| 0,0 → 1,94 |
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| """ crypto.passwords.passwordfactory |
| |
| Python classes to create and recover passwords. Currently contains |
| simple password generation. <need to merge the dictionary based pws> |
| |
| Copyright © (c) 2002 by Paul A. Lambert |
| Read LICENSE.txt for license information. |
| |
| August 14, 2002 |
| """ |
| |
| from random import Random |
| from sha import sha # the SHA1 algorithm for cryptographic hashing |
| from math import log, ceil |
| #from binascii_plus import b2a_p |
| |
| class PasswordFactory: |
| """ Make passwords using pseudo random seeds. |
| Also used to recover passwords by using same pwSeed. |
| If the seed is not saved, the password can not be recovered!! |
| """ |
| def __init__(self, pwFactorySeed, minSize=10, maxSize=10 ): |
| """ An abstract class to create passwords """ |
| self._factorySeed = pwFactorySeed |
| self.minSize = minSize |
| self.maxSize = maxSize |
| self.rand = Random( self._factorySeed ) |
| |
| def getPassword(self, pwSeed): |
| raise "MUST be overloaded" |
| |
| def __call__(self, pwSeed): |
| """ Create a new password as a 'call' """ |
| return self.getPassword(pwSeed) |
| |
| def entropy(self): |
| """ Calculate the security of the password generation as a power of 2 """ |
| total = 0 |
| for pwSize in range(self.minSize, self.maxSize+1): |
| total = total + self.passwordsForSize(pwSize) |
| return powof2( total ) |
| |
| def powof2(x): |
| """ Convert x to a power of 2 """ |
| return log(x)/log(2) |
| |
| class PasswordFactorySimple(PasswordFactory): |
| """ This class implements a very secure but simple selection of numbers and letters. |
| Some characters have been removed to prevent confusion between similar shapes |
| The removed characters are: (O,0,o), (l,1,I) , (u,v),(U,V) |
| """ |
| def __init__(self, pwFactorySeed, minSize=10, maxSize=10 ): |
| """ Initialize password generation """ |
| PasswordFactory.__init__(self, pwFactorySeed, minSize, maxSize ) |
| self.lettersReduced = 'abcdefghijkmnpqrstwxyzABCDEFGHJKLMNPQRSTWXYZ' |
| self.digitsReduced = '23456789' |
| self.specialCharacters = '#%*+$' |
| |
| def getPassword(self, pwSeed): |
| """ Create a new password from pwSeed. """ |
| self.rand.seed( pwSeed + 'getPassword' + self._factorySeed ) # reset prf sequence |
| self.passwordSize = self.rand.randrange(self.minSize, self.maxSize+1) |
| password = '' |
| for i in range(self.passwordSize): |
| password = password + self.rand.choice(self.lettersReduced+self.digitsReduced) |
| return password |
| |
| def passwordsForSize(self,pwSize): |
| return (len(self.lettersReduced)+len(self.digitsReduced))**pwSize |
| |
| consonants_01 = 'bcdfghjklmnpqrstvwxz' |
| vowels_01 = 'aeiouy' |
| class PasswordFactoryReadable_01(PasswordFactory): |
| """ Readable passwords created by alternating consonate/vowel/consonate ... etc. |
| """ |
| def getPassword(self, pwSeed): |
| """ Create a new password. Also used to recover passwords by using same pwSeed """ |
| #self.rand.seed( 'getPassword'+self.__factorySeed+pwSeed ) # reset prf sequence |
| self.passwordSize = self.rand.randrange(self.minSize, self.maxSize+1) |
| password = '' |
| for i in range(self.passwordSize): |
| if i == 0 : |
| password = password + self.rand.choice(consonants_01) |
| else: |
| if password[-1] in consonants_01 : |
| password = password + self.rand.choice(vowels_01) |
| else: |
| password = password + self.rand.choice(consonants_01) |
| return password |
| |
| def passwordsForSize(self,pwSize): |
| return (len(vowels_01)**(pwSize/2))*(len(consonants_01)**ceil(pwSize/2)) |
| |
| |