Efficient and Provably-secure Certificateless Strong Designated Verifier Signature Scheme without Pairings

Strong designated verifier signature (generally abbreviated to SDVS) allows signers to obtain absolute control over who can verify the signature, while only the designated verifier other than anyone else can verify the validity of a SDVS without being able to transfer the conviction. Certificateless PKC has unique advantages comparing with certificate-based cryptosystems and identity-based PKC, without suffering from key escrow. Motivated by these attractive features, we propose a novel efficient CL-SDVS scheme without bilinear pairings or map-to-point hash operations. The proposed scheme achieves all the required security properties including EUF-CMA, non-transferability, strongness and non-delegatability. We also estimate the computational and communication efficiency. The comparison shows that our scheme outperforms all the previous CL-(S)DVS schemes. Furthermore, the crucial security properties of the CL-SDVS scheme are formally proved based on the intractability of SCDH and ECDL assumptions in random oracle model

A Novel Strong Designated Verifier Signature Scheme without Random Oracles

In this study, a novel pairing based strong designated verifier signature scheme based on non-interactive zero knowledge proofs is proposed. The security of the proposal is presented by sequences of games without random oracles; furthermore, this scheme has a security proof for the property of privacy of the signer’s identity in comparison with the scheme proposed by Zhang et al. in 2007. In addition, this proposal compared to the scheme presented by Huang et al. in 2011 supports non-delegatability. The non-delegatability of our proposal is achieved since we do not use the common secret key shared between the signer and the designated verifier in our construction. Furthermore, if a signer delegates her signing capability which is derived from her secret key on a specific message to a third party, then, the third party cannot generate a valid designated verifier signature due to the relaxed special soundness of the non-interactive zero knowledge proof. To the best of our knowledge, this construction is the first attempt to generate a designated verifier signature scheme with non-delegatability in the standard model, while satisfying of non-delegatability property is loose

Attack on Kang et al.\u27s Identity-Based Strong Designated Verifier Signature Scheme

In this paper, we present a universal forgery attack on Kang et al.\u27s identity-based strong designated verifier signature (IBSDVS) scheme. We show anyone can forge a valid IBSDVS on an arbitrary message without the knowledge of the private key of either the signer or the designated verifier. Moreover, we point out that Kang et al.\u27s scheme does not satisfy the properties of strongness and non-delegatability. At last, an improved IBSDVS scheme for Kang et al.\u27s scheme is presented, and it is provably secure and achieves all the requirements for an IBSDVS

Non-delegatable Identity-based Designated Verifier Signature

Designated verifier signature is a cryptographic primitive which allows a signer to convince a designated verifier of the validity of a statement but in the meanwhile prevents the verifier from transferring this conviction to any third party. In this work we present the \emph{first} identity-based designated verifier signature scheme that supports non-delegatability, and prove its security in the random oracle model, based on computational Diffie-Hellman assumption. Our scheme is perfectly non-transferable, and its non-delegatability follows the original definition proposed by Lipmaa et al. \cite{LipmaaWaBa05}

A Pairing Based Strong Designated Verifier Signature Scheme without Random Oracles

In this study, a novel strong designated verifier signature scheme based on bilinear pairings with provable security in the standard model is proposed, while the existing ones are secure in the random oracle model. In 2007 and 2011, two strong designated verifier signature schemes in the standard model are proposed by Huang et al. and Zhang et al., respectively; in the former, the property of privacy of the signer’s identity is not proved and the security of the latter is based on the security of a pseudorandom function. Our proposal can deal with the aforementioned drawbacks of the previous schemes. Furthermore, it satisfies non-delegatability for signature verificatio

On Delegatability of Some Strong Designated Verifier Signature Schemes

A strong designated verifier signature scheme makes it possible for a signer to convince a designated verifier that she has signed a message in such a way that the designated verifier cannot transfer the signature to a third party, and no third party can even verify the validity of a designated verifier signature. In 2005, Lipmaa, Wang, and Bao identified a new essential security property, non delegatability, of designated verifier signature schemes. Briefly, in a non delegatability designated verifier signature scheme, neither a signer nor a designated verifier can delegate the signing rights to any third party without revealing their secret keys. However, this paper shows that four recently proposed strong designated verifier signature schemes are delegatable. These schemes do not satisfy non delegatability secure requirement of strong designated verifier signature schemes

On the Security of a Certificateless Strong Designated Verifier Signature Scheme

Recently, Chen et al. proposed the first non-delegatable certificateless strong designated verifier signature scheme and claimed that their scheme achieves all security requirements. However, in this paper, we disprove their claim and present a concrete attack which shows that their proposed scheme is forgeable. More precisely, we show that there exist adversaries who are able to forge any signer\u27s signature for any designated verifier on any message of his choice

A non-delegatable identity-based strong designated verifier signature scheme

In a strong designated verifier signature scheme, no third party can verify the validity of a signature. On the other hand, non-delegatability, proposed by Lipmaa, Wang and Bao, is another stronger notion for designated verifier signature schemes. In this paper, we formalize a security model for non-delegatable identity based strong designated verifier signature (IDSDVS) schemes. Then a novel non-delegatable IDSDVS scheme based on pairing is presented. The presented scheme is proved to be non-delegatable, non-transferable and unforgeable under the Gap Bilinear Diffie-Hellman assumption

Identity Based Strong Designated Verifier Signature Scheme

Identity based cryptosystem simplifies the key management and revocation problem. Here we propose an Identity Based Strong Designated Verifier Signature (IBSDVS) scheme using bilinear pairings. The Designated Verifier Signature scheme described in [10] is identity based but it suffers from the deligatability as pointed out in [4]. We analyse the security of the scheme and show that the problem of delegatability does not exist in our scheme