package gnu.crypto.key.dh;
// ----------------------------------------------------------------------------
// $Id: DHKeyPairRawCodec.java,v 1.2 2005/10/06 04:24:16 rsdio Exp $
//
// Copyright (C) 2003 Free Software Foundation, Inc.
//
// This file is part of GNU Crypto.
//
// GNU Crypto 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, or (at your option)
// any later version.
//
// GNU Crypto 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 this program; see the file COPYING. If not, write to the
//
// Free Software Foundation Inc.,
// 51 Franklin Street, 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
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// 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.
// ----------------------------------------------------------------------------
import gnu.crypto.Registry;
import gnu.crypto.key.IKeyPairCodec;
import java.io.ByteArrayOutputStream;
import java.math.BigInteger;
import java.security.PrivateKey;
import java.security.PublicKey;
/**
* <p>An object that implements the {@link IKeyPairCodec} operations for the
* <i>Raw</i> format to use with Diffie-Hellman keypairs.</p>
*
* @version $Revision: 1.2 $
*/
public class DHKeyPairRawCodec implements IKeyPairCodec {
// Constants and variables
// -------------------------------------------------------------------------
// Constructor(s)
// -------------------------------------------------------------------------
// implicit 0-arguments ctor
// Class methods
// -------------------------------------------------------------------------
// Instance methods
// -------------------------------------------------------------------------
// gnu.crypto.keys.IKeyPairCodec interface implementation -------------------
public int getFormatID() {
return RAW_FORMAT;
}
/**
* <p>Returns the encoded form of the designated Diffie-Hellman public key
* according to the <i>Raw</i> format supported by this library.</p>
*
* <p>The <i>Raw</i> format for a DH public key, in this implementation, is
* a byte sequence consisting of the following:</p>
*
* <ol>
* <li>4-byte magic consisting of the value of the literal
* {@link Registry#MAGIC_RAW_DH_PUBLIC_KEY},<li>
* <li>1-byte version consisting of the constant: 0x01,</li>
* <li>4-byte count of following bytes representing the DH parameter
* <code>q</code> in internet order,</li>
* <li>n-bytes representation of a {@link BigInteger} obtained by invoking
* the <code>toByteArray()</code> method on the DH parameter <code>q</code>,</li>
* <li>4-byte count of following bytes representing the DH parameter
* <code>p</code> in internet order,</li>
* <li>n-bytes representation of a {@link BigInteger} obtained by invoking
* the <code>toByteArray()</code> method on the DH parameter <code>p</code>,</li>
* <li>4-byte count of following bytes representing the DH parameter
* <code>g</code>,</li>
* <li>n-bytes representation of a {@link BigInteger} obtained by invoking
* the <code>toByteArray()</code> method on the DH parameter <code>g</code>,</li>
* <li>4-byte count of following bytes representing the DH parameter
* <code>y</code>,</li>
* <li>n-bytes representation of a {@link BigInteger} obtained by invoking
* the <code>toByteArray()</code> method on the DH parameter <code>y</code>,</li>
* </ol>
*
* @param key the key to encode.
* @return the <i>Raw</i> format encoding of the designated key.
* @throws IllegalArgumentException if the designated key is not a DH one.
* @see Registry#MAGIC_RAW_DH_PUBLIC_KEY
*/
public byte[] encodePublicKey(PublicKey key) {
if (!(key instanceof GnuDHPublicKey)) {
throw new IllegalArgumentException("key");
}
GnuDHPublicKey dhKey = (GnuDHPublicKey) key;
ByteArrayOutputStream baos = new ByteArrayOutputStream();
// magic
baos.write(Registry.MAGIC_RAW_DH_PUBLIC_KEY[0]);
baos.write(Registry.MAGIC_RAW_DH_PUBLIC_KEY[1]);
baos.write(Registry.MAGIC_RAW_DH_PUBLIC_KEY[2]);
baos.write(Registry.MAGIC_RAW_DH_PUBLIC_KEY[3]);
// version
baos.write(0x01);
// q
byte[] buffer = dhKey.getQ().toByteArray();
int length = buffer.length;
baos.write( length >>> 24 );
baos.write((length >>> 16) & 0xFF);
baos.write((length >>> 8) & 0xFF);
baos.write( length & 0xFF);
baos.write(buffer, 0, length);
// p
buffer = dhKey.getParams().getP().toByteArray();
length = buffer.length;
baos.write( length >>> 24 );
baos.write((length >>> 16) & 0xFF);
baos.write((length >>> 8) & 0xFF);
baos.write( length & 0xFF);
baos.write(buffer, 0, length);
// g
buffer = dhKey.getParams().getG().toByteArray();
length = buffer.length;
baos.write( length >>> 24 );
baos.write((length >>> 16) & 0xFF);
baos.write((length >>> 8) & 0xFF);
baos.write( length & 0xFF);
baos.write(buffer, 0, length);
// y
buffer = dhKey.getY().toByteArray();
length = buffer.length;
baos.write( length >>> 24 );
baos.write((length >>> 16) & 0xFF);
baos.write((length >>> 8) & 0xFF);
baos.write( length & 0xFF);
baos.write(buffer, 0, length);
return baos.toByteArray();
}
public PublicKey decodePublicKey(byte[] k) {
// magic
if (k[0] != Registry.MAGIC_RAW_DH_PUBLIC_KEY[0]
|| k[1] != Registry.MAGIC_RAW_DH_PUBLIC_KEY[1]
|| k[2] != Registry.MAGIC_RAW_DH_PUBLIC_KEY[2]
|| k[3] != Registry.MAGIC_RAW_DH_PUBLIC_KEY[3]) {
throw new IllegalArgumentException("magic");
}
// version
if (k[4] != 0x01) {
throw new IllegalArgumentException("version");
}
int i = 5;
int l;
byte[] buffer;
// q
l = k[i++] << 24 | (k[i++] & 0xFF) << 16 | (k[i++] & 0xFF) << 8 | (k[i++] & 0xFF);
buffer = new byte[l];
System.arraycopy(k, i, buffer, 0, l);
i += l;
BigInteger q = new BigInteger(1, buffer);
// p
l = k[i++] << 24 | (k[i++] & 0xFF) << 16 | (k[i++] & 0xFF) << 8 | (k[i++] & 0xFF);
buffer = new byte[l];
System.arraycopy(k, i, buffer, 0, l);
i += l;
BigInteger p = new BigInteger(1, buffer);
// g
l = k[i++] << 24 | (k[i++] & 0xFF) << 16 | (k[i++] & 0xFF) << 8 | (k[i++] & 0xFF);
buffer = new byte[l];
System.arraycopy(k, i, buffer, 0, l);
i += l;
BigInteger g = new BigInteger(1, buffer);
// y
l = k[i++] << 24 | (k[i++] & 0xFF) << 16 | (k[i++] & 0xFF) << 8 | (k[i++] & 0xFF);
buffer = new byte[l];
System.arraycopy(k, i, buffer, 0, l);
i += l;
BigInteger y = new BigInteger(1, buffer);
return new GnuDHPublicKey(q, p, g, y);
}
/**
* <p>Returns the encoded form of the designated Diffie-Hellman private key
* according to the <i>Raw</i> format supported by this library.</p>
*
* <p>The <i>Raw</i> format for a DH private key, in this implementation, is
* a byte sequence consisting of the following:</p>
*
* <ol>
* <li>4-byte magic consisting of the value of the literal
* {@link Registry#MAGIC_RAW_DH_PRIVATE_KEY},<li>
* <li>1-byte version consisting of the constant: 0x01,</li>
* <li>4-byte count of following bytes representing the DH parameter
* <code>q</code>,</li>
* <li>n-bytes representation of a {@link BigInteger} obtained by invoking
* the <code>toByteArray()</code> method on the DH parameter <code>q</code>,</li>
* <li>4-byte count of following bytes representing the DH parameter
* <code>p</code> in internet order,</li>
* <li>n-bytes representation of a {@link BigInteger} obtained by invoking
* the <code>toByteArray()</code> method on the DH parameter <code>p</code>,</li>
* <li>4-byte count of following bytes representing the DH parameter
* <code>g</code>,</li>
* <li>n-bytes representation of a {@link BigInteger} obtained by invoking
* the <code>toByteArray()</code> method on the DH parameter <code>g</code>,</li>
* <li>4-byte count of following bytes representing the DH parameter
* <code>x</code>,</li>
* <li>n-bytes representation of a {@link BigInteger} obtained by invoking
* the <code>toByteArray()</code> method on the DH parameter <code>x</code>,</li>
* </ol>
*
* @param key the key to encode.
* @return the <i>Raw</i> format encoding of the designated key.
* @throws IllegalArgumentException if the designated key is not a DH one.
* @see Registry#MAGIC_RAW_DH_PRIVATE_KEY
*/
public byte[] encodePrivateKey(PrivateKey key) {
if (!(key instanceof GnuDHPrivateKey)) {
throw new IllegalArgumentException("key");
}
GnuDHPrivateKey dhKey = (GnuDHPrivateKey) key;
ByteArrayOutputStream baos = new ByteArrayOutputStream();
// magic
baos.write(Registry.MAGIC_RAW_DH_PRIVATE_KEY[0]);
baos.write(Registry.MAGIC_RAW_DH_PRIVATE_KEY[1]);
baos.write(Registry.MAGIC_RAW_DH_PRIVATE_KEY[2]);
baos.write(Registry.MAGIC_RAW_DH_PRIVATE_KEY[3]);
// version
baos.write(0x01);
// q
byte[] buffer = dhKey.getQ().toByteArray();
int length = buffer.length;
baos.write( length >>> 24 );
baos.write((length >>> 16) & 0xFF);
baos.write((length >>> 8) & 0xFF);
baos.write( length & 0xFF);
baos.write(buffer, 0, length);
// p
buffer = dhKey.getParams().getP().toByteArray();
length = buffer.length;
baos.write( length >>> 24 );
baos.write((length >>> 16) & 0xFF);
baos.write((length >>> 8) & 0xFF);
baos.write( length & 0xFF);
baos.write(buffer, 0, length);
// g
buffer = dhKey.getParams().getG().toByteArray();
length = buffer.length;
baos.write( length >>> 24 );
baos.write((length >>> 16) & 0xFF);
baos.write((length >>> 8) & 0xFF);
baos.write( length & 0xFF);
baos.write(buffer, 0, length);
// x
buffer = dhKey.getX().toByteArray();
length = buffer.length;
baos.write( length >>> 24 );
baos.write((length >>> 16) & 0xFF);
baos.write((length >>> 8) & 0xFF);
baos.write( length & 0xFF);
baos.write(buffer, 0, length);
return baos.toByteArray();
}
public PrivateKey decodePrivateKey(byte[] k) {
// magic
if (k[0] != Registry.MAGIC_RAW_DH_PRIVATE_KEY[0]
|| k[1] != Registry.MAGIC_RAW_DH_PRIVATE_KEY[1]
|| k[2] != Registry.MAGIC_RAW_DH_PRIVATE_KEY[2]
|| k[3] != Registry.MAGIC_RAW_DH_PRIVATE_KEY[3]) {
throw new IllegalArgumentException("magic");
}
// version
if (k[4] != 0x01) {
throw new IllegalArgumentException("version");
}
int i = 5;
int l;
byte[] buffer;
// q
l = k[i++] << 24 | (k[i++] & 0xFF) << 16 | (k[i++] & 0xFF) << 8 | (k[i++] & 0xFF);
buffer = new byte[l];
System.arraycopy(k, i, buffer, 0, l);
i += l;
BigInteger q = new BigInteger(1, buffer);
// p
l = k[i++] << 24 | (k[i++] & 0xFF) << 16 | (k[i++] & 0xFF) << 8 | (k[i++] & 0xFF);
buffer = new byte[l];
System.arraycopy(k, i, buffer, 0, l);
i += l;
BigInteger p = new BigInteger(1, buffer);
// g
l = k[i++] << 24 | (k[i++] & 0xFF) << 16 | (k[i++] & 0xFF) << 8 | (k[i++] & 0xFF);
buffer = new byte[l];
System.arraycopy(k, i, buffer, 0, l);
i += l;
BigInteger g = new BigInteger(1, buffer);
// x
l = k[i++] << 24 | (k[i++] & 0xFF) << 16 | (k[i++] & 0xFF) << 8 | (k[i++] & 0xFF);
buffer = new byte[l];
System.arraycopy(k, i, buffer, 0, l);
i += l;
BigInteger x = new BigInteger(1, buffer);
return new GnuDHPrivateKey(q, p, g, x);
}
}