Paper 2019/509
New Slide Attacks on Almost Self-Similar Ciphers
Orr Dunkelman, Nathan Keller, Noam Lasry, and Adi Shamir
Abstract
The slide attack is a powerful cryptanalytic tool which has the unusual property that it can break iterated block ciphers with a complexity that does not depend on their number of rounds. However, it requires complete self similarity in the sense that all the rounds must be identical. While this can be the case in Feistel structures, this rarely happens in SP networks since the last round must end with an additional post-whitening subkey. In addition, in many SP networks the final round has additional asymmetries -- for example, in AES the last round omits the MixColumns operation. Such asymmetry in the last round can make it difficult to utilize most of the advanced tools which were developed for slide attacks, such as deriving from one slid pair additional slid pairs by repeatedly re-encrypting their ciphertexts.
In this paper we overcome this "last round problem" by developing four new types of slide attacks. We demonstrate their power by applying them to many types of AES-like structures (with and without
linear mixing in the last round, with known or secret S-boxes, with 1,2 and 3 periodicity in their subkeys, etc). In most of these cases, the time complexity of our attack is close to
Metadata
- Available format(s)
-
PDF
- Category
- Secret-key cryptography
- Publication info
- Preprint. MINOR revision.
- Keywords
- Slide attack1-KSA1K-AESSlid setsHypercuber of slid pairssuggestive structuresSubstitution slide
- Contact author(s)
- orrd @ cs haifa ac il
- History
- 2019-10-04: revised
- 2019-05-20: received
- See all versions
- Short URL
- https://ia.cr/2019/509
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2019/509, author = {Orr Dunkelman and Nathan Keller and Noam Lasry and Adi Shamir}, title = {New Slide Attacks on Almost Self-Similar Ciphers}, howpublished = {Cryptology {ePrint} Archive, Paper 2019/509}, year = {2019}, url = {https://eprint.iacr.org/2019/509} }