A Verifiable Multi-Secret Sharing Scheme Based on Hermite Interpolation

A threshold scheme, which is introduced by Shamir in 1979, is very famous as a secret sharing scheme. We can consider that this scheme is based on Lagrange＇s interpolation formula. A secret sharing scheme has one key. On the other hand, a multi-secret sharing scheme has more than one key, that is, a multi-secret sharing scheme has p （〉_ 2） keys. Dealer distribute shares of keys among n participants. Gathering t （〈 n） participants, keys can be reconstructed. Yang et al. （2004） gave a scheme of a （t, n） multi-secret sharing based on Lagrange＇s interpolation. Zhao et al. （2007） gave a scheme of a （t, n） verifiable multi-secret sharing based on Lagrange＇s interpolation. Recently, Adachi and Okazaki give a scheme of a （t, n） multi-secret sharing based on Hermite interpolation, in the case ofp 〈 t. In this paper, we give a scheme ofa （t, n） verifiable multi-secret sharing based on Hermite interpolation.

A verifiable essential secret image sharing scheme based on HLRs(VESIS-(t,s,k,n))

In traditional secret image sharing schemes,a secret image is shared among shareholders who have the same position.But if the shareholders have two different positions,essential and non‐essential,it is necessary to use essential secret image sharing schemes.In this article,a verifiable essential secret image sharing scheme based on HLRs is proposed.Shareholder's share consists of two parts.The first part is produced by the shareholders,which prevents the fraud of dealers.The second part is a shadow image that is produced by using HLRs and the first part of share.The verification of the first part of the shares is done for the first time by using multilinear and bilinear maps.Also,for verifying shadow images,Bloom Filters are used for the first time.The proposed scheme is more efficient than similar schemes,and for the first part of the shares,has formal security.

Verifiable Secret Redistribution for Proactive Secret Sharing Schemes

A new scheme to verifiably redistribute a secret from the old to new shareholders without reconstruction of the secret is presented in this paper. The scheme allows redistribution between different access structures and between different threshold schemes. A point worth mentioning is that this verifiable secret redistribution (VSR) scheme can identify dishonest old shareholders during redistribution without any assumption. A certain technique is adopted to verify the correctness of the old shares of the secret. As a result, the scheme is very efficient. It can be applied to proactive secret sharing (PSS) schemes to construct more flexible and practical proactive secret sharing schemes.

Information-Theoretic Secure Verifiable Secret Sharing over RSA Modulus

The well-known non-interactive and information-theoretic secure verifiable secret sharing scheme presented by Pedersen is over a large prime. In this paper, we construct a novel non-interactive and information-theoretic verifiable secret sharing over RSA （Rivest, Shamir, Adleman） modulus and give the rigorous security proof. It is shown how to distribute a secret among a group such that any set of k parties get no information about the secret. The presented scheme is generally applied to constructions of secure distributed multiplication and threshold or forward-secure signature protocols.

ASYNCHRONOUS BYZANTINE AGREEMENT PROTOCOL BASED ON VERIFIABLE SIGNATURE SHARING

An ([n/3]-1)-resilient Asynchronous Byzantine Agreement Protocol (ABAP) that combines verifiable signature sharing and random secret sharing is proposed. The protocol works in the asynchronous network environment and produces Byzantine agreement within a fixed expected number of computational rounds. The correctness of the protocol is proved in theory.

Verifiable Secret Sharing Scheme Based on the Plane Parametric Curve

Verifiable secret sharing is a special kind of secret sharing. In this paper, A secure and efficient threshold secret sharing scheme is proposed by using the plane parametric curve on the basis of the principle of secret sharing. And the performance of this threshold scheme is analyzed. The results reveal that the threshold scheme has its own advantage of one-parameter representation for a master key, and it is a perfect ideal secret sharing scheme. It can easily detect cheaters by single operation in the participants so that the probability of valid cheating is less than 1/p (where p is a large prime).

Bipartite Threshold Multi-Secret Sharing Scheme Based on Hypersphere

To address the problem that existing bipartite secret sharing scheme is short of dynamic characteristic, and to solve the problem that each participant can only use secret share once, this paper proposed a bipartite (n1+n2, m1+m2)-threshold multi-secret sharing scheme which combined cryptography and hypersphere geometry. In this scheme, we introduced a bivariate function and a coordinate function over finite field Zp to calculate the derived points of secret share, which can reconstruct the shared secrets by producing the intersection point of hypernormal plane and normal line on the hypertangent plane. At the initial stage the secret dealer distributes to each participant a secret share that can be kept secret based on the intractability of discrete logarithm problem and need not be changed with updating the shared secrets.Each cooperative participant only needs to submit a derived point calculated from the secret share without exposing this secret share during the process of reconstructing the shared secret. Analyses indicate that the proposed scheme is not only sound and secure because of hypersphere geometric properties and the difficulty of discrete logarithm problem, but also efficient because of its well dynamic behavior and the invariant secret share. Therefore, this bipartite threshold multi-secret sharing scheme is easy to implement and is applicable in practical settings.

Publicly Verifiable Distributed Proxy Blind Signature Scheme

In this present paper, we propose a new proxy blind signature scheme, which is publicly verifiable distributed. The algorithm uses the idea of secret sharing schemes to distribute original signer＇s ability and the power of the proxy signer, and ensure the property of publicly verifiable secret sharing schemes. A new concept ＂verifiable time period＂ is also introduced to reduce the time cost in the period of verifications and increases the efficiency of our scheme.

基于变色龙哈希和可验证秘密共享的联盟链修改方法

区块链具有去中心化、不可篡改、可追溯等特征。现有的联盟链系统在数据上链后会全程留痕,当出现敏感信息或恶意数据时无法处理,或处理后区块链分叉、中断。针对这些问题,提出一种基于变色龙哈希和可验证秘密共享的联盟链数据修改方法。首先,把变色龙哈希的陷门再分配给身份节点,从而将发起修改者与实际修改者进行隔离;其次,为保证再分配值的正确性,将不同时间周期变色龙哈希所对应的数据设为可验证数据,用验证节点上传承诺到可验证数据,并用提案节点通过承诺验证秘密共享值;最后,为防止节点作恶,提出基于奖励金机制的数据纠正方法提高节点纠正作恶的积极性,降低作恶的可能。在中山大学区块链与智能金融研究中心InPlusLab开发的DApps数据集上进行实验的结果表明:当恶意节点数30个时,所提方法相较于用传统变色龙哈希修改联盟链数据的方法在处理恶意节点的效率方面提高了44.1%;当恶意数据量达到30条时,在处理恶意数据的时间上缩短了53.7%。

抵抗不诚实参与者欺骗攻击的可验证渐进式秘密图像分享

当前渐进式秘密图像分享方案中并没有考虑不诚实参与者的作弊攻击,这使得不诚实的参与者可以利用虚假阴影图像进行欺骗攻击.为了防止后续渐进式重建失败,本文通过将像素的位平面划分为两部分,并使用拉格朗日插值算法以及视觉密码学方案来解决这个问题.通过伪随机数来确定像素位平面的滑动窗口,并通过筛选操作将认证信息嵌入到该滑动窗口中来实现认证能力.除此之外,不同的位平面划分策略可以产生不同的渐进式重建效果,可以实现更加灵活的渐进式重建.理论分析和实验结果表明方案的有效性.

一种基于Schnorr签名的区块链预言机改进方案

区块链预言机是一种为上链数据提供可信保障的中间件,可以有效解决链上链下数据传输的信任问题。当前预言机方案大多存在成本高、容错率低、密钥泄露、数据泄漏、签名失效等问题,为此,提出一种基于Schnorr门限聚合签名的区块链预言机改进方案。通过引入可验证随机函数生成可验证随机数,解决签名过程中随机数重复或能够被预测而导致的密钥泄露问题;通过引入可验证秘密分享技术,解决签名过程中密钥分发者作恶而导致的签名失效问题。预言机通过验证密钥碎片检测密钥分发者是否作恶,验证结束后向预言机智能合约发送验证结果,当预言机智能合约收到t个验证失败的结果时向所有预言机发送消息,达成一致性共识后重启签名。在数据提交阶段,只有预言机身份验证通过时才允许其提交,以防止签名过程中的数据泄露。同时,设置预言机信誉与激励机制,保证信誉较好的预言机在有效时间内参与签名并获得奖励。实验结果表明,在预言机节点数量为50、密钥分发者作恶且恶意预言机占预言机群体总数近50%时,该方案消耗的总时间不超过200 ms,gas消耗量不超过5×10~5 wei,可以有效实现可信数据上链。

基于格的最优轮数口令认证秘密共享协议

口令认证秘密共享将口令认证和秘密共享相结合,是一个贴合实际用户需求的分布式方案。该协议允许一个用户在多个服务器间共享秘密,并且只需要记忆一个简短口令即可在后续同时完成身份验证以及秘密恢复。协议安全性保证只要敌手控制的服务器不超过阈值,敌手就不能从协议中窃取任何有关口令和秘密的信息。口令认证秘密共享方案最初基于离散对数及其变体的假设,不能抵抗量子攻击,因此找到量子安全的构造成为亟需解决的问题。ROY等人提出一种恶意安全且量子安全的构造,但其通信轮数并非最优,在有恶意敌手干扰的情况下,轮数甚至不再是常数。针对轮数优化问题,文章利用可验证不经意伪随机函数原语,给出了基于格的最优轮数的量子安全构造并严格证明了其安全性。此外,协议保证多数诚实服务器场景时,诚实用户一定能在最优轮数内成功恢复正确的秘密,具有很强的鲁棒性。

一种基于STSS的可验证秘密分享方案

针对秘密分享体制下非诚实分发者提供错误份额无法追责的问题,提出了一种基于STSS的可验证秘密分享方案来提升不诚实参与者的检测能力.STSS方案首先让分发者通过Feldman秘密分享方案将主秘密分割成n份,所得子秘密使用SM2算法对其进行签名;其次,所得签名值(r,s)采用TEA算法进行加密得到最终份额;最后,针对秘密分享体制下非诚实分发者提供错误份额无法追责的问题,方案使用双重验证,接收者在收到分享份额后通过对称密钥解密得到签名值,对比分发者公钥,保证其在传输和存储过程中未受到篡改.需要使用主秘密时,t(t<n)位接收者参与验证秘密重构可恢复原始秘密.方案在随机预言机模型下证明了安全性,通过仿真实验表明:该方案在给定门限值和子秘密数量下运算效率较高.

一种可验证的渐进式多秘密图像共享方案

为了提高秘密图像共享方案的效率以及安全性,提出了一种可验证的渐进式多秘密图像共享方案。秘密图像共享中,通过生成的哈希值来进行秘密图像的验证。方案的恢复过程中,参与者的数量达到设定门限时可以恢复出第一张秘密图像;随着参与者的数量增多,其他秘密图像依次恢复出来,直至所有的秘密图像全部恢复出来。通过实验对比分析,所提出的方案能够对多秘密图像进行共享并验证,从而提高了秘密图像共享的效率。

A New Rational Secret Sharing Scheme

In this paper,we propose a new approach for rational secret sharing in game theoretic settings.The trusted center is eliminated in the secret reconstruction phase.Every player doesn’t know current round is real round or fake round.The gain of following the protocol is more than the gain of deviating,so rational player has an incentive to abide the protocol.Finally,every player can obtain the secret fairly.Our scheme is verifiable and any player’s cheating can not work.Furthermore the proposed scheme is immune to backward induction and satisfies resilient equilibrium.No player of the coalition C can do better,even if the whole coalition C cheats.Our scheme can withstand the conspiracy attack with at most m-1 players.

Protected Fair Secret Sharing Based Bivariate Asymmetric Polynomials in Satellite Network

Verifiable secret sharing mainly solves the cheating behavior between malicious participants and the ground control center in the satellite network.The verification stage can verify the effectiveness of secret shares issued by the ground control center to each participant and verify the effectiveness of secret shares shown by participants.We use a lot of difficult assumptions based on mathematical problems in the verification stage,such as solving the difficult problem of the discrete logarithm,large integer prime factorization,and so on.Compared with other verifiable secret sharing schemes designed for difficult problems under the same security,the verifiable secret sharing scheme based on the Elliptic Curve Cryptography(ECC)system has the advantages of less computational overhead and shorter key.At present,the binary polynomial is a single secret scheme and cannot provide effective verification.Therefore,based on a Protected Verifiable Synchronous Multi Secret Sharing(PVS-MSS)scheme,this paper is designed based on bivariate asymmetric polynomials.The advanced verifiable attribute is introduced into the Protected Secret Sharing(PSS)scheme.This paper extends the protected synchronous multi-secret sharing scheme based on bivariate polynomial design.The ECC system constructs the security channel between the ground control center and participants and constructs the verification algorithm.Through the verification algorithm,any participant can verify the consistency and effectiveness of the secret shadow and secret share received from other participants or presented by the secret distribution center.Therefore,no additional key agreement protocol is required;participants do not need to negotiate the session key for encryption;the secret share polynomial can generate the session key between participants and speed up the secret reconstruction process.The verification stage has lower computational complexity than the verifiable scheme constructed by Rivest Shamir Adleman (RSA) and other encryption methods. Chinese Remainder Theorem (CRT)is used to update the secret shadow. The secret shadow does not need to beupdated with the change of the scheme shared secret, and the public valueupdate efficiency is higher. Reduce the complexity of sharing secret updatesin a synchronous multi-secret sharing scheme.

NEW SECRET SHARING SCHEME BASED ON LINEAR CODE

A secret sharing system can be damaged when the dealer cheating occurs.In this paper,two kinds of secret sharing schemes based on linear code are proposed.One is a verifiable scheme which each participant can verify his own share from dealer's distribution and ensure each participant to receive valid share.Another does not have a trusted center,here,each participant plays a dual-role as the dealer and shadow(or share) provider in the whole scheme.

Efficient Data Integrity Using Enhanced Secret Sharing Scheme for MANET

Mobile Ad Hoc Networks consist of nodes which are wireless and get organized based on the transmission requirement. These nodes are mobile nodes, so they communicate with each other without any fixed access point. This type of network faces several attacks because of its mobility nature. In MANET, black hole attacks may cause packet dropping or misrouting of packets during transmission from sender to receiver. This may lead to performance degradation in the network. To surmount this issue, we propose the modified secret sharing scheme to provide the data protection from unauthorized nodes, consistency of data and genuineness. In this algorithm, initially the identification of black hole attacks is achieved and followed by data protection from malicious nodes and also this scheme checks for the reality of the data. Here, we detect the misbehaviour that is dropping or misrouting using verifiable secret sharing scheme. The proposed algorithm achieves the better packet delivery ratio, misbehaviour detection efficiency, fewer packets overhead and end-to-end delay than the existing schemes. These can be viewed in the simulation results.

基于可验证秘密共享的多关键词可搜索加密方案

可搜索加密技术在云存储技术快速发展的环境下已经被广泛应用于数据安全与个人信息保护的实施办法中,并作为研究热点被国内外众多学者关注。密码体制的安全性依赖密钥的保密,然而目前大多可搜索加密方案都需要用户自行管理密钥,存在密钥泄露和遗失的风险,影响加密方案的安全性,同时也限制了需要使用不同设备的用户。文章针对可搜索加密的密钥管理问题,基于可验证秘密共享提出了一种密钥可重构的多关键词可搜索加密方案,用户只需依赖自己的生物特征和预设口令即可完成数据的外包和检索,摆脱了自行管理密钥的困扰。方案满足选择关键词不可区分和身份认证两个安全属性,确保只有口令正确且生物特征与模板足够接近的情况下才能完成数据的外包和检索,用户特征的正确性由服务器端计算并验证,且无法得到关于用户的原始生物特征、密钥和关键词等隐私信息。

DYNAMIC AND VERIFIABLE SECRET SHARING AMONG WEIGHTED PARTICIPANTS

A secret sharing scheme permits a secret to be shared among participants in such a way that only qualified subsets of participants can recover the secret. Secret sharing is useful in management of cryptographic keys. Based on identity, we analyze the secret sharing scheme among weighted participants. Then we present a dynamic scheme about secret sharing among weighted participants. At last, we analyze the secret sharing scheme among weighted participants, which can make all weighted participants verifiable and dynamic.