Abstract: Recent years, how to protect user privacy data on the blockchain reasonably and efficiently is a key issue in the current blockchain technology field. Based on this, in this paper, a secure multi-party computation protocol is designed based on the Pedersen commitment and Schnorr protocol (protocol of blockchain based on Pedersen commitment linked schnorr protocol for multi-party computation, BPLSM). Through constructing the structure of the protocol and carrying out formal proof calculations, it is confirmed that the protocol can be integrated into the blockchain network to merge different private messages for efficient signing under anonymity. In addition, by analyzing the nature and security of the protocol, it can be proved that the overhead about computation of the general-purpose privacy computing scheme using the BPLSM protocol on the blockchain is low, and it also has strong information imperceptibility. In the end, experimental simulation results show that the time cost of BPLSM protocol verification in a small-scale multi-party transaction with a fixed number of people is about 83.5% lower than that of the current mainstream BLS signature.

Key words: blockchain, privacy computing, secure multi-party computation, Pedersen commitment, Schnorr signature, BLS signature