1 class Security:

     2 

     3     def __init__(self):

     4         import os

     5         env = os.environ

     6         if env.has_key('PYTHON_KEYFILE'):

     7             keyfile = env['PYTHON_KEYFILE']

     8         else:

     9             keyfile = '.python_keyfile'

    10             if env.has_key('HOME'):

    11                 keyfile = os.path.join(env['HOME'], keyfile)

    12             if not os.path.exists(keyfile):

    13                 import sys

    14                 for dir in sys.path:

    15                     kf = os.path.join(dir, keyfile)

    16                     if os.path.exists(kf):

    17                         keyfile = kf

    18                         break

    19         try:

    20             self._key = eval(open(keyfile).readline())

    21         except IOError:

    22             raise IOError, "python keyfile %s: cannot open" % keyfile

    23 

    24     def _generate_challenge(self):

    25         import random

    26         return random.randint(100, 100000)

    27 

    28     def _compare_challenge_response(self, challenge, response):

    29         return self._encode_challenge(challenge) == response

    30 

    31     def _encode_challenge(self, challenge):

    32         p, m = self._key

    33         return pow(long(challenge), p, m)