Research on the Format-Preserving Encryption Techniques

Abstract

围绕基本构建方法、加密模型和安全性等方面,对保留格式加密(format-preserving encryption,简称FPE)的研究现状进行了综述.在基本构建方法方面,介绍了Prefix,Cycle-Walking 和Generalized-Feistel 方法的工作原理及适用范围;在加密模型方面,分析了FPE 模型或方案所呈现的构造特点,介绍了典型模型的工作原理,总结了Feistel网络的类型及其在FPE 中的应用情况;在安全性方面,描述了保留格式加密的安全目标及相关的游戏模型,分析了各安全目标之间的关系.最后介绍了保留格式加密的应用领域,指出性能、完整性认证以及FPE 在数据库加密应用中如何对密文进行范围查询、算术运算将是进一步需要解决的问题.这些研究工作将对保留格式加密的研究起到一定的促进作用.;The paper reviews the current research situation of FPE (format-preserving encryption) including basic constructing methods, encryption modes and security. When describing the basic constructing methods, it introduces the basic principles of Prefix, Cycle-Walking and Generalized-Feistel and their application scopes. When explaining the encryption modes, it mainly analyzes the construction features of FPE modes or schemes, introduces the principles of three classical modes, summarizes the different types of Feistel networks and presents an overview of their applications in FPE. When talking about the security, it describes the security notions of FPE and their corresponding games, analyzing the relationship among them. In the end, it introduces the application scopes of FPE and points out that performance, integrity authentication and key problems of database encryption with FPE, such as making range query and arithmetic operation on encrypted data, are the major problems to be solved in the future. All these works will play a role in promoting research of format-preserving encryption.