Make all the rate limiting options more consistent (#5181)

8 files changed, 138 insertions, 131 deletions

diff --git a/changelog.d/5181.feature b/changelog.d/5181.feature
new file mode 100644
index 0000000000..5ce13aa2ea
--- /dev/null
+++ b/changelog.d/5181.feature
@@ -0,0 +1 @@
+Ratelimiting configuration for clients sending messages and the federation server has been altered to match login ratelimiting. The old configuration names will continue working. Check the sample config for details of the new names.
diff --git a/docs/sample_config.yaml b/docs/sample_config.yaml
index c4e5c4cf39..09ee0e8984 100644
--- a/docs/sample_config.yaml
+++ b/docs/sample_config.yaml
@@ -446,21 +446,15 @@ log_config: "CONFDIR/SERVERNAME.log.config"
 
 ## Ratelimiting ##
 
-# Number of messages a client can send per second
-#
-#rc_messages_per_second: 0.2
-
-# Number of message a client can send before being throttled
-#
-#rc_message_burst_count: 10.0
-
-# Ratelimiting settings for registration and login.
+# Ratelimiting settings for client actions (registration, login, messaging).
 #
 # Each ratelimiting configuration is made of two parameters:
 #   - per_second: number of requests a client can send per second.
 #   - burst_count: number of requests a client can send before being throttled.
 #
 # Synapse currently uses the following configurations:
+#   - one for messages that ratelimits sending based on the account the client
+#     is using
 #   - one for registration that ratelimits registration requests based on the
 #     client's IP address.
 #   - one for login that ratelimits login requests based on the client's IP
@@ -473,6 +467,10 @@ log_config: "CONFDIR/SERVERNAME.log.config"
 #
 # The defaults are as shown below.
 #
+#rc_message:
+#  per_second: 0.2
+#  burst_count: 10
+#
 #rc_registration:
 #  per_second: 0.17
 #  burst_count: 3
@@ -488,29 +486,28 @@ log_config: "CONFDIR/SERVERNAME.log.config"
 #    per_second: 0.17
 #    burst_count: 3
 
-# The federation window size in milliseconds
-#
-#federation_rc_window_size: 1000
 
-# The number of federation requests from a single server in a window
-# before the server will delay processing the request.
+# Ratelimiting settings for incoming federation
 #
-#federation_rc_sleep_limit: 10
-
-# The duration in milliseconds to delay processing events from
-# remote servers by if they go over the sleep limit.
-#
-#federation_rc_sleep_delay: 500
-
-# The maximum number of concurrent federation requests allowed
-# from a single server
+# The rc_federation configuration is made up of the following settings:
+#   - window_size: window size in milliseconds
+#   - sleep_limit: number of federation requests from a single server in
+#     a window before the server will delay processing the request.
+#   - sleep_delay: duration in milliseconds to delay processing events
+#     from remote servers by if they go over the sleep limit.
+#   - reject_limit: maximum number of concurrent federation requests
+#     allowed from a single server
+#   - concurrent: number of federation requests to concurrently process
+#     from a single server
 #
-#federation_rc_reject_limit: 50
-
-# The number of federation requests to concurrently process from a
-# single server
+# The defaults are as shown below.
 #
-#federation_rc_concurrent: 3
+#rc_federation:
+#  window_size: 1000
+#  sleep_limit: 10
+#  sleep_delay: 500
+#  reject_limit: 50
+#  concurrent: 3
 
 # Target outgoing federation transaction frequency for sending read-receipts,
 # per-room.
diff --git a/synapse/config/ratelimiting.py b/synapse/config/ratelimiting.py
index 5a68399e63..5a9adac480 100644
--- a/synapse/config/ratelimiting.py
+++ b/synapse/config/ratelimiting.py
@@ -16,16 +16,56 @@ from ._base import Config
 
 
 class RateLimitConfig(object):
-    def __init__(self, config):
-        self.per_second = config.get("per_second", 0.17)
-        self.burst_count = config.get("burst_count", 3.0)
+    def __init__(self, config, defaults={"per_second": 0.17, "burst_count": 3.0}):
+        self.per_second = config.get("per_second", defaults["per_second"])
+        self.burst_count = config.get("burst_count", defaults["burst_count"])
 
 
-class RatelimitConfig(Config):
+class FederationRateLimitConfig(object):
+    _items_and_default = {
+        "window_size": 10000,
+        "sleep_limit": 10,
+        "sleep_delay": 500,
+        "reject_limit": 50,
+        "concurrent": 3,
+    }
+
+    def __init__(self, **kwargs):
+        for i in self._items_and_default.keys():
+            setattr(self, i, kwargs.get(i) or self._items_and_default[i])
+
 
+class RatelimitConfig(Config):
     def read_config(self, config):
-        self.rc_messages_per_second = config.get("rc_messages_per_second", 0.2)
-        self.rc_message_burst_count = config.get("rc_message_burst_count", 10.0)
+
+        # Load the new-style messages config if it exists. Otherwise fall back
+        # to the old method.
+        if "rc_message" in config:
+            self.rc_message = RateLimitConfig(
+                config["rc_message"], defaults={"per_second": 0.2, "burst_count": 10.0}
+            )
+        else:
+            self.rc_message = RateLimitConfig(
+                {
+                    "per_second": config.get("rc_messages_per_second", 0.2),
+                    "burst_count": config.get("rc_message_burst_count", 10.0),
+                }
+            )
+
+        # Load the new-style federation config, if it exists. Otherwise, fall
+        # back to the old method.
+        if "federation_rc" in config:
+            self.rc_federation = FederationRateLimitConfig(**config["rc_federation"])
+        else:
+            self.rc_federation = FederationRateLimitConfig(
+                **{
+                    "window_size": config.get("federation_rc_window_size"),
+                    "sleep_limit": config.get("federation_rc_sleep_limit"),
+                    "sleep_delay": config.get("federation_rc_sleep_delay"),
+                    "reject_limit": config.get("federation_rc_reject_limit"),
+                    "concurrent": config.get("federation_rc_concurrent"),
+                }
+            )
 
         self.rc_registration = RateLimitConfig(config.get("rc_registration", {}))
 
@@ -33,38 +73,26 @@ class RatelimitConfig(Config):
         self.rc_login_address = RateLimitConfig(rc_login_config.get("address", {}))
         self.rc_login_account = RateLimitConfig(rc_login_config.get("account", {}))
         self.rc_login_failed_attempts = RateLimitConfig(
-            rc_login_config.get("failed_attempts", {}),
+            rc_login_config.get("failed_attempts", {})
         )
 
-        self.federation_rc_window_size = config.get("federation_rc_window_size", 1000)
-        self.federation_rc_sleep_limit = config.get("federation_rc_sleep_limit", 10)
-        self.federation_rc_sleep_delay = config.get("federation_rc_sleep_delay", 500)
-        self.federation_rc_reject_limit = config.get("federation_rc_reject_limit", 50)
-        self.federation_rc_concurrent = config.get("federation_rc_concurrent", 3)
-
         self.federation_rr_transactions_per_room_per_second = config.get(
-            "federation_rr_transactions_per_room_per_second", 50,
+            "federation_rr_transactions_per_room_per_second", 50
         )
 
     def default_config(self, **kwargs):
         return """\
         ## Ratelimiting ##
 
-        # Number of messages a client can send per second
-        #
-        #rc_messages_per_second: 0.2
-
-        # Number of message a client can send before being throttled
-        #
-        #rc_message_burst_count: 10.0
-
-        # Ratelimiting settings for registration and login.
+        # Ratelimiting settings for client actions (registration, login, messaging).
         #
         # Each ratelimiting configuration is made of two parameters:
         #   - per_second: number of requests a client can send per second.
         #   - burst_count: number of requests a client can send before being throttled.
         #
         # Synapse currently uses the following configurations:
+        #   - one for messages that ratelimits sending based on the account the client
+        #     is using
         #   - one for registration that ratelimits registration requests based on the
         #     client's IP address.
         #   - one for login that ratelimits login requests based on the client's IP
@@ -77,6 +105,10 @@ class RatelimitConfig(Config):
         #
         # The defaults are as shown below.
         #
+        #rc_message:
+        #  per_second: 0.2
+        #  burst_count: 10
+        #
         #rc_registration:
         #  per_second: 0.17
         #  burst_count: 3
@@ -92,29 +124,28 @@ class RatelimitConfig(Config):
         #    per_second: 0.17
         #    burst_count: 3
 
-        # The federation window size in milliseconds
-        #
-        #federation_rc_window_size: 1000
-
-        # The number of federation requests from a single server in a window
-        # before the server will delay processing the request.
-        #
-        #federation_rc_sleep_limit: 10
 
-        # The duration in milliseconds to delay processing events from
-        # remote servers by if they go over the sleep limit.
+        # Ratelimiting settings for incoming federation
         #
-        #federation_rc_sleep_delay: 500
-
-        # The maximum number of concurrent federation requests allowed
-        # from a single server
+        # The rc_federation configuration is made up of the following settings:
+        #   - window_size: window size in milliseconds
+        #   - sleep_limit: number of federation requests from a single server in
+        #     a window before the server will delay processing the request.
+        #   - sleep_delay: duration in milliseconds to delay processing events
+        #     from remote servers by if they go over the sleep limit.
+        #   - reject_limit: maximum number of concurrent federation requests
+        #     allowed from a single server
+        #   - concurrent: number of federation requests to concurrently process
+        #     from a single server
         #
-        #federation_rc_reject_limit: 50
-
-        # The number of federation requests to concurrently process from a
-        # single server
+        # The defaults are as shown below.
         #
-        #federation_rc_concurrent: 3
+        #rc_federation:
+        #  window_size: 1000
+        #  sleep_limit: 10
+        #  sleep_delay: 500
+        #  reject_limit: 50
+        #  concurrent: 3
 
         # Target outgoing federation transaction frequency for sending read-receipts,
         # per-room.
diff --git a/synapse/federation/transport/server.py b/synapse/federation/transport/server.py
index 9030eb18c5..385eda2dca 100644
--- a/synapse/federation/transport/server.py
+++ b/synapse/federation/transport/server.py
@@ -63,11 +63,7 @@ class TransportLayerServer(JsonResource):
         self.authenticator = Authenticator(hs)
         self.ratelimiter = FederationRateLimiter(
             self.clock,
-            window_size=hs.config.federation_rc_window_size,
-            sleep_limit=hs.config.federation_rc_sleep_limit,
-            sleep_msec=hs.config.federation_rc_sleep_delay,
-            reject_limit=hs.config.federation_rc_reject_limit,
-            concurrent_requests=hs.config.federation_rc_concurrent,
+            config=hs.config.rc_federation,
         )
 
         self.register_servlets()
diff --git a/synapse/handlers/_base.py b/synapse/handlers/_base.py
index ac09d03ba9..dca337ec61 100644
--- a/synapse/handlers/_base.py
+++ b/synapse/handlers/_base.py
@@ -90,8 +90,8 @@ class BaseHandler(object):
             messages_per_second = override.messages_per_second
             burst_count = override.burst_count
         else:
-            messages_per_second = self.hs.config.rc_messages_per_second
-            burst_count = self.hs.config.rc_message_burst_count
+            messages_per_second = self.hs.config.rc_message.per_second
+            burst_count = self.hs.config.rc_message.burst_count
 
         allowed, time_allowed = self.ratelimiter.can_do_action(
             user_id, time_now,
diff --git a/synapse/rest/client/v2_alpha/register.py b/synapse/rest/client/v2_alpha/register.py
index dc3e265bcd..3d045880b9 100644
--- a/synapse/rest/client/v2_alpha/register.py
+++ b/synapse/rest/client/v2_alpha/register.py
@@ -31,6 +31,7 @@ from synapse.api.errors import (
     SynapseError,
     UnrecognizedRequestError,
 )
+from synapse.config.ratelimiting import FederationRateLimitConfig
 from synapse.config.server import is_threepid_reserved
 from synapse.http.servlet import (
     RestServlet,
@@ -153,16 +154,18 @@ class UsernameAvailabilityRestServlet(RestServlet):
         self.registration_handler = hs.get_registration_handler()
         self.ratelimiter = FederationRateLimiter(
             hs.get_clock(),
-            # Time window of 2s
-            window_size=2000,
-            # Artificially delay requests if rate > sleep_limit/window_size
-            sleep_limit=1,
-            # Amount of artificial delay to apply
-            sleep_msec=1000,
-            # Error with 429 if more than reject_limit requests are queued
-            reject_limit=1,
-            # Allow 1 request at a time
-            concurrent_requests=1,
+            FederationRateLimitConfig(
+                # Time window of 2s
+                window_size=2000,
+                # Artificially delay requests if rate > sleep_limit/window_size
+                sleep_limit=1,
+                # Amount of artificial delay to apply
+                sleep_msec=1000,
+                # Error with 429 if more than reject_limit requests are queued
+                reject_limit=1,
+                # Allow 1 request at a time
+                concurrent_requests=1,
+            )
         )
 
     @defer.inlineCallbacks
diff --git a/synapse/util/ratelimitutils.py b/synapse/util/ratelimitutils.py
index 7deb38f2a7..b146d137f4 100644
--- a/synapse/util/ratelimitutils.py
+++ b/synapse/util/ratelimitutils.py
@@ -30,31 +30,14 @@ logger = logging.getLogger(__name__)
 
 
 class FederationRateLimiter(object):
-    def __init__(self, clock, window_size, sleep_limit, sleep_msec,
-                 reject_limit, concurrent_requests):
+    def __init__(self, clock, config):
         """
         Args:
             clock (Clock)
-            window_size (int): The window size in milliseconds.
-            sleep_limit (int): The number of requests received in the last
-                `window_size` milliseconds before we artificially start
-                delaying processing of requests.
-            sleep_msec (int): The number of milliseconds to delay processing
-                of incoming requests by.
-            reject_limit (int): The maximum number of requests that are can be
-                queued for processing before we start rejecting requests with
-                a 429 Too Many Requests response.
-            concurrent_requests (int): The number of concurrent requests to
-                process.
+            config (FederationRateLimitConfig)
         """
         self.clock = clock
-
-        self.window_size = window_size
-        self.sleep_limit = sleep_limit
-        self.sleep_msec = sleep_msec
-        self.reject_limit = reject_limit
-        self.concurrent_requests = concurrent_requests
-
+        self._config = config
         self.ratelimiters = {}
 
     def ratelimit(self, host):
@@ -76,25 +59,25 @@ class FederationRateLimiter(object):
             host,
             _PerHostRatelimiter(
                 clock=self.clock,
-                window_size=self.window_size,
-                sleep_limit=self.sleep_limit,
-                sleep_msec=self.sleep_msec,
-                reject_limit=self.reject_limit,
-                concurrent_requests=self.concurrent_requests,
+                config=self._config,
             )
         ).ratelimit()
 
 
 class _PerHostRatelimiter(object):
-    def __init__(self, clock, window_size, sleep_limit, sleep_msec,
-                 reject_limit, concurrent_requests):
+    def __init__(self, clock, config):
+        """
+        Args:
+            clock (Clock)
+            config (FederationRateLimitConfig)
+        """
         self.clock = clock
 
-        self.window_size = window_size
-        self.sleep_limit = sleep_limit
-        self.sleep_sec = sleep_msec / 1000.0
-        self.reject_limit = reject_limit
-        self.concurrent_requests = concurrent_requests
+        self.window_size = config.window_size
+        self.sleep_limit = config.sleep_limit
+        self.sleep_sec = config.sleep_delay / 1000.0
+        self.reject_limit = config.reject_limit
+        self.concurrent_requests = config.concurrent
 
         # request_id objects for requests which have been slept
         self.sleeping_requests = set()
diff --git a/tests/utils.py b/tests/utils.py
index f38533a0c7..200c1ceabe 100644
--- a/tests/utils.py
+++ b/tests/utils.py
@@ -134,10 +134,6 @@ def default_config(name, parse=False):
         "email_enable_notifs": False,
         "block_non_admin_invites": False,
         "federation_domain_whitelist": None,
-        "federation_rc_reject_limit": 10,
-        "federation_rc_sleep_limit": 10,
-        "federation_rc_sleep_delay": 100,
-        "federation_rc_concurrent": 10,
         "filter_timeline_limit": 5000,
         "user_directory_search_all_users": False,
         "user_consent_server_notice_content": None,
@@ -156,8 +152,13 @@ def default_config(name, parse=False):
         "mau_stats_only": False,
         "mau_limits_reserved_threepids": [],
         "admin_contact": None,
-        "rc_messages_per_second": 10000,
-        "rc_message_burst_count": 10000,
+        "rc_federation": {
+            "reject_limit": 10,
+            "sleep_limit": 10,
+            "sleep_delay": 10,
+            "concurrent": 10,
+        },
+        "rc_message": {"per_second": 10000, "burst_count": 10000},
         "rc_registration": {"per_second": 10000, "burst_count": 10000},
         "rc_login": {
             "address": {"per_second": 10000, "burst_count": 10000},
@@ -375,12 +376,7 @@ def register_federation_servlets(hs, resource):
         resource=resource,
         authenticator=federation_server.Authenticator(hs),
         ratelimiter=FederationRateLimiter(
-            hs.get_clock(),
-            window_size=hs.config.federation_rc_window_size,
-            sleep_limit=hs.config.federation_rc_sleep_limit,
-            sleep_msec=hs.config.federation_rc_sleep_delay,
-            reject_limit=hs.config.federation_rc_reject_limit,
-            concurrent_requests=hs.config.federation_rc_concurrent,
+            hs.get_clock(), config=hs.config.rc_federation
         ),
     )