Allow use of different ratelimits for admin redactions.

This is useful to allow room admins to quickly deal with a large number
of abusive messages.
This commit is contained in:
Erik Johnston 2019-09-11 10:46:38 +01:00
parent 5e9b05d7da
commit 54ce81c86d
4 changed files with 55 additions and 11 deletions

View file

@ -80,6 +80,12 @@ class RatelimitConfig(Config):
"federation_rr_transactions_per_room_per_second", 50
)
rc_admin_redaction = config.get("rc_admin_redaction")
if rc_admin_redaction:
self.rc_admin_redaction = RateLimitConfig(rc_admin_redaction)
else:
self.rc_admin_redaction = None
def generate_config_section(self, **kwargs):
return """\
## Ratelimiting ##
@ -102,6 +108,9 @@ class RatelimitConfig(Config):
# - one for login that ratelimits login requests based on the account the
# client is attempting to log into, based on the amount of failed login
# attempts for this account.
# - one for ratelimiting redactions by room admins. If this is not explicitly
# set then it uses the same ratelimiting as per rc_message. This is useful
# to allow room admins to quickly deal with abuse quickly.
#
# The defaults are as shown below.
#
@ -123,6 +132,10 @@ class RatelimitConfig(Config):
# failed_attempts:
# per_second: 0.17
# burst_count: 3
#
#rc_admin_redaction:
# per_second: 1
# burst_count: 50
# Ratelimiting settings for incoming federation

View file

@ -45,6 +45,7 @@ class BaseHandler(object):
self.state_handler = hs.get_state_handler()
self.distributor = hs.get_distributor()
self.ratelimiter = hs.get_ratelimiter()
self.admin_redaction_ratelimiter = hs.get_admin_redaction_ratelimiter()
self.clock = hs.get_clock()
self.hs = hs
@ -53,7 +54,7 @@ class BaseHandler(object):
self.event_builder_factory = hs.get_event_builder_factory()
@defer.inlineCallbacks
def ratelimit(self, requester, update=True):
def ratelimit(self, requester, update=True, is_admin_redaction=False):
"""Ratelimits requests.
Args:
@ -62,6 +63,9 @@ class BaseHandler(object):
Set to False when doing multiple checks for one request (e.g.
to check up front if we would reject the request), and set to
True for the last call for a given request.
is_admin_redaction (bool): Whether this is a room admin/moderator
redacting an event. If so then we may apply different
ratelimits depending on config.
Raises:
LimitExceededError if the request should be ratelimited
@ -90,16 +94,33 @@ class BaseHandler(object):
messages_per_second = override.messages_per_second
burst_count = override.burst_count
else:
messages_per_second = self.hs.config.rc_message.per_second
burst_count = self.hs.config.rc_message.burst_count
# We default to different values if this is an admin redaction and
# the config is set
if is_admin_redaction and self.hs.config.rc_admin_redaction:
messages_per_second = self.hs.config.rc_admin_redaction.per_second
burst_count = self.hs.config.rc_admin_redaction.burst_count
else:
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,
rate_hz=messages_per_second,
burst_count=burst_count,
update=update,
)
if is_admin_redaction and self.hs.config.rc_admin_redaction:
# If we have separate config for admin redactions we use a separate
# ratelimiter.
allowed, time_allowed = self.admin_redaction_ratelimiter.can_do_action(
user_id,
time_now,
rate_hz=messages_per_second,
burst_count=burst_count,
update=update,
)
else:
allowed, time_allowed = self.ratelimiter.can_do_action(
user_id,
time_now,
rate_hz=messages_per_second,
burst_count=burst_count,
update=update,
)
if not allowed:
raise LimitExceededError(
retry_after_ms=int(1000 * (time_allowed - time_now))

View file

@ -729,7 +729,13 @@ class EventCreationHandler(object):
assert not self.config.worker_app
if ratelimit:
yield self.base_handler.ratelimit(requester)
is_admin_redaction = (
event.type == EventTypes.Redaction
and event.sender != requester.user.to_string()
)
yield self.base_handler.ratelimit(
requester, is_admin_redaction=is_admin_redaction
)
yield self.base_handler.maybe_kick_guest_users(event, context)

View file

@ -221,6 +221,7 @@ class HomeServer(object):
self.clock = Clock(reactor)
self.distributor = Distributor()
self.ratelimiter = Ratelimiter()
self.admin_redaction_ratelimiter = Ratelimiter()
self.registration_ratelimiter = Ratelimiter()
self.datastore = None
@ -279,6 +280,9 @@ class HomeServer(object):
def get_registration_ratelimiter(self):
return self.registration_ratelimiter
def get_admin_redaction_ratelimiter(self):
return self.admin_redaction_ratelimiter
def build_federation_client(self):
return FederationClient(self)