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.