823 lines
		
	
	
		
			32 KiB
		
	
	
	
		
			Python
		
	
	
			
		
		
	
	
			823 lines
		
	
	
		
			32 KiB
		
	
	
	
		
			Python
		
	
	
| # Copyright 2017 New Vector Ltd
 | |
| # Copyright 2019 The Matrix.org Foundation C.I.C.
 | |
| #
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| # Licensed under the Apache License, Version 2.0 (the "License");
 | |
| # you may not use this file except in compliance with the License.
 | |
| # You may obtain a copy of the License at
 | |
| #
 | |
| #     http://www.apache.org/licenses/LICENSE-2.0
 | |
| #
 | |
| # Unless required by applicable law or agreed to in writing, software
 | |
| # distributed under the License is distributed on an "AS IS" BASIS,
 | |
| # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 | |
| # See the License for the specific language governing permissions and
 | |
| # limitations under the License.
 | |
| 
 | |
| import inspect
 | |
| import logging
 | |
| from typing import (
 | |
|     TYPE_CHECKING,
 | |
|     Any,
 | |
|     Awaitable,
 | |
|     Callable,
 | |
|     Collection,
 | |
|     List,
 | |
|     Optional,
 | |
|     Tuple,
 | |
|     Union,
 | |
| )
 | |
| 
 | |
| # `Literal` appears with Python 3.8.
 | |
| from typing_extensions import Literal
 | |
| 
 | |
| import synapse
 | |
| from synapse.api.errors import Codes
 | |
| from synapse.logging.opentracing import trace
 | |
| from synapse.rest.media.v1._base import FileInfo
 | |
| from synapse.rest.media.v1.media_storage import ReadableFileWrapper
 | |
| from synapse.spam_checker_api import RegistrationBehaviour
 | |
| from synapse.types import JsonDict, RoomAlias, UserProfile
 | |
| from synapse.util.async_helpers import delay_cancellation, maybe_awaitable
 | |
| from synapse.util.metrics import Measure
 | |
| 
 | |
| if TYPE_CHECKING:
 | |
|     import synapse.events
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|     import synapse.server
 | |
| 
 | |
| logger = logging.getLogger(__name__)
 | |
| 
 | |
| CHECK_EVENT_FOR_SPAM_CALLBACK = Callable[
 | |
|     ["synapse.events.EventBase"],
 | |
|     Awaitable[
 | |
|         Union[
 | |
|             str,
 | |
|             Codes,
 | |
|             # Highly experimental, not officially part of the spamchecker API, may
 | |
|             # disappear without warning depending on the results of ongoing
 | |
|             # experiments.
 | |
|             # Use this to return additional information as part of an error.
 | |
|             Tuple[Codes, JsonDict],
 | |
|             # Deprecated
 | |
|             bool,
 | |
|         ]
 | |
|     ],
 | |
| ]
 | |
| SHOULD_DROP_FEDERATED_EVENT_CALLBACK = Callable[
 | |
|     ["synapse.events.EventBase"],
 | |
|     Awaitable[Union[bool, str]],
 | |
| ]
 | |
| USER_MAY_JOIN_ROOM_CALLBACK = Callable[
 | |
|     [str, str, bool],
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|     Awaitable[
 | |
|         Union[
 | |
|             Literal["NOT_SPAM"],
 | |
|             Codes,
 | |
|             # Highly experimental, not officially part of the spamchecker API, may
 | |
|             # disappear without warning depending on the results of ongoing
 | |
|             # experiments.
 | |
|             # Use this to return additional information as part of an error.
 | |
|             Tuple[Codes, JsonDict],
 | |
|             # Deprecated
 | |
|             bool,
 | |
|         ]
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|     ],
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| ]
 | |
| USER_MAY_INVITE_CALLBACK = Callable[
 | |
|     [str, str, str],
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|     Awaitable[
 | |
|         Union[
 | |
|             Literal["NOT_SPAM"],
 | |
|             Codes,
 | |
|             # Highly experimental, not officially part of the spamchecker API, may
 | |
|             # disappear without warning depending on the results of ongoing
 | |
|             # experiments.
 | |
|             # Use this to return additional information as part of an error.
 | |
|             Tuple[Codes, JsonDict],
 | |
|             # Deprecated
 | |
|             bool,
 | |
|         ]
 | |
|     ],
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| ]
 | |
| USER_MAY_SEND_3PID_INVITE_CALLBACK = Callable[
 | |
|     [str, str, str, str],
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|     Awaitable[
 | |
|         Union[
 | |
|             Literal["NOT_SPAM"],
 | |
|             Codes,
 | |
|             # Highly experimental, not officially part of the spamchecker API, may
 | |
|             # disappear without warning depending on the results of ongoing
 | |
|             # experiments.
 | |
|             # Use this to return additional information as part of an error.
 | |
|             Tuple[Codes, JsonDict],
 | |
|             # Deprecated
 | |
|             bool,
 | |
|         ]
 | |
|     ],
 | |
| ]
 | |
| USER_MAY_CREATE_ROOM_CALLBACK = Callable[
 | |
|     [str],
 | |
|     Awaitable[
 | |
|         Union[
 | |
|             Literal["NOT_SPAM"],
 | |
|             Codes,
 | |
|             # Highly experimental, not officially part of the spamchecker API, may
 | |
|             # disappear without warning depending on the results of ongoing
 | |
|             # experiments.
 | |
|             # Use this to return additional information as part of an error.
 | |
|             Tuple[Codes, JsonDict],
 | |
|             # Deprecated
 | |
|             bool,
 | |
|         ]
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|     ],
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| ]
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| USER_MAY_CREATE_ROOM_ALIAS_CALLBACK = Callable[
 | |
|     [str, RoomAlias],
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|     Awaitable[
 | |
|         Union[
 | |
|             Literal["NOT_SPAM"],
 | |
|             Codes,
 | |
|             # Highly experimental, not officially part of the spamchecker API, may
 | |
|             # disappear without warning depending on the results of ongoing
 | |
|             # experiments.
 | |
|             # Use this to return additional information as part of an error.
 | |
|             Tuple[Codes, JsonDict],
 | |
|             # Deprecated
 | |
|             bool,
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|         ]
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|     ],
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| ]
 | |
| USER_MAY_PUBLISH_ROOM_CALLBACK = Callable[
 | |
|     [str, str],
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|     Awaitable[
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|         Union[
 | |
|             Literal["NOT_SPAM"],
 | |
|             Codes,
 | |
|             # Highly experimental, not officially part of the spamchecker API, may
 | |
|             # disappear without warning depending on the results of ongoing
 | |
|             # experiments.
 | |
|             # Use this to return additional information as part of an error.
 | |
|             Tuple[Codes, JsonDict],
 | |
|             # Deprecated
 | |
|             bool,
 | |
|         ]
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|     ],
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| ]
 | |
| CHECK_USERNAME_FOR_SPAM_CALLBACK = Callable[[UserProfile], Awaitable[bool]]
 | |
| LEGACY_CHECK_REGISTRATION_FOR_SPAM_CALLBACK = Callable[
 | |
|     [
 | |
|         Optional[dict],
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|         Optional[str],
 | |
|         Collection[Tuple[str, str]],
 | |
|     ],
 | |
|     Awaitable[RegistrationBehaviour],
 | |
| ]
 | |
| CHECK_REGISTRATION_FOR_SPAM_CALLBACK = Callable[
 | |
|     [
 | |
|         Optional[dict],
 | |
|         Optional[str],
 | |
|         Collection[Tuple[str, str]],
 | |
|         Optional[str],
 | |
|     ],
 | |
|     Awaitable[RegistrationBehaviour],
 | |
| ]
 | |
| CHECK_MEDIA_FILE_FOR_SPAM_CALLBACK = Callable[
 | |
|     [ReadableFileWrapper, FileInfo],
 | |
|     Awaitable[
 | |
|         Union[
 | |
|             Literal["NOT_SPAM"],
 | |
|             Codes,
 | |
|             # Highly experimental, not officially part of the spamchecker API, may
 | |
|             # disappear without warning depending on the results of ongoing
 | |
|             # experiments.
 | |
|             # Use this to return additional information as part of an error.
 | |
|             Tuple[Codes, JsonDict],
 | |
|             # Deprecated
 | |
|             bool,
 | |
|         ]
 | |
|     ],
 | |
| ]
 | |
| 
 | |
| 
 | |
| def load_legacy_spam_checkers(hs: "synapse.server.HomeServer") -> None:
 | |
|     """Wrapper that loads spam checkers configured using the old configuration, and
 | |
|     registers the spam checker hooks they implement.
 | |
|     """
 | |
|     spam_checkers: List[Any] = []
 | |
|     api = hs.get_module_api()
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|     for module, config in hs.config.spamchecker.spam_checkers:
 | |
|         # Older spam checkers don't accept the `api` argument, so we
 | |
|         # try and detect support.
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|         spam_args = inspect.getfullargspec(module)
 | |
|         if "api" in spam_args.args:
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|             spam_checkers.append(module(config=config, api=api))
 | |
|         else:
 | |
|             spam_checkers.append(module(config=config))
 | |
| 
 | |
|     # The known spam checker hooks. If a spam checker module implements a method
 | |
|     # which name appears in this set, we'll want to register it.
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|     spam_checker_methods = {
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|         "check_event_for_spam",
 | |
|         "user_may_invite",
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|         "user_may_create_room",
 | |
|         "user_may_create_room_alias",
 | |
|         "user_may_publish_room",
 | |
|         "check_username_for_spam",
 | |
|         "check_registration_for_spam",
 | |
|         "check_media_file_for_spam",
 | |
|     }
 | |
| 
 | |
|     for spam_checker in spam_checkers:
 | |
|         # Methods on legacy spam checkers might not be async, so we wrap them around a
 | |
|         # wrapper that will call maybe_awaitable on the result.
 | |
|         def async_wrapper(f: Optional[Callable]) -> Optional[Callable[..., Awaitable]]:
 | |
|             # f might be None if the callback isn't implemented by the module. In this
 | |
|             # case we don't want to register a callback at all so we return None.
 | |
|             if f is None:
 | |
|                 return None
 | |
| 
 | |
|             wrapped_func = f
 | |
| 
 | |
|             if f.__name__ == "check_registration_for_spam":
 | |
|                 checker_args = inspect.signature(f)
 | |
|                 if len(checker_args.parameters) == 3:
 | |
|                     # Backwards compatibility; some modules might implement a hook that
 | |
|                     # doesn't expect a 4th argument. In this case, wrap it in a function
 | |
|                     # that gives it only 3 arguments and drops the auth_provider_id on
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|                     # the floor.
 | |
|                     def wrapper(
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|                         email_threepid: Optional[dict],
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|                         username: Optional[str],
 | |
|                         request_info: Collection[Tuple[str, str]],
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|                         auth_provider_id: Optional[str],
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|                     ) -> Union[Awaitable[RegistrationBehaviour], RegistrationBehaviour]:
 | |
|                         # Assertion required because mypy can't prove we won't
 | |
|                         # change `f` back to `None`. See
 | |
|                         # https://mypy.readthedocs.io/en/latest/common_issues.html#narrowing-and-inner-functions
 | |
|                         assert f is not None
 | |
| 
 | |
|                         return f(
 | |
|                             email_threepid,
 | |
|                             username,
 | |
|                             request_info,
 | |
|                         )
 | |
| 
 | |
|                     wrapped_func = wrapper
 | |
|                 elif len(checker_args.parameters) != 4:
 | |
|                     raise RuntimeError(
 | |
|                         "Bad signature for callback check_registration_for_spam",
 | |
|                     )
 | |
| 
 | |
|             def run(*args: Any, **kwargs: Any) -> Awaitable:
 | |
|                 # Assertion required because mypy can't prove we won't change `f`
 | |
|                 # back to `None`. See
 | |
|                 # https://mypy.readthedocs.io/en/latest/common_issues.html#narrowing-and-inner-functions
 | |
|                 assert wrapped_func is not None
 | |
| 
 | |
|                 return maybe_awaitable(wrapped_func(*args, **kwargs))
 | |
| 
 | |
|             return run
 | |
| 
 | |
|         # Register the hooks through the module API.
 | |
|         hooks = {
 | |
|             hook: async_wrapper(getattr(spam_checker, hook, None))
 | |
|             for hook in spam_checker_methods
 | |
|         }
 | |
| 
 | |
|         api.register_spam_checker_callbacks(**hooks)
 | |
| 
 | |
| 
 | |
| class SpamChecker:
 | |
|     NOT_SPAM: Literal["NOT_SPAM"] = "NOT_SPAM"
 | |
| 
 | |
|     def __init__(self, hs: "synapse.server.HomeServer") -> None:
 | |
|         self.hs = hs
 | |
|         self.clock = hs.get_clock()
 | |
| 
 | |
|         self._check_event_for_spam_callbacks: List[CHECK_EVENT_FOR_SPAM_CALLBACK] = []
 | |
|         self._should_drop_federated_event_callbacks: List[
 | |
|             SHOULD_DROP_FEDERATED_EVENT_CALLBACK
 | |
|         ] = []
 | |
|         self._user_may_join_room_callbacks: List[USER_MAY_JOIN_ROOM_CALLBACK] = []
 | |
|         self._user_may_invite_callbacks: List[USER_MAY_INVITE_CALLBACK] = []
 | |
|         self._user_may_send_3pid_invite_callbacks: List[
 | |
|             USER_MAY_SEND_3PID_INVITE_CALLBACK
 | |
|         ] = []
 | |
|         self._user_may_create_room_callbacks: List[USER_MAY_CREATE_ROOM_CALLBACK] = []
 | |
|         self._user_may_create_room_alias_callbacks: List[
 | |
|             USER_MAY_CREATE_ROOM_ALIAS_CALLBACK
 | |
|         ] = []
 | |
|         self._user_may_publish_room_callbacks: List[USER_MAY_PUBLISH_ROOM_CALLBACK] = []
 | |
|         self._check_username_for_spam_callbacks: List[
 | |
|             CHECK_USERNAME_FOR_SPAM_CALLBACK
 | |
|         ] = []
 | |
|         self._check_registration_for_spam_callbacks: List[
 | |
|             CHECK_REGISTRATION_FOR_SPAM_CALLBACK
 | |
|         ] = []
 | |
|         self._check_media_file_for_spam_callbacks: List[
 | |
|             CHECK_MEDIA_FILE_FOR_SPAM_CALLBACK
 | |
|         ] = []
 | |
| 
 | |
|     def register_callbacks(
 | |
|         self,
 | |
|         check_event_for_spam: Optional[CHECK_EVENT_FOR_SPAM_CALLBACK] = None,
 | |
|         should_drop_federated_event: Optional[
 | |
|             SHOULD_DROP_FEDERATED_EVENT_CALLBACK
 | |
|         ] = None,
 | |
|         user_may_join_room: Optional[USER_MAY_JOIN_ROOM_CALLBACK] = None,
 | |
|         user_may_invite: Optional[USER_MAY_INVITE_CALLBACK] = None,
 | |
|         user_may_send_3pid_invite: Optional[USER_MAY_SEND_3PID_INVITE_CALLBACK] = None,
 | |
|         user_may_create_room: Optional[USER_MAY_CREATE_ROOM_CALLBACK] = None,
 | |
|         user_may_create_room_alias: Optional[
 | |
|             USER_MAY_CREATE_ROOM_ALIAS_CALLBACK
 | |
|         ] = None,
 | |
|         user_may_publish_room: Optional[USER_MAY_PUBLISH_ROOM_CALLBACK] = None,
 | |
|         check_username_for_spam: Optional[CHECK_USERNAME_FOR_SPAM_CALLBACK] = None,
 | |
|         check_registration_for_spam: Optional[
 | |
|             CHECK_REGISTRATION_FOR_SPAM_CALLBACK
 | |
|         ] = None,
 | |
|         check_media_file_for_spam: Optional[CHECK_MEDIA_FILE_FOR_SPAM_CALLBACK] = None,
 | |
|     ) -> None:
 | |
|         """Register callbacks from module for each hook."""
 | |
|         if check_event_for_spam is not None:
 | |
|             self._check_event_for_spam_callbacks.append(check_event_for_spam)
 | |
| 
 | |
|         if should_drop_federated_event is not None:
 | |
|             self._should_drop_federated_event_callbacks.append(
 | |
|                 should_drop_federated_event
 | |
|             )
 | |
| 
 | |
|         if user_may_join_room is not None:
 | |
|             self._user_may_join_room_callbacks.append(user_may_join_room)
 | |
| 
 | |
|         if user_may_invite is not None:
 | |
|             self._user_may_invite_callbacks.append(user_may_invite)
 | |
| 
 | |
|         if user_may_send_3pid_invite is not None:
 | |
|             self._user_may_send_3pid_invite_callbacks.append(
 | |
|                 user_may_send_3pid_invite,
 | |
|             )
 | |
| 
 | |
|         if user_may_create_room is not None:
 | |
|             self._user_may_create_room_callbacks.append(user_may_create_room)
 | |
| 
 | |
|         if user_may_create_room_alias is not None:
 | |
|             self._user_may_create_room_alias_callbacks.append(
 | |
|                 user_may_create_room_alias,
 | |
|             )
 | |
| 
 | |
|         if user_may_publish_room is not None:
 | |
|             self._user_may_publish_room_callbacks.append(user_may_publish_room)
 | |
| 
 | |
|         if check_username_for_spam is not None:
 | |
|             self._check_username_for_spam_callbacks.append(check_username_for_spam)
 | |
| 
 | |
|         if check_registration_for_spam is not None:
 | |
|             self._check_registration_for_spam_callbacks.append(
 | |
|                 check_registration_for_spam,
 | |
|             )
 | |
| 
 | |
|         if check_media_file_for_spam is not None:
 | |
|             self._check_media_file_for_spam_callbacks.append(check_media_file_for_spam)
 | |
| 
 | |
|     @trace
 | |
|     async def check_event_for_spam(
 | |
|         self, event: "synapse.events.EventBase"
 | |
|     ) -> Union[Tuple[Codes, JsonDict], str]:
 | |
|         """Checks if a given event is considered "spammy" by this server.
 | |
| 
 | |
|         If the server considers an event spammy, then it will be rejected if
 | |
|         sent by a local user. If it is sent by a user on another server, the
 | |
|         event is soft-failed.
 | |
| 
 | |
|         Args:
 | |
|             event: the event to be checked
 | |
| 
 | |
|         Returns:
 | |
|             - `NOT_SPAM` if the event is considered good (non-spammy) and should be let
 | |
|                 through. Other spamcheck filters may still reject it.
 | |
|             - A `Code` if the event is considered spammy and is rejected with a specific
 | |
|                 error message/code.
 | |
|             - A string that isn't `NOT_SPAM` if the event is considered spammy and the
 | |
|                 string should be used as the client-facing error message. This usage is
 | |
|                 generally discouraged as it doesn't support internationalization.
 | |
|         """
 | |
|         for callback in self._check_event_for_spam_callbacks:
 | |
|             with Measure(
 | |
|                 self.clock, "{}.{}".format(callback.__module__, callback.__qualname__)
 | |
|             ):
 | |
|                 res = await delay_cancellation(callback(event))
 | |
|                 if res is False or res == self.NOT_SPAM:
 | |
|                     # This spam-checker accepts the event.
 | |
|                     # Other spam-checkers may reject it, though.
 | |
|                     continue
 | |
|                 elif res is True:
 | |
|                     # This spam-checker rejects the event with deprecated
 | |
|                     # return value `True`
 | |
|                     return synapse.api.errors.Codes.FORBIDDEN, {}
 | |
|                 elif (
 | |
|                     isinstance(res, tuple)
 | |
|                     and len(res) == 2
 | |
|                     and isinstance(res[0], synapse.api.errors.Codes)
 | |
|                     and isinstance(res[1], dict)
 | |
|                 ):
 | |
|                     return res
 | |
|                 elif isinstance(res, synapse.api.errors.Codes):
 | |
|                     return res, {}
 | |
|                 elif not isinstance(res, str):
 | |
|                     # mypy complains that we can't reach this code because of the
 | |
|                     # return type in CHECK_EVENT_FOR_SPAM_CALLBACK, but we don't know
 | |
|                     # for sure that the module actually returns it.
 | |
|                     logger.warning(
 | |
|                         "Module returned invalid value, rejecting message as spam"
 | |
|                     )
 | |
|                     res = "This message has been rejected as probable spam"
 | |
|                 else:
 | |
|                     # The module rejected the event either with a `Codes`
 | |
|                     # or some other `str`. In either case, we stop here.
 | |
|                     pass
 | |
| 
 | |
|                 return res
 | |
| 
 | |
|         # No spam-checker has rejected the event, let it pass.
 | |
|         return self.NOT_SPAM
 | |
| 
 | |
|     async def should_drop_federated_event(
 | |
|         self, event: "synapse.events.EventBase"
 | |
|     ) -> Union[bool, str]:
 | |
|         """Checks if a given federated event is considered "spammy" by this
 | |
|         server.
 | |
| 
 | |
|         If the server considers an event spammy, it will be silently dropped,
 | |
|         and in doing so will split-brain our view of the room's DAG.
 | |
| 
 | |
|         Args:
 | |
|             event: the event to be checked
 | |
| 
 | |
|         Returns:
 | |
|             True if the event should be silently dropped
 | |
|         """
 | |
|         for callback in self._should_drop_federated_event_callbacks:
 | |
|             with Measure(
 | |
|                 self.clock, "{}.{}".format(callback.__module__, callback.__qualname__)
 | |
|             ):
 | |
|                 res: Union[bool, str] = await delay_cancellation(callback(event))
 | |
|             if res:
 | |
|                 return res
 | |
| 
 | |
|         return False
 | |
| 
 | |
|     async def user_may_join_room(
 | |
|         self, user_id: str, room_id: str, is_invited: bool
 | |
|     ) -> Union[Tuple[Codes, JsonDict], Literal["NOT_SPAM"]]:
 | |
|         """Checks if a given users is allowed to join a room.
 | |
|         Not called when a user creates a room.
 | |
| 
 | |
|         Args:
 | |
|             userid: The ID of the user wanting to join the room
 | |
|             room_id: The ID of the room the user wants to join
 | |
|             is_invited: Whether the user is invited into the room
 | |
| 
 | |
|         Returns:
 | |
|             NOT_SPAM if the operation is permitted, [Codes, Dict] otherwise.
 | |
|         """
 | |
|         for callback in self._user_may_join_room_callbacks:
 | |
|             with Measure(
 | |
|                 self.clock, "{}.{}".format(callback.__module__, callback.__qualname__)
 | |
|             ):
 | |
|                 res = await delay_cancellation(callback(user_id, room_id, is_invited))
 | |
|                 # Normalize return values to `Codes` or `"NOT_SPAM"`.
 | |
|                 if res is True or res is self.NOT_SPAM:
 | |
|                     continue
 | |
|                 elif res is False:
 | |
|                     return synapse.api.errors.Codes.FORBIDDEN, {}
 | |
|                 elif isinstance(res, synapse.api.errors.Codes):
 | |
|                     return res, {}
 | |
|                 elif (
 | |
|                     isinstance(res, tuple)
 | |
|                     and len(res) == 2
 | |
|                     and isinstance(res[0], synapse.api.errors.Codes)
 | |
|                     and isinstance(res[1], dict)
 | |
|                 ):
 | |
|                     return res
 | |
|                 else:
 | |
|                     logger.warning(
 | |
|                         "Module returned invalid value, rejecting join as spam"
 | |
|                     )
 | |
|                     return synapse.api.errors.Codes.FORBIDDEN, {}
 | |
| 
 | |
|         # No spam-checker has rejected the request, let it pass.
 | |
|         return self.NOT_SPAM
 | |
| 
 | |
|     async def user_may_invite(
 | |
|         self, inviter_userid: str, invitee_userid: str, room_id: str
 | |
|     ) -> Union[Tuple[Codes, dict], Literal["NOT_SPAM"]]:
 | |
|         """Checks if a given user may send an invite
 | |
| 
 | |
|         Args:
 | |
|             inviter_userid: The user ID of the sender of the invitation
 | |
|             invitee_userid: The user ID targeted in the invitation
 | |
|             room_id: The room ID
 | |
| 
 | |
|         Returns:
 | |
|             NOT_SPAM if the operation is permitted, Codes otherwise.
 | |
|         """
 | |
|         for callback in self._user_may_invite_callbacks:
 | |
|             with Measure(
 | |
|                 self.clock, "{}.{}".format(callback.__module__, callback.__qualname__)
 | |
|             ):
 | |
|                 res = await delay_cancellation(
 | |
|                     callback(inviter_userid, invitee_userid, room_id)
 | |
|                 )
 | |
|                 # Normalize return values to `Codes` or `"NOT_SPAM"`.
 | |
|                 if res is True or res is self.NOT_SPAM:
 | |
|                     continue
 | |
|                 elif res is False:
 | |
|                     return synapse.api.errors.Codes.FORBIDDEN, {}
 | |
|                 elif isinstance(res, synapse.api.errors.Codes):
 | |
|                     return res, {}
 | |
|                 elif (
 | |
|                     isinstance(res, tuple)
 | |
|                     and len(res) == 2
 | |
|                     and isinstance(res[0], synapse.api.errors.Codes)
 | |
|                     and isinstance(res[1], dict)
 | |
|                 ):
 | |
|                     return res
 | |
|                 else:
 | |
|                     logger.warning(
 | |
|                         "Module returned invalid value, rejecting invite as spam"
 | |
|                     )
 | |
|                     return synapse.api.errors.Codes.FORBIDDEN, {}
 | |
| 
 | |
|         # No spam-checker has rejected the request, let it pass.
 | |
|         return self.NOT_SPAM
 | |
| 
 | |
|     async def user_may_send_3pid_invite(
 | |
|         self, inviter_userid: str, medium: str, address: str, room_id: str
 | |
|     ) -> Union[Tuple[Codes, dict], Literal["NOT_SPAM"]]:
 | |
|         """Checks if a given user may invite a given threepid into the room
 | |
| 
 | |
|         Note that if the threepid is already associated with a Matrix user ID, Synapse
 | |
|         will call user_may_invite with said user ID instead.
 | |
| 
 | |
|         Args:
 | |
|             inviter_userid: The user ID of the sender of the invitation
 | |
|             medium: The 3PID's medium (e.g. "email")
 | |
|             address: The 3PID's address (e.g. "alice@example.com")
 | |
|             room_id: The room ID
 | |
| 
 | |
|         Returns:
 | |
|             NOT_SPAM if the operation is permitted, Codes otherwise.
 | |
|         """
 | |
|         for callback in self._user_may_send_3pid_invite_callbacks:
 | |
|             with Measure(
 | |
|                 self.clock, "{}.{}".format(callback.__module__, callback.__qualname__)
 | |
|             ):
 | |
|                 res = await delay_cancellation(
 | |
|                     callback(inviter_userid, medium, address, room_id)
 | |
|                 )
 | |
|                 # Normalize return values to `Codes` or `"NOT_SPAM"`.
 | |
|                 if res is True or res is self.NOT_SPAM:
 | |
|                     continue
 | |
|                 elif res is False:
 | |
|                     return synapse.api.errors.Codes.FORBIDDEN, {}
 | |
|                 elif isinstance(res, synapse.api.errors.Codes):
 | |
|                     return res, {}
 | |
|                 elif (
 | |
|                     isinstance(res, tuple)
 | |
|                     and len(res) == 2
 | |
|                     and isinstance(res[0], synapse.api.errors.Codes)
 | |
|                     and isinstance(res[1], dict)
 | |
|                 ):
 | |
|                     return res
 | |
|                 else:
 | |
|                     logger.warning(
 | |
|                         "Module returned invalid value, rejecting 3pid invite as spam"
 | |
|                     )
 | |
|                     return synapse.api.errors.Codes.FORBIDDEN, {}
 | |
| 
 | |
|         return self.NOT_SPAM
 | |
| 
 | |
|     async def user_may_create_room(
 | |
|         self, userid: str
 | |
|     ) -> Union[Tuple[Codes, dict], Literal["NOT_SPAM"]]:
 | |
|         """Checks if a given user may create a room
 | |
| 
 | |
|         Args:
 | |
|             userid: The ID of the user attempting to create a room
 | |
|         """
 | |
|         for callback in self._user_may_create_room_callbacks:
 | |
|             with Measure(
 | |
|                 self.clock, "{}.{}".format(callback.__module__, callback.__qualname__)
 | |
|             ):
 | |
|                 res = await delay_cancellation(callback(userid))
 | |
|                 if res is True or res is self.NOT_SPAM:
 | |
|                     continue
 | |
|                 elif res is False:
 | |
|                     return synapse.api.errors.Codes.FORBIDDEN, {}
 | |
|                 elif isinstance(res, synapse.api.errors.Codes):
 | |
|                     return res, {}
 | |
|                 elif (
 | |
|                     isinstance(res, tuple)
 | |
|                     and len(res) == 2
 | |
|                     and isinstance(res[0], synapse.api.errors.Codes)
 | |
|                     and isinstance(res[1], dict)
 | |
|                 ):
 | |
|                     return res
 | |
|                 else:
 | |
|                     logger.warning(
 | |
|                         "Module returned invalid value, rejecting room creation as spam"
 | |
|                     )
 | |
|                     return synapse.api.errors.Codes.FORBIDDEN, {}
 | |
| 
 | |
|         return self.NOT_SPAM
 | |
| 
 | |
|     async def user_may_create_room_alias(
 | |
|         self, userid: str, room_alias: RoomAlias
 | |
|     ) -> Union[Tuple[Codes, dict], Literal["NOT_SPAM"]]:
 | |
|         """Checks if a given user may create a room alias
 | |
| 
 | |
|         Args:
 | |
|             userid: The ID of the user attempting to create a room alias
 | |
|             room_alias: The alias to be created
 | |
| 
 | |
|         """
 | |
|         for callback in self._user_may_create_room_alias_callbacks:
 | |
|             with Measure(
 | |
|                 self.clock, "{}.{}".format(callback.__module__, callback.__qualname__)
 | |
|             ):
 | |
|                 res = await delay_cancellation(callback(userid, room_alias))
 | |
|                 if res is True or res is self.NOT_SPAM:
 | |
|                     continue
 | |
|                 elif res is False:
 | |
|                     return synapse.api.errors.Codes.FORBIDDEN, {}
 | |
|                 elif isinstance(res, synapse.api.errors.Codes):
 | |
|                     return res, {}
 | |
|                 elif (
 | |
|                     isinstance(res, tuple)
 | |
|                     and len(res) == 2
 | |
|                     and isinstance(res[0], synapse.api.errors.Codes)
 | |
|                     and isinstance(res[1], dict)
 | |
|                 ):
 | |
|                     return res
 | |
|                 else:
 | |
|                     logger.warning(
 | |
|                         "Module returned invalid value, rejecting room create as spam"
 | |
|                     )
 | |
|                     return synapse.api.errors.Codes.FORBIDDEN, {}
 | |
| 
 | |
|         return self.NOT_SPAM
 | |
| 
 | |
|     async def user_may_publish_room(
 | |
|         self, userid: str, room_id: str
 | |
|     ) -> Union[Tuple[Codes, dict], Literal["NOT_SPAM"]]:
 | |
|         """Checks if a given user may publish a room to the directory
 | |
| 
 | |
|         Args:
 | |
|             userid: The user ID attempting to publish the room
 | |
|             room_id: The ID of the room that would be published
 | |
|         """
 | |
|         for callback in self._user_may_publish_room_callbacks:
 | |
|             with Measure(
 | |
|                 self.clock, "{}.{}".format(callback.__module__, callback.__qualname__)
 | |
|             ):
 | |
|                 res = await delay_cancellation(callback(userid, room_id))
 | |
|                 if res is True or res is self.NOT_SPAM:
 | |
|                     continue
 | |
|                 elif res is False:
 | |
|                     return synapse.api.errors.Codes.FORBIDDEN, {}
 | |
|                 elif isinstance(res, synapse.api.errors.Codes):
 | |
|                     return res, {}
 | |
|                 elif (
 | |
|                     isinstance(res, tuple)
 | |
|                     and len(res) == 2
 | |
|                     and isinstance(res[0], synapse.api.errors.Codes)
 | |
|                     and isinstance(res[1], dict)
 | |
|                 ):
 | |
|                     return res
 | |
|                 else:
 | |
|                     logger.warning(
 | |
|                         "Module returned invalid value, rejecting room publication as spam"
 | |
|                     )
 | |
|                     return synapse.api.errors.Codes.FORBIDDEN, {}
 | |
| 
 | |
|         return self.NOT_SPAM
 | |
| 
 | |
|     async def check_username_for_spam(self, user_profile: UserProfile) -> bool:
 | |
|         """Checks if a user ID or display name are considered "spammy" by this server.
 | |
| 
 | |
|         If the server considers a username spammy, then it will not be included in
 | |
|         user directory results.
 | |
| 
 | |
|         Args:
 | |
|             user_profile: The user information to check, it contains the keys:
 | |
|                 * user_id
 | |
|                 * display_name
 | |
|                 * avatar_url
 | |
| 
 | |
|         Returns:
 | |
|             True if the user is spammy.
 | |
|         """
 | |
|         for callback in self._check_username_for_spam_callbacks:
 | |
|             with Measure(
 | |
|                 self.clock, "{}.{}".format(callback.__module__, callback.__qualname__)
 | |
|             ):
 | |
|                 # Make a copy of the user profile object to ensure the spam checker cannot
 | |
|                 # modify it.
 | |
|                 res = await delay_cancellation(callback(user_profile.copy()))
 | |
|             if res:
 | |
|                 return True
 | |
| 
 | |
|         return False
 | |
| 
 | |
|     async def check_registration_for_spam(
 | |
|         self,
 | |
|         email_threepid: Optional[dict],
 | |
|         username: Optional[str],
 | |
|         request_info: Collection[Tuple[str, str]],
 | |
|         auth_provider_id: Optional[str] = None,
 | |
|     ) -> RegistrationBehaviour:
 | |
|         """Checks if we should allow the given registration request.
 | |
| 
 | |
|         Args:
 | |
|             email_threepid: The email threepid used for registering, if any
 | |
|             username: The request user name, if any
 | |
|             request_info: List of tuples of user agent and IP that
 | |
|                 were used during the registration process.
 | |
|             auth_provider_id: The SSO IdP the user used, e.g "oidc", "saml",
 | |
|                 "cas". If any. Note this does not include users registered
 | |
|                 via a password provider.
 | |
| 
 | |
|         Returns:
 | |
|             Enum for how the request should be handled
 | |
|         """
 | |
| 
 | |
|         for callback in self._check_registration_for_spam_callbacks:
 | |
|             with Measure(
 | |
|                 self.clock, "{}.{}".format(callback.__module__, callback.__qualname__)
 | |
|             ):
 | |
|                 behaviour = await delay_cancellation(
 | |
|                     callback(email_threepid, username, request_info, auth_provider_id)
 | |
|                 )
 | |
|             assert isinstance(behaviour, RegistrationBehaviour)
 | |
|             if behaviour != RegistrationBehaviour.ALLOW:
 | |
|                 return behaviour
 | |
| 
 | |
|         return RegistrationBehaviour.ALLOW
 | |
| 
 | |
|     async def check_media_file_for_spam(
 | |
|         self, file_wrapper: ReadableFileWrapper, file_info: FileInfo
 | |
|     ) -> Union[Tuple[Codes, dict], Literal["NOT_SPAM"]]:
 | |
|         """Checks if a piece of newly uploaded media should be blocked.
 | |
| 
 | |
|         This will be called for local uploads, downloads of remote media, each
 | |
|         thumbnail generated for those, and web pages/images used for URL
 | |
|         previews.
 | |
| 
 | |
|         Note that care should be taken to not do blocking IO operations in the
 | |
|         main thread. For example, to get the contents of a file a module
 | |
|         should do::
 | |
| 
 | |
|             async def check_media_file_for_spam(
 | |
|                 self, file: ReadableFileWrapper, file_info: FileInfo
 | |
|             ) -> Union[Codes, Literal["NOT_SPAM"]]:
 | |
|                 buffer = BytesIO()
 | |
|                 await file.write_chunks_to(buffer.write)
 | |
| 
 | |
|                 if buffer.getvalue() == b"Hello World":
 | |
|                     return synapse.module_api.NOT_SPAM
 | |
| 
 | |
|                 return Codes.FORBIDDEN
 | |
| 
 | |
| 
 | |
|         Args:
 | |
|             file: An object that allows reading the contents of the media.
 | |
|             file_info: Metadata about the file.
 | |
|         """
 | |
| 
 | |
|         for callback in self._check_media_file_for_spam_callbacks:
 | |
|             with Measure(
 | |
|                 self.clock, "{}.{}".format(callback.__module__, callback.__qualname__)
 | |
|             ):
 | |
|                 res = await delay_cancellation(callback(file_wrapper, file_info))
 | |
|                 # Normalize return values to `Codes` or `"NOT_SPAM"`.
 | |
|                 if res is False or res is self.NOT_SPAM:
 | |
|                     continue
 | |
|                 elif res is True:
 | |
|                     return synapse.api.errors.Codes.FORBIDDEN, {}
 | |
|                 elif isinstance(res, synapse.api.errors.Codes):
 | |
|                     return res, {}
 | |
|                 elif (
 | |
|                     isinstance(res, tuple)
 | |
|                     and len(res) == 2
 | |
|                     and isinstance(res[0], synapse.api.errors.Codes)
 | |
|                     and isinstance(res[1], dict)
 | |
|                 ):
 | |
|                     return res
 | |
|                 else:
 | |
|                     logger.warning(
 | |
|                         "Module returned invalid value, rejecting media file as spam"
 | |
|                     )
 | |
|                     return synapse.api.errors.Codes.FORBIDDEN, {}
 | |
| 
 | |
|         return self.NOT_SPAM
 |