Open AccessMeet‐in‐the‐middle attacks on round‐reduced tweakable block cipher Deoxys‐BC
Author(s) -
Li Rongjia,
Jin Chenhui
Publication year - 2019
Publication title -
iet information security
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.308
H-Index - 34
eISSN - 1751-8717
pISSN - 1751-8709
DOI - 10.1049/iet-ifs.2018.5091
Subject(s) - block cipher , construct (python library) , man in the middle attack , computer science , computer security , cipher , key (lock) , arithmetic , cryptography , mathematics , computer network , encryption
Deoxys‐BC is a tweakable block cipher designed by Jean et al . at ASIACRYPT 2014 within the TWEAKEY framework. Then Deoxys‐BC is used in the CAESAR finalist Deoxys. In this study, the authors consider the security of Deoxys‐BC against meet‐in‐the‐middle attack in the single‐key setting. Using the idea that a chosen tweak difference allows to cancel a difference in the state, they can construct 5‐round meet‐in‐the‐middle distinguisher on Deoxys‐BC‐128‐128 which can be extended to attack on 8‐round Deoxys‐BC‐128‐128. Moreover, they construct 6‐round meet‐in‐the‐middle distinguisher on Deoxys‐BC‐256‐128 which can be extended to attack on 10‐round Deoxys‐BC‐256‐128. As far as the authors know, these are the best attacks against Deoxys‐BC in the single‐key setting.