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-rw-r--r--synapse/handlers/auth.py388
-rw-r--r--synapse/handlers/identity.py3
-rw-r--r--synapse/handlers/oidc_handler.py30
-rw-r--r--synapse/handlers/pagination.py17
-rw-r--r--synapse/handlers/room_member.py10
-rw-r--r--synapse/handlers/saml_handler.py11
-rw-r--r--synapse/handlers/sso.py60
7 files changed, 388 insertions, 131 deletions
diff --git a/synapse/handlers/auth.py b/synapse/handlers/auth.py

index 5163afd86c..c7dc07008a 100644 --- a/synapse/handlers/auth.py +++ b/synapse/handlers/auth.py
@@ -1,6 +1,7 @@ # -*- coding: utf-8 -*- # Copyright 2014 - 2016 OpenMarket Ltd # Copyright 2017 Vector Creations Ltd +# Copyright 2019 - 2020 The Matrix.org Foundation C.I.C. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. @@ -25,6 +26,7 @@ from typing import ( Dict, Iterable, List, + Mapping, Optional, Tuple, Union, @@ -181,17 +183,12 @@ class AuthHandler(BaseHandler): # better way to break the loop account_handler = ModuleApi(hs, self) - self.password_providers = [] - for module, config in hs.config.password_providers: - try: - self.password_providers.append( - module(config=config, account_handler=account_handler) - ) - except Exception as e: - logger.error("Error while initializing %r: %s", module, e) - raise + self.password_providers = [ + PasswordProvider.load(module, config, account_handler) + for module, config in hs.config.password_providers + ] - logger.info("Extra password_providers: %r", self.password_providers) + logger.info("Extra password_providers: %s", self.password_providers) self.hs = hs # FIXME better possibility to access registrationHandler later? self.macaroon_gen = hs.get_macaroon_generator() @@ -205,15 +202,23 @@ class AuthHandler(BaseHandler): # type in the list. (NB that the spec doesn't require us to do so and # clients which favour types that they don't understand over those that # they do are technically broken) + + # start out by assuming PASSWORD is enabled; we will remove it later if not. login_types = [] - if self._password_enabled: + if hs.config.password_localdb_enabled: login_types.append(LoginType.PASSWORD) + for provider in self.password_providers: if hasattr(provider, "get_supported_login_types"): for t in provider.get_supported_login_types().keys(): if t not in login_types: login_types.append(t) + + if not self._password_enabled: + login_types.remove(LoginType.PASSWORD) + self._supported_login_types = login_types + # Login types and UI Auth types have a heavy overlap, but are not # necessarily identical. Login types have SSO (and other login types) # added in the rest layer, see synapse.rest.client.v1.login.LoginRestServerlet.on_GET. @@ -230,6 +235,13 @@ class AuthHandler(BaseHandler): burst_count=self.hs.config.rc_login_failed_attempts.burst_count, ) + # Ratelimitier for failed /login attempts + self._failed_login_attempts_ratelimiter = Ratelimiter( + clock=hs.get_clock(), + rate_hz=self.hs.config.rc_login_failed_attempts.per_second, + burst_count=self.hs.config.rc_login_failed_attempts.burst_count, + ) + self._clock = self.hs.get_clock() # Expire old UI auth sessions after a period of time. @@ -642,14 +654,8 @@ class AuthHandler(BaseHandler): res = await checker.check_auth(authdict, clientip=clientip) return res - # build a v1-login-style dict out of the authdict and fall back to the - # v1 code - user_id = authdict.get("user") - - if user_id is None: - raise SynapseError(400, "", Codes.MISSING_PARAM) - - (canonical_id, callback) = await self.validate_login(user_id, authdict) + # fall back to the v1 login flow + canonical_id, _ = await self.validate_login(authdict) return canonical_id def _get_params_recaptcha(self) -> dict: @@ -824,17 +830,17 @@ class AuthHandler(BaseHandler): return self._supported_login_types async def validate_login( - self, username: str, login_submission: Dict[str, Any] + self, login_submission: Dict[str, Any], ratelimit: bool = False, ) -> Tuple[str, Optional[Callable[[Dict[str, str]], None]]]: """Authenticates the user for the /login API - Also used by the user-interactive auth flow to validate - m.login.password auth types. + Also used by the user-interactive auth flow to validate auth types which don't + have an explicit UIA handler, including m.password.auth. Args: - username: username supplied by the user login_submission: the whole of the login submission (including 'type' and other relevant fields) + ratelimit: whether to apply the failed_login_attempt ratelimiter Returns: A tuple of the canonical user id, and optional callback to be called once the access token and device id are issued @@ -843,38 +849,160 @@ class AuthHandler(BaseHandler): SynapseError if there was a problem with the request LoginError if there was an authentication problem. """ - - if username.startswith("@"): - qualified_user_id = username - else: - qualified_user_id = UserID(username, self.hs.hostname).to_string() - login_type = login_submission.get("type") - known_login_type = False + if not isinstance(login_type, str): + raise SynapseError(400, "Bad parameter: type", Codes.INVALID_PARAM) + + # ideally, we wouldn't be checking the identifier unless we know we have a login + # method which uses it (https://github.com/matrix-org/synapse/issues/8836) + # + # But the auth providers' check_auth interface requires a username, so in + # practice we can only support login methods which we can map to a username + # anyway. # special case to check for "password" for the check_password interface # for the auth providers password = login_submission.get("password") - if login_type == LoginType.PASSWORD: if not self._password_enabled: raise SynapseError(400, "Password login has been disabled.") - if not password: - raise SynapseError(400, "Missing parameter: password") + if not isinstance(password, str): + raise SynapseError(400, "Bad parameter: password", Codes.INVALID_PARAM) - for provider in self.password_providers: - if hasattr(provider, "check_password") and login_type == LoginType.PASSWORD: - known_login_type = True - is_valid = await provider.check_password(qualified_user_id, password) - if is_valid: - return qualified_user_id, None + # map old-school login fields into new-school "identifier" fields. + identifier_dict = convert_client_dict_legacy_fields_to_identifier( + login_submission + ) - if not hasattr(provider, "get_supported_login_types") or not hasattr( - provider, "check_auth" - ): - # this password provider doesn't understand custom login types - continue + # convert phone type identifiers to generic threepids + if identifier_dict["type"] == "m.id.phone": + identifier_dict = login_id_phone_to_thirdparty(identifier_dict) + + # convert threepid identifiers to user IDs + if identifier_dict["type"] == "m.id.thirdparty": + address = identifier_dict.get("address") + medium = identifier_dict.get("medium") + + if medium is None or address is None: + raise SynapseError(400, "Invalid thirdparty identifier") + + # For emails, canonicalise the address. + # We store all email addresses canonicalised in the DB. + # (See add_threepid in synapse/handlers/auth.py) + if medium == "email": + try: + address = canonicalise_email(address) + except ValueError as e: + raise SynapseError(400, str(e)) + + # We also apply account rate limiting using the 3PID as a key, as + # otherwise using 3PID bypasses the ratelimiting based on user ID. + if ratelimit: + self._failed_login_attempts_ratelimiter.ratelimit( + (medium, address), update=False + ) + # Check for login providers that support 3pid login types + if login_type == LoginType.PASSWORD: + # we've already checked that there is a (valid) password field + assert isinstance(password, str) + ( + canonical_user_id, + callback_3pid, + ) = await self.check_password_provider_3pid(medium, address, password) + if canonical_user_id: + # Authentication through password provider and 3pid succeeded + return canonical_user_id, callback_3pid + + # No password providers were able to handle this 3pid + # Check local store + user_id = await self.hs.get_datastore().get_user_id_by_threepid( + medium, address + ) + if not user_id: + logger.warning( + "unknown 3pid identifier medium %s, address %r", medium, address + ) + # We mark that we've failed to log in here, as + # `check_password_provider_3pid` might have returned `None` due + # to an incorrect password, rather than the account not + # existing. + # + # If it returned None but the 3PID was bound then we won't hit + # this code path, which is fine as then the per-user ratelimit + # will kick in below. + if ratelimit: + self._failed_login_attempts_ratelimiter.can_do_action( + (medium, address) + ) + raise LoginError(403, "", errcode=Codes.FORBIDDEN) + + identifier_dict = {"type": "m.id.user", "user": user_id} + + # by this point, the identifier should be an m.id.user: if it's anything + # else, we haven't understood it. + if identifier_dict["type"] != "m.id.user": + raise SynapseError(400, "Unknown login identifier type") + + username = identifier_dict.get("user") + if not username: + raise SynapseError(400, "User identifier is missing 'user' key") + + if username.startswith("@"): + qualified_user_id = username + else: + qualified_user_id = UserID(username, self.hs.hostname).to_string() + + # Check if we've hit the failed ratelimit (but don't update it) + if ratelimit: + self._failed_login_attempts_ratelimiter.ratelimit( + qualified_user_id.lower(), update=False + ) + + try: + return await self._validate_userid_login(username, login_submission) + except LoginError: + # The user has failed to log in, so we need to update the rate + # limiter. Using `can_do_action` avoids us raising a ratelimit + # exception and masking the LoginError. The actual ratelimiting + # should have happened above. + if ratelimit: + self._failed_login_attempts_ratelimiter.can_do_action( + qualified_user_id.lower() + ) + raise + + async def _validate_userid_login( + self, username: str, login_submission: Dict[str, Any], + ) -> Tuple[str, Optional[Callable[[Dict[str, str]], None]]]: + """Helper for validate_login + + Handles login, once we've mapped 3pids onto userids + + Args: + username: the username, from the identifier dict + login_submission: the whole of the login submission + (including 'type' and other relevant fields) + Returns: + A tuple of the canonical user id, and optional callback + to be called once the access token and device id are issued + Raises: + StoreError if there was a problem accessing the database + SynapseError if there was a problem with the request + LoginError if there was an authentication problem. + """ + if username.startswith("@"): + qualified_user_id = username + else: + qualified_user_id = UserID(username, self.hs.hostname).to_string() + + login_type = login_submission.get("type") + # we already checked that we have a valid login type + assert isinstance(login_type, str) + + known_login_type = False + + for provider in self.password_providers: supported_login_types = provider.get_supported_login_types() if login_type not in supported_login_types: # this password provider doesn't understand this login type @@ -899,15 +1027,17 @@ class AuthHandler(BaseHandler): result = await provider.check_auth(username, login_type, login_dict) if result: - if isinstance(result, str): - result = (result, None) return result if login_type == LoginType.PASSWORD and self.hs.config.password_localdb_enabled: known_login_type = True + # we've already checked that there is a (valid) password field + password = login_submission["password"] + assert isinstance(password, str) + canonical_user_id = await self._check_local_password( - qualified_user_id, password # type: ignore + qualified_user_id, password ) if canonical_user_id: @@ -938,19 +1068,9 @@ class AuthHandler(BaseHandler): unsuccessful, `user_id` and `callback` are both `None`. """ for provider in self.password_providers: - if hasattr(provider, "check_3pid_auth"): - # This function is able to return a deferred that either - # resolves None, meaning authentication failure, or upon - # success, to a str (which is the user_id) or a tuple of - # (user_id, callback_func), where callback_func should be run - # after we've finished everything else - result = await provider.check_3pid_auth(medium, address, password) - if result: - # Check if the return value is a str or a tuple - if isinstance(result, str): - # If it's a str, set callback function to None - result = (result, None) - return result + result = await provider.check_3pid_auth(medium, address, password) + if result: + return result return None, None @@ -1008,16 +1128,11 @@ class AuthHandler(BaseHandler): # see if any of our auth providers want to know about this for provider in self.password_providers: - if hasattr(provider, "on_logged_out"): - # This might return an awaitable, if it does block the log out - # until it completes. - result = provider.on_logged_out( - user_id=user_info.user_id, - device_id=user_info.device_id, - access_token=access_token, - ) - if inspect.isawaitable(result): - await result + await provider.on_logged_out( + user_id=user_info.user_id, + device_id=user_info.device_id, + access_token=access_token, + ) # delete pushers associated with this access token if user_info.token_id is not None: @@ -1046,11 +1161,10 @@ class AuthHandler(BaseHandler): # see if any of our auth providers want to know about this for provider in self.password_providers: - if hasattr(provider, "on_logged_out"): - for token, token_id, device_id in tokens_and_devices: - await provider.on_logged_out( - user_id=user_id, device_id=device_id, access_token=token - ) + for token, token_id, device_id in tokens_and_devices: + await provider.on_logged_out( + user_id=user_id, device_id=device_id, access_token=token + ) # delete pushers associated with the access tokens await self.hs.get_pusherpool().remove_pushers_by_access_token( @@ -1374,3 +1488,127 @@ class MacaroonGenerator: macaroon.add_first_party_caveat("gen = 1") macaroon.add_first_party_caveat("user_id = %s" % (user_id,)) return macaroon + + +class PasswordProvider: + """Wrapper for a password auth provider module + + This class abstracts out all of the backwards-compatibility hacks for + password providers, to provide a consistent interface. + """ + + @classmethod + def load(cls, module, config, module_api: ModuleApi) -> "PasswordProvider": + try: + pp = module(config=config, account_handler=module_api) + except Exception as e: + logger.error("Error while initializing %r: %s", module, e) + raise + return cls(pp, module_api) + + def __init__(self, pp, module_api: ModuleApi): + self._pp = pp + self._module_api = module_api + + self._supported_login_types = {} + + # grandfather in check_password support + if hasattr(self._pp, "check_password"): + self._supported_login_types[LoginType.PASSWORD] = ("password",) + + g = getattr(self._pp, "get_supported_login_types", None) + if g: + self._supported_login_types.update(g()) + + def __str__(self): + return str(self._pp) + + def get_supported_login_types(self) -> Mapping[str, Iterable[str]]: + """Get the login types supported by this password provider + + Returns a map from a login type identifier (such as m.login.password) to an + iterable giving the fields which must be provided by the user in the submission + to the /login API. + + This wrapper adds m.login.password to the list if the underlying password + provider supports the check_password() api. + """ + return self._supported_login_types + + async def check_auth( + self, username: str, login_type: str, login_dict: JsonDict + ) -> Optional[Tuple[str, Optional[Callable]]]: + """Check if the user has presented valid login credentials + + This wrapper also calls check_password() if the underlying password provider + supports the check_password() api and the login type is m.login.password. + + Args: + username: user id presented by the client. Either an MXID or an unqualified + username. + + login_type: the login type being attempted - one of the types returned by + get_supported_login_types() + + login_dict: the dictionary of login secrets passed by the client. + + Returns: (user_id, callback) where `user_id` is the fully-qualified mxid of the + user, and `callback` is an optional callback which will be called with the + result from the /login call (including access_token, device_id, etc.) + """ + # first grandfather in a call to check_password + if login_type == LoginType.PASSWORD: + g = getattr(self._pp, "check_password", None) + if g: + qualified_user_id = self._module_api.get_qualified_user_id(username) + is_valid = await self._pp.check_password( + qualified_user_id, login_dict["password"] + ) + if is_valid: + return qualified_user_id, None + + g = getattr(self._pp, "check_auth", None) + if not g: + return None + result = await g(username, login_type, login_dict) + + # Check if the return value is a str or a tuple + if isinstance(result, str): + # If it's a str, set callback function to None + return result, None + + return result + + async def check_3pid_auth( + self, medium: str, address: str, password: str + ) -> Optional[Tuple[str, Optional[Callable]]]: + g = getattr(self._pp, "check_3pid_auth", None) + if not g: + return None + + # This function is able to return a deferred that either + # resolves None, meaning authentication failure, or upon + # success, to a str (which is the user_id) or a tuple of + # (user_id, callback_func), where callback_func should be run + # after we've finished everything else + result = await g(medium, address, password) + + # Check if the return value is a str or a tuple + if isinstance(result, str): + # If it's a str, set callback function to None + return result, None + + return result + + async def on_logged_out( + self, user_id: str, device_id: Optional[str], access_token: str + ) -> None: + g = getattr(self._pp, "on_logged_out", None) + if not g: + return + + # This might return an awaitable, if it does block the log out + # until it completes. + result = g(user_id=user_id, device_id=device_id, access_token=access_token,) + if inspect.isawaitable(result): + await result diff --git a/synapse/handlers/identity.py b/synapse/handlers/identity.py
index bc3e9607ca..9b3c6b4551 100644 --- a/synapse/handlers/identity.py +++ b/synapse/handlers/identity.py
@@ -354,7 +354,8 @@ class IdentityHandler(BaseHandler): raise SynapseError(500, "An error was encountered when sending the email") token_expires = ( - self.hs.clock.time_msec() + self.hs.config.email_validation_token_lifetime + self.hs.get_clock().time_msec() + + self.hs.config.email_validation_token_lifetime ) await self.store.start_or_continue_validation_session( diff --git a/synapse/handlers/oidc_handler.py b/synapse/handlers/oidc_handler.py
index 78c4e94a9d..55c4377890 100644 --- a/synapse/handlers/oidc_handler.py +++ b/synapse/handlers/oidc_handler.py
@@ -39,7 +39,7 @@ from synapse.handlers._base import BaseHandler from synapse.handlers.sso import MappingException, UserAttributes from synapse.http.site import SynapseRequest from synapse.logging.context import make_deferred_yieldable -from synapse.types import JsonDict, map_username_to_mxid_localpart +from synapse.types import JsonDict, UserID, map_username_to_mxid_localpart from synapse.util import json_decoder if TYPE_CHECKING: @@ -898,13 +898,39 @@ class OidcHandler(BaseHandler): return UserAttributes(**attributes) + async def grandfather_existing_users() -> Optional[str]: + if self._allow_existing_users: + # If allowing existing users we want to generate a single localpart + # and attempt to match it. + attributes = await oidc_response_to_user_attributes(failures=0) + + user_id = UserID(attributes.localpart, self.server_name).to_string() + users = await self.store.get_users_by_id_case_insensitive(user_id) + if users: + # If an existing matrix ID is returned, then use it. + if len(users) == 1: + previously_registered_user_id = next(iter(users)) + elif user_id in users: + previously_registered_user_id = user_id + else: + # Do not attempt to continue generating Matrix IDs. + raise MappingException( + "Attempted to login as '{}' but it matches more than one user inexactly: {}".format( + user_id, users + ) + ) + + return previously_registered_user_id + + return None + return await self._sso_handler.get_mxid_from_sso( self._auth_provider_id, remote_user_id, user_agent, ip_address, oidc_response_to_user_attributes, - self._allow_existing_users, + grandfather_existing_users, ) diff --git a/synapse/handlers/pagination.py b/synapse/handlers/pagination.py
index 426b58da9e..5372753707 100644 --- a/synapse/handlers/pagination.py +++ b/synapse/handlers/pagination.py
@@ -299,17 +299,22 @@ class PaginationHandler: """ return self._purges_by_id.get(purge_id) - async def purge_room(self, room_id: str) -> None: - """Purge the given room from the database""" + async def purge_room(self, room_id: str, force: bool = False) -> None: + """Purge the given room from the database. + + Args: + room_id: room to be purged + force: set true to skip checking for joined users. + """ with await self.pagination_lock.write(room_id): # check we know about the room await self.store.get_room_version_id(room_id) # first check that we have no users in this room - joined = await self.store.is_host_joined(room_id, self._server_name) - - if joined: - raise SynapseError(400, "Users are still joined to this room") + if not force: + joined = await self.store.is_host_joined(room_id, self._server_name) + if joined: + raise SynapseError(400, "Users are still joined to this room") await self.storage.purge_events.purge_room(room_id) diff --git a/synapse/handlers/room_member.py b/synapse/handlers/room_member.py
index 4e693a419e..4d8ffe8821 100644 --- a/synapse/handlers/room_member.py +++ b/synapse/handlers/room_member.py
@@ -366,7 +366,15 @@ class RoomMemberHandler(metaclass=abc.ABCMeta): # later on. content = dict(content) - if not self.allow_per_room_profiles or requester.shadow_banned: + # allow the server notices mxid to set room-level profile + is_requester_server_notices_user = ( + self._server_notices_mxid is not None + and requester.user.to_string() == self._server_notices_mxid + ) + + if ( + not self.allow_per_room_profiles and not is_requester_server_notices_user + ) or requester.shadow_banned: # Strip profile data, knowing that new profile data will be added to the # event's content in event_creation_handler.create_event() using the target's # global profile. diff --git a/synapse/handlers/saml_handler.py b/synapse/handlers/saml_handler.py
index 34db10ffe4..76d4169fe2 100644 --- a/synapse/handlers/saml_handler.py +++ b/synapse/handlers/saml_handler.py
@@ -265,10 +265,10 @@ class SamlHandler(BaseHandler): return UserAttributes( localpart=result.get("mxid_localpart"), display_name=result.get("displayname"), - emails=result.get("emails"), + emails=result.get("emails", []), ) - with (await self._mapping_lock.queue(self._auth_provider_id)): + async def grandfather_existing_users() -> Optional[str]: # backwards-compatibility hack: see if there is an existing user with a # suitable mapping from the uid if ( @@ -290,17 +290,18 @@ class SamlHandler(BaseHandler): if users: registered_user_id = list(users.keys())[0] logger.info("Grandfathering mapping to %s", registered_user_id) - await self.store.record_user_external_id( - self._auth_provider_id, remote_user_id, registered_user_id - ) return registered_user_id + return None + + with (await self._mapping_lock.queue(self._auth_provider_id)): return await self._sso_handler.get_mxid_from_sso( self._auth_provider_id, remote_user_id, user_agent, ip_address, saml_response_to_remapped_user_attributes, + grandfather_existing_users, ) def expire_sessions(self): diff --git a/synapse/handlers/sso.py b/synapse/handlers/sso.py
index d963082210..f42b90e1bc 100644 --- a/synapse/handlers/sso.py +++ b/synapse/handlers/sso.py
@@ -116,7 +116,7 @@ class SsoHandler(BaseHandler): user_agent: str, ip_address: str, sso_to_matrix_id_mapper: Callable[[int], Awaitable[UserAttributes]], - allow_existing_users: bool = False, + grandfather_existing_users: Optional[Callable[[], Awaitable[Optional[str]]]], ) -> str: """ Given an SSO ID, retrieve the user ID for it and possibly register the user. @@ -125,6 +125,10 @@ class SsoHandler(BaseHandler): if it has that matrix ID is returned regardless of the current mapping logic. + If a callable is provided for grandfathering users, it is called and can + potentially return a matrix ID to use. If it does, the SSO ID is linked to + this matrix ID for subsequent calls. + The mapping function is called (potentially multiple times) to generate a localpart for the user. @@ -132,17 +136,6 @@ class SsoHandler(BaseHandler): given user-agent and IP address and the SSO ID is linked to this matrix ID for subsequent calls. - If allow_existing_users is true the mapping function is only called once - and results in: - - 1. The use of a previously registered matrix ID. In this case, the - SSO ID is linked to the matrix ID. (Note it is possible that - other SSO IDs are linked to the same matrix ID.) - 2. An unused localpart, in which case the user is registered (as - discussed above). - 3. An error if the generated localpart matches multiple pre-existing - matrix IDs. Generally this should not happen. - Args: auth_provider_id: A unique identifier for this SSO provider, e.g. "oidc" or "saml". @@ -152,8 +145,9 @@ class SsoHandler(BaseHandler): sso_to_matrix_id_mapper: A callable to generate the user attributes. The only parameter is an integer which represents the amount of times the returned mxid localpart mapping has failed. - allow_existing_users: True if the localpart returned from the - mapping provider can be linked to an existing matrix ID. + grandfather_existing_users: A callable which can return an previously + existing matrix ID. The SSO ID is then linked to the returned + matrix ID. Returns: The user ID associated with the SSO response. @@ -171,6 +165,16 @@ class SsoHandler(BaseHandler): if previously_registered_user_id: return previously_registered_user_id + # Check for grandfathering of users. + if grandfather_existing_users: + previously_registered_user_id = await grandfather_existing_users() + if previously_registered_user_id: + # Future logins should also match this user ID. + await self.store.record_user_external_id( + auth_provider_id, remote_user_id, previously_registered_user_id + ) + return previously_registered_user_id + # Otherwise, generate a new user. for i in range(self._MAP_USERNAME_RETRIES): try: @@ -194,33 +198,7 @@ class SsoHandler(BaseHandler): # Check if this mxid already exists user_id = UserID(attributes.localpart, self.server_name).to_string() - users = await self.store.get_users_by_id_case_insensitive(user_id) - # Note, if allow_existing_users is true then the loop is guaranteed - # to end on the first iteration: either by matching an existing user, - # raising an error, or registering a new user. See the docstring for - # more in-depth an explanation. - if users and allow_existing_users: - # If an existing matrix ID is returned, then use it. - if len(users) == 1: - previously_registered_user_id = next(iter(users)) - elif user_id in users: - previously_registered_user_id = user_id - else: - # Do not attempt to continue generating Matrix IDs. - raise MappingException( - "Attempted to login as '{}' but it matches more than one user inexactly: {}".format( - user_id, users - ) - ) - - # Future logins should also match this user ID. - await self.store.record_user_external_id( - auth_provider_id, remote_user_id, previously_registered_user_id - ) - - return previously_registered_user_id - - elif not users: + if not await self.store.get_users_by_id_case_insensitive(user_id): # This mxid is free break else: