providers/oauth2: fix null amr value not being removed from id_token

closes #4339

Signed-off-by: Jens Langhammer <jens.langhammer@beryju.org>

authentik/events/signals.py

@@ -39,6 +39,11 @@ def on_user_logged_in(sender, request: HttpRequest, user: User, **_):
     request.session[SESSION_LOGIN_EVENT] = event
 
 
+def get_login_event(request: HttpRequest) -> Optional[Event]:
+    """Wrapper to get login event that can be mocked in tests"""
+    return request.session.get(SESSION_LOGIN_EVENT, None)
+
+
 @receiver(user_logged_out)
 # pylint: disable=unused-argument
 def on_user_logged_out(sender, request: HttpRequest, user: User, **_):

authentik/providers/oauth2/models.py

@@ -22,8 +22,7 @@ from rest_framework.serializers import Serializer
 
 from authentik.core.models import ExpiringModel, PropertyMapping, Provider, User
 from authentik.crypto.models import CertificateKeyPair
-from authentik.events.models import Event
-from authentik.events.signals import SESSION_LOGIN_EVENT
+from authentik.events.signals import get_login_event
 from authentik.lib.generators import generate_code_fixed_length, generate_id, generate_key
 from authentik.lib.models import SerializerModel
 from authentik.lib.utils.time import timedelta_string_validator
@@ -419,6 +418,8 @@ class IDToken:
             id_dict.pop("nonce")
         if not self.c_hash:
             id_dict.pop("c_hash")
+        if not self.amr:
+            id_dict.pop("amr")
         id_dict.pop("claims")
         id_dict.update(self.claims)
         return id_dict
@@ -503,8 +504,8 @@ class RefreshToken(SerializerModel, ExpiringModel, BaseGrantModel):
         # We use the timestamp of the user's last successful login (EventAction.LOGIN) for auth_time
         # Fallback in case we can't find any login events
         auth_time = now
-        if SESSION_LOGIN_EVENT in request.session:
-            auth_event: Event = request.session[SESSION_LOGIN_EVENT]
+        auth_event = get_login_event(request)
+        if auth_event:
             auth_time = auth_event.created
             # Also check which method was used for authentication
             method = auth_event.context.get(PLAN_CONTEXT_METHOD, "")
@@ -526,6 +527,7 @@ class RefreshToken(SerializerModel, ExpiringModel, BaseGrantModel):
             exp=exp_time,
             iat=iat_time,
             auth_time=auth_timestamp,
+            amr=amr if amr else None,
         )
 
         # Include (or not) user standard claims in the id_token.

authentik/providers/oauth2/tests/test_authorize.py

@@ -1,10 +1,13 @@
 """Test authorize view"""
+from unittest.mock import MagicMock, patch
+
 from django.test import RequestFactory
 from django.urls import reverse
 from django.utils.timezone import now
 
 from authentik.core.models import Application
 from authentik.core.tests.utils import create_test_admin_user, create_test_flow
+from authentik.events.models import Event, EventAction
 from authentik.flows.challenge import ChallengeTypes
 from authentik.lib.generators import generate_id, generate_key
 from authentik.lib.utils.time import timedelta_from_string
@@ -17,6 +20,7 @@ from authentik.providers.oauth2.models import (
 )
 from authentik.providers.oauth2.tests.utils import OAuthTestCase
 from authentik.providers.oauth2.views.authorize import OAuthAuthorizationParams
+from authentik.stages.password.stage import PLAN_CONTEXT_METHOD
 
 
 class TestAuthorize(OAuthTestCase):
@@ -302,6 +306,16 @@ class TestAuthorize(OAuthTestCase):
         state = generate_id()
         user = create_test_admin_user()
         self.client.force_login(user)
+        with patch(
+            "authentik.providers.oauth2.models.get_login_event",
+            MagicMock(
+                return_value=Event(
+                    action=EventAction.LOGIN,
+                    context={PLAN_CONTEXT_METHOD: "password"},
+                    created=now(),
+                )
+            ),
+        ):
             # Step 1, initiate params and get redirect to flow
             self.client.get(
                 reverse("authentik_providers_oauth2:authorize"),
@@ -331,6 +345,7 @@ class TestAuthorize(OAuthTestCase):
                 },
             )
             jwt = self.validate_jwt(token, provider)
+            self.assertEqual(jwt["amr"], ["pwd"])
             self.assertAlmostEqual(
                 jwt["exp"] - now().timestamp(),
                 expires,

authentik/providers/oauth2/tests/utils.py

@@ -27,6 +27,11 @@ class OAuthTestCase(TestCase):
         cls.keypair = create_test_cert()
         super().setUpClass()
 
+    def assert_non_none_or_unset(self, container: dict, key: str):
+        """Check that a key, if set, is not none"""
+        if key in container:
+            self.assertIsNotNone(container[key])
+
     def validate_jwt(self, token: RefreshToken, provider: OAuth2Provider) -> dict[str, Any]:
         """Validate that all required fields are set"""
         key, alg = provider.jwt_key
@@ -39,6 +44,10 @@ class OAuthTestCase(TestCase):
             audience=provider.client_id,
         )
         id_token = token.id_token.to_dict()
+        self.assert_non_none_or_unset(id_token, "at_hash")
+        self.assert_non_none_or_unset(id_token, "nonce")
+        self.assert_non_none_or_unset(id_token, "c_hash")
+        self.assert_non_none_or_unset(id_token, "amr")
         for key in self.required_jwt_keys:
             self.assertIsNotNone(jwt[key], f"Key {key} is missing in access_token")
             self.assertIsNotNone(id_token[key], f"Key {key} is missing in id_token")

authentik/providers/saml/processors/assertion.py

@@ -10,7 +10,7 @@ from structlog.stdlib import get_logger
 
 from authentik.core.exceptions import PropertyMappingExpressionException
 from authentik.events.models import Event, EventAction
-from authentik.events.signals import SESSION_LOGIN_EVENT
+from authentik.events.signals import get_login_event
 from authentik.lib.utils.time import timedelta_from_string
 from authentik.providers.saml.models import SAMLPropertyMapping, SAMLProvider
 from authentik.providers.saml.processors.request_parser import AuthNRequest
@@ -132,8 +132,8 @@ class AssertionProcessor:
             auth_n_context, f"{{{NS_SAML_ASSERTION}}}AuthnContextClassRef"
         )
         auth_n_context_class_ref.text = "urn:oasis:names:tc:SAML:2.0:ac:classes:unspecified"
-        if SESSION_LOGIN_EVENT in self.http_request.session:
-            event: Event = self.http_request.session[SESSION_LOGIN_EVENT]
+        event = get_login_event(self.http_request)
+        if event:
             method = event.context.get(PLAN_CONTEXT_METHOD, "")
             method_args = event.context.get(PLAN_CONTEXT_METHOD_ARGS, {})
             if method == "password":