A Post-quantum Certificateless Ring Signature Scheme for Privacy-Preserving of Blockchain Sharing Economy

TLDR: Wang et al. as mentioned in this paper proposed a post-quantum certificateless ring signature algorithm over lattice, which can hide the signer identity information and resist quantum computing attacks and effectively avoid certificate management problem and third-party central key escrow problem.

Abstract: Classical cryptography is no longer secure under quantum computing background. In traditional sharing economy, the centralized management mode leads to data tampering and privacy leakage problems. Targeting at these problems, in our paper, a novel privacy protection scheme is designed for sharing economy based on blockchain. Firstly, we propose a post-quantum certificateless ring signature algorithm over lattice, which can hide the signer’s identity information and resist quantum computing attacks. Moreover, our proposed scheme can effectively avoid certificate management problem and third-party central key escrow problem. Secondly, we use the principle of bimodal Gaussian rejection sampling to generate signature. It can reduce the sampling times in signature phase and greatly improves the signature efficiency. Notably, the signature distribution is independent of signer’s private key, which can better avoid the disclosure of signer’s private key information. Thirdly, we construct a blockchain sharing economy transaction scheme based on the proposed signature algorithm that can protect the privacy of user. Finally, security and efficiency of our scheme are analyzed that have lower storage cost and time cost than other related schemes under the random oracle model.