| /* BlockCipherParameters.java -- |
| Copyright (C) 2002, 2003, 2006 Free Software Foundation, Inc. |
| |
| This file is a part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2 of the License, or (at |
| your option) any later version. |
| |
| GNU Classpath 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 |
| General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; if not, write to the Free Software |
| Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 |
| USA |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| |
| package gnu.javax.crypto.jce.params; |
| |
| import gnu.java.security.Configuration; |
| import gnu.javax.crypto.jce.spec.BlockCipherParameterSpec; |
| |
| import java.io.IOException; |
| import java.math.BigInteger; |
| |
| import java.security.AlgorithmParametersSpi; |
| import java.security.spec.AlgorithmParameterSpec; |
| import java.security.spec.InvalidParameterSpecException; |
| import java.util.logging.Logger; |
| |
| import javax.crypto.spec.IvParameterSpec; |
| |
| /** |
| * An implementation of algorithm parameters for the GNU block ciphers. This |
| * encompasses the cipher's block size, its key size, and an optional |
| * initialization vector (IV). |
| */ |
| public class BlockCipherParameters |
| extends AlgorithmParametersSpi |
| { |
| private static final Logger log = Logger.getLogger(BlockCipherParameters.class.getName()); |
| /** The underlying block cipher specification. */ |
| protected BlockCipherParameterSpec cipherSpec; |
| private static final String DEFAULT_FORMAT = "ASN.1"; |
| |
| /** |
| * Return these parameters encoded in ASN.1 (DER). |
| * <p> |
| * For GNU block ciphers we will define these parameters as |
| * <pre> |
| * BlockCipherParameters ::= SEQUENCE { |
| * blockSize INTEGER, |
| * keySize INTEGER, |
| * initializationVector OCTET STRING OPTIONAL } |
| * </pre> |
| * |
| * @return The parameters, encoded an an ASN.1 DER sequence. |
| * @throws java.io.IOException If encoding these parameters fails. |
| */ |
| protected byte[] engineGetEncoded() throws IOException |
| { |
| return engineGetEncoded(DEFAULT_FORMAT); |
| } |
| |
| protected byte[] engineGetEncoded(String format) throws IOException |
| { |
| if (! format.equalsIgnoreCase(DEFAULT_FORMAT) |
| && ! format.equalsIgnoreCase("asn1")) |
| throw new IOException("unknown format \"" + format + "\""); |
| DERWriter writer = new DERWriter(); |
| int cipherBlockSize = cipherSpec.getBlockSize(); |
| int cipherKeySize = cipherSpec.getKeySize(); |
| byte[] iv = cipherSpec.getIV(); |
| return writer.joinarrays( |
| writer.writeBigInteger(BigInteger.valueOf(cipherBlockSize)), |
| writer.writeBigInteger(BigInteger.valueOf(cipherKeySize)), |
| (iv != null) ? writer.writeBigInteger(new BigInteger(iv)) |
| : new byte[0]); |
| } |
| |
| protected void engineInit(AlgorithmParameterSpec spec) |
| throws InvalidParameterSpecException |
| { |
| if (spec instanceof BlockCipherParameterSpec) |
| cipherSpec = (BlockCipherParameterSpec) spec; |
| else |
| throw new InvalidParameterSpecException(); |
| } |
| |
| protected void engineInit(byte[] encoded, String format) throws IOException |
| { |
| if (! format.equalsIgnoreCase(DEFAULT_FORMAT) |
| && ! format.equalsIgnoreCase("ASN1")) |
| throw new IOException("invalid format: only accepts ASN.1"); |
| engineInit(encoded); |
| } |
| |
| protected void engineInit(byte[] encoded) throws IOException |
| { |
| DERReader reader = new DERReader(encoded); |
| int bs = reader.getBigInteger().intValue(); |
| int ks = reader.getBigInteger().intValue(); |
| byte[] iv = null; |
| if (reader.hasMorePrimitives()) |
| iv = reader.getBigInteger().toByteArray(); |
| cipherSpec = new BlockCipherParameterSpec(iv, bs, ks); |
| if (Configuration.DEBUG) |
| log.fine("cipherSpec: " + cipherSpec); |
| } |
| |
| protected AlgorithmParameterSpec engineGetParameterSpec(Class c) |
| throws InvalidParameterSpecException |
| { |
| if (c.isInstance(cipherSpec)) |
| return cipherSpec; |
| if (IvParameterSpec.class.isAssignableFrom(c)) |
| { |
| IvParameterSpec result = new IvParameterSpec(cipherSpec.getIV()); |
| return result; |
| } |
| throw new InvalidParameterSpecException(); |
| } |
| |
| protected String engineToString() |
| { |
| return cipherSpec.toString(); |
| } |
| } |