Collect terms consent from the user during SSO registration (#9276)

changelog.d/9276.feature

@@ -0,0 +1 @@
+Improve the user experience of setting up an account via single-sign on.

docs/sample_config.yaml

@@ -2003,6 +2003,28 @@ sso:
  #
  # * username: the localpart of the user's chosen user id
  #
+ # * HTML page allowing the user to consent to the server's terms and
+ # conditions. This is only shown for new users, and only if
+ # `user_consent.require_at_registration` is set.
+ #
+ # When rendering, this template is given the following variables:
+ #
+ # * server_name: the homeserver's name.
+ #
+ # * user_id: the user's matrix proposed ID.
+ #
+ # * user_profile.display_name: the user's proposed display name, if any.
+ #
+ # * consent_version: the version of the terms that the user will be
+ # shown
+ #
+ # * terms_url: a link to the page showing the terms.
+ #
+ # The template should render a form which submits the following fields:
+ #
+ # * accepted_version: the version of the terms accepted by the user
+ # (ie, 'consent_version' from the input variables).
+ #
  # * HTML page for a confirmation step before redirecting back to the client
  # with the login token: 'sso_redirect_confirm.html'.
  #

docs/workers.md

@@ -259,6 +259,7 @@ using):
  ^/_matrix/client/(api/v1|r0|unstable)/login/sso/redirect
  ^/_synapse/client/pick_idp$
  ^/_synapse/client/pick_username
+ ^/_synapse/client/new_user_consent$
  ^/_synapse/client/sso_register$
 
  # OpenID Connect requests.

synapse/config/sso.py

@@ -158,6 +158,28 @@ def generate_config_section(self, **kwargs):
  #
  # * username: the localpart of the user's chosen user id
  #
+ # * HTML page allowing the user to consent to the server's terms and
+ # conditions. This is only shown for new users, and only if
+ # `user_consent.require_at_registration` is set.
+ #
+ # When rendering, this template is given the following variables:
+ #
+ # * server_name: the homeserver's name.
+ #
+ # * user_id: the user's matrix proposed ID.
+ #
+ # * user_profile.display_name: the user's proposed display name, if any.
+ #
+ # * consent_version: the version of the terms that the user will be
+ # shown
+ #
+ # * terms_url: a link to the page showing the terms.
+ #
+ # The template should render a form which submits the following fields:
+ #
+ # * accepted_version: the version of the terms accepted by the user
+ # (ie, 'consent_version' from the input variables).
+ #
  # * HTML page for a confirmation step before redirecting back to the client
  # with the login token: 'sso_redirect_confirm.html'.
  #

synapse/handlers/register.py

@@ -694,6 +694,8 @@ async def post_registration_actions(
  access_token: The access token of the newly logged in device, or
  None if `inhibit_login` enabled.
  """
+ # TODO: 3pid registration can actually happen on the workers. Consider
+ # refactoring it.
  if self.hs.config.worker_app:
  await self._post_registration_client(
  user_id=user_id, auth_result=auth_result, access_token=access_token

synapse/handlers/sso.py

@@ -155,6 +155,7 @@ class UsernameMappingSession:
  chosen_localpart = attr.ib(type=Optional[str], default=None)
  use_display_name = attr.ib(type=bool, default=True)
  emails_to_use = attr.ib(type=Collection[str], default=())
+ terms_accepted_version = attr.ib(type=Optional[str], default=None)
 
 
 # the HTTP cookie used to track the mapping session id
@@ -190,6 +191,8 @@ def __init__(self, hs: "HomeServer"):
  # map from idp_id to SsoIdentityProvider
  self._identity_providers = {} # type: Dict[str, SsoIdentityProvider]
 
+ self._consent_at_registration = hs.config.consent.user_consent_at_registration
+
  def register_identity_provider(self, p: SsoIdentityProvider):
  p_id = p.idp_id
  assert p_id not in self._identity_providers
@@ -761,6 +764,38 @@ async def handle_submit_username_request(
  )
  session.emails_to_use = filtered_emails
 
+ # we may now need to collect consent from the user, in which case, redirect
+ # to the consent-extraction-unit
+ if self._consent_at_registration:
+ redirect_url = b"/_synapse/client/new_user_consent"
+
+ # otherwise, redirect to the completion page
+ else:
+ redirect_url = b"/_synapse/client/sso_register"
+
+ respond_with_redirect(request, redirect_url)
+
+ async def handle_terms_accepted(
+ self, request: Request, session_id: str, terms_version: str
+ ):
+ """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,
+ )
+ session = self.get_mapping_session(session_id)
+ session.terms_accepted_version = terms_version
+
  # we're done; now we can register the user
  respond_with_redirect(request, b"/_synapse/client/sso_register")
 
@@ -816,6 +851,15 @@ async def register_sso_user(self, request: Request, session_id: str) -> None:
  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,
  request,

synapse/res/templates/sso_new_user_consent.html

@@ -0,0 +1,39 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+ <meta charset="UTF-8">
+ <title>SSO redirect confirmation</title>
+ <meta name="viewport" content="width=device-width, user-scalable=no">
+ <style type="text/css">
+ {% include "sso.css" without context %}
+
+ #consent_form {
+ margin-top: 56px;
+ }
+ </style>
+</head>
+ <body>
+ <header>
+ <h1>Your account is nearly ready</h1>
+ <p>Agree to the terms to create your account.</p>
+ </header>
+ <main>
+ <!-- {% if user_profile.avatar_url and user_profile.display_name %} -->
+ <div class="profile">
+ <img src="{{ user_profile.avatar_url | mxc_to_http(64, 64) }}" class="avatar" />
+ <div class="profile-details">
+ <div class="display-name">{{ user_profile.display_name }}</div>
+ <div class="user-id">{{ user_id }}</div>
+ </div>
+ </div>
+ <!-- {% endif %} -->
+ <form method="post" action="{{my_url}}" id="consent_form">
+ <p>
+ <input id="accepted_version" type="checkbox" name="accepted_version" value="{{ consent_version }}" required>
+ <label for="accepted_version">I have read and agree to the <a href="{{ terms_url }}" target="_blank">terms and conditions</a>.</label>
+ </p>
+ <input type="submit" class="primary-button" value="Continue"/>
+ </form>
+ </main>
+ </body>
+</html>

synapse/rest/synapse/client/__init__.py

@@ -17,6 +17,7 @@
 
 from twisted.web.resource import Resource
 
+from synapse.rest.synapse.client.new_user_consent import NewUserConsentResource
 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
@@ -39,6 +40,7 @@ def build_synapse_client_resource_tree(hs: "HomeServer") -> Mapping[str, Resourc
  # enabled (they just won't work very well if it's not)
  "/_synapse/client/pick_idp": PickIdpResource(hs),
  "/_synapse/client/pick_username": pick_username_resource(hs),
+ "/_synapse/client/new_user_consent": NewUserConsentResource(hs),
  "/_synapse/client/sso_register": SsoRegisterResource(hs),
  }
 

synapse/rest/synapse/client/new_user_consent.py

@@ -0,0 +1,97 @@
+# -*- 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, respond_with_html
+from synapse.http.servlet import parse_string
+from synapse.types import UserID
+from synapse.util.templates import build_jinja_env
+
+if TYPE_CHECKING:
+ from synapse.server import HomeServer
+
+logger = logging.getLogger(__name__)
+
+
+class NewUserConsentResource(DirectServeHtmlResource):
+ """A resource which collects consent to the server's terms from a new user
+
+ This resource gets mounted at /_synapse/client/new_user_consent, and is shown
+ when we are automatically creating a new user due to an SSO login.
+
+ It shows a template which prompts the user to go and read the Ts and Cs, and click
+ a clickybox if they have done so.
+ """
+
+ def __init__(self, hs: "HomeServer"):
+ super().__init__()
+ self._sso_handler = hs.get_sso_handler()
+ self._server_name = hs.hostname
+ self._consent_version = hs.config.consent.user_consent_version
+
+ def template_search_dirs():
+ if hs.config.sso.sso_template_dir:
+ yield hs.config.sso.sso_template_dir
+ yield hs.config.sso.default_template_dir
+
+ self._jinja_env = build_jinja_env(template_search_dirs(), hs.config)
+
+ async def _async_render_GET(self, request: Request) -> None:
+ try:
+ session_id = get_username_mapping_session_cookie_from_request(request)
+ session = self._sso_handler.get_mapping_session(session_id)
+ except SynapseError as e:
+ logger.warning("Error fetching session: %s", e)
+ self._sso_handler.render_error(request, "bad_session", e.msg, code=e.code)
+ return
+
+ user_id = UserID(session.chosen_localpart, self._server_name)
+ user_profile = {
+ "display_name": session.display_name,
+ }
+
+ template_params = {
+ "user_id": user_id.to_string(),
+ "user_profile": user_profile,
+ "consent_version": self._consent_version,
+ "terms_url": "/_matrix/consent?v=%s" % (self._consent_version,),
+ }
+
+ template = self._jinja_env.get_template("sso_new_user_consent.html")
+ html = template.render(template_params)
+ respond_with_html(request, 200, html)
+
+ async def _async_render_POST(self, request: Request):
+ 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
+
+ try:
+ accepted_version = parse_string(request, "accepted_version", required=True)
+ except SynapseError as e:
+ self._sso_handler.render_error(request, "bad_param", e.msg, code=e.code)
+ return
+
+ await self._sso_handler.handle_terms_accepted(
+ request, session_id, accepted_version
+ )