Add account expiration feature

10 files changed, 144 insertions, 4 deletions

diff --git a/changelog.d/5027.feature b/changelog.d/5027.feature
new file mode 100644
index 0000000000..12766a82a7
--- /dev/null
+++ b/changelog.d/5027.feature
@@ -0,0 +1 @@
+Add time-based account expiration.
diff --git a/docs/sample_config.yaml b/docs/sample_config.yaml
index 4ada0fba0e..5594c8b9af 100644
--- a/docs/sample_config.yaml
+++ b/docs/sample_config.yaml
@@ -643,6 +643,12 @@ uploads_path: "DATADIR/uploads"
 #
 #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:
diff --git a/synapse/api/auth.py b/synapse/api/auth.py
index e8112d5f05..976e0dd18b 100644
--- a/synapse/api/auth.py
+++ b/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")
diff --git a/synapse/api/errors.py b/synapse/api/errors.py
index 0b464834ce..4c33450e7f 100644
--- a/synapse/api/errors.py
+++ b/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):
diff --git a/synapse/config/registration.py b/synapse/config/registration.py
index f6b2b9ceee..b7a7b4f1cf 100644
--- a/synapse/config/registration.py
+++ b/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.registration_shared_secret = config.get("registration_shared_secret")
@@ -75,6 +86,12 @@ 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:
diff --git a/synapse/storage/prepare_database.py b/synapse/storage/prepare_database.py
index fa36daac52..e042221774 100644
--- a/synapse/storage/prepare_database.py
+++ b/synapse/storage/prepare_database.py
@@ -25,7 +25,7 @@ logger = logging.getLogger(__name__)
 
 # Remember to update this number every time a change is made to database
 # schema files, so the users will be informed on server restarts.
-SCHEMA_VERSION = 53
+SCHEMA_VERSION = 54
 
 dir_path = os.path.abspath(os.path.dirname(__file__))
 
diff --git a/synapse/storage/registration.py b/synapse/storage/registration.py
index 9b6c28892c..eede8ae4d2 100644
--- a/synapse/storage/registration.py
+++ b/synapse/storage/registration.py
@@ -86,6 +86,26 @@ class RegistrationWorkerStore(SQLBaseStore):
             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(
@@ -351,6 +371,8 @@ class RegistrationStore(RegistrationWorkerStore,
             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.
@@ -485,6 +507,18 @@ class RegistrationStore(RegistrationWorkerStore,
                         "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
diff --git a/synapse/storage/schema/delta/54/account_validity.sql b/synapse/storage/schema/delta/54/account_validity.sql
new file mode 100644
index 0000000000..57249262d7
--- /dev/null
+++ b/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
+);
diff --git a/tests/rest/client/v2_alpha/test_register.py b/tests/rest/client/v2_alpha/test_register.py
index a45e6e5e1f..d3611ed21f 100644
--- a/tests/rest/client/v2_alpha/test_register.py
+++ b/tests/rest/client/v2_alpha/test_register.py
@@ -1,15 +1,18 @@
+import datetime
 import json
 
 from synapse.api.constants import LoginType
+from synapse.api.errors import Codes
 from synapse.appservice import ApplicationService
-from synapse.rest.client.v2_alpha.register import register_servlets
+from synapse.rest.client.v1 import admin, login
+from synapse.rest.client.v2_alpha import register, sync
 
 from tests import unittest
 
 
 class RegisterRestServletTestCase(unittest.HomeserverTestCase):
 
-    servlets = [register_servlets]
+    servlets = [register.register_servlets]
 
     def make_homeserver(self, reactor, clock):
 
@@ -181,3 +184,47 @@ class RegisterRestServletTestCase(unittest.HomeserverTestCase):
         self.render(request)
 
         self.assertEquals(channel.result["code"], b"200", channel.result)
+
+
+class AccountValidityTestCase(unittest.HomeserverTestCase):
+
+    servlets = [
+        register.register_servlets,
+        admin.register_servlets,
+        login.register_servlets,
+        sync.register_servlets,
+    ]
+
+    def make_homeserver(self, reactor, clock):
+        config = self.default_config()
+        config.enable_registration = True
+        config.account_validity.enabled = True
+        config.account_validity.period = 604800000  # Time in ms for 1 week
+        self.hs = self.setup_test_homeserver(config=config)
+
+        return self.hs
+
+    def test_validity_period(self):
+        self.register_user("kermit", "monkey")
+        tok = self.login("kermit", "monkey")
+
+        # The specific endpoint doesn't matter, all we need is an authenticated
+        # endpoint.
+        request, channel = self.make_request(
+            b"GET", "/sync", access_token=tok,
+        )
+        self.render(request)
+
+        self.assertEquals(channel.result["code"], b"200", channel.result)
+
+        self.reactor.advance(datetime.timedelta(weeks=1).total_seconds())
+
+        request, channel = self.make_request(
+            b"GET", "/sync", access_token=tok,
+        )
+        self.render(request)
+
+        self.assertEquals(channel.result["code"], b"403", channel.result)
+        self.assertEquals(
+            channel.json_body["errcode"], Codes.EXPIRED_ACCOUNT, channel.result,
+        )
diff --git a/tests/test_state.py b/tests/test_state.py
index e20c33322a..ce2b7eb7ed 100644
--- a/tests/test_state.py
+++ b/tests/test_state.py
@@ -24,7 +24,7 @@ from synapse.state import StateHandler, StateResolutionHandler
 
 from tests import unittest
 
-from .utils import MockClock
+from .utils import MockClock, default_config
 
 _next_event_id = 1000
 
@@ -159,6 +159,7 @@ class StateTestCase(unittest.TestCase):
         self.store = StateGroupStore()
         hs = Mock(
             spec_set=[
+                "config",
                 "get_datastore",
                 "get_auth",
                 "get_state_handler",
@@ -166,6 +167,7 @@ class StateTestCase(unittest.TestCase):
                 "get_state_resolution_handler",
             ]
         )
+        hs.config = default_config("tesths")
         hs.get_datastore.return_value = self.store
         hs.get_state_handler.return_value = None
         hs.get_clock.return_value = MockClock()