Security Analysis of BLAKE-32 Based on Differential Properties

Hash function BLAKE is a new standard candidate algorithm that is selected for the second round of SHA-3 competition by NIST. It is a new type of Merkle-Damgard iterative algorithm and its internal structure adopts local wide-pipe technology. By observing the computing process of the G function in algorithm, we study the reversibility properties of G. This paper exploits some flaws of message permutation and carries out a detailed analysis for differential features of input-output variables in G function and its inverse function by introducing differential analysis ideas. Applying meet-in-the-middle technology and differential properties of G function, we analyze the security of BLAKE-32. The results show that BLAKE has a strong resistance capability to differential attacks.