ARIA ENCODING/DECODING APPARATUS AND METHOD AND METHOD FOR GENEARATING INITIALIZATION KEYS FOR THE SAME

摘要

An apparatus and a method of ARIA encoding/decoding and a method for generating an initial key for the same are provided to reduce a size of a circuit by performing a substitution operation through different kinds of four S boxes. An apparatus of ARIA encoding/decoding iteratively includes a first register(12), a second register(13), an XOR processor(14), a substituting unit(15), a diffusing unit(16), and a controlling unit(18). The first register stores input data or an intermediate calculation value according to a first control signal. The second register stores a round key inputted in every round. The XOR operator XOR-operates the values stored in the first and second registers. The substituting unit substitutes the XOR-operated result according to ARIA substitution algorithm. The diffusing unit diffuses the substitution result of the substituting unit according to ARIA diffusion algorithm in case that it is not a last round. The controlling unit outputs the first control signal for outputting an output of the diffusing unit in case that it is not the last round, and an output of the substituting unit as the intermediate calculation value in case that it is the last round, and outputs an output of the XOR operator as the ARIA encoded/decoded result.