Exemple #1
0
  def _generateRandomID(
      self,
      c1 = constants.CRYPTO_CHALLENGE_C1,
      c2 = constants.CRYPTO_CHALLENGE_C2):
    """Generates the NodeID by solving two cryptographic puzzles."""
    # Solve the static cryptographic puzzle.
    rsaKey = None
    p = 0x1 # non-zero value
    pub = None

    randomStream = Crypto.Random.new().read
    while not util.hasNZeroBitPrefix(p, c1):
      rsaKey = Crypto.PublicKey.RSA.generate(constants.RSA_BITS, randomStream)
      pub = str(rsaKey.n) + str(rsaKey.e)
      p = util.hsh2int(Crypto.Hash.SHA.new(Crypto.Hash.SHA.new(pub).digest()))

    # created correct NodeID
    self.rsaKey = rsaKey
    nodeID = Crypto.Hash.SHA.new(pub)

    # Solve the dynamic cryptographic puzzle.
    p, x = 0x1, None

    while not util.hasNZeroBitPrefix(p, c2):
      x = util.bin2int(util.generateRandomString(constants.ID_LENGTH))
      # This is madness!
      p = util.hsh2int(
          Crypto.Hash.SHA.new(
              util.int2bin(
                  (util.hsh2int(nodeID) ^ x))))

    # Found a correct value of X and nodeID
    self.x = x
    return nodeID.digest()
Exemple #2
0
 def _verifyID(self, nodeID, x):
   '''Verifies if a user's ID has been generated using the '''
   p1 = util.hsh2int(Crypto.Hash.SHA.new(nodeID))
   p2 = util.hsh2int(Crypto.Hash.SHA.new(
       util.int2bin((util.bin2int(nodeID) ^ x))))
   # check preceeding c_i bits in P1 and P2 using sharesXPrefices.
   return (
       util.hasNZeroBitPrefix(p1, constants.CRYPTO_CHALLENGE_C1) and
       util.hasNZeroBitPrefix(p2, constants.CRYPTO_CHALLENGE_C2))