Add regression test for broken ClientProtectedResourceMixin

aleksis/core/tests/regression/test_regression.py

+import base64
+
 from django.contrib.auth import get_user_model
 
 import pytest
 
-from aleksis.core.models import Group, Person
+from aleksis.core.models import Group, OAuthApplication, Person
 
 pytestmark = pytest.mark.django_db
+from django.http import HttpResponse
+from django.test import override_settings
+from django.urls import path, reverse
+from django.views.generic import View
 
 
 def test_all_settigns_registered():
@@ -82,3 +88,61 @@ def test_reassign_user_to_person():
     assert user2.groups.count() == 1
     assert user1.groups.first().name == "Group 2"
     assert user2.groups.first().name == "Group 1"
+
+
+@override_settings(ROOT_URLCONF="aleksis.core.tests.regression.view_oauth")
+def test_no_access_oauth2_client_credentials_without_allowed_scopes(client):
+    """Tests that ClientProtectedResourceMixin doesn't allow access if no allowed scopes are set.
+
+    https://edugit.org/AlekSIS/official/AlekSIS-Core/-/issues/688
+    """
+
+    wrong_application = OAuthApplication.objects.create(
+        name="Test Application",
+        allowed_scopes=[],
+        authorization_grant_type=OAuthApplication.GRANT_CLIENT_CREDENTIALS,
+        client_type=OAuthApplication.CLIENT_CONFIDENTIAL,
+        redirect_uris=["http://localhost:8000/"],
+    )
+    wrong_application_2 = OAuthApplication.objects.create(
+        name="Test Application",
+        allowed_scopes=["read"],
+        authorization_grant_type=OAuthApplication.GRANT_CLIENT_CREDENTIALS,
+        client_type=OAuthApplication.CLIENT_CONFIDENTIAL,
+        redirect_uris=["http://localhost:8000/"],
+    )
+    correct_application = OAuthApplication.objects.create(
+        name="Test Application",
+        allowed_scopes=["write"],
+        authorization_grant_type=OAuthApplication.GRANT_CLIENT_CREDENTIALS,
+        client_type=OAuthApplication.CLIENT_CONFIDENTIAL,
+        redirect_uris=["http://localhost:8000/"],
+    )
+
+    url = reverse("client_protected_resource_mixin_test")
+    auth_header = (
+        "Basic "
+        + base64.b64encode(
+            f"{wrong_application.client_id}:{wrong_application.client_secret}".encode()
+        ).decode()
+    )
+    r = client.get(url, HTTP_AUTHORIZATION=auth_header)
+    assert r.status_code == 403
+
+    auth_header = (
+        "Basic "
+        + base64.b64encode(
+            f"{wrong_application_2.client_id}:{wrong_application_2.client_secret}".encode()
+        ).decode()
+    )
+    r = client.get(url, HTTP_AUTHORIZATION=auth_header)
+    assert r.status_code == 403
+
+    auth_header = (
+        "Basic "
+        + base64.b64encode(
+            f"{correct_application.client_id}:{correct_application.client_secret}".encode()
+        ).decode()
+    )
+    r = client.get(url, HTTP_AUTHORIZATION=auth_header)
+    assert r.status_code == 200

aleksis/core/tests/regression/view_oauth.py

+from django.http import HttpResponse
+from django.test import override_settings
+from django.urls import path, reverse
+from django.views.generic import View
+
+from oauth2_provider.views.mixins import ScopedResourceMixin
+
+from aleksis.core.util.auth_helpers import ClientProtectedResourceMixin
+
+
+class TestViewClientProtectedResourceMixin(ScopedResourceMixin, ClientProtectedResourceMixin, View):
+    required_scopes = ["write"]
+
+    def get(self, request):
+        return HttpResponse("OK")
+
+
+urlpatterns = [
+    path(
+        "client_protected_resource_mixin_test/",
+        TestViewClientProtectedResourceMixin.as_view(),
+        name="client_protected_resource_mixin_test",
+    ),
+]