Hash authentication tokens before storing in the database.

pillar/__init__.py

@@ -91,6 +91,7 @@ class PillarServer(Eve):
         self.log = logging.getLogger('%s.%s' % (__name__, self.__class__.__name__))
         self.log.info('Creating new instance from %r', self.app_root)
 
+        self._config_auth_token_hmac_key()
         self._config_tempdirs()
         self._config_git()
         self._config_bugsnag()
@@ -149,6 +150,18 @@ class PillarServer(Eve):
         if self.config['DEBUG']:
             log.info('Pillar starting, debug=%s', self.config['DEBUG'])
 
+    def _config_auth_token_hmac_key(self):
+        """Load AUTH_TOKEN_HMAC_KEY, falling back to SECRET_KEY."""
+
+        hmac_key = self.config.get('AUTH_TOKEN_HMAC_KEY')
+        if not hmac_key:
+            self.log.warning('AUTH_TOKEN_HMAC_KEY not set, falling back to SECRET_KEY')
+            hmac_key = self.config['AUTH_TOKEN_HMAC_KEY'] = self.config['SECRET_KEY']
+
+        if isinstance(hmac_key, str):
+            self.log.warning('Converting AUTH_TOKEN_HMAC_KEY to bytes')
+            self.config['AUTH_TOKEN_HMAC_KEY'] = hmac_key.encode('utf8')
+
     def _config_tempdirs(self):
         storage_dir = self.config['STORAGE_DIR']
         if not os.path.exists(storage_dir):

pillar/api/eve_settings.py

@@ -320,6 +320,10 @@ tokens_schema = {
         'required': True,
     },
     'token': {
+        'type': 'string',
+        'required': False,
+    },
+    'token_hashed': {
         'type': 'string',
         'required': True,
     },

pillar/api/local_auth.py

@@ -72,13 +72,16 @@ def make_token():
     return jsonify(token=token['token'])
 
 
-def generate_and_store_token(user_id, days=15, prefix=b''):
+def generate_and_store_token(user_id, days=15, prefix=b'') -> dict:
     """Generates token based on random bits.
 
+    NOTE: the returned document includes the plain-text token.
+    DO NOT STORE OR LOG THIS unless there is a good reason to.
+
     :param user_id: ObjectId of the owning user.
     :param days: token will expire in this many days.
     :param prefix: the token will be prefixed by these bytes, for easy identification.
-    :return: the token document.
+    :return: the token document with the token in plain text as well as hashed.
     """
 
     if not isinstance(prefix, bytes):
@@ -90,10 +93,17 @@ def generate_and_store_token(user_id, days=15, prefix=b''):
 
     # Use 'xy' as altargs to prevent + and / characters from appearing.
     # We never have to b64decode the string anyway.
-    token = prefix + base64.b64encode(random_bits, altchars=b'xy').strip(b'=')
+    token_bytes = prefix + base64.b64encode(random_bits, altchars=b'xy').strip(b'=')
+    token = token_bytes.decode('ascii')
 
     token_expiry = datetime.datetime.now(tz=tz_util.utc) + datetime.timedelta(days=days)
-    return store_token(user_id, token.decode('ascii'), token_expiry)
+    token_data = store_token(user_id, token, token_expiry)
+
+    # Include the token in the returned document so that it can be stored client-side,
+    # in configuration, etc.
+    token_data['token'] = token
+
+    return token_data
 
 
 def hash_password(password: str, salt: typing.Union[str, bytes]) -> str:

pillar/api/utils/authentication.py

@@ -5,7 +5,10 @@ unique usernames from emails. Calls out to the pillar_server.modules.blender_id
 module for Blender ID communication.
 """
 
+import base64
 import datetime
+import hmac
+import hashlib
 import logging
 import typing
 
@@ -181,8 +184,10 @@ def find_token(token, is_subclient_token=False, **extra_filters):
 
     tokens_collection = current_app.data.driver.db['tokens']
 
-    # TODO: remove expired tokens from collection.
+    token_hashed = hash_auth_token(token)
-    lookup = {'token': token,
+
+    # TODO: remove matching on unhashed tokens once all tokens have been hashed.
+    lookup = {'$or': [{'token': token}, {'token_hashed': token_hashed}],
               'is_subclient_token': True if is_subclient_token else {'$in': [False, None]},
               'expire_time': {"$gt": datetime.datetime.now(tz=tz_util.utc)}}
     lookup.update(extra_filters)
@@ -191,6 +196,19 @@ def find_token(token, is_subclient_token=False, **extra_filters):
     return db_token
 
 
+def hash_auth_token(token: str) -> str:
+    """Returns the hashed authentication token.
+
+    The token is hashed using HMAC and then base64-encoded.
+    """
+
+    hmac_key = current_app.config['AUTH_TOKEN_HMAC_KEY']
+    token_hmac = hmac.new(hmac_key, msg=token.encode('utf8'), digestmod=hashlib.sha256)
+    digest = token_hmac.digest()
+
+    return base64.b64encode(digest).decode('ascii')
+
+
 def store_token(user_id, token: str, token_expiry, oauth_subclient_id=False):
     """Stores an authentication token.
 
@@ -201,7 +219,7 @@ def store_token(user_id, token: str, token_expiry, oauth_subclient_id=False):
 
     token_data = {
         'user': user_id,
-        'token': token,
+        'token_hashed': hash_auth_token(token),
         'expire_time': token_expiry,
     }
     if oauth_subclient_id:

pillar/config.py

@@ -24,6 +24,9 @@ DEBUG = False
 # python3 -c 'import secrets; print(secrets.token_urlsafe(128))'
 SECRET_KEY = ''
 
+# Authentication token hashing key. If empty falls back to UTF8-encoded SECRET_KEY with a warning.
+AUTH_TOKEN_HMAC_KEY = b''
+
 # Authentication settings
 BLENDER_ID_ENDPOINT = 'http://blender_id:8000/'
 

tests/test_api/test_auth.py

@@ -78,6 +78,8 @@ class AuthenticationTests(AbstractPillarTest):
 
         from pillar.api.utils import authentication as auth
 
+        self.enter_app_context()
+
         user_id = self.create_user()
 
         now = datetime.datetime.now(tz_util.utc)
@@ -85,11 +87,16 @@ class AuthenticationTests(AbstractPillarTest):
         past = now - datetime.timedelta(days=1)
         subclient = self.app.config['BLENDER_ID_SUBCLIENT_ID']
 
-        with self.app.test_request_context():
         auth.store_token(user_id, 'nonexpired-main', future, None)
         auth.store_token(user_id, 'nonexpired-sub', future, subclient)
         token3 = auth.store_token(user_id, 'expired-sub', past, subclient)
 
+        # We should not find the given tokens as unhashed tokens.
+        tokens_coll = self.app.db('tokens')
+        self.assertIsNone(tokens_coll.find_one({'token': 'nonespired-main'}))
+        self.assertIsNone(tokens_coll.find_one({'token': 'nonespired-sub'}))
+        self.assertIsNone(tokens_coll.find_one({'token': 'expired-sub'}))
+
         with self.app.test_request_context(
                 headers={'Authorization': self.make_header('nonexpired-main')}):
             self.assertTrue(auth.validate_token())
@@ -172,19 +179,19 @@ class AuthenticationTests(AbstractPillarTest):
         with self.app.test_request_context():
             from pillar.api.utils import authentication as auth
 
-            auth.store_token(user_id, 'long-expired',
+            tokdat_le = auth.store_token(user_id, 'long-expired',
                                          now - datetime.timedelta(days=365), None)
-            auth.store_token(user_id, 'short-expired',
+            tokdat_se = auth.store_token(user_id, 'short-expired',
                                          now - datetime.timedelta(seconds=5), None)
-            auth.store_token(user_id, 'not-expired',
+            tokdat_ne = auth.store_token(user_id, 'not-expired',
                                          now + datetime.timedelta(days=1), None)
 
             # Validation should clean up old tokens.
             auth.validate_this_token('je', 'moeder')
 
             token_coll = self.app.data.driver.db['tokens']
-            self.assertEqual({'short-expired', 'not-expired'},
+            self.assertEqual({tokdat_se['token_hashed'], tokdat_ne['token_hashed']},
-                             {item['token'] for item in token_coll.find()})
+                             {item['token_hashed'] for item in token_coll.find()})
 
 
 class UserListTests(AbstractPillarTest):
@@ -703,7 +710,6 @@ class UserCreationTest(AbstractPillarTest):
 
 
 class CurrentUserTest(AbstractPillarTest):
-
     def test_current_user_logged_in(self):
         self.enter_app_context()
 

tests/test_api/test_blender_id_subclient.py

@@ -42,6 +42,8 @@ class BlenderIdSubclientTest(AbstractPillarTest):
 
     @responses.activate
     def test_store_multiple_tokens(self):
+        from pillar.api.utils.authentication import hash_auth_token
+
         scst1 = '%s-1' % TEST_SUBCLIENT_TOKEN
         scst2 = '%s-2' % TEST_SUBCLIENT_TOKEN
         db_user1 = self._common_user_test(201, scst=scst1)
@@ -51,8 +53,10 @@ class BlenderIdSubclientTest(AbstractPillarTest):
         # Now there should be two tokens.
         with self.app.test_request_context():
             tokens = self.app.data.driver.db['tokens']
-            self.assertIsNotNone(tokens.find_one({'user': db_user1['_id'], 'token': scst1}))
+            self.assertIsNotNone(tokens.find_one(
-            self.assertIsNotNone(tokens.find_one({'user': db_user1['_id'], 'token': scst2}))
+                {'user': db_user1['_id'], 'token_hashed': hash_auth_token(scst1)}))
+            self.assertIsNotNone(tokens.find_one(
+                {'user': db_user1['_id'], 'token_hashed': hash_auth_token(scst2)}))
 
         # There should still be only one auth element for blender-id in the user doc.
         self.assertEqual(1, len(db_user1['auth']))
@@ -76,6 +80,8 @@ class BlenderIdSubclientTest(AbstractPillarTest):
     def _common_user_test(self, expected_status_code, scst=TEST_SUBCLIENT_TOKEN,
                           expected_full_name=TEST_FULL_NAME,
                           mock_happy_blender_id=True):
+        from pillar.api.utils.authentication import hash_auth_token
+
         if mock_happy_blender_id:
             self.mock_blenderid_validate_happy()
 
@@ -104,7 +110,7 @@ class BlenderIdSubclientTest(AbstractPillarTest):
             # Check that the token was succesfully stored.
             tokens = self.app.data.driver.db['tokens']
             db_token = tokens.find_one({'user': db_user['_id'],
-                                        'token': scst})
+                                        'token_hashed': hash_auth_token(scst)})
             self.assertIsNotNone(db_token)
 
         return db_user

tests/test_api/test_local_auth.py

@@ -38,6 +38,8 @@ class LocalAuthTest(AbstractPillarTest):
         self.assertEqual(200, resp.status_code, resp.data)
 
     def test_login_expired_token(self):
+        from pillar.api.utils.authentication import hash_auth_token
+
         user_id = self.create_test_user()
 
         resp = self.client.post('/api/auth/make-token',
@@ -52,7 +54,7 @@ class LocalAuthTest(AbstractPillarTest):
             tokens = self.app.data.driver.db['tokens']
 
             exp = datetime.datetime.now(tz=tz_util.utc) - datetime.timedelta(1)
-            result = tokens.update_one({'token': token},
+            result = tokens.update_one({'token_hashed': hash_auth_token(token)},
                                        {'$set': {'expire_time': exp}})
             self.assertEqual(1, result.modified_count)