NTRU格上高效的身份基线性同态签名方案

针对现有的格上身份基线性同态签名方案密钥存储量大、结构复杂导致方案实际运行效率相对偏低的问题,提出了一个NTRU(Number Theory Research Unit)格上高效的身份基线性同态签名方案。首先在密钥生成阶段利用NTRU密钥生成算法产生主密钥,接着采用格基委派算法给出身份签名私钥,最后运行NTRU格上原像抽样算法产生出线性同态签名。对方案的安全性证明与性能分析结果表明,新方案满足正确性,具有弱内容隐私性。在随机预言机模型下,该方案在小整数解问题困难性条件下满足适应性选择身份和选择消息的存在性不可伪造性。同时,由于采用NTRU格的特殊结构,新方案在密钥量与运行效率方面与已有方案相比较均具有显著的优势,这对于计算资源受限环境的同态认证中具有重要的应用价值。     

一种基于混沌的量子身份认证

提出了一种新的基于混沌的量子身份认证方案,该方案将混沌系统对初值条件和参数的极度敏感性及混沌序列的良好伪随机性与量子密码的绝对安全性结合在一起,能够有效地抵抗多次身份认证中由于有限精度导致的混沌特性退化而造成对混沌系统初值和参数的攻击。在方案的实现过程中,利用量子隐形传态原理,解决了多次身份认证中出现的混沌迭代异步问题,实现了每一次身份认证中双方的同步,从而实现了“一次一密”的量子身份认证。整个身份认证过程实现简单,具有动态性和可证明的安全性。     

对一个格基身份签名方案的分析和改进

首先分析了Liu等人2013年给出的一个格基身份签名（IBS）方案在安全性证明中存在的问题,进而说明方案的证明达不到作者所宣称的选择身份和自适应选择消息攻击下的强不可伪造性。其次,使用Boyen10签名技术（PKC 2010）对此方案中签名算法进行改进,并在标准模型下证明了改进方案在选择身份和自适应选择消息攻击下具有强不可伪造性的安全性质。另外,对比分析了改进的方案和其他IBS方案的效率和安全性。     

无陷门格基签密方案

现有的格基签密方案以陷门产生算法和原像取样算法为核心算法。但是,这两个算法都很复杂,运算量较大,严重影响格基签密方案的执行效率。该文运用无陷门格基签名及其签名压缩技术,结合基于带错学习问题的加密方法,提出第1个基于格理论的、不依赖于陷门产生算法和原像取样算法的签密方案。方案在带错学习问题和小整数解问题的难解性假设下,达到了自适应选择密文攻击下的不可区分性和自适应选择消息攻击下的不可伪造性。方案在抗量子攻击的同时,保证了较高的执行效率。     

格上基于身份的增量签名方案

将基于身份的密码学思想应用于增量签名中,提出了基于身份的增量签名概念,并基于格上困难问题设计了一种基于身份的增量签名方案.在标准的小整数解困难假设下,所提方案在标准模型下满足适应性选择身份和选择消息攻击下的不可伪造性.理论分析和实验结果表明,所提增量签名算法比标准签名算法具有更高的计算效率.     

协议组合逻辑安全的4G无线网络接入认证方案

针对4G无线网络中移动终端的接入认证问题,基于自证实公钥系统设计了新的安全接入认证方案,并运用协议演绎系统演示了该方案形成的过程和步骤,用协议组合逻辑对该方案的安全属性进行了形式化证明.通过安全性证明和综合分析,表明该方案具有会话认证性和密钥机密性,能抵御伪基站攻击和重放攻击,并能提供不可否认服务和身份隐私性,同时提高了移动终端的接入效率     

基于认证的高效公钥加密算法

 2003年,Gentry提出基于认证的公钥加密方案.在基于认证的公钥加密方案中,第三方对认证申请者的公钥和/或身份进行签名,并将签名作为认证发送给申请者,申请者保存该认证作为解密时的部分私钥.接收方对密文解密需要同时拥有第三方对其公钥和/或身份的认证和接收方公钥对应的私钥,因此基于认证的加密方案同时具备基于身份加密方案的公钥可认证性和传统公钥方案中的私钥免撤销性.本文提出一种高效、紧凑的基于认证的公钥混合加密算法,新算法能在非随机预言机模型下被证明满足选择密文攻击安全.     

基于纠缠辅助码的量子模糊承诺和生物认证

本文针对经典模糊承诺体制不能有效抵抗量子算法攻击的问题,在纠缠辅助量子纠错码的基础上,结合量子哈希构造一类新的量子模糊承诺体制.利用无需自对偶约束的量子纠错码空间构建模糊承诺集产生承诺阶段所需的码字,并对其施加用于模糊证明的加噪变换,有效抵抗量子傅立叶取样攻击;提出一种量子哈希,对随机量子序列进行混淆扩散后加密,实现信息论意义上的一次一密安全.据此构建的量子模糊承诺体制可有效抵抗量子图灵机攻击.该文还给出了基于量子模糊承诺的挑战响应生物认证方案,分别对量子模糊承诺和生物认证方案在量子计算环境下的安全性作了分析,证明了其安全性和有效性.     

基于NTRU的全同态加密方案

本文提出一种基于公钥密码体制（Number Theory Research Unit,NTRU）选择明文攻击（Chosen Plaintext Attack,CPA）可证明安全的全同态加密方案.首先,对NTRU的密钥生成算法进行改进,通过格上的高斯抽象算法生成密钥对,避免了有效的格攻击,同时,没有改变密钥的分布.然后,基于改进的NTRU加密算法,利用Flattening技术,构造了一个全同态加密体制,并在标准模型下证明方案是选择明文攻击不可区分性IND-CPA安全的.     

一种基于光子偏振旋转的量子身份认证方案

实际的量子密钥分发过程中,传输损耗和探测器的效率都直接影响密钥的产生效率。量子身份认证需要通信双方保证认证信息的完整性。针对以上问题,提出了一种基于光子偏振旋转的量子身份认证协议,利用对认证信息的重复编码解决传输损耗问题。考虑到协议的安全性,该协议在相邻的有效认证量子态间编入随机态。安全性分析表明该协议可成功抵御截取重发攻击以及光子数劈裂攻击。在此基础上,设计了现有技术条件下可操作的认证系统方案,考虑了传输损耗和探测效率,具有实用意义。     

移动漫游中强安全的两方匿名认证密钥协商方案

由于低功耗的移动设备计算和存储能力较低,设计一种高效且强安全的两方匿名漫游认证与密钥协商方案是一项挑战性的工作.现有方案不仅计算开销较高,而且不能抵抗临时秘密泄露攻击.针对这两点不足,提出一种新的两方匿名漫游认证与密钥协商方案.在新方案中,基于Schnorr签名机制,设计了一种高效的基于身份签密算法,利用签密的特性实现实体的相互认证和不可追踪;利用认证双方的公私钥直接构造了一个计算Diffie-Hellman（Computational Diffie-Hellman,CDH）问题实例,能抵抗临时秘密泄露攻击.新方案实现了可证明安全,在eCK（extended Canetti-Krawczyk）模型基础上,探讨两方漫游认证密钥协商方案安全证明过程中可能出现的情形,进行归纳和拓展,并给出新方案的安全性证明,其安全性被规约为多项式时间敌手求解椭圆曲线上的CDH问题.对比分析表明：新方案安全性更强,需要实现的算法库更少,计算和通信开销较低.新方案可应用于移动通信网络、物联网或泛在网络,为资源约束型移动终端提供漫游接入服务.     

Grid authentication from identity-based cryptography without random oracles

As a critical component of grid security, secure and efficient grid authentication needs to be well addressed. However, the most widely accepted and applied grid authentication is based on public key infrastructure （PKI） and X.509 certificates, which make the system have low processing efficiency and poor anti-attack capability. To accommodate the challenge of grid authentication, this article aims at designing a secure and efficient method for grid authentication by employing identity-based cryptography （IBC）. Motivated by a recently proposed secure and efficient identity-based encryption （IBE） scheme without random oracles, an identity-based signature （IBS） scheme is first proposed for the generation of private key during grid authentication. Based on the proposed IBS and the former IBE schemes, the structure of a novel grid authentication model is given, followed by a grid authentication protocol described in detail. According to the theoretical analysis of the model and the protocol, it can be argued that the new system has improved both the security and efficiency of the grid authentication when compared with the traditional PKI-based and some current IBC-based models.     

A Strong Authentication Scheme with User Privacy for Wireless Sensor Networks

Wireless sensor networks (WSNs) are used for many real‐time applications. User authentication is an important security service for WSNs to ensure only legitimate users can access the sensor data within the network. In 2012, Yoo and others proposed a security‐performance‐balanced user authentication scheme for WSNs, which is an enhancement of existing schemes. In this paper, we show that Yoo and others' scheme has security flaws, and it is not efficient for real WSNs. In addition, this paper proposes a new strong authentication scheme with user privacy for WSNs. The proposed scheme not only achieves end‐party mutual authentication (that is, between the user and the sensor node) but also establishes a dynamic session key. The proposed scheme preserves the security features of Yoo and others' scheme and other existing schemes and provides more practical security services. Additionally, the efficiency of the proposed scheme is more appropriate for real‐world WSNs applications.     

一种NTRU格上基于身份全同态加密体制设计

全同态加密可以用来解决云计算环境中的隐私保护问题,然而现有体制具有系统参数大、效率低的缺点.针对现有攻击技术,首先设计了一种高效的NTRU格上的基于身份公钥加密体制,无需借助额外的安全性假设,具有更高的安全性和更小的系统参数.之后,基于近似特征向量技术,构造了一种高效的全同态加密转化方式.通过将以上两种方法结合,给出了一种高效的基于身份全同态加密体制.和现有体制相比,除了不需要计算密钥、实现了真正意义上的基于身份特性以外,还减小了密钥、密文尺寸,提高了计算和传输效率.     

ID-based authentication scheme combined with identity-based encryption with fingerprint hashing

Current identity-based （ID） cryptosystem lacks the mechanisms of two-party authentication and user＇s private key distribution. Some ID-based signcryption schemes and ID-based authenticated key agreement protocols have been presented, but they cannot solve the problem completely. A novel ID-based authentication scheme based on ID-based encrypfion （IBE） and fingerprint hashing method is proposed to solve the difficulties in the IBE scheme, which includes message receiver authenticating the sender, the trusted authority （TA） authenticating the users and transmitting the private key to them. Furthermore, the scheme extends the application of fingerprint authentication from terminal to network and protects against fingerprint data fabrication. The fingerprint authentication method consists of two factors. This method combines a token key, for example, the USB key, with the user＇s fingerprint hash by mixing a pseudo-random number with the fingerprint feature. The security and experimental efficiency meet the requirements of practical applications.     

<Emphasis Type="Italic">EIAS-CP:</Emphasis> new efficient identity-based authentication scheme with conditional privacy-preserving for VANETs

In VANETs, vehicles broadcast traffic-related messages periodically according to Dedicated Short Range Communication protocol. To ensure the reliability and integrity of messages, authentication schemes are involved in VANETs. As traffic-related messages are time-sensitive, they must be verified and processed timely, or it may cause inestimable harm to the traffic system. However, the OBUs and the RSUs are limited in computation ability and cannot afford vast messages’ verification. Recently, some identity-based authentication schemes using bilinear pairing have been proposed to improve the efficiency of message verification for VANETs. Nevertheless, the bilinear pairing is not suited for VANETs due to its complex operations. The design of an efficient and secure authentication scheme with low computation cost for VANETs still is a rewarding challenge. To settle this challenge, a new efficient identity-based authentication scheme is proposed in this paper. The proposed scheme ensures reliability and integrity of messages and provides conditional privacy-preserving. Compared with the most recent proposed authentication schemes for VANETs, the computation costs of the message signing and verification in the proposed scheme reduce by 88 and 93 % respectively, while security analysis demonstrates that our proposed scheme satisfies all security and privacy requirements for VANETs.     

VoIP网络基于签密的安全机制的研究与实现

提出了一种高效的基于身份的可用于多域的签密方案并引申出相应的数字签名方案,然后在该方案的基础上提出了一种适用于VoIP网络环境的安伞机制,该机制避免了基于传统PKI的安全机制的诸多弊端,实现了跨域的身份认证与消息的机密传输.经过分析以及实现验证:该机制与已有的安全机制有很好的兼容性,且不降低原机制的安全性及有效性,同时解决了HTTP摘要认证下的单向认证以及预共享密钥问题,并消除了S/MIME基于证书认证和SRTP不提供密钥协商的不足.     

An ID‐based mutual authentication with key agreement protocol for multiserver environment on elliptic curve cryptosystem

Mutual authentication is used to validate the legitimacy of a remote login user and a server. Conventional user authentication protocols are suited to solve the privacy and security problems for the single client/server architecture environment. However, the use of computer networks and information technology has grown spectacularly. More and more network architectures are used in multi‐server environments. Recently, several authentication schemes for multi‐server environments have been proposed. However, the performance of these schemes is not suitable for applications. To improve the performance, we propose a new ID‐based mutual authentication protocols for multi‐server environment without bilinear pairings. We also show that the proposed scheme is provable secure in the random oracle model. Copyright © 2012 John Wiley & Sons, Ltd.     

Efficient and secure message authentication scheme for VANET

A new efficient identity-based message authentication scheme for VANET was proposed. The proposed scheme decreased the complexity of cryptographic operations on signature by using elliptic curve cryptosystem (ECC) to construct authentication protocol without bilinear pairing and provided the function of conditional privacy-preserving. Security analysis demonstrated that the proposed scheme satisfies all security and privacy requirements for VANET. Per-formance analysis show that compared with the most recent proposed schemes the proposed scheme decreases the com-putation cost and communication cost.