node/node_modules/socket.io-client/lib/vendor/web-socket-js/flash-src/com/hurlant/crypto/symmetric/PKCS5.as

   1 /**
   2  * PKCS5
   3  *
   4  * A padding implementation of PKCS5.
   5  * Copyright (c) 2007 Henri Torgemane
   6  *
   7  * See LICENSE.txt for full license information.
   8  */
   9 package com.hurlant.crypto.symmetric
  10 {
  11         import flash.utils.ByteArray;
  12
  13         public class PKCS5 implements IPad
  14         {
  15                 private var blockSize:uint;
  16
  17                 public function PKCS5(blockSize:uint=0) {
  18                         this.blockSize = blockSize;
  19                 }
  20
  21                 public function pad(a:ByteArray):void {
  22                         var c:uint = blockSize-a.length%blockSize;
  23                         for (var i:uint=0;i<c;i++){
  24                                 a[a.length] = c;
  25                         }
  26                 }
  27                 public function unpad(a:ByteArray):void {
  28                         var c:uint = a.length%blockSize;
  29                         if (c!=0) throw new Error("PKCS#5::unpad: ByteArray.length isn't a multiple of the blockSize");
  30                         c = a[a.length-1];
  31                         for (var i:uint=c;i>0;i--) {
  32                                 var v:uint = a[a.length-1];
  33                                 a.length--;
  34                                 if (c!=v) throw new Error("PKCS#5:unpad: Invalid padding value. expected ["+c+"], found ["+v+"]");
  35                         }
  36                         // that is all.
  37                 }
  38
  39                 public function setBlockSize(bs:uint):void {
  40                         blockSize = bs;
  41                 }
  42
  43         }
  44 }