1 Provable Ownership of Encrypted Files in De-duplication Cloud Storage Chao Yangy z, Jianfeng May and Jian Renz ySchool of CS, Xidian University Xi’an, Shaanxi, 710071. Email: fchaoyang,
[email protected] zDepartment of ECE, Michigan State University East Lansing, MI 48824. Email: fchaoyang,
[email protected] Abstract—The rapid adoption of cloud storage services has tells a client that it does not have to upload the file, it created an issue that many duplicated copies of files are stored in means that some other clients have the same file, which the remote storage servers, which not only wastes the communica- could be a sensitive information [5]. More seriously, Halevi tion bandwidth for duplicated file uploading, but also increases the cost of security data management. To solve this problem, et al. recently found some new attacks to the client-side client-side deduplication was introduced to avoid the client from deduplication system [6]. In these attacks, by learning just uploading files already existed in the remote servers. However, the a small piece of information about the file, namely its hash existing scheme was recently found to be vulnerable to security value, an attacker is able to get the entire file from the server. attacks in that by learning a small piece of information related These attacks are not just theoretical. Some similar attacks to the file, such as the hash value of the file, the attacker may be able to get full access of the entire file; and the confidentiality that were implemented against Dropbox were also discovered of the date may be vulnerable to “honest-but-curious” attacks.