text: /* 
       * A JavaScript implementation of the RSA Data Security, Inc. MD5 Message 
       * Digest Algorithm, as defined in RFC 1321. 
       * Version 1.1 Copyright (C) Paul Johnston 1999 - 2002. 
       * Code also contributed by Greg Holt 
       * See http://pajhome.org.uk/site/legal.html for details. 
       */
  
  /* 
   * Add integers, wrapping at 2^32. This uses 16-bit operations internally 
   * to work around bugs in some JS interpreters. 
   */
  function safe_add(x, y) {
    var lsw = (x & 0xFFFF) + (y & 0xFFFF)
    var msw = (x >> 16) + (y >> 16) + (lsw >> 16)
    return (msw << 16) | (lsw & 0xFFFF)
  }
  
  /* 
   * Bitwise rotate a 32-bit number to the left. 
   */
  function rol(num, cnt) {
    return (num << cnt) | (num >>> (32 - cnt))
  }
  
  /* 
   * These functions implement the four basic operations the algorithm uses. 
   */
  function cmn(q, a, b, x, s, t) {
    return safe_add(rol(safe_add(safe_add(a, q), safe_add(x, t)), 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)
  }
  
  /* 
   * Calculate the MD5 of an array of little-endian words, producing an array 
   * of little-endian words. 
   */
  function coreMD5(x) {
    var a = 1732584193
    var b = -271733879
    var c = -1732584194
    var d = 271733878
  
    for (var i = 0; i < x.length; i += 16) {
      var olda = a
      var oldb = b
      var oldc = c
      var oldd = d
  
      a = ff(a, b, c, d, x[i + 0], 7, -680876936)
      d = ff(d, a, b, c, x[i + 1], 12, -389564586)
      c = ff(c, d, a, b, x[i + 2], 17, 606105819)
      b = ff(b, c, d, a, x[i + 3], 22, -1044525330)
      a = ff(a, b, c, d, x[i + 4], 7, -176418897)
      d = ff(d, a, b, c, x[i + 5], 12, 1200080426)
      c = ff(c, d, a, b, x[i + 6], 17, -1473231341)
      b = ff(b, c, d, a, x[i + 7], 22, -45705983)
      a = ff(a, b, c, d, x[i + 8], 7, 1770035416)
      d = ff(d, a, b, c, x[i + 9], 12, -1958414417)
      c = ff(c, d, a, b, x[i + 10], 17, -42063)
      b = ff(b, c, d, a, x[i + 11], 22, -1990404162)
      a = ff(a, b, c, d, x[i + 12], 7, 1804603682)
      d = ff(d, a, b, c, x[i + 13], 12, -40341101)
      c = ff(c, d, a, b, x[i + 14], 17, -1502002290)
      b = ff(b, c, d, a, x[i + 15], 22, 1236535329)
  
      a = gg(a, b, c, d, x[i + 1], 5, -165796510)
      d = gg(d, a, b, c, x[i + 6], 9, -1069501632)
      c = gg(c, d, a, b, x[i + 11], 14, 643717713)
      b = gg(b, c, d, a, x[i + 0], 20, -373897302)
      a = gg(a, b, c, d, x[i + 5], 5, -701558691)
      d = gg(d, a, b, c, x[i + 10], 9, 38016083)
      c = gg(c, d, a, b, x[i + 15], 14, -660478335)
      b = gg(b, c, d, a, x[i + 4], 20, -405537848)
      a = gg(a, b, c, d, x[i + 9], 5, 568446438)
      d = gg(d, a, b, c, x[i + 14], 9, -1019803690)
      c = gg(c, d, a, b, x[i + 3], 14, -187363961)
      b = gg(b, c, d, a, x[i + 8], 20, 1163531501)
      a = gg(a, b, c, d, x[i + 13], 5, -1444681467)
      d = gg(d, a, b, c, x[i + 2], 9, -51403784)
      c = gg(c, d, a, b, x[i + 7], 14, 1735328473)
      b = gg(b, c, d, a, x[i + 12], 20, -1926607734)
  
      a = hh(a, b, c, d, x[i + 5], 4, -378558)
      d = hh(d, a, b, c, x[i + 8], 11, -2022574463)
      c = hh(c, d, a, b, x[i + 11], 16, 1839030562)
      b = hh(b, c, d, a, x[i + 14], 23, -35309556)
      a = hh(a, b, c, d, x[i + 1], 4, -1530992060)
      d = hh(d, a, b, c, x[i + 4], 11, 1272893353)
      c = hh(c, d, a, b, x[i + 7], 16, -155497632)
      b = hh(b, c, d, a, x[i + 10], 23, -1094730640)
      a = hh(a, b, c, d, x[i + 13], 4, 681279174)
      d = hh(d, a, b, c, x[i + 0], 11, -358537222)
      c = hh(c, d, a, b, x[i + 3], 16, -722521979)
      b = hh(b, c, d, a, x[i + 6], 23, 76029189)
      a = hh(a, b, c, d, x[i + 9], 4, -640364487)
      d = hh(d, a, b, c, x[i + 12], 11, -421815835)
      c = hh(c, d, a, b, x[i + 15], 16, 530742520)
      b = hh(b, c, d, a, x[i + 2], 23, -995338651)
  
      a = ii(a, b, c, d, x[i + 0], 6, -198630844)
      d = ii(d, a, b, c, x[i + 7], 10, 1126891415)
      c = ii(c, d, a, b, x[i + 14], 15, -1416354905)
      b = ii(b, c, d, a, x[i + 5], 21, -57434055)
      a = ii(a, b, c, d, x[i + 12], 6, 1700485571)
      d = ii(d, a, b, c, x[i + 3], 10, -1894986606)
      c = ii(c, d, a, b, x[i + 10], 15, -1051523)
      b = ii(b, c, d, a, x[i + 1], 21, -2054922799)
      a = ii(a, b, c, d, x[i + 8], 6, 1873313359)
      d = ii(d, a, b, c, x[i + 15], 10, -30611744)
      c = ii(c, d, a, b, x[i + 6], 15, -1560198380)
      b = ii(b, c, d, a, x[i + 13], 21, 1309151649)
      a = ii(a, b, c, d, x[i + 4], 6, -145523070)
      d = ii(d, a, b, c, x[i + 11], 10, -1120210379)
      c = ii(c, d, a, b, x[i + 2], 15, 718787259)
      b = ii(b, c, d, a, x[i + 9], 21, -343485551)
  
      a = safe_add(a, olda)
      b = safe_add(b, oldb)
      c = safe_add(c, oldc)
      d = safe_add(d, oldd)
    }
    return [a, b, c, d]
  }
  
  /* 
   * Convert an array of little-endian words to a hex string. 
   */
  function binl2hex(binarray) {
    var hex_tab = "0123456789abcdef"
    var str = ""
    for (var i = 0; i < binarray.length * 4; i++) {
      str += hex_tab.charAt((binarray[i >> 2] >> ((i % 4) * 8 + 4)) & 0xF) +
        hex_tab.charAt((binarray[i >> 2] >> ((i % 4) * 8)) & 0xF)
    }
    return str
  }
  
  /* 
   * Convert an array of little-endian words to a base64 encoded string. 
   */
  function binl2b64(binarray) {
    var tab = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"
    var str = ""
    for (var i = 0; i < binarray.length * 32; i += 6) {
      str += tab.charAt(((binarray[i >> 5] << (i % 32)) & 0x3F) |
        ((binarray[i >> 5 + 1] >> (32 - i % 32)) & 0x3F))
    }
    return str
  }
  
  /* 
   * Convert an 8-bit character string to a sequence of 16-word blocks, stored 
   * as an array, and append appropriate padding for MD4/5 calculation. 
   * If any of the characters are >255, the high byte is silently ignored. 
   */
  function str2binl(str) {
    var nblk = ((str.length + 8) >> 6) + 1 // number of 16-word blocks  
    var blks = new Array(nblk * 16)
    for (var i = 0; i < nblk * 16; i++) blks[i] = 0
    for (var i = 0; i < str.length; i++)
      blks[i >> 2] |= (str.charCodeAt(i) & 0xFF) << ((i % 4) * 8)
    blks[i >> 2] |= 0x80 << ((i % 4) * 8)
    blks[nblk * 16 - 2] = str.length * 8
    return blks
  }
  
  /* 
   * Convert a wide-character string to a sequence of 16-word blocks, stored as 
   * an array, and append appropriate padding for MD4/5 calculation. 
   */
  function strw2binl(str) {
    var nblk = ((str.length + 4) >> 5) + 1 // number of 16-word blocks  
    var blks = new Array(nblk * 16)
    for (var i = 0; i < nblk * 16; i++) blks[i] = 0
    for (var i = 0; i < str.length; i++)
      blks[i >> 1] |= str.charCodeAt(i) << ((i % 2) * 16)
    blks[i >> 1] |= 0x80 << ((i % 2) * 16)
    blks[nblk * 16 - 2] = str.length * 16
    return blks
  }
  
  /* 
   * External interface 
   */
  function hexMD5(str) { return binl2hex(coreMD5(str2binl(str))) }
  function hexMD5w(str) { return binl2hex(coreMD5(strw2binl(str))) }
  function b64MD5(str) { return binl2b64(coreMD5(str2binl(str))) }
  function b64MD5w(str) { return binl2b64(coreMD5(strw2binl(str))) }
  /* Backward compatibility */
  function calcMD5(str) { return binl2hex(coreMD5(str2binl(str))) }
  module.exports = {
    hexMD5: hexMD5
  }  