摘要
公钥加密方案的IND-CCA安全性通常要求其加密算法所使用的随机数是均匀随机独立选取的.但是,在区块链等分布式应用场景中,一个发送方通常要给多个接收方发送消息,如果给每个接收方的密文的生成过程都要重新选取相应随机数,将极大增加加密算法的计算量.针对这个问题,我们基于国密算法SM2提出了一个随机数可重用的多接收方公钥加密方案,并在随机预言机模型下证明该方案满足IND-CCA安全性.这一方案能够在区块链等多用户开放网络中保护数据的隐私性,其使用的随机数重用技术,在现实应用中能够有效减少发送方计算量,极大地提高加密算法效率.
It is commonly known that indistinguishability under chosen ciphertext attack(IND-CCA security)for public key encryption ordinarily requires that the random numbers,which are used during the encryption,are uniformly and independently sampled.However,in some distributed application scenarios(e.g.blockchain),a sender usually needs to send messages to multiple receivers.If the sender samples uniformly a random number for each encryption,the computational cost will be high.In order to solve this problem,this paper proposes a randomness re-using multi-recipient public-key encryption(RR-MRPKE)scheme based on SM2,and proves that it is IND-CCA secure(in the sense of MRPKE)in the random oracle model.The proposed scheme provides data privacy in open networks such as blockchain,and the employing technology of randomness re-using can effectively reduce the amount of computation and improve the encryption efficiency.
作者
赖俊祚
黄正安
翁健
吴永东
LAI Jun-Zuo;HUANG Zheng-An;WENG Jian;WU Yong-Dong(Jinan University,Guangzhou 510632,China;Peng Cheng Laboratory,Shenzhen 518055,China)
出处
《密码学报》
CSCD
2021年第4期699-709,共11页
Journal of Cryptologic Research
基金
国家自然科学基金(61922036,61702125,61802078)
广东省基础与应用基础研究重大项目(2019B030302008)。
关键词
区块链
多接收方公钥加密
随机数重用
blockchain
multi-recipient public-key encryption
randomness re-using
