Add rate-limiting on registration (#4735)

* Rate-limiting for registration

* Add unit test for registration rate limiting

* Add config parameters for rate limiting on auth endpoints

* Doc

* Fix doc of rate limiting function

Co-Authored-By: babolivier <contact@brendanabolivier.com>

* Incorporate review

* Fix config parsing

* Fix linting errors

* Set default config for auth rate limiting

* Fix tests

* Add changelog

* Advance reactor instead of mocked clock

* Move parameters to registration specific config and give them more sensible default values

* Remove unused config options

* Don't mock the rate limiter un MAU tests

* Rename _register_with_store into register_with_store

* Make CI happy

* Remove unused import

* Update sample config

* Fix ratelimiting test for py2

* Add non-guest test

1 files changed, 18 insertions, 0 deletions

diff --git a/synapse/config/registration.py b/synapse/config/registration.py

index 2881482f96..d32f6fff73 100644
--- a/synapse/config/registration.py
+++ b/synapse/config/registration.py
@@ -54,6 +54,13 @@ class RegistrationConfig(Config):
             config.get("disable_msisdn_registration", False)
         )
 
+        self.rc_registration_requests_per_second = config.get(
+            "rc_registration_requests_per_second", 0.17,
+        )
+        self.rc_registration_request_burst_count = config.get(
+            "rc_registration_request_burst_count", 3,
+        )
+
     def default_config(self, generate_secrets=False, **kwargs):
         if generate_secrets:
             registration_shared_secret = 'registration_shared_secret: "%s"' % (
@@ -140,6 +147,17 @@ class RegistrationConfig(Config):
         # users cannot be auto-joined since they do not exist.
         #
         autocreate_auto_join_rooms: true
+
+        # Number of registration requests a client can send per second.
+        # Defaults to 1/minute (0.17).
+        #
+        #rc_registration_requests_per_second: 0.17
+
+        # Number of registration requests a client can send before being
+        # throttled.
+        # Defaults to 3.
+        #
+        #rc_registration_request_burst_count: 3.0
         """ % locals()
 
     def add_arguments(self, parser):