md5.js

const add32 = function (a, b) {
  return a + b & 0xFFFFFFFF;
};

function md5cycle(x, k) {
  var a = x[0], b = x[1], c = x[2], d = x[3];

  a = ff(a, b, c, d, k[0], 7, -680876936);
  d = ff(d, a, b, c, k[1], 12, -389564586);
  c = ff(c, d, a, b, k[2], 17, 606105819);
  b = ff(b, c, d, a, k[3], 22, -1044525330);
  a = ff(a, b, c, d, k[4], 7, -176418897);
  d = ff(d, a, b, c, k[5], 12, 1200080426);
  c = ff(c, d, a, b, k[6], 17, -1473231341);
  b = ff(b, c, d, a, k[7], 22, -45705983);
  a = ff(a, b, c, d, k[8], 7, 1770035416);
  d = ff(d, a, b, c, k[9], 12, -1958414417);
  c = ff(c, d, a, b, k[10], 17, -42063);
  b = ff(b, c, d, a, k[11], 22, -1990404162);
  a = ff(a, b, c, d, k[12], 7, 1804603682);
  d = ff(d, a, b, c, k[13], 12, -40341101);
  c = ff(c, d, a, b, k[14], 17, -1502002290);
  b = ff(b, c, d, a, k[15], 22, 1236535329);

  a = gg(a, b, c, d, k[1], 5, -165796510);
  d = gg(d, a, b, c, k[6], 9, -1069501632);
  c = gg(c, d, a, b, k[11], 14, 643717713);
  b = gg(b, c, d, a, k[0], 20, -373897302);
  a = gg(a, b, c, d, k[5], 5, -701558691);
  d = gg(d, a, b, c, k[10], 9, 38016083);
  c = gg(c, d, a, b, k[15], 14, -660478335);
  b = gg(b, c, d, a, k[4], 20, -405537848);
  a = gg(a, b, c, d, k[9], 5, 568446438);
  d = gg(d, a, b, c, k[14], 9, -1019803690);
  c = gg(c, d, a, b, k[3], 14, -187363961);
  b = gg(b, c, d, a, k[8], 20, 1163531501);
  a = gg(a, b, c, d, k[13], 5, -1444681467);
  d = gg(d, a, b, c, k[2], 9, -51403784);
  c = gg(c, d, a, b, k[7], 14, 1735328473);
  b = gg(b, c, d, a, k[12], 20, -1926607734);

  a = hh(a, b, c, d, k[5], 4, -378558);
  d = hh(d, a, b, c, k[8], 11, -2022574463);
  c = hh(c, d, a, b, k[11], 16, 1839030562);
  b = hh(b, c, d, a, k[14], 23, -35309556);
  a = hh(a, b, c, d, k[1], 4, -1530992060);
  d = hh(d, a, b, c, k[4], 11, 1272893353);
  c = hh(c, d, a, b, k[7], 16, -155497632);
  b = hh(b, c, d, a, k[10], 23, -1094730640);
  a = hh(a, b, c, d, k[13], 4, 681279174);
  d = hh(d, a, b, c, k[0], 11, -358537222);
  c = hh(c, d, a, b, k[3], 16, -722521979);
  b = hh(b, c, d, a, k[6], 23, 76029189);
  a = hh(a, b, c, d, k[9], 4, -640364487);
  d = hh(d, a, b, c, k[12], 11, -421815835);
  c = hh(c, d, a, b, k[15], 16, 530742520);
  b = hh(b, c, d, a, k[2], 23, -995338651);

  a = ii(a, b, c, d, k[0], 6, -198630844);
  d = ii(d, a, b, c, k[7], 10, 1126891415);
  c = ii(c, d, a, b, k[14], 15, -1416354905);
  b = ii(b, c, d, a, k[5], 21, -57434055);
  a = ii(a, b, c, d, k[12], 6, 1700485571);
  d = ii(d, a, b, c, k[3], 10, -1894986606);
  c = ii(c, d, a, b, k[10], 15, -1051523);
  b = ii(b, c, d, a, k[1], 21, -2054922799);
  a = ii(a, b, c, d, k[8], 6, 1873313359);
  d = ii(d, a, b, c, k[15], 10, -30611744);
  c = ii(c, d, a, b, k[6], 15, -1560198380);
  b = ii(b, c, d, a, k[13], 21, 1309151649);
  a = ii(a, b, c, d, k[4], 6, -145523070);
  d = ii(d, a, b, c, k[11], 10, -1120210379);
  c = ii(c, d, a, b, k[2], 15, 718787259);
  b = ii(b, c, d, a, k[9], 21, -343485551);

  x[0] = add32(a, x[0]);
  x[1] = add32(b, x[1]);
  x[2] = add32(c, x[2]);
  x[3] = add32(d, x[3]);

}

function cmn(q, a, b, x, s, t) {
  a = add32(add32(a, q), add32(x, t));
  return add32(a << s | a >>> 32 - s, b);
}

function ff(a, b, c, d, x, s, t) {
  return cmn(b & c | ~b & d, a, b, x, s, t);
}

function gg(a, b, c, d, x, s, t) {
  return cmn(b & d | c & ~d, a, b, x, s, t);
}

function hh(a, b, c, d, x, s, t) {
  return cmn(b ^ c ^ d, a, b, x, s, t);
}

function ii(a, b, c, d, x, s, t) {
  return cmn(c ^ (b | ~d), a, b, x, s, t);
}

function md51(s) {
  var n = s.length, state = [1732584193, -271733879, -1732584194, 271733878], i;

  for (i = 64; i <= n; i += 64) {
    md5cycle(state, md5blk(s.substring(i - 64, i)));
  }

  s = s.substring(i - 64);
  var tail = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0];

  for (i = 0; i < s.length; i++) {
    tail[i >> 2] |= s.charCodeAt(i) << (i % 4 << 3);
  }

  tail[i >> 2] |= 0x80 << (i % 4 << 3);

  if (i > 55) {
    md5cycle(state, tail);
    for (i = 0; i < 16; i++) { tail[i] = 0; }
  }

  tail[14] = n * 8;
  md5cycle(state, tail);

  return state;
}

function md5blk(s) {
  let md5blks = [], i;
  for (i = 0; i < 64; i += 4) {
    md5blks[i >> 2] = s.charCodeAt(i)
      + (s.charCodeAt(i + 1) << 8)
      + (s.charCodeAt(i + 2) << 16)
      + (s.charCodeAt(i + 3) << 24);
  }
  return md5blks;
}

const hex_chr = '0123456789abcdef'.split('');

function rhex(n) {
  let s = '', j = 0;
  for (; j < 4; j++) {
    s += hex_chr[n >> j * 8 + 4 & 0x0F]
    + hex_chr[n >> j * 8 & 0x0F];
  }
  return s;
}

function hex(x) {
  for (let i = 0; i < x.length; i++) { x[i] = rhex(x[i]); }
  return x.join('');
}

function md5(s) {
  return hex(md51(s));
}


export default md5;