forked-synapse/tests/handlers/test_oidc.py
2020-05-08 08:30:40 -04:00

566 lines
23 KiB
Python

# -*- coding: utf-8 -*-
# Copyright 2020 Quentin Gliech
#
# 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 json
from urllib.parse import parse_qs, urlparse
from mock import Mock, patch
import attr
import pymacaroons
from twisted.internet import defer
from twisted.python.failure import Failure
from twisted.web._newclient import ResponseDone
from synapse.handlers.oidc_handler import (
MappingException,
OidcError,
OidcHandler,
OidcMappingProvider,
)
from synapse.types import UserID
from tests.unittest import HomeserverTestCase, override_config
@attr.s
class FakeResponse:
code = attr.ib()
body = attr.ib()
phrase = attr.ib()
def deliverBody(self, protocol):
protocol.dataReceived(self.body)
protocol.connectionLost(Failure(ResponseDone()))
# These are a few constants that are used as config parameters in the tests.
ISSUER = "https://issuer/"
CLIENT_ID = "test-client-id"
CLIENT_SECRET = "test-client-secret"
BASE_URL = "https://synapse/"
CALLBACK_URL = BASE_URL + "_synapse/oidc/callback"
SCOPES = ["openid"]
AUTHORIZATION_ENDPOINT = ISSUER + "authorize"
TOKEN_ENDPOINT = ISSUER + "token"
USERINFO_ENDPOINT = ISSUER + "userinfo"
WELL_KNOWN = ISSUER + ".well-known/openid-configuration"
JWKS_URI = ISSUER + ".well-known/jwks.json"
# config for common cases
COMMON_CONFIG = {
"discover": False,
"authorization_endpoint": AUTHORIZATION_ENDPOINT,
"token_endpoint": TOKEN_ENDPOINT,
"jwks_uri": JWKS_URI,
}
# The cookie name and path don't really matter, just that it has to be coherent
# between the callback & redirect handlers.
COOKIE_NAME = b"oidc_session"
COOKIE_PATH = "/_synapse/oidc"
MockedMappingProvider = Mock(OidcMappingProvider)
def simple_async_mock(return_value=None, raises=None):
# AsyncMock is not available in python3.5, this mimics part of its behaviour
async def cb(*args, **kwargs):
if raises:
raise raises
return return_value
return Mock(side_effect=cb)
async def get_json(url):
# Mock get_json calls to handle jwks & oidc discovery endpoints
if url == WELL_KNOWN:
# Minimal discovery document, as defined in OpenID.Discovery
# https://openid.net/specs/openid-connect-discovery-1_0.html#ProviderMetadata
return {
"issuer": ISSUER,
"authorization_endpoint": AUTHORIZATION_ENDPOINT,
"token_endpoint": TOKEN_ENDPOINT,
"jwks_uri": JWKS_URI,
"userinfo_endpoint": USERINFO_ENDPOINT,
"response_types_supported": ["code"],
"subject_types_supported": ["public"],
"id_token_signing_alg_values_supported": ["RS256"],
}
elif url == JWKS_URI:
return {"keys": []}
class OidcHandlerTestCase(HomeserverTestCase):
def make_homeserver(self, reactor, clock):
self.http_client = Mock(spec=["get_json"])
self.http_client.get_json.side_effect = get_json
self.http_client.user_agent = "Synapse Test"
config = self.default_config()
config["public_baseurl"] = BASE_URL
oidc_config = config.get("oidc_config", {})
oidc_config["enabled"] = True
oidc_config["client_id"] = CLIENT_ID
oidc_config["client_secret"] = CLIENT_SECRET
oidc_config["issuer"] = ISSUER
oidc_config["scopes"] = SCOPES
oidc_config["user_mapping_provider"] = {
"module": __name__ + ".MockedMappingProvider"
}
config["oidc_config"] = oidc_config
hs = self.setup_test_homeserver(
http_client=self.http_client,
proxied_http_client=self.http_client,
config=config,
)
self.handler = OidcHandler(hs)
return hs
def metadata_edit(self, values):
return patch.dict(self.handler._provider_metadata, values)
def assertRenderedError(self, error, error_description=None):
args = self.handler._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()
def test_config(self):
"""Basic config correctly sets up the callback URL and client auth correctly."""
self.assertEqual(self.handler._callback_url, CALLBACK_URL)
self.assertEqual(self.handler._client_auth.client_id, CLIENT_ID)
self.assertEqual(self.handler._client_auth.client_secret, CLIENT_SECRET)
@override_config({"oidc_config": {"discover": True}})
@defer.inlineCallbacks
def test_discovery(self):
"""The handler should discover the endpoints from OIDC discovery document."""
# This would throw if some metadata were invalid
metadata = yield defer.ensureDeferred(self.handler.load_metadata())
self.http_client.get_json.assert_called_once_with(WELL_KNOWN)
self.assertEqual(metadata.issuer, ISSUER)
self.assertEqual(metadata.authorization_endpoint, AUTHORIZATION_ENDPOINT)
self.assertEqual(metadata.token_endpoint, TOKEN_ENDPOINT)
self.assertEqual(metadata.jwks_uri, JWKS_URI)
# FIXME: it seems like authlib does not have that defined in its metadata models
# self.assertEqual(metadata.userinfo_endpoint, USERINFO_ENDPOINT)
# subsequent calls should be cached
self.http_client.reset_mock()
yield defer.ensureDeferred(self.handler.load_metadata())
self.http_client.get_json.assert_not_called()
@override_config({"oidc_config": COMMON_CONFIG})
@defer.inlineCallbacks
def test_no_discovery(self):
"""When discovery is disabled, it should not try to load from discovery document."""
yield defer.ensureDeferred(self.handler.load_metadata())
self.http_client.get_json.assert_not_called()
@override_config({"oidc_config": COMMON_CONFIG})
@defer.inlineCallbacks
def test_load_jwks(self):
"""JWKS loading is done once (then cached) if used."""
jwks = yield defer.ensureDeferred(self.handler.load_jwks())
self.http_client.get_json.assert_called_once_with(JWKS_URI)
self.assertEqual(jwks, {"keys": []})
# subsequent calls should be cached…
self.http_client.reset_mock()
yield defer.ensureDeferred(self.handler.load_jwks())
self.http_client.get_json.assert_not_called()
# …unless forced
self.http_client.reset_mock()
yield defer.ensureDeferred(self.handler.load_jwks(force=True))
self.http_client.get_json.assert_called_once_with(JWKS_URI)
# Throw if the JWKS uri is missing
with self.metadata_edit({"jwks_uri": None}):
with self.assertRaises(RuntimeError):
yield defer.ensureDeferred(self.handler.load_jwks(force=True))
# Return empty key set if JWKS are not used
self.handler._scopes = [] # not asking the openid scope
self.http_client.get_json.reset_mock()
jwks = yield defer.ensureDeferred(self.handler.load_jwks(force=True))
self.http_client.get_json.assert_not_called()
self.assertEqual(jwks, {"keys": []})
@override_config({"oidc_config": COMMON_CONFIG})
def test_validate_config(self):
"""Provider metadatas are extensively validated."""
h = self.handler
# Default test config does not throw
h._validate_metadata()
with self.metadata_edit({"issuer": None}):
self.assertRaisesRegex(ValueError, "issuer", h._validate_metadata)
with self.metadata_edit({"issuer": "http://insecure/"}):
self.assertRaisesRegex(ValueError, "issuer", h._validate_metadata)
with self.metadata_edit({"issuer": "https://invalid/?because=query"}):
self.assertRaisesRegex(ValueError, "issuer", h._validate_metadata)
with self.metadata_edit({"authorization_endpoint": None}):
self.assertRaisesRegex(
ValueError, "authorization_endpoint", h._validate_metadata
)
with self.metadata_edit({"authorization_endpoint": "http://insecure/auth"}):
self.assertRaisesRegex(
ValueError, "authorization_endpoint", h._validate_metadata
)
with self.metadata_edit({"token_endpoint": None}):
self.assertRaisesRegex(ValueError, "token_endpoint", h._validate_metadata)
with self.metadata_edit({"token_endpoint": "http://insecure/token"}):
self.assertRaisesRegex(ValueError, "token_endpoint", h._validate_metadata)
with self.metadata_edit({"jwks_uri": None}):
self.assertRaisesRegex(ValueError, "jwks_uri", h._validate_metadata)
with self.metadata_edit({"jwks_uri": "http://insecure/jwks.json"}):
self.assertRaisesRegex(ValueError, "jwks_uri", h._validate_metadata)
with self.metadata_edit({"response_types_supported": ["id_token"]}):
self.assertRaisesRegex(
ValueError, "response_types_supported", h._validate_metadata
)
with self.metadata_edit(
{"token_endpoint_auth_methods_supported": ["client_secret_basic"]}
):
# should not throw, as client_secret_basic is the default auth method
h._validate_metadata()
with self.metadata_edit(
{"token_endpoint_auth_methods_supported": ["client_secret_post"]}
):
self.assertRaisesRegex(
ValueError,
"token_endpoint_auth_methods_supported",
h._validate_metadata,
)
# Tests for configs that the userinfo endpoint
self.assertFalse(h._uses_userinfo)
h._scopes = [] # do not request the openid scope
self.assertTrue(h._uses_userinfo)
self.assertRaisesRegex(ValueError, "userinfo_endpoint", h._validate_metadata)
with self.metadata_edit(
{"userinfo_endpoint": USERINFO_ENDPOINT, "jwks_uri": None}
):
# Shouldn't raise with a valid userinfo, even without
h._validate_metadata()
@override_config({"oidc_config": {"skip_verification": True}})
def test_skip_verification(self):
"""Provider metadata validation can be disabled by config."""
with self.metadata_edit({"issuer": "http://insecure"}):
# This should not throw
self.handler._validate_metadata()
@defer.inlineCallbacks
def test_redirect_request(self):
"""The redirect request has the right arguments & generates a valid session cookie."""
req = Mock(spec=["addCookie", "redirect", "finish"])
yield defer.ensureDeferred(
self.handler.handle_redirect_request(req, b"http://client/redirect")
)
url = req.redirect.call_args[0][0]
url = urlparse(url)
auth_endpoint = urlparse(AUTHORIZATION_ENDPOINT)
self.assertEqual(url.scheme, auth_endpoint.scheme)
self.assertEqual(url.netloc, auth_endpoint.netloc)
self.assertEqual(url.path, auth_endpoint.path)
params = parse_qs(url.query)
self.assertEqual(params["redirect_uri"], [CALLBACK_URL])
self.assertEqual(params["response_type"], ["code"])
self.assertEqual(params["scope"], [" ".join(SCOPES)])
self.assertEqual(params["client_id"], [CLIENT_ID])
self.assertEqual(len(params["state"]), 1)
self.assertEqual(len(params["nonce"]), 1)
# Check what is in the cookie
# note: python3.5 mock does not have the .called_once() method
calls = req.addCookie.call_args_list
self.assertEqual(len(calls), 1) # called once
# For some reason, call.args does not work with python3.5
args = calls[0][0]
kwargs = calls[0][1]
self.assertEqual(args[0], COOKIE_NAME)
self.assertEqual(kwargs["path"], COOKIE_PATH)
cookie = args[1]
macaroon = pymacaroons.Macaroon.deserialize(cookie)
state = self.handler._get_value_from_macaroon(macaroon, "state")
nonce = self.handler._get_value_from_macaroon(macaroon, "nonce")
redirect = self.handler._get_value_from_macaroon(
macaroon, "client_redirect_url"
)
self.assertEqual(params["state"], [state])
self.assertEqual(params["nonce"], [nonce])
self.assertEqual(redirect, "http://client/redirect")
@defer.inlineCallbacks
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"]
yield defer.ensureDeferred(self.handler.handle_oidc_callback(request))
self.assertRenderedError("invalid_client", "")
request.args[b"error_description"] = [b"some description"]
yield defer.ensureDeferred(self.handler.handle_oidc_callback(request))
self.assertRenderedError("invalid_client", "some description")
@defer.inlineCallbacks
def test_callback(self):
"""Code callback works and display errors if something went wrong.
A lot of scenarios are tested here:
- when the callback works, with userinfo from ID token
- when the user mapping fails
- when ID token verification fails
- when the callback works, with userinfo fetched from the userinfo endpoint
- when the userinfo fetching fails
- when the code exchange fails
"""
token = {
"type": "bearer",
"id_token": "id_token",
"access_token": "access_token",
}
userinfo = {
"sub": "foo",
"preferred_username": "bar",
}
user_id = UserID("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)
self.handler._map_userinfo_to_user = simple_async_mock(return_value=user_id)
self.handler._auth_handler.complete_sso_login = simple_async_mock()
request = Mock(spec=["args", "getCookie", "addCookie"])
code = "code"
state = "state"
nonce = "nonce"
client_redirect_url = "http://client/redirect"
session = self.handler._generate_oidc_session_token(
state=state, nonce=nonce, client_redirect_url=client_redirect_url,
)
request.getCookie.return_value = session
request.args = {}
request.args[b"code"] = [code.encode("utf-8")]
request.args[b"state"] = [state.encode("utf-8")]
yield defer.ensureDeferred(self.handler.handle_oidc_callback(request))
self.handler._auth_handler.complete_sso_login.assert_called_once_with(
user_id, request, client_redirect_url,
)
self.handler._exchange_code.assert_called_once_with(code)
self.handler._parse_id_token.assert_called_once_with(token, nonce=nonce)
self.handler._map_userinfo_to_user.assert_called_once_with(userinfo, token)
self.handler._fetch_userinfo.assert_not_called()
self.handler._render_error.assert_not_called()
# Handle mapping errors
self.handler._map_userinfo_to_user = simple_async_mock(
raises=MappingException()
)
yield defer.ensureDeferred(self.handler.handle_oidc_callback(request))
self.assertRenderedError("mapping_error")
self.handler._map_userinfo_to_user = simple_async_mock(return_value=user_id)
# Handle ID token errors
self.handler._parse_id_token = simple_async_mock(raises=Exception())
yield defer.ensureDeferred(self.handler.handle_oidc_callback(request))
self.assertRenderedError("invalid_token")
self.handler._auth_handler.complete_sso_login.reset_mock()
self.handler._exchange_code.reset_mock()
self.handler._parse_id_token.reset_mock()
self.handler._map_userinfo_to_user.reset_mock()
self.handler._fetch_userinfo.reset_mock()
# With userinfo fetching
self.handler._scopes = [] # do not ask the "openid" scope
yield defer.ensureDeferred(self.handler.handle_oidc_callback(request))
self.handler._auth_handler.complete_sso_login.assert_called_once_with(
user_id, request, client_redirect_url,
)
self.handler._exchange_code.assert_called_once_with(code)
self.handler._parse_id_token.assert_not_called()
self.handler._map_userinfo_to_user.assert_called_once_with(userinfo, token)
self.handler._fetch_userinfo.assert_called_once_with(token)
self.handler._render_error.assert_not_called()
# Handle userinfo fetching error
self.handler._fetch_userinfo = simple_async_mock(raises=Exception())
yield defer.ensureDeferred(self.handler.handle_oidc_callback(request))
self.assertRenderedError("fetch_error")
# Handle code exchange failure
self.handler._exchange_code = simple_async_mock(
raises=OidcError("invalid_request")
)
yield defer.ensureDeferred(self.handler.handle_oidc_callback(request))
self.assertRenderedError("invalid_request")
@defer.inlineCallbacks
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
request.args = {}
request.getCookie.return_value = None
yield defer.ensureDeferred(self.handler.handle_oidc_callback(request))
self.assertRenderedError("missing_session", "No session cookie found")
# Missing session parameter
request.args = {}
request.getCookie.return_value = "session"
yield defer.ensureDeferred(self.handler.handle_oidc_callback(request))
self.assertRenderedError("invalid_request", "State parameter is missing")
# Invalid cookie
request.args = {}
request.args[b"state"] = [b"state"]
request.getCookie.return_value = "session"
yield defer.ensureDeferred(self.handler.handle_oidc_callback(request))
self.assertRenderedError("invalid_session")
# Mismatching session
session = self.handler._generate_oidc_session_token(
state="state", nonce="nonce", client_redirect_url="http://client/redirect",
)
request.args = {}
request.args[b"state"] = [b"mismatching state"]
request.getCookie.return_value = session
yield defer.ensureDeferred(self.handler.handle_oidc_callback(request))
self.assertRenderedError("mismatching_session")
# Valid session
request.args = {}
request.args[b"state"] = [b"state"]
request.getCookie.return_value = session
yield defer.ensureDeferred(self.handler.handle_oidc_callback(request))
self.assertRenderedError("invalid_request")
@override_config({"oidc_config": {"client_auth_method": "client_secret_post"}})
@defer.inlineCallbacks
def test_exchange_code(self):
"""Code exchange behaves correctly and handles various error scenarios."""
token = {"type": "bearer"}
token_json = json.dumps(token).encode("utf-8")
self.http_client.request = simple_async_mock(
return_value=FakeResponse(code=200, phrase=b"OK", body=token_json)
)
code = "code"
ret = yield defer.ensureDeferred(self.handler._exchange_code(code))
kwargs = self.http_client.request.call_args[1]
self.assertEqual(ret, token)
self.assertEqual(kwargs["method"], "POST")
self.assertEqual(kwargs["uri"], TOKEN_ENDPOINT)
args = parse_qs(kwargs["data"].decode("utf-8"))
self.assertEqual(args["grant_type"], ["authorization_code"])
self.assertEqual(args["code"], [code])
self.assertEqual(args["client_id"], [CLIENT_ID])
self.assertEqual(args["client_secret"], [CLIENT_SECRET])
self.assertEqual(args["redirect_uri"], [CALLBACK_URL])
# Test error handling
self.http_client.request = simple_async_mock(
return_value=FakeResponse(
code=400,
phrase=b"Bad Request",
body=b'{"error": "foo", "error_description": "bar"}',
)
)
with self.assertRaises(OidcError) as exc:
yield defer.ensureDeferred(self.handler._exchange_code(code))
self.assertEqual(exc.exception.error, "foo")
self.assertEqual(exc.exception.error_description, "bar")
# Internal server error with no JSON body
self.http_client.request = simple_async_mock(
return_value=FakeResponse(
code=500, phrase=b"Internal Server Error", body=b"Not JSON",
)
)
with self.assertRaises(OidcError) as exc:
yield defer.ensureDeferred(self.handler._exchange_code(code))
self.assertEqual(exc.exception.error, "server_error")
# Internal server error with JSON body
self.http_client.request = simple_async_mock(
return_value=FakeResponse(
code=500,
phrase=b"Internal Server Error",
body=b'{"error": "internal_server_error"}',
)
)
with self.assertRaises(OidcError) as exc:
yield defer.ensureDeferred(self.handler._exchange_code(code))
self.assertEqual(exc.exception.error, "internal_server_error")
# 4xx error without "error" field
self.http_client.request = simple_async_mock(
return_value=FakeResponse(code=400, phrase=b"Bad request", body=b"{}",)
)
with self.assertRaises(OidcError) as exc:
yield defer.ensureDeferred(self.handler._exchange_code(code))
self.assertEqual(exc.exception.error, "server_error")
# 2xx error with "error" field
self.http_client.request = simple_async_mock(
return_value=FakeResponse(
code=200, phrase=b"OK", body=b'{"error": "some_error"}',
)
)
with self.assertRaises(OidcError) as exc:
yield defer.ensureDeferred(self.handler._exchange_code(code))
self.assertEqual(exc.exception.error, "some_error")