Abstract
IDEA is a 64-bit block cipher with 128-bit keys which was introduced by Lai and Massey in 1991. The best previously published attack on IDEA could only handle 6 of its 8.5-rounds. In this paper, we combine a highly optimized meet-in-the-middle attack with a keyless version of the Biryukov–Demirci relation to obtain a greatly improved attack on 6-round IDEA which requires only two known plaintexts, and the first key recovery attacks on versions of IDEA with 6.5 to 8.5 rounds.
Original language | English |
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Pages (from-to) | 209-239 |
Number of pages | 31 |
Journal | Journal of Cryptology |
Volume | 28 |
Issue number | 2 |
DOIs | |
State | Published - Apr 2015 |
Bibliographical note
Publisher Copyright:© 2013, International Association for Cryptologic Research.
Funding
O. Dunkelman was supported in part by the German–Israeli Foundation for Scientific Research and Development through grant No. 2282-2222.6/2011.
Funders | Funder number |
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German-Israeli Foundation for Scientific Research and Development | |
German-Israeli Foundation for Scientific Research and Development | 2282-2222.6/2011 |
Keywords
- Biryukov–Demirci relation
- Cryptanalysis
- IDEA
- Zero-in-the-Middle attack