From f78d07bf005f7212bcc74256721677a3b255ea0e Mon Sep 17 00:00:00 2001 From: Richard van der Hoff <1389908+richvdh@users.noreply.github.com> Date: Mon, 1 Feb 2021 13:15:51 +0000 Subject: [PATCH] Split out a separate endpoint to complete SSO registration (#9262) There are going to be a couple of paths to get to the final step of SSO reg, and I want the URL in the browser to consistent. So, let's move the final step onto a separate path, which we redirect to. --- changelog.d/9262.feature | 1 + synapse/app/homeserver.py | 2 + synapse/handlers/sso.py | 81 ++++++++++++++++---- synapse/http/server.py | 7 ++ synapse/rest/synapse/client/pick_username.py | 16 ++-- synapse/rest/synapse/client/sso_register.py | 50 ++++++++++++ tests/rest/client/v1/test_login.py | 14 +++- 7 files changed, 145 insertions(+), 26 deletions(-) create mode 100644 changelog.d/9262.feature create mode 100644 synapse/rest/synapse/client/sso_register.py diff --git a/changelog.d/9262.feature b/changelog.d/9262.feature new file mode 100644 index 0000000000..c21b197ca1 --- /dev/null +++ b/changelog.d/9262.feature @@ -0,0 +1 @@ +Improve the user experience of setting up an account via single-sign on. diff --git a/synapse/app/homeserver.py b/synapse/app/homeserver.py index 57a2f5237c..86d6f73674 100644 --- a/synapse/app/homeserver.py +++ b/synapse/app/homeserver.py @@ -62,6 +62,7 @@ from synapse.rest.health import HealthResource from synapse.rest.key.v2 import KeyApiV2Resource from synapse.rest.synapse.client.pick_idp import PickIdpResource from synapse.rest.synapse.client.pick_username import pick_username_resource +from synapse.rest.synapse.client.sso_register import SsoRegisterResource from synapse.rest.well_known import WellKnownResource from synapse.server import HomeServer from synapse.storage import DataStore @@ -192,6 +193,7 @@ class SynapseHomeServer(HomeServer): "/_synapse/admin": AdminRestResource(self), "/_synapse/client/pick_username": pick_username_resource(self), "/_synapse/client/pick_idp": PickIdpResource(self), + "/_synapse/client/sso_register": SsoRegisterResource(self), } ) diff --git a/synapse/handlers/sso.py b/synapse/handlers/sso.py index 3308b037d2..50c5ae142a 100644 --- a/synapse/handlers/sso.py +++ b/synapse/handlers/sso.py @@ -21,12 +21,13 @@ import attr from typing_extensions import NoReturn, Protocol from twisted.web.http import Request +from twisted.web.iweb import IRequest from synapse.api.constants import LoginType from synapse.api.errors import Codes, NotFoundError, 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.server import respond_with_html, respond_with_redirect from synapse.http.site import SynapseRequest from synapse.types import JsonDict, UserID, contains_invalid_mxid_characters from synapse.util.async_helpers import Linearizer @@ -141,6 +142,9 @@ class UsernameMappingSession: # expiry time for the session, in milliseconds expiry_time_ms = attr.ib(type=int) + # choices made by the user + chosen_localpart = attr.ib(type=Optional[str], default=None) + # the HTTP cookie used to track the mapping session id USERNAME_MAPPING_SESSION_COOKIE_NAME = b"username_mapping_session" @@ -647,6 +651,25 @@ class SsoHandler: ) 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: @@ -663,12 +686,7 @@ class SsoHandler: # make sure that there is a valid mapping session, to stop people dictionary- # scanning for accounts - - self._expire_old_sessions() - session = self._username_mapping_sessions.get(session_id) - if not session: - logger.info("Couldn't find session id %s", session_id) - raise SynapseError(400, "unknown session") + self.get_mapping_session(session_id) logger.info( "[session %s] Checking for availability of username %s", @@ -696,16 +714,33 @@ class SsoHandler: localpart: localpart requested by the user session_id: ID of the username mapping session, extracted from a cookie """ - self._expire_old_sessions() - session = self._username_mapping_sessions.get(session_id) - if not session: - logger.info("Couldn't find session id %s", session_id) - raise SynapseError(400, "unknown session") + session = self.get_mapping_session(session_id) - logger.info("[session %s] Registering localpart %s", session_id, localpart) + # update the session with the user's choices + session.chosen_localpart = localpart + + # we're done; now we can register the user + respond_with_redirect(request, b"/_synapse/client/sso_register") + + 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 + """ + session = self.get_mapping_session(session_id) + + logger.info( + "[session %s] Registering localpart %s", + session_id, + session.chosen_localpart, + ) attributes = UserAttributes( - localpart=localpart, + localpart=session.chosen_localpart, display_name=session.display_name, emails=session.emails, ) @@ -720,7 +755,12 @@ class SsoHandler: request.getClientIP(), ) - logger.info("[session %s] Registered userid %s", session_id, user_id) + 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] @@ -751,3 +791,14 @@ class SsoHandler: for session_id in to_expire: logger.info("Expiring mapping session %s", session_id) del self._username_mapping_sessions[session_id] + + +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") diff --git a/synapse/http/server.py b/synapse/http/server.py index d69d579b3a..8249732b27 100644 --- a/synapse/http/server.py +++ b/synapse/http/server.py @@ -761,6 +761,13 @@ def set_clickjacking_protection_headers(request: Request): request.setHeader(b"Content-Security-Policy", b"frame-ancestors 'none';") +def respond_with_redirect(request: Request, url: bytes) -> None: + """Write a 302 response to the request, if it is still alive.""" + logger.debug("Redirect to %s", url.decode("utf-8")) + request.redirect(url) + finish_request(request) + + def finish_request(request: Request): """ Finish writing the response to the request. diff --git a/synapse/rest/synapse/client/pick_username.py b/synapse/rest/synapse/client/pick_username.py index d3b6803e65..1bc737bad0 100644 --- a/synapse/rest/synapse/client/pick_username.py +++ b/synapse/rest/synapse/client/pick_username.py @@ -12,6 +12,7 @@ # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. + from typing import TYPE_CHECKING import pkg_resources @@ -20,8 +21,7 @@ from twisted.web.http import Request from twisted.web.resource import Resource from twisted.web.static import File -from synapse.api.errors import SynapseError -from synapse.handlers.sso import USERNAME_MAPPING_SESSION_COOKIE_NAME +from synapse.handlers.sso import get_username_mapping_session_cookie_from_request from synapse.http.server import DirectServeHtmlResource, DirectServeJsonResource from synapse.http.servlet import parse_string from synapse.http.site import SynapseRequest @@ -61,12 +61,10 @@ class AvailabilityCheckResource(DirectServeJsonResource): async def _async_render_GET(self, request: Request): localpart = parse_string(request, "username", required=True) - session_id = request.getCookie(USERNAME_MAPPING_SESSION_COOKIE_NAME) - if not session_id: - raise SynapseError(code=400, msg="missing session_id") + session_id = get_username_mapping_session_cookie_from_request(request) is_available = await self._sso_handler.check_username_availability( - localpart, session_id.decode("ascii", errors="replace") + localpart, session_id ) return 200, {"available": is_available} @@ -79,10 +77,8 @@ class SubmitResource(DirectServeHtmlResource): async def _async_render_POST(self, request: SynapseRequest): localpart = parse_string(request, "username", required=True) - session_id = request.getCookie(USERNAME_MAPPING_SESSION_COOKIE_NAME) - if not session_id: - raise SynapseError(code=400, msg="missing session_id") + session_id = get_username_mapping_session_cookie_from_request(request) await self._sso_handler.handle_submit_username_request( - request, localpart, session_id.decode("ascii", errors="replace") + request, localpart, session_id ) diff --git a/synapse/rest/synapse/client/sso_register.py b/synapse/rest/synapse/client/sso_register.py new file mode 100644 index 0000000000..dfefeb7796 --- /dev/null +++ b/synapse/rest/synapse/client/sso_register.py @@ -0,0 +1,50 @@ +# -*- coding: utf-8 -*- +# Copyright 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. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + +import logging +from typing import TYPE_CHECKING + +from twisted.web.http import Request + +from synapse.api.errors import SynapseError +from synapse.handlers.sso import get_username_mapping_session_cookie_from_request +from synapse.http.server import DirectServeHtmlResource + +if TYPE_CHECKING: + from synapse.server import HomeServer + +logger = logging.getLogger(__name__) + + +class SsoRegisterResource(DirectServeHtmlResource): + """A resource which completes SSO registration + + This resource gets mounted at /_synapse/client/sso_register, and is shown + after we collect username and/or consent for a new SSO user. It (finally) registers + the user, and confirms redirect to the client + """ + + def __init__(self, hs: "HomeServer"): + super().__init__() + self._sso_handler = hs.get_sso_handler() + + async def _async_render_GET(self, request: Request) -> None: + try: + session_id = get_username_mapping_session_cookie_from_request(request) + except SynapseError as e: + logger.warning("Error fetching session cookie: %s", e) + self._sso_handler.render_error(request, "bad_session", e.msg, code=e.code) + return + await self._sso_handler.register_sso_user(request, session_id) diff --git a/tests/rest/client/v1/test_login.py b/tests/rest/client/v1/test_login.py index e2bb945453..f01215ed1c 100644 --- a/tests/rest/client/v1/test_login.py +++ b/tests/rest/client/v1/test_login.py @@ -31,6 +31,7 @@ from synapse.rest.client.v2_alpha import devices, register from synapse.rest.client.v2_alpha.account import WhoamiRestServlet from synapse.rest.synapse.client.pick_idp import PickIdpResource from synapse.rest.synapse.client.pick_username import pick_username_resource +from synapse.rest.synapse.client.sso_register import SsoRegisterResource from synapse.types import create_requester from tests import unittest @@ -1215,6 +1216,7 @@ class UsernamePickerTestCase(HomeserverTestCase): d = super().create_resource_dict() d["/_synapse/client/pick_username"] = pick_username_resource(self.hs) + d["/_synapse/client/sso_register"] = SsoRegisterResource(self.hs) d["/_synapse/oidc"] = OIDCResource(self.hs) return d @@ -1253,7 +1255,7 @@ class UsernamePickerTestCase(HomeserverTestCase): self.assertApproximates(session.expiry_time_ms, expected_expiry, tolerance=1000) # Now, submit a username to the username picker, which should serve a redirect - # back to the client + # to the completion page submit_path = picker_url + "/submit" content = urlencode({b"username": b"bobby"}).encode("utf8") chan = self.make_request( @@ -1270,6 +1272,16 @@ class UsernamePickerTestCase(HomeserverTestCase): ) self.assertEqual(chan.code, 302, chan.result) location_headers = chan.headers.getRawHeaders("Location") + + # send a request to the completion page, which should 302 to the client redirectUrl + chan = self.make_request( + "GET", + path=location_headers[0], + custom_headers=[("Cookie", "username_mapping_session=" + session_id)], + ) + self.assertEqual(chan.code, 302, chan.result) + location_headers = chan.headers.getRawHeaders("Location") + # ensure that the returned location matches the requested redirect URL path, query = location_headers[0].split("?", 1) self.assertEqual(path, "https://x")