基于匿名广播加密的云存储访问控制方法

摘要

针对现有的匿名广播加密方法在加解密性能和安全性方面的不足,提出一种基于拉格朗日插值多项式的匿名广播加密方法.首先定义了可以抵御自适应敌手攻击的匿名广播加密安全模型;然后在合数阶双线性群环境下采用拉格朗日插值多项式对方案进行了构建,在保证用户身份匿名性的同时,实现了高效的加解密;最后基于子群判定假设和合数阶判定双线性Diffie-Hellman假设,在标准模型下证明了方法针对自适应敌手具有密文的机密性和接收者匿名性.实验与性能分析表明,方法具有较低的通信和计算开销,可以有效地解决云存储中密文数据的匿名访问控制问题.%Focusing on the deficiencies on performance and security of the existing anonymous broadcast encryption scheme,a new anonymous broadcast encryption scheme based on the Lagrange interpolation polynomial was proposed.Firstly,an anonymous broadcast encryption security model against adaptive adversaries was defined.Then the scheme was constructed based on the Lagrange interpolation polynomial under the composite order bilinear group settings,which ensures user identity anonymity and achieves an efficient encryption and decryption at the same time.Finally,based on the subgroup decision assumption and the composite decisional bilinear Diffie-Hellman assumption,the security was proved in standard model,which shows that the proposed scheme has both ciphertext confidentiality and receiver anonymity against adaptive adversaries.Experimental results and performance analysis show that the proposed method has low communication and computing overhead,and can efficiently solve the anonymous access control issues of ciphertext data in cloud storage.