Paper 2011/423
Linear Cryptanalysis of PRINTcipher --- Trails and Samples Everywhere
Martin Ågren and Thomas Johansson
Abstract
PRINTcipher is a recent lightweight block cipher designed by Knudsen et al. Some noteworthy characteristics are a burnt-in key, a key-dependent permutation layer and identical round keys. Independent work on PRINTcipher has identified weak key classes that allow for a key recovery --- the obvious countermeasure is to avoid these weak keys at the cost of a small loss of key entropy. This paper identifies several larger classes of weak keys. We show how to distinguish classes of keys and give a $28$-round linear attack applicable to half the keys. We show that there are several similar attacks, each focusing on a specific class of keys. We also observe how some specific properties of PRINTcipher allow us to collect several samples from each plaintext--ciphertext pair. We use this property to construct an attack on $29$-round PRINTcipher applicable to a fraction $2^{-5}$ of the keys.
Note: Substantially revised.
Metadata
- Available format(s)
-
PDF
- Category
- Secret-key cryptography
- Publication info
- Published elsewhere. Submitted
- Keywords
- cryptanalysisblock cipherlinear cryptanalysisfinding sampleskey bit distinguisher
- Contact author(s)
- martin agren @ eit lth se
- History
- 2011-09-30: revised
- 2011-08-12: received
- See all versions
- Short URL
- https://ia.cr/2011/423
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2011/423,
author = {Martin Ågren and Thomas Johansson},
title = {Linear Cryptanalysis of {PRINTcipher} --- Trails and Samples Everywhere},
howpublished = {Cryptology {ePrint} Archive, Paper 2011/423},
year = {2011},
url = {https://eprint.iacr.org/2011/423}
}
