A Secure Hash Algorithm with only 8 Folded SHA-1 Steps

We propose a new design principle for construction of iterated cryptographic hash functions: computations in the iterative part of the compression function to start with variables produced in the message expansion part that have complexity level of a random Boolean function. Then we show that to reach the cryptographic strength that will withstand all currently known techniques for finding collisions, much lower number of iterations is necessary. Concretely we use the recently proposed nonlinear technique “Quasigroup Fold” together with the mentioned principle to design a hash function that has only 8 iterative steps. Besides increasing the security, the reference C code for the obtained hash function shows that it is at least 3% faster than original reference code for SHA-1.