Security issues in cloud computing have become a hot topic in academia and industry, and CP-ABE is an effective solution for managing and protecting data. When data is shared in cloud computing, they usually have multiple access structures that have hierarchical relationships. However, existing CP-ABE algorithms do not consider such relationships and just require data owners to generate multiple ciphertexts to meet the hierarchical access requirement, which would incur substantial computation overheads. To achieve fine-grained access control of multiple hierarchical files effectively, first we propose an efficient hierarchical CP-ABE algorithm whose access structure is linear secret sharing scheme. Moreover, we construct an attribute-based hierarchical access control scheme, namely AHAC. In our scheme, when a data visitor’s attributes match a part of the access control structure, he can decrypt the data that associate with this part. The experiments show that AHAC has good security and high performance. Furthermore, when the quantity of encrypted data files increases, the superiority of AHAC will be more significant.

云计算中的安全性问题已成为学术界和行业中的热门话题，CP-ABE是管理和保护数据的有效解决方案。在云计算中共享数据时，它们通常具有具有分层关系的多个访问结构。但是，现有的CP-ABE算法不考虑这种关系，仅要求数据所有者生成多个密文以满足分层访问要求，这将招致大量计算开销。为了有效地实现对多个分层文件的细粒度访问控制，首先我们提出了一种高效的分层CP-ABE算法，其访问结构为线性秘密共享方案。此外，我们构造了一个基于属性的分层访问控制方案，即AHAC。在我们的方案中 当数据访问者的属性与访问控制结构的一部分匹配时，他可以解密与此部分关联的数据。实验表明，AHAC具有良好的安全性和高性能。此外，当加密数据文件的数量增加时，AHAC的优势将更加显着。