/*
* $Id: AESCipher.java 4784 2011-03-15 08:33:00Z blowagie $
*
* This file is part of the iText (R) project.
* Copyright (c) 1998-2011 1T3XT BVBA
* Authors: Bruno Lowagie, Paulo Soares, et al.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License version 3
* as published by the Free Software Foundation with the addition of the
* following permission added to Section 15 as permitted in Section 7(a):
* FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY 1T3XT,
* 1T3XT DISCLAIMS THE WARRANTY OF NON INFRINGEMENT OF THIRD PARTY RIGHTS.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU Affero General Public License for more details.
* You should have received a copy of the GNU Affero General Public License
* along with this program; if not, see http://www.gnu.org/licenses or write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA, 02110-1301 USA, or download the license from the following URL:
* http://itextpdf.com/terms-of-use/
*
* The interactive user interfaces in modified source and object code versions
* of this program must display Appropriate Legal Notices, as required under
* Section 5 of the GNU Affero General Public License.
*
* In accordance with Section 7(b) of the GNU Affero General Public License,
* a covered work must retain the producer line in every PDF that is created
* or manipulated using iText.
*
* You can be released from the requirements of the license by purchasing
* a commercial license. Buying such a license is mandatory as soon as you
* develop commercial activities involving the iText software without
* disclosing the source code of your own applications.
* These activities include: offering paid services to customers as an ASP,
* serving PDFs on the fly in a web application, shipping iText with a closed
* source product.
*
* For more information, please contact iText Software Corp. at this
* address: [email protected]
*/
package com.itextpdf.text.pdf.crypto;
import org.bouncycastle.crypto.BlockCipher;
import org.bouncycastle.crypto.engines.AESFastEngine;
import org.bouncycastle.crypto.modes.CBCBlockCipher;
import org.bouncycastle.crypto.paddings.PaddedBufferedBlockCipher;
import org.bouncycastle.crypto.params.KeyParameter;
import org.bouncycastle.crypto.params.ParametersWithIV;
/**
* Creates an AES Cipher with CBC and padding PKCS5/7.
* @author Paulo Soares
*/
public class AESCipher {
private PaddedBufferedBlockCipher bp;
/** Creates a new instance of AESCipher */
public AESCipher(boolean forEncryption, byte[] key, byte[] iv) {
BlockCipher aes = new AESFastEngine();
BlockCipher cbc = new CBCBlockCipher(aes);
bp = new PaddedBufferedBlockCipher(cbc);
KeyParameter kp = new KeyParameter(key);
ParametersWithIV piv = new ParametersWithIV(kp, iv);
bp.init(forEncryption, piv);
}
public byte[] update(byte[] inp, int inpOff, int inpLen) {
int neededLen = bp.getUpdateOutputSize(inpLen);
byte[] outp = null;
if (neededLen > 0)
outp = new byte[neededLen];
else
neededLen = 0;
bp.processBytes(inp, inpOff, inpLen, outp, 0);
return outp;
}
public byte[] doFinal() {
int neededLen = bp.getOutputSize(0);
byte[] outp = new byte[neededLen];
int n = 0;
try {
n = bp.doFinal(outp, 0);
} catch (Exception ex) {
return outp;
}
if (n != outp.length) {
byte[] outp2 = new byte[n];
System.arraycopy(outp, 0, outp2, 0, n);
return outp2;
}
else
return outp;
}
}
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