Merge pull request #5027 from matrix-org/babolivier/account_expiration

Add time-based account expiration

synapse/api/auth.py

@@ -64,6 +64,8 @@ class Auth(object):
         self.token_cache = LruCache(CACHE_SIZE_FACTOR * 10000)
         register_cache("cache", "token_cache", self.token_cache)
 
+        self._account_validity = hs.config.account_validity
+
     @defer.inlineCallbacks
     def check_from_context(self, room_version, event, context, do_sig_check=True):
         prev_state_ids = yield context.get_prev_state_ids(self.store)
@@ -226,6 +228,16 @@ class Auth(object):
             token_id = user_info["token_id"]
             is_guest = user_info["is_guest"]
 
+            # Deny the request if the user account has expired.
+            if self._account_validity.enabled:
+                expiration_ts = yield self.store.get_expiration_ts_for_user(user)
+                if self.clock.time_msec() >= expiration_ts:
+                    raise AuthError(
+                        403,
+                        "User account has expired",
+                        errcode=Codes.EXPIRED_ACCOUNT,
+                    )
+
             # device_id may not be present if get_user_by_access_token has been
             # stubbed out.
             device_id = user_info.get("device_id")

synapse/api/errors.py

@@ -60,6 +60,7 @@ class Codes(object):
     UNSUPPORTED_ROOM_VERSION = "M_UNSUPPORTED_ROOM_VERSION"
     INCOMPATIBLE_ROOM_VERSION = "M_INCOMPATIBLE_ROOM_VERSION"
     WRONG_ROOM_KEYS_VERSION = "M_WRONG_ROOM_KEYS_VERSION"
+    EXPIRED_ACCOUNT = "ORG_MATRIX_EXPIRED_ACCOUNT"
 
 
 class CodeMessageException(RuntimeError):

synapse/config/registration.py

@@ -20,6 +20,15 @@ from synapse.types import RoomAlias
 from synapse.util.stringutils import random_string_with_symbols
 
 
+class AccountValidityConfig(Config):
+    def __init__(self, config):
+        self.enabled = (len(config) > 0)
+
+        period = config.get("period", None)
+        if period:
+            self.period = self.parse_duration(period)
+
+
 class RegistrationConfig(Config):
 
     def read_config(self, config):
@@ -31,6 +40,8 @@ class RegistrationConfig(Config):
                 strtobool(str(config["disable_registration"]))
             )
 
+        self.account_validity = AccountValidityConfig(config.get("account_validity", {}))
+
         self.registrations_require_3pid = config.get("registrations_require_3pid", [])
         self.allowed_local_3pids = config.get("allowed_local_3pids", [])
         self.enable_3pid_lookup = config.get("enable_3pid_lookup", True)
@@ -76,6 +87,12 @@ class RegistrationConfig(Config):
         #
         #enable_registration: false
 
+        # Optional account validity parameter. This allows for, e.g., accounts to
+        # be denied any request after a given period.
+        #
+        #account_validity:
+        #  period: 6w
+
         # The user must provide all of the below types of 3PID when registering.
         #
         #registrations_require_3pid:

synapse/storage/registration.py

@@ -86,6 +86,26 @@ class RegistrationWorkerStore(SQLBaseStore):
             "get_user_by_access_token", self._query_for_auth, token
         )
 
+    @cachedInlineCallbacks()
+    def get_expiration_ts_for_user(self, user):
+        """Get the expiration timestamp for the account bearing a given user ID.
+
+        Args:
+            user (str): The ID of the user.
+        Returns:
+            defer.Deferred: None, if the account has no expiration timestamp,
+            otherwise int representation of the timestamp (as a number of
+            milliseconds since epoch).
+        """
+        res = yield self._simple_select_one_onecol(
+            table="account_validity",
+            keyvalues={"user_id": user.to_string()},
+            retcol="expiration_ts_ms",
+            allow_none=True,
+            desc="get_expiration_date_for_user",
+        )
+        defer.returnValue(res)
+
     @defer.inlineCallbacks
     def is_server_admin(self, user):
         res = yield self._simple_select_one_onecol(
@@ -425,6 +445,8 @@ class RegistrationStore(
             columns=["creation_ts"],
         )
 
+        self._account_validity = hs.config.account_validity
+
         # we no longer use refresh tokens, but it's possible that some people
         # might have a background update queued to build this index. Just
         # clear the background update.
@@ -561,6 +583,18 @@ class RegistrationStore(
                         "user_type": user_type,
                     },
                 )
+
+            if self._account_validity.enabled:
+                now_ms = self.clock.time_msec()
+                expiration_ts = now_ms + self._account_validity.period
+                self._simple_insert_txn(
+                    txn,
+                    "account_validity",
+                    values={
+                        "user_id": user_id,
+                        "expiration_ts_ms": expiration_ts,
+                    }
+                )
         except self.database_engine.module.IntegrityError:
             raise StoreError(400, "User ID already taken.", errcode=Codes.USER_IN_USE)
 

synapse/storage/schema/delta/54/account_validity.sql

@@ -0,0 +1,20 @@
+/* Copyright 2019 New Vector Ltd
+ *
+ * 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.
+ */
+
+-- Track what users are in public rooms.
+CREATE TABLE IF NOT EXISTS account_validity (
+    user_id TEXT PRIMARY KEY,
+    expiration_ts_ms BIGINT NOT NULL
+);