Reference : Cryptanalysis of Feistel Networks with Secret Round Functions |
Scientific congresses, symposiums and conference proceedings : Paper published in a book | |||
Engineering, computing & technology : Computer science | |||
http://hdl.handle.net/10993/22278 | |||
Cryptanalysis of Feistel Networks with Secret Round Functions | |
English | |
Biryukov, Alex ![]() | |
Leurent, Gaëtan ![]() | |
Perrin, Léo Paul ![]() | |
Mar-2016 | |
Selected Areas in Cryptography -- SAC 2015, 21st International Conference, Sackville, NB, Canada, August 12-14, 2015, Revised Selected Papers | |
Dunkelman, Orr | |
Keliher, Liam | |
Springer International Publishing | |
Security and Cryptology, 8781 | |
102-121 | |
Yes | |
No | |
International | |
Selected Areas in Cryptography -- SAC 2015 | |
August 12-14, 2015 | |
Sackville | |
Canada | |
[en] Feistel Network ; Yoyo ; Guess-and-Determine | |
[en] Generic distinguishers against Feistel Network with up to 5 rounds exist in the regular setting and up to 6 rounds in a multi-key setting. We present new cryptanalyses against Feistel Networks with 5, 6 and 7 rounds which are not simply distinguishers but actually recover completely the unknown Feistel functions.
When an exclusive-or is used to combine the output of the round function with the other branch, we use the so-called \textit{yoyo game} which we improved using a heuristic based on particular cycle structures. The complexity of a complete recovery is equivalent to $\bigO(2^{2n})$ encryptions where $n$ is the branch size. This attack can be used against 6- and 7-round Feistel Networks in time respectively $\bigO(2^{n2^{n-1}+2n})$ and $\bigO(2^{n2^{n}+2n})$. However when modular addition is used, this attack does not work. In this case, we use an optimized guess-and-determine strategy to attack 5 rounds with complexity $\bigO(2^{n2^{3n/4}})$. Our results are, to the best of our knowledge, the first recovery attacks against generic 5-, 6- and 7-round Feistel Networks. | |
Researchers ; Professionals ; Students | |
http://hdl.handle.net/10993/22278 | |
http://eprint.iacr.org/2015/723 | |
FnR ; FNR4009992 > Alex Biryukov > ACRYPT > Applied Cryptography for the Internet of Things > 01/01/2013 > 31/12/2015 > 2012 |
File(s) associated to this reference | ||||||||||||||
Fulltext file(s):
| ||||||||||||||
All documents in ORBilu are protected by a user license.