l4/pkg/python/contrib/Demo/pdist/security.py

   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)