固定密文长度的可验证属性基外包解密方案

摘要

传统密钥策略属性基加解密方案存在密文长度随着属性增加而线性增加,在通信过程中消耗用户大量的通信带宽的缺点.提出了属性加密的改进方案,基于密钥策略属性加密,提出具有固定密文长度的可验证外包解密方案,在非单调访问结构实现密文长度固定,有效节省通信带宽,通过对外包密钥生成算法的改进,实现一次模指数运算,有效缩短外包密钥生成时间.通过运用哈希函数,实现外包解密的验证性,并对其安全性进行了证明.%The traditional key policy attribute base encryption and decryption scheme has the disadvantages that the ciphertext length increases linearly with the increase of the number of attributes,and consumes a large amount of communication bandwidth of the user in the communication process.The improved scheme of attribute encryption was proposed.Based on the encryption of key policy attributes,a verifiable packet decryption scheme with fixed ciphertext length was proposed.In the non-monotonic access structure,the cipher length was fixed,and the communication bandwidth was effectively saved.Through the improvement of outsourced key generation algorithm,a primary modular exponentiation operation was realized,and the generation time of key generation was effectively shortened.The hash function was used to realize the verification of the decryption and its security was proved.