Recover the Secret Components in a ForkCipher  

作　　者：HOU Tao ZHANG Jiyan CUI Ting 

机构地区：[1]PLA SSF Information Engineering University,Zhengzhou 450000,China

出　　处：《Chinese Journal of Electronics》2023年第3期597-602,共6页电子学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(61772547,61902428,61802438,61672031);the Foundation of Key Laboratory of National Defense Science and Technology(61421030107).

摘　　要：Recently, a new cryptographic primitive has been proposed called ForkCiphers. This paper aims at proposing new generic cryptanalysis against such constructions. We give a generic method to apply existing decompositions againt the underlying block cipher ε^(r) on the forking variant Forkε-(r-1)-r_(0)-(r+1-r_(0)). As application, we consider the security of ForkSPN and ForkFN with secret inner functions. We provide a generic attack against ForkSPN-2-r0-(4-r0) based on the decomposition of SASAS. And also we extend the decomposition of Biryukov et al. against Feistel networks in SAC 2015 to get all the unknown round functions in ForkFN-r-r0-r1for r ≤ 6 and r0+r1≤ 8. Therefore, compared with the original block cipher, the forking version requires more iteration rounds to resist the recovery attack.

关 键 词：Recovery attack ForkCipher Substitution-permutation network(SPN) Feistel network Secret design criteria 

分 类 号：TP309.7[自动化与计算机技术—计算机系统结构]