云存储中基于联合属性的密文策略加密方案

Cipher-policy encryption scheme based on union attributes in cloud environment

为解决云存储环境下基于属性的密文策略变更问题,提出基于联合属性的密文策略加密方案。通过结合简单的基于属性的密文策略方案,引入联合属性,转换普通访问结构树,实现云存储环境下访问策略的动态变更。理论分析结果表明,该方案可有效减少策略属性变更时数据属主的计算开销,随着策略属性的不断增加,有效减少了整体计算开销,具有较高安全性、可靠性和实用性。

For the problem of the ciphertext policy change in cloud storage environment, a cryptographic access control solution based on attribute-based encryption （ABE） was proposed. The eiphertext policy based on attribute-based encryption （CP-ABE） was combined, the union attributes were introduced, the common access structure tree was converted, and the dynamic change of access policy was realized in cloud storage environment. Theoretical analysis shows that the proposed scheme can effectively re- duce computational costs when the policy changes. With the increasing of the policy attributes, the proposed scheme can reduce the overall computational costs, and it has better security, reliability and practicability.