text: /* -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
  /* vim: set shiftwidth=2 tabstop=2 autoindent cindent expandtab: */
  /* Copyright 2012 Mozilla Foundation
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  /* globals bytesToString, DecryptStream, error, isInt, isName, Name,
             PasswordException, PasswordResponses, stringToBytes */
  
  'use strict';
  
  var ARCFourCipher = (function ARCFourCipherClosure() {
    function ARCFourCipher(key) {
      this.a = 0;
      this.b = 0;
      var s = new Uint8Array(256);
      var i, j = 0, tmp, keyLength = key.length;
      for (i = 0; i < 256; ++i)
        s[i] = i;
      for (i = 0; i < 256; ++i) {
        tmp = s[i];
        j = (j + tmp + key[i % keyLength]) & 0xFF;
        s[i] = s[j];
        s[j] = tmp;
      }
      this.s = s;
    }
  
    ARCFourCipher.prototype = {
      encryptBlock: function ARCFourCipher_encryptBlock(data) {
        var i, n = data.length, tmp, tmp2;
        var a = this.a, b = this.b, s = this.s;
        var output = new Uint8Array(n);
        for (i = 0; i < n; ++i) {
          a = (a + 1) & 0xFF;
          tmp = s[a];
          b = (b + tmp) & 0xFF;
          tmp2 = s[b];
          s[a] = tmp2;
          s[b] = tmp;
          output[i] = data[i] ^ s[(tmp + tmp2) & 0xFF];
        }
        this.a = a;
        this.b = b;
        return output;
      }
    };
    ARCFourCipher.prototype.decryptBlock = ARCFourCipher.prototype.encryptBlock;
  
    return ARCFourCipher;
  })();
  
  var calculateMD5 = (function calculateMD5Closure() {
    var r = new Uint8Array([
      7, 12, 17, 22, 7, 12, 17, 22, 7, 12, 17, 22, 7, 12, 17, 22,
      5, 9, 14, 20, 5, 9, 14, 20, 5, 9, 14, 20, 5, 9, 14, 20,
      4, 11, 16, 23, 4, 11, 16, 23, 4, 11, 16, 23, 4, 11, 16, 23,
      6, 10, 15, 21, 6, 10, 15, 21, 6, 10, 15, 21, 6, 10, 15, 21]);
  
    var k = new Int32Array([
      -680876936, -389564586, 606105819, -1044525330, -176418897, 1200080426,
      -1473231341, -45705983, 1770035416, -1958414417, -42063, -1990404162,
      1804603682, -40341101, -1502002290, 1236535329, -165796510, -1069501632,
      643717713, -373897302, -701558691, 38016083, -660478335, -405537848,
      568446438, -1019803690, -187363961, 1163531501, -1444681467, -51403784,
      1735328473, -1926607734, -378558, -2022574463, 1839030562, -35309556,
      -1530992060, 1272893353, -155497632, -1094730640, 681279174, -358537222,
      -722521979, 76029189, -640364487, -421815835, 530742520, -995338651,
      -198630844, 1126891415, -1416354905, -57434055, 1700485571, -1894986606,
      -1051523, -2054922799, 1873313359, -30611744, -1560198380, 1309151649,
      -145523070, -1120210379, 718787259, -343485551]);
  
    function hash(data, offset, length) {
      var h0 = 1732584193, h1 = -271733879, h2 = -1732584194, h3 = 271733878;
      // pre-processing
      var paddedLength = (length + 72) & ~63; // data + 9 extra bytes
      var padded = new Uint8Array(paddedLength);
      var i, j, n;
      for (i = 0; i < length; ++i)
        padded[i] = data[offset++];
      padded[i++] = 0x80;
      n = paddedLength - 8;
      while (i < n)
        padded[i++] = 0;
      padded[i++] = (length << 3) & 0xFF;
      padded[i++] = (length >> 5) & 0xFF;
      padded[i++] = (length >> 13) & 0xFF;
      padded[i++] = (length >> 21) & 0xFF;
      padded[i++] = (length >>> 29) & 0xFF;
      padded[i++] = 0;
      padded[i++] = 0;
      padded[i++] = 0;
      // chunking
      // TODO ArrayBuffer ?
      var w = new Int32Array(16);
      for (i = 0; i < paddedLength;) {
        for (j = 0; j < 16; ++j, i += 4) {
          w[j] = (padded[i] | (padded[i + 1] << 8) |
                  (padded[i + 2] << 16) | (padded[i + 3] << 24));
        }
        var a = h0, b = h1, c = h2, d = h3, f, g;
        for (j = 0; j < 64; ++j) {
          if (j < 16) {
            f = (b & c) | ((~b) & d);
            g = j;
          } else if (j < 32) {
            f = (d & b) | ((~d) & c);
            g = (5 * j + 1) & 15;
          } else if (j < 48) {
            f = b ^ c ^ d;
            g = (3 * j + 5) & 15;
          } else {
            f = c ^ (b | (~d));
            g = (7 * j) & 15;
          }
          var tmp = d, rotateArg = (a + f + k[j] + w[g]) | 0, rotate = r[j];
          d = c;
          c = b;
          b = (b + ((rotateArg << rotate) | (rotateArg >>> (32 - rotate)))) | 0;
          a = tmp;
        }
        h0 = (h0 + a) | 0;
        h1 = (h1 + b) | 0;
        h2 = (h2 + c) | 0;
        h3 = (h3 + d) | 0;
      }
      return new Uint8Array([
          h0 & 0xFF, (h0 >> 8) & 0xFF, (h0 >> 16) & 0xFF, (h0 >>> 24) & 0xFF,
          h1 & 0xFF, (h1 >> 8) & 0xFF, (h1 >> 16) & 0xFF, (h1 >>> 24) & 0xFF,
          h2 & 0xFF, (h2 >> 8) & 0xFF, (h2 >> 16) & 0xFF, (h2 >>> 24) & 0xFF,
          h3 & 0xFF, (h3 >> 8) & 0xFF, (h3 >> 16) & 0xFF, (h3 >>> 24) & 0xFF
      ]);
    }
    return hash;
  })();
  
  var NullCipher = (function NullCipherClosure() {
    function NullCipher() {
    }
  
    NullCipher.prototype = {
      decryptBlock: function NullCipher_decryptBlock(data) {
        return data;
      }
    };
  
    return NullCipher;
  })();
  
  var AES128Cipher = (function AES128CipherClosure() {
    var rcon = new Uint8Array([
      0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c,
      0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a,
      0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd,
      0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a,
      0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80,
      0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6,
      0x97, 0x35, 0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39, 0x72,
      0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc,
      0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02, 0x04, 0x08, 0x10,
      0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e,
      0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5,
      0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94,
      0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb, 0x8d, 0x01, 0x02,
      0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c, 0xd8, 0xab, 0x4d,
      0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a, 0xd4, 0xb3, 0x7d,
      0xfa, 0xef, 0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd, 0x61, 0xc2, 0x9f,
      0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a, 0x74, 0xe8, 0xcb,
      0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36, 0x6c,
      0xd8, 0xab, 0x4d, 0x9a, 0x2f, 0x5e, 0xbc, 0x63, 0xc6, 0x97, 0x35, 0x6a,
      0xd4, 0xb3, 0x7d, 0xfa, 0xef, 0xc5, 0x91, 0x39, 0x72, 0xe4, 0xd3, 0xbd,
      0x61, 0xc2, 0x9f, 0x25, 0x4a, 0x94, 0x33, 0x66, 0xcc, 0x83, 0x1d, 0x3a,
      0x74, 0xe8, 0xcb, 0x8d]);
  
    var s = new Uint8Array([
      0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5, 0x30, 0x01, 0x67, 0x2b,
      0xfe, 0xd7, 0xab, 0x76, 0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0,
      0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0, 0xb7, 0xfd, 0x93, 0x26,
      0x36, 0x3f, 0xf7, 0xcc, 0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15,
      0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a, 0x07, 0x12, 0x80, 0xe2,
      0xeb, 0x27, 0xb2, 0x75, 0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0,
      0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84, 0x53, 0xd1, 0x00, 0xed,
      0x20, 0xfc, 0xb1, 0x5b, 0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf,
      0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85, 0x45, 0xf9, 0x02, 0x7f,
      0x50, 0x3c, 0x9f, 0xa8, 0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5,
      0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2, 0xcd, 0x0c, 0x13, 0xec,
      0x5f, 0x97, 0x44, 0x17, 0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73,
      0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88, 0x46, 0xee, 0xb8, 0x14,
      0xde, 0x5e, 0x0b, 0xdb, 0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c,
      0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79, 0xe7, 0xc8, 0x37, 0x6d,
      0x8d, 0xd5, 0x4e, 0xa9, 0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08,
      0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6, 0xe8, 0xdd, 0x74, 0x1f,
      0x4b, 0xbd, 0x8b, 0x8a, 0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e,
      0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e, 0xe1, 0xf8, 0x98, 0x11,
      0x69, 0xd9, 0x8e, 0x94, 0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf,
      0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68, 0x41, 0x99, 0x2d, 0x0f,
      0xb0, 0x54, 0xbb, 0x16]);
  
    var inv_s = new Uint8Array([
      0x52, 0x09, 0x6a, 0xd5, 0x30, 0x36, 0xa5, 0x38, 0xbf, 0x40, 0xa3, 0x9e,
      0x81, 0xf3, 0xd7, 0xfb, 0x7c, 0xe3, 0x39, 0x82, 0x9b, 0x2f, 0xff, 0x87,
      0x34, 0x8e, 0x43, 0x44, 0xc4, 0xde, 0xe9, 0xcb, 0x54, 0x7b, 0x94, 0x32,
      0xa6, 0xc2, 0x23, 0x3d, 0xee, 0x4c, 0x95, 0x0b, 0x42, 0xfa, 0xc3, 0x4e,
      0x08, 0x2e, 0xa1, 0x66, 0x28, 0xd9, 0x24, 0xb2, 0x76, 0x5b, 0xa2, 0x49,
      0x6d, 0x8b, 0xd1, 0x25, 0x72, 0xf8, 0xf6, 0x64, 0x86, 0x68, 0x98, 0x16,
      0xd4, 0xa4, 0x5c, 0xcc, 0x5d, 0x65, 0xb6, 0x92, 0x6c, 0x70, 0x48, 0x50,
      0xfd, 0xed, 0xb9, 0xda, 0x5e, 0x15, 0x46, 0x57, 0xa7, 0x8d, 0x9d, 0x84,
      0x90, 0xd8, 0xab, 0x00, 0x8c, 0xbc, 0xd3, 0x0a, 0xf7, 0xe4, 0x58, 0x05,
      0xb8, 0xb3, 0x45, 0x06, 0xd0, 0x2c, 0x1e, 0x8f, 0xca, 0x3f, 0x0f, 0x02,
      0xc1, 0xaf, 0xbd, 0x03, 0x01, 0x13, 0x8a, 0x6b, 0x3a, 0x91, 0x11, 0x41,
      0x4f, 0x67, 0xdc, 0xea, 0x97, 0xf2, 0xcf, 0xce, 0xf0, 0xb4, 0xe6, 0x73,
      0x96, 0xac, 0x74, 0x22, 0xe7, 0xad, 0x35, 0x85, 0xe2, 0xf9, 0x37, 0xe8,
      0x1c, 0x75, 0xdf, 0x6e, 0x47, 0xf1, 0x1a, 0x71, 0x1d, 0x29, 0xc5, 0x89,
      0x6f, 0xb7, 0x62, 0x0e, 0xaa, 0x18, 0xbe, 0x1b, 0xfc, 0x56, 0x3e, 0x4b,
      0xc6, 0xd2, 0x79, 0x20, 0x9a, 0xdb, 0xc0, 0xfe, 0x78, 0xcd, 0x5a, 0xf4,
      0x1f, 0xdd, 0xa8, 0x33, 0x88, 0x07, 0xc7, 0x31, 0xb1, 0x12, 0x10, 0x59,
      0x27, 0x80, 0xec, 0x5f, 0x60, 0x51, 0x7f, 0xa9, 0x19, 0xb5, 0x4a, 0x0d,
      0x2d, 0xe5, 0x7a, 0x9f, 0x93, 0xc9, 0x9c, 0xef, 0xa0, 0xe0, 0x3b, 0x4d,
      0xae, 0x2a, 0xf5, 0xb0, 0xc8, 0xeb, 0xbb, 0x3c, 0x83, 0x53, 0x99, 0x61,
      0x17, 0x2b, 0x04, 0x7e, 0xba, 0x77, 0xd6, 0x26, 0xe1, 0x69, 0x14, 0x63,
      0x55, 0x21, 0x0c, 0x7d]);
  
    var mix = new Uint32Array([
      0x00000000, 0x0e090d0b, 0x1c121a16, 0x121b171d, 0x3824342c, 0x362d3927,
      0x24362e3a, 0x2a3f2331, 0x70486858, 0x7e416553, 0x6c5a724e, 0x62537f45,
      0x486c5c74, 0x4665517f, 0x547e4662, 0x5a774b69, 0xe090d0b0, 0xee99ddbb,
      0xfc82caa6, 0xf28bc7ad, 0xd8b4e49c, 0xd6bde997, 0xc4a6fe8a, 0xcaaff381,
      0x90d8b8e8, 0x9ed1b5e3, 0x8ccaa2fe, 0x82c3aff5, 0xa8fc8cc4, 0xa6f581cf,
      0xb4ee96d2, 0xbae79bd9, 0xdb3bbb7b, 0xd532b670, 0xc729a16d, 0xc920ac66,
      0xe31f8f57, 0xed16825c, 0xff0d9541, 0xf104984a, 0xab73d323, 0xa57ade28,
      0xb761c935, 0xb968c43e, 0x9357e70f, 0x9d5eea04, 0x8f45fd19, 0x814cf012,
      0x3bab6bcb, 0x35a266c0, 0x27b971dd, 0x29b07cd6, 0x038f5fe7, 0x0d8652ec,
      0x1f9d45f1, 0x119448fa, 0x4be30393, 0x45ea0e98, 0x57f11985, 0x59f8148e,
      0x73c737bf, 0x7dce3ab4, 0x6fd52da9, 0x61dc20a2, 0xad766df6, 0xa37f60fd,
      0xb16477e0, 0xbf6d7aeb, 0x955259da, 0x9b5b54d1, 0x894043cc, 0x87494ec7,
      0xdd3e05ae, 0xd33708a5, 0xc12c1fb8, 0xcf2512b3, 0xe51a3182, 0xeb133c89,
      0xf9082b94, 0xf701269f, 0x4de6bd46, 0x43efb04d, 0x51f4a750, 0x5ffdaa5b,
      0x75c2896a, 0x7bcb8461, 0x69d0937c, 0x67d99e77, 0x3daed51e, 0x33a7d815,
      0x21bccf08, 0x2fb5c203, 0x058ae132, 0x0b83ec39, 0x1998fb24, 0x1791f62f,
      0x764dd68d, 0x7844db86, 0x6a5fcc9b, 0x6456c190, 0x4e69e2a1, 0x4060efaa,
      0x527bf8b7, 0x5c72f5bc, 0x0605bed5, 0x080cb3de, 0x1a17a4c3, 0x141ea9c8,
      0x3e218af9, 0x302887f2, 0x223390ef, 0x2c3a9de4, 0x96dd063d, 0x98d40b36,
      0x8acf1c2b, 0x84c61120, 0xaef93211, 0xa0f03f1a, 0xb2eb2807, 0xbce2250c,
      0xe6956e65, 0xe89c636e, 0xfa877473, 0xf48e7978, 0xdeb15a49, 0xd0b85742,
      0xc2a3405f, 0xccaa4d54, 0x41ecdaf7, 0x4fe5d7fc, 0x5dfec0e1, 0x53f7cdea,
      0x79c8eedb, 0x77c1e3d0, 0x65daf4cd, 0x6bd3f9c6, 0x31a4b2af, 0x3fadbfa4,
      0x2db6a8b9, 0x23bfa5b2, 0x09808683, 0x07898b88, 0x15929c95, 0x1b9b919e,
      0xa17c0a47, 0xaf75074c, 0xbd6e1051, 0xb3671d5a, 0x99583e6b, 0x97513360,
      0x854a247d, 0x8b432976, 0xd134621f, 0xdf3d6f14, 0xcd267809, 0xc32f7502,
      0xe9105633, 0xe7195b38, 0xf5024c25, 0xfb0b412e, 0x9ad7618c, 0x94de6c87,
      0x86c57b9a, 0x88cc7691, 0xa2f355a0, 0xacfa58ab, 0xbee14fb6, 0xb0e842bd,
      0xea9f09d4, 0xe49604df, 0xf68d13c2, 0xf8841ec9, 0xd2bb3df8, 0xdcb230f3,
      0xcea927ee, 0xc0a02ae5, 0x7a47b13c, 0x744ebc37, 0x6655ab2a, 0x685ca621,
      0x42638510, 0x4c6a881b, 0x5e719f06, 0x5078920d, 0x0a0fd964, 0x0406d46f,
      0x161dc372, 0x1814ce79, 0x322bed48, 0x3c22e043, 0x2e39f75e, 0x2030fa55,
      0xec9ab701, 0xe293ba0a, 0xf088ad17, 0xfe81a01c, 0xd4be832d, 0xdab78e26,
      0xc8ac993b, 0xc6a59430, 0x9cd2df59, 0x92dbd252, 0x80c0c54f, 0x8ec9c844,
      0xa4f6eb75, 0xaaffe67e, 0xb8e4f163, 0xb6edfc68, 0x0c0a67b1, 0x02036aba,
      0x10187da7, 0x1e1170ac, 0x342e539d, 0x3a275e96, 0x283c498b, 0x26354480,
      0x7c420fe9, 0x724b02e2, 0x605015ff, 0x6e5918f4, 0x44663bc5, 0x4a6f36ce,
      0x587421d3, 0x567d2cd8, 0x37a10c7a, 0x39a80171, 0x2bb3166c, 0x25ba1b67,
      0x0f853856, 0x018c355d, 0x13972240, 0x1d9e2f4b, 0x47e96422, 0x49e06929,
      0x5bfb7e34, 0x55f2733f, 0x7fcd500e, 0x71c45d05, 0x63df4a18, 0x6dd64713,
      0xd731dcca, 0xd938d1c1, 0xcb23c6dc, 0xc52acbd7, 0xef15e8e6, 0xe11ce5ed,
      0xf307f2f0, 0xfd0efffb, 0xa779b492, 0xa970b999, 0xbb6bae84, 0xb562a38f,
      0x9f5d80be, 0x91548db5, 0x834f9aa8, 0x8d4697a3]);
  
    function expandKey128(cipherKey) {
      var b = 176, result = new Uint8Array(b);
      result.set(cipherKey);
      for (var j = 16, i = 1; j < b; ++i) {
        // RotWord
        var t1 = result[j - 3], t2 = result[j - 2],
            t3 = result[j - 1], t4 = result[j - 4];
        // SubWord
        t1 = s[t1]; t2 = s[t2]; t3 = s[t3]; t4 = s[t4];
        // Rcon
        t1 = t1 ^ rcon[i];
        for (var n = 0; n < 4; ++n) {
          result[j] = (t1 ^= result[j - 16]); j++;
          result[j] = (t2 ^= result[j - 16]); j++;
          result[j] = (t3 ^= result[j - 16]); j++;
          result[j] = (t4 ^= result[j - 16]); j++;
        }
      }
      return result;
    }
  
    function decrypt128(input, key) {
      var state = new Uint8Array(16);
      state.set(input);
      var i, j, k;
      var t, u, v;
      // AddRoundKey
      for (j = 0, k = 160; j < 16; ++j, ++k)
        state[j] ^= key[k];
      for (i = 9; i >= 1; --i) {
        // InvShiftRows
        t = state[13]; state[13] = state[9]; state[9] = state[5];
        state[5] = state[1]; state[1] = t;
        t = state[14]; u = state[10]; state[14] = state[6];
        state[10] = state[2]; state[6] = t; state[2] = u;
        t = state[15]; u = state[11]; v = state[7]; state[15] = state[3];
        state[11] = t; state[7] = u; state[3] = v;
        // InvSubBytes
        for (j = 0; j < 16; ++j)
          state[j] = inv_s[state[j]];
        // AddRoundKey
        for (j = 0, k = i * 16; j < 16; ++j, ++k)
          state[j] ^= key[k];
        // InvMixColumns
        for (j = 0; j < 16; j += 4) {
          var s0 = mix[state[j]], s1 = mix[state[j + 1]],
              s2 = mix[state[j + 2]], s3 = mix[state[j + 3]];
          t = (s0 ^ (s1 >>> 8) ^ (s1 << 24) ^ (s2 >>> 16) ^ (s2 << 16) ^
              (s3 >>> 24) ^ (s3 << 8));
          state[j] = (t >>> 24) & 0xFF;
          state[j + 1] = (t >> 16) & 0xFF;
          state[j + 2] = (t >> 8) & 0xFF;
          state[j + 3] = t & 0xFF;
        }
      }
      // InvShiftRows
      t = state[13]; state[13] = state[9]; state[9] = state[5];
      state[5] = state[1]; state[1] = t;
      t = state[14]; u = state[10]; state[14] = state[6];
      state[10] = state[2]; state[6] = t; state[2] = u;
      t = state[15]; u = state[11]; v = state[7]; state[15] = state[3];
      state[11] = t; state[7] = u; state[3] = v;
      for (j = 0; j < 16; ++j) {
        // InvSubBytes
        state[j] = inv_s[state[j]];
        // AddRoundKey
        state[j] ^= key[j];
      }
      return state;
    }
  
    function AES128Cipher(key) {
      this.key = expandKey128(key);
      this.buffer = new Uint8Array(16);
      this.bufferPosition = 0;
    }
  
    function decryptBlock2(data, finalize) {
      var i, j, ii, sourceLength = data.length,
          buffer = this.buffer, bufferLength = this.bufferPosition,
          result = [], iv = this.iv;
      for (i = 0; i < sourceLength; ++i) {
        buffer[bufferLength] = data[i];
        ++bufferLength;
        if (bufferLength < 16)
          continue;
        // buffer is full, decrypting
        var plain = decrypt128(buffer, this.key);
        // xor-ing the IV vector to get plain text
        for (j = 0; j < 16; ++j)
          plain[j] ^= iv[j];
        iv = buffer;
        result.push(plain);
        buffer = new Uint8Array(16);
        bufferLength = 0;
      }
      // saving incomplete buffer
      this.buffer = buffer;
      this.bufferLength = bufferLength;
      this.iv = iv;
      if (result.length === 0) {
        return new Uint8Array([]);
      }
      // combining plain text blocks into one
      var outputLength = 16 * result.length;
      if (finalize) {
        // undo a padding that is described in RFC 2898
        var lastBlock = result[result.length - 1];
        outputLength -= lastBlock[15];
        result[result.length - 1] = lastBlock.subarray(0, 16 - lastBlock[15]);
      }
      var output = new Uint8Array(outputLength);
      for (i = 0, j = 0, ii = result.length; i < ii; ++i, j += 16)
        output.set(result[i], j);
      return output;
    }
  
    AES128Cipher.prototype = {
      decryptBlock: function AES128Cipher_decryptBlock(data, finalize) {
        var i, sourceLength = data.length;
        var buffer = this.buffer, bufferLength = this.bufferPosition;
        // waiting for IV values -- they are at the start of the stream
        for (i = 0; bufferLength < 16 && i < sourceLength; ++i, ++bufferLength)
          buffer[bufferLength] = data[i];
        if (bufferLength < 16) {
          // need more data
          this.bufferLength = bufferLength;
          return new Uint8Array([]);
        }
        this.iv = buffer;
        this.buffer = new Uint8Array(16);
        this.bufferLength = 0;
        // starting decryption
        this.decryptBlock = decryptBlock2;
        return this.decryptBlock(data.subarray(16), finalize);
      }
    };
  
    return AES128Cipher;
  })();
  
  var CipherTransform = (function CipherTransformClosure() {
    function CipherTransform(stringCipherConstructor, streamCipherConstructor) {
      this.stringCipherConstructor = stringCipherConstructor;
      this.streamCipherConstructor = streamCipherConstructor;
    }
    CipherTransform.prototype = {
      createStream: function CipherTransform_createStream(stream) {
        var cipher = new this.streamCipherConstructor();
        return new DecryptStream(stream,
          function cipherTransformDecryptStream(data, finalize) {
            return cipher.decryptBlock(data, finalize);
          }
        );
      },
      decryptString: function CipherTransform_decryptString(s) {
        var cipher = new this.stringCipherConstructor();
        var data = stringToBytes(s);
        data = cipher.decryptBlock(data, true);
        return bytesToString(data);
      }
    };
    return CipherTransform;
  })();
  
  var CipherTransformFactory = (function CipherTransformFactoryClosure() {
    var defaultPasswordBytes = new Uint8Array([
      0x28, 0xBF, 0x4E, 0x5E, 0x4E, 0x75, 0x8A, 0x41,
      0x64, 0x00, 0x4E, 0x56, 0xFF, 0xFA, 0x01, 0x08,
      0x2E, 0x2E, 0x00, 0xB6, 0xD0, 0x68, 0x3E, 0x80,
      0x2F, 0x0C, 0xA9, 0xFE, 0x64, 0x53, 0x69, 0x7A]);
  
    function prepareKeyData(fileId, password, ownerPassword, userPassword,
                            flags, revision, keyLength, encryptMetadata) {
      var hashDataSize = 40 + ownerPassword.length + fileId.length;
      var hashData = new Uint8Array(hashDataSize), i = 0, j, n;
      if (password) {
        n = Math.min(32, password.length);
        for (; i < n; ++i)
          hashData[i] = password[i];
      }
      j = 0;
      while (i < 32) {
        hashData[i++] = defaultPasswordBytes[j++];
      }
      // as now the padded password in the hashData[0..i]
      for (j = 0, n = ownerPassword.length; j < n; ++j)
        hashData[i++] = ownerPassword[j];
      hashData[i++] = flags & 0xFF;
      hashData[i++] = (flags >> 8) & 0xFF;
      hashData[i++] = (flags >> 16) & 0xFF;
      hashData[i++] = (flags >>> 24) & 0xFF;
      for (j = 0, n = fileId.length; j < n; ++j)
        hashData[i++] = fileId[j];
      if (revision >= 4 && !encryptMetadata) {
        hashData[i++] = 0xFF;
        hashData[i++] = 0xFF;
        hashData[i++] = 0xFF;
        hashData[i++] = 0xFF;
      }
      var hash = calculateMD5(hashData, 0, i);
      var keyLengthInBytes = keyLength >> 3;
      if (revision >= 3) {
        for (j = 0; j < 50; ++j) {
           hash = calculateMD5(hash, 0, keyLengthInBytes);
        }
      }
      var encryptionKey = hash.subarray(0, keyLengthInBytes);
      var cipher, checkData;
  
      if (revision >= 3) {
        for (i = 0; i < 32; ++i)
          hashData[i] = defaultPasswordBytes[i];
        for (j = 0, n = fileId.length; j < n; ++j)
          hashData[i++] = fileId[j];
        cipher = new ARCFourCipher(encryptionKey);
        var checkData = cipher.encryptBlock(calculateMD5(hashData, 0, i));
        n = encryptionKey.length;
        var derivedKey = new Uint8Array(n), k;
        for (j = 1; j <= 19; ++j) {
          for (k = 0; k < n; ++k)
            derivedKey[k] = encryptionKey[k] ^ j;
          cipher = new ARCFourCipher(derivedKey);
          checkData = cipher.encryptBlock(checkData);
        }
        for (j = 0, n = checkData.length; j < n; ++j) {
          if (userPassword[j] != checkData[j])
            return null;
        }
      } else {
        cipher = new ARCFourCipher(encryptionKey);
        checkData = cipher.encryptBlock(defaultPasswordBytes);
        for (j = 0, n = checkData.length; j < n; ++j) {
          if (userPassword[j] != checkData[j])
            return null;
        }
      }
      return encryptionKey;
    }
    function decodeUserPassword(password, ownerPassword, revision, keyLength) {
      var hashData = new Uint8Array(32), i = 0, j, n;
      n = Math.min(32, password.length);
      for (; i < n; ++i)
        hashData[i] = password[i];
      j = 0;
      while (i < 32) {
        hashData[i++] = defaultPasswordBytes[j++];
      }
      var hash = calculateMD5(hashData, 0, i);
      var keyLengthInBytes = keyLength >> 3;
      if (revision >= 3) {
        for (j = 0; j < 50; ++j) {
           hash = calculateMD5(hash, 0, hash.length);
        }
      }
  
      var cipher, userPassword;
      if (revision >= 3) {
        userPassword = ownerPassword;
        var derivedKey = new Uint8Array(keyLengthInBytes), k;
        for (j = 19; j >= 0; j--) {
          for (k = 0; k < keyLengthInBytes; ++k)
            derivedKey[k] = hash[k] ^ j;
          cipher = new ARCFourCipher(derivedKey);
          userPassword = cipher.encryptBlock(userPassword);
        }
      } else {
        cipher = new ARCFourCipher(hash.subarray(0, keyLengthInBytes));
        userPassword = cipher.encryptBlock(ownerPassword);
      }
      return userPassword;
    }
  
    var identityName = new Name('Identity');
  
    function CipherTransformFactory(dict, fileId, password) {
      var filter = dict.get('Filter');
      if (!isName(filter) || filter.name != 'Standard')
        error('Error: unknown encryption method');
      this.dict = dict;
      var algorithm = dict.get('V');
      if (!isInt(algorithm) ||
        (algorithm != 1 && algorithm != 2 && algorithm != 4))
        error('Error: unsupported encryption algorithm');
      this.algorithm = algorithm;
      var keyLength = dict.get('Length') || 40;
      if (!isInt(keyLength) ||
        keyLength < 40 || (keyLength % 8) !== 0)
        error('Error: invalid key length');
      // prepare keys
      var ownerPassword = stringToBytes(dict.get('O')).subarray(0, 32);
      var userPassword = stringToBytes(dict.get('U')).subarray(0, 32);
      var flags = dict.get('P');
      var revision = dict.get('R');
      var encryptMetadata = algorithm == 4 &&  // meaningful when V is 4
        dict.get('EncryptMetadata') !== false; // makes true as default value
      this.encryptMetadata = encryptMetadata;
  
      var fileIdBytes = stringToBytes(fileId);
      var passwordBytes;
      if (password)
        passwordBytes = stringToBytes(password);
  
      var encryptionKey = prepareKeyData(fileIdBytes, passwordBytes,
                                         ownerPassword, userPassword, flags,
                                         revision, keyLength, encryptMetadata);
      if (!encryptionKey && !password) {
        throw new PasswordException('No password given',
                                    PasswordResponses.NEED_PASSWORD);
      } else if (!encryptionKey && password) {
        // Attempting use the password as an owner password
        var decodedPassword = decodeUserPassword(passwordBytes, ownerPassword,
                                                 revision, keyLength);
        encryptionKey = prepareKeyData(fileIdBytes, decodedPassword,
                                       ownerPassword, userPassword, flags,
                                       revision, keyLength, encryptMetadata);
      }
  
      if (!encryptionKey)
        throw new PasswordException('Incorrect Password',
                                    PasswordResponses.INCORRECT_PASSWORD);
  
      this.encryptionKey = encryptionKey;
  
      if (algorithm == 4) {
        this.cf = dict.get('CF');
        this.stmf = dict.get('StmF') || identityName;
        this.strf = dict.get('StrF') || identityName;
        this.eff = dict.get('EFF') || this.strf;
      }
    }
  
    function buildObjectKey(num, gen, encryptionKey, isAes) {
      var key = new Uint8Array(encryptionKey.length + 9), i, n;
      for (i = 0, n = encryptionKey.length; i < n; ++i)
        key[i] = encryptionKey[i];
      key[i++] = num & 0xFF;
      key[i++] = (num >> 8) & 0xFF;
      key[i++] = (num >> 16) & 0xFF;
      key[i++] = gen & 0xFF;
      key[i++] = (gen >> 8) & 0xFF;
      if (isAes) {
        key[i++] = 0x73;
        key[i++] = 0x41;
        key[i++] = 0x6C;
        key[i++] = 0x54;
      }
      var hash = calculateMD5(key, 0, i);
      return hash.subarray(0, Math.min(encryptionKey.length + 5, 16));
    }
  
    function buildCipherConstructor(cf, name, num, gen, key) {
      var cryptFilter = cf.get(name.name);
      var cfm;
      if (cryptFilter !== null && cryptFilter !== undefined)
        cfm = cryptFilter.get('CFM');
      if (!cfm || cfm.name == 'None') {
        return function cipherTransformFactoryBuildCipherConstructorNone() {
          return new NullCipher();
        };
      }
      if ('V2' == cfm.name) {
        return function cipherTransformFactoryBuildCipherConstructorV2() {
          return new ARCFourCipher(
            buildObjectKey(num, gen, key, false));
        };
      }
      if ('AESV2' == cfm.name) {
        return function cipherTransformFactoryBuildCipherConstructorAESV2() {
          return new AES128Cipher(
            buildObjectKey(num, gen, key, true));
        };
      }
      error('Unknown crypto method');
    }
  
    CipherTransformFactory.prototype = {
      createCipherTransform:
        function CipherTransformFactory_createCipherTransform(num, gen) {
        if (this.algorithm == 4) {
          return new CipherTransform(
            buildCipherConstructor(this.cf, this.stmf,
              num, gen, this.encryptionKey),
            buildCipherConstructor(this.cf, this.strf,
              num, gen, this.encryptionKey));
        }
        // algorithms 1 and 2
        var key = buildObjectKey(num, gen, this.encryptionKey, false);
        var cipherConstructor = function buildCipherCipherConstructor() {
          return new ARCFourCipher(key);
        };
        return new CipherTransform(cipherConstructor, cipherConstructor);
      }
    };
  
    return CipherTransformFactory;
  })();
  
  