From b2bd54a2e31d9a248f73fadb184ae9b4cbdb49f9 Mon Sep 17 00:00:00 2001 From: Brendan Abolivier Date: Mon, 2 Mar 2020 16:36:32 +0000 Subject: [PATCH] Add a confirmation step to the SSO login flow --- docs/sample_config.yaml | 34 ++++++++ synapse/config/_base.pyi | 2 + synapse/config/homeserver.py | 2 + synapse/config/sso.py | 74 ++++++++++++++++ .../res/templates/sso_redirect_confirm.html | 14 +++ synapse/rest/client/v1/login.py | 40 +++++++-- tests/rest/client/v1/test_login.py | 85 +++++++++++++++++++ 7 files changed, 245 insertions(+), 6 deletions(-) create mode 100644 synapse/config/sso.py create mode 100644 synapse/res/templates/sso_redirect_confirm.html diff --git a/docs/sample_config.yaml b/docs/sample_config.yaml index 8a036071e1..bbb8a4d934 100644 --- a/docs/sample_config.yaml +++ b/docs/sample_config.yaml @@ -1360,6 +1360,40 @@ saml2_config: # # name: value +# Additional settings to use with single-sign on systems such as SAML2 and CAS. +# +sso: + # Directory in which Synapse will try to find the template files below. + # If not set, default templates from within the Synapse package will be used. + # + # DO NOT UNCOMMENT THIS SETTING unless you want to customise the templates. + # If you *do* uncomment it, you will need to make sure that all the templates + # below are in the directory. + # + # Synapse will look for the following templates in this directory: + # + # * HTML page for confirmation of redirect during authentication: + # 'sso_redirect_confirm.html'. + # + # When rendering, this template is given three variables: + # * redirect_url: the URL the user is about to be redirected to. Needs + # manual escaping (see + # https://jinja.palletsprojects.com/en/2.11.x/templates/#html-escaping). + # + # * display_url: the same as `redirect_url`, but with the query + # parameters stripped. The intention is to have a + # human-readable URL to show to users, not to use it as + # the final address to redirect to. Needs manual escaping + # (see https://jinja.palletsprojects.com/en/2.11.x/templates/#html-escaping). + # + # * server_name: the homeserver's name. + # + # You can see the default templates at: + # https://github.com/matrix-org/synapse/tree/master/synapse/res/templates + # + #template_dir: "res/templates" + + # The JWT needs to contain a globally unique "sub" (subject) claim. # #jwt_config: diff --git a/synapse/config/_base.pyi b/synapse/config/_base.pyi index 86bc965ee4..3053fc9d27 100644 --- a/synapse/config/_base.pyi +++ b/synapse/config/_base.pyi @@ -24,6 +24,7 @@ from synapse.config import ( server, server_notices_config, spam_checker, + sso, stats, third_party_event_rules, tls, @@ -57,6 +58,7 @@ class RootConfig: key: key.KeyConfig saml2: saml2_config.SAML2Config cas: cas.CasConfig + sso: sso.SSOConfig jwt: jwt_config.JWTConfig password: password.PasswordConfig email: emailconfig.EmailConfig diff --git a/synapse/config/homeserver.py b/synapse/config/homeserver.py index 6e348671c7..b4bca08b20 100644 --- a/synapse/config/homeserver.py +++ b/synapse/config/homeserver.py @@ -38,6 +38,7 @@ from .saml2_config import SAML2Config from .server import ServerConfig from .server_notices_config import ServerNoticesConfig from .spam_checker import SpamCheckerConfig +from .sso import SSOConfig from .stats import StatsConfig from .third_party_event_rules import ThirdPartyRulesConfig from .tls import TlsConfig @@ -65,6 +66,7 @@ class HomeServerConfig(RootConfig): KeyConfig, SAML2Config, CasConfig, + SSOConfig, JWTConfig, PasswordConfig, EmailConfig, diff --git a/synapse/config/sso.py b/synapse/config/sso.py new file mode 100644 index 0000000000..f426b65b4f --- /dev/null +++ b/synapse/config/sso.py @@ -0,0 +1,74 @@ +# -*- coding: utf-8 -*- +# Copyright 2020 The Matrix.org Foundation C.I.C. +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# 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. +from typing import Any, Dict + +import pkg_resources + +from ._base import Config, ConfigError + + +class SSOConfig(Config): + """SSO Configuration + """ + + section = "sso" + + def read_config(self, config, **kwargs): + sso_config = config.get("sso") or {} # type: Dict[str, Any] + + # Pick a template directory in order of: + # * The sso-specific template_dir + # * /path/to/synapse/install/res/templates + template_dir = sso_config.get("template_dir") + if not template_dir: + template_dir = pkg_resources.resource_filename("synapse", "res/templates",) + + self.sso_redirect_confirm_template_dir = template_dir + + def generate_config_section(self, **kwargs): + return """\ + # Additional settings to use with single-sign on systems such as SAML2 and CAS. + # + sso: + # Directory in which Synapse will try to find the template files below. + # If not set, default templates from within the Synapse package will be used. + # + # DO NOT UNCOMMENT THIS SETTING unless you want to customise the templates. + # If you *do* uncomment it, you will need to make sure that all the templates + # below are in the directory. + # + # Synapse will look for the following templates in this directory: + # + # * HTML page for a confirmation step before redirecting back to the client + # with the login token: 'sso_redirect_confirm.html'. + # + # When rendering, this template is given three variables: + # * redirect_url: the URL the user is about to be redirected to. Needs + # manual escaping (see + # https://jinja.palletsprojects.com/en/2.11.x/templates/#html-escaping). + # + # * display_url: the same as `redirect_url`, but with the query + # parameters stripped. The intention is to have a + # human-readable URL to show to users, not to use it as + # the final address to redirect to. Needs manual escaping + # (see https://jinja.palletsprojects.com/en/2.11.x/templates/#html-escaping). + # + # * server_name: the homeserver's name. + # + # You can see the default templates at: + # https://github.com/matrix-org/synapse/tree/master/synapse/res/templates + # + #template_dir: "res/templates" + """ diff --git a/synapse/res/templates/sso_redirect_confirm.html b/synapse/res/templates/sso_redirect_confirm.html new file mode 100644 index 0000000000..20a15e1e74 --- /dev/null +++ b/synapse/res/templates/sso_redirect_confirm.html @@ -0,0 +1,14 @@ + + + + + SSO redirect confirmation + + +

The application at {{ display_url | e }} is requesting full access to your {{ server_name }} Matrix account.

+

If you don't recognise this address, you should ignore this and close this tab.

+

+ I trust this address +

+ + \ No newline at end of file diff --git a/synapse/rest/client/v1/login.py b/synapse/rest/client/v1/login.py index 1294e080dc..1acfd01d8e 100644 --- a/synapse/rest/client/v1/login.py +++ b/synapse/rest/client/v1/login.py @@ -29,6 +29,7 @@ from synapse.http.servlet import ( parse_string, ) from synapse.http.site import SynapseRequest +from synapse.push.mailer import load_jinja2_templates from synapse.rest.client.v2_alpha._base import client_patterns from synapse.rest.well_known import WellKnownBuilder from synapse.types import UserID, map_username_to_mxid_localpart @@ -548,6 +549,13 @@ class SSOAuthHandler(object): self._registration_handler = hs.get_registration_handler() self._macaroon_gen = hs.get_macaroon_generator() + # Load the redirect page HTML template + self._template = load_jinja2_templates( + hs.config.sso_redirect_confirm_template_dir, ["sso_redirect_confirm.html"], + )[0] + + self._server_name = hs.config.server_name + async def on_successful_auth( self, username, request, client_redirect_url, user_display_name=None ): @@ -592,21 +600,41 @@ class SSOAuthHandler(object): request: client_redirect_url: """ - + # Create a login token login_token = self._macaroon_gen.generate_short_term_login_token( registered_user_id ) - redirect_url = self._add_login_token_to_redirect_url( - client_redirect_url, login_token + + # Remove the query parameters from the redirect URL to get a shorter version of + # it. This is only to display a human-readable URL in the template, but not the + # URL we redirect users to. + redirect_url_no_params = client_redirect_url.split("?")[0] + + # Append the login token to the original redirect URL (i.e. with its query + # parameters kept intact) to build the URL to which the template needs to + # redirect the users once they have clicked on the confirmation link. + redirect_url = self._add_query_param_to_url( + client_redirect_url, "loginToken", login_token ) - request.redirect(redirect_url) + + # Serve the redirect confirmation page + html = self._template.render( + display_url=redirect_url_no_params, + redirect_url=redirect_url, + server_name=self._server_name, + ) + + request.setResponseCode(200) + request.setHeader(b"Content-Type", b"text/html; charset=utf-8") + request.setHeader(b"Content-Length", b"%d" % (len(html),)) + request.write(html.encode("utf8")) finish_request(request) @staticmethod - def _add_login_token_to_redirect_url(url, token): + def _add_query_param_to_url(url, param_name, param): url_parts = list(urllib.parse.urlparse(url)) query = dict(urllib.parse.parse_qsl(url_parts[4])) - query.update({"loginToken": token}) + query.update({param_name: param}) url_parts[4] = urllib.parse.urlencode(query) return urllib.parse.urlunparse(url_parts) diff --git a/tests/rest/client/v1/test_login.py b/tests/rest/client/v1/test_login.py index eae5411325..2b8ad5c753 100644 --- a/tests/rest/client/v1/test_login.py +++ b/tests/rest/client/v1/test_login.py @@ -1,4 +1,7 @@ import json +import urllib.parse + +from mock import Mock import synapse.rest.admin from synapse.rest.client.v1 import login @@ -252,3 +255,85 @@ class LoginRestServletTestCase(unittest.HomeserverTestCase): ) self.render(request) self.assertEquals(channel.code, 200, channel.result) + + +class CASRedirectConfirmTestCase(unittest.HomeserverTestCase): + + servlets = [ + login.register_servlets, + ] + + def make_homeserver(self, reactor, clock): + self.base_url = "https://matrix.goodserver.com/" + self.redirect_path = "_synapse/client/login/sso/redirect/confirm" + + config = self.default_config() + config["enable_registration"] = True + config["cas_config"] = { + "enabled": True, + "server_url": "https://fake.test", + "service_url": "https://matrix.goodserver.com:8448", + } + config["public_baseurl"] = self.base_url + + async def get_raw(uri, args): + """Return an example response payload from a call to the `/proxyValidate` + endpoint of a CAS server, copied from + https://apereo.github.io/cas/5.0.x/protocol/CAS-Protocol-V2-Specification.html#26-proxyvalidate-cas-20 + + This needs to be returned by an async function (as opposed to set as the + mock's return value) because the corresponding Synapse code awaits on it. + """ + return """ + + + username + PGTIOU-84678-8a9d... + + https://proxy2/pgtUrl + https://proxy1/pgtUrl + + + + """ + + mocked_http_client = Mock(spec=["get_raw"]) + mocked_http_client.get_raw.side_effect = get_raw + + self.hs = self.setup_test_homeserver( + config=config, proxied_http_client=mocked_http_client, + ) + + return self.hs + + def test_cas_redirect_confirm(self): + """Tests that the SSO login flow serves a confirmation page before redirecting a + user to the redirect URL. + """ + base_url = "/login/cas/ticket?redirectUrl" + redirect_url = "https://dodgy-site.com/" + + url_parts = list(urllib.parse.urlparse(base_url)) + query = dict(urllib.parse.parse_qsl(url_parts[4])) + query.update({"redirectUrl": redirect_url}) + query.update({"ticket": "ticket"}) + url_parts[4] = urllib.parse.urlencode(query) + cas_ticket_url = urllib.parse.urlunparse(url_parts) + + # Get Synapse to call the fake CAS and serve the template. + request, channel = self.make_request("GET", cas_ticket_url) + self.render(request) + + # Test that the response is HTML. + content_type_header_value = "" + for header in channel.result.get("headers", []): + if header[0] == b"Content-Type": + content_type_header_value = header[1].decode("utf8") + + self.assertTrue(content_type_header_value.startswith("text/html")) + + # Test that the body isn't empty. + self.assertTrue(len(channel.result["body"]) > 0) + + # And that it contains our redirect link + self.assertIn(redirect_url, channel.result["body"].decode("UTF-8"))