【作者】 杨峰；

【导师】 易小琳；

【作者基本信息】 北京工业大学 ， 计算机科学与技术， 2010， 硕士

【摘要】 互联网技术的蓬勃发展使得信息安全领域面临重大的挑战。个人信息泄漏,恶意木马篡改,密钥的丢失等成为严重的网络安全隐患。人们在探索研究一种更为可靠的安全机制的道路上付出了巨大的艰辛。传统的数据加密,信息认证,数字签名等安全机制越来越不能胜任当前复杂多变的网络环境。本课题所研究的内容基于一种先进的信息安全解决方案,即采用嵌入式设备对信息进行加密解密处理,同时负责密钥的管理;采用目前公认的安全性最高的椭圆曲线密码体制(Elliptic Curve Cryptography, ECC)加密算法对数据进行保密处理。这样的系统可以最大限度地将数据的加密、解密过程与PC相隔离,同时保护了密钥,防止恶意木马的攻击和信息的泄漏,也杜绝了数据信息在传输过程中被攻击者截获并破解的可能。但是这样的系统会存在着两个不可回避的问题,一是ECC算法复杂度过高,性能不佳,尤其很难与低端的嵌入式设备相兼容;二是由于嵌入式系统自身的可靠性缺陷所带来的数据传输以及数据存储过程中的容错问题。本论文主要围绕着嵌入式加密系统中存在的这两个关键问题开展研究和讨论。本文首先分析了ECC算法的瓶颈,找到影响ECC算法性能的关键因素,并结合本嵌入式系统所使用的ECC算法提出了从大数模幂和大数模乘两级改善整体算法性能的方案。这个算法改进方案属于ECC算法素域运算层的改进方案,经过测试,算法性能改进明显。接下来本文讨论了嵌入式系统在数据传输以及数据存储过程中的容错问题,具体结合本课题所研究的系统,分析了系统容错的需求。同时提出了一种基于本原BCH码的Nand Flash的容错方案,并提出了BCH容错系统的软件实现方法,通过演示程序给出了系统的测试结果。嵌入式系统ECC算法性能改进方案以及系统容错方案的提出对于应用于低端嵌入式设备中的ECC算法的性能改进以及一些资源稀缺、可靠性一般的相关嵌入式加密系统、嵌入式Nand Flash存储设备的开发具有实际意义。更多还原

【Abstract】 The rapid development of internet technology has made information security is facing major challenges. Personal information leakage, malicious Trojan tampering and loss of secret key have become serious security risk of networks. People pay a great hardship to research a more reliable security mechanism. Traditional data encryption, message authentication, digital signature and other security mechanisms become increasingly incapable about current complex network environment.The study content of my subject is based on an advanced information security solution. That is using embedded device for encryption and decryption of information processing, also responsible for secret key management, using the currently accepted the highest safety Elliptic Curve Cryptography ECC encryption algorithm on data confidential. Such a system can maximize to isolate the process of encryption and decryption to PC,while protect the secret key and prevent the malicious Trojan horse attack and information leakage, but also put an end to the possibility of the data could be intercepted and deciphered by the attacker during transmission.However there are two unavoidable problems in this system. One is the high complexity and poor performance existing in ECC algorithm, so as to it is not compatible with low-end embedded device and the other is the need of fault-tolerant for embedded system in the data transmission process and data store process since the reliability of the embedded system itself. So this paper gives discussion and analysis around the two issues.Firstly this paper analyzes the bottleneck that impact ECC algorithm performance, and provides a new method, that modify the module exponentiation sub-algorithm and module multiplication sub-algorithm to speed up whole algorithm computation according the real ECC algorithm used in this system. This algorithm improvement program belongs to prime field operation level of ECC algorithm, and the obvious improvement was shown by test results.Secondly this paper discusses fault-tolerant technology in the process of data transmission and data store, and combined with the system studied in this issue, analysis fault-tolerance requirement of this embedded system. At the same time, this paper proposes Primitive BCH Code based fault-tolerant program, proposes the specific method of how to program to realize the system and gives a demo procedure. ECC algorithm performance improvement program of embedded system and system fault-tolerant program are meaningful to the improvement of ECC algorithm that is used in embedded device and the development of embedded encryption system and embedded Nand Flash storage device with scarce resources and low reliability.更多还原