001    /*
002     * Cumulus4j - Securing your data in the cloud - http://cumulus4j.org
003     * Copyright (C) 2011 NightLabs Consulting GmbH
004     *
005     * This program is free software: you can redistribute it and/or modify
006     * it under the terms of the GNU Affero General Public License as
007     * published by the Free Software Foundation, either version 3 of the
008     * License, or (at your option) any later version.
009     *
010     * This program is distributed in the hope that it will be useful,
011     * but WITHOUT ANY WARRANTY; without even the implied warranty of
012     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
013     * GNU Affero General Public License for more details.
014     *
015     * You should have received a copy of the GNU Affero General Public License
016     * along with this program.  If not, see <http://www.gnu.org/licenses/>.
017     */
018    package org.cumulus4j.crypto.internal.symmetric.mode;
019    
020    import org.bouncycastle.crypto.BlockCipher;
021    import org.bouncycastle.crypto.modes.OFBBlockCipher;
022    
023    /**
024     * @author Marco หงุ่ยตระกูล-Schulze - marco at nightlabs dot de
025     */
026    public class C4jOFBBlockCipher extends OFBBlockCipher
027    {
028            private static int determineBitBlockSize(BlockCipher engine, String modeName)
029            {
030                    if (modeName.length() != 3)
031        {
032            int wordSize = Integer.parseInt(modeName.substring(3));
033            return wordSize;
034        }
035                    else
036                            return 8 * engine.getBlockSize();
037            }
038    
039            public C4jOFBBlockCipher(BlockCipher engine, String modeName) {
040                    super(engine, determineBitBlockSize(engine, modeName));
041            }
042    }