zxcvbnm987654321的专栏

收集的4种CRC校验的C程序.分为直接运算和查表法。

STC单片机IO模拟SPI协议读写W25X80.

人机交互的设计 适合每天设计 每天的日常用品 设计原则

浙江大学 计算机安全 大型作业 特此分享

Numerous Internet security incidents have shown that support from secure oper-ating systems is paramount to fighting threats posed by modern computing envi-ronments. Based on the requirements of the relevant national and international standards and criteria, in combination with our experience in the design and devel-opment of the ANSHENG v4.0 secure operating system with high security level (hereafter simply referred to as ANSHENG OS), this paper addresses the following key issues in the design of secure operating systems with high security levels: se-curity architecture, security policy models, and covert channel analysis. The design principles of security architecture and three basic security models: confidentiality, integrity, and privilege control models are discussed, respectively. Three novel se-curity models and new security architecture are proposed. The prominent features of these proposals, as well as their applications to the ANSHENG OS, are elaborated. Cover channel analysis (CCA) is a well-known hard problem in the design of secure operating systems with high security levels since to date it lacks a sound theoretical basis and systematic analysis approach. In order to resolve the fundamental difficul-ties of CCA, we have set up a sound theoretical basis for completeness of covert channel identification and have proposed a unified framework for covert channel identification and an efficient backward tracking search method. The successful ap-plication of our new proposals to the ANSHENG OS has shown that it can help ease and speedup the entire CCA process.