VxD技术分析与开发

利用虚拟设备驱动程序VxD对硬件设备进行虚拟化,通过VxD实施对硬件设备的管理与控制.VxD本质上是被用来管理系统资源(硬件或者软件)、运行于系统核心级Ring0的可执行二进制代码,通过设备驱动程序,多个线程可以同时使用这些资源,从而实现多进程并行运行.VxD通常包括5个段,其核心段是保护模式代码段VxD＿CODE,其中包含了虚拟设备的设备控制例程,回调函数,服务例程和API函数.开发VxD的工具软件很多,具有代表性的主要是DDK、WinDriver和VToolsD.在深入分析Windows9x的VxD技术的实现机制与原理的基础之上,讨论了基于VToolsD的虚拟设备驱动程序VxD开发方法,并给出了一个编程实例.参6.

Analysis and development of virtual device driver (VxD)

Operating system virtualize the hardware device with virtual device driver program (VxD), and manager and control the hardware by VxD. In fact, VxD is an executable binary code running in Ring0 of operating system. VxD is used to manager system resources including hardware and software. Using VxD, many threads may use the same hardware or software during the same time. Thus, many program may run parallel. VxD includes usually five segments. The main segment of a VxD is protected mode code segment (Vxd_CODE). The VxD_CODE segment includes the example programs for device control, the functions for callback, the service programs and the API functions. There are many tool software to develop VxD program. The main tools are DDK, WinDriver and VtoolsD. In this paper, it analyzes the principle and realization of the VxD technology under Windows9x. It discusses the develop method of VxD based VToolsD, and provides a sample to develop VxD.6refs.