【摘要】 提出并描述了一种扩展的密文策略属性基加密(ECP-ABE)机制.对CP-ABE树形访问策略结构进行扩展,使其能够支持not和比较运算符表达式运算操作,显著增强了CP-ABE机制的访问控制能力.最后证明了所设计的ECP-ABE机制在标准模型下是适应性选择明文攻击(CPA)安全的,扩展的访问结构树不会给加密系统带来额外的安全问题.更多还原

【Abstract】 An extended ciphertext-policy attribute based encryption(ECP-ABE) scheme was proposed which extends tree access structure to support access policy formulas involving not and comparing operators,and significantly enhanced access control capabiity of CP-ABE scheme.ECP-ABE improves the access control ability of CP-ABE obviously and is proven to be chosen plaintext(CPA) secure under the decisional Bilinear Diffie-Hellman(DBDH) assumption in the standard model.Extended access tree structure does not bring extra security to the encyption system.更多还原