基于自动机理论的同时签名算法研究与实现

【作者】 周睿；

【导师】 叶有培；

【作者基本信息】 南京理工大学 ， 计算机应用技术， 2008， 硕士

【摘要】 电子商务是基于Internet的双方或多方之间进行的有形商品或者无形服务的交换,公平交换协议在电子商务中有着广泛的应用。同时签名是一种能够用来解决数字签名公平交换问题的签名方案,由Chen等人在2004年最早提出,其基本思想是签名双方在没有可信第三方TTP(Trusted Third Party)的帮助下进行交互,公平地完成对各自消息的签名和交换。有限自动机公钥密码体制(FAPKC)是由我国学者陶仁骥和陈世华自主提出的,基于有限自动机可逆性理论的一种公钥密码体制,这是国际上第一个时序型公钥密码体制,由于只涉及到逻辑运算,与其他主流的公钥密码体制相比,该体制具有实现简单,运算速度较快的优势。本文的工作主要有以下几点:一、全面总结了近年来同时签名的发展和研究情况,介绍了同时签名方案、完美同时签名方案、多方同时签名方案,并对这些方案的安全性进行了分析。二、提出了基于有限自动机理论的完美同时签名方案(FAPCS),定义了该方案的算法和协议,引入了完美模糊性和完美公平性的概念,并由此定义了完美同时签名方案的安全性模型,最后给出了FAPCS方案的安全性证明。三、用C++语言实现了FAPCS方案,定义了基本数据类型,定义并实现了核心算法对应的API,并给出了一个Demo程序,演示了同时签名协议的执行流程及API的调用顺序。本文最后讨论了目前尚未解决的问题,展望了同时签名方案未来的发展方向以及进一步的工作。更多还原

【Abstract】 Electronic Commerce is the Internet-Based exchange of tangible merchandize or intangible service between two or more parties, the fair exchange protocol have been widely used in electronic commerce. Concurrent signature is designed to resolve the fair exchange problem of digital signature, which was proposed by Chen et al. in 2004.Two Chinese cryptographers Tao Renji and Chen Shihua introduced the Finite Automata Public Key Cryptosystem (FAPKC), which is based on the invertibility theory of finite utoma. It is the first time-sequence public key cryptosystem. Compared with other popular public key systems, FAPKC is easy to be implemented and is more efficient because it only uses logical operations.This paper chiefly refers to the following works:1. Summarizes the research on Concurrent Signature in recent years. Introduces Concurrent Signature Scheme, Perfect Concurrent Signature Scheme, Multi-Party Concurrent Signature Scheme, and analyzes the security of these schemes.2. Proposes a concrete Perfect Concurrent Signature scheme based on FAPKC. Defines the security model and introduces the notion of Perfect Ambiguity and Perfect Fairness. Proves that FAPCS scheme satisfies the security model.3. Implements the FAPCS scheme using C++ language. Defines the basic data structure, the core algorithms, gives out a concrete demo to illustrate the FAPCS protocol and the calling sequence of the core algorithms.At last, some open questions and future work are discussed.更多还原