57 lines
2.4 KiB
Python
57 lines
2.4 KiB
Python
# -*- coding: utf-8 -*-
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#
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# ===================================================================
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# The contents of this file are dedicated to the public domain. To
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# the extent that dedication to the public domain is not available,
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# everyone is granted a worldwide, perpetual, royalty-free,
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# non-exclusive license to exercise all rights associated with the
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# contents of this file for any purpose whatsoever.
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# No rights are reserved.
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#
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# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
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# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
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# BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
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# ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
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# CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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# SOFTWARE.
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# ===================================================================
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"""Hashing algorithms
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Hash functions take arbitrary binary strings as input, and produce a random-like output
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of fixed size that is dependent on the input; it should be practically infeasible
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to derive the original input data given only the hash function's
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output. In other words, the hash function is *one-way*.
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It should also not be practically feasible to find a second piece of data
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(a *second pre-image*) whose hash is the same as the original message
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(*weak collision resistance*).
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Finally, it should not be feasible to find two arbitrary messages with the
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same hash (*strong collision resistance*).
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The output of the hash function is called the *digest* of the input message.
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In general, the security of a hash function is related to the length of the
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digest. If the digest is *n* bits long, its security level is roughly comparable
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to the the one offered by an *n/2* bit encryption algorithm.
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Hash functions can be used simply as a integrity check, or, in
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association with a public-key algorithm, can be used to implement
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digital signatures.
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The hashing modules here all support the interface described in `PEP
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247`_ , "API for Cryptographic Hash Functions".
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.. _`PEP 247` : http://www.python.org/dev/peps/pep-0247/
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:undocumented: _MD2, _MD4, _RIPEMD160, _SHA224, _SHA256, _SHA384, _SHA512
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"""
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__all__ = ['HMAC', 'MD2', 'MD4', 'MD5', 'RIPEMD', 'SHA',
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'SHA224', 'SHA256', 'SHA384', 'SHA512']
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__revision__ = "$Id$"
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