具有隐私保护的固定密文长度分布式属性基加密方案

摘要

User privacy,communication costs,and computational costs are the main factors affecting the security and efficiency of attribute-based encryption schemes for multiple-authorized organizations.However, some existing multi-authority organization attribute-based encryption schemes for protecting user privacy either protect the privacy of the user's global identifiers and attributes or hide the access structure in the ciphertext.Some existing multi-authoring institution attribute-based encryption schemes for protecting user privacy either protect the privacy of the user's global identifiers and attributes or hide the access structure in the ciphertext.However, it failed to combine the two to jointly achieve the protection of user privacy.Therefore,the article implemented protection of user privacy from the above two aspects,and proposed a fixed ciphertext length distributed attribute-based encryption scheme with a privacy protection function.In addition,the program also fully considered the user's computational cost and storage cost,ensuring that the ciphertext length was fixed.The scheme which is based on the decision-making DBDH difficult problem in the selection of security model is proved to choose the plaintext attack security.%用户隐私、通信代价和计算代价是影响多授权机构属性基加密方案安全性和效率的主要因素.但是,已有的一些保护用户隐私的多授权机构属性基加密方案要么是保护了用户的全局标识符和属性的隐私,要么是隐藏了密文中的访问结构,未能将二者结合起来共同实现对用户隐私的保护.因此,将从以上两个方面实现对用户隐私的保护,并提出一个具有隐私保护功能的固定密文长度分布式属性基加密方案.此外,该方案还充分考虑了用户的计算代价以及存储代价,确保了密文长度固定.方案基于判定性DBDH困难问题在选择安全模型中被证明是选择明文攻击安全的.