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# 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
)
from cryptography.hazmat.backends.multibackend import MultiBackend
from cryptography.hazmat.primitives import cmac, hashes, hmac
from cryptography.hazmat.primitives.asymmetric import ec, padding
from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes
from ...utils import raises_unsupported_algorithm
@utils.register_interface(CipherBackend)
class DummyCipherBackend(object):
def __init__(self, supported_ciphers):
self._ciphers = supported_ciphers
def cipher_supported(self, cipher, mode):
return (type(cipher), type(mode)) in self._ciphers
def create_symmetric_encryption_ctx(self, cipher, mode):
if not self.cipher_supported(cipher, mode):
raise UnsupportedAlgorithm("", _Reasons.UNSUPPORTED_CIPHER)
def create_symmetric_decryption_ctx(self, cipher, mode):
if not self.cipher_supported(cipher, mode):
raise UnsupportedAlgorithm("", _Reasons.UNSUPPORTED_CIPHER)
@utils.register_interface(HashBackend)
class DummyHashBackend(object):
def __init__(self, supported_algorithms):
self._algorithms = supported_algorithms
def hash_supported(self, algorithm):
return type(algorithm) in self._algorithms
def create_hash_ctx(self, algorithm):
if not self.hash_supported(algorithm):
raise UnsupportedAlgorithm("", _Reasons.UNSUPPORTED_HASH)
@utils.register_interface(HMACBackend)
class DummyHMACBackend(object):
def __init__(self, supported_algorithms):
self._algorithms = supported_algorithms
def hmac_supported(self, algorithm):
return type(algorithm) in self._algorithms
def create_hmac_ctx(self, key, algorithm):
if not self.hmac_supported(algorithm):
raise UnsupportedAlgorithm("", _Reasons.UNSUPPORTED_HASH)
@utils.register_interface(PBKDF2HMACBackend)
class DummyPBKDF2HMACBackend(object):
def __init__(self, supported_algorithms):
self._algorithms = supported_algorithms
def pbkdf2_hmac_supported(self, algorithm):
return type(algorithm) in self._algorithms
def derive_pbkdf2_hmac(self, algorithm, length, salt, iterations,
key_material):
if not self.pbkdf2_hmac_supported(algorithm):
raise UnsupportedAlgorithm("", _Reasons.UNSUPPORTED_HASH)
@utils.register_interface(RSABackend)
class DummyRSABackend(object):
def generate_rsa_private_key(self, public_exponent, key_size):
pass
def rsa_padding_supported(self, padding):
pass
def generate_rsa_parameters_supported(self, public_exponent, key_size):
pass
def load_rsa_private_numbers(self, numbers):
pass
def load_rsa_public_numbers(self, numbers):
pass
@utils.register_interface(DSABackend)
class DummyDSABackend(object):
def generate_dsa_parameters(self, key_size):
pass
def generate_dsa_private_key(self, parameters):
pass
def generate_dsa_private_key_and_parameters(self, key_size):
pass
def dsa_hash_supported(self, algorithm):
pass
def dsa_parameters_supported(self, p, q, g):
pass
def load_dsa_private_numbers(self, numbers):
pass
def load_dsa_public_numbers(self, numbers):
pass
def load_dsa_parameter_numbers(self, numbers):
pass
@utils.register_interface(CMACBackend)
class DummyCMACBackend(object):
def __init__(self, supported_algorithms):
self._algorithms = supported_algorithms
def cmac_algorithm_supported(self, algorithm):
return type(algorithm) in self._algorithms
def create_cmac_ctx(self, algorithm):
if not self.cmac_algorithm_supported(algorithm):
raise UnsupportedAlgorithm("", _Reasons.UNSUPPORTED_CIPHER)
@utils.register_interface(EllipticCurveBackend)
class DummyEllipticCurveBackend(object):
def __init__(self, supported_curves):
self._curves = supported_curves
def elliptic_curve_supported(self, curve):
return any(
isinstance(curve, curve_type)
for curve_type in self._curves
)
def elliptic_curve_signature_algorithm_supported(
self, signature_algorithm, curve
):
return (
isinstance(signature_algorithm, ec.ECDSA) and
self.elliptic_curve_supported(curve)
)
def generate_elliptic_curve_private_key(self, curve):
if not self.elliptic_curve_supported(curve):
raise UnsupportedAlgorithm(_Reasons.UNSUPPORTED_ELLIPTIC_CURVE)
def load_elliptic_curve_private_numbers(self, numbers):
if not self.elliptic_curve_supported(numbers.public_numbers.curve):
raise UnsupportedAlgorithm(_Reasons.UNSUPPORTED_ELLIPTIC_CURVE)
def load_elliptic_curve_public_numbers(self, numbers):
if not self.elliptic_curve_supported(numbers.curve):
raise UnsupportedAlgorithm(_Reasons.UNSUPPORTED_ELLIPTIC_CURVE)
def elliptic_curve_exchange_algorithm_supported(self, algorithm, curve):
return (
isinstance(algorithm, ec.ECDH) and
self.elliptic_curve_supported(curve)
)
@utils.register_interface(PEMSerializationBackend)
class DummyPEMSerializationBackend(object):
def load_pem_private_key(self, data, password):
pass
def load_pem_public_key(self, data):
pass
@utils.register_interface(DERSerializationBackend)
class DummyDERSerializationBackend(object):
def load_der_private_key(self, data, password):
pass
def load_der_public_key(self, data):
pass
@utils.register_interface(X509Backend)
class DummyX509Backend(object):
def load_pem_x509_certificate(self, data):
pass
def load_der_x509_certificate(self, data):
pass
def load_pem_x509_csr(self, data):
pass
def load_der_x509_csr(self, data):
pass
def create_x509_csr(self, builder, private_key, algorithm):
pass
def create_x509_certificate(self, builder, private_key, algorithm):
pass
class TestMultiBackend(object):
def test_ciphers(self):
backend = MultiBackend([
DummyHashBackend([]),
DummyCipherBackend([
(algorithms.AES, modes.CBC),
])
])
assert backend.cipher_supported(
algorithms.AES(b"\x00" * 16), modes.CBC(b"\x00" * 16)
)
assert not backend.cipher_supported(
algorithms.TripleDES(b"\x00" * 16), modes.CBC(b"\x00" * 16)
)
cipher = Cipher(
algorithms.AES(b"\x00" * 16),
modes.CBC(b"\x00" * 16),
backend=backend
)
cipher.encryptor()
cipher.decryptor()
cipher = Cipher(
algorithms.Camellia(b"\x00" * 16),
modes.CBC(b"\x00" * 16),
backend=backend
)
with raises_unsupported_algorithm(_Reasons.UNSUPPORTED_CIPHER):
cipher.encryptor()
with raises_unsupported_algorithm(_Reasons.UNSUPPORTED_CIPHER):
cipher.decryptor()
def test_hashes(self):
backend = MultiBackend([
DummyHashBackend([hashes.MD5])
])
assert backend.hash_supported(hashes.MD5())
assert not backend.hash_supported(hashes.SHA256())
hashes.Hash(hashes.MD5(), backend=backend)
with raises_unsupported_algorithm(_Reasons.UNSUPPORTED_HASH):
hashes.Hash(hashes.SHA1(), backend=backend)
def test_hmac(self):
backend = MultiBackend([
DummyHMACBackend([hashes.MD5])
])
assert backend.hmac_supported(hashes.MD5())
assert not backend.hmac_supported(hashes.SHA256())
hmac.HMAC(b"", hashes.MD5(), backend=backend)
with raises_unsupported_algorithm(_Reasons.UNSUPPORTED_HASH):
hmac.HMAC(b"", hashes.SHA1(), backend=backend)
def test_pbkdf2(self):
backend = MultiBackend([
DummyPBKDF2HMACBackend([hashes.MD5])
])
assert backend.pbkdf2_hmac_supported(hashes.MD5())
backend.derive_pbkdf2_hmac(hashes.MD5(), 10, b"", 10, b"")
with raises_unsupported_algorithm(_Reasons.UNSUPPORTED_HASH):
backend.derive_pbkdf2_hmac(hashes.SHA1(), 10, b"", 10, b"")
def test_rsa(self):
backend = MultiBackend([
DummyRSABackend()
])
backend.generate_rsa_private_key(
key_size=1024, public_exponent=65537
)
backend.rsa_padding_supported(padding.PKCS1v15())
backend.generate_rsa_parameters_supported(65537, 1024)
backend.load_rsa_private_numbers("private_numbers")
backend.load_rsa_public_numbers("public_numbers")
backend = MultiBackend([])
with raises_unsupported_algorithm(
_Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM
):
backend.generate_rsa_private_key(key_size=1024, public_exponent=3)
with raises_unsupported_algorithm(
_Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM
):
backend.rsa_padding_supported(padding.PKCS1v15())
with raises_unsupported_algorithm(
_Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM
):
backend.generate_rsa_parameters_supported(65537, 1024)
with raises_unsupported_algorithm(
_Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM
):
backend.load_rsa_private_numbers("private_numbers")
with raises_unsupported_algorithm(
_Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM
):
backend.load_rsa_public_numbers("public_numbers")
def test_dsa(self):
backend = MultiBackend([
DummyDSABackend()
])
backend.generate_dsa_parameters(key_size=1024)
parameters = object()
backend.generate_dsa_private_key(parameters)
backend.generate_dsa_private_key_and_parameters(key_size=1024)
backend.dsa_hash_supported(hashes.SHA1())
backend.dsa_parameters_supported(1, 2, 3)
backend.load_dsa_private_numbers("numbers")
backend.load_dsa_public_numbers("numbers")
backend.load_dsa_parameter_numbers("numbers")
backend = MultiBackend([])
with raises_unsupported_algorithm(
_Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM
):
backend.generate_dsa_parameters(key_size=1024)
with raises_unsupported_algorithm(
_Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM
):
backend.generate_dsa_private_key(parameters)
with raises_unsupported_algorithm(
_Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM
):
backend.generate_dsa_private_key_and_parameters(key_size=1024)
with raises_unsupported_algorithm(
_Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM
):
backend.dsa_hash_supported(hashes.SHA1())
with raises_unsupported_algorithm(
_Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM
):
backend.dsa_parameters_supported('p', 'q', 'g')
with raises_unsupported_algorithm(
_Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM
):
backend.load_dsa_private_numbers("numbers")
with raises_unsupported_algorithm(
_Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM
):
backend.load_dsa_public_numbers("numbers")
with raises_unsupported_algorithm(
_Reasons.UNSUPPORTED_PUBLIC_KEY_ALGORITHM
):
backend.load_dsa_parameter_numbers("numbers")
def test_cmac(self):
backend = MultiBackend([
DummyCMACBackend([algorithms.AES])
])
fake_key = b"\x00" * 16
assert backend.cmac_algorithm_supported(algorithms.AES(fake_key))
assert not backend.cmac_algorithm_supported(
algorithms.TripleDES(fake_key)
)
cmac.CMAC(algorithms.AES(fake_key), backend)
with raises_unsupported_algorithm(_Reasons.UNSUPPORTED_CIPHER):
cmac.CMAC(algorithms.TripleDES(fake_key), backend)
def test_elliptic_curve(self):
backend = MultiBackend([
DummyEllipticCurveBackend([
ec.SECT283K1
])
])
assert backend.elliptic_curve_supported(ec.SECT283K1()) is True
assert backend.elliptic_curve_signature_algorithm_supported(
ec.ECDSA(hashes.SHA256()),
ec.SECT283K1()
) is True
backend.generate_elliptic_curve_private_key(ec.SECT283K1())
backend.load_elliptic_curve_private_numbers(
ec.EllipticCurvePrivateNumbers(
1,
ec.EllipticCurvePublicNumbers(
2,
3,
ec.SECT283K1()
)
)
)
backend.load_elliptic_curve_public_numbers(
ec.EllipticCurvePublicNumbers(
2,
3,
ec.SECT283K1()
)
)
assert backend.elliptic_curve_supported(ec.SECT163K1()) is False
assert backend.elliptic_curve_signature_algorithm_supported(
ec.ECDSA(hashes.SHA256()),
ec.SECT163K1()
) is False
with raises_unsupported_algorithm(_Reasons.UNSUPPORTED_ELLIPTIC_CURVE):
backend.generate_elliptic_curve_private_key(ec.SECT163K1())
with raises_unsupported_algorithm(_Reasons.UNSUPPORTED_ELLIPTIC_CURVE):
backend.load_elliptic_curve_private_numbers(
ec.EllipticCurvePrivateNumbers(
1,
ec.EllipticCurvePublicNumbers(
2,
3,
ec.SECT163K1()
)
)
)
with raises_unsupported_algorithm(_Reasons.UNSUPPORTED_ELLIPTIC_CURVE):
backend.load_elliptic_curve_public_numbers(
ec.EllipticCurvePublicNumbers(
2,
3,
ec.SECT163K1()
)
)
assert backend.elliptic_curve_exchange_algorithm_supported(
ec.ECDH(), ec.SECT283K1()
)
backend2 = MultiBackend([DummyEllipticCurveBackend([])])
assert not backend2.elliptic_curve_exchange_algorithm_supported(
ec.ECDH(), ec.SECT163K1()
)
def test_pem_serialization_backend(self):
backend = MultiBackend([DummyPEMSerializationBackend()])
backend.load_pem_private_key(b"keydata", None)
backend.load_pem_public_key(b"keydata")
backend = MultiBackend([])
with raises_unsupported_algorithm(_Reasons.UNSUPPORTED_SERIALIZATION):
backend.load_pem_private_key(b"keydata", None)
with raises_unsupported_algorithm(_Reasons.UNSUPPORTED_SERIALIZATION):
backend.load_pem_public_key(b"keydata")
def test_der_serialization_backend(self):
backend = MultiBackend([DummyDERSerializationBackend()])
backend.load_der_private_key(b"keydata", None)
backend.load_der_public_key(b"keydata")
backend = MultiBackend([])
with raises_unsupported_algorithm(_Reasons.UNSUPPORTED_SERIALIZATION):
backend.load_der_private_key(b"keydata", None)
with raises_unsupported_algorithm(_Reasons.UNSUPPORTED_SERIALIZATION):
backend.load_der_public_key(b"keydata")
def test_x509_backend(self):
backend = MultiBackend([DummyX509Backend()])
backend.load_pem_x509_certificate(b"certdata")
backend.load_der_x509_certificate(b"certdata")
backend.load_pem_x509_csr(b"reqdata")
backend.load_der_x509_csr(b"reqdata")
backend.create_x509_csr(object(), b"privatekey", hashes.SHA1())
backend.create_x509_certificate(object(), b"privatekey", hashes.SHA1())
backend = MultiBackend([])
with raises_unsupported_algorithm(_Reasons.UNSUPPORTED_X509):
backend.load_pem_x509_certificate(b"certdata")
with raises_unsupported_algorithm(_Reasons.UNSUPPORTED_X509):
backend.load_der_x509_certificate(b"certdata")
with raises_unsupported_algorithm(_Reasons.UNSUPPORTED_X509):
backend.load_pem_x509_csr(b"reqdata")
with raises_unsupported_algorithm(_Reasons.UNSUPPORTED_X509):
backend.load_der_x509_csr(b"reqdata")
with raises_unsupported_algorithm(_Reasons.UNSUPPORTED_X509):
backend.create_x509_csr(object(), b"privatekey", hashes.SHA1())
with raises_unsupported_algorithm(_Reasons.UNSUPPORTED_X509):
backend.create_x509_certificate(
object(), b"privatekey", hashes.SHA1()
)
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