New Related-Tweakey Boomerang Attacks and Distinguishers on Deoxys-BC  

作　　者：Jiamei LIU Lin TAN Hong XU 

机构地区：[1]PLA Strategic Support Force Information Engineering University,Zhengzhou 450001,China

出　　处：《Chinese Journal of Electronics》2024年第3期683-693,共11页电子学报（英文版）

基　　金：supported by the National Cryptography Development Fund of China (Grant Nos.MMJJ20170103 and MMJJ20180204)。

摘　　要：Deoxys-BC is the primitive tweakable block cipher of the Deoxys family of authenticated encryption schemes.Based on existing related-tweakey boomerang distinguishers,this paper improves the boomerang attacks on 11-round Deoxys-BC-256 and 13-round Deoxys-BC-384 by the optimized key guessing and the precomputation technique.It transfers a part of subtweakey guess in the key-recovery phase to the precomputation resulting in a significant reduction of the overall time complexity.For 11-round Deoxys-BC-256,we give a related-tweakey boomerang attack with time/data/memory complexities of 2^(218.6)/2^(125.7)/2^(125.7),and give another attack with the less time complexity of 2^(215.8)and memory complexity of 2120 when the adversary has access to the full codebook.For 13-round Deoxys-BC-384,we give a related-tweakey boomerang attack with time/dat a/memory complexities of 2^(k-96)+2^(157.5)/2^(120.4)/2^(113).For the key size k=256,it reduces the time complexity by a factor of 2^(31)compared with the previous 13-round boomerang attack.In addition,we present two new related-tweakey boomerang distinguishers on 11-round Deoxys-BC-384 with the same probability as the best previous distinguisher.

关 键 词：Block cipher Tweakable block cipher Boomerang attack Related-tweakey 

分 类 号：TN918.1[电子电信—通信与信息系统]