可追责和完全可验证外包解密CP-ABE方案  

Traceable and fully verifiable for outsourced decryption for CP-ABE

作　　者：李聪 杨晓元[1,2] 白平[1,2] 王绪安 LI Gong1,2. YANG Xiaoyuan1,2, BAI Ping1,2, WANG Xu＇an1,2(1. College of Cryptographic Engineering, Engineering College of Armed Police Force, Xi＇an Shaanxi 710086, China; 2. Key Laboratory of Network and Information Security of the Chinese Armed Police Force, Xi＇an Shaanxi 710086, Chin)

机构地区：[1]武警工程大学密码工程学院,西安710086 [2]网络与信息安全武警部队重点实验室,西安710086

出　　处：《计算机应用》2018年第8期2249-2255,共7页journal of Computer Applications

基　　金：国家自然科学基金资助项目(U1636114;61772550)~~

摘　　要：在密文策略属性加密方案(CP-ABE)中,解密密钥定义在多个用户共享的属性上,任何私钥无法追溯到原有密钥的所有者,恶意用户可能为了经济利益泄露他们的解密权限给第三方,并且不会被发现。另外,大多数现有CPABE方案的解密成本和密文大小随访问结构的复杂程度呈线性增长。上述问题严重限制了CP-ABE的应用。为此,通过定义追责列表来追溯故意泄露密钥的用户,通过外包运算降低解密运算成本,提出一个可追责和完全可验证外包解密的CP-ABE方案。该方案可以同时检查授权用户和非授权用户转换密文结果的正确性,而且支持任意单调访问结构,可追责性不会给其他安全性带来任何影响。最后在标准模型中证明了该方案是选择明文攻击(CPA)安全的。In Ciphertext-Policy Attribute-Based Encryption（ CP-ABE） schemes,the private key is defined on attributes shared by multiple users. For any private key that can not be traced back to the owner of the original key,the malicious users may sell their decryption privileges to the third parties for economic benefit and will not be discoverable. In addition,most of the existing ABE schemes have a linear increase in decryption cost and ciphertext size with the complexity of access structure.These problems severely limit the applications of CP-ABE. By defining a traceable table to trace the users who intentionally disclosed the key,the cost of the decryption operation was reduced through the outsourcing operation,and a CP-ABE scheme with traceable and fully verifiable outsourced decryption was proposed. The scheme can simultaneously check the correctness for transformed ciphertexts of authorized users and unauthorized users,and supports any monotonous access structure,which traceability will not have any impact on its security. Finally,the proposed scheme is proved to be CPA（ Chosen Plaintext Attack）-secure in the standard model.

关 键 词：属性基加密 完全可验证性 外包解密 可追责 双线性映射 多线性映射 选择明文攻击安全 

分 类 号：TP309.7[自动化与计算机技术—计算机系统结构]