云存储中隐私保护的线性同态加密方案

Linear Homomorphic Encryption Scheme for Privacy Protection of Cloud storage

云存储数据具有访问方便、可靠性高及可测量等优势,然而也存在一些安全风险,如敏感数据泄露、未授权访问及数据完整性等。针对敏感数据泄露问题,本文提出了一基于整多项式环上差错学习(R-LWE)问题的有效线性同态加密方案(LHES),该方案可对要上传云端的数据进行加密并以密文形式分布式存储,其安全性是基于R-LWE问题的困难性。分析表明,该方案在效率上较基于LWE的加法同态加密方案有很大改进,并且在标准模型下是选择明文攻击安全的。最后,给出了本文方案在云存储隐私保护中的应用架构。

Cloud storage possesses enormous advantages：ubiquitous access,high reliability and scalability and so on.But,unfortunately,also several security risks such as sensitive data disclosure,unauthorized access and data integrity etc are still existing.Aiming at the problem of sensitive data disclosure,an efficient linear homomorphic encryption scheme from R-LWE is proposed in this paper.In this scheme,the data is encrypted first and then stored in cloud in a distributed manner,and its security is based on the difficulty of R-LWE problem.The analyses indicate that the efficiency of the proposed scheme is much more efficient than the additive homomorphic encryption scheme from LWE,and it is secure under chosen plaintext attacks （CPA） in standard model.Finally,the architecture of privacy protection of cloud storage based on the proposed scheme is introduced in this paper.