Biclique Cryptanalysis of TWINE

Abstract

TWINE is a lightweight block cipher firstly proposed at ECRYPT Workshop on Lightweight Cryptography 2011 and then presented at the Conference on Selected Areas in Cryptography 2012. The cipher consists of 36 rounds and has two versions TWINE-80 and TWINE-128 supporting key lengths of 80 and 128 bits, respectively. The block length of the two versions is 64-bit. In this paper, we present the first single-key attacks on both the versions of the cipher. In these attacks, we use the recently developed biclique technique. The complexities of the attacks on TWINE-80 and TWINE-128 are 279.10 and 2126.82 respectively and the data requirement for the two attacks is 260.