Block ciphers use Substitution boxes (S-boxes) to create confusion into the cryptosystems. For resisting the known attacks on these cryptosystems, the following criteria for functions are mandatory: low differential uniformity, high nonlinearity and not low algebraic degree. Bijectivity is also necessary if the cipher is a Substitution-Permutation Network, and balancedness makes a Feistel cipher lighter. It is wellknown that almost perfect nonlinear (APN) functions have the lowest differential uniformity 2 (the values of differential uniformity being always even) and the existence of APN bijections over F2n for even n ≥ 8 is a big open problem. In real practical applications, differentially 4-uniform bijections can be used as S-boxes when the dimension is even. For example, the AES uses a differentially 4-uniform bijection over F28. In this paper, we first propose a method for constructing a large family of differentially 4-uniform bijections in even dimensions. This method can generate at least (2n-3 – [2(n-1)/2-1] – 1) · 22n-1 such bijections having maximum algebraic degree n-1. Furthermore, we exhibit a subclass of functions having high nonlinearity and being CCZ-inequivalent to all known differentially 4-uniform power bijections and to quadratic functions.
CITATION STYLE
Carlet, C., Tang, D., Tang, X., & Liao, Q. (2014). New construction of differentially 4-uniform bijections. In Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) (Vol. 8567, pp. 22–38). Springer Verlag. https://doi.org/10.1007/978-3-319-12087-4_2
Mendeley helps you to discover research relevant for your work.