Paper 2001/068 Original: eprint.iacr.org/2001/068 ↗
SQUARE Attacks on Reduced-Round PES and IDEA Block Ciphers
Abstract
This paper reports on variants of the Square attack applied to reduced-round versions of the PES and IDEA block ciphers. Attacks on 2.5 rounds of IDEA require $3\cdot 2^{16}$ chosen-plaintexts and recover 78 key bits. A new kind of attack, the Square related-key attack, is applied on 2.5 rounds of IDEA and recovers 32 key bits, with 2 chosen-plaintexts and $2^{17}$ related keys. Similar results hold for 2.5 rounds of PES. Implementations of the attacks on 32-bit block mini-versions of both ciphers confirmed the expected computational complexity. Although our attacks do not improve on previous approaches, this report shows new variants of the Square attack on word-oriented block ciphers like IDEA and PES.
Metadata
- Available format(s)
PDF- Category
- Secret-key cryptography
- Publication info
- Preprint.
- History
- 2001-08-22: last updated
- 2001-08-14: published
- Short URL
- https://ia.cr/2001/068
- License
- https://creativecommons.org/licenses/by/4.0/
BibTeX
@misc{cryptoeprint:2001/068,
author = {J. Nakahara Jr and P. S. L. M. Barreto and B. Preneel and J. Vandewalle and H. Y. Kim},
title = {SQUARE Attacks on Reduced-Round PES and IDEA Block Ciphers},
howpublished = {Cryptology {ePrint} Archive, Paper 2001/068},
year = {2001},
url = {https://eprint.iacr.org/2001/068}
}