基于密文策略属性基加密算法的云存储数据更新方法  

Data updating method for cloud storage based on ciphertext-policy attribute-based encryption

作　　者：刘荣 潘洪志 刘波 祖婷 方群[1,2] 何昕 王杨[1,2] 

机构地区：[1]安徽师范大学数学计算机科学学院,安徽芜湖241002 [2]安徽师范大学网络与信息安全安徽省重点实验室,安徽芜湖241002

出　　处：《计算机应用》2018年第2期348-351,442,共5页journal of Computer Applications

基　　金：安徽省自然科学基金资助项目(1708085MF156);安徽省重大人文社科基金资助项目(SK2014ZD033)~~

摘　　要：针对云计算数据易遭非法窃取和恶意篡改问题,提出一种支持动态更新操作的密文策略的属性基加密方案(DU-CPABE)。首先利用线性分割思想将数据分成固定大小的数据块,然后采用密文策略属性基加密(CP-ABE)算法对各数据块进行加密,最后提出一种Address-Merkle Hash Tree(A-MHT)搜索树结构,借助A-MHT快速定位数据块实现云服务器中数据动态更新。经理论分析验证了方案的安全性,而且在理想信道中的仿真实验结果显示,在更新次数为5时,此方案相比CP-ABE方案的数据更新时间开销平均下降幅度为14.6%。实验结果表明:DU-CPABE方案在云计算服务中数据动态更新这一过程能够有效地减小数据更新的时间开销,同时降低系统开销。Cloud computing data are vulnerable to be theft illegally and tampered maliciously. To solve these problems, a Dynamic Updating Ciphertext-Policy Attribute-Based Encryption( DU-CPABE) scheme which enables both data dynamic updating and security protection was proposed. Firstly, by using linear partitioning algorithm, data information was divided into fixed size blocks. Secondly, the data blocks were encrypted by using Ciphertext-Policy Attribute-Based Encryption( CPABE) algorithm. Finally, based on conventional Merkle Hash Tree( MHT), an Address-MHT( A-MHT) was proposed for the operation of dynamically updating data in cloud computing. The theoretical analysis proved the security of the scheme, and the simulation in ideal channel showed that, for five updates, compared with CP-ABE method, the average time overhead of data update was decreased by 14. 6%. The experimental results show that the dynamic updating of DU-CPABE scheme in cloud computng services can effectively reduce data update time and system overhead.

关 键 词：云计算 数据动态更新 密文策略属性基加密算法 Merkle哈希树 云安全 

分 类 号：TP309.2[自动化与计算机技术—计算机系统结构]