On the problem of finding linear approximations and cryptanalysis of Pomaranch Version 2
(2007) 13th International Workshop, SAC 2006 4356. p.220-233- Abstract
- We give a simple algorithm that can find biased linear approximations of nonlinear building blocks. The algorithm is useful if the building block is relatively small and exhaustive search is possible. Instead of searching all possible linear relations individually, we show how the most biased relation can be found in just a few steps. As an example we show how we can find a biased relation in the output bits of the stream cipher Pomaranch Version 2, a tweaked variant of Pomaranch, resulting in both distinguishing and key recovery attacks. These attacks will break both the 128-bit variant and the 80-bit variant of the cipher with complexity faster than exhaustive key search.
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/603346
- author
- Hell, Martin
LU
and Johansson, Thomas
LU
- organization
- publishing date
- 2007
- type
- Chapter in Book/Report/Conference proceeding
- publication status
- published
- subject
- keywords
- cryptanalysis, stream ciphers, Pomaranch, linear approximation
- host publication
- Selected Areas in Cryptography/Lecture notes in computer science)
- volume
- 4356
- pages
- 220 - 233
- publisher
- Springer
- conference name
- 13th International Workshop, SAC 2006
- conference location
- Montreal, Canada
- conference dates
- 2006-08-17 - 2006-08-18
- external identifiers
-
- wos:000251036300016
- scopus:38149026933
- ISSN
- 0302-9743
- 1611-3349
- ISBN
- 978-3-540-74461-0
- DOI
- 10.1007/978-3-540-74462-7
- language
- English
- LU publication?
- yes
- id
- d769d545-dec3-4330-86fc-1ad7a953c745 (old id 603346)
- date added to LUP
- 2016-04-01 12:20:00
- date last changed
- 2025-01-02 14:13:04
@inproceedings{d769d545-dec3-4330-86fc-1ad7a953c745, abstract = {{We give a simple algorithm that can find biased linear approximations of nonlinear building blocks. The algorithm is useful if the building block is relatively small and exhaustive search is possible. Instead of searching all possible linear relations individually, we show how the most biased relation can be found in just a few steps. As an example we show how we can find a biased relation in the output bits of the stream cipher Pomaranch Version 2, a tweaked variant of Pomaranch, resulting in both distinguishing and key recovery attacks. These attacks will break both the 128-bit variant and the 80-bit variant of the cipher with complexity faster than exhaustive key search.}}, author = {{Hell, Martin and Johansson, Thomas}}, booktitle = {{Selected Areas in Cryptography/Lecture notes in computer science)}}, isbn = {{978-3-540-74461-0}}, issn = {{0302-9743}}, keywords = {{cryptanalysis; stream ciphers; Pomaranch; linear approximation}}, language = {{eng}}, pages = {{220--233}}, publisher = {{Springer}}, title = {{On the problem of finding linear approximations and cryptanalysis of Pomaranch Version 2}}, url = {{http://dx.doi.org/10.1007/978-3-540-74462-7}}, doi = {{10.1007/978-3-540-74462-7}}, volume = {{4356}}, year = {{2007}}, }