International Association for Cryptologic Research

International Association
for Cryptologic Research

IACR News item: 21 April 2014

Lin Ding, Chenhui Jin, Jie Guan, Chuanda Qi
ePrint Report ePrint Report
By combining the time-memory-data tradeoff (TMDTO) attack independently proposed by Babbage and Goli\\\'{c} (BG) with the BSW sampling technique, this paper explores to mount a new TMDTO attack on stream ciphers. The new attack gives a wider variety of trade-offs, compared with original BG-TMDTO attack. It is efficient when multiple data is allowed for the attacker from the same key with different IVs, even though the internal state size is twice the key size. We apply the new attack to MICKEY and Grain stream ciphers, and improves the existing TMDTO attacks on them. Our attacks on Grain v1 and Grain-128 stream ciphers are rather attractive in the respect that the online time, offline time and memory complexities are all better than an exhaustive key search, and the amount of keystream needed are completely valid. Finally, we generalize the new attack to a Guess and Determine-TMDTO attack on stream ciphers, and mount a Guess and Determine-TMDTO attack on SOSEMANUK stream cipher with the online time and offline time complexities both equal to $2^{128}$, which achieves the best time complexity level compared with all existing attacks on SOSEMANUK so far.

Expand

Additional news items may be found on the IACR news page.