Remove the review bot app.

reviewbot/third_party/google-api-python-client/oauth2client/xsrfutil.py

-#!/usr/bin/python2.5
-#
-# Copyright 2010 the Melange authors.
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#   http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-"""Helper methods for creating & verifying XSRF tokens."""
-
-__authors__ = [
-  '"Doug Coker" <dcoker@google.com>',
-  '"Joe Gregorio" <jcgregorio@google.com>',
-]
-
-
-import base64
-import hmac
-import os  # for urandom
-import time
-
-from oauth2client import util
-
-
-# Delimiter character
-DELIMITER = ':'
-
-# 1 hour in seconds
-DEFAULT_TIMEOUT_SECS = 1*60*60
-
-@util.positional(2)
-def generate_token(key, user_id, action_id="", when=None):
-  """Generates a URL-safe token for the given user, action, time tuple.
-
-  Args:
-    key: secret key to use.
-    user_id: the user ID of the authenticated user.
-    action_id: a string identifier of the action they requested
-      authorization for.
-    when: the time in seconds since the epoch at which the user was
-      authorized for this action. If not set the current time is used.
-
-  Returns:
-    A string XSRF protection token.
-  """
-  when = when or int(time.time())
-  digester = hmac.new(key)
-  digester.update(str(user_id))
-  digester.update(DELIMITER)
-  digester.update(action_id)
-  digester.update(DELIMITER)
-  digester.update(str(when))
-  digest = digester.digest()
-
-  token = base64.urlsafe_b64encode('%s%s%d' % (digest,
-                                               DELIMITER,
-                                               when))
-  return token
-
-
-@util.positional(3)
-def validate_token(key, token, user_id, action_id="", current_time=None):
-  """Validates that the given token authorizes the user for the action.
-
-  Tokens are invalid if the time of issue is too old or if the token
-  does not match what generateToken outputs (i.e. the token was forged).
-
-  Args:
-    key: secret key to use.
-    token: a string of the token generated by generateToken.
-    user_id: the user ID of the authenticated user.
-    action_id: a string identifier of the action they requested
-      authorization for.
-
-  Returns:
-    A boolean - True if the user is authorized for the action, False
-    otherwise.
-  """
-  if not token:
-    return False
-  try:
-    decoded = base64.urlsafe_b64decode(str(token))
-    token_time = long(decoded.split(DELIMITER)[-1])
-  except (TypeError, ValueError):
-    return False
-  if current_time is None:
-    current_time = time.time()
-  # If the token is too old it's not valid.
-  if current_time - token_time > DEFAULT_TIMEOUT_SECS:
-    return False
-
-  # The given token should match the generated one with the same time.
-  expected_token = generate_token(key, user_id, action_id=action_id,
-                                  when=token_time)
-  if len(token) != len(expected_token):
-    return False
-
-  # Perform constant time comparison to avoid timing attacks
-  different = 0
-  for x, y in zip(token, expected_token):
-    different |= ord(x) ^ ord(y)
-  if different:
-    return False
-
-  return True