Merge pull request #3630 from matrix-org/neilj/mau_sign_in_log_in_limits

Initial impl of capping MAU

2 files changed, 35 insertions, 3 deletions

diff --git a/synapse/handlers/auth.py b/synapse/handlers/auth.py
index 5d03bfa5f7..184eef09d0 100644
--- a/synapse/handlers/auth.py
+++ b/synapse/handlers/auth.py
@@ -520,6 +520,7 @@ 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)
+        yield 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
@@ -731,15 +732,18 @@ class AuthHandler(BaseHandler):
                                                   device_id)
         defer.returnValue(access_token)
 
+    @defer.inlineCallbacks
     def validate_short_term_login_token_and_get_user_id(self, login_token):
+        yield self._check_mau_limits()
         auth_api = self.hs.get_auth()
+        user_id = None
         try:
             macaroon = pymacaroons.Macaroon.deserialize(login_token)
             user_id = auth_api.get_user_id_from_macaroon(macaroon)
             auth_api.validate_macaroon(macaroon, "login", True, user_id)
-            return user_id
         except Exception:
             raise AuthError(403, "Invalid token", errcode=Codes.FORBIDDEN)
+        defer.returnValue(user_id)
 
     @defer.inlineCallbacks
     def delete_access_token(self, access_token):
@@ -903,6 +907,19 @@ class AuthHandler(BaseHandler):
         else:
             return defer.succeed(False)
 
+    @defer.inlineCallbacks
+    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 = yield 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 234f8e8019..289704b241 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.
         """
+        yield 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 '=_-./'",
             )
+        yield 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")
-
+        yield self._check_mau_limits()
         need_register = True
 
         try:
@@ -531,3 +533,16 @@ class RegistrationHandler(BaseHandler):
             remote_room_hosts=remote_room_hosts,
             action="join",
         )
+
+    @defer.inlineCallbacks
+    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 = yield self.store.count_monthly_users()
+            if current_mau >= self.hs.config.max_mau_value:
+                raise RegistrationError(
+                    403, "MAU Limit Exceeded", Codes.MAU_LIMIT_EXCEEDED
+                )