Certificateless Proxy Signature Scheme Research Articles

Provably Secure Certificateless Proxy Signature Scheme in the Standard Model

<p>Proxy signature frees the original signer from the heavy signature work. Many certificateless proxy signature (CLPS) schemes have been proposed in the last ten years. The security proofs of most known schemes are given in the random oracle model (ROM). There are only two CLPS schemes with provably security in the standard model (SM). However, in which the size of the system parameter increase linearly with the size of the user’s identity information. That increase the storage burden of the key generation center. In this paper, a new CLPS scheme is constructed and the security proofs are showed in SM. The size of system parameters and the master key are constant in the scheme. Requiring only three pairing operations, the new scheme is more efficient and suitable for mobile computing.</p> <p> </p>

Security Analysis of the First Certificateless Proxy Signature Scheme Against Malicious-But-Passive KGC Attacks

AbstractRecently, Yang et al. proposed the first certificateless proxy signature scheme against malicious-but-passive key generation center (MKGC) attacks. They proved that their scheme can resist the MKGC attacks in the standard model. In this paper, we point out that their scheme cannot achieve this security because the adversary can forge valid signatures.

A Provably Secure Certificateless Proxy Signature Scheme Against Malicious-But-Passive KGC Attacks

AbstractIn certificateless proxy signature (CLPS), the key generation center is responsible for initializing the system parameters and can obtain the opportunity to adaptively set some trapdoors in them when wanting to launch some attacks. Until now, how to withstand the malicious-but-passive key generation center (MKGC) attacks in CLPS is still an interesting problem. In this paper, we focus on the challenging issue and introduce a CLPS scheme provably secure in the standard model. To the best of our knowledge, we are the first to demonstrate its security under MKGC attacks by adopting the technology of embedding the classic difficulty problems into the target entity public key rather than the system parameters during the security proof process.

Provably secure certificateless proxy signature scheme in the standard model

Certificateless public key cryptography was introduced to solve the key escrow problem in identity-based cryptography and eliminate the use of certificates. As an extension of proxy signature in the certificateless setting, certificateless proxy signature has attracted much attention and many schemes have been proposed recently. So far, only one certificateless proxy signature scheme without using the random oracles was found in the literature. Unfortunately, cryptanalysis shows that it suffers from some security drawbacks and fails in achieving the existential unforgeability. To overcome the security weaknesses in this scheme, we newly propose a certificateless proxy signature scheme without random oracles. In the standard model, we strictly prove it to be existentially unforgeable against chosen message attacks. Compared with previous certificateless proxy signature scheme without random oracles, the new scheme offers stronger security while enjoying better performance.

Efficient Certificateless Proxy Signature Scheme

A proxy signature scheme allows a proxy signer to sign messages on behalf of an original signer within a given context. We propose a certificateless proxy signature (CLPS) scheme, and prove it's security under a stronger security model. Although some good results were achieved in speeding up the computation of pairing function in recent years, it is still interesting to design cryptosystem with less pairing operations. Taken into account the computational costs, our scheme only requires 2 pairing operations in delegation and signing, respectively.

Applied-Information Technology in Certificateless Proxy Signature Scheme without Bilinear Pairings

This paper researches on the existing certificateless proxy signature scheme, there is almost no certificateless proxy signature scheme based on discrete logarithm up till now. Combining the knowledge of discrete logarithm over finite field and the advantages of certificateless cryptography, this paper proposes an efficient certificateless proxy signature scheme based on the discrete logarithm without bilinear pairings. To avoid the key escrow problem in the id-based cryptosystem and the saving certificate problem in the traditional public cryptography, meet the good properties of the proxy signature, such as unforgery, dependence of the proxy keys, distinguish of the proxy signature and anti-abuse. The scheme does not use the bilinear pairings, and based on the hard problem of discrete logarithm in the finite field, given the proof and discussion of the validity and security of the scheme.

Certificateless Proxy Signature from RSA

Although some good results were achieved in speeding up the computation of pairing function in recent years, it is still interesting to design efficient cryptosystems with less bilinear pairing operation. A proxy signature scheme allows a proxy signer to sign messages on behalf of an original signer within a given context. We propose a certificateless proxy signature (CLPS) scheme from RSA and prove its security under the strongest security model where the Type I/II adversary is a super Type I/II adversary.

Provably Secure Forward Secure Certificateless Proxy Signature Scheme

In order to deal with key exposure problem, we introduce forward secure technique into certificateless proxy signature scheme, and propose the formal definition and security model of the forward secure certificateless proxy signature. Our security model takes into account the super adversary in certificateless signature. Furthermore, we present a construction of forward secure certificateless proxy signature scheme with bilinear maps. Based on the difficulty of computational Diffie-Hellman problem, we prove the scheme is secure against chosen message attack in the random oracle model. Finally, we analyze efficiency of the proposed scheme.

An efficient certificateless proxy signature scheme without pairing

The proxy signature scheme allows a proxy signer to sign messages on behalf of an original signer, a company or an organization. Such schemes have lots of practical applications, particularly in distributed computing, where delegation of rights is quite common. Recently, the certificateless public key cryptography has attracted much attention since it could solve the certificate management problem in the traditional public cryptography and the key escrow problem in the identity-based cryptography. Many certificateless proxy signature schemes using pairing have been proposed. The pairing operation is a very complicated operation. So the performance of these schemes is not very good. In this paper, we propose the first certificateless proxy signature scheme without pairing. We argue that due to significant reduction in costs of computation and storage, our scheme is particularly suitable for practical applications with severely constrained resources. We also show our scheme is secure against both of the super Type I and the super Type II adversaries.

On the Security of a Certificateless Proxy Signature Scheme with Message Recovery

A proxy signature scheme allows a proxy signer to sign messages on behalf of an original signer within a given context. It has lots of practical applications in distributed systems, grid computing, mobile agent applications, distributed shared object systems, global distribution networks, and mobile communications. Recently, Padhye et al. proposed a certificateless proxy signature scheme with message recovery and claimed the scheme is secure against both of the two types of adversaries. However, in this paper, we will show that Padhye et al.’s scheme is not secure against the Type I adversary. The analysis shows their scheme is not secure for practical applications.

ECDLP‐based certificateless proxy signature scheme with message recovery

AbstractCertificateless public key cryptography (PKC) eliminates the use of certificates in traditional PKC and the key escrow problem in identity‐based PKC. Up to now, a number of certificateless proxy signature (CLPS) schemes have been proposed. However, only a little attention has been paid to the construction of CLPS schemes with message recovery. Recently, Singh and Verma proposed a CLPS scheme with message recovery from bilinear pairings. Total computation cost of a pairing is higher than that of elliptic curve‐based scalar multiplication over elliptic curve group. So, schemes without pairings would be more appealing in terms of efficiency. To the best of our knowledge, there is no provable secure CLPS scheme with message recovery based on elliptic curve discrete log problem. We first propose such CLPS scheme. Our scheme is secure against existential forgery under adaptive chosen message and ID attacks. Furthermore, it is more efficient than Singh and Verma's scheme for practical applications. Copyright © 2012 John Wiley & Sons, Ltd.

Efficient certificateless proxy signature scheme with provable security

In this paper we propose a very efficient and provably secure proxy signature scheme with implicit certificate (called “ certificateless proxy signature scheme”), where a receiver does not have to verify a certificate before verifying a signed message, yet only the original signer or the proxy signer who properly registered its public key and identity information is able to sign. Unlike traditional approaches which assume a PKI where the original signer and the proxy signer already hold their public keys and digital certificates, our scheme does not need for each user to have a public key and a certificate, thus we can save the time for verifying the original signer’s and the proxy signer’s certificates in the proxy signature verification phase. Furthermore, we present a formal security model for our scheme under the intractability of the computational Diffie–Hellman problem in the random oracle model.

Delegation of signing rights using certificateless proxy signatures

A proxy signature scheme allows a proxy signer to sign messages on behalf of an original signer within a given context. It has lots of practical applications in distributed systems, grid computing, mobile agent applications, distributed shared object systems, global distribution networks, and mobile communications. In the last years, fruitful achievements have been seen in certificateless public key cryptography which has the advantages of no certificate management and no key escrow compared with traditional public key cryptography and identity-based public key cryptography respectively. However, the existing certificateless proxy signature schemes is either insecure or without formal security analysis. In this paper, we formalize the security model of certificateless proxy signature schemes and propose a provably secure certificateless proxy signature scheme with formal security proof under the computational Diffie–Hellman assumption.

Security analysis of certificateless proxy signature scheme

Certificateless cryptography eliminates the need of certificates in the Public Key Infrastructure (PKI) and solves the inherent key escrow problem. Recently,Fan Rui et al. proposed a certificateless proxy signature scheme based on a certificateless signature scheme. They claimed that their scheme satisfied the security requirements of certificateless proxy signature schemes. However,the analysis of their scheme showed that it was insecure against the two kinds of attacks in certificateless cryptosystems,i.e. public key replacement attacks and malicious Key Generating Centre (KGC) attacks. The attack methods and the defensive measures were presented.

Cryptanalysis and improvement of certificateless proxy signature scheme

The certificateless proxy signature scheme proposed by Fan Rui etc.was analyzed and their scheme turned out to be insecure.Furthermore,a serious security flaw was discovered in the proxy key generation algorithm,because the private key of the original signer could be recovered by the proxy signer.Unfortunately,the same security flaw was also found out in other proxy signature schemes.Finally,a comprehensive and improved scheme was proposed,whose security was based on the Computational Diffie-Hellman Problem(CDHP).

Certificateless Proxy Signature Scheme with Provable Security

This paper studies proxy signatures in the newly proposed certificateless public key setting. The authors present a very strong security model for certificateless proxy signature schemes against both Super Type I Adversary and Super Type II Adversary. And also an efficient construction of certificateless proxy signature scheme using bilinear maps is put forward. The security of this scheme is based on the infeasibility of the Computational Diffie-Hellman problem and is formally proven under the security model of certificateless proxy signature schemes. Due to its security, high efficiency and freedom from certificate management, it may have practical applications in electronic commerce and mobile agent systems, etc.

On constructing certificateless proxy signature from certificateless signature

In proxy signature schemes, an original signer A delegates its signing capability to a proxy signer B, in such a way that B can sign message on behalf of A. The recipient of the final message verifies at the same time that B computes the signature and that A has delegated its signing capability to B. Recently many identity-based (ID-based) proxy signature schemes have been proposed, however, the problem of key escrow is inherent in this setting. Certificateless cryptography can overcome the key escrow problem. In this paper, we present a general security model for certificateless proxy signature scheme. Then, we give a method to construct a secure certificateless proxy scheme from a secure certificateless signature scheme, and prove that the security of the construction can be reduced to the security of the original certificateless signature scheme.

Certificateless signature and proxy signature schemes from bilinear pairings

Due to avoiding the inherent escrow of identity-based cryptography and yet not requiring certificates to guarantee the authenticity of public keys, certificateless public key cryptography has received a significant attention. Due to various applications of bilinear pairings in cryptography, numerous pairing-based encryption schemes, signature schemes, and other cryptographic primitives have been proposed. In this paper, a new certificateless signature scheme based on bilinear pairings is presented. The signing algorithm of the proposed scheme is very simple and does not require any pairing computation. Combining our signature scheme with certificateless public key cryptography yields a complete solution of certificateless public key system. As an application of the proposed signature scheme, a certificateless proxy signature scheme is also presented. We analyze both schemes from security point of view.