ENCRYPTION/DECRYPTION METHOD AND DEVICE

Abstract

An encryption/decryption method and a device. The method includes: performing rounds of operations based on input data and a key to generate output data, each round of operations processes N blocks of data to generate round output data; in each round of operations, the method further includes: performing random masking based on the N−1 blocks of data and a round key rki of the i-th round to generate first data; performing nonlinear transformation on the first data using a masked S-box to generate second data; performing linear transformation on the second data to generate third data; performing a first XOR operation on a remaining one block of data of the current round and the third data to generate fourth data; performing masking on the fourth data to generate the round output data of the current round.

CPC Classifications