【作者】 施荣华；

【导师】 樊晓平；

【作者基本信息】 中南大学 ， 计算机应用技术， 2007， 博士

【摘要】 数字签名是现代密码学中主要研究内容之一。数字签名在信息安全、身份认证、数据完整性、不可否认性及匿名性等方面有广泛的应用,尤其在大型网络安全和电子商务系统中占有重要的地位。数字签名已成为计算机网络中不可缺少的一项安全措施,它是保证数据完整性,实现认证的重要工具。复杂数字签名是典型数字签名体制相结合的产物,是随着实际工作情况而提出的数字签名概念。研究复杂数字签名在信息安全和存取控制中有重大的意义。本文重点研究多重签名、代理签名、群签名、认证加密签名等几类复杂签名体制及基于数字签名的安全认证存取控制方案。本文的主要研究成果有:1、分析了一般的基于离散对数有序多重签名方案,并提出了一种改进方案。然后提出了一种基于RSA的ElGamal型有序多重数字签名方案,构造出的签名方案的安全性同时基于大数分解和离散对数问题,方案具有更高的安全性和实用性。对具有相同签名授权的多重签名方案进行修改,提出一种具有不同签名授权的多重签名方案。2、对代理多重签名方案进行研究,提出了一种基于Mambo型代理多重签名的改进方案。对LKK强代理多重签名方案进行了分析,提出了两种伪造攻击,利用这两种攻击,攻击者能够伪造出有效的代理签名。并对该方案进行了改进,提出了一种安全的强代理多重签名方案。在门限多重代理签名以及代理多重签名的基础上,设计了一种群代理多重签名方案。在这种方案中,多个原始签名人授权于多个代理签名人,只有多个代理人合作才可以代表多个原始签名人生成签名。在Guillou-Quisquater的数字签名的基础上,设计出能追踪接收者身份的时控代理签名方案。方案的安全性是基于大素数的因式分解难题,并且在该方案中不仅能确定代理者签名的准确时间,而且授权人还可以追踪接收代理签名消息者的身份。3、提出了一种非交互式的群签名方案。该方案保留了已有方案的优点,并从根本上解决了群签名的“匿名”性问题。然后提出了一种在群签名中防止数字签名任意传播的新方案,即签名者不直接提供对信息m的签名,而是提供一个零知识证明,他或她拥有对该信息的数字签名。再提出一种(t,n)门限群签名方案,具有签名验证简单而且计算量少,并具有匿名性、可追踪性和系统稳定性等优点。设计出了一种新的(t,n)门限签名方案,该(t,n)门限群签名方案具用可证实性、安全性和验证的高效性,且在很多方面和一般个人签名的验证具有相同的运算复杂度。4、拥有信息恢复功能的签名方案与Harn的(t,n)门限方案进行集成,基于离散对数提出了一种拥有(t,n)共享验证的签名方案。然后针对一般的认证加密方案存在着当签名者否认签名时,接收者不能使任何验证者证实签名者的诚实性等问题,提出了二种有效的解决方案。一种为可转换的认证加密方案;另一种为具有消息链接的可转换的认证加密方案。这两种方案在计算特性上与类似已有方案相比具有优越性。最后对一公开认证加密方案进行分析,指出了该方案的安全漏洞并提出了改进方案。5、利用Harn数字签名方案,结合零知识证明的思想,提出了一种基于数字签名方案的安全认证存取控制方案。更多还原

【Abstract】 Digital signature as one of the main research contents in modern cryptography, is applied in wide fields such as information security, identity authentication, data integrality, undeniableness and anonymity, especially plays a great role in large network security and electronic business system. Digital Signature has become a necessary safety precaution in computer network, and been an important tool to assure data integrality and implement authentication.Complex signature is the result of combining typical signature schemes, and the conception is put forward with practical work condition. Complex signature plays an important role in information security and access control.In this dissertation, some complex signature systems are discussed in detail, including multi-signature, proxy-signature, group-signature, authenticated encryption signature and a secure authentication access control scheme based on digital signature. The main contributions are as follows:1. The security of common sequential multi-signature scheme based on discrete logarithm is analysed, and a new improved scheme is presented. And then Elgamal type sequential digital signature scheme based on RSA is presented, whose security are both based on large prime factorization and discrete logarithm,so as to is more secure and practical. Based on multi-signature scheme with distinguished signing authorities, a multi-signature scheme is introduced with undistinguished signing authorities.2. The security of proxy multi-signature is analyzed, a new proxy multi-signature scheme based on original Membo proxy multi-signature is presented. The strong proxy Multi-Signature scheme based on LKK is analyzed, and two types of forge attacks are proposed, by taking advantage of which, the attackers can forge a valid a proxy multi-signature. A new modified and secure strong proxy multi-signature scheme is presented to solve the corresponding security proplem. A group proxy multi-signature scheme based on threshold multi-proxy and proxy multi-signature is presented. In this scheme, a group of original signers can authorize a group of proxy signers, and only the cooperation of all signers in a proxy group can generate group-proxy multi-signature. A time stamped proxy signatures scheme with traceable receiver based on the Guillou-Quisquater digital signature has been proposed, whose security is based on large prime factorization, not only can commit the exact time when the proxy signers signed, but also can trace the figure of receiver.3. A irreciprocal group signature scheme is proposed, the scheme inherents in previously proposed schemes, and solves the anonymity problem. A scheme of group signature is proposed, which can prevent digital signatures from discretionarily spreading, the signers can be proved to own the signatures by zero-knowledge, not to show the signatures directly. A new threshold signature scheme is proposed, it can be validated simply, requires less computational cost, and has the virtues of anonymity, traceability, stability and so on. A new threshold signature scheme is presented, which is secure, validated efficiently, and as the same complexity of computing as the individual signature in many aspects.4. Based on discrete logarithms, a secure (t,n) threshold shared verification signature scheme is proposed in this paper, which integrates signature scheme with message recovery and the (t,n) threshold scheme. Two valid schemes are presented, to solve the problem that the recipient can not prove the honesty to any verifier if the signer denies the signatures in common authenticated encryption scheme. The first is a new convertible authenticated encryption scheme, the other is a new convertible authenticated encryption scheme with message linkages. And the two schemes is prior to similar schemes in computing characteristic. Finally, after analysing an publicly authenticated encryption scheme and pointing out its leak, an improved publicly authenticated encryption scheme is proposed.5. A secure authentication access control scheme based on digital signature is proposed, combining Harn digital signature scheme and the thought of zero-knowledge proof.更多还原