1063 lines
38 KiB
Python
1063 lines
38 KiB
Python
# Copyright 2020 The Matrix.org Foundation C.I.C.
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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import abc
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import logging
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from typing import (
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TYPE_CHECKING,
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Any,
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Awaitable,
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Callable,
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Collection,
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Dict,
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Iterable,
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List,
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Mapping,
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Optional,
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Set,
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)
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from urllib.parse import urlencode
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import attr
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from typing_extensions import NoReturn, Protocol
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from twisted.web.iweb import IRequest
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from twisted.web.server import Request
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from synapse.api.constants import LoginType
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from synapse.api.errors import Codes, NotFoundError, RedirectException, SynapseError
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from synapse.config.sso import SsoAttributeRequirement
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from synapse.handlers.register import init_counters_for_auth_provider
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from synapse.handlers.ui_auth import UIAuthSessionDataConstants
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from synapse.http import get_request_user_agent
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from synapse.http.server import respond_with_html, respond_with_redirect
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from synapse.http.site import SynapseRequest
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from synapse.types import (
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JsonDict,
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UserID,
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contains_invalid_mxid_characters,
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create_requester,
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)
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from synapse.util.async_helpers import Linearizer
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from synapse.util.stringutils import random_string
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if TYPE_CHECKING:
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from synapse.server import HomeServer
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logger = logging.getLogger(__name__)
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class MappingException(Exception):
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"""Used to catch errors when mapping an SSO response to user attributes.
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Note that the msg that is raised is shown to end-users.
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"""
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class SsoIdentityProvider(Protocol):
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"""Abstract base class to be implemented by SSO Identity Providers
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An Identity Provider, or IdP, is an external HTTP service which authenticates a user
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to say whether they should be allowed to log in, or perform a given action.
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Synapse supports various implementations of IdPs, including OpenID Connect, SAML,
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and CAS.
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The main entry point is `handle_redirect_request`, which should return a URI to
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redirect the user's browser to the IdP's authentication page.
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Each IdP should be registered with the SsoHandler via
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`hs.get_sso_handler().register_identity_provider()`, so that requests to
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`/_matrix/client/r0/login/sso/redirect` can be correctly dispatched.
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"""
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@property
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@abc.abstractmethod
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def idp_id(self) -> str:
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"""A unique identifier for this SSO provider
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Eg, "saml", "cas", "github"
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"""
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@property
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@abc.abstractmethod
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def idp_name(self) -> str:
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"""User-facing name for this provider"""
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@property
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def idp_icon(self) -> Optional[str]:
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"""Optional MXC URI for user-facing icon"""
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return None
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@property
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def idp_brand(self) -> Optional[str]:
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"""Optional branding identifier"""
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return None
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@abc.abstractmethod
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async def handle_redirect_request(
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self,
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request: SynapseRequest,
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client_redirect_url: Optional[bytes],
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ui_auth_session_id: Optional[str] = None,
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) -> str:
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"""Handle an incoming request to /login/sso/redirect
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Args:
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request: the incoming HTTP request
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client_redirect_url: the URL that we should redirect the
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client to after login (or None for UI Auth).
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ui_auth_session_id: The session ID of the ongoing UI Auth (or
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None if this is a login).
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Returns:
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URL to redirect to
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"""
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raise NotImplementedError()
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@attr.s(auto_attribs=True)
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class UserAttributes:
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# NB: This struct is documented in docs/sso_mapping_providers.md so that users can
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# populate it with data from their own mapping providers.
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# the localpart of the mxid that the mapper has assigned to the user.
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# if `None`, the mapper has not picked a userid, and the user should be prompted to
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# enter one.
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localpart: Optional[str]
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confirm_localpart: bool = False
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display_name: Optional[str] = None
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emails: Collection[str] = attr.Factory(list)
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@attr.s(slots=True, auto_attribs=True)
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class UsernameMappingSession:
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"""Data we track about SSO sessions"""
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# A unique identifier for this SSO provider, e.g. "oidc" or "saml".
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auth_provider_id: str
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# user ID on the IdP server
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remote_user_id: str
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# attributes returned by the ID mapper
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display_name: Optional[str]
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emails: Collection[str]
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# An optional dictionary of extra attributes to be provided to the client in the
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# login response.
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extra_login_attributes: Optional[JsonDict]
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# where to redirect the client back to
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client_redirect_url: str
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# expiry time for the session, in milliseconds
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expiry_time_ms: int
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# choices made by the user
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chosen_localpart: Optional[str] = None
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use_display_name: bool = True
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emails_to_use: Collection[str] = ()
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terms_accepted_version: Optional[str] = None
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# the HTTP cookie used to track the mapping session id
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USERNAME_MAPPING_SESSION_COOKIE_NAME = b"username_mapping_session"
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class SsoHandler:
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# The number of attempts to ask the mapping provider for when generating an MXID.
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_MAP_USERNAME_RETRIES = 1000
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# the time a UsernameMappingSession remains valid for
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_MAPPING_SESSION_VALIDITY_PERIOD_MS = 15 * 60 * 1000
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def __init__(self, hs: "HomeServer"):
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self._clock = hs.get_clock()
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self._store = hs.get_datastores().main
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self._server_name = hs.hostname
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self._registration_handler = hs.get_registration_handler()
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self._auth_handler = hs.get_auth_handler()
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self._error_template = hs.config.sso.sso_error_template
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self._bad_user_template = hs.config.sso.sso_auth_bad_user_template
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self._profile_handler = hs.get_profile_handler()
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# The following template is shown after a successful user interactive
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# authentication session. It tells the user they can close the window.
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self._sso_auth_success_template = hs.config.sso.sso_auth_success_template
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self._sso_update_profile_information = (
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hs.config.sso.sso_update_profile_information
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)
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# a lock on the mappings
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self._mapping_lock = Linearizer(name="sso_user_mapping", clock=hs.get_clock())
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# a map from session id to session data
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self._username_mapping_sessions: Dict[str, UsernameMappingSession] = {}
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# map from idp_id to SsoIdentityProvider
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self._identity_providers: Dict[str, SsoIdentityProvider] = {}
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self._consent_at_registration = hs.config.consent.user_consent_at_registration
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def register_identity_provider(self, p: SsoIdentityProvider) -> None:
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p_id = p.idp_id
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assert p_id not in self._identity_providers
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self._identity_providers[p_id] = p
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init_counters_for_auth_provider(p_id)
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def get_identity_providers(self) -> Mapping[str, SsoIdentityProvider]:
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"""Get the configured identity providers"""
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return self._identity_providers
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async def get_identity_providers_for_user(
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self, user_id: str
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) -> Mapping[str, SsoIdentityProvider]:
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"""Get the SsoIdentityProviders which a user has used
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Given a user id, get the identity providers that that user has used to log in
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with in the past (and thus could use to re-identify themselves for UI Auth).
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Args:
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user_id: MXID of user to look up
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Raises:
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a map of idp_id to SsoIdentityProvider
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"""
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external_ids = await self._store.get_external_ids_by_user(user_id)
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valid_idps = {}
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for idp_id, _ in external_ids:
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idp = self._identity_providers.get(idp_id)
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if not idp:
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logger.warning(
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"User %r has an SSO mapping for IdP %r, but this is no longer "
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"configured.",
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user_id,
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idp_id,
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)
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else:
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valid_idps[idp_id] = idp
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return valid_idps
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def render_error(
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self,
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request: Request,
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error: str,
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error_description: Optional[str] = None,
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code: int = 400,
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) -> None:
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"""Renders the error template and responds with it.
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This is used to show errors to the user. The template of this page can
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be found under `synapse/res/templates/sso_error.html`.
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Args:
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request: The incoming request from the browser.
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We'll respond with an HTML page describing the error.
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error: A technical identifier for this error.
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error_description: A human-readable description of the error.
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code: The integer error code (an HTTP response code)
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"""
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html = self._error_template.render(
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error=error, error_description=error_description
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)
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respond_with_html(request, code, html)
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async def handle_redirect_request(
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self,
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request: SynapseRequest,
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client_redirect_url: bytes,
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idp_id: Optional[str],
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) -> str:
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"""Handle a request to /login/sso/redirect
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Args:
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request: incoming HTTP request
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client_redirect_url: the URL that we should redirect the
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client to after login.
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idp_id: optional identity provider chosen by the client
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Returns:
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the URI to redirect to
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"""
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if not self._identity_providers:
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raise SynapseError(
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400, "Homeserver not configured for SSO.", errcode=Codes.UNRECOGNIZED
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)
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# if the client chose an IdP, use that
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idp: Optional[SsoIdentityProvider] = None
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if idp_id:
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idp = self._identity_providers.get(idp_id)
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if not idp:
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raise NotFoundError("Unknown identity provider")
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# if we only have one auth provider, redirect to it directly
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elif len(self._identity_providers) == 1:
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idp = next(iter(self._identity_providers.values()))
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if idp:
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return await idp.handle_redirect_request(request, client_redirect_url)
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# otherwise, redirect to the IDP picker
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return "/_synapse/client/pick_idp?" + urlencode(
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(("redirectUrl", client_redirect_url),)
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)
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async def get_sso_user_by_remote_user_id(
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self, auth_provider_id: str, remote_user_id: str
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) -> Optional[str]:
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"""
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Maps the user ID of a remote IdP to a mxid for a previously seen user.
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If the user has not been seen yet, this will return None.
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Args:
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auth_provider_id: A unique identifier for this SSO provider, e.g.
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"oidc" or "saml".
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remote_user_id: The user ID according to the remote IdP. This might
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be an e-mail address, a GUID, or some other form. It must be
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unique and immutable.
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Returns:
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The mxid of a previously seen user.
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"""
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logger.debug(
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"Looking for existing mapping for user %s:%s",
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auth_provider_id,
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remote_user_id,
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)
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# Check if we already have a mapping for this user.
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previously_registered_user_id = await self._store.get_user_by_external_id(
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auth_provider_id,
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remote_user_id,
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)
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# A match was found, return the user ID.
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if previously_registered_user_id is not None:
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logger.info(
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"Found existing mapping for IdP '%s' and remote_user_id '%s': %s",
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auth_provider_id,
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remote_user_id,
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previously_registered_user_id,
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)
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return previously_registered_user_id
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# No match.
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return None
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async def complete_sso_login_request(
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self,
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auth_provider_id: str,
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remote_user_id: str,
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request: SynapseRequest,
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client_redirect_url: str,
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sso_to_matrix_id_mapper: Callable[[int], Awaitable[UserAttributes]],
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grandfather_existing_users: Callable[[], Awaitable[Optional[str]]],
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extra_login_attributes: Optional[JsonDict] = None,
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auth_provider_session_id: Optional[str] = None,
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) -> None:
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"""
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Given an SSO ID, retrieve the user ID for it and possibly register the user.
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This first checks if the SSO ID has previously been linked to a matrix ID,
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if it has that matrix ID is returned regardless of the current mapping
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logic.
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If a callable is provided for grandfathering users, it is called and can
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potentially return a matrix ID to use. If it does, the SSO ID is linked to
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this matrix ID for subsequent calls.
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The mapping function is called (potentially multiple times) to generate
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a localpart for the user.
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If an unused localpart is generated, the user is registered from the
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given user-agent and IP address and the SSO ID is linked to this matrix
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ID for subsequent calls.
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Finally, we generate a redirect to the supplied redirect uri, with a login token
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Args:
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auth_provider_id: A unique identifier for this SSO provider, e.g.
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"oidc" or "saml".
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remote_user_id: The unique identifier from the SSO provider.
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request: The request to respond to
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client_redirect_url: The redirect URL passed in by the client.
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sso_to_matrix_id_mapper: A callable to generate the user attributes.
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The only parameter is an integer which represents the amount of
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times the returned mxid localpart mapping has failed.
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It is expected that the mapper can raise two exceptions, which
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will get passed through to the caller:
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MappingException if there was a problem mapping the response
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to the user.
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RedirectException to redirect to an additional page (e.g.
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to prompt the user for more information).
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grandfather_existing_users: A callable which can return an previously
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existing matrix ID. The SSO ID is then linked to the returned
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matrix ID.
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extra_login_attributes: An optional dictionary of extra
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attributes to be provided to the client in the login response.
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auth_provider_session_id: An optional session ID from the IdP.
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Raises:
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MappingException if there was a problem mapping the response to a user.
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RedirectException: if the mapping provider needs to redirect the user
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to an additional page. (e.g. to prompt for more information)
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"""
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new_user = False
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# grab a lock while we try to find a mapping for this user. This seems...
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# optimistic, especially for implementations that end up redirecting to
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# interstitial pages.
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async with self._mapping_lock.queue(auth_provider_id):
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# first of all, check if we already have a mapping for this user
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user_id = await self.get_sso_user_by_remote_user_id(
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auth_provider_id,
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remote_user_id,
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)
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# Check for grandfathering of users.
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if not user_id:
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user_id = await grandfather_existing_users()
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if user_id:
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# Future logins should also match this user ID.
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await self._store.record_user_external_id(
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auth_provider_id, remote_user_id, user_id
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)
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# Otherwise, generate a new user.
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if not user_id:
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attributes = await self._call_attribute_mapper(sso_to_matrix_id_mapper)
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next_step_url = self._get_url_for_next_new_user_step(
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attributes=attributes
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)
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if next_step_url:
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await self._redirect_to_next_new_user_step(
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auth_provider_id,
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remote_user_id,
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attributes,
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client_redirect_url,
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next_step_url,
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extra_login_attributes,
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)
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user_id = await self._register_mapped_user(
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attributes,
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auth_provider_id,
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remote_user_id,
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get_request_user_agent(request),
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request.getClientAddress().host,
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)
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new_user = True
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elif self._sso_update_profile_information:
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attributes = await self._call_attribute_mapper(sso_to_matrix_id_mapper)
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if attributes.display_name:
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user_id_obj = UserID.from_string(user_id)
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profile_display_name = await self._profile_handler.get_displayname(
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user_id_obj
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)
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if profile_display_name != attributes.display_name:
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requester = create_requester(
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user_id,
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authenticated_entity=user_id,
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)
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await self._profile_handler.set_displayname(
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user_id_obj, requester, attributes.display_name, True
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)
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await self._auth_handler.complete_sso_login(
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user_id,
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auth_provider_id,
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request,
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client_redirect_url,
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extra_login_attributes,
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new_user=new_user,
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auth_provider_session_id=auth_provider_session_id,
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)
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async def _call_attribute_mapper(
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self,
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sso_to_matrix_id_mapper: Callable[[int], Awaitable[UserAttributes]],
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) -> UserAttributes:
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"""Call the attribute mapper function in a loop, until we get a unique userid"""
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for i in range(self._MAP_USERNAME_RETRIES):
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try:
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attributes = await sso_to_matrix_id_mapper(i)
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except (RedirectException, MappingException):
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# Mapping providers are allowed to issue a redirect (e.g. to ask
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# the user for more information) and can issue a mapping exception
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# if a name cannot be generated.
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raise
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except Exception as e:
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# Any other exception is unexpected.
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raise MappingException(
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"Could not extract user attributes from SSO response."
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) from e
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logger.debug(
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"Retrieved user attributes from user mapping provider: %r (attempt %d)",
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attributes,
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i,
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)
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if not attributes.localpart:
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# the mapper has not picked a localpart
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return attributes
|
|
|
|
# Check if this mxid already exists
|
|
user_id = UserID(attributes.localpart, self._server_name).to_string()
|
|
if not await self._store.get_users_by_id_case_insensitive(user_id):
|
|
# This mxid is free
|
|
break
|
|
else:
|
|
# Unable to generate a username in 1000 iterations
|
|
# Break and return error to the user
|
|
raise MappingException(
|
|
"Unable to generate a Matrix ID from the SSO response"
|
|
)
|
|
return attributes
|
|
|
|
def _get_url_for_next_new_user_step(
|
|
self,
|
|
attributes: Optional[UserAttributes] = None,
|
|
session: Optional[UsernameMappingSession] = None,
|
|
) -> bytes:
|
|
"""Returns the URL to redirect to for the next step of new user registration
|
|
|
|
Given attributes from the user mapping provider or a UsernameMappingSession,
|
|
returns the URL to redirect to for the next step of the registration flow.
|
|
|
|
Args:
|
|
attributes: the user attributes returned by the user mapping provider,
|
|
from before a UsernameMappingSession has begun.
|
|
|
|
session: an active UsernameMappingSession, possibly with some of its
|
|
attributes chosen by the user.
|
|
|
|
Returns:
|
|
The URL to redirect to, or an empty value if no redirect is necessary
|
|
"""
|
|
# Must provide either attributes or session, not both
|
|
assert (attributes is not None) != (session is not None)
|
|
|
|
if (
|
|
attributes
|
|
and (attributes.localpart is None or attributes.confirm_localpart is True)
|
|
) or (session and session.chosen_localpart is None):
|
|
return b"/_synapse/client/pick_username/account_details"
|
|
elif self._consent_at_registration and not (
|
|
session and session.terms_accepted_version
|
|
):
|
|
return b"/_synapse/client/new_user_consent"
|
|
else:
|
|
return b"/_synapse/client/sso_register" if session else b""
|
|
|
|
async def _redirect_to_next_new_user_step(
|
|
self,
|
|
auth_provider_id: str,
|
|
remote_user_id: str,
|
|
attributes: UserAttributes,
|
|
client_redirect_url: str,
|
|
next_step_url: bytes,
|
|
extra_login_attributes: Optional[JsonDict],
|
|
) -> NoReturn:
|
|
"""Creates a UsernameMappingSession and redirects the browser
|
|
|
|
Called if the user mapping provider doesn't return complete information for a new user.
|
|
Raises a RedirectException which redirects the browser to a specified URL.
|
|
|
|
Args:
|
|
auth_provider_id: A unique identifier for this SSO provider, e.g.
|
|
"oidc" or "saml".
|
|
|
|
remote_user_id: The unique identifier from the SSO provider.
|
|
|
|
attributes: the user attributes returned by the user mapping provider.
|
|
|
|
client_redirect_url: The redirect URL passed in by the client, which we
|
|
will eventually redirect back to.
|
|
|
|
next_step_url: The URL to redirect to for the next step of the new user flow.
|
|
|
|
extra_login_attributes: An optional dictionary of extra
|
|
attributes to be provided to the client in the login response.
|
|
|
|
Raises:
|
|
RedirectException
|
|
"""
|
|
# TODO: If needed, allow using/looking up an existing session here.
|
|
session_id = random_string(16)
|
|
now = self._clock.time_msec()
|
|
session = UsernameMappingSession(
|
|
auth_provider_id=auth_provider_id,
|
|
remote_user_id=remote_user_id,
|
|
display_name=attributes.display_name,
|
|
emails=attributes.emails,
|
|
client_redirect_url=client_redirect_url,
|
|
expiry_time_ms=now + self._MAPPING_SESSION_VALIDITY_PERIOD_MS,
|
|
extra_login_attributes=extra_login_attributes,
|
|
# Treat the localpart returned by the user mapping provider as though
|
|
# it was chosen by the user. If it's None, it must be chosen eventually.
|
|
chosen_localpart=attributes.localpart,
|
|
# TODO: Consider letting the user mapping provider specify defaults for
|
|
# other user-chosen attributes.
|
|
)
|
|
|
|
self._username_mapping_sessions[session_id] = session
|
|
logger.info("Recorded registration session id %s", session_id)
|
|
|
|
# Set the cookie and redirect to the next step
|
|
e = RedirectException(next_step_url)
|
|
e.cookies.append(
|
|
b"%s=%s; path=/"
|
|
% (USERNAME_MAPPING_SESSION_COOKIE_NAME, session_id.encode("ascii"))
|
|
)
|
|
raise e
|
|
|
|
async def _register_mapped_user(
|
|
self,
|
|
attributes: UserAttributes,
|
|
auth_provider_id: str,
|
|
remote_user_id: str,
|
|
user_agent: str,
|
|
ip_address: str,
|
|
) -> str:
|
|
"""Register a new SSO user.
|
|
|
|
This is called once we have successfully mapped the remote user id onto a local
|
|
user id, one way or another.
|
|
|
|
Args:
|
|
attributes: user attributes returned by the user mapping provider,
|
|
including a non-empty localpart.
|
|
|
|
auth_provider_id: A unique identifier for this SSO provider, e.g.
|
|
"oidc" or "saml".
|
|
|
|
remote_user_id: The unique identifier from the SSO provider.
|
|
|
|
user_agent: The user-agent in the HTTP request (used for potential
|
|
shadow-banning.)
|
|
|
|
ip_address: The IP address of the requester (used for potential
|
|
shadow-banning.)
|
|
|
|
Raises:
|
|
a MappingException if the localpart is invalid.
|
|
|
|
a SynapseError with code 400 and errcode Codes.USER_IN_USE if the localpart
|
|
is already taken.
|
|
"""
|
|
|
|
# Since the localpart is provided via a potentially untrusted module,
|
|
# ensure the MXID is valid before registering.
|
|
if not attributes.localpart or contains_invalid_mxid_characters(
|
|
attributes.localpart
|
|
):
|
|
raise MappingException("localpart is invalid: %s" % (attributes.localpart,))
|
|
|
|
logger.debug("Mapped SSO user to local part %s", attributes.localpart)
|
|
registered_user_id = await self._registration_handler.register_user(
|
|
localpart=attributes.localpart,
|
|
default_display_name=attributes.display_name,
|
|
bind_emails=attributes.emails,
|
|
user_agent_ips=[(user_agent, ip_address)],
|
|
auth_provider_id=auth_provider_id,
|
|
)
|
|
|
|
await self._store.record_user_external_id(
|
|
auth_provider_id, remote_user_id, registered_user_id
|
|
)
|
|
return registered_user_id
|
|
|
|
async def complete_sso_ui_auth_request(
|
|
self,
|
|
auth_provider_id: str,
|
|
remote_user_id: str,
|
|
ui_auth_session_id: str,
|
|
request: Request,
|
|
) -> None:
|
|
"""
|
|
Given an SSO ID, retrieve the user ID for it and complete UIA.
|
|
|
|
Note that this requires that the user is mapped in the "user_external_ids"
|
|
table. This will be the case if they have ever logged in via SAML or OIDC in
|
|
recentish synapse versions, but may not be for older users.
|
|
|
|
Args:
|
|
auth_provider_id: A unique identifier for this SSO provider, e.g.
|
|
"oidc" or "saml".
|
|
remote_user_id: The unique identifier from the SSO provider.
|
|
ui_auth_session_id: The ID of the user-interactive auth session.
|
|
request: The request to complete.
|
|
"""
|
|
|
|
user_id = await self.get_sso_user_by_remote_user_id(
|
|
auth_provider_id,
|
|
remote_user_id,
|
|
)
|
|
|
|
user_id_to_verify: str = await self._auth_handler.get_session_data(
|
|
ui_auth_session_id, UIAuthSessionDataConstants.REQUEST_USER_ID
|
|
)
|
|
|
|
if not user_id:
|
|
logger.warning(
|
|
"Remote user %s/%s has not previously logged in here: UIA will fail",
|
|
auth_provider_id,
|
|
remote_user_id,
|
|
)
|
|
elif user_id != user_id_to_verify:
|
|
logger.warning(
|
|
"Remote user %s/%s mapped onto incorrect user %s: UIA will fail",
|
|
auth_provider_id,
|
|
remote_user_id,
|
|
user_id,
|
|
)
|
|
else:
|
|
# success!
|
|
# Mark the stage of the authentication as successful.
|
|
await self._store.mark_ui_auth_stage_complete(
|
|
ui_auth_session_id, LoginType.SSO, user_id
|
|
)
|
|
|
|
# Render the HTML confirmation page and return.
|
|
html = self._sso_auth_success_template
|
|
respond_with_html(request, 200, html)
|
|
return
|
|
|
|
# the user_id didn't match: mark the stage of the authentication as unsuccessful
|
|
await self._store.mark_ui_auth_stage_complete(
|
|
ui_auth_session_id, LoginType.SSO, ""
|
|
)
|
|
|
|
# render an error page.
|
|
html = self._bad_user_template.render(
|
|
server_name=self._server_name,
|
|
user_id_to_verify=user_id_to_verify,
|
|
)
|
|
respond_with_html(request, 200, html)
|
|
|
|
def get_mapping_session(self, session_id: str) -> UsernameMappingSession:
|
|
"""Look up the given username mapping session
|
|
|
|
If it is not found, raises a SynapseError with an http code of 400
|
|
|
|
Args:
|
|
session_id: session to look up
|
|
Returns:
|
|
active mapping session
|
|
Raises:
|
|
SynapseError if the session is not found/has expired
|
|
"""
|
|
self._expire_old_sessions()
|
|
session = self._username_mapping_sessions.get(session_id)
|
|
if session:
|
|
return session
|
|
logger.info("Couldn't find session id %s", session_id)
|
|
raise SynapseError(400, "unknown session")
|
|
|
|
async def check_username_availability(
|
|
self,
|
|
localpart: str,
|
|
session_id: str,
|
|
) -> bool:
|
|
"""Handle an "is username available" callback check
|
|
|
|
Args:
|
|
localpart: desired localpart
|
|
session_id: the session id for the username picker
|
|
Returns:
|
|
True if the username is available
|
|
Raises:
|
|
SynapseError if the localpart is invalid or the session is unknown
|
|
"""
|
|
|
|
# make sure that there is a valid mapping session, to stop people dictionary-
|
|
# scanning for accounts
|
|
self.get_mapping_session(session_id)
|
|
|
|
logger.info(
|
|
"[session %s] Checking for availability of username %s",
|
|
session_id,
|
|
localpart,
|
|
)
|
|
|
|
if contains_invalid_mxid_characters(localpart):
|
|
raise SynapseError(400, "localpart is invalid: %s" % (localpart,))
|
|
user_id = UserID(localpart, self._server_name).to_string()
|
|
user_infos = await self._store.get_users_by_id_case_insensitive(user_id)
|
|
|
|
logger.info("[session %s] users: %s", session_id, user_infos)
|
|
return not user_infos
|
|
|
|
async def handle_submit_username_request(
|
|
self,
|
|
request: SynapseRequest,
|
|
session_id: str,
|
|
localpart: str,
|
|
use_display_name: bool,
|
|
emails_to_use: Iterable[str],
|
|
) -> None:
|
|
"""Handle a request to the username-picker 'submit' endpoint
|
|
|
|
Will serve an HTTP response to the request.
|
|
|
|
Args:
|
|
request: HTTP request
|
|
localpart: localpart requested by the user
|
|
session_id: ID of the username mapping session, extracted from a cookie
|
|
use_display_name: whether the user wants to use the suggested display name
|
|
emails_to_use: emails that the user would like to use
|
|
"""
|
|
try:
|
|
session = self.get_mapping_session(session_id)
|
|
except SynapseError as e:
|
|
self.render_error(request, "bad_session", e.msg, code=e.code)
|
|
return
|
|
|
|
# update the session with the user's choices
|
|
session.chosen_localpart = localpart
|
|
session.use_display_name = use_display_name
|
|
|
|
emails_from_idp = set(session.emails)
|
|
filtered_emails: Set[str] = set()
|
|
|
|
# we iterate through the list rather than just building a set conjunction, so
|
|
# that we can log attempts to use unknown addresses
|
|
for email in emails_to_use:
|
|
if email in emails_from_idp:
|
|
filtered_emails.add(email)
|
|
else:
|
|
logger.warning(
|
|
"[session %s] ignoring user request to use unknown email address %r",
|
|
session_id,
|
|
email,
|
|
)
|
|
session.emails_to_use = filtered_emails
|
|
|
|
respond_with_redirect(
|
|
request, self._get_url_for_next_new_user_step(session=session)
|
|
)
|
|
|
|
async def handle_terms_accepted(
|
|
self, request: Request, session_id: str, terms_version: str
|
|
) -> None:
|
|
"""Handle a request to the new-user 'consent' endpoint
|
|
|
|
Will serve an HTTP response to the request.
|
|
|
|
Args:
|
|
request: HTTP request
|
|
session_id: ID of the username mapping session, extracted from a cookie
|
|
terms_version: the version of the terms which the user viewed and consented
|
|
to
|
|
"""
|
|
logger.info(
|
|
"[session %s] User consented to terms version %s",
|
|
session_id,
|
|
terms_version,
|
|
)
|
|
try:
|
|
session = self.get_mapping_session(session_id)
|
|
except SynapseError as e:
|
|
self.render_error(request, "bad_session", e.msg, code=e.code)
|
|
return
|
|
|
|
session.terms_accepted_version = terms_version
|
|
|
|
respond_with_redirect(
|
|
request, self._get_url_for_next_new_user_step(session=session)
|
|
)
|
|
|
|
async def register_sso_user(self, request: Request, session_id: str) -> None:
|
|
"""Called once we have all the info we need to register a new user.
|
|
|
|
Does so and serves an HTTP response
|
|
|
|
Args:
|
|
request: HTTP request
|
|
session_id: ID of the username mapping session, extracted from a cookie
|
|
"""
|
|
try:
|
|
session = self.get_mapping_session(session_id)
|
|
except SynapseError as e:
|
|
self.render_error(request, "bad_session", e.msg, code=e.code)
|
|
return
|
|
|
|
logger.info(
|
|
"[session %s] Registering localpart %s",
|
|
session_id,
|
|
session.chosen_localpart,
|
|
)
|
|
|
|
attributes = UserAttributes(
|
|
localpart=session.chosen_localpart,
|
|
emails=session.emails_to_use,
|
|
)
|
|
|
|
if session.use_display_name:
|
|
attributes.display_name = session.display_name
|
|
|
|
# the following will raise a 400 error if the username has been taken in the
|
|
# meantime.
|
|
user_id = await self._register_mapped_user(
|
|
attributes,
|
|
session.auth_provider_id,
|
|
session.remote_user_id,
|
|
get_request_user_agent(request),
|
|
request.getClientAddress().host,
|
|
)
|
|
|
|
logger.info(
|
|
"[session %s] Registered userid %s with attributes %s",
|
|
session_id,
|
|
user_id,
|
|
attributes,
|
|
)
|
|
|
|
# delete the mapping session and the cookie
|
|
del self._username_mapping_sessions[session_id]
|
|
|
|
# delete the cookie
|
|
request.addCookie(
|
|
USERNAME_MAPPING_SESSION_COOKIE_NAME,
|
|
b"",
|
|
expires=b"Thu, 01 Jan 1970 00:00:00 GMT",
|
|
path=b"/",
|
|
)
|
|
|
|
auth_result = {}
|
|
if session.terms_accepted_version:
|
|
# TODO: make this less awful.
|
|
auth_result[LoginType.TERMS] = True
|
|
|
|
await self._registration_handler.post_registration_actions(
|
|
user_id, auth_result, access_token=None
|
|
)
|
|
|
|
await self._auth_handler.complete_sso_login(
|
|
user_id,
|
|
session.auth_provider_id,
|
|
request,
|
|
session.client_redirect_url,
|
|
session.extra_login_attributes,
|
|
new_user=True,
|
|
)
|
|
|
|
def _expire_old_sessions(self) -> None:
|
|
to_expire = []
|
|
now = int(self._clock.time_msec())
|
|
|
|
for session_id, session in self._username_mapping_sessions.items():
|
|
if session.expiry_time_ms <= now:
|
|
to_expire.append(session_id)
|
|
|
|
for session_id in to_expire:
|
|
logger.info("Expiring mapping session %s", session_id)
|
|
del self._username_mapping_sessions[session_id]
|
|
|
|
def check_required_attributes(
|
|
self,
|
|
request: SynapseRequest,
|
|
attributes: Mapping[str, List[Any]],
|
|
attribute_requirements: Iterable[SsoAttributeRequirement],
|
|
) -> bool:
|
|
"""
|
|
Confirm that the required attributes were present in the SSO response.
|
|
|
|
If all requirements are met, this will return True.
|
|
|
|
If any requirement is not met, then the request will be finalized by
|
|
showing an error page to the user and False will be returned.
|
|
|
|
Args:
|
|
request: The request to (potentially) respond to.
|
|
attributes: The attributes from the SSO IdP.
|
|
attribute_requirements: The requirements that attributes must meet.
|
|
|
|
Returns:
|
|
True if all requirements are met, False if any attribute fails to
|
|
meet the requirement.
|
|
|
|
"""
|
|
# Ensure that the attributes of the logged in user meet the required
|
|
# attributes.
|
|
for requirement in attribute_requirements:
|
|
if not _check_attribute_requirement(attributes, requirement):
|
|
self.render_error(
|
|
request, "unauthorised", "You are not authorised to log in here."
|
|
)
|
|
return False
|
|
|
|
return True
|
|
|
|
|
|
def get_username_mapping_session_cookie_from_request(request: IRequest) -> str:
|
|
"""Extract the session ID from the cookie
|
|
|
|
Raises a SynapseError if the cookie isn't found
|
|
"""
|
|
session_id = request.getCookie(USERNAME_MAPPING_SESSION_COOKIE_NAME)
|
|
if not session_id:
|
|
raise SynapseError(code=400, msg="missing session_id")
|
|
return session_id.decode("ascii", errors="replace")
|
|
|
|
|
|
def _check_attribute_requirement(
|
|
attributes: Mapping[str, List[Any]], req: SsoAttributeRequirement
|
|
) -> bool:
|
|
"""Check if SSO attributes meet the proper requirements.
|
|
|
|
Args:
|
|
attributes: A mapping of attributes to an iterable of one or more values.
|
|
requirement: The configured requirement to check.
|
|
|
|
Returns:
|
|
True if the required attribute was found and had a proper value.
|
|
"""
|
|
if req.attribute not in attributes:
|
|
logger.info("SSO attribute missing: %s", req.attribute)
|
|
return False
|
|
|
|
# If the requirement is None, the attribute existing is enough.
|
|
if req.value is None:
|
|
return True
|
|
|
|
values = attributes[req.attribute]
|
|
if req.value in values:
|
|
return True
|
|
|
|
logger.info(
|
|
"SSO attribute %s did not match required value '%s' (was '%s')",
|
|
req.attribute,
|
|
req.value,
|
|
values,
|
|
)
|
|
return False
|