# -*- coding: utf-8 -*- # # =================================================================== # The contents of this file are dedicated to the public domain. To # the extent that dedication to the public domain is not available, # everyone is granted a worldwide, perpetual, royalty-free, # non-exclusive license to exercise all rights associated with the # contents of this file for any purpose whatsoever. # No rights are reserved. # # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, # EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF # MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND # NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS # BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN # ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN # CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE # SOFTWARE. # =================================================================== """Hashing algorithms Hash functions take arbitrary binary strings as input, and produce a random-like output of fixed size that is dependent on the input; it should be practically infeasible to derive the original input data given only the hash function's output. In other words, the hash function is *one-way*. It should also not be practically feasible to find a second piece of data (a *second pre-image*) whose hash is the same as the original message (*weak collision resistance*). Finally, it should not be feasible to find two arbitrary messages with the same hash (*strong collision resistance*). The output of the hash function is called the *digest* of the input message. In general, the security of a hash function is related to the length of the digest. If the digest is *n* bits long, its security level is roughly comparable to the the one offered by an *n/2* bit encryption algorithm. Hash functions can be used simply as a integrity check, or, in association with a public-key algorithm, can be used to implement digital signatures. :undocumented: _MD2, _MD4, _RIPEMD160, _SHA224, _SHA256, _SHA384, _SHA512, _RIPEMD """ __all__ = ['HMAC', 'MD2', 'MD4', 'MD5', 'RIPEMD160', 'SHA1', 'SHA224', 'SHA256', 'SHA384', 'SHA512', 'CMAC']