Certificateless Linkable Ring Signature Scheme Based on SM2 Algorithm

Ring signatures are advanced cryptographic tools that authenticate messages while protecting the signer's identity, playing a crucial role in user privacy. However, traditional ring signatures allow a signer to generate multiple unique signatures for the same message, which verifiers cannot distinguish. Linkable ring signatures address this by enabling verifiers to determine if multiple signatures come from the same signer while preserving anonymity. Certificateless public key cryptosystems eliminate the need for managing public key certificates and key escrow, enhancing key management security. This paper presents a CLRS scheme based on the SM2 algorithm, combining the benefits of linkable and certificateless signatures. It resolves certificate management and key escrow issues while safeguarding user privacy and preventing signature misuse. Notably, existing CLRS schemes often depend on bilinear pairings and modular exponentiation, which can compromise computational efficiency. Our proposed scheme avoids bilinear pairings, significantly improving efficiency, making it particularly suitable for applications in electronic voting and digital currencies.