A provably secure proxy signature scheme from bilinear pairings

A proxy signature allows an entity, called original signer, to delegate its signing power to another entity, called proxy signer, to sign messages on its behalf. Proxy signatures have many practical applications and are very important cryptographic protocol. In this paper, we propose an efficient proxy signature scheme from bilinear pairings. We prove it secure in the random oracle model and analyze computation cost of our scheme. Our scheme satisfies all the properties required for proxy signatures.     

Construction of proxy blind signature scheme based on multi-linear transform

A general method of constructing proxy blind signature is proposed based on multilinear transform. Based on this method, the four proxy blind signature schemes are correspondently generated with four different signature equations, and each of them has four forms of variations of signs. Hence there are sixteen signatures in all, and all of them are proxy stronglyblind signature schemes. Furthermore, the two degenerated situations of multi-linear transform are discussed. Their corresponding proxy blind signature schemes are shown, too. But some schemes come from one of these degenerate situations are proxy weakly-blind signature scheme. The security for proposed scheme is analyzed in details, The results indicate that these signature schemes have many good properties such as unforgeability, distinguish-ability of proxy signature, non-repudiation and extensive value of application etc.     

Identity-based key-insulated proxy signature

In proxy signature schemes, the proxy signer B is permitted to produce a signature on behalf of the original signer A. However, exposure of proxy signing keys can be the most devastating attack on a proxy signature scheme since any adversary can sign messages on behalf of the proxy signer. In this paper, we applied Dodis, et al.’s key-insulation mechanism and proposed an Identity-Based (ID-based) Key-Insulated Proxy Signature (IBKIPS) scheme with secure key-updates. The proposed scheme is strong key-insulated and perfectly key-insulated. Our scheme also supports unbounded period numbers and random-access key-updates.     

一个量子代理弱盲签名方案

代理盲签名在电子支付系统、电子投票系统、移动代理系统和网络安全等方面有着广泛的应用.基于EPR (Einstein–Padolsky–Rosen)对的纠缠相干性和可控量子隐形传态,提出了一种量子代理弱盲签名方案.不同于经典的基于计算复杂性的代理盲签名方案,本方案利用量子力学的物理特性来实现消息盲化、签名及验证,因而保证了消息所有者的匿名性和无条件安全性.     

一种门限代理盲签名方案

以电子选举为例,在盲签名的基础上将双线性对作为工具,结合代理签名和门限签名,提出了基于双线性对的门限代理盲签名方案。详细分析了方案的实现过程,并对该方案的有效性、安全性、盲性和方案效率进行分析论证。通过分析及论证,得出该方案的实现过程简单,效率较高。     

高效的基于ID的无证书签名方案

通过利用gap diffie-hellman(GDH)群,提出了一种高效的基于ID的无证书签名方案,该方案通过将2个部分公钥绑定相同的一个ID,从而解决了密钥托管问题.在这个方案中,私钥生成中心(PKG,private key generator)不能够伪造合法者的签名,因为只能生成一部分私钥,其安全性依赖于CDHP(computational diffie-hellman problem).在随机预言机模型下,新方案被证明能够抵抗适应性选择消息攻击和ID攻击下的存在性伪造.该方案不仅解决了密钥托管问题而且与许多已有的方案相比具有较高的效率.     

A secure proxy signature scheme based on elliptic curve cryptosystem

Proxy signature is a special digital signature which enables a proxy signer to sign messages on behalf of the original signer. This paper proposes a strongly secure proxy signature scheme and a secure multi-proxy signature scheme based on elliptic curve cryptosystem. Contrast with universal proxy signature schemes, they are secure against key substitute attack even if there is not a certificate authority in the system, and also secure against the original signer＇s forgery attack. Furtherlnore, based on the elliptic curve cryptosystem, they are more efficient and have smaller key size than other system. They can be used in electronics transaction and mobile agent environment.     

可证安全的有效代理签名方案

针对固定维数的格基委托算法或格上基于盆景树生成的代理签名方案中私钥和签名的长度均过大的问题,提出一种较小尺寸的代理签名方案。该方案对随机预言机进行了合并优化,并使用一个更小范数但是向量盲化的消息,从而控制代理签名私钥的维数,其安全性基于格上最短向量问题和小整数解问题的困难性,并且满足代理签名方案所有的安全性要求。与现有方案相比,该方案有效地减小了代理签名私钥和代理签名的长度,使代理私钥长度与原始签名用户私钥长度相当。     

一种安全的匿名代理数字签名方案

提出了具有新特点的代理签名方案:匿名性、可追踪性和不可伪造性,在该方案中,代理签名者身份对验证者来说是不可见的,签名出现争议时,验证者可以借助原始签名者确定代理签名者的身份;可以抵抗伪造攻击。分析结果表明,改进后的方案是安全的。     

无双线性对的基于身份的在线/离线门限签名方案

为了减少公钥密码体制中证书管理带来的开销和提高在线/离线门限签名方案的性能,利用分布式密钥生成协议和可验证秘密共享协议,提出了一种基于身份的在线/离线门限签名方案,并在离散对数假设下证明了新方案满足顽健性和不可伪造性。分析结果表明,新方案避免了传统公钥证书的管理问题和复杂的双线性对运算,大大降低了离线门限签名算法和签名验证算法的计算复杂度,在效率上优于已有的在线/离线门限签名方案。     

New ID-based group signature from pairings

We argue that traditional identity-based systems from pairings seem unsuitable for designing group signature schemes due to the problem of key escrow. In this paper we first propose new ID-based public key systems without trusted PKG （Private Key Generator） from bilinear pairings, In our new ID-based systems, if the dishonest PKG impersonates an honest user to communicate with others, the user can provide a proof of treachery of the PKG afterwards, which is similar to certificate-based systems. Therefore, our systems reach the Girault＇s trusted level 3. We then propose a group signature scheme under the new ID-based systems, the security and performance of which rely on the new systems. The size of the group public key and the length of the signature are independent on the numbers of the group.     

标准模型下基于身份的高效动态门限代理签名方案

基于身份的门限代理签名方案大都是在随机预言模型下进行安全证明,并且方案中每个代理人的代理签名密钥在有效期内都是固定不变的。在已有的基于身份的签名方案基础上,利用可公开验证秘密分享技术提出了一个在标准模型下可证安全的基于身份的(t,n)-动态门限代理签名方案。方案中代理人的代理签名密钥可以定期更新,而且代理签名验证过程只需要常数个双线性对运算,因此方案具有更好的动态安全性和较高的效率。     

基于二元哈希树的密钥隔离代理签名方案

给出基于二元哈希树的密钥隔离代理签名方案,该方案可以降低了移动代理滥用攻击和密钥泄漏产生的危害。通过分析,该方案的代理签名的密钥长度是固定的,与隔离时间片段无关。相比之前的密钥隔离方案,方案只需要额外的O(TN)次Hash操作和额外的|q|比特存储量。同时,方案安全性可以证明是基于在随机预言机模型下所用的DSS签名方案的安全性。     

Ring proxy signatures

Proxy signatures have been used to enable the transfer of digital signing power within some context and ring signatures can be used to provide the anonymity of a signer. By combining the functionalities of proxy signatures and ring signatures, this paper introduces a new concept, named ring proxy signature, which is a proxy signature generated by an anonymous member from a set of potential signers. The paper also constructs the first concrete ring proxy signature scheme based on the provably secure Schnorr＇s signatures and two ID-based ring proxy signature schemes. The security analysis is provided as well.     

Certificateless signature and blind signature

Certificateless public key cryptography is a new paradigm introduced by Al-Riyami and Paterson. It eliminates the need of the certificates in traditional public key cryptosystems and the key escrow problem in IDentity-based Public Key Cryptography （ID-PKC）. Due to the advantages of the certificateless public key cryptography, a new efficient certificateless pairing-based signature scheme is presented, which has some advantages over previous constructions in computational cost. Based on this new signature scheme, a certificateless blind signature scheme is proposed. The security of our schemes is proven based on the hardness of computational Diffie-Hellman problem.     

A new multi-proxy signature from bilinear pairing

Proxy signatures are very useful tools when one needs to delegate his/her signing capability to other parties. In this paper, a new multi-proxy signature scheme is proposed. The new scheme is constructed from bilinear pairings using Boneh, Lynn, and Shacham＇s （BLS） short signatures. The proxy key for the proxy group is just a short signature on the proxy warrant generated by the original signer. Due to the use of short signatures, our scheme is not only efficient, but also satisfies all the security requirements of the strong proxy signature.     

前向安全的代理签名方案

将前向安全的概念引入到代理签名体制,提出了一个前向安全的代理签名方案。新方案能实现即使代理签名人的代理签名密钥被泄露,以前所产生的代理签名依然有效。另外,新方案可以对代理签名的有效时间进行控制。     

一种新的基于椭圆曲线的代理盲多重签名

为了实现电子商务和数字现金等活动中的匿名性和不可追踪性,对于代理多重签名方案,提出了一种新的基于椭圆曲线的签名方式:代理盲多重签名方案。在此数字签名方案的基础上,采用双线性对的签名和验证方式,提出了基于双线性对的代理盲多重签名方案,从而极大的提高了代理盲多重签名的安全性和实现速度。     

基于W态的量子代理盲签名

代理盲签名在电子投票系统、电子商务系统和网络环境等方面有着广泛的应用.综合考虑现实情形下的通信开销、量子操作复杂性、验证效率等相关因素,提出了一种基于量子W态相干性的量子代理盲签名方案.消息拥有者先将秘密盲化,代理签名者在经过授权后对盲化的消息进行有效签名.方案最大的优势是签名时仅仅需要单粒子测量,并不需要实施任何量子酉变换.此外,与其它主流方案相比,在验证签名和经典通信的效率上也获得了更好的效果.     

一种基于身份的代理盲签名方案

代理签名是一种非常有用的密码学工具，使用它，原始签名人能将其数字签名权力委托给代理签名人。在盲签名方案中，消息的内容对签名者是不可见的。签名被泄露后，签名者不能追踪其签名。代理签名和盲签名在实际中分别有着广泛的应用。文章结合两者的优点，利用椭圆曲线上的Weil对的双线性性，构造了一个基于身份的代理盲签名方案。