Design of Chaotic Hash Function Based on Nonlinear Digital Filter

Based on the chaotic characteristics of nonlinear digital filter with changeable coefficients （NDF）,such as the n-dimensional uniform distribution and ergodicity,a chaotic Hash function construction scheme based on NDF is proposed.In the scheme,the message to be hashed is injected into the chaotic trajectory of NDF by parameter modulation,and the Hash value is obtained by means of linear transform on the iteration trajectory.In addition,the initial conditions of NDF and its perturbation map are used as secret key.The results show that proposed algorithm is efficient and more secure than other single-chaos-based Hash algorithms.Moreover,due to non-complex arithmetic operations in the proposed filter structure,it is easy to implement than other chaotic Hash algorithms based on composite system.