一种高效的广义指定验证者签名证明

Joonsang Baek等人提出了一种新型的广义指定验证者签名（UDVS）称为广义指定验证者签名证明（UDVSP）．本文提出一个高效的基于Zhang-Safavi—Susilo（ZSS）签名方案的广义指定验证者签名证明．利用双线性对的性质和预计算，所提方案中仅仅需要2个对运算，同时只使用通常密码学上的hash函数，而不需要特殊的hash函数（映射到点）．在随机预言机模型中，证明该方案是安全的．     

一种基于证书的带消息恢复的代理签名方案

针对基于身份公钥密码体制中固有的密钥托管和传统公钥密码系统中证书管理问题,结合基于证书公钥密码系统的优点和消息恢复签名的特点,设计了一种基于证书的带消息恢复的代理签名方案,该方案基于离散对数问题和计算Deffie-Hellman问题假设,可限制代理人滥用代理权力,具有正确性、不可伪造性和不可否认性,最后给出了证明。     

带消息恢复的可证明安全自证书签名方案

To solve the key escrow problem of the identity-based cryptosystem, Girault introduced the notion of a self-certified public key, which not only eliminates the need to authenticate a public key but also solves the key escrow problem. This paper proposes a Self-Certified Signature (SCS) scheme with message recovery and two variants without using bilinear pairings: one is the authenticated encryption scheme in which only the designated receiver can verify the signature, and the other is the authenticated encryption scheme with message linkage that deals with large messages. These three SCS schemes are provably secure in the random oracle model and are more efficient than previous schemes.     

Constructing Strong Identity‐Based Designated Verifier Signatures with Self‐Unverifiability

An identity‐based strong designated verifier signature scheme provides restricted verifiability only for a verifier designated by a signer and proper privacy for the signer. In this paper, we show that strong designated verifier signature schemes do not satisfy the self‐unverifiability requirement in the sense that not only exposure of the verifier's secret key but also of the signer's secret key enables an attacker to verify signatures, which should have been the exclusive right of the verifier. We also present a generic method to construct a strong identity‐based designated verifier signature scheme with self‐unverifiability from identity‐based key encapsulation and identity‐based key sharing schemes. We prove that a scheme constructed from our method achieves unforgeability, non‐transferability, and self‐unverifiability if the two underlying components are secure. To show the advantage of our method, we present an example that outputs short signatures and we analyze its performance.     

可证明安全的智能移动终端私钥保护方案

提出一种可证明安全的智能移动终端私钥保护方案。充分利用口令保护、密钥分割与服务器动态交互获取部分私钥等技术保证用户私钥安全。与其他方案相比,该方案的优势在于：减少了智能移动终端的计算量和存储量,简化了交互过程参数的设置;将时间同步贯穿整个方案的设计过程,防止重放攻击的同时,更提供了便捷高效的用户私钥失效方案。方案达到了安全私钥获取和高效私钥失效的效果,符合智能移动终端的安全应用需求,在随机预言机模型下是可证明安全的。     

密码学中的随机预言模型与标准模型

随机预言模型与标准模型是密码学可证明安全理论中非常重要的两类模型。在此对这两种模型进行了描述,并研究了运用它们证明密码方案或协议安全性时所采取的不同技术,包括随机预言模型在加密和数字签名方案中的应用研究,以及标准模型下可证明安全性理论在加密方案中的应用研究。此外对进一步研究方向进行了展望。     

对一个基于身份签密方案的分析与改

基于身份的签密方案计算开销小,密钥管理简单,适用于保证信息的保密性和认证性。Zhang等提出了一个高效的基于身份签密方案,并在随机预言模型下证明了该方案的安全性。通过分析发现Zhang等的签密方案存在缺陷,针对缺陷提出了相应的改进方案,并且基于随机预言模型证明了新方案的安全性。理论分析和实验仿真证明,所提方案计算复杂度低,适合于实际应用。     

可证明安全的RFID通信安全协议

通过对RFID系统特殊安全问题的系统研究,从可证明安全论证的角度出发,本文提出了一种可证明安全的RFID通信安全协议——rPAP。在随机预言模型下,使用形式化描述方式,系统地建立了RFID通信安全模型,并在该模型下,形式化地论证了rPAP协议的安全性。该协议适用于一般的RFID系统。     

Provable data possession scheme with authentication

To satisfy the requirements of identity authentication and data possession proven in the cloud application scenarios,a provable data possession scheme with authentication was proposed.Based on data tag signature and randomness reusing,the proposed scheme could accomplish several issues with three interactions,including the possession proof of cloud data,the mutual authentication between user and cloud computing server,the session key agreement and confirmation.Compared to the simple combination of authentication key agreement and provable data possession schemes,the proposed scheme has less computation and interactions,and better provable securities.In the random oracle model,the security proof of the proposed scheme is given under the computational Diffie-Hellman assumption.     

一种可证安全的紧致无证书聚合签名方案

聚合签名能够实现批验证,特别适用于资源受限的无线网络中批量身份认证.无证书密码体制能够解决聚合签名的证书管理或私钥托管问题.本文首先对一个无证书聚合签名方案进行分析,随后提出更加安全高效的无证书聚合签名方案,方案验证时需要更少的双线性对操作.最后在随机预言模型下证明方案具有不可伪造性,其安全性等价于求解CDH（Computation Diffie-Hellman）困难问题.     

适合无线传感器网络的环签名方案

Wireless Sensor Network (WSN) nodes are severely limited by their power, communication band-width, and storage space, and the traditional signature algorithm is not suitable for WSN environments. In this paper, we present a ring signature scheme de-signed for WSNs. In this scheme, all of the wireless sensor nodes are divided into several sub-groups and the sub-group nodes are used to generate the signature instead of the WSN cluster nodes. This scheme can effectively avoid the single node failure problem, and it also has a high availability. All nodes are free to sign their own message, and the nodes that generate signatures can simultaneously calculate their own part of the signature, meeting the distributed parallel com-puting requirements. Compared with the traditional ring signature, this scheme reduces the energy con-sumption, and therefore is very suitable for WSNs.     

一种基于身份的代理可验证加密签名方案

A Verifiably Encrypted Signature (VES) plays an essential role in the construction of a fair data exchange. The paper proposes an Identity-based Proxy Verifiably Encrypted Signature (IPVES) to combine the advantages of a proxy sig-nature and a VES in order to delegate the signing capability of the VES of an entity called the original signer to another entity, called the proxy signer. In this IPVES scheme, the original signer delegates his/her signing capability to the proxy signer. The proxy signer issues a signature by using a proxy signing key, encrypts the signature under a desig-nated public key, and subsequently convinces a ver-ifier that the resulting ciphertext contains such a signature. We prove that the proposed IPVES scheme is secure in a random oracle model under the computational Diffie-Hellman assumption.     

并行密钥隔离聚合签名

为了应对聚合签名中的密钥泄露问题,将并行密钥隔离机制扩展到聚合签名系统中,给出了并行密钥隔离聚合签名的概念。在给出的形式化定义和安全模型的基础上,提出了第一个并行密钥隔离聚合签名方案,并在随机预言模型下证明了方案的安全性。所提出的方案满足密钥隔离性、强密钥隔离性和安全密钥更新等性质,特别在签名验证方面具有较高的效率。引入的两个协助器交替帮助用户进行临时私钥更新,增强了系统防御密钥泄露的能力。     

Secure and efficient anonymous proxy signature scheme in the random oracle model

Anonymous proxy signature scheme can provide the privacy protection for the proxy signer. Recently, Yu et al. proposed an anonymous proxy signature, which can be viewed as the organic combination of proxy signature and ring signature. However, the efficiency is low. In this paper, we propose an efficient and secure proxy signature with the properties of anonymity and traceability, and it is provably secure in the random oracle model. Compared with Yu et al.＇s scheme, the scheme has higher efficiency.     

Stateless Transitive Signature Schemes

A new practical method is introduced to transform the stateful transitive signature scheme to stateless one with-out the loss of security.According to the approach,two concrete stateless transitive signature schemes based on Factoringand RSA are presented respectively.Under the assumption of the hardness of factoring and one-more-RSA-inversion prob-lem,both two schemes are secure under the adaptive chosen-message attacks in random oracle model.