Fix token hashing with python 3

With python 3, hasher.update() must be called with byte encoding.
Hashing without encoding first in python 3 results in this error:

  TypeError: Unicode-objects must be encoded before hashing

Using byte encoding also works with python 2.7, so convert tokens
to bytes before hashing regardless of python version.

Change-Id: I837566c669565ed8c11dacbefc273dae3ff580bb
Closes-Bug: #1552443

openstack_auth/tests/tests.py

@@ -29,9 +29,7 @@ from keystoneclient.v2_0 import client as client_v2
 from keystoneclient.v3 import client as client_v3
 import mock
 from mox3 import mox
-import sys
 from testscenarios import load_tests_apply_scenarios  # noqa
-import unittest
 
 from openstack_auth import policy
 from openstack_auth.tests import data_v2
@@ -1165,7 +1163,6 @@ class UserTestCase(test.TestCase):
     def setUp(self):
         self.data = data_v3.generate_test_data(pki=True)
 
-    @unittest.skipIf(sys.version_info >= (3, 0), "Bug #1552443")
     def test_unscoped_token_is_none(self):
         created_token = user.Token(self.data.domain_scoped_access_info,
                                    unscoped_token=None)

openstack_auth/user.py

@@ -88,12 +88,12 @@ class Token(object):
             algorithm = getattr(settings, 'OPENSTACK_TOKEN_HASH_ALGORITHM',
                                 'md5')
             hasher = hashlib.new(algorithm)
-            hasher.update(self.id)
+            hasher.update(self.id.encode('utf-8'))
             self.id = hasher.hexdigest()
             # Only hash unscoped token if needed
             if self._is_pki_token(self.unscoped_token):
                 hasher = hashlib.new(algorithm)
-                hasher.update(self.unscoped_token)
+                hasher.update(self.unscoped_token.encode('utf-8'))
                 self.unscoped_token = hasher.hexdigest()
         self.expires = auth_ref.expires