On the Effect of the Key-Expansion Algorithm in Simon-like Ciphers
Jinyu Lu, Yunwen Liu, Tomer Ashur, Chao Li · The Computer Journal · 2021
Abstract In this work, we investigate how the choice of the key-expansion algorithm and its interaction with the round function affect the resistance of Simon-like ciphers against rotational-XOR cryptanalysis. We observe that, among the key-expansion algorithms we consider, Simon is most resistant, while Simeck is much less so. Implications on lightweight ciphers design are discussed and open questions are proposed.