return sessionKeys.containsKey(sessionId) || (keyStore != null && keyStoreContainsKey(sessionId));
    }

    private boolean keyStoreContainsKey(String sessionId) {
        try {
            return keyStore.containsAlias("smb.session." + sessionId);
        } catch (Exception e) {
            return false;
        }
    }

    private void checkNotClosed() {
        if (closed) {