Rapid realization of truncated differential attack on 6-round DES
LIU Wei
HE Yongzhong
ZHAO Jia
LI Lin
Abstract：In the process of the truncated differential attack to block cipher,some substitution-boxes(S-boxes) will have a great deal of cipher candidate values,which will use a lot of time when the remaining key is attacked by violence.This paper mainly analyzes the reasons and the related probability of the emergence of multi sets of recommended values,and then puts forward two improvement schemes to reduce the number of the candidate key and improve the efficiency of the attack.The first method uses the incomplete dependence among round keys,and makes full use of the identical key that is in the first and in the final round.But the probability of one set of candidate value is about 40 ％.The second method uses the whole 6 bits candidate key in 8 S-boxes,and obtains the final key by counting the numbers of values.Using this method can reduce the number of 48 bits candidate to 1 with the probability close to one.Through the 6-round DES attack experimental results,the second method can recover the initial key with the probability close to one.
Keywords：differential cryptanalysisdata encryption standardtruncated differentialS-boxesblock cipher
Publication Date：2017-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：8( 28-35 )