近年来, 已有多种SM2数字签名算法的两方门限计算方案被提出, 这些方案能够有效地增强SM2数字签名算法的私钥安全性. 根据不同的密钥拆分方法, 已有公开方案可以分为两类, 分别基于乘法和加法拆分. 再根据不同的签名随机数构造方法, 衍生出多种两方门限计算方案. 提出SM2数字签名算法的两方门限计算方案框架, 所提框架给出安全的两方门限计算基本过程, 又可以引入不同构造的签名随机数. 利用提出的框架, 结合随机数的不同构造, 完成所提框架的多种实例化, 即得到SM2数字签名算法多种不同的两方门限计算方案. 所提框架的实例化, 包括现有已知的23种两方门限计算方案, 也包括多种新的方案.
There are a lot of two-party threshold schemes for SM2 digital signatures proposed in recent years, which can significantly enhance the security of private keys for SM2 digital signatures. According to different methods of key splitting, public schemes can be divided into two types: multiplicative key splitting and additive key splitting. Further, these public schemes can be subdivided into various two-party threshold schemes according to different constructions of the signature random number. This study proposes the framework of two-party threshold schemes for SM2 digital signature, which provides a safe basic calculation process of two-party threshold schemes and introduces the signature random number that can be constructed variously. With the proposed framework and various constructions of the random number, this study achieves the instantiation of the framework, obtaining a variety of two-party threshold schemes for SM2 digital signature. The instantiation includes 23 known two-party threshold schemes, as well as a variety of new schemes.