diff options
Diffstat (limited to 'cryptography/primitives/block/base.py')
| -rw-r--r-- | cryptography/primitives/block/base.py | 17 |
1 files changed, 12 insertions, 5 deletions
diff --git a/cryptography/primitives/block/base.py b/cryptography/primitives/block/base.py index 207c83d9..2018138c 100644 --- a/cryptography/primitives/block/base.py +++ b/cryptography/primitives/block/base.py @@ -12,9 +12,16 @@ # limitations under the License. # TODO: which binding is used should be an option somewhere +from enum import Enum + from cryptography.bindings.openssl import api +class _Operation(Enum): + encrypt = "encrypt" + decrypt = "decrypt" + + class BlockCipher(object): def __init__(self, cipher, mode): super(BlockCipher, self).__init__() @@ -34,10 +41,10 @@ class BlockCipher(object): raise ValueError("BlockCipher was already finalized") if self._operation is None: - self._operation = "encrypt" - elif self._operation != "encrypt": + self._operation = _Operation.encrypt + elif self._operation is not _Operation.encrypt: raise ValueError("BlockCipher cannot encrypt when the operation is" - " set to %s" % self._operation) + " set to %s" % self._operation.name) return api.update_encrypt_context(self._ctx, plaintext) @@ -45,11 +52,11 @@ class BlockCipher(object): if self._ctx is None: raise ValueError("BlockCipher was already finalized") - if self._operation == "encrypt": + if self._operation is _Operation.encrypt: result = api.finalize_encrypt_context(self._ctx) else: raise ValueError("BlockCipher cannot finalize the unknown " - "operation %s" % self._operation) + "operation %s" % self._operation.name) self._ctx = None return result |