A method for designing dynamical S-boxes based on hyperchaotic Lorenz system

This paper is devoted to presenting a new method for generating dynamically cryptographically S-boxes based on a four-dimensional hyperchaotic Lorenz system. Within the algorithm, the initial condition is employed to drive the hyperchaotic Lorenz system to generate a chaotic sequence which is used to construct S-boxes. With different system conditions, many of distinct S-boxes can be obtained dynamically. Some cryptographic properties for a good S-box such as bijection, nonlinearity, SAC, BIC and differential approximation probability are found to hold in the obtained S-boxes from the proposed method. The analytic results indicate that all the criteria for designing robust S-boxes can be achieved. The comparison of the proposed S-box generating method with other chaos-based schemes indicates that our S-boxes have a better performance with respect to some properties.