Endpoints: Add key permission checker

This is a definite way to check if an authorized key is API or admin.
The endpoint only runs if the key is valid in the first place to keep
inline with the API's security model.

Signed-off-by: kingbri <bdashore3@proton.me>

common/auth.py

@@ -10,6 +10,8 @@ from pydantic import BaseModel
 from loguru import logger
 from typing import Optional
 
+from endpoints.OAI.types.auth import AuthPermissionResponse
+
 
 class AuthKeys(BaseModel):
     """
@@ -75,6 +77,18 @@ def load_auth_keys(disable_from_config: bool):
     )
 
 
+async def validate_key_permission(test_key: str):
+    if test_key.lower().startswith("bearer"):
+        test_key = test_key.split(" ")[1]
+
+    if AUTH_KEYS.verify_key(test_key, "admin_key"):
+        return AuthPermissionResponse(permission="admin")
+    elif AUTH_KEYS.verify_key(test_key, "api_key"):
+        return AuthPermissionResponse(permission="api")
+    else:
+        raise ValueError("The provided authentication key is invalid.")
+
+
 async def check_api_key(
     x_api_key: str = Header(None), authorization: str = Header(None)
 ):

endpoints/OAI/app.py

@@ -2,15 +2,16 @@ import pathlib
 import signal
 import uvicorn
 from contextlib import asynccontextmanager
-from fastapi import FastAPI, Depends, HTTPException, Request
+from fastapi import FastAPI, Depends, HTTPException, Header, Request
 from fastapi.middleware.cors import CORSMiddleware
 from functools import partial
 from loguru import logger
 from sse_starlette import EventSourceResponse
 from sys import maxsize
+from typing import Optional
 
 from common import config, model, gen_logging, sampling
-from common.auth import check_admin_key, check_api_key
+from common.auth import check_admin_key, check_api_key, validate_key_permission
 from common.concurrency import (
     call_with_semaphore,
     generate_with_semaphore,
@@ -22,6 +23,7 @@ from common.templating import (
     get_template_from_file,
 )
 from common.utils import (
+    coalesce,
     handle_request_error,
     unwrap,
 )
@@ -399,6 +401,32 @@ async def decode_tokens(data: TokenDecodeRequest):
     return response
 
 
+@app.get("/v1/auth/permission", dependencies=[Depends(check_api_key)])
+async def get_key_permission(
+    x_admin_key: Optional[str] = Header(None),
+    x_api_key: Optional[str] = Header(None),
+    authorization: Optional[str] = Header(None),
+):
+    """
+    Gets the access level/permission of a provided key in headers.
+
+    Priority:
+    - X-api-key
+    - X-admin-key
+    - Authorization
+    """
+
+    test_key = coalesce(x_admin_key, x_api_key, authorization)
+
+    try:
+        response = await validate_key_permission(test_key)
+        return response
+    except ValueError as exc:
+        error_message = handle_request_error(str(exc)).error.message
+
+        raise HTTPException(400, error_message) from exc
+
+
 # Completions endpoint
 @app.post(
     "/v1/completions",

endpoints/OAI/types/auth.py

@@ -0,0 +1,7 @@
+"""Types for auth requests."""
+
+from pydantic import BaseModel
+
+
+class AuthPermissionResponse(BaseModel):
+    permission: str