crypto-keygen-suite/keyGen/keygenerators/serpentKeyGenerator.js

Key generation utilities for cryptographic operations. YES I RENAMED IT. SIX STATE PROTOCOL!!! See its folder for all <3

import crypto from 'crypto';

function rotl32(x, n) {
  return ((x << n) | (x >>> (32 - n))) >>> 0;
}

function bufferToWords(buf) {
  const words = [];
  for (let i = 0; i < buf.length; i += 4) {
    words.push(buf.readUInt32LE(i));
  }
  return words;
}

function wordsToBuffer(words) {
  const buf = Buffer.alloc(words.length * 4);
  words.forEach((w, i) => buf.writeUInt32LE(w, i * 4));
  return buf;
}

const S_BOXES = [
  [3, 8, 15, 1, 10, 6, 5, 11, 14, 13, 4, 7, 9, 0, 12, 2],
  [15, 12, 2, 7, 9, 0, 5, 10, 1, 11, 14, 8, 6, 13, 3, 4],
  [8, 6, 7, 9, 3, 12, 10, 15, 13, 1, 14, 4, 0, 11, 5, 2],
  [0, 15, 11, 8, 12, 9, 6, 3, 13, 1, 2, 4, 10, 7, 5, 14],
  [1, 15, 8, 3, 12, 0, 11, 6, 2, 5, 14, 9, 7, 10, 4, 13],
  [15, 5, 2, 11, 4, 10, 9, 12, 0, 3, 14, 8, 13, 6, 7, 1],
  [7, 2, 12, 5, 8, 4, 6, 11, 14, 9, 1, 15, 13, 3, 10, 0],
  [1, 13, 15, 0, 14, 8, 2, 11, 7, 4, 12, 10, 9, 3, 5, 6],
];

function applySBoxToWord(word, sbox) {
  let result = 0;
  for (let nibble = 0; nibble < 8; nibble++) {
    const shift = nibble * 4;
    const val = (word >>> shift) & 0xF;
    const sub = S_BOXES[sbox][val];
    result |= (sub << shift);
  }
  return result >>> 0;
}

function generateSerpentKey() {
  return crypto.randomBytes(32);
}

function keySchedule(keyBuf) {
  const keyWords = bufferToWords(keyBuf);

  while (keyWords.length < 8) {
    keyWords.push(0);
  }

  const W = new Uint32Array(132);

  for (let i = 0; i < 8; i++) {
    W[i] = keyWords[i];
  }

  for (let i = 8; i < 132; i++) {
    let temp = W[i-8] ^ W[i-5] ^ W[i-3] ^ W[i-1] ^ 0x9e3779b9 ^ i;
    W[i] = rotl32(temp, 11);
  }

  const roundKeys = [];
  for (let i = 0; i < 33; i++) {
    const rkWords = [];
    for (let j = 0; j < 4; j++) {
      const word = W[4*i + j];
      rkWords.push(applySBoxToWord(word, (32 - i) % 8));
    }
    roundKeys.push(wordsToBuffer(rkWords));
  }

  return roundKeys;
}

function generateSerpentKeyAndSchedule() {
  const key = generateSerpentKey();
  const roundKeys = keySchedule(key);
  return { key, roundKeys };
}

const result = generateSerpentKeyAndSchedule();
console.log("Generated Serpent Key (HEX):", result.key.toString('hex'));
console.log("Round Keys (HEX):");
result.roundKeys.forEach((rk, i) => console.log(`Round ${i}: ${rk.toString('hex')}`));