【作者】 杨晨；

【导师】 王新梅；

【作者基本信息】 西安电子科技大学 ， 通信与信息系统， 2007， 博士

【摘要】 密码协议是网络环境中提供身份认证性、数据完整性和不可否认性的关键技术,是构建安全网络环境的基石,在付费电视、在线数据库等多媒体业务所基于的安全网络系统中起着重要作用。双线性对是近几年发展起来的用来构造密码协议的一个重要工具。利用双线性对构造的密码协议不仅具有高安全性、短密钥和快速实现等优点,还具有更多的用其它方法难以实现的功能。本文从多媒体信息安全保护中的叛逆者追踪、数字签名、身份认证以及群密钥分发等方面对基于双线性对的密码协议进行了深入的研究,主要研究成果有:1.提出了一个基于双线性对的能够有效对抗单用户匿名盗版攻击的叛逆者追踪方案,并且构造了一个具有限制盗版能力的黑盒追踪算法。该方案具有以下优点(1)需要的数据传输带宽独立于系统用户的数量:(2)可以检测出所有参与盗版解码器构造的系统授权用户;(3)也可以用来构造公钥叛逆者追踪方案。2.研究了具有安全中介结构的无证书公钥密码体制,给出了基于安全中介的无证书公钥加密方案和数字签名方案的形式化定义。利用双线性对构造了一个有效的基于安全中介的无证书公钥加密方案,消除了传统的基于身份的密钥体制中存在的密钥托管问题,并实现了用户密钥的快速撤销。3.通过引入在线的SEM机制,提出了一个具有安全中介结构的基于身份的数字签名方案。该方案实现了用户密钥的快速撤销,在计算Diffie-Hellman问题困难性假设下能安全抵御存在性签名伪造攻击。4.分析了Ju等提出的可即时撤销的数字签名方案的安全性,指出当签名用户在安全中介协助下成功完成一次消息签名后,该方案则不再满足即时撤销的特性。提出了针对Ju方案的改进方案。5.利用超椭圆曲线上的双线性对,采用将用户选取的初始口令与其身份信息绑定的策略设计了一个基于智能卡的远程用户口令认证方案。该方案允许用户自由选取和更换自己的登陆口令,并且不需要认证服务器存储口令验证列表,从而减少了认证服务器的存储负担。6.引入密钥代理量概念构造了一个基于智能卡的远程用户认证方案。在计算用户的密钥时,同时计算该密钥对应的密钥代理量并存储于用户持有的智能卡中来计算用户的登录请求信息,增强了系统抗合谋攻击的安全性。7.基于双线性对构造了一个基于身份的群密钥分发方案。该方案所需广播传输的控制报头信息量独立于系统用户数,因此特别适用于大用户集的情况,并且实现了用户的动态加入。更多还原

【Abstract】 Cryptographic protocol is one of the key techniques to provide identity authentication, dada integration and non-repudiation in the network environment. It plays an important role in the secure networks systems on which the multimedia services (e.g. Pay-TV, Online Database) are based, and it is the foundation for establishing the secure network environment.Bilinear pairings is a crucial tool for constructing the cryptographic protocols in recent years. The bilinear pairing-based cryptographic protocols not only have the advantages of higher security, shorter key size and faster implementation, but also possess many benefits that cannot be easily achieved by using other techniques. This dissertation focuses on the design and analysis of the pairing-based cryptographic protocols in following aspects: traitor tracing, digital signature, identity authentication and group key distribution of the multimedia information protection. The main contributions of this dissertation are as follows:1. A new pairing-based traitor tracing scheme that can efficiently resist single-user anonymous pirate attack is proposed, and the corresponding black-box tracing algorithm with limited pirate capability is also constructed. The proposed scheme has the following advantages: (1) The data transmission bandwidth needed is independent of the number of the users in the system; (2) All the authorized users contributing to the construction of the pirate decoder can be detected; (3) The scheme can be used to construct public key traitor tracing schemes.2. We study the certificateless public-key cryptosystem using SEM (SEcurity Mediator) mechanism, and present the formal models of the SEM-based certificateless public-key encryption scheme and certificateless signature scheme respectively. An efficient SEM-based certificateless public-key encryption scheme using bilinear pairing is proposed. The proposed scheme can eliminate the key escrow problem in traditional identity-based public-key cryptosystem, and also realize the immediate revocation of user keys.3. A mediated identity-based signature scheme is presented by introducing the online SEM mechanism. The scheme can provide fast user-key revocation and securely withstand existential forgery attack under the difficulty of computational Diffie-Hellman assumption.4. Security analysis is conducted for Ju et al’s signature scheme with immediate revocation. As pointed out, the immediate revocation property will be damaged once the system user has successfully completed one message signature with the help of the SEM. We propose an improved scheme that does not have the above weakness.5. By binding the initial password selected by one user with his identity information, we present a smartcard-based remote user password authentication scheme using bilinear pairings derived from hyperelliptic curves. The proposed scheme enables each user to choose and change his login password freely to achieve the aim of the user-friendly. Additionally, there is no need to use any verifier table to verify each user’s login request, and thus the authentication server’s storage burden is greatly reduced.6. The notion of key proxy quantity is introduced to construct remote user authentication scheme using smart card. The authentication server generates for each user a key along with the corresponding proxy quantity stored in the smartcard which is given to the user to compute the login request, which enhances the system security against collusion attack.7. An identity-based group key distribution scheme using bilinear pairings is constructed. The broadcasting controlling information in the scheme is independent of the number of the users in the system. Therefore, the proposed scheme is suitable for the situation with large set of system members. The proposed scheme can also provide dynamic user joining.更多还原