文献类型：期刊文献

中文题名：利用区块链构建公平的安全多方计算

英文题名：Constructing fair secure multi-party computation based on blockchain

作者：黄建华[1];江亚慧[1];李忠诚[1]

机构：[1]华东理工大学信息科学与工程学院,上海200237

年份：2020

卷号：37

期号：1

起止页码：225

中文期刊名：计算机应用研究

外文期刊名：Application Research of Computers

收录：CSTPCD;;北大核心:【北大核心2017】；CSCD:【CSCD_E2019_2020】；

基金：国家自然科学基金面上项目(61472139).

语种：中文

中文关键词：安全多方计算;区块链;智能合约;公平性

外文关键词：secure multi-party computation(MPC);blockchain;smart contracts;fairness

摘要：针对安全多方计算(MPC)中大部分参与者不诚实情况下无法获得公平性这一问题,基于区块链智能合约构造惩罚机制,提出了公平的安全MPC协议。协议分为两个阶段,分别为基于可验证秘密共享的MPC阶段和公平的秘密重建阶段,参与方只要收集t+1个正确份额即可得到最终输出。协议利用同态承诺来验证秘密份额的正确性,使用超时机制来判别恶意参与方的提前终止行为,并对恶意方进行经济惩罚。安全性分析表明诚实参与方能够获得最终输出,否则将得到经济补偿;性能分析表明参与方只需缴纳一轮押金并且大量复杂的秘密份额验证工作都在链下,协议的执行效率得到保证。
This paper proposed a fair secure multi-party computation(MPC)protocol to solve the problem that fairness cannot be achieved when there is no honest majority.The protocol constructed a penalty mechanism based on smart contracts which were stored on the blockchain.It included the MPC phase based on verifiable secret sharing and the fair secret reconstruction phase.The participants could obtain the final output by collecting just t+1 correct shares.The protocol utilized homomorphic commitments to verify the correctness of the secret shares,employed timeouts to identify the premature abort behaviors of malicious parties,and punished the aborting parties financially.Security analysis shows that honest participants can get the final output,otherwise they will get financial compensation.Performance analysis shows that the protocol requires only one coin-transfer round and a large number of complex secret share verification work is off the chain,which ensures the implementation efficiency.