/Doc/library/hmac.rst
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- :mod:`hmac` --- Keyed-Hashing for Message Authentication
- ========================================================
- .. module:: hmac
- :synopsis: Keyed-Hashing for Message Authentication (HMAC) implementation for Python.
- .. moduleauthor:: Gerhard H채ring <ghaering@users.sourceforge.net>
- .. sectionauthor:: Gerhard H채ring <ghaering@users.sourceforge.net>
- .. versionadded:: 2.2
- This module implements the HMAC algorithm as described by :rfc:`2104`.
- .. function:: new(key[, msg[, digestmod]])
- Return a new hmac object. 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.
- .. note::
- The md5 hash has known weaknesses but remains the default for backwards
- compatibility. Choose a better one for your application.
- An HMAC object has the following methods:
- .. method:: hmac.update(msg)
- Update the hmac object with the string *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 strings passed to the :meth:`update` method so far.
- This string will be the same length as the *digest_size* of the digest given to
- the constructor. It may contain non-ASCII characters, 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.