From 79bfe966e08a2212cc2fae2b00f5efb2c2185543 Mon Sep 17 00:00:00 2001 From: Patrick Cloke Date: Thu, 19 Nov 2020 14:25:17 -0500 Subject: Improve error checking for OIDC/SAML mapping providers (#8774) Checks that the localpart returned by mapping providers for SAML and OIDC are valid before registering new users. Extends the OIDC tests for existing users and invalid data. --- synapse/handlers/oidc_handler.py | 25 ++++++++++++++++++++----- synapse/handlers/saml_handler.py | 6 ++++++ 2 files changed, 26 insertions(+), 5 deletions(-) (limited to 'synapse/handlers') diff --git a/synapse/handlers/oidc_handler.py b/synapse/handlers/oidc_handler.py index be8562d47b..4bfd8d5617 100644 --- a/synapse/handlers/oidc_handler.py +++ b/synapse/handlers/oidc_handler.py @@ -38,7 +38,12 @@ from synapse.handlers._base import BaseHandler 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 +from synapse.types import ( + JsonDict, + UserID, + contains_invalid_mxid_characters, + map_username_to_mxid_localpart, +) from synapse.util import json_decoder if TYPE_CHECKING: @@ -885,10 +890,12 @@ class OidcHandler(BaseHandler): "Retrieved user attributes from user mapping provider: %r", attributes ) - if not attributes["localpart"]: - raise MappingException("localpart is empty") - - localpart = map_username_to_mxid_localpart(attributes["localpart"]) + localpart = attributes["localpart"] + if not localpart: + raise MappingException( + "Error parsing OIDC response: OIDC mapping provider plugin " + "did not return a localpart value" + ) user_id = UserID(localpart, self.server_name).to_string() users = await self.store.get_users_by_id_case_insensitive(user_id) @@ -908,6 +915,11 @@ class OidcHandler(BaseHandler): # This mxid is taken raise MappingException("mxid '{}' is already taken".format(user_id)) else: + # Since the localpart is provided via a potentially untrusted module, + # ensure the MXID is valid before registering. + if contains_invalid_mxid_characters(localpart): + raise MappingException("localpart is invalid: %s" % (localpart,)) + # It's the first time this user is logging in and the mapped mxid was # not taken, register the user registered_user_id = await self._registration_handler.register_user( @@ -1076,6 +1088,9 @@ class JinjaOidcMappingProvider(OidcMappingProvider[JinjaOidcMappingConfig]): ) -> UserAttribute: localpart = self._config.localpart_template.render(user=userinfo).strip() + # Ensure only valid characters are included in the MXID. + localpart = map_username_to_mxid_localpart(localpart) + display_name = None # type: Optional[str] if self._config.display_name_template is not None: display_name = self._config.display_name_template.render( diff --git a/synapse/handlers/saml_handler.py b/synapse/handlers/saml_handler.py index 9bf430b656..5d9b555b13 100644 --- a/synapse/handlers/saml_handler.py +++ b/synapse/handlers/saml_handler.py @@ -31,6 +31,7 @@ from synapse.http.site import SynapseRequest from synapse.module_api import ModuleApi from synapse.types import ( UserID, + contains_invalid_mxid_characters, map_username_to_mxid_localpart, mxid_localpart_allowed_characters, ) @@ -318,6 +319,11 @@ class SamlHandler(BaseHandler): "Unable to generate a Matrix ID from the SAML response" ) + # Since the localpart is provided via a potentially untrusted module, + # ensure the MXID is valid before registering. + if contains_invalid_mxid_characters(localpart): + raise MappingException("localpart is invalid: %s" % (localpart,)) + logger.info("Mapped SAML user to local part %s", localpart) registered_user_id = await self._registration_handler.register_user( localpart=localpart, -- cgit 1.4.1