基于身份体制下多密文等值测试加密方案的一般性构造

General Construction of Identity-based Encryption with Multi-ciphertext Equality Test

基于身份的多密文等值测试加密方案(IB-MET)具有广泛的应用前景,但目前仍缺少高效的构造方案.本文研究基于身份体制下的多密文等值测试加密方案构造.将传统公钥体制构造的加密算法抽象成数据封装和系数封装两个具体的步骤.提出将数据封装机制进行变形后再结合系数封装机制即可实现相应体制下具有多密文等值测试功能的加密方案.给出了基于身份体制多密文等值测试加密方案的一般性构造,以Beneh-Franklin IBE为例给出了一个具体的构造实例.方案基于一个基于身份加密(IBE)方案和BDH困难假设,相比传统的多密文等值测试加密方案,主要增加的计算开销为传统加密算法到基于身份加密算法的额外开销.

Identity-based encryption with multiple ciphertext equality test(IB-MET)schemes can be applied in various applications.However,there still lacks a systematic research on how to generally achieve an efficient construction.This paper studies the construction of IB-MET schemes.First,traditional public-key encryption with multiple ciphertext equality tests are treated as two basic mechanisms,namely the data encapsulation and coefficient encapsulation.Second,a general construction of encryption schemes with multiple ciphertext equality test is proposed by combining the coefficient encapsulation mechanism and the data encapsulation mechanism in the corresponding public-key cryptographic setting.Then,a general construction of IB-MET schemes is presented,the Beneh-Franklin IBE is used as an example to illustrate how to achieve a concrete IB-MET scheme.The proposed general construction requires an identity-based encryption(IBE)scheme and the BDH assumption.Compared with the schemes in the traditional public-key setting,the additional computational costs in the general construction is mainly introduced from the difference between IBE and public-key encryption schemes.