diff options
Diffstat (limited to 'docs/hazmat/backends/interfaces.rst')
| -rw-r--r-- | docs/hazmat/backends/interfaces.rst | 68 |
1 files changed, 45 insertions, 23 deletions
diff --git a/docs/hazmat/backends/interfaces.rst b/docs/hazmat/backends/interfaces.rst index 5b6cd64d..49e4c88c 100644 --- a/docs/hazmat/backends/interfaces.rst +++ b/docs/hazmat/backends/interfaces.rst @@ -33,30 +33,11 @@ A specific ``backend`` may provide one or more of these interfaces. :returns: ``True`` if the specified ``cipher`` and ``mode`` combination is supported by this backend, otherwise ``False`` - .. method:: register_cipher_adapter(cipher_cls, mode_cls, adapter) - - Register an adapter which can be used to create a backend specific - object from instances of the - :class:`~cryptography.hazmat.primitives.interfaces.CipherAlgorithm` and - the :class:`~cryptography.hazmat.primitives.interfaces.Mode` primitives. - - :param cipher_cls: A class whose instances provide - :class:`~cryptography.hazmat.primitives.interfaces.CipherAlgorithm` - :param mode_cls: A class whose instances provide: - :class:`~cryptography.hazmat.primitives.interfaces.Mode` - :param adapter: A ``function`` that takes 3 arguments, ``backend`` (a - :class:`CipherBackend` provider), ``cipher`` (a - :class:`~cryptography.hazmat.primitives.interfaces.CipherAlgorithm` - provider ), and ``mode`` (a - :class:`~cryptography.hazmat.primitives.interfaces.Mode` provider). - It returns a backend specific object which may be used to construct - a :class:`~cryptogrpahy.hazmat.primitives.interfaces.CipherContext`. - .. method:: create_symmetric_encryption_ctx(cipher, mode) Create a - :class:`~cryptogrpahy.hazmat.primitives.interfaces.CipherContext` that + :class:`~cryptography.hazmat.primitives.interfaces.CipherContext` that can be used for encrypting data with the symmetric ``cipher`` using the given ``mode``. @@ -75,7 +56,7 @@ A specific ``backend`` may provide one or more of these interfaces. .. method:: create_symmetric_decryption_ctx(cipher, mode) Create a - :class:`~cryptogrpahy.hazmat.primitives.interfaces.CipherContext` that + :class:`~cryptography.hazmat.primitives.interfaces.CipherContext` that can be used for decrypting data with the symmetric ``cipher`` using the given ``mode``. @@ -110,7 +91,7 @@ A specific ``backend`` may provide one or more of these interfaces. .. method:: create_hash_ctx(algorithm) Create a - :class:`~cryptogrpahy.hazmat.primitives.interfaces.HashContext` that + :class:`~cryptography.hazmat.primitives.interfaces.HashContext` that uses the specified ``algorithm`` to calculate a message digest. :param algorithm: An instance of a @@ -140,7 +121,7 @@ A specific ``backend`` may provide one or more of these interfaces. .. method:: create_hmac_ctx(algorithm) Create a - :class:`~cryptogrpahy.hazmat.primitives.interfaces.HashContext` that + :class:`~cryptography.hazmat.primitives.interfaces.HashContext` that uses the specified ``algorithm`` to calculate a hash-based message authentication code. @@ -150,3 +131,44 @@ A specific ``backend`` may provide one or more of these interfaces. :returns: :class:`~cryptography.hazmat.primitives.interfaces.HashContext` + + +.. class:: PBKDF2HMACBackend + + .. versionadded:: 0.2 + + A backend with methods for using PBKDF2 using HMAC as a PRF. + + .. method:: pbkdf2_hmac_supported(algorithm) + + Check if the specified ``algorithm`` is supported by this backend. + + :param algorithm: An instance of a + :class:`~cryptography.hazmat.primitives.interfaces.HashAlgorithm` + provider. + + :returns: ``True`` if the specified ``algorithm`` is supported for + PBKDF2 HMAC by this backend, otherwise ``False``. + + .. method:: derive_pbkdf2_hmac(self, algorithm, length, salt, iterations, + key_material) + + :param algorithm: An instance of a + :class:`~cryptography.hazmat.primitives.interfaces.HashAlgorithm` + provider. + + :param int length: The desired length of the derived key. Maximum is + (2\ :sup:`32` - 1) * ``algorithm.digest_size`` + + :param bytes salt: A salt. + + :param int iterations: The number of iterations to perform of the hash + function. This can be used to control the length of time the + operation takes. Higher numbers help mitigate brute force attacks + against derived keys. + + :param bytes key_material: The key material to use as a basis for + the derived key. This is typically a password. + + :return bytes: Derived key. + |