Files
monlet/server/monlet_server/middleware/auth.py
2026-05-28 14:19:27 +04:00

43 lines
1.5 KiB
Python

import hmac
from starlette.middleware.base import BaseHTTPMiddleware
from starlette.requests import Request
from ..agent_auth import credential_from_token
from ..errors import error_response
from ..settings import get_settings
NO_AUTH_PATHS = {"/api/v1/health", "/api/v1/ready", "/metrics"}
AGENT_PATHS = {"/api/v1/heartbeat", "/api/v1/events"}
def _match_token(presented: str, accepted: list[str]) -> bool:
matched = False
# Constant-time across all accepted tokens to avoid timing oracle.
for t in accepted:
if hmac.compare_digest(presented, t):
matched = True
return matched
class BearerAuthMiddleware(BaseHTTPMiddleware):
async def dispatch(self, request: Request, call_next):
path = request.url.path
if path in NO_AUTH_PATHS:
return await call_next(request)
header = request.headers.get("authorization")
if not header or not header.lower().startswith("bearer "):
return error_response(request, 401, "unauthorized", "authentication required")
token = header.split(" ", 1)[1].strip()
if path in AGENT_PATHS:
if len(token) < 32 or len(token) > 512:
return error_response(request, 401, "unauthorized", "authentication required")
request.state.agent_credential = credential_from_token(token)
else:
if not _match_token(token, get_settings().auth_tokens):
return error_response(request, 401, "unauthorized", "authentication required")
return await call_next(request)