Undeniable Signature Research Articles

Cryptographic Signature Scheme for Mobile Edge Computing Using DLFP Over Semiring

The Undeniable Signature Scheme (USS) was first introduced by chaum and van in 1989. The advantage of the (USS) scheme is the signer’s co-operation during the verification process. In this paper, the Discrete Logarithm Problem with Factor Problem (DLFP) is introduced. It’s security and complexity is analyzed. Then, based on (DLFP), a key exchange protocol is given. An undeniable signature scheme based on DLFP over semiring is proposed along with illustration we have also given application of the proposed USS in Mobile Edge Computing (MEC). Then the proposed scheme’s security and complexity is examined.

Provably secure zero knowledge undeniable signature scheme over non-abelian group

Provably secure zero knowledge undeniable signature scheme over non-abelian group

Quantum Secure Undeniable Signature for Blockchain-Enabled Cold-Chain Logistics System

Data security and user privacy are two main security concerns in the cold-chain logistics system (CCLS). Many security issues exist in traditional CCLS, destroying data security and user privacy. The digital signature can provide data verification and identity authentication based on the mathematical difficulty problem for logistics data sharing in CCLS. This paper first established a blockchain-enabled cold-chain logistics system (BCCLS) based on union blockchain technology, which can provide secure data sharing among different logistics nodes and guarantee logistics data security with the untampered blockchain ledger. Meanwhile, a lattice-based undeniable signature scheme is designed to strengthen the security of logistics data and user privacy against quantum attacks. This scheme is based on the lattice assumption, which can provide anti-quantum security for BCCLS in the future quantum computer age. It also establishes the undeniable mechanism that guarantees that the actual signer cannot deny a valid signature. Then, security proof shows that this undeniable signature scheme is correct and safe, and an efficiency comparison shows that it is more efficient than other schemes in similar literature. The performance evaluations of transaction throughput and latency show that the proposed BCCLS is efficient and practical. This work can improve the security and efficiency of logistics data management and promote the reform and development of the logistics industry.

A Novel Undeniable (t, n)-Threshold Signature with Cheater Identification

A digital signature is one of the most widely used cryptographic primitives in asymmetry cryptography. According to the security requirements in different symmetry or asymmetry network models, various digital signatures have been developed in the literature. To protect the right of the signer, Chaum and Antrepen first introduced the concept of an undeniable signature, where interactive protocols are needed for the verification process. Besides, a signer can, also, perform a disavowal protocol to prove that they did not sign the message. On the other hand, threshold cryptography is, usually, used to protect the system from a single point of failure. In a (t,n)-threshold signature scheme, as long as t people in the group of n people participate, the signature can be smoothly signed. By combining these two features, an undeniable threshold signature enjoys the advantages from both sides. After our survey, we found that the existing undeniable threshold signature schemes are either insecure or apply impractical assumptions. Thus, in this manuscript, we aim at designing a novel and provably secure undeniable threshold signature scheme. The proposed scheme is formally proven to be unforgeable and invisible. Besides, our scheme supports cheater identification, which allows one to find the cheater, when a signing protocol fails. Moreover, the proposed scheme can be performed without the help of trusted third parties or secure cryptographic modules, which would be more practical when our scheme is deployed in real-world applications.

Lattice-based undeniable signature scheme

Lattice-based undeniable signature scheme

Рандомизированный аналог неоспоримой подписи Чаума - ван-Антверпена

We suggest an elliptic curve modification of the undeniable signature introduced by D. Chaum and H. van-Antwerpen. The signature generation algorithm is supplemented with a preliminary stage of randomization. For signature verification and disavowal protocols, two options are offered. Theorems showing that these protocols meet their purpose have been proven. A method for converting an undeniable signature into a regular digital signature is described, illustrated by the Schnorr electronic signature scheme as an example.

A new undeniable signature scheme on general linear group over group ring

The concept of undeniable signature scheme was put forward by D. Chaum and H. van Antwerpen in 1989. Such signature scheme requires the signer’s co-operation at the verification step which defends the signer against the verification of his/her signature by an unwanted entity. In this paper, we propose a new undeniable signature scheme in a non-abelian group over group ring whose security relies on the difficulty of solving Factorization with Discrete Logarithm Problem (FDLP).

Signatures of supersymmetry and a Lμ−Lτ gauge boson at Belle-II

We propose that the $\gamma + E \hspace{-.5em}/\;\:$ signal at the Belle-II will be a smoking gun for supersymmetry (SUSY) in the presence of a gauged $U(1)_{L_{\mu}-L_{\tau}}$ symmetry. A striking consequence of breaking the enhanced symmetry in the limit of degenerate (s)leptons is the nondecoupling of the radiative contribution of heavy charged sleptons, appearing in SUSY, to the $\gamma - Z^\prime$ kinetic mixing. The signal process, $e^+ e^- \rightarrow \gamma Z^\prime \rightarrow \gamma + E \hspace{-.5em}/\;\:$, is an outcome of this ubiquitous feature. We take into account the severe constraints on gauged $U(1)_{L_{\mu}-L_{\tau}}$ models by several low-energy observables and show that any significant excess in all but the highest photon energy bin would be an undeniable signature of such heavy scalar fields in SUSY coupling to $Z^\prime$. The number of signal events depends crucially on the logarithm of the ratio of stau to smuon mass in the presence of SUSY. In addition, the number is also inversely proportional to the $e^+-e^-$ collision energy, making a low-energy, high-luminosity collider like Belle-II an ideal testing ground for this channel. This process can probe large swathes of the slepton mass ratio vs the additional gauge coupling ($g_X$) parameter space. More importantly, it can explore the narrow slice of $M_{Z^{\prime}}-g_X$ parameter space still allowed in gauged $U(1)_{L_{\mu}-L_{\tau}}$ models for superheavy sparticles.

A Generic Framework for Accountable Optimistic Fair Exchange Protocol

Optimistic Fair Exchange protocol was designed for two parties to exchange in a fair way where an arbitrator always remains offline and will be referred only if any dispute happens. There are various optimistic fair exchange protocols with different security properties in the literature. Most of the optimistic fair exchange protocols satisfy resolution ambiguity where a signature signed by the signer is computational indistinguishable from the one resolved by the arbitrator. Huang et al. proposed the first generic framework for accountable optimistic fair exchange protocol in the random oracle model where it possesses resolution ambiguity and is able to reveal the actual signer when needed. Ganjavi et al. later proposed the first generic framework in the standard model. In this paper, we propose a new generic framework for accountable optimistic fair exchange protocol in the standard model using ordinary signature, convertible undeniable signature, and ring signature scheme as the underlying building blocks. We also provide an instantiation using our proposed generic framework to obtain an efficient pairing-based accountable optimistic fair exchange protocol with short signature.

Using Undeniable Signature on Elliptic Curves to Verify Servers in Outsourced Computations

Using Undeniable Signature on Elliptic Curves to Verify Servers in Outsourced Computations

Practical verifiably encrypted signatures based on discrete logarithms

AbstractBecause the discrete‐log‐based signature scheme on finite groups can be adapted to elliptic curves most efficiently, it has been developed widely in the mobile Internet. However, how to verifiably encrypt such signatures is a long‐lasting open problem. In this paper, we present the first verifiably encrypted discrete‐log signature scheme based on undeniable signatures, whose security depends on the discrete logarithm problem and the computational Diffie–Hellman problem in the random oracle model. Our security proof is under a strong security model against three types of inside adversaries with more powers. The proposed scheme can be deployed directly in the current Internet environment; nothing more than each party has an ElGamal key pair on a common finite group. Copyright © 2017 John Wiley & Sons, Ltd.

Undeniable signature scheme based over group ring

D. Chaum and H. van Antwerpen first introduced the concept of an undeniable signature scheme where the verification step is verified with the signer's co-operation. In this paper, first we discuss a combination of Discrete Logarithm Problem (DLP) and Conjugacy Search Problem (CSP) analysing its security. Then we propose an undeniable signature scheme in a non-abelian group over group ring whose security relies on difficulty of the combination of the DLP and the CSP. The complexity and security of our proposed scheme has also been discussed.

A new generic construction of anonymous designated confirmer signature for privacy-preserving fair exchange

ABSTRACTDesignated confirmer signature (DCS), introduced by Chaum at Eurocrypt 1994, can be used to control the public verifiability of a digital signature. It is a very useful tool in many applications which require a signature to remain anonymous and unverifiable until a certain time/condition is reached. In this paper, we propose a new generic construction of Anonymous Identity-Based DCS from Anonymous Identity-Based Signature. Interestingly, our construction also automatically implies an Anonymous Identity-Based Convertible Undeniable Signature scheme. We prove that the construction is secure for signer, verifier and confirmer in the standard model.

An Efficient Construction of Convertible Undeniable Proxy Signatures

In the undeniable signatures, the validity or invalidity can only be verified via the Confirmation/Disavowal protocol with the help of the signer. Convertible undeniable signatures provide the flexibility that a signer can convert an undeniable signatures into publicly verifiable one. A proxy signature scheme allows an entity to delegate his/her signing capability to another entity in such a way that the latter can sign messages on behalf of the former when the former is not available. Proxy signatures have found numerous practical applications in ubiquitous computing, distributed systems, mobile agent applications, etc. In this paper, we propose the first convertible undeniable proxy signature scheme with rigorously proven security. The properties Unforgeability, Invisibility and Soundness in the context of convertible undeniable proxy signatures are also clearly defined. The security of our construction is formally proven in the random oracle models, based on some natural complexity assumptions.

An efficient certificateless undeniable signature scheme

Certificateless cryptography addresses the private key escrow problem in identity-based systems, while overcoming the costly issues in traditional public key cryptography. Undeniable signature schemes were proposed with the aim of limiting the public verifiability of ordinary digital signatures. The first certificateless undeniable signature scheme was put forth by Duan. The proposed scheme can be considered as the certificateless version of the identity-based undeniable signature scheme which was introduced by Libert and Quisquater. In this paper, we propose a new scheme which is much more efficient comparing to Duan's scheme. Our scheme requires only one pairing evaluation for signature generation and provides more efficient confirmation and disavowal protocols for both the signer and the verifier. We also prove the security of our scheme in the strong security model based on the intractability of some well-known pairing-based assumptions in the random oracle model.

Secure Undeniable Threshold Proxy Signature Scheme

the threshold proxy signature scheme allows the original signer to delegate a signature authority to the proxy group to cooperatively sign message on behalf of an original signer. In this paper, we propose a new scheme which includes the features and benefits of the RSA scheme. Also, we will evaluate the security of undeniable threshold proxy signature scheme with known signers. We find that the existing threshold proxy scheme is insecure against the original signer forgery. In this paper, we show the cryptanalysis of an existed scheme. Additional, we propose the secure, undeniable and known signers threshold proxy signature scheme which answers the drawback of an existed scheme. We also demonstrate that a threshold proxy signature suffers from a conspiracy of an original signer and a secret share dealer, that the scheme is commonly forgeable, and cannot offer undeniable. We claim that the proposed scheme offers the undeniable characteristic.

Relation between Verifiable Random Functions and Convertible Undeniable Signatures, and New Constructions

Verifiable random functions (VRF) and selectively convertible undeniable signature (SCUS) schemes were proposed independently in the literature. In this paper, we observe that they are tightly related. This directly yields several deterministic SCUS schemes based on existing VRF constructions. In addition, we create a new probabilistic SCUS scheme, which is very compact. The confirmation and disavowal protocols of these SCUS are efficient, and can be run either sequentially, concurrently, or arbitrarily. These protocols are based on what we call zero-knowledge protocols for generalized DDH and non-DDH, which are of independent interest.

Secure Convertible Undeniable Signature Scheme Using Extended Euclidean Algorithm without Random Oracles

A convertible undeniable signature requires a verifier to interact with the signer to verify a signature and furthermore allows the signer to convert a valid one to publicly verifiable signature. In 2007, Yuen et al. proposed a convertible undeniable signature without random oracles in pairings. However, it is recently shown that Yuen et al.`s scheme is not invisible for the standard definition of invisibility. In this paper, we propose a new improvement by using extended Euclidean algorithm that can overcome the visibility attack. The proposed scheme has been evaluated based on computation and communication complexities and the performance comparisons of Yuen et al.`s scheme and various convertible undeniable signature schemes are provided. Moreover, it has been observed that the proposed algorithm reduces the computation and communication times significantly.

Short and efficient convertible undeniable signature schemes without random oracles

A convertible undeniable signature allows a signer to confirm or disavow a non-self-authenticating signature and also convert a valid one to a publicly verifiable signature. During the conversion, existing schemes either require the signer to be stateful, or have their security based on the random oracle assumption, or result in getting a large converter. In this work we propose a new construction, which supports both selective conversion and universal conversion, and is provably secure without random oracles. It has the shortest undeniable signature and the smallest converter. A signature consists of three bilinear group elements and just one group element each in a selective converter and a universal converter. The scheme can be extended further to support new features, such as the delegation of conversion and confirmation/disavowal, threshold conversion and others. We also propose an alternative generic construction of stateless convertible undeniable signature. Unlike the conventional ‘sign-then-encrypt’ paradigm, a signer in this new generic scheme encrypts a signature using identity-based encryption instead of public key encryption. It also enjoys the advantage of a short selective converter.

Short Convertible Undeniable Signature From Pairing

Undeniable signatures, introduced by Chaumand van Antwerpen, require a verifier to interact with thesigner to verify a signature, and hence allow the signerto control the verifiability of his signatures. Convertibleundeniable signatures allow the signer to convert undeniablesignatures into ordinary signatures. In this paperwe propose some extended variants of the famous Diffie-Hellman assumption on bilinear group system, then designa new convertible undeniable signature scheme and provideproofs for all relevant security properties based on the newassumption in the random oracle model. The advantages ofour scheme are the short length of the signatures, the lowcomputational cost of the signature, the receipt generationand the provable security.