Source code for dispass.algos

'''Passphrase algorithms

The algos module is the most important part of DisPass. The algorithms
DisPass uses to create the passphrases are defined as separate classes
in this module.
'''

# Copyright (c) 2012-2016  Tom Willemse <tom@ryuslash.org>
# Copyright (c) 2011-2018  Benjamin Althues <benjamin@babab.nl>
#
# Permission to use, copy, modify, and distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

import base64
import hashlib

algorithms = ('dispass1', 'dispass2')
'''A tuple of registrered algorithms, used for validation of user input'''


[docs]def algoObject(algoname): '''Return an algorithm object :Parameters: - `algoname`: String. Name of the algorithm :Return: - An algorithm object or False ''' if algoname == 'dispass1': return Dispass1() elif algoname == 'dispass2': return Dispass2() else: return False
[docs]class Dispass1: '''Dispass1 algorithm Tests: >>> dispass1 = Dispass1() >>> dispass1.digest('test', 'qqqqqqqq') 'Y2Y4Y2Y0Yzg5Nzc1Yzc2MmI4OTU0ND' >>> dispass1.digest('test2', 'qqqqqqqq', 50) 'NmQzNjUzZTlhNTc4NWFlNTU5ZTVkZGQ5ZTc2NzliZjgzZDQ1Zj' '''
[docs] @staticmethod def digest(label, password, length=30, seqno=None): '''Create and return secure hash of message A secure hash/message digest formed by hashing a string (formed by concatenating label+password) with the sha512 algorithm, encoding this hash with base64 and stripping it down to the first `length` characters. :Parameters: - `label`: String. Labelname - `password`: String. The input password - `length`: Length of output hash (optional) - `seqno`: Sequence number. Not used in Dispass1 :Return: - The secure hash of `label` + `password` ''' sha = hashlib.sha512() sha.update(label.encode('utf-8') + password.encode('utf-8')) r = base64.b64encode(sha.hexdigest().encode('utf-8'), b'49') \ .replace(b'=', b'') return r[:length].decode()
[docs]class Dispass2: '''Dispass2 algorithm Tests: >>> dispass2 = Dispass2() >>> dispass2.digest('test', 'qqqqqqqq') 'ZTdiNGNkYmQ2ZjFmNzc3NGFjZWEwMz' >>> dispass2.digest('test2', 'qqqqqqqq', 50, 10) 'NGEwNjMxMzZiMzljODVmODk4OWQ1ZmE4YTRlY2E4ODZkZjZlZW' '''
[docs] @staticmethod def digest(label, password, length=30, seqno=1): '''Create and return secure hash of message A secure hash/message digest formed by hashing a string (formed by concatenating label+seqno+password) with the sha512 algorithm, encoding this hash with base64 and stripping it down to the first `length` characters. :Parameters: - `label`: String. Labelname - `password`: String. The input password - `length`: Length of output hash (optional) - `seqno`: Integer. Sequence number. :Return: - The secure hash of `label` + `seqno` + `password` ''' sha = hashlib.sha512() sha.update(label.encode('utf-8') + str(seqno).encode('utf-8') + password.encode('utf-8')) r = base64.b64encode(sha.hexdigest().encode('utf-8'), b'49') \ .replace(b'=', b'') return r[:length].decode()
if __name__ == '__main__': import doctest doctest.testmod()