Automatic search for differential characteristics in ARX ciphers

A Survey of ARX-based Symmetric-key Primitives

“…Aaraj et al used MILP techniques to search for differential trail for two rounds of ChaCha at bit-level, and six rounds at word level [33]. In [42], Saho et al proposed the algorithm to search for differential cryptanalysis applied on ChaCha stream cipher. However, the search algorithm also has some defects that need to be improved and optimised.…”

“…Chen et al [47] later improved the impossible cryptanalysis of 17-round TEA and 23-round XTEA based on 14 rounds and 13 rounds of impossible differential, respectively. In 2014, Biryukov and Velichkov [42] proposed the first differential full trail with 18-round TEA block cipher. Hong et al 2003 found full trail for 14-round XTEA with probability of 60.76 2 [28].…”