ref: 5fc5c18208546c77f2c279f7f6acf6b01a2d2645
dir: /sys/src/cmd/python/Demo/pdist/security.py/
class Security: def __init__(self): import os env = os.environ if env.has_key('PYTHON_KEYFILE'): keyfile = env['PYTHON_KEYFILE'] else: keyfile = '.python_keyfile' if env.has_key('HOME'): keyfile = os.path.join(env['HOME'], keyfile) if not os.path.exists(keyfile): import sys for dir in sys.path: kf = os.path.join(dir, keyfile) if os.path.exists(kf): keyfile = kf break try: self._key = eval(open(keyfile).readline()) except IOError: raise IOError, "python keyfile %s: cannot open" % keyfile def _generate_challenge(self): import random return random.randint(100, 100000) def _compare_challenge_response(self, challenge, response): return self._encode_challenge(challenge) == response def _encode_challenge(self, challenge): p, m = self._key return pow(long(challenge), p, m)