可验证的密文策略属性基加密安全外包方案  

Secure and Verifiable Outsourced Ciphertext Policy Attribute-based Encryption

作　　者：闫玺玺[1] 何广辉 于金霞[1] YAN Xi-Xi;HE Guang-Hui;YU Jin-Xia(College of Computer Science and Technology,Henan Polytechnic University,Jiaozuo 454000,China)

机构地区：[1]河南理工大学计算机科学与技术学院,焦作454000

出　　处：《密码学报》2020年第5期628-642,共15页Journal of Cryptologic Research

基　　金：“十三五”国家密码发展基金(MMJJ20170122);国家自然科学基金(61802117);河南省科技攻关项目(192102210280);河南省高等学校青年骨干教师(2018GGJS058);河南省高等学校重点科研项目(20A413005)。

摘　　要：本文针对属性基加密方案的外包过程,提出一种可验证的密文策略属性基加密安全外包方案.方案首先对前人所提的模幂安全外包算法进行改进,分别优化多个底数和单个底数模幂安全外包算法,将两个算法的正确性验证概率全部提升为"1".其次,采用改进的模幂安全外包算法,通过数学分割与盲化的方式,将密文组件中的底数与指数进行处理隐藏后外包给云服务器进行计算,一方面防止云服务器获取明文相关信息,另一方面数据加密者和使用者只需要进行常数个指数运算,工作量大大减轻.再者,方案在随机预言机模型下被证明满足选择性抗重放选择密文攻击安全.最后通过与其它相关方案在功能与效率两方面进行对比分析,表明本文方案对于资源受限移动设备在外包环境下是有效的.In most attribute-based encryption schemes,exponential operation and bilinear pairing operation are the most basic operations,The cost of encryption is often linearly related to the number of attributes in the access control policy.The decryption overhead is often linearly dependent on the number of user attribute sets,so most of the decryption and encryption operations are outsourced to the cloud computing service in order to reduce the workload of the data owner and the data user.In this paper,a secure and verifiable outsourced ciphertext policy attribute based encryption scheme is proposed.The scheme improves outsource-secure algorithm for modular exponentiation,and optimizes multiple base and single base modulus power outsourcing algorithms respectively.The probability of correctness verification of modular exponentiation outsource-secure algorithms on multiple-base and single-base can reach"1".Moreover,using the improved outsource-secure algorithm for modular exponentiation,the base and exponent in the ciphertext component are hidden and sent to the cloud server by the mathematical segmentation and blinding method.Therefore,the cloud computing platform cannot obtain the plaintext information,and the workload of data owner and user is reduced to a constant number of exponential operations.At last,the scheme is proved to be secure in selective replayable chosen ciphertext attack under the random oracle model.The comparison with other related schemes in terms of function and efficiency shows that the proposed scheme is feasible and superior under the outsourced environment,especially for the resource-constrained mobile terminals.

关 键 词：属性基加密 外包计算 可验证性 

分 类 号：TP309.7[自动化与计算机技术—计算机系统结构]