基于同态加密的区块链交易数据隐私保护方案  

A Privacy-preserved Scheme for Blockchain Transaction Based on Homomorphic Encryption

作　　者：肖瑶 冯勇 李英娜 付晓东 XIAO Yao;FENG Yong;LI Ying-Na;FU Xiao-Dong(Yunnan Key Laboratory of Computer Technology Applications,Kunming University of Science and Technology,Kunming 650504,China)

机构地区：[1]昆明理工大学云南省计算机技术应用重点实验室,昆明650504

出　　处：《密码学报》2022年第6期1053-1066,共14页Journal of Cryptologic Research

基　　金：国家自然科学基金(62062047,61962030);云南省区块链应用技术重点实验室(YNB202111)。

摘　　要：区块链技术因其去中心化、去信任、防篡改等特性而被广泛认为是一种很有前景的应用方案.然而分布式系统的高度自主性,使得使用受信任的加密技术来确保公开网络环境中用户的隐私和信息安全显得尤为重要.本文提出基于同态加密算法的交易数据隐私保护方案,在不依赖可信第三方的情况下,为用户在区块链交易中提供完整且可靠的隐私保护机制.为了克服区块链交易费用较高和确认时间过长带来的不可扩展问题,使用基于支付渠道网络的支付方案在支持快速和频繁的交易的同时赋予链下交易的账户余额以及交易金额完整的隐私保护机制.在交易安全和隐私保护需求背景下对该方案进行了安全性分析和性能评估,结果表明该方案在利用区块链保护基础交易的同时实现了交易数据的完整机密性.Blockchain technology is widely accepted as a promising solution because of many good characteristics such as decentralization,trustlessness,and tamper-proofing.However,due to the high autonomy of distributed systems,it is important to use trusted encryption technique to ensure the privacy and information security of users in the open network environment.In this paper,a privacy protection scheme of blockchain transactions based on HE(homomorphic encryption)is presented,with a view to provide a reliable privacy protection mechanism for the transaction of users in the blockchain,without relying on trusted third parties.Moreover,in order to overcome non-scalability induced by high transaction cost and long confirmation time of blockchain,the payment scheme based on PCN(payment channel network)is adopted to support fast and frequent transactions while providing complete privacy protection mechanism for the account balance and transaction amount of the off-chain transactions.Based on the background of transaction security and privacy protection requirements,the security and the feasibility are analyzed.The results show that,while using blockchain to protect the basic transactions,the proposed scheme achieves transaction data confidentiality.

关 键 词：区块链 同态加密算法 支付渠道网络 隐私保护方案 

分 类 号：TP309.7[自动化与计算机技术—计算机系统结构]