001/* 002 * $Id: AESCipher.java 4784 2011-03-15 08:33:00Z blowagie $ 003 * 004 * This file is part of the iText (R) project. 005 * Copyright (c) 1998-2011 1T3XT BVBA 006 * Authors: Bruno Lowagie, Paulo Soares, et al. 007 * 008 * This program is free software; you can redistribute it and/or modify 009 * it under the terms of the GNU Affero General Public License version 3 010 * as published by the Free Software Foundation with the addition of the 011 * following permission added to Section 15 as permitted in Section 7(a): 012 * FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY 1T3XT, 013 * 1T3XT DISCLAIMS THE WARRANTY OF NON INFRINGEMENT OF THIRD PARTY RIGHTS. 014 * 015 * This program is distributed in the hope that it will be useful, but 016 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 017 * or FITNESS FOR A PARTICULAR PURPOSE. 018 * See the GNU Affero General Public License for more details. 019 * You should have received a copy of the GNU Affero General Public License 020 * along with this program; if not, see http://www.gnu.org/licenses or write to 021 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, 022 * Boston, MA, 02110-1301 USA, or download the license from the following URL: 023 * http://itextpdf.com/terms-of-use/ 024 * 025 * The interactive user interfaces in modified source and object code versions 026 * of this program must display Appropriate Legal Notices, as required under 027 * Section 5 of the GNU Affero General Public License. 028 * 029 * In accordance with Section 7(b) of the GNU Affero General Public License, 030 * a covered work must retain the producer line in every PDF that is created 031 * or manipulated using iText. 032 * 033 * You can be released from the requirements of the license by purchasing 034 * a commercial license. Buying such a license is mandatory as soon as you 035 * develop commercial activities involving the iText software without 036 * disclosing the source code of your own applications. 037 * These activities include: offering paid services to customers as an ASP, 038 * serving PDFs on the fly in a web application, shipping iText with a closed 039 * source product. 040 * 041 * For more information, please contact iText Software Corp. at this 042 * address: sales@itextpdf.com 043 */ 044package com.itextpdf.text.pdf.crypto; 045 046import org.bouncycastle.crypto.BlockCipher; 047import org.bouncycastle.crypto.engines.AESFastEngine; 048import org.bouncycastle.crypto.modes.CBCBlockCipher; 049import org.bouncycastle.crypto.paddings.PaddedBufferedBlockCipher; 050import org.bouncycastle.crypto.params.KeyParameter; 051import org.bouncycastle.crypto.params.ParametersWithIV; 052 053/** 054 * Creates an AES Cipher with CBC and padding PKCS5/7. 055 * @author Paulo Soares 056 */ 057public class AESCipher { 058 private PaddedBufferedBlockCipher bp; 059 060 /** Creates a new instance of AESCipher */ 061 public AESCipher(boolean forEncryption, byte[] key, byte[] iv) { 062 BlockCipher aes = new AESFastEngine(); 063 BlockCipher cbc = new CBCBlockCipher(aes); 064 bp = new PaddedBufferedBlockCipher(cbc); 065 KeyParameter kp = new KeyParameter(key); 066 ParametersWithIV piv = new ParametersWithIV(kp, iv); 067 bp.init(forEncryption, piv); 068 } 069 070 public byte[] update(byte[] inp, int inpOff, int inpLen) { 071 int neededLen = bp.getUpdateOutputSize(inpLen); 072 byte[] outp = null; 073 if (neededLen > 0) 074 outp = new byte[neededLen]; 075 else 076 neededLen = 0; 077 bp.processBytes(inp, inpOff, inpLen, outp, 0); 078 return outp; 079 } 080 081 public byte[] doFinal() { 082 int neededLen = bp.getOutputSize(0); 083 byte[] outp = new byte[neededLen]; 084 int n = 0; 085 try { 086 n = bp.doFinal(outp, 0); 087 } catch (Exception ex) { 088 return outp; 089 } 090 if (n != outp.length) { 091 byte[] outp2 = new byte[n]; 092 System.arraycopy(outp, 0, outp2, 0, n); 093 return outp2; 094 } 095 else 096 return outp; 097 } 098 099}