A Novel Method to Design S-Boxes Based on Key-Dependent Permutation Schemes and its Quality Analysis

S-boxes are used in block ciphers as the important nonlinear components. The nonlinearity provides important protection against linear and differential cryptanalysis. The Sboxes used in encryption process could be chosen to be keydependent. In this paper, we have presented four simple algorithms for generation key-dependent S-boxes. For quality analysis of the key-dependent S-boxes, we have proposed eight distance metrics. We have assumed the Matlab function “randperm” as standard of permutation and compared it with permutation possibilities of the proposed algorithms. In the second section we describe four algorithms, which generate keydependent S-boxes. In the third section we analyze eight normalized distance metrics which we have used for evaluation of the quality of the key-dependent generation algorithms. Afterwards, we experimentally investigate the quality of the generated key-dependent S-boxes. Comparison results show that the key-dependent S-boxes have good quality and may be applied in cipher systems. Keywords—data encryption; substitution boxes; generation algorithms; distance metrics; quality analysis