From 5310808d3bebd17275355ecd474bc013e8c7462d Mon Sep 17 00:00:00 2001 From: Richard van der Hoff Date: Tue, 12 Jan 2021 18:19:42 +0000 Subject: Give the user a better error when they present bad SSO creds If a user tries to do UI Auth via SSO, but uses the wrong account on the SSO IdP, try to give them a better error. Previously, the UIA would claim to be successful, but then the operation in question would simply fail with "auth fail". Instead, serve up an error page which explains the failure. --- synapse/handlers/sso.py | 33 ++++++++++++++++++++++++++++----- 1 file changed, 28 insertions(+), 5 deletions(-) (limited to 'synapse/handlers') diff --git a/synapse/handlers/sso.py b/synapse/handlers/sso.py index d096e0b091..69ffc9d9c2 100644 --- a/synapse/handlers/sso.py +++ b/synapse/handlers/sso.py @@ -23,6 +23,7 @@ from typing_extensions import NoReturn, Protocol from twisted.web.http import Request from synapse.api.errors import Codes, RedirectException, SynapseError +from synapse.handlers.ui_auth import UIAuthSessionDataConstants from synapse.http import get_request_user_agent from synapse.http.server import respond_with_html from synapse.http.site import SynapseRequest @@ -147,6 +148,7 @@ class SsoHandler: self._server_name = hs.hostname self._registration_handler = hs.get_registration_handler() self._error_template = hs.config.sso_error_template + self._bad_user_template = hs.config.sso_auth_bad_user_template self._auth_handler = hs.get_auth_handler() # a lock on the mappings @@ -577,19 +579,40 @@ class SsoHandler: auth_provider_id, remote_user_id, ) + user_id_to_verify = await self._auth_handler.get_session_data( + ui_auth_session_id, UIAuthSessionDataConstants.REQUEST_USER_ID + ) # type: str + 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, ) - # Let the UIA flow handle this the same as if they presented creds for a - # different user. - 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! + await self._auth_handler.complete_sso_ui_auth( + user_id, ui_auth_session_id, request + ) + 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, "" + ) - await self._auth_handler.complete_sso_ui_auth( - user_id, ui_auth_session_id, request + # 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) async def check_username_availability( self, localpart: str, session_id: str, -- cgit 1.5.1 From 420031906a04f7b5462347bf47730d4bc6cc8870 Mon Sep 17 00:00:00 2001 From: Richard van der Hoff Date: Wed, 13 Jan 2021 11:12:28 +0000 Subject: Move `complete_sso_ui_auth` into SSOHandler since we're hacking on this code anyway, may as well move it out of the cluttered AuthHandler. --- synapse/handlers/auth.py | 25 ------------------------- synapse/handlers/sso.py | 16 +++++++++++++--- 2 files changed, 13 insertions(+), 28 deletions(-) (limited to 'synapse/handlers') diff --git a/synapse/handlers/auth.py b/synapse/handlers/auth.py index 4f881a439a..18cd2b62f0 100644 --- a/synapse/handlers/auth.py +++ b/synapse/handlers/auth.py @@ -263,10 +263,6 @@ class AuthHandler(BaseHandler): # authenticating for an operation to occur on their account. self._sso_auth_confirm_template = hs.config.sso_auth_confirm_template - # The following template is shown after a successful user interactive - # authentication session. It tells the user they can close the window. - self._sso_auth_success_template = hs.config.sso_auth_success_template - # The following template is shown during the SSO authentication process if # the account is deactivated. self._sso_account_deactivated_template = ( @@ -1394,27 +1390,6 @@ class AuthHandler(BaseHandler): description=session.description, redirect_url=redirect_url, ) - async def complete_sso_ui_auth( - self, registered_user_id: str, session_id: str, request: Request, - ): - """Having figured out a mxid for this user, complete the HTTP request - - Args: - registered_user_id: The registered user ID to complete SSO login for. - session_id: The ID of the user-interactive auth session. - request: The request to complete. - """ - # Mark the stage of the authentication as successful. - # Save the user who authenticated with SSO, this will be used to ensure - # that the account be modified is also the person who logged in. - await self.store.mark_ui_auth_stage_complete( - session_id, LoginType.SSO, registered_user_id - ) - - # Render the HTML and return. - html = self._sso_auth_success_template - respond_with_html(request, 200, html) - async def complete_sso_login( self, registered_user_id: str, diff --git a/synapse/handlers/sso.py b/synapse/handlers/sso.py index 69ffc9d9c2..dcc85e9871 100644 --- a/synapse/handlers/sso.py +++ b/synapse/handlers/sso.py @@ -22,6 +22,7 @@ from typing_extensions import NoReturn, Protocol from twisted.web.http import Request +from synapse.api.constants import LoginType from synapse.api.errors import Codes, RedirectException, SynapseError from synapse.handlers.ui_auth import UIAuthSessionDataConstants from synapse.http import get_request_user_agent @@ -147,9 +148,13 @@ class SsoHandler: self._store = hs.get_datastore() self._server_name = hs.hostname self._registration_handler = hs.get_registration_handler() + self._auth_handler = hs.get_auth_handler() self._error_template = hs.config.sso_error_template self._bad_user_template = hs.config.sso_auth_bad_user_template - self._auth_handler = hs.get_auth_handler() + + # The following template is shown after a successful user interactive + # authentication session. It tells the user they can close the window. + self._sso_auth_success_template = hs.config.sso_auth_success_template # a lock on the mappings self._mapping_lock = Linearizer(name="sso_user_mapping", clock=hs.get_clock()) @@ -598,9 +603,14 @@ class SsoHandler: ) else: # success! - await self._auth_handler.complete_sso_ui_auth( - user_id, ui_auth_session_id, request + # 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 -- cgit 1.5.1 From 4575ad0b1e86c814e6d1c3ca6ac31ba4eeeb5c66 Mon Sep 17 00:00:00 2001 From: Richard van der Hoff <1389908+richvdh@users.noreply.github.com> Date: Fri, 15 Jan 2021 13:22:12 +0000 Subject: Store an IdP ID in the OIDC session (#9109) Again in preparation for handling more than one OIDC provider, add a new caveat to the macaroon used as an OIDC session cookie, which remembers which OIDC provider we are talking to. In future, when we get a callback, we'll need it to make sure we talk to the right IdP. As part of this, I'm adding an idp_id and idp_name field to the OIDC configuration object. They aren't yet documented, and we'll just use the old values by default. --- changelog.d/9109.feature | 1 + synapse/config/oidc_config.py | 26 +++++++++++++++++++++++--- synapse/handlers/oidc_handler.py | 22 ++++++++++++++++------ tests/handlers/test_oidc.py | 3 ++- 4 files changed, 42 insertions(+), 10 deletions(-) create mode 100644 changelog.d/9109.feature (limited to 'synapse/handlers') diff --git a/changelog.d/9109.feature b/changelog.d/9109.feature new file mode 100644 index 0000000000..01a24dcf49 --- /dev/null +++ b/changelog.d/9109.feature @@ -0,0 +1 @@ +Add support for multiple SSO Identity Providers. diff --git a/synapse/config/oidc_config.py b/synapse/config/oidc_config.py index c705de5694..fddca19223 100644 --- a/synapse/config/oidc_config.py +++ b/synapse/config/oidc_config.py @@ -1,6 +1,6 @@ # -*- coding: utf-8 -*- # Copyright 2020 Quentin Gliech -# Copyright 2020 The Matrix.org Foundation C.I.C. +# Copyright 2020-2021 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. @@ -14,6 +14,7 @@ # See the License for the specific language governing permissions and # limitations under the License. +import string from typing import Optional, Type import attr @@ -38,7 +39,7 @@ class OIDCConfig(Config): oidc_config = config.get("oidc_config") if oidc_config and oidc_config.get("enabled", False): - validate_config(OIDC_PROVIDER_CONFIG_SCHEMA, oidc_config, "oidc_config") + validate_config(OIDC_PROVIDER_CONFIG_SCHEMA, oidc_config, ("oidc_config",)) self.oidc_provider = _parse_oidc_config_dict(oidc_config) if not self.oidc_provider: @@ -205,6 +206,8 @@ OIDC_PROVIDER_CONFIG_SCHEMA = { "type": "object", "required": ["issuer", "client_id", "client_secret"], "properties": { + "idp_id": {"type": "string", "minLength": 1, "maxLength": 128}, + "idp_name": {"type": "string"}, "discover": {"type": "boolean"}, "issuer": {"type": "string"}, "client_id": {"type": "string"}, @@ -277,7 +280,17 @@ def _parse_oidc_config_dict(oidc_config: JsonDict) -> "OidcProviderConfig": "methods: %s" % (", ".join(missing_methods),) ) + # MSC2858 will appy certain limits in what can be used as an IdP id, so let's + # enforce those limits now. + idp_id = oidc_config.get("idp_id", "oidc") + valid_idp_chars = set(string.ascii_letters + string.digits + "-._~") + + if any(c not in valid_idp_chars for c in idp_id): + raise ConfigError('idp_id may only contain A-Z, a-z, 0-9, "-", ".", "_", "~"') + return OidcProviderConfig( + idp_id=idp_id, + idp_name=oidc_config.get("idp_name", "OIDC"), discover=oidc_config.get("discover", True), issuer=oidc_config["issuer"], client_id=oidc_config["client_id"], @@ -296,8 +309,15 @@ def _parse_oidc_config_dict(oidc_config: JsonDict) -> "OidcProviderConfig": ) -@attr.s +@attr.s(slots=True, frozen=True) class OidcProviderConfig: + # a unique identifier for this identity provider. Used in the 'user_external_ids' + # table, as well as the query/path parameter used in the login protocol. + idp_id = attr.ib(type=str) + + # user-facing name for this identity provider. + idp_name = attr.ib(type=str) + # whether the OIDC discovery mechanism is used to discover endpoints discover = attr.ib(type=bool) diff --git a/synapse/handlers/oidc_handler.py b/synapse/handlers/oidc_handler.py index d6347bb1b8..f63a90ec5c 100644 --- a/synapse/handlers/oidc_handler.py +++ b/synapse/handlers/oidc_handler.py @@ -175,7 +175,7 @@ class OidcHandler: session_data = self._token_generator.verify_oidc_session_token( session, state ) - except MacaroonDeserializationException as e: + except (MacaroonDeserializationException, ValueError) as e: logger.exception("Invalid session") self._sso_handler.render_error(request, "invalid_session", str(e)) return @@ -253,10 +253,10 @@ class OidcProvider: self._server_name = hs.config.server_name # type: str # identifier for the external_ids table - self.idp_id = "oidc" + self.idp_id = provider.idp_id # user-facing name of this auth provider - self.idp_name = "OIDC" + self.idp_name = provider.idp_name self._sso_handler = hs.get_sso_handler() @@ -656,6 +656,7 @@ class OidcProvider: cookie = self._token_generator.generate_oidc_session_token( state=state, session_data=OidcSessionData( + idp_id=self.idp_id, nonce=nonce, client_redirect_url=client_redirect_url.decode(), ui_auth_session_id=ui_auth_session_id, @@ -924,6 +925,7 @@ class OidcSessionTokenGenerator: macaroon.add_first_party_caveat("gen = 1") macaroon.add_first_party_caveat("type = session") macaroon.add_first_party_caveat("state = %s" % (state,)) + macaroon.add_first_party_caveat("idp_id = %s" % (session_data.idp_id,)) macaroon.add_first_party_caveat("nonce = %s" % (session_data.nonce,)) macaroon.add_first_party_caveat( "client_redirect_url = %s" % (session_data.client_redirect_url,) @@ -952,6 +954,9 @@ class OidcSessionTokenGenerator: Returns: The data extracted from the session cookie + + Raises: + ValueError if an expected caveat is missing from the macaroon. """ macaroon = pymacaroons.Macaroon.deserialize(session) @@ -960,6 +965,7 @@ class OidcSessionTokenGenerator: v.satisfy_exact("type = session") v.satisfy_exact("state = %s" % (state,)) v.satisfy_general(lambda c: c.startswith("nonce = ")) + v.satisfy_general(lambda c: c.startswith("idp_id = ")) v.satisfy_general(lambda c: c.startswith("client_redirect_url = ")) # Sometimes there's a UI auth session ID, it seems to be OK to attempt # to always satisfy this. @@ -968,9 +974,9 @@ class OidcSessionTokenGenerator: v.verify(macaroon, self._macaroon_secret_key) - # Extract the `nonce`, `client_redirect_url`, and maybe the - # `ui_auth_session_id` from the token. + # Extract the session data from the token. nonce = self._get_value_from_macaroon(macaroon, "nonce") + idp_id = self._get_value_from_macaroon(macaroon, "idp_id") client_redirect_url = self._get_value_from_macaroon( macaroon, "client_redirect_url" ) @@ -983,6 +989,7 @@ class OidcSessionTokenGenerator: return OidcSessionData( nonce=nonce, + idp_id=idp_id, client_redirect_url=client_redirect_url, ui_auth_session_id=ui_auth_session_id, ) @@ -998,7 +1005,7 @@ class OidcSessionTokenGenerator: The extracted value Raises: - Exception: if the caveat was not in the macaroon + ValueError: if the caveat was not in the macaroon """ prefix = key + " = " for caveat in macaroon.caveats: @@ -1019,6 +1026,9 @@ class OidcSessionTokenGenerator: class OidcSessionData: """The attributes which are stored in a OIDC session cookie""" + # the Identity Provider being used + idp_id = attr.ib(type=str) + # The `nonce` parameter passed to the OIDC provider. nonce = attr.ib(type=str) diff --git a/tests/handlers/test_oidc.py b/tests/handlers/test_oidc.py index 5d338bea87..38ae8ca19e 100644 --- a/tests/handlers/test_oidc.py +++ b/tests/handlers/test_oidc.py @@ -848,6 +848,7 @@ class OidcHandlerTestCase(HomeserverTestCase): return self.handler._token_generator.generate_oidc_session_token( state=state, session_data=OidcSessionData( + idp_id="oidc", nonce=nonce, client_redirect_url=client_redirect_url, ui_auth_session_id=ui_auth_session_id, @@ -990,7 +991,7 @@ async def _make_callback_with_userinfo( session = handler._token_generator.generate_oidc_session_token( state=state, session_data=OidcSessionData( - nonce="nonce", client_redirect_url=client_redirect_url, + idp_id="oidc", nonce="nonce", client_redirect_url=client_redirect_url, ), ) request = _build_callback_request("code", state, session) -- cgit 1.5.1