Flaws in Differential Cryptanalysis of Skipjack
- Cite this paper as:
- Granboulan L. (2002) Flaws in Differential Cryptanalysis of Skipjack. In: Matsui M. (eds) Fast Software Encryption. FSE 2001. Lecture Notes in Computer Science, vol 2355. Springer, Berlin, Heidelberg
This paper is motivated by some results presented by Knudsen, Robshaw and Wagner at Crypto’99 , that described many attacks of reduced versions of Skipjack, some of them being erroneous.
Differential cryptanalysis is based on distinguishers, any attack should prove that the events that triggers the analysis has not the same probability for the cipher than for a random function. In particular, the composition of differential for successive parts of a cipher should be done very carefully to lead to an attack.
This revised version of the paper includes the exact computations of some probabilities and repairs the attack of the first half of Skipjack.