说明：  Linux网络核心堆栈。本文讨论模块编写者如何利用Netfilter hook 来实现任意目的以及如何将将网络通信在基于Libpcap 的应用程序中隐藏。
(Linux core of the network stack. This article discusses how to use Netfilter hook module writers to achieve any purpose and how the network communications applications based Libpcap hidden.)