Chaotic Hash Function Based on Tandem-DM Construction

Conventional chaotic hash functions adopt a number of iterations of chaotic map and a large number of floating point calculations, thus the implement of these hash functions require a great many resources. This kind of hash functions are hard to implement on the equipments which have limited resources, such as mobile phone and smart cards. In this paper, a novel hash algorithm is proposed which combines the advantage of both chaotic system and Tandem-DM compression structure. The proposal follows the usual Merkle-Damgard construction while compression function adopts the Tandem DM compression structure. Block cipher used in the Tandem DM compression function is replaced by the discretized chaotic map network (DCMN). The proposed hash function runs in the integer field and needs fewer computations. Compared with other chaotic hash functions, the algorithm inherits the efficiency of the conventional hash function while improves the security of hash function. Theoretical and simulation results show that the proposed hash algorithm has strong diffusion and confusion capability and good collision resistance, as required by practical hash functions.