NUSH

For other uses, see NUS High School of Math and Science.

In cryptography, NUSH is a block cipher invented by Anatoly Lebedev and Alexey Volchkov for the Russian company LAN Crypto. It was submitted to the NESSIE project, but was not selected.

NUSH

General
Designers	Anatoly Lebedev Alexey Volchkov
First published	2000
Cipher detail
Key sizes	128, 192, or 256 bits
Block sizes	64, 128, or 256 bits
Rounds	9, 17, or 33
Best public cryptanalysis
A linear attack faster than exhaustive search has been found.^[1]

NUSH exists in several different variants, using keys of 128, 192, or 256 bits, and a block size of 64, 128, or 256 bits. The number of rounds is 9, 17, or 33, depending on the block size. The algorithm uses key whitening, but no S-boxes; the only operations it uses are AND, OR, XOR, modular addition, and bit rotation.

It has been shown that linear cryptanalysis can break NUSH with less effort than a brute force attack.^[2]

References

1. Lars Knudsen, Håvard Raddum (2001-03-07). "A first report on Whirlpool, NUSH, SC2000, Noekeon, Two-Track-MAC and RC6" (PDF). Retrieved 2018-09-13.
2. Wenling Wu, Dengguo Feng (23 July 2001). "Linear cryptanalysis of NUSH block cipher". Science China Information Sciences. 45 (1): 59–67. doi:10.1360/02yf9005. ISSN 1009-2757. S2CID 10803906.