Secure Threshold Ring Signature Based on SM9

Nowadays, it becomes a major issue that has become increasingly prominent to ensure the privacy and security of information. With the wide application of SM9 algorithm in various fields, it is particularly important to improve the security of SM9 algorithm. Therefore, many researchers use the SM9 algorithm for supporting the underlying cryptography. And group signature, ring signature and two-party signature are introduced in succession to design the related scheme with significant effecting. In order to further improve the signature security and promote the promotion of SM9 algorithm. First, the SM9 identification and cipher algorithm is improved by using multi-KGC(Key Generation Center) to generate system parameters to achieve the purpose of improving the security of the key in this paper. Second, a threshold ring signature scheme based on SM9 is proposed by combining SM9 with threshold ring signature. The analysis shows that, compared with the existing schemes, the proposed scheme has more advantages in security, such as higher anonymity, unforgeability and non-repudiation, while resisting malicious user attacks and malicious KGC attacks. This scheme extends SM9 from single user signature to multi-users signature, and increases the application scenarios of SM9, which plays a positive role in the promotion of SM9.