Timestamp cracker, javascript

timestamp_cracker

//
// Cracker for Ingress timestamps.  YMMV.  BBIAB.  KK.
// See this page for example codes to test this with: https://gist.github.com/zeroaltitude/6213498
//
// Usage: main(<cipher> <hour> <trial number> <otp hash>)
//
// E.g.
//
// main('ISGDVWWJXCYSDRXDLSSOVOKIEUJNTVQLJSXQCLCYLRFEFYWVTZILMLACAKVTCCZJNOBYOJ', '2', '2', '7527D47FE0E8F422EE269B666C1A2CA2')
// !!!!!!!!!!! FOUND OTP/TIMESTAMP: WOGLBFSXTPFVKVJGDAVOCRRMQXVQRKCJZVSCIUFMDELLBGZVGWLGYRJJCNILPYCRJMNLLR/MEASUREMENTXTWOXISXATXTWOXOXCLOCKXFOURXMINUTESXANDXFOURTYXNINEXSECONDS
//
// main('SUZGNEKXBNORVSNVEACAVDHFYXZGDWPISLOVOXLAGESFLAMAN', '3', '3', '6b7ca401083b34628db954c1e8b1c5de')
// !!!!!!!!!!! FOUND OTP/TIMESTAMP: VBSPJANJEQMGHQDYQNYDJVULFTCGQTSDKGVXRSDFCHABJMZXV/XTHREEXOXXCLOCKXONEXMINUTEXANDXFIFTYXFIVEXSECONDS
// 
// Lots of performance work to still be done.  YMMV. 
//
// by zeroaltitude of the Boston Englightened
//

var BLOCK_PARSE_REGEX = /\$\{(\w+)\}/igm;
String.prototype.parse_vars = function(dataDict)
{
    return this.replace(BLOCK_PARSE_REGEX, function(match, param, offset, orig)
    {
        if (!dataDict) { return ""; }
        return (dataDict[param] || (dataDict[param] == 0)) ? (dataDict[param]) : ("");
    });
};

var WORDY_NUMBERS = {
    0: "zero",
    1: "one",
    2: "two",
    3: "three",
    4: "four",
    5: "five",
    6: "six",
    7: "seven",
    8: "eight",
    9: "nine"
};

var WORDY_TENS = {
    10: "ten",
    11: "eleven",
    12: "twelve",
    13: "thirteen",
    14: "fourteen",
    15: "fifteen",
    16: "sixteen",
    17: "seventeen",
    18: "eighteen",
    19: "nineteen",
    20: "twenty",
    30: "thirty",
    // USE FOR US:
    // 40: "forty",
    // USE FOR AUS:
    40: "fourty",
    50: "fifty"
};

var PADS = ["x"];

var SUFFIX = "";

var PREFIXES = [
    ""
];

var WPREFIXES = [
    "measurement ${one} is at "
];

var TIME_FORMAT_SELECTED = "";
var TIME_FORMATS = {
    'one': "${one}${two} minute${three} ${four} second${five} past ${six} o clock${seven}",
    'two': "${one}${two} o clock ${three} minute${four} and ${five} second${six}${seven}"
};


var MAX_PADDING = 2;  // 6
var MINUTES = 5;  // 5
var SECONDS = 60;  // 60


// only for numbers between [0 and 60)
function number_to_wordy_number(num)
{
    if (num < 10)
    {
        return WORDY_NUMBERS[num];
    }
    else if (num <= 20)
    {
        return WORDY_TENS[num];
    }
    else
    {
        if ((num % 10) === 0)
        {
            return WORDY_TENS[num];
        }
        else
        {
            var mod = num % 10;
            var base = num - mod;
            return WORDY_TENS[base] + " " + WORDY_NUMBERS[mod];
        }
    }
}

function generate_pads(pad, parts, parts_len, accum, depth, remaining, lambda)
{
    var start, part, end;
    // the minimum start value is more than zero if there are more remaining than we can fit
    // minus one to disclude the one we're in
    var remaining_depths = parts_len - depth;
    var overflow = remaining / MAX_PADDING;
    var modu = remaining - (remaining_depths * MAX_PADDING)
    // but also, if remaining_depths is zero, set start to remaining
    // console.log("precalc remaining: " + parts_len + '/' + remaining + '/' + depth + '/' + remaining_depths + '/' + overflow + '/' + modu);
    if (remaining_depths === 0)
    {
        start = remaining;
    }
    else
    {
        if (overflow > remaining_depths && modu != 0)
        {
            start = modu;
        }
        else
        {
            if (depth === 0)
            {
                start = 0;
            }
            else
            {
                start = 1;
            }
        }
    }
    // console.log('gpaccum: ' + depth + '/' + parts_len + '/' + accum + '/' + remaining);
    if (depth > parts_len)
    {
        // console.log('Testing ' + accum + '!');
        lambda(accum);
    }
    else
    {
        // end is the lesser of remaining and max padding:
        if (MAX_PADDING >= remaining)
        {
            // plus one because we're using range
            end = remaining + 1;
        }
        else
        {
            end = MAX_PADDING + 1;
        }
        // console.log('gplooping: ' + start + '/' + end + '/' + depth + '/' + parts_len + '/' + pad);
        for (var i = start; i < end; i++)
        {
            if (depth === parts_len)
            {
                part = '';
            }
            else
            {
                part = parts[depth];
            }
            var v = '';
            if (depth === 0) { v = 'TOP)'; } else { v = ''; }
            // console.log(v + 'calling gp: ' + '[[' + depth + ']]' + pad + '/' + parts + '/' + parts_len + '/' + accum + Array(i + 1).join(pad) + part + '/' + (depth + 1) + '/' + (remaining - i) + '(' + start + ')' + end + '-' + i);
            generate_pads(pad, parts, parts_len, accum + Array(i + 1).join(pad) + part, depth + 1, remaining - i, lambda);
        }
    }
}

function sequential_pads(basestr, lcipher, lambda)
{
    // if we can detect that the cipher length is not equal to the padded base string, we can
    // avoid making overhead calls
    var parts = basestr.split(' ');
    var parts_len = parts.length;
    var strlen = basestr.length - parts_len + 1;
    var ret = [];
    for (var i = 0, j = PADS.length; i < j; i++)
    {
        var pad = PADS[i];
        // console.log("calling generate pads");
        // console.log(pad, parts, parts_len, lcipher, strlen);
        generate_pads(pad, parts, parts_len, '', 0, lcipher - strlen, lambda);
    }
}

function plural_ending(num)
{
    if (num === 0 || num > 1)
    {
        return 's';
    }
    return '';
}

function get_prefixes(trial)
{
    var ret = [];
    for (prefix in PREFIXES)
    {
        // console.log("newprefix: " + PREFIXES[prefix]);
        ret.push(PREFIXES[prefix]);
    }
    for (prefix in WPREFIXES)
    {
        // console.log("newprefix_: " + WPREFIXES[prefix]);
        ret.push(WPREFIXES[prefix].parse_vars({'one': number_to_wordy_number(trial)}));
    }
    return ret;
}

// trial is "measurement 1" or 2 or whatever
function generate_timestamps(hour, trial, lcipher, lambda)
{
    // for every second between boundary hour:00:00 and boundary_hour:05:00, generate all the possible
    // timestamps
    var prefix;
    var ret = [];
    var prefixes = get_prefixes(trial);
    for (var ii = 0, jj = prefixes.length; ii < jj; ii++)
    {
        prefix = prefixes[ii];
        // console.log("prefix: " + prefix);
        //for (var minute = 4; minute < 5; minute++)
        for (var minute = 0; minute < MINUTES; minute++)
        {
            //for (var second = 49; second < 50; second++)
            for (var second = 0; second < SECONDS; second++)
            {
                // console.log("minute/second:");
                // console.log(minute + '/' + second);   
                var wsecond = number_to_wordy_number(second);
                var wminute = number_to_wordy_number(minute);
                var whour = number_to_wordy_number(hour);
                var ws_plural = plural_ending(second);
                var wm_plural = plural_ending(minute);
                var x, y;
                if (TIME_FORMAT_SELECTED === "one")
                {
                    x = sequential_pads(TIME_FORMATS['one'].parse_vars({'one': prefix, 'two': wminute, 'three': wm_plural, 'four': wsecond, 'five': ws_plural, 'six': whour, 'seven': SUFFIX}), lcipher, lambda);                    
                }
                else if (TIME_FORMAT_SELECTED == "two")
                {
                    y = sequential_pads(TIME_FORMATS['two'].parse_vars({'one': prefix, 'two': whour, 'three': wminute, 'four': wm_plural, 'five': wsecond, 'six': ws_plural, 'seven': SUFFIX}), lcipher, lambda);                    
                }
                else
                {
                    x = sequential_pads(TIME_FORMATS['one'].parse_vars({'one': prefix, 'two': wminute, 'three': wm_plural, 'four': wsecond, 'five': ws_plural, 'six': whour, 'seven': SUFFIX}), lcipher, lambda);
                    y = sequential_pads(TIME_FORMATS['two'].parse_vars({'one': prefix, 'two': whour, 'three': wminute, 'four': wm_plural, 'five': wsecond, 'six': ws_plural, 'seven': SUFFIX}), lcipher, lambda);
                }
                ret.push([x, y]);
            }
        }
    }
    return ret;
}

var PADARRAY = new Array((26 * 26) + 1);
var alphabet = ['A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z'];
function build_padmap()
{
    for (var x = 0, y = alphabet.length; x < y; x++)
    {
        var letter = alphabet[x];
        for (var xx = 0, yy = alphabet.length; xx < yy; xx++)
        {
            var xletter = alphabet[xx];
            var diff;
            var clear_int = letter.charCodeAt(0);
            var cipher_int = xletter.charCodeAt(0);
            if (cipher_int > clear_int)
            {
                diff = cipher_int - clear_int;
            }
            else if (cipher_int === clear_int)
            {
                diff = 0;
            }
            else
            {
                diff = 26 - (clear_int - cipher_int);
            }
            PADARRAY[(x * 26) + xx] = String.fromCharCode(65 + diff);
        }
    }
}

function generate_otp(timestamp, cipher, lcipher)
{
    // calculate the one time pad that rotates timestamp to cipher,
    // represented as all caps alpha, A=0, ... Z=25, etc
    var test_o = '';
    for (var index = 0; index < lcipher; index++)
    {
        test_o += PADARRAY[((timestamp.charCodeAt(index) - 65) * 26) + (cipher.charCodeAt(index) - 65)];
    }
    return test_o;
}

function check(timestamp, cipher, lcipher, target_hash, finish_function)
{
    var test_ts = timestamp.toUpperCase();
    //console.log(test_ts);   
    var otp = generate_otp(test_ts, cipher, lcipher);
    if (otp)
    {
        var otp_hash = hex_md5(otp);
        //if (test_ts === 'MEASUREMENTXTWOXISXATXTWOXOXCLOCKXFOURXMINUTESXANDXFOURTYXNINEXSECONDS')
        //{
        //    console.log("(test_ts)" + test_ts + ":(otp)" + otp + ":(target_hash)" + target_hash + ":(otp_hash)" + otp_hash.toUpperCase());
        //}
        if (target_hash === otp_hash.toUpperCase())
        {
            console.log("!!!!!!!!!!! FOUND OTP/TIMESTAMP: " + otp + " " + test_ts);
            console.log("Run solved at " + new Date());
            end = true;
            if (finish_function)
            {
                finish_function(test_ts);
            }
        }
    }
}

function main(cipher, hour, trial, target_hash, finish_function)
{
    console.log("Run began at " + new Date());
    console.log(cipher, hour, trial, target_hash);
    build_padmap();
    // Find the timestamp
    var lcipher = cipher.length;
    var target_hash = target_hash.toUpperCase();
    var end = false;
    generate_timestamps(hour, trial, lcipher, function(timestamp){check(timestamp, cipher, lcipher, target_hash, finish_function);});
    if (finish_function)
    {
        finish_function("search completed, none found");
    }
}

var TEST_CIPHER_1 = 'ISGDVWWJXCYSDRXDLSSOVOKIEUJNTVQLJSXQCLCYLRFEFYWVTZILMLACAKVTCCZJNOBYOJ';
var TEST_HASH_1 = '7527D47FE0E8F422EE269B666C1A2CA2';
var TEST_HOUR_1 = '2';
var TEST_TRIAL_2 = '2';

var TEST_CIPHER_2 = 'SUZGNEKXBNORVSNVEACAVDHFYXZGDWPISLOVOXLAGESFLAMAN';
var TEST_HASH_2 = '6b7ca401083b34628db954c1e8b1c5de';
var TEST_HOUR_2 = '3';
var TEST_TRIAL_3 = '3';

/////////////////////////////////////////// web
$(function() {
    $("body").on("click", "#go", function(event) {
        $("#answer").val("working...");
        console.log('run started');
        var cipher = $("#cipher").val();
        var hour = $("#hour").val();
        var trial = $("#trial").val();
        var target_hash = $("#otphash").val();
        MAX_PADDING = parseInt($("#depth").val());
        PREFIXES = [$("#prefix").val()];
        SUFFIX = $("#suffix").val();
        TIME_FORMAT_SELECTED = $("#format").val();
        main(cipher, hour, trial, target_hash, function(answer){if ($("#answer").val() === "working...") { $("#answer").val(answer); }});
    });
});

/////////////////////////////////////////// md5
/*
 * A JavaScript implementation of the RSA Data Security, Inc. MD5 Message
 * Digest Algorithm, as defined in RFC 1321.
 * Version 2.2 Copyright (C) Paul Johnston 1999 - 2009
 * Other contributors: Greg Holt, Andrew Kepert, Ydnar, Lostinet
 * Distributed under the BSD License
 * See http://pajhome.org.uk/crypt/md5 for more info.
 */

/*
 * Configurable variables. You may need to tweak these to be compatible with
 * the server-side, but the defaults work in most cases.
 */
var hexcase = 0;   /* hex output format. 0 - lowercase; 1 - uppercase        */
var b64pad  = "";  /* base-64 pad character. "=" for strict RFC compliance   */

/*
 * These are the functions you'll usually want to call
 * They take string arguments and return either hex or base-64 encoded strings
 */
function hex_md5(s)    { return rstr2hex(rstr_md5(str2rstr_utf8(s))); }
function b64_md5(s)    { return rstr2b64(rstr_md5(str2rstr_utf8(s))); }
function any_md5(s, e) { return rstr2any(rstr_md5(str2rstr_utf8(s)), e); }
function hex_hmac_md5(k, d)
  { return rstr2hex(rstr_hmac_md5(str2rstr_utf8(k), str2rstr_utf8(d))); }
function b64_hmac_md5(k, d)
  { return rstr2b64(rstr_hmac_md5(str2rstr_utf8(k), str2rstr_utf8(d))); }
function any_hmac_md5(k, d, e)
  { return rstr2any(rstr_hmac_md5(str2rstr_utf8(k), str2rstr_utf8(d)), e); }

/*
 * Perform a simple self-test to see if the VM is working
 */
function md5_vm_test()
{
  return hex_md5("abc").toLowerCase() == "900150983cd24fb0d6963f7d28e17f72";
}

/*
 * Calculate the MD5 of a raw string
 */
function rstr_md5(s)
{
  return binl2rstr(binl_md5(rstr2binl(s), s.length * 8));
}

/*
 * Calculate the HMAC-MD5, of a key and some data (raw strings)
 */
function rstr_hmac_md5(key, data)
{
  var bkey = rstr2binl(key);
  if(bkey.length > 16) bkey = binl_md5(bkey, key.length * 8);

  var ipad = Array(16), opad = Array(16);
  for(var i = 0; i < 16; i++)
  {
    ipad[i] = bkey[i] ^ 0x36363636;
    opad[i] = bkey[i] ^ 0x5C5C5C5C;
  }

  var hash = binl_md5(ipad.concat(rstr2binl(data)), 512 + data.length * 8);
  return binl2rstr(binl_md5(opad.concat(hash), 512 + 128));
}

/*
 * Convert a raw string to a hex string
 */
function rstr2hex(input)
{
  try { hexcase } catch(e) { hexcase=0; }
  var hex_tab = hexcase ? "0123456789ABCDEF" : "0123456789abcdef";
  var output = "";
  var x;
  for(var i = 0; i < input.length; i++)
  {
    x = input.charCodeAt(i);
    output += hex_tab.charAt((x >>> 4) & 0x0F)
           +  hex_tab.charAt( x        & 0x0F);
  }
  return output;
}

/*
 * Convert a raw string to a base-64 string
 */
function rstr2b64(input)
{
  try { b64pad } catch(e) { b64pad=''; }
  var tab = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
  var output = "";
  var len = input.length;
  for(var i = 0; i < len; i += 3)
  {
    var triplet = (input.charCodeAt(i) << 16)
                | (i + 1 < len ? input.charCodeAt(i+1) << 8 : 0)
                | (i + 2 < len ? input.charCodeAt(i+2)      : 0);
    for(var j = 0; j < 4; j++)
    {
      if(i * 8 + j * 6 > input.length * 8) output += b64pad;
      else output += tab.charAt((triplet >>> 6*(3-j)) & 0x3F);
    }
  }
  return output;
}

/*
 * Convert a raw string to an arbitrary string encoding
 */
function rstr2any(input, encoding)
{
  var divisor = encoding.length;
  var i, j, q, x, quotient;

  /* Convert to an array of 16-bit big-endian values, forming the dividend */
  var dividend = Array(Math.ceil(input.length / 2));
  for(i = 0; i < dividend.length; i++)
  {
    dividend[i] = (input.charCodeAt(i * 2) << 8) | input.charCodeAt(i * 2 + 1);
  }

  /*
   * Repeatedly perform a long division. The binary array forms the dividend,
   * the length of the encoding is the divisor. Once computed, the quotient
   * forms the dividend for the next step. All remainders are stored for later
   * use.
   */
  var full_length = Math.ceil(input.length * 8 /
                                    (Math.log(encoding.length) / Math.log(2)));
  var remainders = Array(full_length);
  for(j = 0; j < full_length; j++)
  {
    quotient = Array();
    x = 0;
    for(i = 0; i < dividend.length; i++)
    {
      x = (x << 16) + dividend[i];
      q = Math.floor(x / divisor);
      x -= q * divisor;
      if(quotient.length > 0 || q > 0)
        quotient[quotient.length] = q;
    }
    remainders[j] = x;
    dividend = quotient;
  }

  /* Convert the remainders to the output string */
  var output = "";
  for(i = remainders.length - 1; i >= 0; i--)
    output += encoding.charAt(remainders[i]);

  return output;
}

/*
 * Encode a string as utf-8.
 * For efficiency, this assumes the input is valid utf-16.
 */
function str2rstr_utf8(input)
{
  var output = "";
  var i = -1;
  var x, y;

  while(++i < input.length)
  {
    /* Decode utf-16 surrogate pairs */
    x = input.charCodeAt(i);
    y = i + 1 < input.length ? input.charCodeAt(i + 1) : 0;
    if(0xD800 <= x && x <= 0xDBFF && 0xDC00 <= y && y <= 0xDFFF)
    {
      x = 0x10000 + ((x & 0x03FF) << 10) + (y & 0x03FF);
      i++;
    }

    /* Encode output as utf-8 */
    if(x <= 0x7F)
      output += String.fromCharCode(x);
    else if(x <= 0x7FF)
      output += String.fromCharCode(0xC0 | ((x >>> 6 ) & 0x1F),
                                    0x80 | ( x         & 0x3F));
    else if(x <= 0xFFFF)
      output += String.fromCharCode(0xE0 | ((x >>> 12) & 0x0F),
                                    0x80 | ((x >>> 6 ) & 0x3F),
                                    0x80 | ( x         & 0x3F));
    else if(x <= 0x1FFFFF)
      output += String.fromCharCode(0xF0 | ((x >>> 18) & 0x07),
                                    0x80 | ((x >>> 12) & 0x3F),
                                    0x80 | ((x >>> 6 ) & 0x3F),
                                    0x80 | ( x         & 0x3F));
  }
  return output;
}

/*
 * Encode a string as utf-16
 */
function str2rstr_utf16le(input)
{
  var output = "";
  for(var i = 0; i < input.length; i++)
    output += String.fromCharCode( input.charCodeAt(i)        & 0xFF,
                                  (input.charCodeAt(i) >>> 8) & 0xFF);
  return output;
}

function str2rstr_utf16be(input)
{
  var output = "";
  for(var i = 0; i < input.length; i++)
    output += String.fromCharCode((input.charCodeAt(i) >>> 8) & 0xFF,
                                   input.charCodeAt(i)        & 0xFF);
  return output;
}

/*
 * Convert a raw string to an array of little-endian words
 * Characters >255 have their high-byte silently ignored.
 */
function rstr2binl(input)
{
  var output = Array(input.length >> 2);
  for(var i = 0; i < output.length; i++)
    output[i] = 0;
  for(var i = 0; i < input.length * 8; i += 8)
    output[i>>5] |= (input.charCodeAt(i / 8) & 0xFF) << (i%32);
  return output;
}

/*
 * Convert an array of little-endian words to a string
 */
function binl2rstr(input)
{
  var output = "";
  for(var i = 0; i < input.length * 32; i += 8)
    output += String.fromCharCode((input[i>>5] >>> (i % 32)) & 0xFF);
  return output;
}

/*
 * Calculate the MD5 of an array of little-endian words, and a bit length.
 */
function binl_md5(x, len)
{
  /* append padding */
  x[len >> 5] |= 0x80 << ((len) % 32);
  x[(((len + 64) >>> 9) << 4) + 14] = len;

  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 = md5_ff(a, b, c, d, x[i+ 0], 7 , -680876936);
    d = md5_ff(d, a, b, c, x[i+ 1], 12, -389564586);
    c = md5_ff(c, d, a, b, x[i+ 2], 17,  606105819);
    b = md5_ff(b, c, d, a, x[i+ 3], 22, -1044525330);
    a = md5_ff(a, b, c, d, x[i+ 4], 7 , -176418897);
    d = md5_ff(d, a, b, c, x[i+ 5], 12,  1200080426);
    c = md5_ff(c, d, a, b, x[i+ 6], 17, -1473231341);
    b = md5_ff(b, c, d, a, x[i+ 7], 22, -45705983);
    a = md5_ff(a, b, c, d, x[i+ 8], 7 ,  1770035416);
    d = md5_ff(d, a, b, c, x[i+ 9], 12, -1958414417);
    c = md5_ff(c, d, a, b, x[i+10], 17, -42063);
    b = md5_ff(b, c, d, a, x[i+11], 22, -1990404162);
    a = md5_ff(a, b, c, d, x[i+12], 7 ,  1804603682);
    d = md5_ff(d, a, b, c, x[i+13], 12, -40341101);
    c = md5_ff(c, d, a, b, x[i+14], 17, -1502002290);
    b = md5_ff(b, c, d, a, x[i+15], 22,  1236535329);

    a = md5_gg(a, b, c, d, x[i+ 1], 5 , -165796510);
    d = md5_gg(d, a, b, c, x[i+ 6], 9 , -1069501632);
    c = md5_gg(c, d, a, b, x[i+11], 14,  643717713);
    b = md5_gg(b, c, d, a, x[i+ 0], 20, -373897302);
    a = md5_gg(a, b, c, d, x[i+ 5], 5 , -701558691);
    d = md5_gg(d, a, b, c, x[i+10], 9 ,  38016083);
    c = md5_gg(c, d, a, b, x[i+15], 14, -660478335);
    b = md5_gg(b, c, d, a, x[i+ 4], 20, -405537848);
    a = md5_gg(a, b, c, d, x[i+ 9], 5 ,  568446438);
    d = md5_gg(d, a, b, c, x[i+14], 9 , -1019803690);
    c = md5_gg(c, d, a, b, x[i+ 3], 14, -187363961);
    b = md5_gg(b, c, d, a, x[i+ 8], 20,  1163531501);
    a = md5_gg(a, b, c, d, x[i+13], 5 , -1444681467);
    d = md5_gg(d, a, b, c, x[i+ 2], 9 , -51403784);
    c = md5_gg(c, d, a, b, x[i+ 7], 14,  1735328473);
    b = md5_gg(b, c, d, a, x[i+12], 20, -1926607734);

    a = md5_hh(a, b, c, d, x[i+ 5], 4 , -378558);
    d = md5_hh(d, a, b, c, x[i+ 8], 11, -2022574463);
    c = md5_hh(c, d, a, b, x[i+11], 16,  1839030562);
    b = md5_hh(b, c, d, a, x[i+14], 23, -35309556);
    a = md5_hh(a, b, c, d, x[i+ 1], 4 , -1530992060);
    d = md5_hh(d, a, b, c, x[i+ 4], 11,  1272893353);
    c = md5_hh(c, d, a, b, x[i+ 7], 16, -155497632);
    b = md5_hh(b, c, d, a, x[i+10], 23, -1094730640);
    a = md5_hh(a, b, c, d, x[i+13], 4 ,  681279174);
    d = md5_hh(d, a, b, c, x[i+ 0], 11, -358537222);
    c = md5_hh(c, d, a, b, x[i+ 3], 16, -722521979);
    b = md5_hh(b, c, d, a, x[i+ 6], 23,  76029189);
    a = md5_hh(a, b, c, d, x[i+ 9], 4 , -640364487);
    d = md5_hh(d, a, b, c, x[i+12], 11, -421815835);
    c = md5_hh(c, d, a, b, x[i+15], 16,  530742520);
    b = md5_hh(b, c, d, a, x[i+ 2], 23, -995338651);

    a = md5_ii(a, b, c, d, x[i+ 0], 6 , -198630844);
    d = md5_ii(d, a, b, c, x[i+ 7], 10,  1126891415);
    c = md5_ii(c, d, a, b, x[i+14], 15, -1416354905);
    b = md5_ii(b, c, d, a, x[i+ 5], 21, -57434055);
    a = md5_ii(a, b, c, d, x[i+12], 6 ,  1700485571);
    d = md5_ii(d, a, b, c, x[i+ 3], 10, -1894986606);
    c = md5_ii(c, d, a, b, x[i+10], 15, -1051523);
    b = md5_ii(b, c, d, a, x[i+ 1], 21, -2054922799);
    a = md5_ii(a, b, c, d, x[i+ 8], 6 ,  1873313359);
    d = md5_ii(d, a, b, c, x[i+15], 10, -30611744);
    c = md5_ii(c, d, a, b, x[i+ 6], 15, -1560198380);
    b = md5_ii(b, c, d, a, x[i+13], 21,  1309151649);
    a = md5_ii(a, b, c, d, x[i+ 4], 6 , -145523070);
    d = md5_ii(d, a, b, c, x[i+11], 10, -1120210379);
    c = md5_ii(c, d, a, b, x[i+ 2], 15,  718787259);
    b = md5_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];
}

/*
 * These functions implement the four basic operations the algorithm uses.
 */
function md5_cmn(q, a, b, x, s, t)
{
  return safe_add(bit_rol(safe_add(safe_add(a, q), safe_add(x, t)), s),b);
}
function md5_ff(a, b, c, d, x, s, t)
{
  return md5_cmn((b & c) | ((~b) & d), a, b, x, s, t);
}
function md5_gg(a, b, c, d, x, s, t)
{
  return md5_cmn((b & d) | (c & (~d)), a, b, x, s, t);
}
function md5_hh(a, b, c, d, x, s, t)
{
  return md5_cmn(b ^ c ^ d, a, b, x, s, t);
}
function md5_ii(a, b, c, d, x, s, t)
{
  return md5_cmn(c ^ (b | (~d)), a, b, x, s, t);
}

/*
 * 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 bit_rol(num, cnt)
{
  return (num << cnt) | (num >>> (32 - cnt));
}