基于改进公证人机制的联盟链跨链隐私保护方案  

Cross-chain privacy protection scheme of consortium blockchain based on improved notary mechanism

作　　者：郭晓涵 姚中原 张勇 郭尚坤[1,2,3] 王超 斯雪明[1,3] GUO Xiaohan;YAO Zhongyuan;ZHANG Yong;GUO Shangkun;WANG Chao;SI Xueming(The Frontier Information Technology Research Institute,Zhongyuan University of Technology,Zhengzhou Henan 450007,China;Henan Key Laboratory of Network Cryptography Technology(Information Engineering University),Zhengzhou Henan 450001,China;Henan International Joint Laboratory of Blockchain and Data Sharing(Zhongyuan University of Technology),Zhengzhou Henan 450007,China)

机构地区：[1]中原工学院前沿信息技术研究院,郑州450007 [2]河南省网络密码技术重点实验室(信息工程大学),郑州450001 [3]河南省区块链与数据共享国际联合实验室(中原工学院),郑州450007

出　　处：《计算机应用》2023年第10期3028-3037,共10页journal of Computer Applications

基　　金：河南省重大公益专项(201300210300);河南省网络密码技术重点实验室研究课题(LNCT2021⁃A14);河南省科技攻关项目(222102210168)。

摘　　要：联盟链跨链交互既增强了联盟链应用的功能,又扩展了应用的使用范围,因此对促进联盟链应用推广和产业发展意义重大。然而,目前联盟链跨链交互依然存在着用户身份和资产交易信息隐私泄露的问题,进而阻碍了联盟链跨链交互技术的广泛应用。针对以上问题,提出一个基于改进公证人机制的联盟链资产跨链隐私保护方案。首先,在合约层引入哈希锁定机制来改进传统的单签名公证人跨链方式,从而降低传统公证人机制中心化作恶的风险;其次,利用同态加密的特性在保证交易合法的前提下,实现对交易资产的可用不可见;同时,利用多密钥生成中心(KGC)模式的标识密码算法实现在网络层上的用户身份隐私保护。理论分析和实验结果表明,所提方案对联盟链跨链交互时交易中的用户身份信息和资产信息具有良好的隐私保护效果,且相较于其他同类方案在签名和验证方面的开销更低。Cross-chain interaction of consortium blockchain not only enhances the function of the application of consortium blockchain,but also expands the scope of usage of the application,so that it is of great significance to the application promotion and industrial development of consortium blockchain.However,the cross-chain interaction of consortium blockchain still has the privacy disclosure problems of user identity and asset transaction information at present,which has become a major factor hindering the wide application of the cross-chain interaction technology of consortium blockchain.In view of the above problems,a cross-chain privacy protection scheme for consortium blockchain assets based on improved notary mechanism was proposed.In the scheme,a hash locking mechanism was introduced at the contract layer to improve the traditional single-signature notary cross-chain method at first,so as to reduce the risk of the traditional notary mechanism centralizing and doing evil.Then,the characteristics of homomorphic encryption were used to realize the usability and invisibility of transaction assets under the premise of ensuring the legitimacy of transactions.At the same time,the identity-based cryptographic algorithm of multi-Key Generation Center(KGC)mode was used to protect the user identity privacy at the network layer.The theoretical analysis and experimental results show that the proposed scheme has a good privacy protection effect on the user identity information and asset information in the cross-chain interaction of consortium blockchain,and this scheme has lower overhead in signature and verification than other similar schemes.

关 键 词：区块链 公证人 哈希锁定 同态加密 标识密码 隐私保护 

分 类 号：TP309[自动化与计算机技术—计算机系统结构] TP311.13[自动化与计算机技术—计算机科学与技术]