Analysis of Building Blocks in SHA-256
A. Arul Lawrence Selvakumar, C. Suresh Gnanadhas · Research Journal of Applied Sciences Engineering and Technology · 2009
In this study, we analyse the role of some of the building blocks in SHA-256. We show that the disturbance correction strategy is applicable to the SHA-256 architecture and we prove that functions Σ, σ are vital for the security of SHA-256 by showing that for a variant without them it is possible to find collisions with complexity 264 hash operations. As a step towards an analysis of the full function, we present the results of our experiments on Hamming weights of expanded messages for different variants of the message expansion and show that there exist low-weight expanded mes sages for XOR-linearised variants.