vnfmarket/src/main/webapp/vnfmarket/node_modules/socket.io-client/lib/vendor/web-socket-js/flash-src/com/hurlant/crypto/prng/ARC4.as

   1 /**\r
   2  * ARC4\r
   3  * \r
   4  * An ActionScript 3 implementation of RC4\r
   5  * Copyright (c) 2007 Henri Torgemane\r
   6  * \r
   7  * Derived from:\r
   8  *              The jsbn library, Copyright (c) 2003-2005 Tom Wu\r
   9  * \r
  10  * See LICENSE.txt for full license information.\r
  11  */\r
  12 package com.hurlant.crypto.prng\r
  13 {\r
  14         import com.hurlant.crypto.symmetric.IStreamCipher;\r
  15         import com.hurlant.util.Memory;\r
  16         \r
  17         import flash.utils.ByteArray;\r
  18 \r
  19         public class ARC4 implements IPRNG, IStreamCipher {\r
  20                 private var i:int = 0;\r
  21                 private var j:int = 0;\r
  22                 private var S:ByteArray;\r
  23                 private const psize:uint = 256;\r
  24                 public function ARC4(key:ByteArray = null){\r
  25                         S = new ByteArray;\r
  26                         if (key) {\r
  27                                 init(key);\r
  28                         }\r
  29                 }\r
  30                 public function getPoolSize():uint {\r
  31                         return psize;\r
  32                 }\r
  33                 public function init(key:ByteArray):void {\r
  34                         var i:int;\r
  35                         var j:int;\r
  36                         var t:int;\r
  37                         for (i=0; i<256; ++i) {\r
  38                                 S[i] = i;\r
  39                         }\r
  40                         j=0;\r
  41                         for (i=0; i<256; ++i) {\r
  42                                 j = (j + S[i] + key[i%key.length]) & 255;\r
  43                                 t = S[i];\r
  44                                 S[i] = S[j];\r
  45                                 S[j] = t;\r
  46                         }\r
  47                         this.i=0;\r
  48                         this.j=0;\r
  49                 }\r
  50                 public function next():uint {\r
  51                         var t:int;\r
  52                         i = (i+1)&255;\r
  53                         j = (j+S[i])&255;\r
  54                         t = S[i];\r
  55                         S[i] = S[j];\r
  56                         S[j] = t;\r
  57                         return S[(t+S[i])&255];\r
  58                 }\r
  59 \r
  60                 public function getBlockSize():uint {\r
  61                         return 1;\r
  62                 }\r
  63                 \r
  64                 public function encrypt(block:ByteArray):void {\r
  65                         var i:uint = 0;\r
  66                         while (i<block.length) {\r
  67                                 block[i++] ^= next();\r
  68                         }\r
  69                 }\r
  70                 public function decrypt(block:ByteArray):void {\r
  71                         encrypt(block); // the beauty of XOR.\r
  72                 }\r
  73                 public function dispose():void {\r
  74                         var i:uint = 0;\r
  75                         if (S!=null) {\r
  76                                 for (i=0;i<S.length;i++) {\r
  77                                         S[i] = Math.random()*256;\r
  78                                 }\r
  79                                 S.length=0;\r
  80                                 S = null;\r
  81                         }\r
  82                         this.i = 0;\r
  83                         this.j = 0;\r
  84                         Memory.gc();\r
  85                 }\r
  86                 public function toString():String {\r
  87                         return "rc4";\r
  88                 }\r
  89         }\r
  90 }