Instruction sequence expressions for the secure hash algorithm SHA-256

Abstract

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

14 pages; several minor errors corrected; counting error corrected; instruction sequence fault repaired; misunderstanding cleared up; a minor error corrected; 15 pages, presentation improved, a minor error corrected. preliminaries have text overlap with arXiv:1301.3297

References in corpus (3)

• On algorithmic equivalence of instruction sequences for computing bit string functions
• An Instruction Sequence Semigroup with Involutive Anti-Automorphisms
• Instruction sequences expressing multiplication algorithms

Cited by in corpus (5)

• On algorithmic equivalence of instruction sequences for computing bit string functions
• Instruction sequences expressing multiplication algorithms
• Long multiplication by instruction sequences with backward jump instructions
• Program algebra for Turing-machine programs
• Program algebra for random access machine programs