diff options
| -rw-r--r-- | cryptography/hazmat/primitives/padding.py | 9 | ||||
| -rw-r--r-- | docs/hazmat/primitives/padding.rst | 9 | ||||
| -rw-r--r-- | tests/hazmat/primitives/test_padding.py | 9 |
3 files changed, 19 insertions, 8 deletions
diff --git a/cryptography/hazmat/primitives/padding.py b/cryptography/hazmat/primitives/padding.py index d78c6a5b..c1a763b5 100644 --- a/cryptography/hazmat/primitives/padding.py +++ b/cryptography/hazmat/primitives/padding.py @@ -20,6 +20,7 @@ import cffi import six from cryptography import utils +from cryptography.exceptions import AlreadyFinalized from cryptography.hazmat.bindings.utils import _create_modulename from cryptography.hazmat.primitives import interfaces @@ -101,7 +102,7 @@ class _PKCS7PaddingContext(object): def update(self, data): if self._buffer is None: - raise ValueError("Context was already finalized") + raise AlreadyFinalized("Context was already finalized") if isinstance(data, six.text_type): raise TypeError("Unicode-objects must be encoded before padding") @@ -117,7 +118,7 @@ class _PKCS7PaddingContext(object): def finalize(self): if self._buffer is None: - raise ValueError("Context was already finalized") + raise AlreadyFinalized("Context was already finalized") pad_size = self.block_size // 8 - len(self._buffer) result = self._buffer + six.int2byte(pad_size) * pad_size @@ -134,7 +135,7 @@ class _PKCS7UnpaddingContext(object): def update(self, data): if self._buffer is None: - raise ValueError("Context was already finalized") + raise AlreadyFinalized("Context was already finalized") if isinstance(data, six.text_type): raise TypeError("Unicode-objects must be encoded before unpadding") @@ -153,7 +154,7 @@ class _PKCS7UnpaddingContext(object): def finalize(self): if self._buffer is None: - raise ValueError("Context was already finalized") + raise AlreadyFinalized("Context was already finalized") if len(self._buffer) != self.block_size // 8: raise ValueError("Invalid padding bytes") diff --git a/docs/hazmat/primitives/padding.rst b/docs/hazmat/primitives/padding.rst index c0209446..3056eb92 100644 --- a/docs/hazmat/primitives/padding.rst +++ b/docs/hazmat/primitives/padding.rst @@ -66,7 +66,16 @@ multiple of the block size. :param bytes data: The data you wish to pass into the context. :return bytes: Returns the data that was padded or unpadded. + :raises cryptography.exceptions.AlreadyFinalized: See :meth:`finalize`. .. method:: finalize() + Finalize the current context and return the rest of the data. + + After ``finalize`` has been called this object can no longer be used; + :meth:`update` and :meth:`finalize` will raise an + :class:`~cryptography.exceptions.AlreadyFinalized` exception. + :return bytes: Returns the remainder of the data. + :raises ValueError: When trying to remove padding from incorrectly + padded data. diff --git a/tests/hazmat/primitives/test_padding.py b/tests/hazmat/primitives/test_padding.py index 932cef1e..cac54f27 100644 --- a/tests/hazmat/primitives/test_padding.py +++ b/tests/hazmat/primitives/test_padding.py @@ -17,6 +17,7 @@ import pytest import six +from cryptography.exceptions import AlreadyFinalized from cryptography.hazmat.primitives import padding @@ -97,15 +98,15 @@ class TestPKCS7(object): def test_use_after_finalize(self): padder = padding.PKCS7(128).padder() b = padder.finalize() - with pytest.raises(ValueError): + with pytest.raises(AlreadyFinalized): padder.update(b"") - with pytest.raises(ValueError): + with pytest.raises(AlreadyFinalized): padder.finalize() unpadder = padding.PKCS7(128).unpadder() unpadder.update(b) unpadder.finalize() - with pytest.raises(ValueError): + with pytest.raises(AlreadyFinalized): unpadder.update(b"") - with pytest.raises(ValueError): + with pytest.raises(AlreadyFinalized): unpadder.finalize() |