/*
 * Hash class for JavaScript
 * Encapsulation by essoduke.org, August 2009
 * Modify: Tue, 11 August 2009 09:28:29 GMT
 *
 * usage:
 *  MD5:    hash.md5(string)
 *  SHA1:   hash.sha1(string)
 *  SHA256: hash.sha256(string)
 */
var hash = {
  /*
   * 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.
   */
  md5: function(s){
    return hash.md5_func.hex_md5(s);
  },
  
  md5_func: {
    /*
     * Configurable variables. You may need to tweak these to be compatible with
     * the server-side, but the defaults work in most cases.
     */
    hexcase: 0,   /* hex output format. 0 - lowercase; 1 - uppercase        */
    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
     */
    hex_md5: function(s) { return hash.md5_func.rstr2hex(hash.md5_func.rstr_md5(hash.md5_func.str2rstr_utf8(s))); },
    b64_md5: function(s) { return hash.md5_func.rstr2b64(hash.md5_func.rstr_md5(hash.md5_func.str2rstr_utf8(s))); },
    any_md5: function(s, e) { return hash.md5_func.rstr2any(hash.md5_func.rstr_md5(hash.md5_func.str2rstr_utf8(s)), e); },
    hex_hmac_md5: function(k, d) { return hash.md5_func.rstr2hex(hash.md5_func.rstr_hmac_md5(hash.md5_func.str2rstr_utf8(k), hash.md5_func.str2rstr_utf8(d))); },
    b64_hmac_md5: function(k, d) { return hash.md5_func.rstr2b64(hash.md5_func.rstr_hmac_md5(hash.md5_func.str2rstr_utf8(k), hash.md5_func.str2rstr_utf8(d))); },
    any_hmac_md5: function(k, d, e) { return hash.md5_func.rstr2any(hash.md5_func.rstr_hmac_md5(hash.md5_func.str2rstr_utf8(k), hash.md5_func.str2rstr_utf8(d)), e); },

    /*
     * Perform a simple self-test to see if the VM is working
     */
    md5_vm_test: function(){ return hash.md5_func.hex_md5("abc").toLowerCase() == "900150983cd24fb0d6963f7d28e17f72"; },

    /*
     * Calculate the MD5 of a raw string
     */
    rstr_md5: function(s){ return hash.md5_func.binl2rstr(hash.md5_func.binl_md5(hash.md5_func.rstr2binl(s), s.length * 8)); },

    /*
     * Calculate the HMAC-MD5, of a key and some data (raw strings)
     */
    rstr_hmac_md5: function(key, data){
      var bkey = hash.md5_func.rstr2binl(key);
      if(bkey.length > 16) bkey = hash.md5_func.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 = hash.md5_func.binl_md5(ipad.concat(hash.md5_func.rstr2binl(data)), 512 + data.length * 8);
      return hash.md5_func.binl2rstr(hash.md5_func.binl_md5(opad.concat(hash), 512 + 128));
    },

    /*
     * Convert a raw string to a hex string
     */
    rstr2hex: function(input){
      try { hash.md5_func.hexcase } catch(e) { hash.md5_func.hexcase=0; }
      var hex_tab = hash.md5_func.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
     */
    rstr2b64: function(input){
      try { hash.md5_func.b64pad } catch(e) { hash.md5_func.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 += hash.md5_func.b64pad;
          else output += tab.charAt((triplet >>> 6*(3-j)) & 0x3F);
        }
      }
      return output;
    },

    /*
     * Convert a raw string to an arbitrary string encoding
     */
    rstr2any: function(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.
     */
    str2rstr_utf8: function(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
     */
    str2rstr_utf16le: function(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;
    },

    str2rstr_utf16be: function(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.
     */
    rstr2binl: function(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
     */
    binl2rstr: function(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.
     */
    binl_md5: function(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 = hash.md5_func.md5_ff(a, b, c, d, x[i+ 0], 7 , -680876936);
        d = hash.md5_func.md5_ff(d, a, b, c, x[i+ 1], 12, -389564586);
        c = hash.md5_func.md5_ff(c, d, a, b, x[i+ 2], 17,  606105819);
        b = hash.md5_func.md5_ff(b, c, d, a, x[i+ 3], 22, -1044525330);
        a = hash.md5_func.md5_ff(a, b, c, d, x[i+ 4], 7 , -176418897);
        d = hash.md5_func.md5_ff(d, a, b, c, x[i+ 5], 12,  1200080426);
        c = hash.md5_func.md5_ff(c, d, a, b, x[i+ 6], 17, -1473231341);
        b = hash.md5_func.md5_ff(b, c, d, a, x[i+ 7], 22, -45705983);
        a = hash.md5_func.md5_ff(a, b, c, d, x[i+ 8], 7 ,  1770035416);
        d = hash.md5_func.md5_ff(d, a, b, c, x[i+ 9], 12, -1958414417);
        c = hash.md5_func.md5_ff(c, d, a, b, x[i+10], 17, -42063);
        b = hash.md5_func.md5_ff(b, c, d, a, x[i+11], 22, -1990404162);
        a = hash.md5_func.md5_ff(a, b, c, d, x[i+12], 7 ,  1804603682);
        d = hash.md5_func.md5_ff(d, a, b, c, x[i+13], 12, -40341101);
        c = hash.md5_func.md5_ff(c, d, a, b, x[i+14], 17, -1502002290);
        b = hash.md5_func.md5_ff(b, c, d, a, x[i+15], 22,  1236535329);

        a = hash.md5_func.md5_gg(a, b, c, d, x[i+ 1], 5 , -165796510);
        d = hash.md5_func.md5_gg(d, a, b, c, x[i+ 6], 9 , -1069501632);
        c = hash.md5_func.md5_gg(c, d, a, b, x[i+11], 14,  643717713);
        b = hash.md5_func.md5_gg(b, c, d, a, x[i+ 0], 20, -373897302);
        a = hash.md5_func.md5_gg(a, b, c, d, x[i+ 5], 5 , -701558691);
        d = hash.md5_func.md5_gg(d, a, b, c, x[i+10], 9 ,  38016083);
        c = hash.md5_func.md5_gg(c, d, a, b, x[i+15], 14, -660478335);
        b = hash.md5_func.md5_gg(b, c, d, a, x[i+ 4], 20, -405537848);
        a = hash.md5_func.md5_gg(a, b, c, d, x[i+ 9], 5 ,  568446438);
        d = hash.md5_func.md5_gg(d, a, b, c, x[i+14], 9 , -1019803690);
        c = hash.md5_func.md5_gg(c, d, a, b, x[i+ 3], 14, -187363961);
        b = hash.md5_func.md5_gg(b, c, d, a, x[i+ 8], 20,  1163531501);
        a = hash.md5_func.md5_gg(a, b, c, d, x[i+13], 5 , -1444681467);
        d = hash.md5_func.md5_gg(d, a, b, c, x[i+ 2], 9 , -51403784);
        c = hash.md5_func.md5_gg(c, d, a, b, x[i+ 7], 14,  1735328473);
        b = hash.md5_func.md5_gg(b, c, d, a, x[i+12], 20, -1926607734);

        a = hash.md5_func.md5_hh(a, b, c, d, x[i+ 5], 4 , -378558);
        d = hash.md5_func.md5_hh(d, a, b, c, x[i+ 8], 11, -2022574463);
        c = hash.md5_func.md5_hh(c, d, a, b, x[i+11], 16,  1839030562);
        b = hash.md5_func.md5_hh(b, c, d, a, x[i+14], 23, -35309556);
        a = hash.md5_func.md5_hh(a, b, c, d, x[i+ 1], 4 , -1530992060);
        d = hash.md5_func.md5_hh(d, a, b, c, x[i+ 4], 11,  1272893353);
        c = hash.md5_func.md5_hh(c, d, a, b, x[i+ 7], 16, -155497632);
        b = hash.md5_func.md5_hh(b, c, d, a, x[i+10], 23, -1094730640);
        a = hash.md5_func.md5_hh(a, b, c, d, x[i+13], 4 ,  681279174);
        d = hash.md5_func.md5_hh(d, a, b, c, x[i+ 0], 11, -358537222);
        c = hash.md5_func.md5_hh(c, d, a, b, x[i+ 3], 16, -722521979);
        b = hash.md5_func.md5_hh(b, c, d, a, x[i+ 6], 23,  76029189);
        a = hash.md5_func.md5_hh(a, b, c, d, x[i+ 9], 4 , -640364487);
        d = hash.md5_func.md5_hh(d, a, b, c, x[i+12], 11, -421815835);
        c = hash.md5_func.md5_hh(c, d, a, b, x[i+15], 16,  530742520);
        b = hash.md5_func.md5_hh(b, c, d, a, x[i+ 2], 23, -995338651);

        a = hash.md5_func.md5_ii(a, b, c, d, x[i+ 0], 6 , -198630844);
        d = hash.md5_func.md5_ii(d, a, b, c, x[i+ 7], 10,  1126891415);
        c = hash.md5_func.md5_ii(c, d, a, b, x[i+14], 15, -1416354905);
        b = hash.md5_func.md5_ii(b, c, d, a, x[i+ 5], 21, -57434055);
        a = hash.md5_func.md5_ii(a, b, c, d, x[i+12], 6 ,  1700485571);
        d = hash.md5_func.md5_ii(d, a, b, c, x[i+ 3], 10, -1894986606);
        c = hash.md5_func.md5_ii(c, d, a, b, x[i+10], 15, -1051523);
        b = hash.md5_func.md5_ii(b, c, d, a, x[i+ 1], 21, -2054922799);
        a = hash.md5_func.md5_ii(a, b, c, d, x[i+ 8], 6 ,  1873313359);
        d = hash.md5_func.md5_ii(d, a, b, c, x[i+15], 10, -30611744);
        c = hash.md5_func.md5_ii(c, d, a, b, x[i+ 6], 15, -1560198380);
        b = hash.md5_func.md5_ii(b, c, d, a, x[i+13], 21,  1309151649);
        a = hash.md5_func.md5_ii(a, b, c, d, x[i+ 4], 6 , -145523070);
        d = hash.md5_func.md5_ii(d, a, b, c, x[i+11], 10, -1120210379);
        c = hash.md5_func.md5_ii(c, d, a, b, x[i+ 2], 15,  718787259);
        b = hash.md5_func.md5_ii(b, c, d, a, x[i+ 9], 21, -343485551);

        a = hash.md5_func.safe_add(a, olda);
        b = hash.md5_func.safe_add(b, oldb);
        c = hash.md5_func.safe_add(c, oldc);
        d = hash.md5_func.safe_add(d, oldd);
      }
      return Array(a, b, c, d);
    },

    /*
     * These functions implement the four basic operations the algorithm uses.
     */
    md5_cmn: function(q, a, b, x, s, t){ return hash.md5_func.safe_add(hash.md5_func.bit_rol(hash.md5_func.safe_add(hash.md5_func.safe_add(a, q), hash.md5_func.safe_add(x, t)), s),b); },
    md5_ff: function(a, b, c, d, x, s, t){ return hash.md5_func.md5_cmn((b & c) | ((~b) & d), a, b, x, s, t); },
    md5_gg: function(a, b, c, d, x, s, t){ return hash.md5_func.md5_cmn((b & d) | (c & (~d)), a, b, x, s, t); },
    md5_hh: function(a, b, c, d, x, s, t){ return hash.md5_func.md5_cmn(b ^ c ^ d, a, b, x, s, t); },
    md5_ii: function(a, b, c, d, x, s, t){ return hash.md5_func.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.
     */
    safe_add: function(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.
     */
    bit_rol: function(num, cnt){ return (num << cnt) | (num >>> (32 - cnt)); }
  },

  /*
   * A JavaScript implementation of the Secure Hash Algorithm, SHA-1, as defined
   * in FIPS 180-1
   * Version 2.2 Copyright Paul Johnston 2000 - 2009.
   * Other contributors: Greg Holt, Andrew Kepert, Ydnar, Lostinet
   * Distributed under the BSD License
   * See http://pajhome.org.uk/crypt/md5 for details.
   */
  sha1: function(s){
    return hash.sha1_func.hex_sha1(s);
  },
  
  sha1_func: {
    /*
     * Configurable variables. You may need to tweak these to be compatible with
     * the server-side, but the defaults work in most cases.
     */
    hexcase: 0,  /* hex output format. 0 - lowercase; 1 - uppercase        */
    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
     */
    hex_sha1: function(s) { return hash.sha1_func.rstr2hex(hash.sha1_func.rstr_sha1(hash.sha1_func.str2rstr_utf8(s))); },
    b64_sha1: function(s) { return hash.sha1_func.rstr2b64(hash.sha1_func.rstr_sha1(hash.sha1_func.str2rstr_utf8(s))); },
    any_sha1: function(s, e) { return hash.sha1_func.rstr2any(hash.sha1_func.rstr_sha1(hash.sha1_func.str2rstr_utf8(s)), e); },
    hex_hmac_sha1: function(k, d) { return hash.sha1_func.rstr2hex(hash.sha1_func.rstr_hmac_sha1(hash.sha1_func.str2rstr_utf8(k), hash.sha1_func.str2rstr_utf8(d))); },
    b64_hmac_sha1: function(k, d) { return hash.sha1_func.rstr2b64(hash.sha1_func.rstr_hmac_sha1(hash.sha1_func.str2rstr_utf8(k), hash.sha1_func.str2rstr_utf8(d))); },
    any_hmac_sha1: function(k, d, e) { return hash.sha1_func.rstr2any(hash.sha1_func.rstr_hmac_sha1(hash.sha1_func.str2rstr_utf8(k), hash.sha1_func.str2rstr_utf8(d)), e); },

    /*
     * Perform a simple self-test to see if the VM is working
     */
    sha1_vm_test: function(){ return hash.sha1_func.hex_sha1("abc").toLowerCase() == "a9993e364706816aba3e25717850c26c9cd0d89d"; },

    /*
     * Calculate the SHA1 of a raw string
     */
    rstr_sha1: function(s) { return hash.sha1_func.binb2rstr(hash.sha1_func.binb_sha1(hash.sha1_func.rstr2binb(s), s.length * 8)); },

    /*
     * Calculate the HMAC-SHA1 of a key and some data (raw strings)
     */
    rstr_hmac_sha1: function(key, data){
      var bkey = hash.sha1_func.rstr2binb(key);
      if(bkey.length > 16) bkey = hash.sha1_func.binb_sha1(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 = hash.sha1_func.binb_sha1(ipad.concat(hash.sha1_func.rstr2binb(data)), 512 + data.length * 8);
      return hash.sha1_func.binb2rstr(hash.sha1_func.binb_sha1(opad.concat(hash), 512 + 160));
    },

    /*
     * Convert a raw string to a hex string
     */
    rstr2hex: function(input){
      try { hash.sha1_func.hexcase } catch(e) { hash.sha1_func.hexcase=0; }
      var hex_tab = hash.sha1_func.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
     */
    rstr2b64: function(input){
      try { hash.sha1_func.b64pad } catch(e) { hash.sha1_func.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 += hash.sha1_func.b64pad;
          else output += tab.charAt((triplet >>> 6*(3-j)) & 0x3F);
        }
      }
      return output;
    },

    /*
     * Convert a raw string to an arbitrary string encoding
     */
    rstr2any: function(input, encoding){
      var divisor = encoding.length;
      var remainders = Array();
      var i, 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. We stop when the dividend is zero.
       * All remainders are stored for later use.
       */
      while(dividend.length > 0){
        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[remainders.length] = 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]);
      }

      /* Append leading zero equivalents */
      var full_length = Math.ceil(input.length * 8 / (Math.log(encoding.length) / Math.log(2)))
      for(i = output.length; i < full_length; i++){
        output = encoding[0] + output;
      }
      return output;
    },

    /*
     * Encode a string as utf-8.
     * For efficiency, this assumes the input is valid utf-16.
     */
    str2rstr_utf8: function(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
     */
    str2rstr_utf16le: function(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;
    },

    str2rstr_utf16be: function(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 big-endian words
     * Characters >255 have their high-byte silently ignored.
     */
    rstr2binb: function(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) << (24 - i % 32);
      }
      return output;
    },

    /*
     * Convert an array of big-endian words to a string
     */
    binb2rstr: function(input){
      var output = "";
      for(var i = 0; i < input.length * 32; i += 8){
        output += String.fromCharCode((input[i>>5] >>> (24 - i % 32)) & 0xFF);
      }
      return output;
    },

    /*
     * Calculate the SHA-1 of an array of big-endian words, and a bit length
     */
    binb_sha1: function(x, len){
      /* append padding */
      x[len >> 5] |= 0x80 << (24 - len % 32);
      x[((len + 64 >> 9) << 4) + 15] = len;

      var w = Array(80);
      var a = 1732584193;
      var b = -271733879;
      var c = -1732584194;
      var d = 271733878;
      var e = -1009589776;

      for(var i = 0; i < x.length; i += 16){
        var olda = a;
        var oldb = b;
        var oldc = c;
        var oldd = d;
        var olde = e;

        for(var j = 0; j < 80; j++){
          if(j < 16) w[j] = x[i + j];
          else w[j] = hash.sha1_func.bit_rol(w[j-3] ^ w[j-8] ^ w[j-14] ^ w[j-16], 1);
          var t = hash.sha1_func.safe_add(hash.sha1_func.safe_add(hash.sha1_func.bit_rol(a, 5), hash.sha1_func.sha1_ft(j, b, c, d)), hash.sha1_func.safe_add(hash.sha1_func.safe_add(e, w[j]), hash.sha1_func.sha1_kt(j)));
          e = d;
          d = c;
          c = hash.sha1_func.bit_rol(b, 30);
          b = a;
          a = t;
        }

        a = hash.sha1_func.safe_add(a, olda);
        b = hash.sha1_func.safe_add(b, oldb);
        c = hash.sha1_func.safe_add(c, oldc);
        d = hash.sha1_func.safe_add(d, oldd);
        e = hash.sha1_func.safe_add(e, olde);
      }
      return Array(a, b, c, d, e);
    },

    /*
     * Perform the appropriate triplet combination function for the current
     * iteration
     */
    sha1_ft: function(t, b, c, d){
      if(t < 20) return (b & c) | ((~b) & d);
      if(t < 40) return b ^ c ^ d;
      if(t < 60) return (b & c) | (b & d) | (c & d);
      return b ^ c ^ d;
    },

    /*
     * Determine the appropriate additive constant for the current iteration
     */
    sha1_kt: function(t){
      return (t < 20) ?  1518500249 : (t < 40) ?  1859775393 : (t < 60) ? -1894007588 : -899497514;
    },

    /*
     * Add integers, wrapping at 2^32. This uses 16-bit operations internally
     * to work around bugs in some JS interpreters.
     */
    safe_add: function(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.
     */
    bit_rol: function(num, cnt){
      return (num << cnt) | (num >>> (32 - cnt));
    }
  },

  /*
   * A JavaScript implementation of the Secure Hash Algorithm, SHA-256, as defined
   * in FIPS 180-2
   * Version 2.2 Copyright Angel Marin, Paul Johnston 2000 - 2009.
   * Other contributors: Greg Holt, Andrew Kepert, Ydnar, Lostinet
   * Distributed under the BSD License
   * See http://pajhome.org.uk/crypt/md5 for details.
   * Also http://anmar.eu.org/projects/jssha2/
   */
  sha256: function(s){
    return hash.sha256_func.hex_sha256(s);
  },
 
  sha256_func: {
    /*
     * Configurable variables. You may need to tweak these to be compatible with
     * the server-side, but the defaults work in most cases.
     */
    hexcase: 0,  /* hex output format. 0 - lowercase; 1 - uppercase        */
    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
     */
    hex_sha256: function(s){ return hash.sha256_func.rstr2hex(hash.sha256_func.rstr_sha256(hash.sha256_func.str2rstr_utf8(s))); },
    b64_sha256: function(s){ return hash.sha256_func.rstr2b64(hash.sha256_func.rstr_sha256(hash.sha256_func.str2rstr_utf8(s))); },
    any_sha256: function(s, e){ return hash.sha256_func.rstr2any(hash.sha256_func.rstr_sha256(hash.sha256_func.str2rstr_utf8(s)), e); },
    hex_hmac_sha256: function(k, d){ return hash.sha256_func.rstr2hex(hash.sha256_func.rstr_hmac_sha256(hash.sha256_func.str2rstr_utf8(k), hash.sha256_func.str2rstr_utf8(d))); },
    b64_hmac_sha256: function(k, d){ return hash.sha256_func.rstr2b64(hash.sha256_func.rstr_hmac_sha256(hash.sha256_func.str2rstr_utf8(k), hash.sha256_func.str2rstr_utf8(d))); },
    any_hmac_sha256: function(k, d, e){ return hash.sha256_func.rstr2any(hash.sha256_func.rstr_hmac_sha256(hash.sha256_func.str2rstr_utf8(k), hash.sha256_func.str2rstr_utf8(d)), e); },

    /*
     * Perform a simple self-test to see if the VM is working
     */
    sha256_vm_test: function(){ return hash.sha256_func.hex_sha256("abc").toLowerCase() == "ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad"; },

    /*
     * Calculate the sha256 of a raw string
     */
    rstr_sha256: function(s){ return hash.sha256_func.binb2rstr(hash.sha256_func.binb_sha256(hash.sha256_func.rstr2binb(s), s.length * 8)); },

    /*
     * Calculate the HMAC-sha256 of a key and some data (raw strings)
     */
    rstr_hmac_sha256: function(key, data){
      var bkey = hash.sha256_func.rstr2binb(key);
      if(bkey.length > 16) bkey = hash.sha256_func.binb_sha256(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 = hash.sha256_func.binb_sha256(ipad.concat(hash.sha256_func.rstr2binb(data)), 512 + data.length * 8);
      return hash.sha256_func.binb2rstr(hash.sha256_func.binb_sha256(opad.concat(hash), 512 + 256));
    },

    /*
     * Convert a raw string to a hex string
     */
    rstr2hex: function(input){
      try { hash.sha256_func.hexcase } catch(e) { hash.sha256_func.hexcase=0; }
      var hex_tab = hash.sha256_func.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
     */
    rstr2b64: function(input){
      try { hash.sha256_func.b64pad } catch(e) { hash.sha256_func.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 += hash.sha256_func.b64pad;
          else output += tab.charAt((triplet >>> 6*(3-j)) & 0x3F);
        }
      }
      return output;
    },

    /*
     * Convert a raw string to an arbitrary string encoding
     */
    rstr2any: function(input, encoding){
      var divisor = encoding.length;
      var remainders = Array();
      var i, 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. We stop when the dividend is zero.
       * All remainders are stored for later use.
       */
      while(dividend.length > 0){
        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[remainders.length] = 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]);
      }

      /* Append leading zero equivalents */
      var full_length = Math.ceil(input.length * 8 / (Math.log(encoding.length) / Math.log(2)))
      for(i = output.length; i < full_length; i++){
        output = encoding[0] + output;
      }
      return output;
    },

    /*
     * Encode a string as utf-8.
     * For efficiency, this assumes the input is valid utf-16.
     */
    str2rstr_utf8: function(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
     */
    str2rstr_utf16le: function(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;
    },

    str2rstr_utf16be: function(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 big-endian words
     * Characters >255 have their high-byte silently ignored.
     */
    rstr2binb: function(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) << (24 - i % 32);
      }
      return output;
    },

    /*
     * Convert an array of big-endian words to a string
     */
    binb2rstr: function(input){
      var output = "";
      for(var i = 0; i < input.length * 32; i += 8){
        output += String.fromCharCode((input[i>>5] >>> (24 - i % 32)) & 0xFF);
      }
      return output;
    },

    /*
     * Main sha256 function, with its support functions
     */
    sha256_S: function(X, n) {return ( X >>> n ) | (X << (32 - n));},
    sha256_R: function(X, n) {return ( X >>> n );},
    sha256_Ch: function(x, y, z) {return ((x & y) ^ ((~x) & z));},
    sha256_Maj: function(x, y, z) {return ((x & y) ^ (x & z) ^ (y & z));},
    sha256_Sigma0256: function(x) {return (hash.sha256_func.sha256_S(x, 2) ^ hash.sha256_func.sha256_S(x, 13) ^ hash.sha256_func.sha256_S(x, 22));},
    sha256_Sigma1256: function(x) {return (hash.sha256_func.sha256_S(x, 6) ^ hash.sha256_func.sha256_S(x, 11) ^ hash.sha256_func.sha256_S(x, 25));},
    sha256_Gamma0256: function(x) {return (hash.sha256_func.sha256_S(x, 7) ^ hash.sha256_func.sha256_S(x, 18) ^ hash.sha256_func.sha256_R(x, 3));},
    sha256_Gamma1256: function(x) {return (hash.sha256_func.sha256_S(x, 17) ^ hash.sha256_func.sha256_S(x, 19) ^ hash.sha256_func.sha256_R(x, 10));},
    sha256_Sigma0512: function(x) {return (hash.sha256_func.sha256_S(x, 28) ^ hash.sha256_func.sha256_S(x, 34) ^ hash.sha256_func.sha256_S(x, 39));},
    sha256_Sigma1512: function(x) {return (hash.sha256_func.sha256_S(x, 14) ^ hash.sha256_func.sha256_S(x, 18) ^ hash.sha256_func.sha256_S(x, 41));},
    sha256_Gamma0512: function(x) {return (hash.sha256_func.sha256_S(x, 1)  ^ hash.sha256_func.sha256_S(x, 8) ^ hash.sha256_func.sha256_R(x, 7));},
    sha256_Gamma1512: function(x) {return (hash.sha256_func.sha256_S(x, 19) ^ hash.sha256_func.sha256_S(x, 61) ^ hash.sha256_func.sha256_R(x, 6));},

    sha256_K: new Array
    (
      1116352408, 1899447441, -1245643825, -373957723, 961987163, 1508970993,
      -1841331548, -1424204075, -670586216, 310598401, 607225278, 1426881987,
      1925078388, -2132889090, -1680079193, -1046744716, -459576895, -272742522,
      264347078, 604807628, 770255983, 1249150122, 1555081692, 1996064986,
      -1740746414, -1473132947, -1341970488, -1084653625, -958395405, -710438585,
      113926993, 338241895, 666307205, 773529912, 1294757372, 1396182291,
      1695183700, 1986661051, -2117940946, -1838011259, -1564481375, -1474664885,
      -1035236496, -949202525, -778901479, -694614492, -200395387, 275423344,
      430227734, 506948616, 659060556, 883997877, 958139571, 1322822218,
      1537002063, 1747873779, 1955562222, 2024104815, -2067236844, -1933114872,
      -1866530822, -1538233109, -1090935817, -965641998
    ),

    binb_sha256: function(m, l){
      var HASH = new Array(1779033703, -1150833019, 1013904242, -1521486534, 1359893119, -1694144372, 528734635, 1541459225);
      var W = new Array(64);
      var a, b, c, d, e, f, g, h;
      var i, j, T1, T2;

      /* append padding */
      m[l >> 5] |= 0x80 << (24 - l % 32);
      m[((l + 64 >> 9) << 4) + 15] = l;

      for(i = 0; i < m.length; i += 16){
        a = HASH[0];
        b = HASH[1];
        c = HASH[2];
        d = HASH[3];
        e = HASH[4];
        f = HASH[5];
        g = HASH[6];
        h = HASH[7];

        for(j = 0; j < 64; j++){
          if (j < 16) W[j] = m[j + i];
          else W[j] = hash.sha256_func.safe_add(hash.sha256_func.safe_add(hash.sha256_func.safe_add(hash.sha256_func.sha256_Gamma1256(W[j - 2]), W[j - 7]), hash.sha256_func.sha256_Gamma0256(W[j - 15])), W[j - 16]);

          T1 = hash.sha256_func.safe_add(hash.sha256_func.safe_add(hash.sha256_func.safe_add(hash.sha256_func.safe_add(h, hash.sha256_func.sha256_Sigma1256(e)), hash.sha256_func.sha256_Ch(e, f, g)), hash.sha256_func.sha256_K[j]), W[j]);
          T2 = hash.sha256_func.safe_add(hash.sha256_func.sha256_Sigma0256(a), hash.sha256_func.sha256_Maj(a, b, c));
          h = g;
          g = f;
          f = e;
          e = hash.sha256_func.safe_add(d, T1);
          d = c;
          c = b;
          b = a;
          a = hash.sha256_func.safe_add(T1, T2);
        }

        HASH[0] = hash.sha256_func.safe_add(a, HASH[0]);
        HASH[1] = hash.sha256_func.safe_add(b, HASH[1]);
        HASH[2] = hash.sha256_func.safe_add(c, HASH[2]);
        HASH[3] = hash.sha256_func.safe_add(d, HASH[3]);
        HASH[4] = hash.sha256_func.safe_add(e, HASH[4]);
        HASH[5] = hash.sha256_func.safe_add(f, HASH[5]);
        HASH[6] = hash.sha256_func.safe_add(g, HASH[6]);
        HASH[7] = hash.sha256_func.safe_add(h, HASH[7]);
      }
      return HASH;
    },

    safe_add: function(x, y){
      var lsw = (x & 0xFFFF) + (y & 0xFFFF);
      var msw = (x >> 16) + (y >> 16) + (lsw >> 16);
      return (msw << 16) | (lsw & 0xFFFF);
    }
  }
};