Utilities
=========

.. module:: monocypher.utils


Generating Random Bytes
-----------------------

.. autofunction:: monocypher.utils.random


Constant-Time Comparisons
-------------------------

The following functions perform constant-time comparisons of :py:class:`~bytes`
objects of length 16, 32, and 64 respectively. They return ``True`` if they
are equal, and ``False`` otherwise.

.. autofunction:: monocypher.utils.crypto_verify16

.. autofunction:: monocypher.utils.crypto_verify32

.. autofunction:: monocypher.utils.crypto_verify64

.. code:: python

   from monocypher.utils import crypto_verify16
   crypto_verify16(b'a....a', b'a....a')


Copying Contexts
----------------

.. autofunction:: monocypher.utils.copy_context



Memory Wipe
-----------

.. autofunction:: monocypher.utils.crypto_wipe

   Wipe the given `buf` by filling it with zeros.
   Example::

       >>> buf = bytearray(b'abc')
       >>> crypto_wipe(buf)
       >>> buf
       bytearray(b'\x00\x00\x00')

   :param buf: Any writable object with the buffer protocol,
               e.g. :py:class:`bytearray` or :py:class:`array.array`.