mirror of
https://github.com/python/cpython.git
synced 2025-10-31 05:31:20 +00:00
58 lines
1.9 KiB
ReStructuredText
58 lines
1.9 KiB
ReStructuredText
:mod:`hmac` --- Keyed-Hashing for Message Authentication
|
|
========================================================
|
|
|
|
.. module:: hmac
|
|
:synopsis: Keyed-Hashing for Message Authentication (HMAC) implementation
|
|
for Python.
|
|
.. moduleauthor:: Gerhard Häring <ghaering@users.sourceforge.net>
|
|
.. sectionauthor:: Gerhard Häring <ghaering@users.sourceforge.net>
|
|
|
|
**Source code:** :source:`Lib/hmac.py`
|
|
|
|
--------------
|
|
|
|
This module implements the HMAC algorithm as described by :rfc:`2104`.
|
|
|
|
|
|
.. function:: new(key, msg=None, digestmod=None)
|
|
|
|
Return a new hmac object. *key* is a bytes object giving the secret key. If
|
|
*msg* is present, the method call ``update(msg)`` is made. *digestmod* is
|
|
the digest constructor or module for the HMAC object to use. It defaults to
|
|
the :func:`hashlib.md5` constructor.
|
|
|
|
|
|
An HMAC object has the following methods:
|
|
|
|
.. method:: hmac.update(msg)
|
|
|
|
Update the hmac object with the bytes object *msg*. Repeated calls are
|
|
equivalent to a single call with the concatenation of all the arguments:
|
|
``m.update(a); m.update(b)`` is equivalent to ``m.update(a + b)``.
|
|
|
|
|
|
.. method:: hmac.digest()
|
|
|
|
Return the digest of the bytes passed to the :meth:`update` method so far.
|
|
This bytes object will be the same length as the *digest_size* of the digest
|
|
given to the constructor. It may contain non-ASCII bytes, including NUL
|
|
bytes.
|
|
|
|
|
|
.. method:: hmac.hexdigest()
|
|
|
|
Like :meth:`digest` except the digest is returned as a string twice the
|
|
length containing only hexadecimal digits. This may be used to exchange the
|
|
value safely in email or other non-binary environments.
|
|
|
|
|
|
.. method:: hmac.copy()
|
|
|
|
Return a copy ("clone") of the hmac object. This can be used to efficiently
|
|
compute the digests of strings that share a common initial substring.
|
|
|
|
|
|
.. seealso::
|
|
|
|
Module :mod:`hashlib`
|
|
The Python module providing secure hash functions.
|