index.js 4.5 KB
Newer Older
liang ce committed
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146
'use strict'
var inherits = require('inherits')
var HashBase = require('hash-base')
var Buffer = require('safe-buffer').Buffer

var ARRAY16 = new Array(16)

function MD5 () {
  HashBase.call(this, 64)

  // state
  this._a = 0x67452301
  this._b = 0xefcdab89
  this._c = 0x98badcfe
  this._d = 0x10325476
}

inherits(MD5, HashBase)

MD5.prototype._update = function () {
  var M = ARRAY16
  for (var i = 0; i < 16; ++i) M[i] = this._block.readInt32LE(i * 4)

  var a = this._a
  var b = this._b
  var c = this._c
  var d = this._d

  a = fnF(a, b, c, d, M[0], 0xd76aa478, 7)
  d = fnF(d, a, b, c, M[1], 0xe8c7b756, 12)
  c = fnF(c, d, a, b, M[2], 0x242070db, 17)
  b = fnF(b, c, d, a, M[3], 0xc1bdceee, 22)
  a = fnF(a, b, c, d, M[4], 0xf57c0faf, 7)
  d = fnF(d, a, b, c, M[5], 0x4787c62a, 12)
  c = fnF(c, d, a, b, M[6], 0xa8304613, 17)
  b = fnF(b, c, d, a, M[7], 0xfd469501, 22)
  a = fnF(a, b, c, d, M[8], 0x698098d8, 7)
  d = fnF(d, a, b, c, M[9], 0x8b44f7af, 12)
  c = fnF(c, d, a, b, M[10], 0xffff5bb1, 17)
  b = fnF(b, c, d, a, M[11], 0x895cd7be, 22)
  a = fnF(a, b, c, d, M[12], 0x6b901122, 7)
  d = fnF(d, a, b, c, M[13], 0xfd987193, 12)
  c = fnF(c, d, a, b, M[14], 0xa679438e, 17)
  b = fnF(b, c, d, a, M[15], 0x49b40821, 22)

  a = fnG(a, b, c, d, M[1], 0xf61e2562, 5)
  d = fnG(d, a, b, c, M[6], 0xc040b340, 9)
  c = fnG(c, d, a, b, M[11], 0x265e5a51, 14)
  b = fnG(b, c, d, a, M[0], 0xe9b6c7aa, 20)
  a = fnG(a, b, c, d, M[5], 0xd62f105d, 5)
  d = fnG(d, a, b, c, M[10], 0x02441453, 9)
  c = fnG(c, d, a, b, M[15], 0xd8a1e681, 14)
  b = fnG(b, c, d, a, M[4], 0xe7d3fbc8, 20)
  a = fnG(a, b, c, d, M[9], 0x21e1cde6, 5)
  d = fnG(d, a, b, c, M[14], 0xc33707d6, 9)
  c = fnG(c, d, a, b, M[3], 0xf4d50d87, 14)
  b = fnG(b, c, d, a, M[8], 0x455a14ed, 20)
  a = fnG(a, b, c, d, M[13], 0xa9e3e905, 5)
  d = fnG(d, a, b, c, M[2], 0xfcefa3f8, 9)
  c = fnG(c, d, a, b, M[7], 0x676f02d9, 14)
  b = fnG(b, c, d, a, M[12], 0x8d2a4c8a, 20)

  a = fnH(a, b, c, d, M[5], 0xfffa3942, 4)
  d = fnH(d, a, b, c, M[8], 0x8771f681, 11)
  c = fnH(c, d, a, b, M[11], 0x6d9d6122, 16)
  b = fnH(b, c, d, a, M[14], 0xfde5380c, 23)
  a = fnH(a, b, c, d, M[1], 0xa4beea44, 4)
  d = fnH(d, a, b, c, M[4], 0x4bdecfa9, 11)
  c = fnH(c, d, a, b, M[7], 0xf6bb4b60, 16)
  b = fnH(b, c, d, a, M[10], 0xbebfbc70, 23)
  a = fnH(a, b, c, d, M[13], 0x289b7ec6, 4)
  d = fnH(d, a, b, c, M[0], 0xeaa127fa, 11)
  c = fnH(c, d, a, b, M[3], 0xd4ef3085, 16)
  b = fnH(b, c, d, a, M[6], 0x04881d05, 23)
  a = fnH(a, b, c, d, M[9], 0xd9d4d039, 4)
  d = fnH(d, a, b, c, M[12], 0xe6db99e5, 11)
  c = fnH(c, d, a, b, M[15], 0x1fa27cf8, 16)
  b = fnH(b, c, d, a, M[2], 0xc4ac5665, 23)

  a = fnI(a, b, c, d, M[0], 0xf4292244, 6)
  d = fnI(d, a, b, c, M[7], 0x432aff97, 10)
  c = fnI(c, d, a, b, M[14], 0xab9423a7, 15)
  b = fnI(b, c, d, a, M[5], 0xfc93a039, 21)
  a = fnI(a, b, c, d, M[12], 0x655b59c3, 6)
  d = fnI(d, a, b, c, M[3], 0x8f0ccc92, 10)
  c = fnI(c, d, a, b, M[10], 0xffeff47d, 15)
  b = fnI(b, c, d, a, M[1], 0x85845dd1, 21)
  a = fnI(a, b, c, d, M[8], 0x6fa87e4f, 6)
  d = fnI(d, a, b, c, M[15], 0xfe2ce6e0, 10)
  c = fnI(c, d, a, b, M[6], 0xa3014314, 15)
  b = fnI(b, c, d, a, M[13], 0x4e0811a1, 21)
  a = fnI(a, b, c, d, M[4], 0xf7537e82, 6)
  d = fnI(d, a, b, c, M[11], 0xbd3af235, 10)
  c = fnI(c, d, a, b, M[2], 0x2ad7d2bb, 15)
  b = fnI(b, c, d, a, M[9], 0xeb86d391, 21)

  this._a = (this._a + a) | 0
  this._b = (this._b + b) | 0
  this._c = (this._c + c) | 0
  this._d = (this._d + d) | 0
}

MD5.prototype._digest = function () {
  // create padding and handle blocks
  this._block[this._blockOffset++] = 0x80
  if (this._blockOffset > 56) {
    this._block.fill(0, this._blockOffset, 64)
    this._update()
    this._blockOffset = 0
  }

  this._block.fill(0, this._blockOffset, 56)
  this._block.writeUInt32LE(this._length[0], 56)
  this._block.writeUInt32LE(this._length[1], 60)
  this._update()

  // produce result
  var buffer = Buffer.allocUnsafe(16)
  buffer.writeInt32LE(this._a, 0)
  buffer.writeInt32LE(this._b, 4)
  buffer.writeInt32LE(this._c, 8)
  buffer.writeInt32LE(this._d, 12)
  return buffer
}

function rotl (x, n) {
  return (x << n) | (x >>> (32 - n))
}

function fnF (a, b, c, d, m, k, s) {
  return (rotl((a + ((b & c) | ((~b) & d)) + m + k) | 0, s) + b) | 0
}

function fnG (a, b, c, d, m, k, s) {
  return (rotl((a + ((b & d) | (c & (~d))) + m + k) | 0, s) + b) | 0
}

function fnH (a, b, c, d, m, k, s) {
  return (rotl((a + (b ^ c ^ d) + m + k) | 0, s) + b) | 0
}

function fnI (a, b, c, d, m, k, s) {
  return (rotl((a + ((c ^ (b | (~d)))) + m + k) | 0, s) + b) | 0
}

module.exports = MD5