几类多用户加密系统的选择打开攻击安全性关键问题研究

项目名称： 几类多用户加密系统的选择打开攻击安全性关键问题研究

项目编号： No.61472165

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 自动化技术、计算机技术

项目作者： 翁健

作者单位： 暨南大学

项目金额： 82万元

中文摘要： 选择密文攻击下的不可区分性（IND-CCA）已经成为公钥加密方案广为接受的安全概念。然而，近年研究结果表明IND-CCA安全的公钥加密方案并不一定能抵抗选择打开攻击，因而这类攻击引起了密码学界的高度关注。目前关于选择打开攻击的研究主要集中在传统公钥加密，而关于广播加密、基于身份广播加密和代理重加密这三类多用户密码系统的研究尚属空白。鉴于这一研究现状，本项目将针对这三类多用户密码系统的选择打开攻击安全性展开研究：(1)研究这三类密码系统的选择打开攻击安全定义，并探讨这些新定义与传统安全定义之间的关系；（2）研究选择打开选择密文安全广播加密和基于身份广播加密的通用构造方法；（3）设计选择打开选择密文安全广播加密的高效具体方案；（4）设计选择打开选择密文安全的代理重加密方案。本项目的研究成果将能丰富选择打开攻击领域的理论，并能增强广播加密、基于身份广播加密和代理重加密的安全性和实用性。

中文关键词： 公钥加密；选择打开攻击；广播加密；条件代理重加密；选择密文攻击

英文摘要： Indistinguishablility against chosen-ciphertext attacks (IND-CCA) has been widely accepted as the standard security notion for public-key encryption schemes. However, recent research results have indicated that IND-CCA secure public key encryption schemes may not resist selective opening attack, and hence this kind of attack attracts great interests in cryptography research fields. Existing research about selective opening attacks mainly focuses on traditional public key encryption, and pays no attention to some multi-user cryptosystems such as broadcast encryption, identity-based broadcast encryption and proxy re-encryption. In view of this, this project shall study on the selective opening security for the above three multi-user cryptosystems: (1) formalize the selective opening security notions for these three types of cryptosystems, and study the relationship between these security notions and traditional notions; (2) Study the generic methods for constructing chosen-ciphertext and selective opening secure broadcast encryption and identity-based broadcast encryption; (3) propose an efficient and concrete chosen-ciphertext and selective opening secure broadcast encryption scheme; (4) propose a chosen-ciphertext and selective opening secure proxy re-encryption scheme. The research fruits of this project can enrich the theory of selective opening attacks, and will also improve the security and applicability for broadcast encryption, identity-based broadcast encryption and proxy re-encryption.

英文关键词： public key encryption;selective opening attack;broadcast encryption;conditional proxy re-encryption;chosen-ciphertext attack