| Presentation | 2008-05-16 New Impossible Differentials of CLEFIA Etsuko TSUJIHARA, Maki SHIGERI, Tomoyasu SUZAKI, Takeshi KAWABATA, Yukiyasu TSUNOO, |
|---|---|
| PDF Download Page |  PDF download Page Link |
| Abstract(in Japanese) | (See Japanese page) |
| Abstract(in English) | This paper reports impossible differential cryptanalysis on the 128-bit block cipher CLEFIA that was proposed in 2007. This paper shows new 9-round impossible differentials different from impossible differentials reported in FSE2008, and the result of an impossible differential attack using them. For the case of a 128-bit key, it is possible to apply the impossible differential attack to CLEFIA reduced to 12 rounds. The number of chosen plaintexts required is 2^<111.0> and the time complexity is 2^<111>. For key lengths of 192 bits and 256 bits, it is possible to apply impossible differential attacks to 13-round and 14-round CLEFIA. The respective numbers of chosen plaintexts required are 2^<111.8> and 2^<112.3> and the respective time complexities are 2^<155> and 2^<220>. These attacks can reduce the number of chosen plaintexts for all key lengths. |
| Keyword(in Japanese) | (See Japanese page) |
| Keyword(in English) | CLEFIA / DSM / generalized Feistel structure / impossible differential cryptanalysis / impossible differentials |
| Paper # | ISEC2008-3 |
| Date of Issue |
| Conference Information | |
| Committee | ISEC |
|---|---|
| Conference Date | 2008/5/9(1days) |
| Place (in Japanese) | (See Japanese page) |
| Place (in English) | |
| Topics (in Japanese) | (See Japanese page) |
| Topics (in English) | |
| Chair | |
| Vice Chair | |
| Secretary | |
| Assistant | |
| Paper Information | |
| Registration To | Information Security (ISEC) |
|---|---|
| Language | JPN |
| Title (in Japanese) | (See Japanese page) |
| Sub Title (in Japanese) | (See Japanese page) |
| Title (in English) | New Impossible Differentials of CLEFIA |
| Sub Title (in English) | |
| Keyword(1) | CLEFIA |
| Keyword(2) | DSM |
| Keyword(3) | generalized Feistel structure |
| Keyword(4) | impossible differential cryptanalysis |
| Keyword(5) | impossible differentials |
| 1st Author's Name | Etsuko TSUJIHARA |
| 1st Author's Affiliation | Y.D.K.Co.,Ltd.() |
| 2nd Author's Name | Maki SHIGERI |
| 2nd Author's Affiliation | NEC Software Hokuriku, Ltd. |
| 3rd Author's Name | Tomoyasu SUZAKI |
| 3rd Author's Affiliation | NEC Corporation |
| 4th Author's Name | Takeshi KAWABATA |
| 4th Author's Affiliation | NEC Software Hokuriku, Ltd. |
| 5th Author's Name | Yukiyasu TSUNOO |
| 5th Author's Affiliation | NEC Corporation |
| Date | 2008-05-16 |
| Paper # | ISEC2008-3 |
| Volume (vol) | vol.108 |
| Number (no) | 38 |
| Page | pp.pp.- |
| #Pages | 8 |
| Date of Issue | |