From 5ad5b73e2a82eb4adc31f48862fe519bb0e9255b Mon Sep 17 00:00:00 2001 From: Patrick Cloke Date: Mon, 16 Nov 2020 13:40:10 -0500 Subject: [PATCH] Abstract rendering errors. --- synapse/handlers/oidc_handler.py | 56 +++++++++++--------------------- synapse/handlers/saml_handler.py | 35 ++++---------------- synapse/handlers/sso.py | 54 ++++++++++++++++++++++++++++++ synapse/server.py | 5 +++ tests/handlers/test_oidc.py | 14 ++++---- 5 files changed, 92 insertions(+), 72 deletions(-) create mode 100644 synapse/handlers/sso.py diff --git a/synapse/handlers/oidc_handler.py b/synapse/handlers/oidc_handler.py index ed5d52c2f5..57f30e5d83 100644 --- a/synapse/handlers/oidc_handler.py +++ b/synapse/handlers/oidc_handler.py @@ -35,7 +35,7 @@ from twisted.web.client import readBody from synapse.config import ConfigError from synapse.handlers._base import BaseHandler -from synapse.http.server import respond_with_html +from synapse.handlers.sso import MappingException from synapse.http.site import SynapseRequest from synapse.logging.context import make_deferred_yieldable from synapse.types import JsonDict, UserID, map_username_to_mxid_localpart @@ -84,10 +84,6 @@ class OidcError(Exception): return self.error -class MappingException(Exception): - """Used to catch errors when mapping the SAML2 response to a user.""" - - class OidcHandler(BaseHandler): """Handles requests related to the OpenID Connect login flow. """ @@ -122,31 +118,11 @@ class OidcHandler(BaseHandler): self._registration_handler = hs.get_registration_handler() self._server_name = hs.config.server_name # type: str self._macaroon_secret_key = hs.config.macaroon_secret_key - self._error_template = hs.config.sso_error_template # identifier for the external_ids table self._auth_provider_id = "oidc" - def _render_error( - self, request, error: str, error_description: Optional[str] = None - ) -> None: - """Render the error template and respond to the request with it. - - This is used to show errors to the user. The template of this page can - be found under `synapse/res/templates/sso_error.html`. - - Args: - request: The incoming request from the browser. - We'll respond with an HTML page describing the error. - error: A technical identifier for this error. Those include - well-known OAuth2/OIDC error types like invalid_request or - access_denied. - error_description: A human-readable description of the error. - """ - html = self._error_template.render( - error=error, error_description=error_description - ) - respond_with_html(request, 400, html) + self._sso_handler = hs.get_sso_handler() def _validate_metadata(self): """Verifies the provider metadata. @@ -568,7 +544,7 @@ class OidcHandler(BaseHandler): Since we might want to display OIDC-related errors in a user-friendly way, we don't raise SynapseError from here. Instead, we call - ``self._render_error`` which displays an HTML page for the error. + ``self._sso_handler.render_error`` which displays an HTML page for the error. Most of the OpenID Connect logic happens here: @@ -606,7 +582,7 @@ class OidcHandler(BaseHandler): if error != "access_denied": logger.error("Error from the OIDC provider: %s %s", error, description) - self._render_error(request, error, description) + self._sso_handler.render_error(request, error, description) return # otherwise, it is presumably a successful response. see: @@ -616,7 +592,9 @@ class OidcHandler(BaseHandler): session = request.getCookie(SESSION_COOKIE_NAME) # type: Optional[bytes] if session is None: logger.info("No session cookie found") - self._render_error(request, "missing_session", "No session cookie found") + self._sso_handler.render_error( + request, "missing_session", "No session cookie found" + ) return # Remove the cookie. There is a good chance that if the callback failed @@ -634,7 +612,9 @@ class OidcHandler(BaseHandler): # Check for the state query parameter if b"state" not in request.args: logger.info("State parameter is missing") - self._render_error(request, "invalid_request", "State parameter is missing") + self._sso_handler.render_error( + request, "invalid_request", "State parameter is missing" + ) return state = request.args[b"state"][0].decode() @@ -648,17 +628,19 @@ class OidcHandler(BaseHandler): ) = self._verify_oidc_session_token(session, state) except MacaroonDeserializationException as e: logger.exception("Invalid session") - self._render_error(request, "invalid_session", str(e)) + self._sso_handler.render_error(request, "invalid_session", str(e)) return except MacaroonInvalidSignatureException as e: logger.exception("Could not verify session") - self._render_error(request, "mismatching_session", str(e)) + self._sso_handler.render_error(request, "mismatching_session", str(e)) return # Exchange the code with the provider if b"code" not in request.args: logger.info("Code parameter is missing") - self._render_error(request, "invalid_request", "Code parameter is missing") + self._sso_handler.render_error( + request, "invalid_request", "Code parameter is missing" + ) return logger.debug("Exchanging code") @@ -667,7 +649,7 @@ class OidcHandler(BaseHandler): token = await self._exchange_code(code) except OidcError as e: logger.exception("Could not exchange code") - self._render_error(request, e.error, e.error_description) + self._sso_handler.render_error(request, e.error, e.error_description) return logger.debug("Successfully obtained OAuth2 access token") @@ -680,7 +662,7 @@ class OidcHandler(BaseHandler): userinfo = await self._fetch_userinfo(token) except Exception as e: logger.exception("Could not fetch userinfo") - self._render_error(request, "fetch_error", str(e)) + self._sso_handler.render_error(request, "fetch_error", str(e)) return else: logger.debug("Extracting userinfo from id_token") @@ -688,7 +670,7 @@ class OidcHandler(BaseHandler): userinfo = await self._parse_id_token(token, nonce=nonce) except Exception as e: logger.exception("Invalid id_token") - self._render_error(request, "invalid_token", str(e)) + self._sso_handler.render_error(request, "invalid_token", str(e)) return # Pull out the user-agent and IP from the request. @@ -702,7 +684,7 @@ class OidcHandler(BaseHandler): ) except MappingException as e: logger.exception("Could not map user") - self._render_error(request, "mapping_error", str(e)) + self._sso_handler.render_error(request, "mapping_error", str(e)) return # Mapping providers might not have get_extra_attributes: only call this diff --git a/synapse/handlers/saml_handler.py b/synapse/handlers/saml_handler.py index 6929c7ca10..e702137903 100644 --- a/synapse/handlers/saml_handler.py +++ b/synapse/handlers/saml_handler.py @@ -25,7 +25,7 @@ from synapse.api.errors import SynapseError from synapse.config import ConfigError from synapse.config.saml2_config import SamlAttributeRequirement from synapse.handlers._base import BaseHandler -from synapse.http.server import respond_with_html +from synapse.handlers.sso import MappingException from synapse.http.servlet import parse_string from synapse.http.site import SynapseRequest from synapse.module_api import ModuleApi @@ -43,10 +43,6 @@ if TYPE_CHECKING: logger = logging.getLogger(__name__) -class MappingException(Exception): - """Used to catch errors when mapping the SAML2 response to a user.""" - - @attr.s(slots=True) class Saml2SessionData: """Data we track about SAML2 sessions""" @@ -87,24 +83,7 @@ class SamlHandler(BaseHandler): # a lock on the mappings self._mapping_lock = Linearizer(name="saml_mapping", clock=self.clock) - def _render_error( - self, request, error: str, error_description: Optional[str] = None - ) -> None: - """Render the error template and respond to the request with it. - - This is used to show errors to the user. The template of this page can - be found under `synapse/res/templates/sso_error.html`. - - Args: - request: The incoming request from the browser. - We'll respond with an HTML page describing the error. - error: A technical identifier for this error. - error_description: A human-readable description of the error. - """ - html = self._error_template.render( - error=error, error_description=error_description - ) - respond_with_html(request, 400, html) + self._sso_handler = hs.get_sso_handler() def handle_redirect_request( self, client_redirect_url: bytes, ui_auth_session_id: Optional[str] = None @@ -168,12 +147,12 @@ class SamlHandler(BaseHandler): # in the (user-visible) exception message, so let's log the exception here # so we can track down the session IDs later. logger.warning(str(e)) - self._render_error( + self._sso_handler.render_error( request, "unsolicited_response", "Unexpected SAML2 login." ) return except Exception as e: - self._render_error( + self._sso_handler.render_error( request, "invalid_response", "Unable to parse SAML2 response: %s." % (e,), @@ -181,7 +160,7 @@ class SamlHandler(BaseHandler): return if saml2_auth.not_signed: - self._render_error( + self._sso_handler.render_error( request, "unsigned_respond", "SAML2 response was not signed." ) return @@ -207,7 +186,7 @@ class SamlHandler(BaseHandler): # attributes. for requirement in self._saml2_attribute_requirements: if not _check_attribute_requirement(saml2_auth.ava, requirement): - self._render_error( + self._sso_handler.render_error( request, "unauthorised", "You are not authorised to log in here." ) return @@ -223,7 +202,7 @@ class SamlHandler(BaseHandler): ) except MappingException as e: logger.exception("Could not map user") - self._render_error(request, "mapping_error", str(e)) + self._sso_handler.render_error(request, "mapping_error", str(e)) return # Complete the interactive auth session or the login. diff --git a/synapse/handlers/sso.py b/synapse/handlers/sso.py new file mode 100644 index 0000000000..3e6dc8b15b --- /dev/null +++ b/synapse/handlers/sso.py @@ -0,0 +1,54 @@ +# -*- 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. +import logging +from typing import TYPE_CHECKING, Optional + +from synapse.handlers._base import BaseHandler +from synapse.http.server import respond_with_html + +if TYPE_CHECKING: + from synapse.server import HomeServer + +logger = logging.getLogger(__name__) + + +class MappingException(Exception): + """Used to catch errors when mapping the UserInfo object + """ + + +class SsoHandler(BaseHandler): + def __init__(self, hs: "HomeServer"): + super().__init__(hs) + self._error_template = hs.config.sso_error_template + + def render_error( + self, request, error: str, error_description: Optional[str] = None + ) -> None: + """Renders the error template and respond with it. + + This is used to show errors to the user. The template of this page can + be found under ``synapse/res/templates/sso_error.html``. + + Args: + request: The incoming request from the browser. + We'll respond with an HTML page describing the error. + error: A technical identifier for this error. + error_description: A human-readable description of the error. + """ + html = self._error_template.render( + error=error, error_description=error_description + ) + respond_with_html(request, 400, html) diff --git a/synapse/server.py b/synapse/server.py index 21a232bbd9..d7e0c6e3bf 100644 --- a/synapse/server.py +++ b/synapse/server.py @@ -89,6 +89,7 @@ from synapse.handlers.room_member import RoomMemberMasterHandler from synapse.handlers.room_member_worker import RoomMemberWorkerHandler from synapse.handlers.search import SearchHandler from synapse.handlers.set_password import SetPasswordHandler +from synapse.handlers.sso import SsoHandler from synapse.handlers.stats import StatsHandler from synapse.handlers.sync import SyncHandler from synapse.handlers.typing import FollowerTypingHandler, TypingWriterHandler @@ -390,6 +391,10 @@ class HomeServer(metaclass=abc.ABCMeta): else: return FollowerTypingHandler(self) + @cache_in_self + def get_sso_handler(self): + return SsoHandler(self) + @cache_in_self def get_sync_handler(self) -> SyncHandler: return SyncHandler(self) diff --git a/tests/handlers/test_oidc.py b/tests/handlers/test_oidc.py index 0d51705849..630e6da808 100644 --- a/tests/handlers/test_oidc.py +++ b/tests/handlers/test_oidc.py @@ -154,6 +154,9 @@ class OidcHandlerTestCase(HomeserverTestCase): ) self.handler = OidcHandler(hs) + # Mock the render error method. + self.render_error = Mock(return_value=None) + self.handler._sso_handler.render_error = self.render_error return hs @@ -161,12 +164,12 @@ class OidcHandlerTestCase(HomeserverTestCase): return patch.dict(self.handler._provider_metadata, values) def assertRenderedError(self, error, error_description=None): - args = self.handler._render_error.call_args[0] + args = self.render_error.call_args[0] self.assertEqual(args[1], error) if error_description is not None: self.assertEqual(args[2], error_description) # Reset the render_error mock - self.handler._render_error.reset_mock() + self.render_error.reset_mock() def test_config(self): """Basic config correctly sets up the callback URL and client auth correctly.""" @@ -356,7 +359,6 @@ class OidcHandlerTestCase(HomeserverTestCase): def test_callback_error(self): """Errors from the provider returned in the callback are displayed.""" - self.handler._render_error = Mock() request = Mock(args={}) request.args[b"error"] = [b"invalid_client"] self.get_success(self.handler.handle_oidc_callback(request)) @@ -387,7 +389,6 @@ class OidcHandlerTestCase(HomeserverTestCase): "preferred_username": "bar", } user_id = "@foo:domain.org" - self.handler._render_error = Mock(return_value=None) self.handler._exchange_code = simple_async_mock(return_value=token) self.handler._parse_id_token = simple_async_mock(return_value=userinfo) self.handler._fetch_userinfo = simple_async_mock(return_value=userinfo) @@ -435,7 +436,7 @@ class OidcHandlerTestCase(HomeserverTestCase): userinfo, token, user_agent, ip_address ) self.handler._fetch_userinfo.assert_not_called() - self.handler._render_error.assert_not_called() + self.render_error.assert_not_called() # Handle mapping errors self.handler._map_userinfo_to_user = simple_async_mock( @@ -469,7 +470,7 @@ class OidcHandlerTestCase(HomeserverTestCase): userinfo, token, user_agent, ip_address ) self.handler._fetch_userinfo.assert_called_once_with(token) - self.handler._render_error.assert_not_called() + self.render_error.assert_not_called() # Handle userinfo fetching error self.handler._fetch_userinfo = simple_async_mock(raises=Exception()) @@ -485,7 +486,6 @@ class OidcHandlerTestCase(HomeserverTestCase): def test_callback_session(self): """The callback verifies the session presence and validity""" - self.handler._render_error = Mock(return_value=None) request = Mock(spec=["args", "getCookie", "addCookie"]) # Missing cookie