diff options
| -rw-r--r-- | cryptography/hazmat/bindings/openssl/backend.py | 4 | ||||
| -rw-r--r-- | tests/hazmat/bindings/test_openssl.py | 20 |
2 files changed, 21 insertions, 3 deletions
diff --git a/cryptography/hazmat/bindings/openssl/backend.py b/cryptography/hazmat/bindings/openssl/backend.py index 7367818a..ea1073b9 100644 --- a/cryptography/hazmat/bindings/openssl/backend.py +++ b/cryptography/hazmat/bindings/openssl/backend.py @@ -147,7 +147,9 @@ class _CipherContext(object): raise UnsupportedAlgorithm evp_cipher = adapter(self._backend, cipher, mode) - assert evp_cipher != self._backend.ffi.NULL + if evp_cipher == self._backend.ffi.NULL: + raise UnsupportedAlgorithm + if isinstance(mode, interfaces.ModeWithInitializationVector): iv_nonce = mode.initialization_vector elif isinstance(mode, interfaces.ModeWithNonce): diff --git a/tests/hazmat/bindings/test_openssl.py b/tests/hazmat/bindings/test_openssl.py index fb01c10a..3523fa4e 100644 --- a/tests/hazmat/bindings/test_openssl.py +++ b/tests/hazmat/bindings/test_openssl.py @@ -11,11 +11,15 @@ # See the License for the specific language governing permissions and # limitations under the License. +import binascii + import pytest +from cryptography.exceptions import UnsupportedAlgorithm from cryptography.hazmat.bindings.openssl.backend import backend, Backend -from cryptography.hazmat.primitives.block.ciphers import AES -from cryptography.hazmat.primitives.block.modes import CBC +from cryptography.hazmat.primitives.block import BlockCipher +from cryptography.hazmat.primitives.block.ciphers import AES, TripleDES +from cryptography.hazmat.primitives.block.modes import CBC, ECB class TestOpenSSL(object): @@ -44,3 +48,15 @@ class TestOpenSSL(object): b = Backend() assert b.ffi is backend.ffi assert b.lib is backend.lib + + def test_nonexistent_cipher(self): + b = Backend() + # TODO: this test assumes that 3DES-ECB doesn't exist + b.ciphers.register_cipher_adapter( + TripleDES, ECB, lambda backend, cipher, mode: backend.ffi.NULL + ) + cipher = BlockCipher( + TripleDES(binascii.unhexlify(b"0" * 16)), ECB(), backend=b + ) + with pytest.raises(UnsupportedAlgorithm): + cipher.encryptor() |