case ErrServerNotInitialized:
		return ErrSTSNotInitialized
	case ErrInternalError:
		return ErrSTSInternalError
	default:
		return ErrSTSAccessDenied
	}
}

func checkAssumeRoleAuth(ctx context.Context, r *http.Request) (auth.Credentials, APIErrorCode) {
	if !isRequestSignatureV4(r) {
		return auth.Credentials{}, ErrAccessDenied
	}