KFUR:一个新型内核扩展安全模型

保障内核扩展的安全性对操作系统具有重要意义.当前存在大量针对内核函数使用规则的攻击,内核扩展中也存在大量违反内核函数使用规则的错误,因此针对内核函数使用规则的安全性检测十分必要.虽然存在多种提高内核扩展安全性的方法,但很少有方法对内核函数的使用规则进行安全性检测.文中设计了KFUR( Kernel Function Usage Rule)内核扩展安全模型系统,用于在运行时检测内核扩展调用内核函数是否遵守内核函数使用规则.如果内核扩展调用内核函数满足模型安全运行条件,则允许对该内核函数进行调用,否则将错误报告给操作系统内核并终止该内核扩展的运行.文中所述研究在Iinux操作系统上对KFUR安全模型系统进行实现,并将其运用于e1000网卡驱动、SATA硬盘驱动和HDA声卡驱动内核扩展.安全性评测表明安全模型系统能够对内核函数使用规则进行安全性检测,性能评测表明安全模型系统带来的开销很小.     

电子文档安全管理技术研究与实现

设计并实现了一个具有文件安全保护能力的终端文档安全保护系统。在技术上主要采用内核与应用层相结合的方法来实现文档透明加、解密。在内核层实现功能上的控制,而在应用层实现相应的权限控制和策略制定。在操作系统内核对访问电子文档的进程进行审核与控制,利用文件系统过滤驱动技术过滤掉非法进程对文档的读取。对于拥有访问权限和安装该系统的客户端用户,才可以正常读取加密的电子文档,排除了电子文档泄密的可能,实现了对电子文档的安全管理。     

基于文件系统过滤驱动的加密系统设计与实现

针对传统应用层加密系统每次使用都需要输入口令,使用复杂且安全性不高,而设备驱动层加密系统紧耦合于操作系统及其组件,实现繁杂等问题,在Windows NT内核框架下利用文件系统过滤驱动实现数据加解密的安全保护系统。结果证明可以对存取中的数据进行动态透明的加解密,使用方便安全,支持多种文件系统。从安全性和性能上对比了该加密系统与Windows EFS加密文件系统。     

基于虚拟设备的访问控制模型

访问控制系统需具备便携性、易用性。基于此,提出一种Windows操作系统I/O模型下的访问控制模型。该模型基于以加密文件为容器的虚拟设备,在用户态和内核态进行授权判定、透明加解密、访问重定向,可扩展为各种定制访问控制系统。根据需求进行模块设计,使用API钩子、虚拟设备驱动和过滤驱动等技术开发,测试包括性能的模型特点,并给出2种应用扩展。     

面向高可用计算机的驱动隔离系统设计与实现

为了减少驱动程序中存在的缺陷对系统运行造成的严重影响,研究并实现了一种在操作系统内核的基本部分与设备驱动程序之间增加“驱动隔离层”的内核驱动隔离机制,同时提供驱动程序发生故障后的检测及恢复机制.这种将驱动程序隔离运行的机制明显区别于传统的操作系统,能够对系统内核区域进行严格的访问控制保护,避免了由于驱动程序存在缺陷所导致的系统失效.实验结果表明,该内核驱动隔离系统有效地提高了系统的可用性,同时对用户和应用程序透明,具有良好的兼容性.     

面向内部网络的电子文档保护系统

本文针对内部网络中信息泄密问题,设计并实现了一种电子文档保护系统,该系统基于Windows NT内核操作系统驱动框架,采用文件系统过滤驱动技术对内部网络数据进行实时透明加密和解密,为内部网络的数据安全提供了有效的主动安全防护。     

一种新型的基于构件和微内核的设备驱动模型

论文首先从内核性能和安全性的角度分析驱动程序对微内核与单体内核的影响;然后讨论硬件抽象层对驱动抽象能力的影响以及与移植性及内核大小的关系;分析传统UNIX系列与Windows NT操作系统内核结构以及驱动模型优缺点;最后介绍一个构件化驱动模型的特点。该模型基于构件装配运行平台技术,运行在和欣2.0操作系统平台上。驱动模型底层是一个合适的硬件抽象层,方便移植,用户态程序可以灵活地调用驱动程序。     

基于文件系统过滤驱动的安全增强型加密系统技术研究

应用层加密系统在实际的应用中一般要求用户在访问文件前手动进行加解密操作,有些系统中文件正常使用时必须以明文形式存储在磁盘上.基于文件系统驱动的加密文件系统减少了用户的参与操作,同时保证了磁盘上文件处于加密状态,但是其在设计与实现上较为复杂.针对上述方法存在的问题,本文采用Windows NT内核操作系统的驱动框架,基于文件系统过滤驱动技术实现对数据进行透明加解密.通过这种方法不仅解决了应用层加密系统存在的不足,与加密文件系统相比开发实现较简单灵活.另外使用智能卡作为加解密密钥的存储容器,进一步增强整个系统的安全性.     

基于数据特征的内核恶意软件检测

内核恶意软件对操作系统的安全造成了严重威胁.现有的内核恶意软件检测方法主要从代码角度出发,无法检测代码复用、代码混淆攻击,且少量检测数据篡改攻击的方法因不变量特征有限导致检测能力受限.针对这些问题,提出了一种基于数据特征的内核恶意软件检测方法,通过分析内核运行过程中内核数据对象的访问过程,构建了内核数据对象访问模型;然后,基于该模型讨论了构建数据特征的过程,采用动态监控和静态分析相结合的方法识别内核数据对象,利用EPT监控内存访问操作构建数据特征;最后讨论了基于数据特征的内核恶意软件检测算法.在此基础上,实现了内核恶意软件检测原型系统MDS-DCB,并通过实验评测MDS-DCB的有效性和性能.实验结果表明：MDS-DCB能够有效检测内核恶意软件,且性能开销在可接受的范围内.     

基于过滤驱动的文件保护系统

数据的安全保护是当前网络安全领域研究的热点,本文提出了一种基于文件系统过滤驱动的文件保护系统。该文件保护系统在操作系统内核状态下实现了对文件的透明加/解密,并提供了访问控制、密钥管理等功能。加/解密算法可以灵活采用并且不公开,提高了加密的有效性。文件以密文的形式保存,且只能被合法用户以非常安全的方式访问。用户使用起来非常方便,只需提供自己的私钥即可。     

Windows CE.net设备驱动程序开发研究

介绍了Windows CE．net的平台结构，阐述了Windows CE驱动的系统结构，对驱动中断处理过程进行了详细分析。并以LCD驱动为例，简介了嵌入式Windows CE驱动程序的开发讨程.     

CITECT驱动程序开发方法及其通用性研究

通过对CITECT驱动程序工作方式的分析,讨论了CITECT驱动程序的开发过程和方法,给出一种基于CITDDK工具包开发CITECT工控组态软件与非标准化硬件设备通讯驱动程序的实现方法,并就实现过程中驱动程序的通用性进行详细的探讨。     

Speech Recognition and In-Vehicle Telematics Devices: Potential Reductions in Driver Distraction

Speech Recognition is frequently cited as a potential remedy to distraction resulting from drivers' operation of in-vehicle devices. This position typically assumes that the introduction of speech recognition will result in reduced cognitive workload and improved driving performance. Past research neither fully supports nor fully discounts this assumption. However, it is difficult to compare many of these studies, due to differences in device operation tasks, the pacing of those tasks, speech recognition system performance, and system interface designs. In an effort to directly address the effect of voice recognition on driver distraction, the present authors developed a capability to manipulate the performance characteristics of a speech recognition system through a Wizard of Oz speech recognition system and installed this system in a simulated driving environment. The sensitivity of the simulated driving environment and speech recognition accuracy manipulation were evaluated in an initial study comparing driver cognitive workload and driving performance during self-paced simulated operation of a personal digital assistant (PDA) during no PDA use, manual control of the PDA, and speech control of the PDA. In the Speech PDA condition, speech recognition accuracy was varied between drivers. Analysis of drivers' emergency braking response times and rated cognitive workload revealed significantly lower cognitive demand and better performance in the No PDA condition when compared to the Manual PDA condition. The Speech PDA condition resulted in response times and rated cognitive workload levels that were between the No PDA and Manual PDA conditions, but not significantly different from either of these conditions. Further analysis of emergency braking performance revealed a non-significant trend towards better performance in conjunction with higher speech recognition accuracy levels. The potential for reducing driver distraction through the careful development and evaluation of speech recognition systems is discussed.     

Voltage driven hard disk drive with voice coil model-based control

In this paper, we describe a new solution for driving the voice coil motor (VCM) in hard disk drives (HDDs), in which the usual current driver for the voice coil motor has been replaced by a voltage driver. When used in conjunction with PWM power stages, this solution becomes fully digital and has proven advantages in terms of cost, power dissipation and silicon area. To achieve the same performance of the current driver, the voltage driver requires a pre-filter placed at its input, to cancel out the electrical pole of the VCM. In the paper, we describe the voice coil model-based control (VCMC), a solution for implementing the pre-filter, which replicates the behavior of a current loop by using a model of the voice coil motor and its driver, including the saturation of the power stage. It is worth noticing that VCM resistance may change by 30% during HDD operations, increasing when the disk is performing repetitive seeks or decreasing when the disk cools down during track following. Such variation may lead to an unsatisfactory performance of the VCMC, so an adaptation mechanism, capable of tracking variations of VCM coil resistance, must be set up. This paper presents a pair of on-line estimation procedure, used to get the value of the VCM coil resistance during seek and track following, respectively. The first one is based on a standard LMS approach, aimed at identifying a simplified model of the plant with the least computational effort. The second exploits the presence of repetitive disturbances (RROs) to detect variations of plant gain and, in turn, of VCM resistance. It will be shown that both procedures are quite accurate in estimating variations of VCM resistance and their output can be used to perform on-line tuning of the VCMC. Experimental results show that the servo performance with the adaptive VCMC is not affected by resistance variation and equivalent to that of the standard current driver.     

基于WDM的交流伺服电机运动控制器

讨论ISA伺服控制卡在Win2000环境下的工作过程以及WDM设备驱动程序的原理、结构和运行过程,以ISA总线为例研究WDM设备驱动程序的设计与开发。编写伺服控制程序并设计PID控制器,在线调整控制参数。交流伺服电机实验结果表明,通过编写设备驱动程序可以实现高精度定时,满足较高精度的伺服电机位置控制要求。     

RTX下的驱动及Simulink模块封装技术

研究基于RTX和Matlab实时仿真技术对帧时间要求苛刻的实时仿真应用具有重要的意义.但如果进行半实物仿真,就需要解决制作可以在RTX下运行的PCI板卡驱动的关键问题.VC6.0下编写了硬件驱动库函数RTDLL文件.同时将在Matlab下编写S函数调用库函数完成Simulink模块的封装,最后通过配置RTW工具箱生成RTX下可执行的程序RTSS.     

一种跨平台实时控制系统设备驱动的设计与实现

针对实时控制系统接入各种现场设备并与之通讯的问题,提出并设计了一种跨平台实时控制系统的现场设备驱动。首先概述了设计的基本原理,然后详细阐述了驱动函数,驱动模块,驱动引擎等各模块的设计及在多操作系统平台的实现。最后以实际的使用示例说明设备驱动的使用方法。     

Development and validation of a self-report measure of bus driver behaviour

There are likely to be individual differences in bus driver behaviour when adhering to strict schedules under time pressure. A reliable and valid assessment of these individual differences would be useful for bus companies keen to mitigate risk of crash involvement. This paper reports on three studies to develop and validate a self-report measure of bus driver behaviour. For study 1, two principal components analyses of a pilot questionnaire revealed six components describing bus driver behaviour and four bus driver coping components. In study 2, test–retest reliability of the components were tested in a sub-sample and found to be adequate. Further, the 10 components were used to predict bus crash involvement at three levels of culpability with consistently significant associations found for two components. For study 3, avoidance coping was consistently associated with celeration variables in a bus simulator, especially for a time-pressured drive.

Statement of Relevance:The instrument can be used by bus companies for driver stress and fatigue management training to identify at-risk bus driver behaviour. Training to reduce the tendency to engage in avoidance coping strategies, improve evaluative coping strategies and hazard monitoring when under stress may improve bus driver safety.     

The use of modula

Three sample programs are developed and explained with the purpose of demonstrating the use of the programming language Modula. The examples concentrate on the uses of modules, concurrent processes and synchronizing signals. In particular, they all focus on the problems of operating peripheral devices. The concurrency of their driver processes has to occur in real time. The devices include a typewriter, a card reader, a line printer, a disk, a terminal with tape cassettes and a graphical display unit. The three programs are listed in full.     

基于Windows CE.Net的AD驱动程序设计与实现

在嵌入式系统的开发中,驱动程序的开发是非常重要的。本文主要讨论在Windows CE.Net操作系统下,如何设计实现S3C2410芯片具有AD接口的驱动程序;详细介绍Windows CE.Net下,流接口驱动程序的编写方法,同时将驱动通过Platform Builder编译进操作系统,最后用动态链接库的方式提供给应用软件开发者。