FBC模型的伪随机性和超伪随机性  

Pseudorandomness and Super-pseudorandomness of FBC Model

作　　者：刘楠[1] 金晨辉 于俊伟[2] 崔霆[1] LIU Nan;JIN Chen-Hui;YU Jun-Wei;CUI Ting(PLA SSF Information Engineering University,Zhengzhou 450001,China;School of Artificial Intelligence and Big Data,Henan University of Technology,Zhengzhou 450001,China)

机构地区：[1]战略支援部队信息工程大学,河南郑州450001 [2]河南工业大学人工智能与大数据学院,河南郑州450001

出　　处：《软件学报》2024年第10期4826-4836,共11页Journal of Software

基　　金：河南省优秀青年科学基金(222300420100);国家自然科学基金(61772547)。

摘　　要：FBC分组密码算法是入选2018年全国密码算法设计大赛第2轮的10个分组密码算法之一.FBC主要采用四分支两路Feistel结构设计,是一个实现效率高的轻量级分组密码算法.将FBC算法抽象为FBC模型,并研究该模型的伪随机性和超伪随机性,在FBC轮函数都是相互独立的随机函数的条件下,给出能够与随机置换不可区分所需的最少轮数.结论表明,在选择明文攻击条件下,4轮FBC与随机置换不可区分,因而具有伪随机性;在自适应性选择明密文攻击条件下,5轮FBC与随机置换不可区分,因而具有超伪随机性.As one of the ten block cipher algorithms selected for the second round of the 2018 National Cryptographic Algorithm Design Contest,Feistel-based block cipher(FBC)is an efficient and lightweight block cipher algorithm with a four-branch and two-fold Feistel structure.In this study,the FBC algorithm is abstracted as the FBC model,and the pseudorandomness and super-pseudorandomness of the model are studied.It is assumed that the FBC round functions are independent random functions,and a method to find the minimal number of FBC rounds is provided,which will keep FBC indistinguishable from a random permutation.Finally,the study comes to the conclusion that under the chosen-plaintext attack,four rounds of FBC are indistinguishable from random permutation,so the model has pseudorandomness;under the adaptive chosen-plaintext and ciphertext attack,five rounds of FBC are indistinguishable from random permutation,so the model has super-pseudorandomness.

关 键 词：分组密码 FBC模型 伪随机性 超伪随机性 

分 类 号：TP309[自动化与计算机技术—计算机系统结构]