allow disabling query model and provider

Author: zszabo-rh

README.md

@@ -369,6 +369,10 @@ customization:
   disable_query_system_prompt: true
 ```
 
+### Control model/provider overrides via authorization
+
+By default, clients may specify `model` and `provider` in `/v1/query` and `/v1/streaming_query`. Override is permitted only to callers granted the `MODEL_OVERRIDE` action via the authorization rules. Requests that include `model` or `provider` without this permission are rejected with HTTP 403.
+
 ## Safety Shields
 
 A single Llama Stack configuration file can include multiple safety shields, which are utilized in agent

docs/openapi.json

@@ -786,7 +786,8 @@
                     "get_models",
                     "get_metrics",
                     "get_config",
-                    "info"
+                    "info",
+                    "model_override"
                 ],
                 "title": "Action",
                 "description": "Available actions in the system."

src/app/endpoints/query.py

@@ -35,6 +35,7 @@
     get_agent,
     get_system_prompt,
     validate_conversation_ownership,
+    validate_model_provider_override,
 )
 from utils.mcp_headers import mcp_headers_dependency, handle_mcp_headers_with_toolgroups
 from utils.transcripts import store_transcript
@@ -174,6 +175,9 @@ async def query_endpoint_handler(
     """
     check_configuration_loaded(configuration)
 
+    # Enforce RBAC: optionally disallow overriding model/provider in requests
+    validate_model_provider_override(query_request, request.state.authorized_actions)
+
     # log Llama Stack configuration, but without sensitive information
     llama_stack_config = configuration.llama_stack_configuration.model_copy()
     llama_stack_config.api_key = "********"

src/app/endpoints/streaming_query.py

@@ -33,6 +33,7 @@
 from utils.mcp_headers import mcp_headers_dependency, handle_mcp_headers_with_toolgroups
 from utils.transcripts import store_transcript
 from utils.types import TurnSummary
+from utils.endpoints import validate_model_provider_override
 
 from app.endpoints.query import (
     get_rag_toolgroups,
@@ -548,6 +549,9 @@ async def streaming_query_endpoint_handler(  # pylint: disable=too-many-locals
 
     check_configuration_loaded(configuration)
 
+    # Enforce RBAC: optionally disallow overriding model/provider in requests
+    validate_model_provider_override(query_request, request.state.authorized_actions)
+
     # log Llama Stack configuration, but without sensitive information
     llama_stack_config = configuration.llama_stack_configuration.model_copy()
     llama_stack_config.api_key = "********"

src/authorization/middleware.py

@@ -4,6 +4,7 @@
 from functools import wraps, lru_cache
 from typing import Any, Callable, Tuple
 from fastapi import HTTPException, status
+from starlette.requests import Request
 
 from authorization.resolvers import (
     AccessResolver,
@@ -64,7 +65,9 @@ def get_authorization_resolvers() -> Tuple[RolesResolver, AccessResolver]:
             )
 
 
-async def _perform_authorization_check(action: Action, kwargs: dict[str, Any]) -> None:
+async def _perform_authorization_check(
+    action: Action, args: tuple[Any, ...], kwargs: dict[str, Any]
+) -> None:
     """Perform authorization check - common logic for all decorators."""
     role_resolver, access_resolver = get_authorization_resolvers()
 
@@ -93,12 +96,16 @@ async def _perform_authorization_check(action: Action, kwargs: dict[str, Any]) -
 
     authorized_actions = access_resolver.get_actions(user_roles)
 
-    try:
-        request = kwargs["request"]
-        request.state.authorized_actions = authorized_actions
-    except KeyError:
-        # This endpoint doesn't seem care about the authorized actions, so no need to set it
-        pass
+    req: Request | None = None
+    if "request" in kwargs and isinstance(kwargs["request"], Request):
+        req = kwargs["request"]
+    else:
+        for arg in args:
+            if isinstance(arg, Request):
+                req = arg
+                break
+    if req is not None:
+        req.state.authorized_actions = authorized_actions
 
 
 def authorize(action: Action) -> Callable:
@@ -107,7 +114,7 @@ def authorize(action: Action) -> Callable:
     def decorator(func: Callable) -> Callable:
         @wraps(func)
         async def wrapper(*args: Any, **kwargs: Any) -> Any:
-            await _perform_authorization_check(action, kwargs)
+            await _perform_authorization_check(action, args, kwargs)
             return await func(*args, **kwargs)
 
         return wrapper

src/models/config.py

@@ -311,6 +311,8 @@ class Action(str, Enum):
     GET_CONFIG = "get_config"
 
     INFO = "info"
+    # Allow overriding model/provider via request
+    MODEL_OVERRIDE = "model_override"
 
 
 class AccessRule(ConfigurationBase):

src/utils/endpoints.py

@@ -13,6 +13,7 @@
 from configuration import AppConfig
 from utils.suid import get_suid
 from utils.types import GraniteToolParser
+from models.config import Action
 
 
 logger = logging.getLogger("utils.endpoints")
@@ -84,6 +85,29 @@ def get_system_prompt(query_request: QueryRequest, config: AppConfig) -> str:
     return constants.DEFAULT_SYSTEM_PROMPT
 
 
+def validate_model_provider_override(
+    query_request: QueryRequest, authorized_actions: set[Action] | frozenset[Action]
+) -> None:
+    """Validate whether model/provider overrides are allowed by RBAC.
+
+    Raises HTTP 403 if the request includes model or provider and the caller
+    lacks Action.MODEL_OVERRIDE permission.
+    """
+    if (query_request.model is not None or query_request.provider is not None) and (
+        Action.MODEL_OVERRIDE not in authorized_actions
+    ):
+        raise HTTPException(
+            status_code=status.HTTP_403_FORBIDDEN,
+            detail={
+                "response": (
+                    "This instance does not permit overriding model/provider in the query request "
+                    "(missing permission: MODEL_OVERRIDE). Please remove the model and provider "
+                    "fields from your request."
+                )
+            },
+        )
+
+
 # # pylint: disable=R0913,R0917
 async def get_agent(
     client: AsyncLlamaStackClient,

tests/unit/app/endpoints/test_query.py

@@ -1507,3 +1507,60 @@ def test_evaluate_model_hints(
 
     assert provider_id == expected_provider
     assert model_id == expected_model
+
+
+@pytest.mark.asyncio
+async def test_query_endpoint_rejects_model_provider_override_without_permission(
+    mocker, dummy_request
+):
+    """Assert 403 and message when request includes model/provider without MODEL_OVERRIDE."""
+    # Patch endpoint configuration (no need to set customization)
+    cfg = AppConfig()
+    cfg.init_from_dict(
+        {
+            "name": "test",
+            "service": {
+                "host": "localhost",
+                "port": 8080,
+                "auth_enabled": False,
+                "workers": 1,
+                "color_log": True,
+                "access_log": True,
+            },
+            "llama_stack": {
+                "api_key": "test-key",
+                "url": "http://test.com:1234",
+                "use_as_library_client": False,
+            },
+            "user_data_collection": {"transcripts_enabled": False},
+            "mcp_servers": [],
+        }
+    )
+    mocker.patch("app.endpoints.query.configuration", cfg)
+
+    # Patch authorization to exclude MODEL_OVERRIDE from authorized actions
+    from authorization.resolvers import NoopRolesResolver
+
+    access_resolver = mocker.Mock()
+    access_resolver.check_access.return_value = True
+    access_resolver.get_actions.return_value = set(Action) - {Action.MODEL_OVERRIDE}
+    mocker.patch(
+        "authorization.middleware.get_authorization_resolvers",
+        return_value=(NoopRolesResolver(), access_resolver),
+    )
+
+    # Build a request that tries to override model/provider
+    query_request = QueryRequest(query="What?", model="m", provider="p")
+
+    with pytest.raises(HTTPException) as exc_info:
+        await query_endpoint_handler(
+            request=dummy_request, query_request=query_request, auth=MOCK_AUTH
+        )
+
+    expected_msg = (
+        "This instance does not permit overriding model/provider in the query request "
+        "(missing permission: MODEL_OVERRIDE). Please remove the model and provider "
+        "fields from your request."
+    )
+    assert exc_info.value.status_code == status.HTTP_403_FORBIDDEN
+    assert exc_info.value.detail["response"] == expected_msg

tests/unit/app/endpoints/test_streaming_query.py

@@ -43,7 +43,7 @@
 )
 
 from models.requests import QueryRequest, Attachment
-from models.config import ModelContextProtocolServer
+from models.config import ModelContextProtocolServer, Action
 from utils.types import ToolCallSummary, TurnSummary
 
 MOCK_AUTH = ("mock_user_id", "mock_username", "mock_token")
@@ -1515,3 +1515,63 @@ async def test_retrieve_response_no_tools_false_preserves_functionality(
         stream=True,
         toolgroups=expected_toolgroups,
     )
+
+
+@pytest.mark.asyncio
+async def test_streaming_query_endpoint_rejects_model_provider_override_without_permission(
+    mocker,
+):
+    """Assert 403 when request includes model/provider without MODEL_OVERRIDE."""
+    cfg = AppConfig()
+    cfg.init_from_dict(
+        {
+            "name": "test",
+            "service": {
+                "host": "localhost",
+                "port": 8080,
+                "auth_enabled": False,
+                "workers": 1,
+                "color_log": True,
+                "access_log": True,
+            },
+            "llama_stack": {
+                "api_key": "test-key",
+                "url": "http://test.com:1234",
+                "use_as_library_client": False,
+            },
+            "user_data_collection": {"transcripts_enabled": False},
+            "mcp_servers": [],
+        }
+    )
+    mocker.patch("app.endpoints.streaming_query.configuration", cfg)
+
+    # Patch authorization to exclude MODEL_OVERRIDE from authorized actions
+    from authorization.resolvers import NoopRolesResolver
+
+    access_resolver = mocker.Mock()
+    access_resolver.check_access.return_value = True
+    access_resolver.get_actions.return_value = set(Action) - {Action.MODEL_OVERRIDE}
+    mocker.patch(
+        "authorization.middleware.get_authorization_resolvers",
+        return_value=(NoopRolesResolver(), access_resolver),
+    )
+
+    # Build a query request that tries to override model/provider
+    query_request = QueryRequest(query="What?", model="m", provider="p")
+
+    request = Request(
+        scope={
+            "type": "http",
+        }
+    )
+
+    with pytest.raises(HTTPException) as exc_info:
+        await streaming_query_endpoint_handler(request, query_request, auth=MOCK_AUTH)
+
+    expected_msg = (
+        "This instance does not permit overriding model/provider in the query request "
+        "(missing permission: MODEL_OVERRIDE). Please remove the model and provider "
+        "fields from your request."
+    )
+    assert exc_info.value.status_code == status.HTTP_403_FORBIDDEN
+    assert exc_info.value.detail["response"] == expected_msg

tests/unit/utils/test_endpoints.py

@@ -11,6 +11,7 @@
 from models.requests import QueryRequest
 from utils import endpoints
 from utils.endpoints import get_agent
+from models.config import Action
 
 CONFIGURED_SYSTEM_PROMPT = "This is a configured system prompt"
 
@@ -591,3 +592,25 @@ async def test_get_agent_no_tools_false_preserves_parser(
         tool_parser=mock_parser,
         enable_session_persistence=True,
     )
+
+
+def test_validate_model_provider_override_allowed_with_action():
+    """Ensure no exception when caller has MODEL_OVERRIDE and request includes model/provider."""
+    query_request = QueryRequest(query="q", model="m", provider="p")
+    authorized_actions = {Action.MODEL_OVERRIDE}
+    endpoints.validate_model_provider_override(query_request, authorized_actions)
+
+
+def test_validate_model_provider_override_rejected_without_action():
+    """Ensure HTTP 403 when request includes model/provider and caller lacks permission."""
+    query_request = QueryRequest(query="q", model="m", provider="p")
+    authorized_actions: set[Action] = set()
+    with pytest.raises(HTTPException) as exc_info:
+        endpoints.validate_model_provider_override(query_request, authorized_actions)
+    assert exc_info.value.status_code == 403
+
+
+def test_validate_model_provider_override_no_override_without_action():
+    """No exception when request does not include model/provider regardless of permission."""
+    query_request = QueryRequest(query="q")
+    endpoints.validate_model_provider_override(query_request, set())