School of Science, Xi'an University of Technology, Xi'an, Shaanxi, China.
School of Computer Science and Engineering, Xi'an University of Technology, Xi'an, Shaanxi, China.
PLoS One. 2018 May 24;13(5):e0197318. doi: 10.1371/journal.pone.0197318. eCollection 2018.
Ciphertext-policy attribute-based encryption (CP-ABE) scheme is a new type of data encryption primitive, which is very suitable for data cloud storage for its fine-grained access control. Keyword-based searchable encryption scheme enables users to quickly find interesting data stored in the cloud server without revealing any information of the searched keywords. In this work, we provide a keyword searchable attribute-based encryption scheme with attribute update for cloud storage, which is a combination of attribute-based encryption scheme and keyword searchable encryption scheme. The new scheme supports the user's attribute update, especially in our new scheme when a user's attribute need to be updated, only the user's secret key related with the attribute need to be updated, while other user's secret key and the ciphertexts related with this attribute need not to be updated with the help of the cloud server. In addition, we outsource the operation with high computation cost to cloud server to reduce the user's computational burden. Moreover, our scheme is proven to be semantic security against chosen ciphertext-policy and chosen plaintext attack in the general bilinear group model. And our scheme is also proven to be semantic security against chosen keyword attack under bilinear Diffie-Hellman (BDH) assumption.
密文策略属性基加密（CP-ABE）方案是一种新型的数据加密原语，由于其具有细粒度的访问控制，非常适合数据云存储。基于关键字的可搜索加密方案使用户能够在不透露搜索关键字任何信息的情况下，快速找到存储在云服务器中的感兴趣的数据。在这项工作中，我们为云存储提供了一种具有属性更新功能的基于关键字的可搜索属性基加密方案，它是属性基加密方案和基于关键字的可搜索加密方案的结合。新方案支持用户的属性更新，特别是在我们的新方案中，当用户的属性需要更新时，只需要更新与该属性相关的用户密钥，而不需要更新其他用户的密钥和与该属性相关的密文，这得益于云服务器的帮助。此外，我们将具有高计算成本的操作外包给云服务器，以减轻用户的计算负担。此外，我们的方案在一般双线性群模型中被证明是针对选择密文策略和选择明文攻击的语义安全的。并且我们的方案在双线性 Diffie-Hellman（BDH）假设下也被证明是针对选择关键字攻击的语义安全的。
