limit register and sign in on number of monthly users

5 files changed, 69 insertions, 2 deletions

diff --git a/synapse/api/errors.py b/synapse/api/errors.py
index 6074df292f..14f5540280 100644
--- a/synapse/api/errors.py
+++ b/synapse/api/errors.py
@@ -55,6 +55,7 @@ class Codes(object):
     SERVER_NOT_TRUSTED = "M_SERVER_NOT_TRUSTED"
     CONSENT_NOT_GIVEN = "M_CONSENT_NOT_GIVEN"
     CANNOT_LEAVE_SERVER_NOTICE_ROOM = "M_CANNOT_LEAVE_SERVER_NOTICE_ROOM"
+    MAU_LIMIT_EXCEEDED = "M_MAU_LIMIT_EXCEEDED"
 
 
 class CodeMessageException(RuntimeError):
diff --git a/synapse/config/server.py b/synapse/config/server.py
index 18102656b0..8b335bff3f 100644
--- a/synapse/config/server.py
+++ b/synapse/config/server.py
@@ -67,6 +67,11 @@ class ServerConfig(Config):
             "block_non_admin_invites", False,
         )
 
+        # Options to control access by tracking MAU
+        self.limit_usage_by_mau = config.get("limit_usage_by_mau", False)
+        self.max_mau_value = config.get(
+                "max_mau_value", 0,
+        )
         # FIXME: federation_domain_whitelist needs sytests
         self.federation_domain_whitelist = None
         federation_domain_whitelist = config.get(
diff --git a/synapse/handlers/auth.py b/synapse/handlers/auth.py
index 402e44cdef..f3734f11bd 100644
--- a/synapse/handlers/auth.py
+++ b/synapse/handlers/auth.py
@@ -519,6 +519,7 @@ class AuthHandler(BaseHandler):
         """
         logger.info("Logging in user %s on device %s", user_id, device_id)
         access_token = yield self.issue_access_token(user_id, device_id)
+        self._check_mau_limits()
 
         # the device *should* have been registered before we got here; however,
         # it's possible we raced against a DELETE operation. The thing we
@@ -729,6 +730,7 @@ class AuthHandler(BaseHandler):
         defer.returnValue(access_token)
 
     def validate_short_term_login_token_and_get_user_id(self, login_token):
+        self._check_mau_limits()
         auth_api = self.hs.get_auth()
         try:
             macaroon = pymacaroons.Macaroon.deserialize(login_token)
@@ -892,6 +894,17 @@ class AuthHandler(BaseHandler):
         else:
             return defer.succeed(False)
 
+    def _check_mau_limits(self):
+        """
+        Ensure that if mau blocking is enabled that invalid users cannot
+        log in.
+        """
+        if self.hs.config.limit_usage_by_mau is True:
+            current_mau = self.store.count_monthly_users()
+            if current_mau >= self.hs.config.max_mau_value:
+                raise AuthError(
+                        403, "MAU Limit Exceeded", errcode=Codes.MAU_LIMIT_EXCEEDED
+                )
 
 @attr.s
 class MacaroonGenerator(object):
diff --git a/synapse/handlers/register.py b/synapse/handlers/register.py
index 7caff0cbc8..f46b8355c0 100644
--- a/synapse/handlers/register.py
+++ b/synapse/handlers/register.py
@@ -45,7 +45,7 @@ class RegistrationHandler(BaseHandler):
             hs (synapse.server.HomeServer):
         """
         super(RegistrationHandler, self).__init__(hs)
-
+        self.hs = hs
         self.auth = hs.get_auth()
         self._auth_handler = hs.get_auth_handler()
         self.profile_handler = hs.get_profile_handler()
@@ -144,6 +144,7 @@ class RegistrationHandler(BaseHandler):
         Raises:
             RegistrationError if there was a problem registering.
         """
+        self._check_mau_limits()
         password_hash = None
         if password:
             password_hash = yield self.auth_handler().hash(password)
@@ -288,6 +289,7 @@ class RegistrationHandler(BaseHandler):
                 400,
                 "User ID can only contain characters a-z, 0-9, or '=_-./'",
             )
+        self._check_mau_limits()
         user = UserID(localpart, self.hs.hostname)
         user_id = user.to_string()
 
@@ -437,7 +439,7 @@ class RegistrationHandler(BaseHandler):
         """
         if localpart is None:
             raise SynapseError(400, "Request must include user id")
-
+        self._check_mau_limits()
         need_register = True
 
         try:
@@ -531,3 +533,15 @@ class RegistrationHandler(BaseHandler):
             remote_room_hosts=remote_room_hosts,
             action="join",
         )
+
+    def _check_mau_limits(self):
+        """
+        Do not accept registrations if monthly active user limits exceeded
+         and limiting is enabled
+        """
+        if self.hs.config.limit_usage_by_mau is True:
+            current_mau = self.store.count_monthly_users()
+            if current_mau >= self.hs.config.max_mau_value:
+                raise RegistrationError(
+                    403, "MAU Limit Exceeded", Codes.MAU_LIMIT_EXCEEDED
+                )
diff --git a/synapse/storage/__init__.py b/synapse/storage/__init__.py
index ba88a54979..6a75bf0e52 100644
--- a/synapse/storage/__init__.py
+++ b/synapse/storage/__init__.py
@@ -19,6 +19,7 @@ import logging
 import time
 
 from dateutil import tz
+from prometheus_client import Gauge
 
 from synapse.api.constants import PresenceState
 from synapse.storage.devices import DeviceStore
@@ -60,6 +61,13 @@ from .util.id_generators import ChainedIdGenerator, IdGenerator, StreamIdGenerat
 
 logger = logging.getLogger(__name__)
 
+# Gauges to expose monthly active user control metrics
+current_mau_gauge = Gauge("synapse_admin_current_mau", "Current MAU")
+max_mau_value_gauge = Gauge("synapse_admin_max_mau_value", "MAU Limit")
+limit_usage_by_mau_gauge = Gauge(
+    "synapse_admin_limit_usage_by_mau", "MAU Limiting enabled"
+)
+
 
 class DataStore(RoomMemberStore, RoomStore,
                 RegistrationStore, StreamStore, ProfileStore,
@@ -266,6 +274,32 @@ class DataStore(RoomMemberStore, RoomStore,
 
         return self.runInteraction("count_users", _count_users)
 
+    def count_monthly_users(self):
+        """
+        Counts the number of users who used this homeserver in the last 30 days
+        This method should be refactored with count_daily_users - the only
+        reason not to is waiting on definition of mau
+        returns:
+            int: count of current monthly active users
+        """
+        def _count_monthly_users(txn):
+            thirty_days_ago = int(self._clock.time_msec()) - (1000 * 60 * 60 * 24 * 30)
+            sql = """
+                SELECT COUNT(*) FROM user_ips
+                WHERE last_seen > ?
+            """
+            txn.execute(sql, (thirty_days_ago,))
+            count, = txn.fetchone()
+
+            self._current_mau = count
+            current_mau_gauge.set(self._current_mau)
+            max_mau_value_gauge.set(self.hs.config.max_mau_value)
+            limit_usage_by_mau_gauge.set(self.hs.config.limit_usage_by_mau)
+            logger.info("calling mau stats")
+            return count
+        return self.runInteraction("count_monthly_users", _count_monthly_users)
+
+
     def count_r30_users(self):
         """
         Counts the number of 30 day retained users, defined as:-