blocksize: key = self.digest_cons(key).digest() key = key + chr(0) * (blocksize - len(key)) self.outer.update(key.translate(trans_5C)) self.inner.update(key.translate(trans_36)) if msg is not None: self.update(msg) ## def clear(self): ## raise NotImplementedError, "clear() method not available in HMAC." def update(self, msg): """Update this hashing object with the string msg. """ self.inner.update(msg) def copy(self): """Return a separate copy of this hashing object. An update to this copy won't affect the original object. """ other = self.__class__(_secret_backdoor_key) other.digest_cons = self.digest_cons other.digest_size = self.digest_size other.inner = self.inner.copy() other.outer = self.outer.copy() return other def _current(self): """Return a hash object for the current state. To be used only internally with digest() and hexdigest(). """ h = self.outer.copy() h.update(self.inner.digest()) return h def digest(self): """Return the hash value of this hashing object. This returns a string containing 8-bit data. The object is not altered in any way by this function; you can continue updating the object after calling this function. """ h = self._current() return h.digest() def hexdigest(self): """Like digest(), but returns a string of hexadecimal digits instead. """ h = self._current() return h.hexdigest() def new(key, msg = None, digestmod = None): """Create a new hashing object and return it. key: The starting key for the hash. msg: if available, will immediately be hashed into the object's starting state. You can now feed arbitrary strings into the object using its update() method, and can ask for the hash value at any time by calling its digest() method. """ return HMAC(key, msg, digestmod)