circuitpython/docs/library/cryptolib.rst

41 lines
1.4 KiB
ReStructuredText

:mod:`cryptolib` -- cryptographic ciphers
=========================================
.. module:: cryptolib
:synopsis: cryptographic ciphers
Classes
-------
.. class:: aes
.. classmethod:: __init__(key, mode, [IV])
Initialize cipher object, suitable for encryption/decryption. Note:
after initialization, cipher object can be use only either for
encryption or decryption. Running decrypt() operation after encrypt()
or vice versa is not supported.
Parameters are:
* *key* is an encryption/decryption key (bytes-like).
* *mode* is:
* ``1`` (or ``cryptolib.MODE_ECB`` if it exists) for Electronic Code Book (ECB).
* ``2`` (or ``cryptolib.MODE_CBC`` if it exists) for Cipher Block Chaining (CBC).
* ``6`` (or ``cryptolib.MODE_CTR`` if it exists) for Counter mode (CTR).
* *IV* is an initialization vector for CBC mode.
* For Counter mode, *IV* is the initial value for the counter.
.. method:: encrypt(in_buf, [out_buf])
Encrypt *in_buf*. If no *out_buf* is given result is returned as a
newly allocated `bytes` object. Otherwise, result is written into
mutable buffer *out_buf*. *in_buf* and *out_buf* can also refer
to the same mutable buffer, in which case data is encrypted in-place.
.. method:: decrypt(in_buf, [out_buf])
Like `encrypt()`, but for decryption.