一类具有安全加密功能的扩展MQ公钥密码体制  

Extended multivariate public key cryptosystems with secure encryption function

作　　者：王后珍[1,2] 张焕国[1,2] 王张宜[1,2] 唐明[1,2] 

机构地区：[1]武汉大学计算机学院空天信息安全与可信计算教育部重点实验室,武汉430072 [2]武汉大学软件工程国家重点实验室,武汉430072

出　　处：《中国科学：信息科学》2011年第11期1297-1309,共13页Scientia Sinica(Informationis)

基　　金：国家自然科学基金(批准号:60970115;60970116;61003267;61003268)资助项目

摘　　要：量子计算机的发展,对目前广泛应用的传统公钥密码体制(如RSA,ECC等)构成了严重的威胁.MQ公钥密码是目前抗量子计算密码领域中最为活跃的热点研究课题之一,但是目前MQ公钥密码只能用于签名,很难构造出安全的加密算法.同时,随着近年来多个MQ签名算法相继被攻破,人们对MQ类公钥密码体制的安全性产生了质疑.本文通过引入Hash认证技术、并结合传统MQ公钥密码算法,提出了一种扩展MQ公钥密码体制,它可看作是对传统MQ公钥密码算法结构的本质拓展.利用本文引入的Hash认证技术可有效地提升MQ签名算法的安全性,同时也可据此设计出安全高效的MQ公钥加密方法.Advances in quantum computers pose great threats on the currently used public key cryptographic algorithms such as RSA and ECC. As a promising candidate secure against attackers equipped with quantum computational power, multivariate public key cryptosystems （MPKCs） have attracted increasing attention in recently years. Unfortunately, the existing MPKCs can only be used as a multivariate signature scheme, and it remains unknown how to construct an efficient MPKC enabling secure encryption. Furthermore, some multivariate signature schemes have been shown insecure in recent years, and it is also not trivial to build MPKC which can serve as a secure signature scheme. By employing the basic MQ-trapdoors, this paper proposes a novel MPKC and shows how it can be used as a multivariate signature scheme and a multivariate encryption scheme, respectively. The goal is achieved by incorporating our new hash authentication techniques and some modification methods such as the Shamir＇s minus method. Thorough analysis shows that our schemes are secure and efficient. Our MPKC gives a positive response to the challenges in multivariate public key cryptography.

关 键 词：密码学 抗量子计算密码学 MQ问题 HASH函数 

分 类 号：TN918.1[电子电信—通信与信息系统]