Identity-Based Integrity Auditing Scheme With Sensitive Information Hiding for Proxy-Server-Assisted Cloud Storage Applications

In recent years, the model of storing personal local data on cloud servers to save local space has become popular. However, this model also has certain security risk: the data stored in the cloud may be accidentally damaged or lost. How to perform remote integrity audit of these data is a meaningful research problem. Many current auditing schemes rely on the encryption of the entire data file to ensure data’s privacy, and the tag-generation of data owner (DO) itself, which bring a significant computational burden to the DO. In this article, we propose a technique of only blinding sensitive locations of user data without encrypting the entire file to improve the computational efficiency of current cloud auditing schemes. At the same time, it is also proposed to delegate the generation process of authentication tags to a proxy server (PS) to save DO’s computing resource. Then the integrity audit process is based on stored data file as well as PS’s authentication tags. In addition, the access control strategy of data user (DU)-request-then-DO-authorization has been implemented to facilitate the sharing of stored data, where DU means data user. Finally, security and performance analyses were conducted on the proposed system. The results indicate that our system is provably secure under classical cryptographic assumption and has certain performance advantages compared with related works.