Instruction sequence expressions for the secure hash algorithm SHA-256

摘要

The secure hash function SHA-256 is a function on bit strings. This meansthat its restriction to the bit strings of any given length can be computed bya finite instruction sequence that contains only instructions to set and getthe content of Boolean registers, forward jump instructions, and a terminationinstruction. We describe such instruction sequences for the restrictions to bitstrings of the different possible lengths by means of uniform terms from analgebraic theory.