/**
* CBCMode
*
* An ActionScript 3 implementation of the CBC confidentiality mode
* Copyright (c) 2007 Henri Torgemane
*
* See LICENSE.txt for full license information.
*/
package com.hurlant.crypto.symmetric
{
import flash.utils.ByteArray;
/**
* CBC confidentiality mode. why not.
*/
public class CBCMode extends IVMode implements IMode
{
public function CBCMode(key:ISymmetricKey, padding:IPad = null) {
super(key, padding);
}
public function encrypt(src:ByteArray):void {
padding.pad(src);
var vector:ByteArray = getIV4e();
for (var i:uint=0;i<src.length;i+=blockSize) {
for (var j:uint=0;j<blockSize;j++) {
src[i+j] ^= vector[j];
}
key.encrypt(src, i);
vector.position=0;
vector.writeBytes(src, i, blockSize);
}
}
public function decrypt(src:ByteArray):void {
var vector:ByteArray = getIV4d();
var tmp:ByteArray = new ByteArray;
for (var i:uint=0;i<src.length;i+=blockSize) {
tmp.position=0;
tmp.writeBytes(src, i, blockSize);
key.decrypt(src, i);
for (var j:uint=0;j<blockSize;j++) {
src[i+j] ^= vector[j];
}
vector.position=0;
vector.writeBytes(tmp, 0, blockSize);
}
padding.unpad(src);
}
public function toString():String {
return key.toString()+"-cbc";
}
}
}
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