HAVAL is a hash function proposed by Zheng et al.in 1992,including 3-,4-and 5-pass versions.We improve pseudo-preimage and preimage attacks on 3-pass HAVAL at the complexity of 2 172 and 2 209.6,respectively,as compared to the previous best known results:2 192 and 2 225 by Sasaki et al.in 2008.We extend the skip interval for partial-patching and apply the initial structure technique to find the better message chunks,and combine the indirect-partial-matching,partial-fixing and multi-neutral-word partial-fixing techniques to improve the attacks based on the meet-in-the-middle method.These are the best pseudo-preimage and preimage attacks on 3-pass HAVAL.
Keccak is one of the five hash functions selected for the final round of the SHA-3 competition,and its inner primitive is a permutation called Keccak-f.In this paper,we observe that for the inverse of the only nonlinear transformation in Keccak-f,the algebraic degree of any output coordinate and the one of the product of any two output coordinates are both 3,which is 2 less than its size of 5.Combining this observation with a proposition on the upper bound of the degree of iterated permutations,we improve the zero-sum distinguisher for the Keccak-f permutation with full 24 rounds by lowering the size of the zero-sum partition from 21590 to 21575.
