gnuviechadmin-historic/gnuviechadmin/util/passwordutils.py

# -*- coding: utf-8 -*-
#
# Copyright (C) 2007 by Jan Dittberner.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
# USA.
#
# Version: $Id$

import crypt, crack, random

_pwchars = []
for pair in (('0', '9'), ('A', 'Z'), ('a', 'z')):
    _pwchars.extend(range(ord(pair[0]), ord(pair[1])))
_saltchars = [char for char in _pwchars]
for char in "-+/*_@":
    _pwchars.append(ord(char))

def generatepassword(minlength = 8, maxlength = 12):
    """Generates a random password with a length between the given
    minlength and maxlength values."""
    return "".join([chr(letter) for letter in \
                    random.sample(_pwchars,
                                  random.randint(minlength, maxlength))])

def checkpassword(password):
    """Checks the password with cracklib. The password is returned if
    it is good enough. Otherwise None is returned."""
    try:
        return crack.VeryFascistCheck(password)
    except ValueError, ve:
        print "Weak password:", ve
    return None
    
def md5_crypt_password(password):
    """Hashes the given password with MD5 and a random salt value."""
    salt = "".join([chr(letter) for letter in \
                    random.sample(_saltchars, 8)])
    return crypt.crypt(password, '$1$' + salt)

def get_pw_tuple(password = None):
    """Gets a valid tuple consisting of a password and a md5 hash of the
    password. If a password is given it is checked and if it is too weak
    replaced by a generated one."""
    while password == None or checkpassword(password) == None:
        password = generatepassword()
    return (password, md5_crypt_password(password))