/js/lib/Socket.IO-node/support/socket.io-client/lib/vendor/web-socket-js/flash-src/com/hurlant/crypto/symmetric/CTRMode.as
ActionScript | 58 lines | 43 code | 7 blank | 8 comment | 4 complexity | afede4e57e6ec738b4d24cca54b25290 MD5 | raw file
Possible License(s): GPL-2.0, LGPL-2.1, MPL-2.0-no-copyleft-exception, BSD-3-Clause
- /**
- * CTRMode
- *
- * An ActionScript 3 implementation of the counter confidentiality mode
- * Copyright (c) 2007 Henri Torgemane
- *
- * See LICENSE.txt for full license information.
- */
- package com.hurlant.crypto.symmetric
- {
- import flash.utils.ByteArray;
-
- public class CTRMode extends IVMode implements IMode
- {
-
- public function CTRMode(key:ISymmetricKey, padding:IPad = null) {
- super(key, padding);
- }
-
- public function encrypt(src:ByteArray):void
- {
- padding.pad(src);
- var vector:ByteArray = getIV4e();
- core(src, vector);
- }
-
- public function decrypt(src:ByteArray):void
- {
- var vector:ByteArray = getIV4d();
- core(src, vector);
- padding.unpad(src);
- }
-
- private function core(src:ByteArray, iv:ByteArray):void {
- var X:ByteArray = new ByteArray;
- var Xenc:ByteArray = new ByteArray;
- X.writeBytes(iv);
- for (var i:uint=0;i<src.length;i+=blockSize) {
- Xenc.position=0;
- Xenc.writeBytes(X);
- key.encrypt(Xenc);
- for (var j:uint=0;j<blockSize;j++) {
- src[i+j] ^= Xenc[j];
- }
-
- for (j=blockSize-1;j>=0;--j) {
- X[j]++;
- if (X[j]!=0)
- break;
- }
- }
- }
- public function toString():String {
- return key.toString()+"-ctr";
- }
-
- }
- }