Lattice-Based Verifiably Encrypted Signature Scheme without Gaussian Sampling for Privacy Protection in Blockchain

Abstract

Before the transaction data in the blockchain is successfully linked, its signature must be publicly verified by a large number of nodes in the blockchain, which is also one of the ways to leak transaction information. To alleviate the contradiction between the public verifiability of signatures and the protection of transaction privacy, we introduce a verifiably encrypted signature scheme into the blockchain. A verifiably encrypted signature scheme contains two parts of signature information: the encrypted signature is used for public verification, and the ordinary signature is used for internal verification. To reach this goal even better, we design a new lattice-based verifiably encrypted signature scheme, which separates the parameter settings of the signer and the adjudicator, and replaces the Gaussian sampling algorithm with a small range of uniform random sampling, achieving better efficiency and security.