * e - 1
+    # The quantity d*e-1 is a multiple of phi(n), even,
+    # and can be represented as t*2^s.
+    t = ktot
+    while t % 2 == 0:
+        t = t // 2
+    # Cycle through all multiplicative inverses in Zn.
+    # The algorithm is non-deterministic, but there is a 50% chance
+    # any candidate a leads to successful factoring.
+    # See "Digitalized Signatures and Public Key Functions as Intractable
+    # as Factorization", M. Rabin, 1979
+    spotted = False
+    a = 2
+    while not spotted and a < _MAX_RECOVERY_ATTEMPTS:
+        k = t
+        # Cycle through all values a^{t*2^i}=a^k
+        while k < ktot:
+            cand = pow(a, k, n)
+            # Check if a^k is a non-trivial root of unity (mod n)
+            if cand != 1 and cand != (n - 1) and pow(cand, 2, n) == 1:
+                # We have found a number such that (cand-1)(cand+1)=0 (mod n).
+                # Either of the terms divides n.
+                p = gcd(cand + 1, n)
+                spotted = True
+                break
+            k *= 2
+        # This value was not any good... let's try another!
+        a += 2
+    if not spotted:
+        raise ValueError("Unable to compute factors p and q from exponent d.")
+    # Found !
+    q, r = divmod(n, p)
+    assert r == 0
+
+    return (p, q)
+
+
+class RSAPrivateNumbers(object):
+    def __init__(self, p, q, d, dmp1, dmq1, iqmp,
+                 public_numbers):
+        if (
+            not isinstance(p, six.integer_types) or
+            not isinstance(q, six.integer_types) or
+            not isinstance(d, six.integer_types) or
+            not isinstance(dmp1, six.integer_types) or
+            not isinstance(dmq1, six.integer_types) or
+            not isinstance(iqmp, six.integer_types)
+        ):
+            raise TypeError(
+                "RSAPrivateNumbers p, q, d, dmp1, dmq1, iqmp arguments must"
+                " all be an integers."
+            )
+
+        if not isinstance(public_numbers, RSAPublicNumbers):
+            raise TypeError(
+                "RSAPrivateNumbers public_numbers must be an RSAPublicNumbers"
+                " instance."
+            )
+
+        self._p = p
+        self._q = q
+        self._d = d
+        self._dmp1 = dmp1
+        self._dmq1 = dmq1
+        self._iqmp = iqmp
+        self._public_numbers = public_numbers
+
+    p = utils.read_only_property("_p")
+    q = utils.read_only_property("_q")
+    d = utils.read_only_property("_d")
+    dmp1 = utils.read_only_property("_dmp1")
+    dmq1 = utils.read_only_property("_dmq1")
+    iqmp = utils.read_only_property("_iqmp")
+    public_numbers = utils.read_only_property("_public_numbers")
+
+    def private_key(self, backend):
+        return backend.load_rsa_private_numbers(self)
+
+    def __eq__(self, other):
+        if not isinstance(other, RSAPrivateNumbers):
+            return NotImplemented
+
+        return (
+            self.p == other.p and
+            self.q == other.q and
+            self.d == other.d and
+            self.dmp1 == other.dmp1 and
+            self.dmq1 == other.dmq1 and
+            self.iqmp == other.iqmp and
+            self.public_numbers == other.public_numbers
+        )
+
+    def __ne__(self, other):
+        return not self == other
+
+    def __hash__(self):
+        return hash((
+            self.p,
+            self.q,
+            self.d,
+            self.dmp1,
+            self.dmq1,
+            self.iqmp,
+            self.public_numbers,
+        ))
+
+
+class RSAPublicNumbers(object):
+    def __init__(self, e, n):
+        if (
+            not isinstance(e, six.integer_types) or
+            not isinstance(n, six.integer_types)
+        ):
+            raise TypeError("RSAPublicNumbers arguments must be integers.")
+
+        self._e = e
+        self._n = n
+
+    e = utils.read_only_property("_e")
+    n = utils.read_only_property("_n")
+
+    def public_key(self, backend):
+        return backend.load_rsa_public_numbers(self)
+
+    def __repr__(self):
+        return "<RSAPublicNumbers(e={0.e}, n={0.n})>".format(self)
+
+    def __eq__(self, other):
+        if not isinstance(other, RSAPublicNumbers):
+            return NotImplemented
+
+        return self.e == other.e and self.n == other.n
+
+    def __ne__(self, other):
+        return not self == other
+
+    def __hash__(self):
+        return hash((self.e, self.n))

lib/python3.5/site-packages/cryptography/hazmat/primitives/asymmetric/utils.py

@@ -0,0 +1,73 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import warnings
+
+from pyasn1.codec.der import decoder, encoder
+from pyasn1.error import PyAsn1Error
+from pyasn1.type import namedtype, univ
+
+import six
+
+from cryptography import utils
+
+
+class _DSSSigValue(univ.Sequence):
+    componentType = namedtype.NamedTypes(
+        namedtype.NamedType('r', univ.Integer()),
+        namedtype.NamedType('s', univ.Integer())
+    )
+
+
+def decode_rfc6979_signature(signature):
+    warnings.warn(
+        "decode_rfc6979_signature is deprecated and will "
+        "be removed in a future version, use decode_dss_signature instead "
+        "instead.",
+        utils.DeprecatedIn10,
+        stacklevel=2
+    )
+    return decode_dss_signature(signature)
+
+
+def decode_dss_signature(signature):
+    try:
+        data, remaining = decoder.decode(signature, asn1Spec=_DSSSigValue())
+    except PyAsn1Error:
+        raise ValueError("Invalid signature data. Unable to decode ASN.1")
+
+    if remaining:
+        raise ValueError(
+            "The signature contains bytes after the end of the ASN.1 sequence."
+        )
+
+    r = int(data.getComponentByName('r'))
+    s = int(data.getComponentByName('s'))
+    return (r, s)
+
+
+def encode_rfc6979_signature(r, s):
+    warnings.warn(
+        "encode_rfc6979_signature is deprecated and will "
+        "be removed in a future version, use encode_dss_signature instead "
+        "instead.",
+        utils.DeprecatedIn10,
+        stacklevel=2
+    )
+    return encode_dss_signature(r, s)
+
+
+def encode_dss_signature(r, s):
+    if (
+        not isinstance(r, six.integer_types) or
+        not isinstance(s, six.integer_types)
+    ):
+        raise ValueError("Both r and s must be integers")
+
+    sig = _DSSSigValue()
+    sig.setComponentByName('r', r)
+    sig.setComponentByName('s', s)
+    return encoder.encode(sig)

lib/python3.5/site-packages/cryptography/hazmat/primitives/ciphers/__init__.py

@@ -0,0 +1,20 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+from cryptography.hazmat.primitives.ciphers.base import (
+    AEADCipherContext, AEADEncryptionContext, BlockCipherAlgorithm, Cipher,
+    CipherAlgorithm, CipherContext
+)
+
+
+__all__ = [
+    "Cipher",
+    "CipherAlgorithm",
+    "BlockCipherAlgorithm",
+    "CipherContext",
+    "AEADCipherContext",
+    "AEADEncryptionContext",
+]

lib/python3.5/site-packages/cryptography/hazmat/primitives/ciphers/algorithms.py

@@ -0,0 +1,140 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+from cryptography import utils
+from cryptography.hazmat.primitives.ciphers import (
+    BlockCipherAlgorithm, CipherAlgorithm
+)
+
+
+def _verify_key_size(algorithm, key):
+    # Verify that the key size matches the expected key size
+    if len(key) * 8 not in algorithm.key_sizes:
+        raise ValueError("Invalid key size ({0}) for {1}.".format(
+            len(key) * 8, algorithm.name
+        ))
+    return key
+
+
+@utils.register_interface(BlockCipherAlgorithm)
+@utils.register_interface(CipherAlgorithm)
+class AES(object):
+    name = "AES"
+    block_size = 128
+    key_sizes = frozenset([128, 192, 256])
+
+    def __init__(self, key):
+        self.key = _verify_key_size(self, key)
+
+    @property
+    def key_size(self):
+        return len(self.key) * 8
+
+
+@utils.register_interface(BlockCipherAlgorithm)
+@utils.register_interface(CipherAlgorithm)
+class Camellia(object):
+    name = "camellia"
+    block_size = 128
+    key_sizes = frozenset([128, 192, 256])
+
+    def __init__(self, key):
+        self.key = _verify_key_size(self, key)
+
+    @property
+    def key_size(self):
+        return len(self.key) * 8
+
+
+@utils.register_interface(BlockCipherAlgorithm)
+@utils.register_interface(CipherAlgorithm)
+class TripleDES(object):
+    name = "3DES"
+    block_size = 64
+    key_sizes = frozenset([64, 128, 192])
+
+    def __init__(self, key):
+        if len(key) == 8:
+            key += key + key
+        elif len(key) == 16:
+            key += key[:8]
+        self.key = _verify_key_size(self, key)
+
+    @property
+    def key_size(self):
+        return len(self.key) * 8
+
+
+@utils.register_interface(BlockCipherAlgorithm)
+@utils.register_interface(CipherAlgorithm)
+class Blowfish(object):
+    name = "Blowfish"
+    block_size = 64
+    key_sizes = frozenset(range(32, 449, 8))
+
+    def __init__(self, key):
+        self.key = _verify_key_size(self, key)
+
+    @property
+    def key_size(self):
+        return len(self.key) * 8
+
+
+@utils.register_interface(BlockCipherAlgorithm)
+@utils.register_interface(CipherAlgorithm)
+class CAST5(object):
+    name = "CAST5"
+    block_size = 64
+    key_sizes = frozenset(range(40, 129, 8))
+
+    def __init__(self, key):
+        self.key = _verify_key_size(self, key)
+
+    @property
+    def key_size(self):
+        return len(self.key) * 8
+
+
+@utils.register_interface(CipherAlgorithm)
+class ARC4(object):
+    name = "RC4"
+    key_sizes = frozenset([40, 56, 64, 80, 128, 192, 256])
+
+    def __init__(self, key):
+        self.key = _verify_key_size(self, key)
+
+    @property
+    def key_size(self):
+        return len(self.key) * 8
+
+
+@utils.register_interface(CipherAlgorithm)
+class IDEA(object):
+    name = "IDEA"
+    block_size = 64
+    key_sizes = frozenset([128])
+
+    def __init__(self, key):
+        self.key = _verify_key_size(self, key)
+
+    @property
+    def key_size(self):
+        return len(self.key) * 8
+
+
+@utils.register_interface(BlockCipherAlgorithm)
+@utils.register_interface(CipherAlgorithm)
+class SEED(object):
+    name = "SEED"
+    block_size = 128
+    key_sizes = frozenset([128])
+
+    def __init__(self, key):
+        self.key = _verify_key_size(self, key)
+
+    @property
+    def key_size(self):
+        return len(self.key) * 8

lib/python3.5/site-packages/cryptography/hazmat/primitives/ciphers/base.py

@@ -0,0 +1,203 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import abc
+
+import six
+
+from cryptography import utils
+from cryptography.exceptions import (
+    AlreadyFinalized, AlreadyUpdated, NotYetFinalized, UnsupportedAlgorithm,
+    _Reasons
+)
+from cryptography.hazmat.backends.interfaces import CipherBackend
+from cryptography.hazmat.primitives.ciphers import modes
+
+
+@six.add_metaclass(abc.ABCMeta)
+class CipherAlgorithm(object):
+    @abc.abstractproperty
+    def name(self):
+        """
+        A string naming this mode (e.g. "AES", "Camellia").
+        """
+
+    @abc.abstractproperty
+    def key_size(self):
+        """
+        The size of the key being used as an integer in bits (e.g. 128, 256).
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class BlockCipherAlgorithm(object):
+    @abc.abstractproperty
+    def block_size(self):
+        """
+        The size of a block as an integer in bits (e.g. 64, 128).
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class CipherContext(object):
+    @abc.abstractmethod
+    def update(self, data):
+        """
+        Processes the provided bytes through the cipher and returns the results
+        as bytes.
+        """
+
+    @abc.abstractmethod
+    def finalize(self):
+        """
+        Returns the results of processing the final block as bytes.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class AEADCipherContext(object):
+    @abc.abstractmethod
+    def authenticate_additional_data(self, data):
+        """
+        Authenticates the provided bytes.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class AEADEncryptionContext(object):
+    @abc.abstractproperty
+    def tag(self):
+        """
+        Returns tag bytes. This is only available after encryption is
+        finalized.
+        """
+
+
+class Cipher(object):
+    def __init__(self, algorithm, mode, backend):
+        if not isinstance(backend, CipherBackend):
+            raise UnsupportedAlgorithm(
+                "Backend object does not implement CipherBackend.",
+                _Reasons.BACKEND_MISSING_INTERFACE
+            )
+
+        if not isinstance(algorithm, CipherAlgorithm):
+            raise TypeError("Expected interface of CipherAlgorithm.")
+
+        if mode is not None:
+            mode.validate_for_algorithm(algorithm)
+
+        self.algorithm = algorithm
+        self.mode = mode
+        self._backend = backend
+
+    def encryptor(self):
+        if isinstance(self.mode, modes.ModeWithAuthenticationTag):
+            if self.mode.tag is not None:
+                raise ValueError(
+                    "Authentication tag must be None when encrypting."
+                )
+        ctx = self._backend.create_symmetric_encryption_ctx(
+            self.algorithm, self.mode
+        )
+        return self._wrap_ctx(ctx, encrypt=True)
+
+    def decryptor(self):
+        if isinstance(self.mode, modes.ModeWithAuthenticationTag):
+            if self.mode.tag is None:
+                raise ValueError(
+                    "Authentication tag must be provided when decrypting."
+                )
+        ctx = self._backend.create_symmetric_decryption_ctx(
+            self.algorithm, self.mode
+        )
+        return self._wrap_ctx(ctx, encrypt=False)
+
+    def _wrap_ctx(self, ctx, encrypt):
+        if isinstance(self.mode, modes.ModeWithAuthenticationTag):
+            if encrypt:
+                return _AEADEncryptionContext(ctx)
+            else:
+                return _AEADCipherContext(ctx)
+        else:
+            return _CipherContext(ctx)
+
+
+@utils.register_interface(CipherContext)
+class _CipherContext(object):
+    def __init__(self, ctx):
+        self._ctx = ctx
+
+    def update(self, data):
+        if self._ctx is None:
+            raise AlreadyFinalized("Context was already finalized.")
+        return self._ctx.update(data)
+
+    def finalize(self):
+        if self._ctx is None:
+            raise AlreadyFinalized("Context was already finalized.")
+        data = self._ctx.finalize()
+        self._ctx = None
+        return data
+
+
+@utils.register_interface(AEADCipherContext)
+@utils.register_interface(CipherContext)
+class _AEADCipherContext(object):
+    def __init__(self, ctx):
+        self._ctx = ctx
+        self._bytes_processed = 0
+        self._aad_bytes_processed = 0
+        self._tag = None
+        self._updated = False
+
+    def update(self, data):
+        if self._ctx is None:
+            raise AlreadyFinalized("Context was already finalized.")
+        self._updated = True
+        self._bytes_processed += len(data)
+        if self._bytes_processed > self._ctx._mode._MAX_ENCRYPTED_BYTES:
+            raise ValueError(
+                "{0} has a maximum encrypted byte limit of {1}".format(
+                    self._ctx._mode.name, self._ctx._mode._MAX_ENCRYPTED_BYTES
+                )
+            )
+
+        return self._ctx.update(data)
+
+    def finalize(self):
+        if self._ctx is None:
+            raise AlreadyFinalized("Context was already finalized.")
+        data = self._ctx.finalize()
+        self._tag = self._ctx.tag
+        self._ctx = None
+        return data
+
+    def authenticate_additional_data(self, data):
+        if self._ctx is None:
+            raise AlreadyFinalized("Context was already finalized.")
+        if self._updated:
+            raise AlreadyUpdated("Update has been called on this context.")
+
+        self._aad_bytes_processed += len(data)
+        if self._aad_bytes_processed > self._ctx._mode._MAX_AAD_BYTES:
+            raise ValueError(
+                "{0} has a maximum AAD byte limit of {0}".format(
+                    self._ctx._mode.name, self._ctx._mode._MAX_AAD_BYTES
+                )
+            )
+
+        self._ctx.authenticate_additional_data(data)
+
+
+@utils.register_interface(AEADEncryptionContext)
+class _AEADEncryptionContext(_AEADCipherContext):
+    @property
+    def tag(self):
+        if self._ctx is not None:
+            raise NotYetFinalized("You must finalize encryption before "
+                                  "getting the tag.")
+        return self._tag

lib/python3.5/site-packages/cryptography/hazmat/primitives/ciphers/modes.py

@@ -0,0 +1,164 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import abc
+
+import six
+
+from cryptography import utils
+
+
+@six.add_metaclass(abc.ABCMeta)
+class Mode(object):
+    @abc.abstractproperty
+    def name(self):
+        """
+        A string naming this mode (e.g. "ECB", "CBC").
+        """
+
+    @abc.abstractmethod
+    def validate_for_algorithm(self, algorithm):
+        """
+        Checks that all the necessary invariants of this (mode, algorithm)
+        combination are met.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class ModeWithInitializationVector(object):
+    @abc.abstractproperty
+    def initialization_vector(self):
+        """
+        The value of the initialization vector for this mode as bytes.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class ModeWithNonce(object):
+    @abc.abstractproperty
+    def nonce(self):
+        """
+        The value of the nonce for this mode as bytes.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class ModeWithAuthenticationTag(object):
+    @abc.abstractproperty
+    def tag(self):
+        """
+        The value of the tag supplied to the constructor of this mode.
+        """
+
+
+def _check_iv_length(self, algorithm):
+    if len(self.initialization_vector) * 8 != algorithm.block_size:
+        raise ValueError("Invalid IV size ({0}) for {1}.".format(
+            len(self.initialization_vector), self.name
+        ))
+
+
+@utils.register_interface(Mode)
+@utils.register_interface(ModeWithInitializationVector)
+class CBC(object):
+    name = "CBC"
+
+    def __init__(self, initialization_vector):
+        self._initialization_vector = initialization_vector
+
+    initialization_vector = utils.read_only_property("_initialization_vector")
+    validate_for_algorithm = _check_iv_length
+
+
+@utils.register_interface(Mode)
+class ECB(object):
+    name = "ECB"
+
+    def validate_for_algorithm(self, algorithm):
+        pass
+
+
+@utils.register_interface(Mode)
+@utils.register_interface(ModeWithInitializationVector)
+class OFB(object):
+    name = "OFB"
+
+    def __init__(self, initialization_vector):
+        self._initialization_vector = initialization_vector
+
+    initialization_vector = utils.read_only_property("_initialization_vector")
+    validate_for_algorithm = _check_iv_length
+
+
+@utils.register_interface(Mode)
+@utils.register_interface(ModeWithInitializationVector)
+class CFB(object):
+    name = "CFB"
+
+    def __init__(self, initialization_vector):
+        self._initialization_vector = initialization_vector
+
+    initialization_vector = utils.read_only_property("_initialization_vector")
+    validate_for_algorithm = _check_iv_length
+
+
+@utils.register_interface(Mode)
+@utils.register_interface(ModeWithInitializationVector)
+class CFB8(object):
+    name = "CFB8"
+
+    def __init__(self, initialization_vector):
+        self._initialization_vector = initialization_vector
+
+    initialization_vector = utils.read_only_property("_initialization_vector")
+    validate_for_algorithm = _check_iv_length
+
+
+@utils.register_interface(Mode)
+@utils.register_interface(ModeWithNonce)
+class CTR(object):
+    name = "CTR"
+
+    def __init__(self, nonce):
+        self._nonce = nonce
+
+    nonce = utils.read_only_property("_nonce")
+
+    def validate_for_algorithm(self, algorithm):
+        if len(self.nonce) * 8 != algorithm.block_size:
+            raise ValueError("Invalid nonce size ({0}) for {1}.".format(
+                len(self.nonce), self.name
+            ))
+
+
+@utils.register_interface(Mode)
+@utils.register_interface(ModeWithInitializationVector)
+@utils.register_interface(ModeWithAuthenticationTag)
+class GCM(object):
+    name = "GCM"
+    _MAX_ENCRYPTED_BYTES = (2 ** 39 - 256) // 8
+    _MAX_AAD_BYTES = (2 ** 64) // 8
+
+    def __init__(self, initialization_vector, tag=None, min_tag_length=16):
+        # len(initialization_vector) must in [1, 2 ** 64), but it's impossible
+        # to actually construct a bytes object that large, so we don't check
+        # for it
+        if min_tag_length < 4:
+            raise ValueError("min_tag_length must be >= 4")
+        if tag is not None and len(tag) < min_tag_length:
+            raise ValueError(
+                "Authentication tag must be {0} bytes or longer.".format(
+                    min_tag_length)
+            )
+
+        self._initialization_vector = initialization_vector
+        self._tag = tag
+
+    tag = utils.read_only_property("_tag")
+    initialization_vector = utils.read_only_property("_initialization_vector")
+
+    def validate_for_algorithm(self, algorithm):
+        pass

lib/python3.5/site-packages/cryptography/hazmat/primitives/cmac.py

@@ -0,0 +1,66 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+from cryptography import utils
+from cryptography.exceptions import (
+    AlreadyFinalized, UnsupportedAlgorithm, _Reasons
+)
+from cryptography.hazmat.backends.interfaces import CMACBackend
+from cryptography.hazmat.primitives import ciphers, interfaces
+
+
+@utils.register_interface(interfaces.MACContext)
+class CMAC(object):
+    def __init__(self, algorithm, backend, ctx=None):
+        if not isinstance(backend, CMACBackend):
+            raise UnsupportedAlgorithm(
+                "Backend object does not implement CMACBackend.",
+                _Reasons.BACKEND_MISSING_INTERFACE
+            )
+
+        if not isinstance(algorithm, ciphers.BlockCipherAlgorithm):
+            raise TypeError(
+                "Expected instance of BlockCipherAlgorithm."
+            )
+        self._algorithm = algorithm
+
+        self._backend = backend
+        if ctx is None:
+            self._ctx = self._backend.create_cmac_ctx(self._algorithm)
+        else:
+            self._ctx = ctx
+
+    def update(self, data):
+        if self._ctx is None:
+            raise AlreadyFinalized("Context was already finalized.")
+        if not isinstance(data, bytes):
+            raise TypeError("data must be bytes.")
+        self._ctx.update(data)
+
+    def finalize(self):
+        if self._ctx is None:
+            raise AlreadyFinalized("Context was already finalized.")
+        digest = self._ctx.finalize()
+        self._ctx = None
+        return digest
+
+    def verify(self, signature):
+        if not isinstance(signature, bytes):
+            raise TypeError("signature must be bytes.")
+        if self._ctx is None:
+            raise AlreadyFinalized("Context was already finalized.")
+
+        ctx, self._ctx = self._ctx, None
+        ctx.verify(signature)
+
+    def copy(self):
+        if self._ctx is None:
+            raise AlreadyFinalized("Context was already finalized.")
+        return CMAC(
+            self._algorithm,
+            backend=self._backend,
+            ctx=self._ctx.copy()
+        )

lib/python3.5/site-packages/cryptography/hazmat/primitives/constant_time.py

@@ -0,0 +1,26 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import hmac
+
+from cryptography.hazmat.bindings._constant_time import lib
+
+
+if hasattr(hmac, "compare_digest"):
+    def bytes_eq(a, b):
+        if not isinstance(a, bytes) or not isinstance(b, bytes):
+            raise TypeError("a and b must be bytes.")
+
+        return hmac.compare_digest(a, b)
+
+else:
+    def bytes_eq(a, b):
+        if not isinstance(a, bytes) or not isinstance(b, bytes):
+            raise TypeError("a and b must be bytes.")
+
+        return lib.Cryptography_constant_time_bytes_eq(
+            a, len(a), b, len(b)
+        ) == 1

lib/python3.5/site-packages/cryptography/hazmat/primitives/hashes.py

@@ -0,0 +1,163 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import abc
+
+import six
+
+from cryptography import utils
+from cryptography.exceptions import (
+    AlreadyFinalized, UnsupportedAlgorithm, _Reasons
+)
+from cryptography.hazmat.backends.interfaces import HashBackend
+
+
+@six.add_metaclass(abc.ABCMeta)
+class HashAlgorithm(object):
+    @abc.abstractproperty
+    def name(self):
+        """
+        A string naming this algorithm (e.g. "sha256", "md5").
+        """
+
+    @abc.abstractproperty
+    def digest_size(self):
+        """
+        The size of the resulting digest in bytes.
+        """
+
+    @abc.abstractproperty
+    def block_size(self):
+        """
+        The internal block size of the hash algorithm in bytes.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class HashContext(object):
+    @abc.abstractproperty
+    def algorithm(self):
+        """
+        A HashAlgorithm that will be used by this context.
+        """
+
+    @abc.abstractmethod
+    def update(self, data):
+        """
+        Processes the provided bytes through the hash.
+        """
+
+    @abc.abstractmethod
+    def finalize(self):
+        """
+        Finalizes the hash context and returns the hash digest as bytes.
+        """
+
+    @abc.abstractmethod
+    def copy(self):
+        """
+        Return a HashContext that is a copy of the current context.
+        """
+
+
+@utils.register_interface(HashContext)
+class Hash(object):
+    def __init__(self, algorithm, backend, ctx=None):
+        if not isinstance(backend, HashBackend):
+            raise UnsupportedAlgorithm(
+                "Backend object does not implement HashBackend.",
+                _Reasons.BACKEND_MISSING_INTERFACE
+            )
+
+        if not isinstance(algorithm, HashAlgorithm):
+            raise TypeError("Expected instance of hashes.HashAlgorithm.")
+        self._algorithm = algorithm
+
+        self._backend = backend
+
+        if ctx is None:
+            self._ctx = self._backend.create_hash_ctx(self.algorithm)
+        else:
+            self._ctx = ctx
+
+    algorithm = utils.read_only_property("_algorithm")
+
+    def update(self, data):
+        if self._ctx is None:
+            raise AlreadyFinalized("Context was already finalized.")
+        if not isinstance(data, bytes):
+            raise TypeError("data must be bytes.")
+        self._ctx.update(data)
+
+    def copy(self):
+        if self._ctx is None:
+            raise AlreadyFinalized("Context was already finalized.")
+        return Hash(
+            self.algorithm, backend=self._backend, ctx=self._ctx.copy()
+        )
+
+    def finalize(self):
+        if self._ctx is None:
+            raise AlreadyFinalized("Context was already finalized.")
+        digest = self._ctx.finalize()
+        self._ctx = None
+        return digest
+
+
+@utils.register_interface(HashAlgorithm)
+class SHA1(object):
+    name = "sha1"
+    digest_size = 20
+    block_size = 64
+
+
+@utils.register_interface(HashAlgorithm)
+class SHA224(object):
+    name = "sha224"
+    digest_size = 28
+    block_size = 64
+
+
+@utils.register_interface(HashAlgorithm)
+class SHA256(object):
+    name = "sha256"
+    digest_size = 32
+    block_size = 64
+
+
+@utils.register_interface(HashAlgorithm)
+class SHA384(object):
+    name = "sha384"
+    digest_size = 48
+    block_size = 128
+
+
+@utils.register_interface(HashAlgorithm)
+class SHA512(object):
+    name = "sha512"
+    digest_size = 64
+    block_size = 128
+
+
+@utils.register_interface(HashAlgorithm)
+class RIPEMD160(object):
+    name = "ripemd160"
+    digest_size = 20
+    block_size = 64
+
+
+@utils.register_interface(HashAlgorithm)
+class Whirlpool(object):
+    name = "whirlpool"
+    digest_size = 64
+    block_size = 64
+
+
+@utils.register_interface(HashAlgorithm)
+class MD5(object):
+    name = "md5"
+    digest_size = 16
+    block_size = 64

lib/python3.5/site-packages/cryptography/hazmat/primitives/hmac.py

@@ -0,0 +1,69 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+from cryptography import utils
+from cryptography.exceptions import (
+    AlreadyFinalized, UnsupportedAlgorithm, _Reasons
+)
+from cryptography.hazmat.backends.interfaces import HMACBackend
+from cryptography.hazmat.primitives import hashes, interfaces
+
+
+@utils.register_interface(interfaces.MACContext)
+@utils.register_interface(hashes.HashContext)
+class HMAC(object):
+    def __init__(self, key, algorithm, backend, ctx=None):
+        if not isinstance(backend, HMACBackend):
+            raise UnsupportedAlgorithm(
+                "Backend object does not implement HMACBackend.",
+                _Reasons.BACKEND_MISSING_INTERFACE
+            )
+
+        if not isinstance(algorithm, hashes.HashAlgorithm):
+            raise TypeError("Expected instance of hashes.HashAlgorithm.")
+        self._algorithm = algorithm
+
+        self._backend = backend
+        self._key = key
+        if ctx is None:
+            self._ctx = self._backend.create_hmac_ctx(key, self.algorithm)
+        else:
+            self._ctx = ctx
+
+    algorithm = utils.read_only_property("_algorithm")
+
+    def update(self, data):
+        if self._ctx is None:
+            raise AlreadyFinalized("Context was already finalized.")
+        if not isinstance(data, bytes):
+            raise TypeError("data must be bytes.")
+        self._ctx.update(data)
+
+    def copy(self):
+        if self._ctx is None:
+            raise AlreadyFinalized("Context was already finalized.")
+        return HMAC(
+            self._key,
+            self.algorithm,
+            backend=self._backend,
+            ctx=self._ctx.copy()
+        )
+
+    def finalize(self):
+        if self._ctx is None:
+            raise AlreadyFinalized("Context was already finalized.")
+        digest = self._ctx.finalize()
+        self._ctx = None
+        return digest
+
+    def verify(self, signature):
+        if not isinstance(signature, bytes):
+            raise TypeError("signature must be bytes.")
+        if self._ctx is None:
+            raise AlreadyFinalized("Context was already finalized.")
+
+        ctx, self._ctx = self._ctx, None
+        ctx.verify(signature)

lib/python3.5/site-packages/cryptography/hazmat/primitives/interfaces/__init__.py

@@ -0,0 +1,37 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import abc
+
+import six
+
+
+@six.add_metaclass(abc.ABCMeta)
+class MACContext(object):
+    @abc.abstractmethod
+    def update(self, data):
+        """
+        Processes the provided bytes.
+        """
+
+    @abc.abstractmethod
+    def finalize(self):
+        """
+        Returns the message authentication code as bytes.
+        """
+
+    @abc.abstractmethod
+    def copy(self):
+        """
+        Return a MACContext that is a copy of the current context.
+        """
+
+    @abc.abstractmethod
+    def verify(self, signature):
+        """
+        Checks if the generated message authentication code matches the
+        signature.
+        """

lib/python3.5/site-packages/cryptography/hazmat/primitives/kdf/__init__.py

@@ -0,0 +1,26 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import abc
+
+import six
+
+
+@six.add_metaclass(abc.ABCMeta)
+class KeyDerivationFunction(object):
+    @abc.abstractmethod
+    def derive(self, key_material):
+        """
+        Deterministically generates and returns a new key based on the existing
+        key material.
+        """
+
+    @abc.abstractmethod
+    def verify(self, key_material, expected_key):
+        """
+        Checks whether the key generated by the key material matches the
+        expected derived key. Raises an exception if they do not match.
+        """

lib/python3.5/site-packages/cryptography/hazmat/primitives/kdf/concatkdf.py

@@ -0,0 +1,125 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import struct
+
+from cryptography import utils
+from cryptography.exceptions import (
+    AlreadyFinalized, InvalidKey, UnsupportedAlgorithm, _Reasons
+)
+from cryptography.hazmat.backends.interfaces import HMACBackend
+from cryptography.hazmat.backends.interfaces import HashBackend
+from cryptography.hazmat.primitives import constant_time, hashes, hmac
+from cryptography.hazmat.primitives.kdf import KeyDerivationFunction
+
+
+def _int_to_u32be(n):
+    return struct.pack('>I', n)
+
+
+def _common_args_checks(algorithm, length, otherinfo):
+    max_length = algorithm.digest_size * (2 ** 32 - 1)
+    if length > max_length:
+        raise ValueError(
+            "Can not derive keys larger than {0} bits.".format(
+                max_length
+            ))
+    if not (otherinfo is None or isinstance(otherinfo, bytes)):
+        raise TypeError("otherinfo must be bytes.")
+
+
+def _concatkdf_derive(key_material, length, auxfn, otherinfo):
+    if not isinstance(key_material, bytes):
+        raise TypeError("key_material must be bytes.")
+
+    output = [b""]
+    outlen = 0
+    counter = 1
+
+    while (length > outlen):
+        h = auxfn()
+        h.update(_int_to_u32be(counter))
+        h.update(key_material)
+        h.update(otherinfo)
+        output.append(h.finalize())
+        outlen += len(output[-1])
+        counter += 1
+
+    return b"".join(output)[:length]
+
+
+@utils.register_interface(KeyDerivationFunction)
+class ConcatKDFHash(object):
+    def __init__(self, algorithm, length, otherinfo, backend):
+
+        _common_args_checks(algorithm, length, otherinfo)
+        self._algorithm = algorithm
+        self._length = length
+        self._otherinfo = otherinfo
+        if self._otherinfo is None:
+            self._otherinfo = b""
+
+        if not isinstance(backend, HashBackend):
+            raise UnsupportedAlgorithm(
+                "Backend object does not implement HashBackend.",
+                _Reasons.BACKEND_MISSING_INTERFACE
+            )
+        self._backend = backend
+        self._used = False
+
+    def _hash(self):
+        return hashes.Hash(self._algorithm, self._backend)
+
+    def derive(self, key_material):
+        if self._used:
+            raise AlreadyFinalized
+        self._used = True
+        return _concatkdf_derive(key_material, self._length,
+                                 self._hash, self._otherinfo)
+
+    def verify(self, key_material, expected_key):
+        if not constant_time.bytes_eq(self.derive(key_material), expected_key):
+            raise InvalidKey
+
+
+@utils.register_interface(KeyDerivationFunction)
+class ConcatKDFHMAC(object):
+    def __init__(self, algorithm, length, salt, otherinfo, backend):
+
+        _common_args_checks(algorithm, length, otherinfo)
+        self._algorithm = algorithm
+        self._length = length
+        self._otherinfo = otherinfo
+        if self._otherinfo is None:
+            self._otherinfo = b""
+
+        if not (salt is None or isinstance(salt, bytes)):
+            raise TypeError("salt must be bytes.")
+        if salt is None:
+            salt = b"\x00" * algorithm.block_size
+        self._salt = salt
+
+        if not isinstance(backend, HMACBackend):
+            raise UnsupportedAlgorithm(
+                "Backend object does not implement HMACBackend.",
+                _Reasons.BACKEND_MISSING_INTERFACE
+            )
+        self._backend = backend
+        self._used = False
+
+    def _hmac(self):
+        return hmac.HMAC(self._salt, self._algorithm, self._backend)
+
+    def derive(self, key_material):
+        if self._used:
+            raise AlreadyFinalized
+        self._used = True
+        return _concatkdf_derive(key_material, self._length,
+                                 self._hmac, self._otherinfo)
+
+    def verify(self, key_material, expected_key):
+        if not constant_time.bytes_eq(self.derive(key_material), expected_key):
+            raise InvalidKey

lib/python3.5/site-packages/cryptography/hazmat/primitives/kdf/hkdf.py

@@ -0,0 +1,116 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import six
+
+from cryptography import utils
+from cryptography.exceptions import (
+    AlreadyFinalized, InvalidKey, UnsupportedAlgorithm, _Reasons
+)
+from cryptography.hazmat.backends.interfaces import HMACBackend
+from cryptography.hazmat.primitives import constant_time, hmac
+from cryptography.hazmat.primitives.kdf import KeyDerivationFunction
+
+
+@utils.register_interface(KeyDerivationFunction)
+class HKDF(object):
+    def __init__(self, algorithm, length, salt, info, backend):
+        if not isinstance(backend, HMACBackend):
+            raise UnsupportedAlgorithm(
+                "Backend object does not implement HMACBackend.",
+                _Reasons.BACKEND_MISSING_INTERFACE
+            )
+
+        self._algorithm = algorithm
+
+        if not (salt is None or isinstance(salt, bytes)):
+            raise TypeError("salt must be bytes.")
+
+        if salt is None:
+            salt = b"\x00" * (self._algorithm.digest_size // 8)
+
+        self._salt = salt
+
+        self._backend = backend
+
+        self._hkdf_expand = HKDFExpand(self._algorithm, length, info, backend)
+
+    def _extract(self, key_material):
+        h = hmac.HMAC(self._salt, self._algorithm, backend=self._backend)
+        h.update(key_material)
+        return h.finalize()
+
+    def derive(self, key_material):
+        if not isinstance(key_material, bytes):
+            raise TypeError("key_material must be bytes.")
+
+        return self._hkdf_expand.derive(self._extract(key_material))
+
+    def verify(self, key_material, expected_key):
+        if not constant_time.bytes_eq(self.derive(key_material), expected_key):
+            raise InvalidKey
+
+
+@utils.register_interface(KeyDerivationFunction)
+class HKDFExpand(object):
+    def __init__(self, algorithm, length, info, backend):
+        if not isinstance(backend, HMACBackend):
+            raise UnsupportedAlgorithm(
+                "Backend object does not implement HMACBackend.",
+                _Reasons.BACKEND_MISSING_INTERFACE
+            )
+
+        self._algorithm = algorithm
+
+        self._backend = backend
+
+        max_length = 255 * (algorithm.digest_size // 8)
+
+        if length > max_length:
+            raise ValueError(
+                "Can not derive keys larger than {0} octets.".format(
+                    max_length
+                ))
+
+        self._length = length
+
+        if not (info is None or isinstance(info, bytes)):
+            raise TypeError("info must be bytes.")
+
+        if info is None:
+            info = b""
+
+        self._info = info
+
+        self._used = False
+
+    def _expand(self, key_material):
+        output = [b""]
+        counter = 1
+
+        while (self._algorithm.digest_size // 8) * len(output) < self._length:
+            h = hmac.HMAC(key_material, self._algorithm, backend=self._backend)
+            h.update(output[-1])
+            h.update(self._info)
+            h.update(six.int2byte(counter))
+            output.append(h.finalize())
+            counter += 1
+
+        return b"".join(output)[:self._length]
+
+    def derive(self, key_material):
+        if not isinstance(key_material, bytes):
+            raise TypeError("key_material must be bytes.")
+
+        if self._used:
+            raise AlreadyFinalized
+
+        self._used = True
+        return self._expand(key_material)
+
+    def verify(self, key_material, expected_key):
+        if not constant_time.bytes_eq(self.derive(key_material), expected_key):
+            raise InvalidKey

lib/python3.5/site-packages/cryptography/hazmat/primitives/kdf/pbkdf2.py

@@ -0,0 +1,58 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+from cryptography import utils
+from cryptography.exceptions import (
+    AlreadyFinalized, InvalidKey, UnsupportedAlgorithm, _Reasons
+)
+from cryptography.hazmat.backends.interfaces import PBKDF2HMACBackend
+from cryptography.hazmat.primitives import constant_time
+from cryptography.hazmat.primitives.kdf import KeyDerivationFunction
+
+
+@utils.register_interface(KeyDerivationFunction)
+class PBKDF2HMAC(object):
+    def __init__(self, algorithm, length, salt, iterations, backend):
+        if not isinstance(backend, PBKDF2HMACBackend):
+            raise UnsupportedAlgorithm(
+                "Backend object does not implement PBKDF2HMACBackend.",
+                _Reasons.BACKEND_MISSING_INTERFACE
+            )
+
+        if not backend.pbkdf2_hmac_supported(algorithm):
+            raise UnsupportedAlgorithm(
+                "{0} is not supported for PBKDF2 by this backend.".format(
+                    algorithm.name),
+                _Reasons.UNSUPPORTED_HASH
+            )
+        self._used = False
+        self._algorithm = algorithm
+        self._length = length
+        if not isinstance(salt, bytes):
+            raise TypeError("salt must be bytes.")
+        self._salt = salt
+        self._iterations = iterations
+        self._backend = backend
+
+    def derive(self, key_material):
+        if self._used:
+            raise AlreadyFinalized("PBKDF2 instances can only be used once.")
+        self._used = True
+
+        if not isinstance(key_material, bytes):
+            raise TypeError("key_material must be bytes.")
+        return self._backend.derive_pbkdf2_hmac(
+            self._algorithm,
+            self._length,
+            self._salt,
+            self._iterations,
+            key_material
+        )
+
+    def verify(self, key_material, expected_key):
+        derived_key = self.derive(key_material)
+        if not constant_time.bytes_eq(derived_key, expected_key):
+            raise InvalidKey("Keys do not match.")

lib/python3.5/site-packages/cryptography/hazmat/primitives/kdf/x963kdf.py

@@ -0,0 +1,70 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import struct
+
+from cryptography import utils
+from cryptography.exceptions import (
+    AlreadyFinalized, InvalidKey, UnsupportedAlgorithm, _Reasons
+)
+from cryptography.hazmat.backends.interfaces import HashBackend
+from cryptography.hazmat.primitives import constant_time, hashes
+from cryptography.hazmat.primitives.kdf import KeyDerivationFunction
+
+
+def _int_to_u32be(n):
+    return struct.pack('>I', n)
+
+
+@utils.register_interface(KeyDerivationFunction)
+class X963KDF(object):
+    def __init__(self, algorithm, length, sharedinfo, backend):
+
+        max_len = algorithm.digest_size * (2 ** 32 - 1)
+        if length > max_len:
+            raise ValueError(
+                "Can not derive keys larger than {0} bits.".format(max_len))
+        if not (sharedinfo is None or isinstance(sharedinfo, bytes)):
+            raise TypeError("sharedinfo must be bytes.")
+        self._algorithm = algorithm
+        self._length = length
+        self._sharedinfo = sharedinfo
+
+        if not isinstance(backend, HashBackend):
+            raise UnsupportedAlgorithm(
+                "Backend object does not implement HashBackend.",
+                _Reasons.BACKEND_MISSING_INTERFACE
+            )
+        self._backend = backend
+        self._used = False
+
+    def derive(self, key_material):
+        if self._used:
+            raise AlreadyFinalized
+        self._used = True
+
+        if not isinstance(key_material, bytes):
+            raise TypeError("key_material must be bytes.")
+
+        output = [b""]
+        outlen = 0
+        counter = 1
+
+        while self._length > outlen:
+            h = hashes.Hash(self._algorithm, self._backend)
+            h.update(key_material)
+            h.update(_int_to_u32be(counter))
+            if self._sharedinfo is not None:
+                h.update(self._sharedinfo)
+            output.append(h.finalize())
+            outlen += len(output[-1])
+            counter += 1
+
+        return b"".join(output)[:self._length]
+
+    def verify(self, key_material, expected_key):
+        if not constant_time.bytes_eq(self.derive(key_material), expected_key):
+            raise InvalidKey

lib/python3.5/site-packages/cryptography/hazmat/primitives/keywrap.py

@@ -0,0 +1,85 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import struct
+
+from cryptography.hazmat.primitives.ciphers import Cipher
+from cryptography.hazmat.primitives.ciphers.algorithms import AES
+from cryptography.hazmat.primitives.ciphers.modes import ECB
+from cryptography.hazmat.primitives.constant_time import bytes_eq
+
+
+def aes_key_wrap(wrapping_key, key_to_wrap, backend):
+    if len(wrapping_key) not in [16, 24, 32]:
+        raise ValueError("The wrapping key must be a valid AES key length")
+
+    if len(key_to_wrap) < 16:
+        raise ValueError("The key to wrap must be at least 16 bytes")
+
+    if len(key_to_wrap) % 8 != 0:
+        raise ValueError("The key to wrap must be a multiple of 8 bytes")
+
+    # RFC 3394 Key Wrap - 2.2.1 (index method)
+    encryptor = Cipher(AES(wrapping_key), ECB(), backend).encryptor()
+    a = b"\xa6\xa6\xa6\xa6\xa6\xa6\xa6\xa6"
+    r = [key_to_wrap[i:i + 8] for i in range(0, len(key_to_wrap), 8)]
+    n = len(r)
+    for j in range(6):
+        for i in range(n):
+            # every encryption operation is a discrete 16 byte chunk (because
+            # AES has a 128-bit block size) and since we're using ECB it is
+            # safe to reuse the encryptor for the entire operation
+            b = encryptor.update(a + r[i])
+            # pack/unpack are safe as these are always 64-bit chunks
+            a = struct.pack(
+                ">Q", struct.unpack(">Q", b[:8])[0] ^ ((n * j) + i + 1)
+            )
+            r[i] = b[-8:]
+
+    assert encryptor.finalize() == b""
+
+    return a + b"".join(r)
+
+
+def aes_key_unwrap(wrapping_key, wrapped_key, backend):
+    if len(wrapped_key) < 24:
+        raise ValueError("Must be at least 24 bytes")
+
+    if len(wrapped_key) % 8 != 0:
+        raise ValueError("The wrapped key must be a multiple of 8 bytes")
+
+    if len(wrapping_key) not in [16, 24, 32]:
+        raise ValueError("The wrapping key must be a valid AES key length")
+
+    # Implement RFC 3394 Key Unwrap - 2.2.2 (index method)
+    decryptor = Cipher(AES(wrapping_key), ECB(), backend).decryptor()
+    aiv = b"\xa6\xa6\xa6\xa6\xa6\xa6\xa6\xa6"
+
+    r = [wrapped_key[i:i + 8] for i in range(0, len(wrapped_key), 8)]
+    a = r.pop(0)
+    n = len(r)
+    for j in reversed(range(6)):
+        for i in reversed(range(n)):
+            # pack/unpack are safe as these are always 64-bit chunks
+            atr = struct.pack(
+                ">Q", struct.unpack(">Q", a)[0] ^ ((n * j) + i + 1)
+            ) + r[i]
+            # every decryption operation is a discrete 16 byte chunk so
+            # it is safe to reuse the decryptor for the entire operation
+            b = decryptor.update(atr)
+            a = b[:8]
+            r[i] = b[-8:]
+
+    assert decryptor.finalize() == b""
+
+    if not bytes_eq(a, aiv):
+        raise InvalidUnwrap()
+
+    return b"".join(r)
+
+
+class InvalidUnwrap(Exception):
+    pass

lib/python3.5/site-packages/cryptography/hazmat/primitives/padding.py

@@ -0,0 +1,124 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import abc
+
+import six
+
+from cryptography import utils
+from cryptography.exceptions import AlreadyFinalized
+from cryptography.hazmat.bindings._padding import lib
+
+
+@six.add_metaclass(abc.ABCMeta)
+class PaddingContext(object):
+    @abc.abstractmethod
+    def update(self, data):
+        """
+        Pads the provided bytes and returns any available data as bytes.
+        """
+
+    @abc.abstractmethod
+    def finalize(self):
+        """
+        Finalize the padding, returns bytes.
+        """
+
+
+class PKCS7(object):
+    def __init__(self, block_size):
+        if not (0 <= block_size < 256):
+            raise ValueError("block_size must be in range(0, 256).")
+
+        if block_size % 8 != 0:
+            raise ValueError("block_size must be a multiple of 8.")
+
+        self.block_size = block_size
+
+    def padder(self):
+        return _PKCS7PaddingContext(self.block_size)
+
+    def unpadder(self):
+        return _PKCS7UnpaddingContext(self.block_size)
+
+
+@utils.register_interface(PaddingContext)
+class _PKCS7PaddingContext(object):
+    def __init__(self, block_size):
+        self.block_size = block_size
+        # TODO: more copies than necessary, we should use zero-buffer (#193)
+        self._buffer = b""
+
+    def update(self, data):
+        if self._buffer is None:
+            raise AlreadyFinalized("Context was already finalized.")
+
+        if not isinstance(data, bytes):
+            raise TypeError("data must be bytes.")
+
+        self._buffer += data
+
+        finished_blocks = len(self._buffer) // (self.block_size // 8)
+
+        result = self._buffer[:finished_blocks * (self.block_size // 8)]
+        self._buffer = self._buffer[finished_blocks * (self.block_size // 8):]
+
+        return result
+
+    def finalize(self):
+        if self._buffer is None:
+            raise AlreadyFinalized("Context was already finalized.")
+
+        pad_size = self.block_size // 8 - len(self._buffer)
+        result = self._buffer + six.int2byte(pad_size) * pad_size
+        self._buffer = None
+        return result
+
+
+@utils.register_interface(PaddingContext)
+class _PKCS7UnpaddingContext(object):
+    def __init__(self, block_size):
+        self.block_size = block_size
+        # TODO: more copies than necessary, we should use zero-buffer (#193)
+        self._buffer = b""
+
+    def update(self, data):
+        if self._buffer is None:
+            raise AlreadyFinalized("Context was already finalized.")
+
+        if not isinstance(data, bytes):
+            raise TypeError("data must be bytes.")
+
+        self._buffer += data
+
+        finished_blocks = max(
+            len(self._buffer) // (self.block_size // 8) - 1,
+            0
+        )
+
+        result = self._buffer[:finished_blocks * (self.block_size // 8)]
+        self._buffer = self._buffer[finished_blocks * (self.block_size // 8):]
+
+        return result
+
+    def finalize(self):
+        if self._buffer is None:
+            raise AlreadyFinalized("Context was already finalized.")
+
+        if len(self._buffer) != self.block_size // 8:
+            raise ValueError("Invalid padding bytes.")
+
+        valid = lib.Cryptography_check_pkcs7_padding(
+            self._buffer, self.block_size // 8
+        )
+
+        if not valid:
+            raise ValueError("Invalid padding bytes.")
+
+        pad_size = six.indexbytes(self._buffer, -1)
+        res = self._buffer[:-pad_size]
+        self._buffer = None
+        return res

lib/python3.5/site-packages/cryptography/hazmat/primitives/serialization.py

@@ -0,0 +1,188 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import abc
+import base64
+import struct
+from enum import Enum
+
+import six
+
+from cryptography import utils
+from cryptography.exceptions import UnsupportedAlgorithm
+from cryptography.hazmat.primitives.asymmetric import dsa, ec, rsa
+
+
+def load_pem_private_key(data, password, backend):
+    return backend.load_pem_private_key(data, password)
+
+
+def load_pem_public_key(data, backend):
+    return backend.load_pem_public_key(data)
+
+
+def load_der_private_key(data, password, backend):
+    return backend.load_der_private_key(data, password)
+
+
+def load_der_public_key(data, backend):
+    return backend.load_der_public_key(data)
+
+
+def load_ssh_public_key(data, backend):
+    key_parts = data.split(b' ', 2)
+
+    if len(key_parts) < 2:
+        raise ValueError(
+            'Key is not in the proper format or contains extra data.')
+
+    key_type = key_parts[0]
+
+    if key_type == b'ssh-rsa':
+        loader = _load_ssh_rsa_public_key
+    elif key_type == b'ssh-dss':
+        loader = _load_ssh_dss_public_key
+    elif key_type in [
+        b'ecdsa-sha2-nistp256', b'ecdsa-sha2-nistp384', b'ecdsa-sha2-nistp521',
+    ]:
+        loader = _load_ssh_ecdsa_public_key
+    else:
+        raise UnsupportedAlgorithm('Key type is not supported.')
+
+    key_body = key_parts[1]
+
+    try:
+        decoded_data = base64.b64decode(key_body)
+    except TypeError:
+        raise ValueError('Key is not in the proper format.')
+
+    inner_key_type, rest = _read_next_string(decoded_data)
+
+    if inner_key_type != key_type:
+        raise ValueError(
+            'Key header and key body contain different key type values.'
+        )
+
+    return loader(key_type, rest, backend)
+
+
+def _load_ssh_rsa_public_key(key_type, decoded_data, backend):
+    e, rest = _read_next_mpint(decoded_data)
+    n, rest = _read_next_mpint(rest)
+
+    if rest:
+        raise ValueError('Key body contains extra bytes.')
+
+    return rsa.RSAPublicNumbers(e, n).public_key(backend)
+
+
+def _load_ssh_dss_public_key(key_type, decoded_data, backend):
+    p, rest = _read_next_mpint(decoded_data)
+    q, rest = _read_next_mpint(rest)
+    g, rest = _read_next_mpint(rest)
+    y, rest = _read_next_mpint(rest)
+
+    if rest:
+        raise ValueError('Key body contains extra bytes.')
+
+    parameter_numbers = dsa.DSAParameterNumbers(p, q, g)
+    public_numbers = dsa.DSAPublicNumbers(y, parameter_numbers)
+
+    return public_numbers.public_key(backend)
+
+
+def _load_ssh_ecdsa_public_key(expected_key_type, decoded_data, backend):
+    curve_name, rest = _read_next_string(decoded_data)
+    data, rest = _read_next_string(rest)
+
+    if expected_key_type != b"ecdsa-sha2-" + curve_name:
+        raise ValueError(
+            'Key header and key body contain different key type values.'
+        )
+
+    if rest:
+        raise ValueError('Key body contains extra bytes.')
+
+    curve = {
+        b"nistp256": ec.SECP256R1,
+        b"nistp384": ec.SECP384R1,
+        b"nistp521": ec.SECP521R1,
+    }[curve_name]()
+
+    if six.indexbytes(data, 0) != 4:
+        raise NotImplementedError(
+            "Compressed elliptic curve points are not supported"
+        )
+
+    # key_size is in bits, and sometimes it's not evenly divisible by 8, so we
+    # add 7 to round up the number of bytes.
+    if len(data) != 1 + 2 * ((curve.key_size + 7) // 8):
+        raise ValueError("Malformed key bytes")
+
+    x = utils.int_from_bytes(
+        data[1:1 + (curve.key_size + 7) // 8], byteorder='big'
+    )
+    y = utils.int_from_bytes(
+        data[1 + (curve.key_size + 7) // 8:], byteorder='big'
+    )
+    return ec.EllipticCurvePublicNumbers(x, y, curve).public_key(backend)
+
+
+def _read_next_string(data):
+    """
+    Retrieves the next RFC 4251 string value from the data.
+
+    While the RFC calls these strings, in Python they are bytes objects.
+    """
+    str_len, = struct.unpack('>I', data[:4])
+    return data[4:4 + str_len], data[4 + str_len:]
+
+
+def _read_next_mpint(data):
+    """
+    Reads the next mpint from the data.
+
+    Currently, all mpints are interpreted as unsigned.
+    """
+    mpint_data, rest = _read_next_string(data)
+
+    return (
+        utils.int_from_bytes(mpint_data, byteorder='big', signed=False), rest
+    )
+
+
+class Encoding(Enum):
+    PEM = "PEM"
+    DER = "DER"
+
+
+class PrivateFormat(Enum):
+    PKCS8 = "PKCS8"
+    TraditionalOpenSSL = "TraditionalOpenSSL"
+
+
+class PublicFormat(Enum):
+    SubjectPublicKeyInfo = "X.509 subjectPublicKeyInfo with PKCS#1"
+    PKCS1 = "Raw PKCS#1"
+
+
+@six.add_metaclass(abc.ABCMeta)
+class KeySerializationEncryption(object):
+    pass
+
+
+@utils.register_interface(KeySerializationEncryption)
+class BestAvailableEncryption(object):
+    def __init__(self, password):
+        if not isinstance(password, bytes) or len(password) == 0:
+            raise ValueError("Password must be 1 or more bytes.")
+
+        self.password = password
+
+
+@utils.register_interface(KeySerializationEncryption)
+class NoEncryption(object):
+    pass

lib/python3.5/site-packages/cryptography/hazmat/primitives/twofactor/__init__.py

@@ -0,0 +1,9 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+
+class InvalidToken(Exception):
+    pass

lib/python3.5/site-packages/cryptography/hazmat/primitives/twofactor/hotp.py

@@ -0,0 +1,67 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import struct
+
+import six
+
+from cryptography.exceptions import (
+    UnsupportedAlgorithm, _Reasons
+)
+from cryptography.hazmat.backends.interfaces import HMACBackend
+from cryptography.hazmat.primitives import constant_time, hmac
+from cryptography.hazmat.primitives.hashes import SHA1, SHA256, SHA512
+from cryptography.hazmat.primitives.twofactor import InvalidToken
+from cryptography.hazmat.primitives.twofactor.utils import _generate_uri
+
+
+class HOTP(object):
+    def __init__(self, key, length, algorithm, backend):
+        if not isinstance(backend, HMACBackend):
+            raise UnsupportedAlgorithm(
+                "Backend object does not implement HMACBackend.",
+                _Reasons.BACKEND_MISSING_INTERFACE
+            )
+
+        if len(key) < 16:
+            raise ValueError("Key length has to be at least 128 bits.")
+
+        if not isinstance(length, six.integer_types):
+            raise TypeError("Length parameter must be an integer type.")
+
+        if length < 6 or length > 8:
+            raise ValueError("Length of HOTP has to be between 6 to 8.")
+
+        if not isinstance(algorithm, (SHA1, SHA256, SHA512)):
+            raise TypeError("Algorithm must be SHA1, SHA256 or SHA512.")
+
+        self._key = key
+        self._length = length
+        self._algorithm = algorithm
+        self._backend = backend
+
+    def generate(self, counter):
+        truncated_value = self._dynamic_truncate(counter)
+        hotp = truncated_value % (10 ** self._length)
+        return "{0:0{1}}".format(hotp, self._length).encode()
+
+    def verify(self, hotp, counter):
+        if not constant_time.bytes_eq(self.generate(counter), hotp):
+            raise InvalidToken("Supplied HOTP value does not match.")
+
+    def _dynamic_truncate(self, counter):
+        ctx = hmac.HMAC(self._key, self._algorithm, self._backend)
+        ctx.update(struct.pack(">Q", counter))
+        hmac_value = ctx.finalize()
+
+        offset = six.indexbytes(hmac_value, len(hmac_value) - 1) & 0b1111
+        p = hmac_value[offset:offset + 4]
+        return struct.unpack(">I", p)[0] & 0x7fffffff
+
+    def get_provisioning_uri(self, account_name, counter, issuer):
+        return _generate_uri(self, "hotp", account_name, issuer, [
+            ("counter", int(counter)),
+        ])

lib/python3.5/site-packages/cryptography/hazmat/primitives/twofactor/totp.py

@@ -0,0 +1,39 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+from cryptography.exceptions import (
+    UnsupportedAlgorithm, _Reasons
+)
+from cryptography.hazmat.backends.interfaces import HMACBackend
+from cryptography.hazmat.primitives import constant_time
+from cryptography.hazmat.primitives.twofactor import InvalidToken
+from cryptography.hazmat.primitives.twofactor.hotp import HOTP
+from cryptography.hazmat.primitives.twofactor.utils import _generate_uri
+
+
+class TOTP(object):
+    def __init__(self, key, length, algorithm, time_step, backend):
+        if not isinstance(backend, HMACBackend):
+            raise UnsupportedAlgorithm(
+                "Backend object does not implement HMACBackend.",
+                _Reasons.BACKEND_MISSING_INTERFACE
+            )
+
+        self._time_step = time_step
+        self._hotp = HOTP(key, length, algorithm, backend)
+
+    def generate(self, time):
+        counter = int(time / self._time_step)
+        return self._hotp.generate(counter)
+
+    def verify(self, totp, time):
+        if not constant_time.bytes_eq(self.generate(time), totp):
+            raise InvalidToken("Supplied TOTP value does not match.")
+
+    def get_provisioning_uri(self, account_name, issuer):
+        return _generate_uri(self._hotp, "totp", account_name, issuer, [
+            ("period", int(self._time_step)),
+        ])

lib/python3.5/site-packages/cryptography/hazmat/primitives/twofactor/utils.py

@@ -0,0 +1,30 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import base64
+
+from six.moves.urllib.parse import quote, urlencode
+
+
+def _generate_uri(hotp, type_name, account_name, issuer, extra_parameters):
+    parameters = [
+        ("digits", hotp._length),
+        ("secret", base64.b32encode(hotp._key)),
+        ("algorithm", hotp._algorithm.name.upper()),
+    ]
+
+    if issuer is not None:
+        parameters.append(("issuer", issuer))
+
+    parameters.extend(extra_parameters)
+
+    uriparts = {
+        "type": type_name,
+        "label": ("%s:%s" % (quote(issuer), quote(account_name)) if issuer
+                  else quote(account_name)),
+        "parameters": urlencode(parameters),
+    }
+    return "otpauth://{type}/{label}?{parameters}".format(**uriparts)

lib/python3.5/site-packages/cryptography/utils.py

@@ -0,0 +1,127 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import abc
+import binascii
+import inspect
+import struct
+import sys
+import warnings
+
+
+DeprecatedIn09 = DeprecationWarning
+DeprecatedIn10 = PendingDeprecationWarning
+
+
+def read_only_property(name):
+    return property(lambda self: getattr(self, name))
+
+
+def register_interface(iface):
+    def register_decorator(klass):
+        verify_interface(iface, klass)
+        iface.register(klass)
+        return klass
+    return register_decorator
+
+
+if hasattr(int, "from_bytes"):
+    int_from_bytes = int.from_bytes
+else:
+    def int_from_bytes(data, byteorder, signed=False):
+        assert byteorder == 'big'
+        assert not signed
+
+        if len(data) % 4 != 0:
+            data = (b'\x00' * (4 - (len(data) % 4))) + data
+
+        result = 0
+
+        while len(data) > 0:
+            digit, = struct.unpack('>I', data[:4])
+            result = (result << 32) + digit
+            data = data[4:]
+
+        return result
+
+
+def int_to_bytes(integer, length=None):
+    hex_string = '%x' % integer
+    if length is None:
+        n = len(hex_string)
+    else:
+        n = length * 2
+    return binascii.unhexlify(hex_string.zfill(n + (n & 1)))
+
+
+class InterfaceNotImplemented(Exception):
+    pass
+
+
+if hasattr(inspect, "signature"):
+    signature = inspect.signature
+else:
+    signature = inspect.getargspec
+
+
+def verify_interface(iface, klass):
+    for method in iface.__abstractmethods__:
+        if not hasattr(klass, method):
+            raise InterfaceNotImplemented(
+                "{0} is missing a {1!r} method".format(klass, method)
+            )
+        if isinstance(getattr(iface, method), abc.abstractproperty):
+            # Can't properly verify these yet.
+            continue
+        sig = signature(getattr(iface, method))
+        actual = signature(getattr(klass, method))
+        if sig != actual:
+            raise InterfaceNotImplemented(
+                "{0}.{1}'s signature differs from the expected. Expected: "
+                "{2!r}. Received: {3!r}".format(
+                    klass, method, sig, actual
+                )
+            )
+
+
+if sys.version_info >= (2, 7):
+    def bit_length(x):
+        return x.bit_length()
+else:
+    def bit_length(x):
+        return len(bin(x)) - (2 + (x <= 0))
+
+
+class _DeprecatedValue(object):
+    def __init__(self, value, message, warning_class):
+        self.value = value
+        self.message = message
+        self.warning_class = warning_class
+
+
+class _ModuleWithDeprecations(object):
+    def __init__(self, module):
+        self.__dict__["_module"] = module
+
+    def __getattr__(self, attr):
+        obj = getattr(self._module, attr)
+        if isinstance(obj, _DeprecatedValue):
+            warnings.warn(obj.message, obj.warning_class, stacklevel=2)
+            obj = obj.value
+        return obj
+
+    def __setattr__(self, attr, value):
+        setattr(self._module, attr, value)
+
+    def __dir__(self):
+        return ["_module"] + dir(self._module)
+
+
+def deprecated(value, module_name, message, warning_class):
+    module = sys.modules[module_name]
+    if not isinstance(module, _ModuleWithDeprecations):
+        sys.modules[module_name] = module = _ModuleWithDeprecations(module)
+    return _DeprecatedValue(value, message, warning_class)

lib/python3.5/site-packages/cryptography/x509/__init__.py

@@ -0,0 +1,163 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+from cryptography.x509.base import (
+    Certificate, CertificateBuilder, CertificateRevocationList,
+    CertificateSigningRequest, CertificateSigningRequestBuilder,
+    InvalidVersion, RevokedCertificate,
+    Version, load_der_x509_certificate, load_der_x509_crl, load_der_x509_csr,
+    load_pem_x509_certificate, load_pem_x509_crl, load_pem_x509_csr,
+)
+from cryptography.x509.extensions import (
+    AccessDescription, AuthorityInformationAccess,
+    AuthorityKeyIdentifier, BasicConstraints, CRLDistributionPoints,
+    CertificatePolicies, DistributionPoint, DuplicateExtension,
+    ExtendedKeyUsage, Extension, ExtensionNotFound, ExtensionType, Extensions,
+    GeneralNames, InhibitAnyPolicy, IssuerAlternativeName, KeyUsage,
+    NameConstraints, NoticeReference, OCSPNoCheck, PolicyInformation,
+    ReasonFlags, SubjectAlternativeName, SubjectKeyIdentifier,
+    UnsupportedExtension, UserNotice
+)
+from cryptography.x509.general_name import (
+    DNSName, DirectoryName, GeneralName, IPAddress, OtherName, RFC822Name,
+    RegisteredID, UniformResourceIdentifier, UnsupportedGeneralNameType,
+    _GENERAL_NAMES
+)
+from cryptography.x509.name import Name, NameAttribute
+from cryptography.x509.oid import (
+    AuthorityInformationAccessOID, CRLExtensionOID, CertificatePoliciesOID,
+    ExtendedKeyUsageOID, ExtensionOID, NameOID, ObjectIdentifier,
+    SignatureAlgorithmOID, _SIG_OIDS_TO_HASH
+)
+
+
+OID_AUTHORITY_INFORMATION_ACCESS = ExtensionOID.AUTHORITY_INFORMATION_ACCESS
+OID_AUTHORITY_KEY_IDENTIFIER = ExtensionOID.AUTHORITY_KEY_IDENTIFIER
+OID_BASIC_CONSTRAINTS = ExtensionOID.BASIC_CONSTRAINTS
+OID_CERTIFICATE_POLICIES = ExtensionOID.CERTIFICATE_POLICIES
+OID_CRL_DISTRIBUTION_POINTS = ExtensionOID.CRL_DISTRIBUTION_POINTS
+OID_EXTENDED_KEY_USAGE = ExtensionOID.EXTENDED_KEY_USAGE
+OID_FRESHEST_CRL = ExtensionOID.FRESHEST_CRL
+OID_INHIBIT_ANY_POLICY = ExtensionOID.INHIBIT_ANY_POLICY
+OID_ISSUER_ALTERNATIVE_NAME = ExtensionOID.ISSUER_ALTERNATIVE_NAME
+OID_KEY_USAGE = ExtensionOID.KEY_USAGE
+OID_NAME_CONSTRAINTS = ExtensionOID.NAME_CONSTRAINTS
+OID_OCSP_NO_CHECK = ExtensionOID.OCSP_NO_CHECK
+OID_POLICY_CONSTRAINTS = ExtensionOID.POLICY_CONSTRAINTS
+OID_POLICY_MAPPINGS = ExtensionOID.POLICY_MAPPINGS
+OID_SUBJECT_ALTERNATIVE_NAME = ExtensionOID.SUBJECT_ALTERNATIVE_NAME
+OID_SUBJECT_DIRECTORY_ATTRIBUTES = ExtensionOID.SUBJECT_DIRECTORY_ATTRIBUTES
+OID_SUBJECT_INFORMATION_ACCESS = ExtensionOID.SUBJECT_INFORMATION_ACCESS
+OID_SUBJECT_KEY_IDENTIFIER = ExtensionOID.SUBJECT_KEY_IDENTIFIER
+
+OID_DSA_WITH_SHA1 = SignatureAlgorithmOID.DSA_WITH_SHA1
+OID_DSA_WITH_SHA224 = SignatureAlgorithmOID.DSA_WITH_SHA224
+OID_DSA_WITH_SHA256 = SignatureAlgorithmOID.DSA_WITH_SHA256
+OID_ECDSA_WITH_SHA1 = SignatureAlgorithmOID.ECDSA_WITH_SHA1
+OID_ECDSA_WITH_SHA224 = SignatureAlgorithmOID.ECDSA_WITH_SHA224
+OID_ECDSA_WITH_SHA256 = SignatureAlgorithmOID.ECDSA_WITH_SHA256
+OID_ECDSA_WITH_SHA384 = SignatureAlgorithmOID.ECDSA_WITH_SHA384
+OID_ECDSA_WITH_SHA512 = SignatureAlgorithmOID.ECDSA_WITH_SHA512
+OID_RSA_WITH_MD5 = SignatureAlgorithmOID.RSA_WITH_MD5
+OID_RSA_WITH_SHA1 = SignatureAlgorithmOID.RSA_WITH_SHA1
+OID_RSA_WITH_SHA224 = SignatureAlgorithmOID.RSA_WITH_SHA224
+OID_RSA_WITH_SHA256 = SignatureAlgorithmOID.RSA_WITH_SHA256
+OID_RSA_WITH_SHA384 = SignatureAlgorithmOID.RSA_WITH_SHA384
+OID_RSA_WITH_SHA512 = SignatureAlgorithmOID.RSA_WITH_SHA512
+
+OID_COMMON_NAME = NameOID.COMMON_NAME
+OID_COUNTRY_NAME = NameOID.COUNTRY_NAME
+OID_DOMAIN_COMPONENT = NameOID.DOMAIN_COMPONENT
+OID_DN_QUALIFIER = NameOID.DN_QUALIFIER
+OID_EMAIL_ADDRESS = NameOID.EMAIL_ADDRESS
+OID_GENERATION_QUALIFIER = NameOID.GENERATION_QUALIFIER
+OID_GIVEN_NAME = NameOID.GIVEN_NAME
+OID_LOCALITY_NAME = NameOID.LOCALITY_NAME
+OID_ORGANIZATIONAL_UNIT_NAME = NameOID.ORGANIZATIONAL_UNIT_NAME
+OID_ORGANIZATION_NAME = NameOID.ORGANIZATION_NAME
+OID_PSEUDONYM = NameOID.PSEUDONYM
+OID_SERIAL_NUMBER = NameOID.SERIAL_NUMBER
+OID_STATE_OR_PROVINCE_NAME = NameOID.STATE_OR_PROVINCE_NAME
+OID_SURNAME = NameOID.SURNAME
+OID_TITLE = NameOID.TITLE
+
+OID_CLIENT_AUTH = ExtendedKeyUsageOID.CLIENT_AUTH
+OID_CODE_SIGNING = ExtendedKeyUsageOID.CODE_SIGNING
+OID_EMAIL_PROTECTION = ExtendedKeyUsageOID.EMAIL_PROTECTION
+OID_OCSP_SIGNING = ExtendedKeyUsageOID.OCSP_SIGNING
+OID_SERVER_AUTH = ExtendedKeyUsageOID.SERVER_AUTH
+OID_TIME_STAMPING = ExtendedKeyUsageOID.TIME_STAMPING
+
+OID_ANY_POLICY = CertificatePoliciesOID.ANY_POLICY
+OID_CPS_QUALIFIER = CertificatePoliciesOID.CPS_QUALIFIER
+OID_CPS_USER_NOTICE = CertificatePoliciesOID.CPS_USER_NOTICE
+
+OID_CERTIFICATE_ISSUER = CRLExtensionOID.CERTIFICATE_ISSUER
+OID_CRL_REASON = CRLExtensionOID.CRL_REASON
+OID_INVALIDITY_DATE = CRLExtensionOID.INVALIDITY_DATE
+
+OID_CA_ISSUERS = AuthorityInformationAccessOID.CA_ISSUERS
+OID_OCSP = AuthorityInformationAccessOID.OCSP
+
+
+__all__ = [
+    "load_pem_x509_certificate",
+    "load_der_x509_certificate",
+    "load_pem_x509_csr",
+    "load_der_x509_csr",
+    "load_pem_x509_crl",
+    "load_der_x509_crl",
+    "InvalidVersion",
+    "DuplicateExtension",
+    "UnsupportedExtension",
+    "ExtensionNotFound",
+    "UnsupportedGeneralNameType",
+    "NameAttribute",
+    "Name",
+    "ObjectIdentifier",
+    "ExtensionType",
+    "Extensions",
+    "Extension",
+    "ExtendedKeyUsage",
+    "OCSPNoCheck",
+    "BasicConstraints",
+    "KeyUsage",
+    "AuthorityInformationAccess",
+    "AccessDescription",
+    "CertificatePolicies",
+    "PolicyInformation",
+    "UserNotice",
+    "NoticeReference",
+    "SubjectKeyIdentifier",
+    "NameConstraints",
+    "CRLDistributionPoints",
+    "DistributionPoint",
+    "ReasonFlags",
+    "InhibitAnyPolicy",
+    "SubjectAlternativeName",
+    "IssuerAlternativeName",
+    "AuthorityKeyIdentifier",
+    "GeneralNames",
+    "GeneralName",
+    "RFC822Name",
+    "DNSName",
+    "UniformResourceIdentifier",
+    "RegisteredID",
+    "DirectoryName",
+    "IPAddress",
+    "OtherName",
+    "Certificate",
+    "CertificateRevocationList",
+    "CertificateSigningRequest",
+    "RevokedCertificate",
+    "CertificateSigningRequestBuilder",
+    "CertificateBuilder",
+    "Version",
+    "_SIG_OIDS_TO_HASH",
+    "OID_CA_ISSUERS",
+    "OID_OCSP",
+    "_GENERAL_NAMES",
+]

lib/python3.5/site-packages/cryptography/x509/base.py

@@ -0,0 +1,467 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import abc
+import datetime
+from enum import Enum
+
+import six
+
+from cryptography import utils
+from cryptography.hazmat.primitives.asymmetric import dsa, ec, rsa
+from cryptography.x509.extensions import Extension, ExtensionType
+from cryptography.x509.name import Name
+
+
+_UNIX_EPOCH = datetime.datetime(1970, 1, 1)
+
+
+class Version(Enum):
+    v1 = 0
+    v3 = 2
+
+
+def load_pem_x509_certificate(data, backend):
+    return backend.load_pem_x509_certificate(data)
+
+
+def load_der_x509_certificate(data, backend):
+    return backend.load_der_x509_certificate(data)
+
+
+def load_pem_x509_csr(data, backend):
+    return backend.load_pem_x509_csr(data)
+
+
+def load_der_x509_csr(data, backend):
+    return backend.load_der_x509_csr(data)
+
+
+def load_pem_x509_crl(data, backend):
+    return backend.load_pem_x509_crl(data)
+
+
+def load_der_x509_crl(data, backend):
+    return backend.load_der_x509_crl(data)
+
+
+class InvalidVersion(Exception):
+    def __init__(self, msg, parsed_version):
+        super(InvalidVersion, self).__init__(msg)
+        self.parsed_version = parsed_version
+
+
+@six.add_metaclass(abc.ABCMeta)
+class Certificate(object):
+    @abc.abstractmethod
+    def fingerprint(self, algorithm):
+        """
+        Returns bytes using digest passed.
+        """
+
+    @abc.abstractproperty
+    def serial(self):
+        """
+        Returns certificate serial number
+        """
+
+    @abc.abstractproperty
+    def version(self):
+        """
+        Returns the certificate version
+        """
+
+    @abc.abstractmethod
+    def public_key(self):
+        """
+        Returns the public key
+        """
+
+    @abc.abstractproperty
+    def not_valid_before(self):
+        """
+        Not before time (represented as UTC datetime)
+        """
+
+    @abc.abstractproperty
+    def not_valid_after(self):
+        """
+        Not after time (represented as UTC datetime)
+        """
+
+    @abc.abstractproperty
+    def issuer(self):
+        """
+        Returns the issuer name object.
+        """
+
+    @abc.abstractproperty
+    def subject(self):
+        """
+        Returns the subject name object.
+        """
+
+    @abc.abstractproperty
+    def signature_hash_algorithm(self):
+        """
+        Returns a HashAlgorithm corresponding to the type of the digest signed
+        in the certificate.
+        """
+
+    @abc.abstractproperty
+    def extensions(self):
+        """
+        Returns an Extensions object.
+        """
+
+    @abc.abstractmethod
+    def __eq__(self, other):
+        """
+        Checks equality.
+        """
+
+    @abc.abstractmethod
+    def __ne__(self, other):
+        """
+        Checks not equal.
+        """
+
+    @abc.abstractmethod
+    def __hash__(self):
+        """
+        Computes a hash.
+        """
+
+    @abc.abstractmethod
+    def public_bytes(self, encoding):
+        """
+        Serializes the certificate to PEM or DER format.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class CertificateRevocationList(object):
+
+    @abc.abstractmethod
+    def fingerprint(self, algorithm):
+        """
+        Returns bytes using digest passed.
+        """
+
+    @abc.abstractproperty
+    def signature_hash_algorithm(self):
+        """
+        Returns a HashAlgorithm corresponding to the type of the digest signed
+        in the certificate.
+        """
+
+    @abc.abstractproperty
+    def issuer(self):
+        """
+        Returns the X509Name with the issuer of this CRL.
+        """
+
+    @abc.abstractproperty
+    def next_update(self):
+        """
+        Returns the date of next update for this CRL.
+        """
+
+    @abc.abstractproperty
+    def last_update(self):
+        """
+        Returns the date of last update for this CRL.
+        """
+
+    @abc.abstractproperty
+    def extensions(self):
+        """
+        Returns an Extensions object containing a list of CRL extensions.
+        """
+
+    @abc.abstractmethod
+    def __eq__(self, other):
+        """
+        Checks equality.
+        """
+
+    @abc.abstractmethod
+    def __ne__(self, other):
+        """
+        Checks not equal.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class CertificateSigningRequest(object):
+    @abc.abstractmethod
+    def __eq__(self, other):
+        """
+        Checks equality.
+        """
+
+    @abc.abstractmethod
+    def __ne__(self, other):
+        """
+        Checks not equal.
+        """
+
+    @abc.abstractmethod
+    def __hash__(self):
+        """
+        Computes a hash.
+        """
+
+    @abc.abstractmethod
+    def public_key(self):
+        """
+        Returns the public key
+        """
+
+    @abc.abstractproperty
+    def subject(self):
+        """
+        Returns the subject name object.
+        """
+
+    @abc.abstractproperty
+    def signature_hash_algorithm(self):
+        """
+        Returns a HashAlgorithm corresponding to the type of the digest signed
+        in the certificate.
+        """
+
+    @abc.abstractproperty
+    def extensions(self):
+        """
+        Returns the extensions in the signing request.
+        """
+
+    @abc.abstractmethod
+    def public_bytes(self, encoding):
+        """
+        Encodes the request to PEM or DER format.
+        """
+
+
+@six.add_metaclass(abc.ABCMeta)
+class RevokedCertificate(object):
+    @abc.abstractproperty
+    def serial_number(self):
+        """
+        Returns the serial number of the revoked certificate.
+        """
+
+    @abc.abstractproperty
+    def revocation_date(self):
+        """
+        Returns the date of when this certificate was revoked.
+        """
+
+    @abc.abstractproperty
+    def extensions(self):
+        """
+        Returns an Extensions object containing a list of Revoked extensions.
+        """
+
+
+class CertificateSigningRequestBuilder(object):
+    def __init__(self, subject_name=None, extensions=[]):
+        """
+        Creates an empty X.509 certificate request (v1).
+        """
+        self._subject_name = subject_name
+        self._extensions = extensions
+
+    def subject_name(self, name):
+        """
+        Sets the certificate requestor's distinguished name.
+        """
+        if not isinstance(name, Name):
+            raise TypeError('Expecting x509.Name object.')
+        if self._subject_name is not None:
+            raise ValueError('The subject name may only be set once.')
+        return CertificateSigningRequestBuilder(name, self._extensions)
+
+    def add_extension(self, extension, critical):
+        """
+        Adds an X.509 extension to the certificate request.
+        """
+        if not isinstance(extension, ExtensionType):
+            raise TypeError("extension must be an ExtensionType")
+
+        extension = Extension(extension.oid, critical, extension)
+
+        # TODO: This is quadratic in the number of extensions
+        for e in self._extensions:
+            if e.oid == extension.oid:
+                raise ValueError('This extension has already been set.')
+        return CertificateSigningRequestBuilder(
+            self._subject_name, self._extensions + [extension]
+        )
+
+    def sign(self, private_key, algorithm, backend):
+        """
+        Signs the request using the requestor's private key.
+        """
+        if self._subject_name is None:
+            raise ValueError("A CertificateSigningRequest must have a subject")
+        return backend.create_x509_csr(self, private_key, algorithm)
+
+
+class CertificateBuilder(object):
+    def __init__(self, issuer_name=None, subject_name=None,
+                 public_key=None, serial_number=None, not_valid_before=None,
+                 not_valid_after=None, extensions=[]):
+        self._version = Version.v3
+        self._issuer_name = issuer_name
+        self._subject_name = subject_name
+        self._public_key = public_key
+        self._serial_number = serial_number
+        self._not_valid_before = not_valid_before
+        self._not_valid_after = not_valid_after
+        self._extensions = extensions
+
+    def issuer_name(self, name):
+        """
+        Sets the CA's distinguished name.
+        """
+        if not isinstance(name, Name):
+            raise TypeError('Expecting x509.Name object.')
+        if self._issuer_name is not None:
+            raise ValueError('The issuer name may only be set once.')
+        return CertificateBuilder(
+            name, self._subject_name, self._public_key,
+            self._serial_number, self._not_valid_before,
+            self._not_valid_after, self._extensions
+        )
+
+    def subject_name(self, name):
+        """
+        Sets the requestor's distinguished name.
+        """
+        if not isinstance(name, Name):
+            raise TypeError('Expecting x509.Name object.')
+        if self._subject_name is not None:
+            raise ValueError('The subject name may only be set once.')
+        return CertificateBuilder(
+            self._issuer_name, name, self._public_key,
+            self._serial_number, self._not_valid_before,
+            self._not_valid_after, self._extensions
+        )
+
+    def public_key(self, key):
+        """
+        Sets the requestor's public key (as found in the signing request).
+        """
+        if not isinstance(key, (dsa.DSAPublicKey, rsa.RSAPublicKey,
+                                ec.EllipticCurvePublicKey)):
+            raise TypeError('Expecting one of DSAPublicKey, RSAPublicKey,'
+                            ' or EllipticCurvePublicKey.')
+        if self._public_key is not None:
+            raise ValueError('The public key may only be set once.')
+        return CertificateBuilder(
+            self._issuer_name, self._subject_name, key,
+            self._serial_number, self._not_valid_before,
+            self._not_valid_after, self._extensions
+        )
+
+    def serial_number(self, number):
+        """
+        Sets the certificate serial number.
+        """
+        if not isinstance(number, six.integer_types):
+            raise TypeError('Serial number must be of integral type.')
+        if self._serial_number is not None:
+            raise ValueError('The serial number may only be set once.')
+        if number < 0:
+            raise ValueError('The serial number should be non-negative.')
+        if utils.bit_length(number) > 160:  # As defined in RFC 5280
+            raise ValueError('The serial number should not be more than 160 '
+                             'bits.')
+        return CertificateBuilder(
+            self._issuer_name, self._subject_name,
+            self._public_key, number, self._not_valid_before,
+            self._not_valid_after, self._extensions
+        )
+
+    def not_valid_before(self, time):
+        """
+        Sets the certificate activation time.
+        """
+        if not isinstance(time, datetime.datetime):
+            raise TypeError('Expecting datetime object.')
+        if self._not_valid_before is not None:
+            raise ValueError('The not valid before may only be set once.')
+        if time <= _UNIX_EPOCH:
+            raise ValueError('The not valid before date must be after the unix'
+                             ' epoch (1970 January 1).')
+        return CertificateBuilder(
+            self._issuer_name, self._subject_name,
+            self._public_key, self._serial_number, time,
+            self._not_valid_after, self._extensions
+        )
+
+    def not_valid_after(self, time):
+        """
+        Sets the certificate expiration time.
+        """
+        if not isinstance(time, datetime.datetime):
+            raise TypeError('Expecting datetime object.')
+        if self._not_valid_after is not None:
+            raise ValueError('The not valid after may only be set once.')
+        if time <= _UNIX_EPOCH:
+            raise ValueError('The not valid after date must be after the unix'
+                             ' epoch (1970 January 1).')
+        return CertificateBuilder(
+            self._issuer_name, self._subject_name,
+            self._public_key, self._serial_number, self._not_valid_before,
+            time, self._extensions
+        )
+
+    def add_extension(self, extension, critical):
+        """
+        Adds an X.509 extension to the certificate.
+        """
+        if not isinstance(extension, ExtensionType):
+            raise TypeError("extension must be an ExtensionType")
+
+        extension = Extension(extension.oid, critical, extension)
+
+        # TODO: This is quadratic in the number of extensions
+        for e in self._extensions:
+            if e.oid == extension.oid:
+                raise ValueError('This extension has already been set.')
+
+        return CertificateBuilder(
+            self._issuer_name, self._subject_name,
+            self._public_key, self._serial_number, self._not_valid_before,
+            self._not_valid_after, self._extensions + [extension]
+        )
+
+    def sign(self, private_key, algorithm, backend):
+        """
+        Signs the certificate using the CA's private key.
+        """
+        if self._subject_name is None:
+            raise ValueError("A certificate must have a subject name")
+
+        if self._issuer_name is None:
+            raise ValueError("A certificate must have an issuer name")
+
+        if self._serial_number is None:
+            raise ValueError("A certificate must have a serial number")
+
+        if self._not_valid_before is None:
+            raise ValueError("A certificate must have a not valid before time")
+
+        if self._not_valid_after is None:
+            raise ValueError("A certificate must have a not valid after time")
+
+        if self._public_key is None:
+            raise ValueError("A certificate must have a public key")
+
+        return backend.create_x509_certificate(self, private_key, algorithm)

lib/python3.5/site-packages/cryptography/x509/extensions.py

@@ -0,0 +1,924 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import abc
+import hashlib
+import ipaddress
+from enum import Enum
+
+from pyasn1.codec.der import decoder
+from pyasn1.type import namedtype, univ
+
+import six
+
+from cryptography import utils
+from cryptography.hazmat.primitives import constant_time, serialization
+from cryptography.x509.general_name import GeneralName, IPAddress, OtherName
+from cryptography.x509.name import Name
+from cryptography.x509.oid import (
+    AuthorityInformationAccessOID, ExtensionOID, ObjectIdentifier
+)
+
+
+class _SubjectPublicKeyInfo(univ.Sequence):
+    componentType = namedtype.NamedTypes(
+        namedtype.NamedType('algorithm', univ.Sequence()),
+        namedtype.NamedType('subjectPublicKey', univ.BitString())
+    )
+
+
+def _key_identifier_from_public_key(public_key):
+    # This is a very slow way to do this.
+    serialized = public_key.public_bytes(
+        serialization.Encoding.DER,
+        serialization.PublicFormat.SubjectPublicKeyInfo
+    )
+    spki, remaining = decoder.decode(
+        serialized, asn1Spec=_SubjectPublicKeyInfo()
+    )
+    assert not remaining
+    # the univ.BitString object is a tuple of bits. We need bytes and
+    # pyasn1 really doesn't want to give them to us. To get it we'll
+    # build an integer and convert that to bytes.
+    bits = 0
+    for bit in spki.getComponentByName("subjectPublicKey"):
+        bits = bits << 1 | bit
+
+    data = utils.int_to_bytes(bits)
+    return hashlib.sha1(data).digest()
+
+
+class DuplicateExtension(Exception):
+    def __init__(self, msg, oid):
+        super(DuplicateExtension, self).__init__(msg)
+        self.oid = oid
+
+
+class UnsupportedExtension(Exception):
+    def __init__(self, msg, oid):
+        super(UnsupportedExtension, self).__init__(msg)
+        self.oid = oid
+
+
+class ExtensionNotFound(Exception):
+    def __init__(self, msg, oid):
+        super(ExtensionNotFound, self).__init__(msg)
+        self.oid = oid
+
+
+@six.add_metaclass(abc.ABCMeta)
+class ExtensionType(object):
+    @abc.abstractproperty
+    def oid(self):
+        """
+        Returns the oid associated with the given extension type.
+        """
+
+
+class Extensions(object):
+    def __init__(self, extensions):
+        self._extensions = extensions
+
+    def get_extension_for_oid(self, oid):
+        for ext in self:
+            if ext.oid == oid:
+                return ext
+
+        raise ExtensionNotFound("No {0} extension was found".format(oid), oid)
+
+    def get_extension_for_class(self, extclass):
+        for ext in self:
+            if isinstance(ext.value, extclass):
+                return ext
+
+        raise ExtensionNotFound(
+            "No {0} extension was found".format(extclass), extclass.oid
+        )
+
+    def __iter__(self):
+        return iter(self._extensions)
+
+    def __len__(self):
+        return len(self._extensions)
+
+    def __repr__(self):
+        return (
+            "<Extensions({0})>".format(self._extensions)
+        )
+
+
+@utils.register_interface(ExtensionType)
+class AuthorityKeyIdentifier(object):
+    oid = ExtensionOID.AUTHORITY_KEY_IDENTIFIER
+
+    def __init__(self, key_identifier, authority_cert_issuer,
+                 authority_cert_serial_number):
+        if authority_cert_issuer or authority_cert_serial_number:
+            if not authority_cert_issuer or not authority_cert_serial_number:
+                raise ValueError(
+                    "authority_cert_issuer and authority_cert_serial_number "
+                    "must both be present or both None"
+                )
+
+            if not all(
+                isinstance(x, GeneralName) for x in authority_cert_issuer
+            ):
+                raise TypeError(
+                    "authority_cert_issuer must be a list of GeneralName "
+                    "objects"
+                )
+
+            if not isinstance(authority_cert_serial_number, six.integer_types):
+                raise TypeError(
+                    "authority_cert_serial_number must be an integer"
+                )
+
+        self._key_identifier = key_identifier
+        self._authority_cert_issuer = authority_cert_issuer
+        self._authority_cert_serial_number = authority_cert_serial_number
+
+    @classmethod
+    def from_issuer_public_key(cls, public_key):
+        digest = _key_identifier_from_public_key(public_key)
+        return cls(
+            key_identifier=digest,
+            authority_cert_issuer=None,
+            authority_cert_serial_number=None
+        )
+
+    def __repr__(self):
+        return (
+            "<AuthorityKeyIdentifier(key_identifier={0.key_identifier!r}, "
+            "authority_cert_issuer={0.authority_cert_issuer}, "
+            "authority_cert_serial_number={0.authority_cert_serial_number}"
+            ")>".format(self)
+        )
+
+    def __eq__(self, other):
+        if not isinstance(other, AuthorityKeyIdentifier):
+            return NotImplemented
+
+        return (
+            self.key_identifier == other.key_identifier and
+            self.authority_cert_issuer == other.authority_cert_issuer and
+            self.authority_cert_serial_number ==
+            other.authority_cert_serial_number
+        )
+
+    def __ne__(self, other):
+        return not self == other
+
+    key_identifier = utils.read_only_property("_key_identifier")
+    authority_cert_issuer = utils.read_only_property("_authority_cert_issuer")
+    authority_cert_serial_number = utils.read_only_property(
+        "_authority_cert_serial_number"
+    )
+
+
+@utils.register_interface(ExtensionType)
+class SubjectKeyIdentifier(object):
+    oid = ExtensionOID.SUBJECT_KEY_IDENTIFIER
+
+    def __init__(self, digest):
+        self._digest = digest
+
+    @classmethod
+    def from_public_key(cls, public_key):
+        return cls(_key_identifier_from_public_key(public_key))
+
+    digest = utils.read_only_property("_digest")
+
+    def __repr__(self):
+        return "<SubjectKeyIdentifier(digest={0!r})>".format(self.digest)
+
+    def __eq__(self, other):
+        if not isinstance(other, SubjectKeyIdentifier):
+            return NotImplemented
+
+        return constant_time.bytes_eq(self.digest, other.digest)
+
+    def __ne__(self, other):
+        return not self == other
+
+
+@utils.register_interface(ExtensionType)
+class AuthorityInformationAccess(object):
+    oid = ExtensionOID.AUTHORITY_INFORMATION_ACCESS
+
+    def __init__(self, descriptions):
+        if not all(isinstance(x, AccessDescription) for x in descriptions):
+            raise TypeError(
+                "Every item in the descriptions list must be an "
+                "AccessDescription"
+            )
+
+        self._descriptions = descriptions
+
+    def __iter__(self):
+        return iter(self._descriptions)
+
+    def __len__(self):
+        return len(self._descriptions)
+
+    def __repr__(self):
+        return "<AuthorityInformationAccess({0})>".format(self._descriptions)
+
+    def __eq__(self, other):
+        if not isinstance(other, AuthorityInformationAccess):
+            return NotImplemented
+
+        return self._descriptions == other._descriptions
+
+    def __ne__(self, other):
+        return not self == other
+
+
+class AccessDescription(object):
+    def __init__(self, access_method, access_location):
+        if not (access_method == AuthorityInformationAccessOID.OCSP or
+                access_method == AuthorityInformationAccessOID.CA_ISSUERS):
+            raise ValueError(
+                "access_method must be OID_OCSP or OID_CA_ISSUERS"
+            )
+
+        if not isinstance(access_location, GeneralName):
+            raise TypeError("access_location must be a GeneralName")
+
+        self._access_method = access_method
+        self._access_location = access_location
+
+    def __repr__(self):
+        return (
+            "<AccessDescription(access_method={0.access_method}, access_locati"
+            "on={0.access_location})>".format(self)
+        )
+
+    def __eq__(self, other):
+        if not isinstance(other, AccessDescription):
+            return NotImplemented
+
+        return (
+            self.access_method == other.access_method and
+            self.access_location == other.access_location
+        )
+
+    def __ne__(self, other):
+        return not self == other
+
+    access_method = utils.read_only_property("_access_method")
+    access_location = utils.read_only_property("_access_location")
+
+
+@utils.register_interface(ExtensionType)
+class BasicConstraints(object):
+    oid = ExtensionOID.BASIC_CONSTRAINTS
+
+    def __init__(self, ca, path_length):
+        if not isinstance(ca, bool):
+            raise TypeError("ca must be a boolean value")
+
+        if path_length is not None and not ca:
+            raise ValueError("path_length must be None when ca is False")
+
+        if (
+            path_length is not None and
+            (not isinstance(path_length, six.integer_types) or path_length < 0)
+        ):
+            raise TypeError(
+                "path_length must be a non-negative integer or None"
+            )
+
+        self._ca = ca
+        self._path_length = path_length
+
+    ca = utils.read_only_property("_ca")
+    path_length = utils.read_only_property("_path_length")
+
+    def __repr__(self):
+        return ("<BasicConstraints(ca={0.ca}, "
+                "path_length={0.path_length})>").format(self)
+
+    def __eq__(self, other):
+        if not isinstance(other, BasicConstraints):
+            return NotImplemented
+
+        return self.ca == other.ca and self.path_length == other.path_length
+
+    def __ne__(self, other):
+        return not self == other
+
+
+@utils.register_interface(ExtensionType)
+class CRLDistributionPoints(object):
+    oid = ExtensionOID.CRL_DISTRIBUTION_POINTS
+
+    def __init__(self, distribution_points):
+        if not all(
+            isinstance(x, DistributionPoint) for x in distribution_points
+        ):
+            raise TypeError(
+                "distribution_points must be a list of DistributionPoint "
+                "objects"
+            )
+
+        self._distribution_points = distribution_points
+
+    def __iter__(self):
+        return iter(self._distribution_points)
+
+    def __len__(self):
+        return len(self._distribution_points)
+
+    def __repr__(self):
+        return "<CRLDistributionPoints({0})>".format(self._distribution_points)
+
+    def __eq__(self, other):
+        if not isinstance(other, CRLDistributionPoints):
+            return NotImplemented
+
+        return self._distribution_points == other._distribution_points
+
+    def __ne__(self, other):
+        return not self == other
+
+
+class DistributionPoint(object):
+    def __init__(self, full_name, relative_name, reasons, crl_issuer):
+        if full_name and relative_name:
+            raise ValueError(
+                "You cannot provide both full_name and relative_name, at "
+                "least one must be None."
+            )
+
+        if full_name and not all(
+            isinstance(x, GeneralName) for x in full_name
+        ):
+            raise TypeError(
+                "full_name must be a list of GeneralName objects"
+            )
+
+        if relative_name and not isinstance(relative_name, Name):
+            raise TypeError("relative_name must be a Name")
+
+        if crl_issuer and not all(
+            isinstance(x, GeneralName) for x in crl_issuer
+        ):
+            raise TypeError(
+                "crl_issuer must be None or a list of general names"
+            )
+
+        if reasons and (not isinstance(reasons, frozenset) or not all(
+            isinstance(x, ReasonFlags) for x in reasons
+        )):
+            raise TypeError("reasons must be None or frozenset of ReasonFlags")
+
+        if reasons and (
+            ReasonFlags.unspecified in reasons or
+            ReasonFlags.remove_from_crl in reasons
+        ):
+            raise ValueError(
+                "unspecified and remove_from_crl are not valid reasons in a "
+                "DistributionPoint"
+            )
+
+        if reasons and not crl_issuer and not (full_name or relative_name):
+            raise ValueError(
+                "You must supply crl_issuer, full_name, or relative_name when "
+                "reasons is not None"
+            )
+
+        self._full_name = full_name
+        self._relative_name = relative_name
+        self._reasons = reasons
+        self._crl_issuer = crl_issuer
+
+    def __repr__(self):
+        return (
+            "<DistributionPoint(full_name={0.full_name}, relative_name={0.rela"
+            "tive_name}, reasons={0.reasons}, crl_issuer={0.crl_is"
+            "suer})>".format(self)
+        )
+
+    def __eq__(self, other):
+        if not isinstance(other, DistributionPoint):
+            return NotImplemented
+
+        return (
+            self.full_name == other.full_name and
+            self.relative_name == other.relative_name and
+            self.reasons == other.reasons and
+            self.crl_issuer == other.crl_issuer
+        )
+
+    def __ne__(self, other):
+        return not self == other
+
+    full_name = utils.read_only_property("_full_name")
+    relative_name = utils.read_only_property("_relative_name")
+    reasons = utils.read_only_property("_reasons")
+    crl_issuer = utils.read_only_property("_crl_issuer")
+
+
+class ReasonFlags(Enum):
+    unspecified = "unspecified"
+    key_compromise = "keyCompromise"
+    ca_compromise = "cACompromise"
+    affiliation_changed = "affiliationChanged"
+    superseded = "superseded"
+    cessation_of_operation = "cessationOfOperation"
+    certificate_hold = "certificateHold"
+    privilege_withdrawn = "privilegeWithdrawn"
+    aa_compromise = "aACompromise"
+    remove_from_crl = "removeFromCRL"
+
+
+@utils.register_interface(ExtensionType)
+class CertificatePolicies(object):
+    oid = ExtensionOID.CERTIFICATE_POLICIES
+
+    def __init__(self, policies):
+        if not all(isinstance(x, PolicyInformation) for x in policies):
+            raise TypeError(
+                "Every item in the policies list must be a "
+                "PolicyInformation"
+            )
+
+        self._policies = policies
+
+    def __iter__(self):
+        return iter(self._policies)
+
+    def __len__(self):
+        return len(self._policies)
+
+    def __repr__(self):
+        return "<CertificatePolicies({0})>".format(self._policies)
+
+    def __eq__(self, other):
+        if not isinstance(other, CertificatePolicies):
+            return NotImplemented
+
+        return self._policies == other._policies
+
+    def __ne__(self, other):
+        return not self == other
+
+
+class PolicyInformation(object):
+    def __init__(self, policy_identifier, policy_qualifiers):
+        if not isinstance(policy_identifier, ObjectIdentifier):
+            raise TypeError("policy_identifier must be an ObjectIdentifier")
+
+        self._policy_identifier = policy_identifier
+        if policy_qualifiers and not all(
+            isinstance(
+                x, (six.text_type, UserNotice)
+            ) for x in policy_qualifiers
+        ):
+            raise TypeError(
+                "policy_qualifiers must be a list of strings and/or UserNotice"
+                " objects or None"
+            )
+
+        self._policy_qualifiers = policy_qualifiers
+
+    def __repr__(self):
+        return (
+            "<PolicyInformation(policy_identifier={0.policy_identifier}, polic"
+            "y_qualifiers={0.policy_qualifiers})>".format(self)
+        )
+
+    def __eq__(self, other):
+        if not isinstance(other, PolicyInformation):
+            return NotImplemented
+
+        return (
+            self.policy_identifier == other.policy_identifier and
+            self.policy_qualifiers == other.policy_qualifiers
+        )
+
+    def __ne__(self, other):
+        return not self == other
+
+    policy_identifier = utils.read_only_property("_policy_identifier")
+    policy_qualifiers = utils.read_only_property("_policy_qualifiers")
+
+
+class UserNotice(object):
+    def __init__(self, notice_reference, explicit_text):
+        if notice_reference and not isinstance(
+            notice_reference, NoticeReference
+        ):
+            raise TypeError(
+                "notice_reference must be None or a NoticeReference"
+            )
+
+        self._notice_reference = notice_reference
+        self._explicit_text = explicit_text
+
+    def __repr__(self):
+        return (
+            "<UserNotice(notice_reference={0.notice_reference}, explicit_text="
+            "{0.explicit_text!r})>".format(self)
+        )
+
+    def __eq__(self, other):
+        if not isinstance(other, UserNotice):
+            return NotImplemented
+
+        return (
+            self.notice_reference == other.notice_reference and
+            self.explicit_text == other.explicit_text
+        )
+
+    def __ne__(self, other):
+        return not self == other
+
+    notice_reference = utils.read_only_property("_notice_reference")
+    explicit_text = utils.read_only_property("_explicit_text")
+
+
+class NoticeReference(object):
+    def __init__(self, organization, notice_numbers):
+        self._organization = organization
+        if not isinstance(notice_numbers, list) or not all(
+            isinstance(x, int) for x in notice_numbers
+        ):
+            raise TypeError(
+                "notice_numbers must be a list of integers"
+            )
+
+        self._notice_numbers = notice_numbers
+
+    def __repr__(self):
+        return (
+            "<NoticeReference(organization={0.organization!r}, notice_numbers="
+            "{0.notice_numbers})>".format(self)
+        )
+
+    def __eq__(self, other):
+        if not isinstance(other, NoticeReference):
+            return NotImplemented
+
+        return (
+            self.organization == other.organization and
+            self.notice_numbers == other.notice_numbers
+        )
+
+    def __ne__(self, other):
+        return not self == other
+
+    organization = utils.read_only_property("_organization")
+    notice_numbers = utils.read_only_property("_notice_numbers")
+
+
+@utils.register_interface(ExtensionType)
+class ExtendedKeyUsage(object):
+    oid = ExtensionOID.EXTENDED_KEY_USAGE
+
+    def __init__(self, usages):
+        if not all(isinstance(x, ObjectIdentifier) for x in usages):
+            raise TypeError(
+                "Every item in the usages list must be an ObjectIdentifier"
+            )
+
+        self._usages = usages
+
+    def __iter__(self):
+        return iter(self._usages)
+
+    def __len__(self):
+        return len(self._usages)
+
+    def __repr__(self):
+        return "<ExtendedKeyUsage({0})>".format(self._usages)
+
+    def __eq__(self, other):
+        if not isinstance(other, ExtendedKeyUsage):
+            return NotImplemented
+
+        return self._usages == other._usages
+
+    def __ne__(self, other):
+        return not self == other
+
+
+@utils.register_interface(ExtensionType)
+class OCSPNoCheck(object):
+    oid = ExtensionOID.OCSP_NO_CHECK
+
+
+@utils.register_interface(ExtensionType)
+class InhibitAnyPolicy(object):
+    oid = ExtensionOID.INHIBIT_ANY_POLICY
+
+    def __init__(self, skip_certs):
+        if not isinstance(skip_certs, six.integer_types):
+            raise TypeError("skip_certs must be an integer")
+
+        if skip_certs < 0:
+            raise ValueError("skip_certs must be a non-negative integer")
+
+        self._skip_certs = skip_certs
+
+    def __repr__(self):
+        return "<InhibitAnyPolicy(skip_certs={0.skip_certs})>".format(self)
+
+    def __eq__(self, other):
+        if not isinstance(other, InhibitAnyPolicy):
+            return NotImplemented
+
+        return self.skip_certs == other.skip_certs
+
+    def __ne__(self, other):
+        return not self == other
+
+    skip_certs = utils.read_only_property("_skip_certs")
+
+
+@utils.register_interface(ExtensionType)
+class KeyUsage(object):
+    oid = ExtensionOID.KEY_USAGE
+
+    def __init__(self, digital_signature, content_commitment, key_encipherment,
+                 data_encipherment, key_agreement, key_cert_sign, crl_sign,
+                 encipher_only, decipher_only):
+        if not key_agreement and (encipher_only or decipher_only):
+            raise ValueError(
+                "encipher_only and decipher_only can only be true when "
+                "key_agreement is true"
+            )
+
+        self._digital_signature = digital_signature
+        self._content_commitment = content_commitment
+        self._key_encipherment = key_encipherment
+        self._data_encipherment = data_encipherment
+        self._key_agreement = key_agreement
+        self._key_cert_sign = key_cert_sign
+        self._crl_sign = crl_sign
+        self._encipher_only = encipher_only
+        self._decipher_only = decipher_only
+
+    digital_signature = utils.read_only_property("_digital_signature")
+    content_commitment = utils.read_only_property("_content_commitment")
+    key_encipherment = utils.read_only_property("_key_encipherment")
+    data_encipherment = utils.read_only_property("_data_encipherment")
+    key_agreement = utils.read_only_property("_key_agreement")
+    key_cert_sign = utils.read_only_property("_key_cert_sign")
+    crl_sign = utils.read_only_property("_crl_sign")
+
+    @property
+    def encipher_only(self):
+        if not self.key_agreement:
+            raise ValueError(
+                "encipher_only is undefined unless key_agreement is true"
+            )
+        else:
+            return self._encipher_only
+
+    @property
+    def decipher_only(self):
+        if not self.key_agreement:
+            raise ValueError(
+                "decipher_only is undefined unless key_agreement is true"
+            )
+        else:
+            return self._decipher_only
+
+    def __repr__(self):
+        try:
+            encipher_only = self.encipher_only
+            decipher_only = self.decipher_only
+        except ValueError:
+            encipher_only = None
+            decipher_only = None
+
+        return ("<KeyUsage(digital_signature={0.digital_signature}, "
+                "content_commitment={0.content_commitment}, "
+                "key_encipherment={0.key_encipherment}, "
+                "data_encipherment={0.data_encipherment}, "
+                "key_agreement={0.key_agreement}, "
+                "key_cert_sign={0.key_cert_sign}, crl_sign={0.crl_sign}, "
+                "encipher_only={1}, decipher_only={2})>").format(
+                    self, encipher_only, decipher_only)
+
+    def __eq__(self, other):
+        if not isinstance(other, KeyUsage):
+            return NotImplemented
+
+        return (
+            self.digital_signature == other.digital_signature and
+            self.content_commitment == other.content_commitment and
+            self.key_encipherment == other.key_encipherment and
+            self.data_encipherment == other.data_encipherment and
+            self.key_agreement == other.key_agreement and
+            self.key_cert_sign == other.key_cert_sign and
+            self.crl_sign == other.crl_sign and
+            self._encipher_only == other._encipher_only and
+            self._decipher_only == other._decipher_only
+        )
+
+    def __ne__(self, other):
+        return not self == other
+
+
+@utils.register_interface(ExtensionType)
+class NameConstraints(object):
+    oid = ExtensionOID.NAME_CONSTRAINTS
+
+    def __init__(self, permitted_subtrees, excluded_subtrees):
+        if permitted_subtrees is not None:
+            if not all(
+                isinstance(x, GeneralName) for x in permitted_subtrees
+            ):
+                raise TypeError(
+                    "permitted_subtrees must be a list of GeneralName objects "
+                    "or None"
+                )
+
+            self._validate_ip_name(permitted_subtrees)
+
+        if excluded_subtrees is not None:
+            if not all(
+                isinstance(x, GeneralName) for x in excluded_subtrees
+            ):
+                raise TypeError(
+                    "excluded_subtrees must be a list of GeneralName objects "
+                    "or None"
+                )
+
+            self._validate_ip_name(excluded_subtrees)
+
+        if permitted_subtrees is None and excluded_subtrees is None:
+            raise ValueError(
+                "At least one of permitted_subtrees and excluded_subtrees "
+                "must not be None"
+            )
+
+        self._permitted_subtrees = permitted_subtrees
+        self._excluded_subtrees = excluded_subtrees
+
+    def __eq__(self, other):
+        if not isinstance(other, NameConstraints):
+            return NotImplemented
+
+        return (
+            self.excluded_subtrees == other.excluded_subtrees and
+            self.permitted_subtrees == other.permitted_subtrees
+        )
+
+    def __ne__(self, other):
+        return not self == other
+
+    def _validate_ip_name(self, tree):
+        if any(isinstance(name, IPAddress) and not isinstance(
+            name.value, (ipaddress.IPv4Network, ipaddress.IPv6Network)
+        ) for name in tree):
+            raise TypeError(
+                "IPAddress name constraints must be an IPv4Network or"
+                " IPv6Network object"
+            )
+
+    def __repr__(self):
+        return (
+            u"<NameConstraints(permitted_subtrees={0.permitted_subtrees}, "
+            u"excluded_subtrees={0.excluded_subtrees})>".format(self)
+        )
+
+    permitted_subtrees = utils.read_only_property("_permitted_subtrees")
+    excluded_subtrees = utils.read_only_property("_excluded_subtrees")
+
+
+class Extension(object):
+    def __init__(self, oid, critical, value):
+        if not isinstance(oid, ObjectIdentifier):
+            raise TypeError(
+                "oid argument must be an ObjectIdentifier instance."
+            )
+
+        if not isinstance(critical, bool):
+            raise TypeError("critical must be a boolean value")
+
+        self._oid = oid
+        self._critical = critical
+        self._value = value
+
+    oid = utils.read_only_property("_oid")
+    critical = utils.read_only_property("_critical")
+    value = utils.read_only_property("_value")
+
+    def __repr__(self):
+        return ("<Extension(oid={0.oid}, critical={0.critical}, "
+                "value={0.value})>").format(self)
+
+    def __eq__(self, other):
+        if not isinstance(other, Extension):
+            return NotImplemented
+
+        return (
+            self.oid == other.oid and
+            self.critical == other.critical and
+            self.value == other.value
+        )
+
+    def __ne__(self, other):
+        return not self == other
+
+
+class GeneralNames(object):
+    def __init__(self, general_names):
+        if not all(isinstance(x, GeneralName) for x in general_names):
+            raise TypeError(
+                "Every item in the general_names list must be an "
+                "object conforming to the GeneralName interface"
+            )
+
+        self._general_names = general_names
+
+    def __iter__(self):
+        return iter(self._general_names)
+
+    def __len__(self):
+        return len(self._general_names)
+
+    def get_values_for_type(self, type):
+        # Return the value of each GeneralName, except for OtherName instances
+        # which we return directly because it has two important properties not
+        # just one value.
+        objs = (i for i in self if isinstance(i, type))
+        if type != OtherName:
+            objs = (i.value for i in objs)
+        return list(objs)
+
+    def __repr__(self):
+        return "<GeneralNames({0})>".format(self._general_names)
+
+    def __eq__(self, other):
+        if not isinstance(other, GeneralNames):
+            return NotImplemented
+
+        return self._general_names == other._general_names
+
+    def __ne__(self, other):
+        return not self == other
+
+
+@utils.register_interface(ExtensionType)
+class SubjectAlternativeName(object):
+    oid = ExtensionOID.SUBJECT_ALTERNATIVE_NAME
+
+    def __init__(self, general_names):
+        self._general_names = GeneralNames(general_names)
+
+    def __iter__(self):
+        return iter(self._general_names)
+
+    def __len__(self):
+        return len(self._general_names)
+
+    def get_values_for_type(self, type):
+        return self._general_names.get_values_for_type(type)
+
+    def __repr__(self):
+        return "<SubjectAlternativeName({0})>".format(self._general_names)
+
+    def __eq__(self, other):
+        if not isinstance(other, SubjectAlternativeName):
+            return NotImplemented
+
+        return self._general_names == other._general_names
+
+    def __ne__(self, other):
+        return not self == other
+
+
+@utils.register_interface(ExtensionType)
+class IssuerAlternativeName(object):
+    oid = ExtensionOID.ISSUER_ALTERNATIVE_NAME
+
+    def __init__(self, general_names):
+        self._general_names = GeneralNames(general_names)
+
+    def __iter__(self):
+        return iter(self._general_names)
+
+    def __len__(self):
+        return len(self._general_names)
+
+    def get_values_for_type(self, type):
+        return self._general_names.get_values_for_type(type)
+
+    def __repr__(self):
+        return "<IssuerAlternativeName({0})>".format(self._general_names)
+
+    def __eq__(self, other):
+        if not isinstance(other, IssuerAlternativeName):
+            return NotImplemented
+
+        return self._general_names == other._general_names
+
+    def __ne__(self, other):
+        return not self == other

lib/python3.5/site-packages/cryptography/x509/general_name.py

@@ -0,0 +1,265 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import abc
+import ipaddress
+from email.utils import parseaddr
+
+import idna
+
+import six
+
+from six.moves import urllib_parse
+
+from cryptography import utils
+from cryptography.x509.name import Name
+from cryptography.x509.oid import ObjectIdentifier
+
+
+_GENERAL_NAMES = {
+    0: "otherName",
+    1: "rfc822Name",
+    2: "dNSName",
+    3: "x400Address",
+    4: "directoryName",
+    5: "ediPartyName",
+    6: "uniformResourceIdentifier",
+    7: "iPAddress",
+    8: "registeredID",
+}
+
+
+class UnsupportedGeneralNameType(Exception):
+    def __init__(self, msg, type):
+        super(UnsupportedGeneralNameType, self).__init__(msg)
+        self.type = type
+
+
+@six.add_metaclass(abc.ABCMeta)
+class GeneralName(object):
+    @abc.abstractproperty
+    def value(self):
+        """
+        Return the value of the object
+        """
+
+
+@utils.register_interface(GeneralName)
+class RFC822Name(object):
+    def __init__(self, value):
+        if not isinstance(value, six.text_type):
+            raise TypeError("value must be a unicode string")
+
+        name, address = parseaddr(value)
+        parts = address.split(u"@")
+        if name or not address:
+            # parseaddr has found a name (e.g. Name <email>) or the entire
+            # value is an empty string.
+            raise ValueError("Invalid rfc822name value")
+        elif len(parts) == 1:
+            # Single label email name. This is valid for local delivery.
+            # No IDNA encoding needed since there is no domain component.
+            encoded = address.encode("ascii")
+        else:
+            # A normal email of the form user@domain.com. Let's attempt to
+            # encode the domain component and reconstruct the address.
+            encoded = parts[0].encode("ascii") + b"@" + idna.encode(parts[1])
+
+        self._value = value
+        self._encoded = encoded
+
+    value = utils.read_only_property("_value")
+
+    def __repr__(self):
+        return "<RFC822Name(value={0})>".format(self.value)
+
+    def __eq__(self, other):
+        if not isinstance(other, RFC822Name):
+            return NotImplemented
+
+        return self.value == other.value
+
+    def __ne__(self, other):
+        return not self == other
+
+
+@utils.register_interface(GeneralName)
+class DNSName(object):
+    def __init__(self, value):
+        if not isinstance(value, six.text_type):
+            raise TypeError("value must be a unicode string")
+
+        self._value = value
+
+    value = utils.read_only_property("_value")
+
+    def __repr__(self):
+        return "<DNSName(value={0})>".format(self.value)
+
+    def __eq__(self, other):
+        if not isinstance(other, DNSName):
+            return NotImplemented
+
+        return self.value == other.value
+
+    def __ne__(self, other):
+        return not self == other
+
+
+@utils.register_interface(GeneralName)
+class UniformResourceIdentifier(object):
+    def __init__(self, value):
+        if not isinstance(value, six.text_type):
+            raise TypeError("value must be a unicode string")
+
+        parsed = urllib_parse.urlparse(value)
+        if not parsed.hostname:
+            netloc = ""
+        elif parsed.port:
+            netloc = (
+                idna.encode(parsed.hostname) +
+                ":{0}".format(parsed.port).encode("ascii")
+            ).decode("ascii")
+        else:
+            netloc = idna.encode(parsed.hostname).decode("ascii")
+
+        # Note that building a URL in this fashion means it should be
+        # semantically indistinguishable from the original but is not
+        # guaranteed to be exactly the same.
+        uri = urllib_parse.urlunparse((
+            parsed.scheme,
+            netloc,
+            parsed.path,
+            parsed.params,
+            parsed.query,
+            parsed.fragment
+        )).encode("ascii")
+
+        self._value = value
+        self._encoded = uri
+
+    value = utils.read_only_property("_value")
+
+    def __repr__(self):
+        return "<UniformResourceIdentifier(value={0})>".format(self.value)
+
+    def __eq__(self, other):
+        if not isinstance(other, UniformResourceIdentifier):
+            return NotImplemented
+
+        return self.value == other.value
+
+    def __ne__(self, other):
+        return not self == other
+
+
+@utils.register_interface(GeneralName)
+class DirectoryName(object):
+    def __init__(self, value):
+        if not isinstance(value, Name):
+            raise TypeError("value must be a Name")
+
+        self._value = value
+
+    value = utils.read_only_property("_value")
+
+    def __repr__(self):
+        return "<DirectoryName(value={0})>".format(self.value)
+
+    def __eq__(self, other):
+        if not isinstance(other, DirectoryName):
+            return NotImplemented
+
+        return self.value == other.value
+
+    def __ne__(self, other):
+        return not self == other
+
+
+@utils.register_interface(GeneralName)
+class RegisteredID(object):
+    def __init__(self, value):
+        if not isinstance(value, ObjectIdentifier):
+            raise TypeError("value must be an ObjectIdentifier")
+
+        self._value = value
+
+    value = utils.read_only_property("_value")
+
+    def __repr__(self):
+        return "<RegisteredID(value={0})>".format(self.value)
+
+    def __eq__(self, other):
+        if not isinstance(other, RegisteredID):
+            return NotImplemented
+
+        return self.value == other.value
+
+    def __ne__(self, other):
+        return not self == other
+
+
+@utils.register_interface(GeneralName)
+class IPAddress(object):
+    def __init__(self, value):
+        if not isinstance(
+            value,
+            (
+                ipaddress.IPv4Address,
+                ipaddress.IPv6Address,
+                ipaddress.IPv4Network,
+                ipaddress.IPv6Network
+            )
+        ):
+            raise TypeError(
+                "value must be an instance of ipaddress.IPv4Address, "
+                "ipaddress.IPv6Address, ipaddress.IPv4Network, or "
+                "ipaddress.IPv6Network"
+            )
+
+        self._value = value
+
+    value = utils.read_only_property("_value")
+
+    def __repr__(self):
+        return "<IPAddress(value={0})>".format(self.value)
+
+    def __eq__(self, other):
+        if not isinstance(other, IPAddress):
+            return NotImplemented
+
+        return self.value == other.value
+
+    def __ne__(self, other):
+        return not self == other
+
+
+@utils.register_interface(GeneralName)
+class OtherName(object):
+    def __init__(self, type_id, value):
+        if not isinstance(type_id, ObjectIdentifier):
+            raise TypeError("type_id must be an ObjectIdentifier")
+        if not isinstance(value, bytes):
+            raise TypeError("value must be a binary string")
+
+        self._type_id = type_id
+        self._value = value
+
+    type_id = utils.read_only_property("_type_id")
+    value = utils.read_only_property("_value")
+
+    def __repr__(self):
+        return "<OtherName(type_id={0}, value={1!r})>".format(
+            self.type_id, self.value)
+
+    def __eq__(self, other):
+        if not isinstance(other, OtherName):
+            return NotImplemented
+
+        return self.type_id == other.type_id and self.value == other.value
+
+    def __ne__(self, other):
+        return not self == other

lib/python3.5/site-packages/cryptography/x509/name.py

@@ -0,0 +1,78 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+import six
+
+from cryptography import utils
+from cryptography.x509.oid import ObjectIdentifier
+
+
+class NameAttribute(object):
+    def __init__(self, oid, value):
+        if not isinstance(oid, ObjectIdentifier):
+            raise TypeError(
+                "oid argument must be an ObjectIdentifier instance."
+            )
+
+        if not isinstance(value, six.text_type):
+            raise TypeError(
+                "value argument must be a text type."
+            )
+
+        self._oid = oid
+        self._value = value
+
+    oid = utils.read_only_property("_oid")
+    value = utils.read_only_property("_value")
+
+    def __eq__(self, other):
+        if not isinstance(other, NameAttribute):
+            return NotImplemented
+
+        return (
+            self.oid == other.oid and
+            self.value == other.value
+        )
+
+    def __ne__(self, other):
+        return not self == other
+
+    def __hash__(self):
+        return hash((self.oid, self.value))
+
+    def __repr__(self):
+        return "<NameAttribute(oid={0.oid}, value={0.value!r})>".format(self)
+
+
+class Name(object):
+    def __init__(self, attributes):
+        self._attributes = attributes
+
+    def get_attributes_for_oid(self, oid):
+        return [i for i in self if i.oid == oid]
+
+    def __eq__(self, other):
+        if not isinstance(other, Name):
+            return NotImplemented
+
+        return self._attributes == other._attributes
+
+    def __ne__(self, other):
+        return not self == other
+
+    def __hash__(self):
+        # TODO: this is relatively expensive, if this looks like a bottleneck
+        # for you, consider optimizing!
+        return hash(tuple(self._attributes))
+
+    def __iter__(self):
+        return iter(self._attributes)
+
+    def __len__(self):
+        return len(self._attributes)
+
+    def __repr__(self):
+        return "<Name({0!r})>".format(self._attributes)

lib/python3.5/site-packages/cryptography/x509/oid.py

@@ -0,0 +1,199 @@
+# This file is dual licensed under the terms of the Apache License, Version
+# 2.0, and the BSD License. See the LICENSE file in the root of this repository
+# for complete details.
+
+from __future__ import absolute_import, division, print_function
+
+from cryptography import utils
+from cryptography.hazmat.primitives import hashes
+
+
+class ObjectIdentifier(object):
+    def __init__(self, dotted_string):
+        self._dotted_string = dotted_string
+
+    def __eq__(self, other):
+        if not isinstance(other, ObjectIdentifier):
+            return NotImplemented
+
+        return self.dotted_string == other.dotted_string
+
+    def __ne__(self, other):
+        return not self == other
+
+    def __repr__(self):
+        return "<ObjectIdentifier(oid={0}, name={1})>".format(
+            self.dotted_string,
+            self._name
+        )
+
+    def __hash__(self):
+        return hash(self.dotted_string)
+
+    @property
+    def _name(self):
+        return _OID_NAMES.get(self, "Unknown OID")
+
+    dotted_string = utils.read_only_property("_dotted_string")
+
+
+class ExtensionOID(object):
+    SUBJECT_DIRECTORY_ATTRIBUTES = ObjectIdentifier("2.5.29.9")
+    SUBJECT_KEY_IDENTIFIER = ObjectIdentifier("2.5.29.14")
+    KEY_USAGE = ObjectIdentifier("2.5.29.15")
+    SUBJECT_ALTERNATIVE_NAME = ObjectIdentifier("2.5.29.17")
+    ISSUER_ALTERNATIVE_NAME = ObjectIdentifier("2.5.29.18")
+    BASIC_CONSTRAINTS = ObjectIdentifier("2.5.29.19")
+    NAME_CONSTRAINTS = ObjectIdentifier("2.5.29.30")
+    CRL_DISTRIBUTION_POINTS = ObjectIdentifier("2.5.29.31")
+    CERTIFICATE_POLICIES = ObjectIdentifier("2.5.29.32")
+    POLICY_MAPPINGS = ObjectIdentifier("2.5.29.33")
+    AUTHORITY_KEY_IDENTIFIER = ObjectIdentifier("2.5.29.35")
+    POLICY_CONSTRAINTS = ObjectIdentifier("2.5.29.36")
+    EXTENDED_KEY_USAGE = ObjectIdentifier("2.5.29.37")
+    FRESHEST_CRL = ObjectIdentifier("2.5.29.46")
+    INHIBIT_ANY_POLICY = ObjectIdentifier("2.5.29.54")
+    AUTHORITY_INFORMATION_ACCESS = ObjectIdentifier("1.3.6.1.5.5.7.1.1")
+    SUBJECT_INFORMATION_ACCESS = ObjectIdentifier("1.3.6.1.5.5.7.1.11")
+    OCSP_NO_CHECK = ObjectIdentifier("1.3.6.1.5.5.7.48.1.5")
+
+
+class CRLExtensionOID(object):
+    CERTIFICATE_ISSUER = ObjectIdentifier("2.5.29.29")
+    CRL_REASON = ObjectIdentifier("2.5.29.21")
+    INVALIDITY_DATE = ObjectIdentifier("2.5.29.24")
+
+
+class NameOID(object):
+    COMMON_NAME = ObjectIdentifier("2.5.4.3")
+    COUNTRY_NAME = ObjectIdentifier("2.5.4.6")
+    LOCALITY_NAME = ObjectIdentifier("2.5.4.7")
+    STATE_OR_PROVINCE_NAME = ObjectIdentifier("2.5.4.8")
+    ORGANIZATION_NAME = ObjectIdentifier("2.5.4.10")
+    ORGANIZATIONAL_UNIT_NAME = ObjectIdentifier("2.5.4.11")
+    SERIAL_NUMBER = ObjectIdentifier("2.5.4.5")
+    SURNAME = ObjectIdentifier("2.5.4.4")
+    GIVEN_NAME = ObjectIdentifier("2.5.4.42")
+    TITLE = ObjectIdentifier("2.5.4.12")
+    GENERATION_QUALIFIER = ObjectIdentifier("2.5.4.44")
+    DN_QUALIFIER = ObjectIdentifier("2.5.4.46")
+    PSEUDONYM = ObjectIdentifier("2.5.4.65")
+    DOMAIN_COMPONENT = ObjectIdentifier("0.9.2342.19200300.100.1.25")
+    EMAIL_ADDRESS = ObjectIdentifier("1.2.840.113549.1.9.1")
+
+
+class SignatureAlgorithmOID(object):
+    RSA_WITH_MD5 = ObjectIdentifier("1.2.840.113549.1.1.4")
+    RSA_WITH_SHA1 = ObjectIdentifier("1.2.840.113549.1.1.5")
+    RSA_WITH_SHA224 = ObjectIdentifier("1.2.840.113549.1.1.14")
+    RSA_WITH_SHA256 = ObjectIdentifier("1.2.840.113549.1.1.11")
+    RSA_WITH_SHA384 = ObjectIdentifier("1.2.840.113549.1.1.12")
+    RSA_WITH_SHA512 = ObjectIdentifier("1.2.840.113549.1.1.13")
+    ECDSA_WITH_SHA1 = ObjectIdentifier("1.2.840.10045.4.1")
+    ECDSA_WITH_SHA224 = ObjectIdentifier("1.2.840.10045.4.3.1")
+    ECDSA_WITH_SHA256 = ObjectIdentifier("1.2.840.10045.4.3.2")
+    ECDSA_WITH_SHA384 = ObjectIdentifier("1.2.840.10045.4.3.3")
+    ECDSA_WITH_SHA512 = ObjectIdentifier("1.2.840.10045.4.3.4")
+    DSA_WITH_SHA1 = ObjectIdentifier("1.2.840.10040.4.3")
+    DSA_WITH_SHA224 = ObjectIdentifier("2.16.840.1.101.3.4.3.1")
+    DSA_WITH_SHA256 = ObjectIdentifier("2.16.840.1.101.3.4.3.2")
+
+_SIG_OIDS_TO_HASH = {
+    SignatureAlgorithmOID.RSA_WITH_MD5.dotted_string: hashes.MD5(),
+    SignatureAlgorithmOID.RSA_WITH_SHA1.dotted_string: hashes.SHA1(),
+    SignatureAlgorithmOID.RSA_WITH_SHA224.dotted_string: hashes.SHA224(),
+    SignatureAlgorithmOID.RSA_WITH_SHA256.dotted_string: hashes.SHA256(),
+    SignatureAlgorithmOID.RSA_WITH_SHA384.dotted_string: hashes.SHA384(),
+    SignatureAlgorithmOID.RSA_WITH_SHA512.dotted_string: hashes.SHA512(),
+    SignatureAlgorithmOID.ECDSA_WITH_SHA1.dotted_string: hashes.SHA1(),
+    SignatureAlgorithmOID.ECDSA_WITH_SHA224.dotted_string: hashes.SHA224(),
+    SignatureAlgorithmOID.ECDSA_WITH_SHA256.dotted_string: hashes.SHA256(),
+    SignatureAlgorithmOID.ECDSA_WITH_SHA384.dotted_string: hashes.SHA384(),
+    SignatureAlgorithmOID.ECDSA_WITH_SHA512.dotted_string: hashes.SHA512(),
+    SignatureAlgorithmOID.DSA_WITH_SHA1.dotted_string: hashes.SHA1(),
+    SignatureAlgorithmOID.DSA_WITH_SHA224.dotted_string: hashes.SHA224(),
+    SignatureAlgorithmOID.DSA_WITH_SHA256.dotted_string: hashes.SHA256()
+}
+
+
+class ExtendedKeyUsageOID(object):
+    SERVER_AUTH = ObjectIdentifier("1.3.6.1.5.5.7.3.1")
+    CLIENT_AUTH = ObjectIdentifier("1.3.6.1.5.5.7.3.2")
+    CODE_SIGNING = ObjectIdentifier("1.3.6.1.5.5.7.3.3")
+    EMAIL_PROTECTION = ObjectIdentifier("1.3.6.1.5.5.7.3.4")
+    TIME_STAMPING = ObjectIdentifier("1.3.6.1.5.5.7.3.8")
+    OCSP_SIGNING = ObjectIdentifier("1.3.6.1.5.5.7.3.9")
+
+
+class AuthorityInformationAccessOID(object):
+    CA_ISSUERS = ObjectIdentifier("1.3.6.1.5.5.7.48.2")
+    OCSP = ObjectIdentifier("1.3.6.1.5.5.7.48.1")
+
+
+class CertificatePoliciesOID(object):
+    CPS_QUALIFIER = ObjectIdentifier("1.3.6.1.5.5.7.2.1")
+    CPS_USER_NOTICE = ObjectIdentifier("1.3.6.1.5.5.7.2.2")
+    ANY_POLICY = ObjectIdentifier("2.5.29.32.0")
+
+_OID_NAMES = {
+    NameOID.COMMON_NAME: "commonName",
+    NameOID.COUNTRY_NAME: "countryName",
+    NameOID.LOCALITY_NAME: "localityName",
+    NameOID.STATE_OR_PROVINCE_NAME: "stateOrProvinceName",
+    NameOID.ORGANIZATION_NAME: "organizationName",
+    NameOID.ORGANIZATIONAL_UNIT_NAME: "organizationalUnitName",
+    NameOID.SERIAL_NUMBER: "serialNumber",
+    NameOID.SURNAME: "surname",
+    NameOID.GIVEN_NAME: "givenName",
+    NameOID.TITLE: "title",
+    NameOID.GENERATION_QUALIFIER: "generationQualifier",
+    NameOID.DN_QUALIFIER: "dnQualifier",
+    NameOID.PSEUDONYM: "pseudonym",
+    NameOID.DOMAIN_COMPONENT: "domainComponent",
+    NameOID.EMAIL_ADDRESS: "emailAddress",
+    SignatureAlgorithmOID.RSA_WITH_MD5: "md5WithRSAEncryption",
+    SignatureAlgorithmOID.RSA_WITH_SHA1: "sha1WithRSAEncryption",
+    SignatureAlgorithmOID.RSA_WITH_SHA224: "sha224WithRSAEncryption",
+    SignatureAlgorithmOID.RSA_WITH_SHA256: "sha256WithRSAEncryption",
+    SignatureAlgorithmOID.RSA_WITH_SHA384: "sha384WithRSAEncryption",
+    SignatureAlgorithmOID.RSA_WITH_SHA512: "sha512WithRSAEncryption",
+    SignatureAlgorithmOID.ECDSA_WITH_SHA1: "ecdsa-with-SHA1",
+    SignatureAlgorithmOID.ECDSA_WITH_SHA224: "ecdsa-with-SHA224",
+    SignatureAlgorithmOID.ECDSA_WITH_SHA256: "ecdsa-with-SHA256",
+    SignatureAlgorithmOID.ECDSA_WITH_SHA384: "ecdsa-with-SHA384",
+    SignatureAlgorithmOID.ECDSA_WITH_SHA512: "ecdsa-with-SHA512",
+    SignatureAlgorithmOID.DSA_WITH_SHA1: "dsa-with-sha1",
+    SignatureAlgorithmOID.DSA_WITH_SHA224: "dsa-with-sha224",
+    SignatureAlgorithmOID.DSA_WITH_SHA256: "dsa-with-sha256",
+    ExtendedKeyUsageOID.SERVER_AUTH: "serverAuth",
+    ExtendedKeyUsageOID.CLIENT_AUTH: "clientAuth",
+    ExtendedKeyUsageOID.CODE_SIGNING: "codeSigning",
+    ExtendedKeyUsageOID.EMAIL_PROTECTION: "emailProtection",
+    ExtendedKeyUsageOID.TIME_STAMPING: "timeStamping",
+    ExtendedKeyUsageOID.OCSP_SIGNING: "OCSPSigning",
+    ExtensionOID.SUBJECT_DIRECTORY_ATTRIBUTES: "subjectDirectoryAttributes",
+    ExtensionOID.SUBJECT_KEY_IDENTIFIER: "subjectKeyIdentifier",
+    ExtensionOID.KEY_USAGE: "keyUsage",
+    ExtensionOID.SUBJECT_ALTERNATIVE_NAME: "subjectAltName",
+    ExtensionOID.ISSUER_ALTERNATIVE_NAME: "issuerAltName",
+    ExtensionOID.BASIC_CONSTRAINTS: "basicConstraints",
+    CRLExtensionOID.CRL_REASON: "cRLReason",
+    CRLExtensionOID.INVALIDITY_DATE: "invalidityDate",
+    CRLExtensionOID.CERTIFICATE_ISSUER: "certificateIssuer",
+    ExtensionOID.NAME_CONSTRAINTS: "nameConstraints",
+    ExtensionOID.CRL_DISTRIBUTION_POINTS: "cRLDistributionPoints",
+    ExtensionOID.CERTIFICATE_POLICIES: "certificatePolicies",
+    ExtensionOID.POLICY_MAPPINGS: "policyMappings",
+    ExtensionOID.AUTHORITY_KEY_IDENTIFIER: "authorityKeyIdentifier",
+    ExtensionOID.POLICY_CONSTRAINTS: "policyConstraints",
+    ExtensionOID.EXTENDED_KEY_USAGE: "extendedKeyUsage",
+    ExtensionOID.FRESHEST_CRL: "freshestCRL",
+    ExtensionOID.INHIBIT_ANY_POLICY: "inhibitAnyPolicy",
+    ExtensionOID.AUTHORITY_INFORMATION_ACCESS: "authorityInfoAccess",
+    ExtensionOID.SUBJECT_INFORMATION_ACCESS: "subjectInfoAccess",
+    ExtensionOID.OCSP_NO_CHECK: "OCSPNoCheck",
+    AuthorityInformationAccessOID.OCSP: "OCSP",
+    AuthorityInformationAccessOID.CA_ISSUERS: "caIssuers",
+    CertificatePoliciesOID.CPS_QUALIFIER: "id-qt-cps",
+    CertificatePoliciesOID.CPS_USER_NOTICE: "id-qt-unotice",
+}