Merging the camellia, SMS4 and AES S-boxes in a single S-box with composite bases

© Springer International Publishing Switzerland 2015.For some block ciphers such as AES, substitution box (S-box) based on multiplicative inversion is the most complex operation. Efficient constructions should be found for optimizing features like the area, the amount of memory, etc. Composite representations in finite fields are the prominent ways to represent the multiplicative inverse operation in a compact way. In this manuscript, different constructions based on composite fields are shown to represent the AES, Camellia and SMS4 S-boxes. Mainly, this manuscript describes representations in GF((24)2). From these representations, an evaluation is performed to choose those feasible solutions that help to merge the AES, Camellia and SMS4 Sboxes into a single one. For instance, by using merged matrices and the same composite polynomial basis, it is possible to reduce from 172 XOR gates (independent matrices) to 146 XOR gates (merged matrices).

Merging the camellia, SMS4 and AES S-boxes in a single S-box with composite bases Chapter in Scopus