Improved Cryptanalysis of MISTY1
نویسنده
چکیده
The block cipher MISTY1 [9] proposed for the NESSIE project [11] is a Feistel network augmented with key-dependent linear FL functions. The proposal allows a variable number of rounds provided that it is a multiple of four. Here we present a new attack – the Slicing Attack – on the 4-round version, which makes use of the special structure and position of these key-dependent linear FL functions. While the FL functions were introduced to make attacks harder, they also present a subtle weakness in the 4-round version of the cipher.
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