对两个防欺诈秘密共享方案的安全性注记  

Security Notes on Two Cheat-Proof Secret Sharing Schemes

作　　者：王贵林[1] 卿斯汉[2] 

机构地区：[1]中国科学院软件研究所计算机重点实验室 [2]中国科学院软件研究所信息安全技术工程研究中心,北京100080

出　　处：《计算机研究与发展》2005年第11期1924-1927,共4页Journal of Computer Research and Development

基　　金：国家自然科学基金项目(60083007);国家"九七三"重点基础研究发展规划基金项目(G1999035802)~~

摘　　要：在(t,n)秘密共享体制中,秘密分配者将一个秘密信息分成n个秘密片断,然后让n个保存者每人保留一个片断·当需要恢复秘密信息时,任意t个秘密保存者拿出他们持有的秘密片断后,就可按既定的公开算法恢复出该秘密·在秘密恢复阶段,如何有效地鉴别每个秘密片断的真假是一个重要的研究问题·最近,费如纯等学者提出了两个基于RSA和单向函数的防欺诈秘密共享方案·但他们的方案实际上不具备防欺的功能,因为不良的秘密保存者可以非常容易地伪造假的、但能满足检验等式的秘密片断·由此导致的后果是,被欺骗的诚实保存者误以为恢复出的秘密信息是正确的·In （ t, n ） secret sharing schemes, a dealer splits a secret into n shares and sends a share to each of n participants. If necessary, any t share holders can provide their secret shares together and then recover the secret by using a publicly specified algorithm. In the secret recover phase of such schemes, how to detect the cheating from share holders is an important technical issue. Based on RSA cryptosystem and oneway function, Fei, et al. recently proposed two cheat-proof secret sharing schemes. However, it is shown that in fact their schemes do not provide the function of cheat-proof. The reason is that malicious share holders can easily forge false shares such that the authenticating equality is satisfied. The result is that honest participants will be cheated and misled to believe that the recovered secret is correct.

关 键 词：秘密共享 密码学 信息安全 

分 类 号：TP393[自动化与计算机技术—计算机应用技术]