TRE加密技术研究  

Research on Timed-Release Encryption

作　　者：袁科[1] 刘哲理[1] 贾春福[1] 马昊玉 吕述望[2] 

机构地区：[1]南开大学计算机与控制工程学院,天津300071 [2]信息安全国家重点实验室(中国科学院信息工程研究所),北京100093

出　　处：《计算机研究与发展》2014年第6期1206-1220,共15页Journal of Computer Research and Development

基　　金：国家"九七三"重点基础研究发展计划基金项目(2013CB834204);国家自然科学基金项目(60973141;61272423;61300241);高等学校博士学科点专项科研基金项目(20100031110030;20120031120036);天津市自然科学基金项目(13JCQNJC00300;14JCYBJC15300)

摘　　要：TRE(timed-release encryption)是一种由发送者指定未来特定解密时间的密码原语,其所具备的时间相关特性在许多具有时间敏感性的现实应用场景(如电子投标、分期付款、在线考试、电子机密档案)均有着十分重要的应用价值.首先,在对已有TRE方案进行分类并分析总结各类TRE特点的基础上,给出TRE的形式化定义与安全目标定义;其次,介绍了3种TRE基本架构及其所涉及的数学问题,并给出了3种典型的TRE构造方案;再次,分析总结了TRE的安全目标及其在自适应选择明文与自适应选择密文攻击模型下的安全性;然后,开展了TRE的应用研究,特别是提出TRE与其他密码机制结合的前提条件和一般化方案,并构造出一个TRE结合可搜索加密的具体方案;最后,讨论了TRE未来需进一步研究的问题.TRE （timed-release encryption） is a cryptographic primitive where the sender encrypts a message to prevent from being decrypted by anyone,including the designated receiver,Until a future pre-set release time specified by the sender.Some other extensions make TRE have time properties of decrypting in advance and decrypting in a time interval.Since many applications in practice are timesensitive,such as sealed-bid auctions,mortgage payments,on-line examinations and electronic confidential archives,TRE is considered as a valuable cryptographic tool.By summarizing existing TRE schemes and analyzing their characteristics,we give the formal definition and security goals definition of TRE.On the top of that,we introduce three fundamental frameworks of TRE along with their related mathematical problems,and further describe some typical constructions.We comprehensively analyze the security goals （specifically the message confidentiality and message unforgeability） of TRE,as well as their security bound under the adaptive chosen-plaintext attack and adaptive chosen-ciphertext attack models.Finally,we conduct research on the application of TRE; especially propose the preconditions and generic schemes for combining TRE with other cryptographic mechanisms.And we also construct a concrete scheme of public key timed-release searchable encryption which is a combination of TRE and public key encryption with keyword search.The future research directions in TRE are discussed in addition.

关 键 词：Timed-Release加密 时间服务器 时间陷门 双线性映射 可证明安全 随机预言机 

分 类 号：TP309.07[自动化与计算机技术—计算机系统结构]