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

   1 /**\r
   2  * IVMode\r
   3  * \r
   4  * An abstract class for confidentialy modes that rely on an initialization vector.\r
   5  * Copyright (c) 2007 Henri Torgemane\r
   6  * \r
   7  * See LICENSE.txt for full license information.\r
   8  */\r
   9 package com.hurlant.crypto.symmetric\r
  10 {\r
  11         import com.hurlant.crypto.prng.Random;\r
  12         import com.hurlant.crypto.tests.TestCase;\r
  13         import com.hurlant.util.Memory;\r
  14         \r
  15         import flash.utils.ByteArray;\r
  16         \r
  17         /**\r
  18          * An "abtract" class to avoid redundant code in subclasses\r
  19          */\r
  20         public class IVMode\r
  21         {\r
  22                 protected var key:ISymmetricKey;\r
  23                 protected var padding:IPad;\r
  24                 // random generator used to generate IVs\r
  25                 protected var prng:Random;\r
  26                 // optional static IV. used for testing only.\r
  27                 protected var iv:ByteArray;\r
  28                 // generated IV is stored here.\r
  29                 protected var lastIV:ByteArray;\r
  30                 protected var blockSize:uint;\r
  31                 \r
  32                 \r
  33                 public function IVMode(key:ISymmetricKey, padding:IPad = null) {\r
  34                         this.key = key;\r
  35                         blockSize = key.getBlockSize();\r
  36                         if (padding == null) {\r
  37                                 padding = new PKCS5(blockSize);\r
  38                         } else {\r
  39                                 padding.setBlockSize(blockSize);\r
  40                         }\r
  41                         this.padding = padding;\r
  42                         \r
  43                         prng = new Random;\r
  44                         iv = null;\r
  45                         lastIV = new ByteArray;\r
  46                 }\r
  47                 \r
  48                 public function getBlockSize():uint {\r
  49                         return key.getBlockSize();\r
  50                 }\r
  51                 public function dispose():void {\r
  52                         var i:uint;\r
  53                         if (iv != null) {\r
  54                                 for (i=0;i<iv.length;i++) {\r
  55                                         iv[i] = prng.nextByte();\r
  56                                 }\r
  57                                 iv.length=0;\r
  58                                 iv = null;\r
  59                         }\r
  60                         if (lastIV != null) {\r
  61                                 for (i=0;i<iv.length;i++) {\r
  62                                         lastIV[i] = prng.nextByte();\r
  63                                 }\r
  64                                 lastIV.length=0;\r
  65                                 lastIV=null;\r
  66                         }\r
  67                         key.dispose();\r
  68                         key = null;\r
  69                         padding = null;\r
  70                         prng.dispose();\r
  71                         prng = null;\r
  72                         Memory.gc();\r
  73                 }\r
  74                 /**\r
  75                  * Optional function to force the IV value.\r
  76                  * Normally, an IV gets generated randomly at every encrypt() call.\r
  77                  * Also, use this to set the IV before calling decrypt()\r
  78                  * (if not set before decrypt(), the IV is read from the beginning of the stream.)\r
  79                  */\r
  80                 public function set IV(value:ByteArray):void {\r
  81                         iv = value;\r
  82                         lastIV.length=0;\r
  83                         lastIV.writeBytes(iv);\r
  84                 }\r
  85                 public function get IV():ByteArray {\r
  86                         return lastIV;\r
  87                 }\r
  88                 \r
  89                 protected function getIV4e():ByteArray {\r
  90                         var vec:ByteArray = new ByteArray;\r
  91                         if (iv) {\r
  92                                 vec.writeBytes(iv);\r
  93                         } else {\r
  94                                 prng.nextBytes(vec, blockSize);\r
  95                         }\r
  96                         lastIV.length=0;\r
  97                         lastIV.writeBytes(vec);\r
  98                         return vec;\r
  99                 }\r
 100                 protected function getIV4d():ByteArray {\r
 101                         var vec:ByteArray = new ByteArray;\r
 102                         if (iv) {\r
 103                                 vec.writeBytes(iv);\r
 104                         } else {\r
 105                                 throw new Error("an IV must be set before calling decrypt()");\r
 106                         }\r
 107                         return vec;\r
 108                 }\r
 109         }\r
 110 }