一种可抵抗关键词猜测攻击的动态非对称可搜索加密方案

密文搜索可以用于保护用户存储在云端的文件，防止隐私的泄露，允许用户在不泄露明文信息的情况下进行搜索，根据使用密钥体制的不同，可分为对称可搜索加密和非对称可搜索加密。但是现有大多数的PEKS方案的索引构造都是基于文件-关键词对，每次搜索都需要遍历所有文件，这会使方案的搜索效率较为低下，并且现有的PEKS方案大都只支持静态的搜索操作，云端的文件不能进行动态更新必然带来资源上的浪费和使用上的不便。针对存在的问题，提出一种较为高效的动态公钥可搜索加密方案，与其他同类方案相比具有一定的优势，并在随机预言模型下证明该方案具有适应性动态选择关键词攻击下的安全性，且可抵抗敌手的关键词猜测攻击。

A Dynamic Public Key Searchable Encryption Scheme Against Keyword Guessing Attack

Ciphertext search can be used to protect user’s privacy when searching in plaintext. However, the index struction of most existing PEKS schemes are based on file keyword pairs, and each search needs to traverse all files, which will make the search efficiency of the scheme low. Moreover, the existing PEKS schemes only support static search operations, and the files in the cloud can not be updated dynamically, which will inevitably lead to waste of resources and inconvenience in using. In view of the existing problems, this paper proposes a more efficient dynamic public key searchable encryption scheme, which has certain performance advantages compared with other schemes, and proves that the scheme has the security under the adaptive dynamic keyword selection attack under the random oracle model, and can resist the keywords guessing attack.