From c7401a697f1ee3410b860afd8686f8bb012a8dce Mon Sep 17 00:00:00 2001 From: Richard van der Hoff <1389908+richvdh@users.noreply.github.com> Date: Fri, 7 Dec 2018 13:11:11 +0100 Subject: [PATCH] Implement SAML2 authentication (#4267) This implements both a SAML2 metadata endpoint (at `/_matrix/saml2/metadata.xml`), and a SAML2 response receiver (at `/_matrix/saml2/authn_response`). If the SAML2 response matches what's been configured, we complete the SSO login flow by redirecting to the client url (aka `RelayState` in SAML2 jargon) with a login token. What we don't yet have is anything to build a SAML2 request and redirect the user to the identity provider. That is left as an exercise for the reader. --- changelog.d/4267.feature | 1 + synapse/app/homeserver.py | 4 + synapse/config/homeserver.py | 3 +- synapse/config/saml2_config.py | 110 ++++++++++++++++++++++++ synapse/python_dependencies.py | 5 +- synapse/rest/saml2/__init__.py | 29 +++++++ synapse/rest/saml2/metadata_resource.py | 36 ++++++++ synapse/rest/saml2/response_resource.py | 71 +++++++++++++++ tests/utils.py | 1 + 9 files changed, 258 insertions(+), 2 deletions(-) create mode 100644 changelog.d/4267.feature create mode 100644 synapse/config/saml2_config.py create mode 100644 synapse/rest/saml2/__init__.py create mode 100644 synapse/rest/saml2/metadata_resource.py create mode 100644 synapse/rest/saml2/response_resource.py diff --git a/changelog.d/4267.feature b/changelog.d/4267.feature new file mode 100644 index 000000000..da36986e2 --- /dev/null +++ b/changelog.d/4267.feature @@ -0,0 +1 @@ +Rework SAML2 authentication diff --git a/synapse/app/homeserver.py b/synapse/app/homeserver.py index a03a3e4b8..1e495a38b 100755 --- a/synapse/app/homeserver.py +++ b/synapse/app/homeserver.py @@ -199,6 +199,10 @@ class SynapseHomeServer(HomeServer): "/.well-known/matrix/client": WellKnownResource(self), }) + if self.get_config().saml2_enabled: + from synapse.rest.saml2 import SAML2Resource + resources["/_matrix/saml2"] = SAML2Resource(self) + if name == "consent": from synapse.rest.consent.consent_resource import ConsentResource consent_resource = ConsentResource(self) diff --git a/synapse/config/homeserver.py b/synapse/config/homeserver.py index 36182267c..9d740c7a7 100644 --- a/synapse/config/homeserver.py +++ b/synapse/config/homeserver.py @@ -32,6 +32,7 @@ from .ratelimiting import RatelimitConfig from .registration import RegistrationConfig from .repository import ContentRepositoryConfig from .room_directory import RoomDirectoryConfig +from .saml2_config import SAML2Config from .server import ServerConfig from .server_notices_config import ServerNoticesConfig from .spam_checker import SpamCheckerConfig @@ -44,7 +45,7 @@ from .workers import WorkerConfig class HomeServerConfig(TlsConfig, ServerConfig, DatabaseConfig, LoggingConfig, RatelimitConfig, ContentRepositoryConfig, CaptchaConfig, VoipConfig, RegistrationConfig, MetricsConfig, ApiConfig, - AppServiceConfig, KeyConfig, CasConfig, + AppServiceConfig, KeyConfig, SAML2Config, CasConfig, JWTConfig, PasswordConfig, EmailConfig, WorkerConfig, PasswordAuthProviderConfig, PushConfig, SpamCheckerConfig, GroupsConfig, UserDirectoryConfig, diff --git a/synapse/config/saml2_config.py b/synapse/config/saml2_config.py new file mode 100644 index 000000000..86ffe334f --- /dev/null +++ b/synapse/config/saml2_config.py @@ -0,0 +1,110 @@ +# -*- coding: utf-8 -*- +# Copyright 2018 New Vector Ltd. +# +# 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 ._base import Config, ConfigError + + +class SAML2Config(Config): + def read_config(self, config): + self.saml2_enabled = False + + saml2_config = config.get("saml2_config") + + if not saml2_config or not saml2_config.get("enabled", True): + return + + self.saml2_enabled = True + + import saml2.config + self.saml2_sp_config = saml2.config.SPConfig() + self.saml2_sp_config.load(self._default_saml_config_dict()) + self.saml2_sp_config.load(saml2_config.get("sp_config", {})) + + config_path = saml2_config.get("config_path", None) + if config_path is not None: + self.saml2_sp_config.load_file(config_path) + + def _default_saml_config_dict(self): + import saml2 + + public_baseurl = self.public_baseurl + if public_baseurl is None: + raise ConfigError( + "saml2_config requires a public_baseurl to be set" + ) + + metadata_url = public_baseurl + "_matrix/saml2/metadata.xml" + response_url = public_baseurl + "_matrix/saml2/authn_response" + return { + "entityid": metadata_url, + + "service": { + "sp": { + "endpoints": { + "assertion_consumer_service": [ + (response_url, saml2.BINDING_HTTP_POST), + ], + }, + "required_attributes": ["uid"], + "optional_attributes": ["mail", "surname", "givenname"], + }, + } + } + + def default_config(self, config_dir_path, server_name, **kwargs): + return """ + # Enable SAML2 for registration and login. Uses pysaml2. + # + # saml2_config: + # + # # The following is the configuration for the pysaml2 Service Provider. + # # See pysaml2 docs for format of config. + # # + # # Default values will be used for the 'entityid' and 'service' settings, + # # so it is not normally necessary to specify them unless you need to + # # override them. + # + # sp_config: + # # point this to the IdP's metadata. You can use either a local file or + # # (preferably) a URL. + # metadata: + # # local: ["saml2/idp.xml"] + # remote: + # - url: https://our_idp/metadata.xml + # + # # The following is just used to generate our metadata xml, and you + # # may well not need it, depending on your setup. Alternatively you + # # may need a whole lot more detail - see the pysaml2 docs! + # + # description: ["My awesome SP", "en"] + # name: ["Test SP", "en"] + # + # organization: + # name: Example com + # display_name: + # - ["Example co", "en"] + # url: "http://example.com" + # + # contact_person: + # - given_name: Bob + # sur_name: "the Sysadmin" + # email_address": ["admin@example.com"] + # contact_type": technical + # + # # Instead of putting the config inline as above, you can specify a + # # separate pysaml2 configuration file: + # # + # # config_path: "%(config_dir_path)s/sp_conf.py" + """ % {"config_dir_path": config_dir_path} diff --git a/synapse/python_dependencies.py b/synapse/python_dependencies.py index 75ba9947c..db631e0c6 100644 --- a/synapse/python_dependencies.py +++ b/synapse/python_dependencies.py @@ -80,7 +80,10 @@ CONDITIONAL_REQUIREMENTS = { }, "postgres": { "psycopg2>=2.6": ["psycopg2"] - } + }, + "saml2": { + "pysaml2>=4.5.0": ["saml2"], + }, } diff --git a/synapse/rest/saml2/__init__.py b/synapse/rest/saml2/__init__.py new file mode 100644 index 000000000..68da37ca6 --- /dev/null +++ b/synapse/rest/saml2/__init__.py @@ -0,0 +1,29 @@ +# -*- coding: utf-8 -*- +# Copyright 2018 New Vector Ltd +# +# 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 twisted.web.resource import Resource + +from synapse.rest.saml2.metadata_resource import SAML2MetadataResource +from synapse.rest.saml2.response_resource import SAML2ResponseResource + +logger = logging.getLogger(__name__) + + +class SAML2Resource(Resource): + def __init__(self, hs): + Resource.__init__(self) + self.putChild(b"metadata.xml", SAML2MetadataResource(hs)) + self.putChild(b"authn_response", SAML2ResponseResource(hs)) diff --git a/synapse/rest/saml2/metadata_resource.py b/synapse/rest/saml2/metadata_resource.py new file mode 100644 index 000000000..e8c680aeb --- /dev/null +++ b/synapse/rest/saml2/metadata_resource.py @@ -0,0 +1,36 @@ +# -*- coding: utf-8 -*- +# Copyright 2018 New Vector Ltd +# +# 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 saml2.metadata + +from twisted.web.resource import Resource + + +class SAML2MetadataResource(Resource): + """A Twisted web resource which renders the SAML metadata""" + + isLeaf = 1 + + def __init__(self, hs): + Resource.__init__(self) + self.sp_config = hs.config.saml2_sp_config + + def render_GET(self, request): + metadata_xml = saml2.metadata.create_metadata_string( + configfile=None, config=self.sp_config, + ) + request.setHeader(b"Content-Type", b"text/xml; charset=utf-8") + return metadata_xml diff --git a/synapse/rest/saml2/response_resource.py b/synapse/rest/saml2/response_resource.py new file mode 100644 index 000000000..ad2ed157b --- /dev/null +++ b/synapse/rest/saml2/response_resource.py @@ -0,0 +1,71 @@ +# -*- coding: utf-8 -*- +# +# Copyright 2018 New Vector Ltd +# +# 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 + +import saml2 +from saml2.client import Saml2Client + +from twisted.web.resource import Resource +from twisted.web.server import NOT_DONE_YET + +from synapse.api.errors import CodeMessageException +from synapse.http.server import wrap_html_request_handler +from synapse.http.servlet import parse_string +from synapse.rest.client.v1.login import SSOAuthHandler + +logger = logging.getLogger(__name__) + + +class SAML2ResponseResource(Resource): + """A Twisted web resource which handles the SAML response""" + + isLeaf = 1 + + def __init__(self, hs): + Resource.__init__(self) + + self._saml_client = Saml2Client(hs.config.saml2_sp_config) + self._sso_auth_handler = SSOAuthHandler(hs) + + def render_POST(self, request): + self._async_render_POST(request) + return NOT_DONE_YET + + @wrap_html_request_handler + def _async_render_POST(self, request): + resp_bytes = parse_string(request, 'SAMLResponse', required=True) + relay_state = parse_string(request, 'RelayState', required=True) + + try: + saml2_auth = self._saml_client.parse_authn_request_response( + resp_bytes, saml2.BINDING_HTTP_POST, + ) + except Exception as e: + logger.warning("Exception parsing SAML2 response", exc_info=1) + raise CodeMessageException( + 400, "Unable to parse SAML2 response: %s" % (e,), + ) + + if saml2_auth.not_signed: + raise CodeMessageException(400, "SAML2 response was not signed") + + if "uid" not in saml2_auth.ava: + raise CodeMessageException(400, "uid not in SAML2 response") + + username = saml2_auth.ava["uid"][0] + return self._sso_auth_handler.on_successful_auth( + username, request, relay_state, + ) diff --git a/tests/utils.py b/tests/utils.py index 52ab76201..04796a9b3 100644 --- a/tests/utils.py +++ b/tests/utils.py @@ -139,6 +139,7 @@ def default_config(name): config.admin_contact = None config.rc_messages_per_second = 10000 config.rc_message_burst_count = 10000 + config.saml2_enabled = False config.use_frozen_dicts = False