FrogBard-512: Design and Experimental Evaluation of a Four-Voice Permutation-Based Hash Function (opens in new tab)

FrogBard-512 is an experimental 512-bit hash function based on a custom 2048-bit permutation organized as four 512-bit voices. The sequential mode uses a 1024-bit rate, a 1024-bit capacity, 128-byte message blocks, and a 16-round permutation. Each round combines public round constants, four AES-derived affine-equivalent byte substitutions, ARX quarter-rounds, a parity-dependent cross-voice mixing layer, and fixed lane permutations. The design al...