一种安全的云存储数据确定性删除方法

为解决云存储中的过期数据导致敏感信息泄漏的问题,提出了一种安全的数据确定性删除方法.该方法首先对文件F进行AON(All or Nothing)加密,将数据密文CF存储到云中,而将数据密文的存根C0与AON密钥参数一起进行广播加密,并将广播密文通过秘密共享算法分布式存储到DHT(Distributed Hash Table)网络中.DHT网络的动态更新将定期删除其中的广播密文,实现了AON密钥参数和存根C0的自动清除.在安全性方面,AON加密和广播加密使该方法能抵抗针对DHT网络中密钥信息的跳跃和嗅探攻击,以及针对数据密文CF的暴力攻击.

A Secure Data Assured Deletion Approach in Cloud Storage

To protect expired sensitive information from leaking in cloud storage,a secure data assured deletion approach was proposed. In the approach,the file F was firstly encrypted by AON( All or Nothing) algorithm. Then,the ciphertext CFwas stored into storage servers,while the ciphertext stub C0and key parameters of AON algorithm were broadcast encrypted. At last,the broadcast ciphertext was distributed into a DHT network by secret sharing algorithm.The broadcast ciphertext will be cleared periodically because of the periodical update of the DHT network. It implied that the AON key parameters and stub C0will be cleared automatically and the file F will be inaccessible after its lifetime.The approach could resist to hopping and sniffing attacks aiming at the key parameters in the DHT network and bruteforce attack aiming at the ciphertext CF,because of the adoption of AON and broadcast encryption algorithms.