/*
* Copyright (c) 2002-2010 Atsuhiko Yamanaka, JCraft,Inc. All rights reserved.
* Copyright (c) 2010-2011 Michael Laudati, N1 Concepts LLC.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* 3. The names of the authors may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JCRAFT,
* INC. OR ANY CONTRIBUTORS TO THIS SOFTWARE BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
* OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package org.vngx.jsch.util;
import org.vngx.jsch.algorithm.KeyPairGenDSA;
import org.vngx.jsch.Buffer;
import org.vngx.jsch.Util;
import org.vngx.jsch.config.JSchConfig;
import org.vngx.jsch.algorithm.Algorithms;
import org.vngx.jsch.exception.JSchException;
/**
* Implementation of <code>KeyPair</code> for generating a public/private key
* pair using DSA encryption.
*
* @author Atsuhiko Yamanaka
* @author Michael Laudati
*/
public class KeyPairDSA extends KeyPair {
/** Constant begin line for DSA private key file. */
private static final byte[] BEGIN = Util.str2byte("-----BEGIN DSA PRIVATE KEY-----");
/** Constant end line for DSA private key file. */
private static final byte[] END = Util.str2byte("-----END DSA PRIVATE KEY-----");
/** Key size to generate. */
private int _keySize = 1024;
/** Public key data */
private byte[] _pubKey;
/** Private key data */
private byte[] _prvKey;
/** DSA prime modulus 'p'. */
private byte[] _p;
/** DSA prime number 'q'. */
private byte[] _q;
/** DSA number whose multiplicative order modulo p is q. */
private byte[] _g;
/**
* Creates a new instance of <code>KeyPairDSA</code>.
*/
public KeyPairDSA() { }
@Override
void generate(int keySize) throws JSchException {
try {
KeyPairGenDSA keypairgen = JSchConfig.getConfig().getClassImpl(Algorithms.KEYPAIRGEN_DSA);
keypairgen.init(_keySize = keySize); // Initialize generator with key size
_pubKey = keypairgen.getY();
_prvKey = keypairgen.getX();
_p = keypairgen.getP();
_q = keypairgen.getQ();
_g = keypairgen.getG();
} catch(Exception e) {
throw new JSchException("Failed to generate KeyPairDSA: "+e, e);
}
}
@Override
byte[] getBegin() {
return BEGIN;
}
@Override
byte[] getEnd() {
return END;
}
@Override
byte[] getPrivateKey() {
int content =
1 + DataUtil.countLength(1) + 1 + // INTEGER
1 + DataUtil.countLength(_p.length) + _p.length + // INTEGER P
1 + DataUtil.countLength(_q.length) + _q.length + // INTEGER Q
1 + DataUtil.countLength(_g.length) + _g.length + // INTEGER G
1 + DataUtil.countLength(_pubKey.length) + _pubKey.length + // INTEGER pub
1 + DataUtil.countLength(_prvKey.length) + _prvKey.length; // INTEGER prv
int total = 1 + DataUtil.countLength(content) + content; // SEQUENCE
byte[] plain = new byte[total];
int index = 0;
index = DataUtil.writeSEQUENCE(plain, index, content);
index = DataUtil.writeINTEGER(plain, index, new byte[1]); // 0
index = DataUtil.writeINTEGER(plain, index, _p);
index = DataUtil.writeINTEGER(plain, index, _q);
index = DataUtil.writeINTEGER(plain, index, _g);
index = DataUtil.writeINTEGER(plain, index, _pubKey);
index = DataUtil.writeINTEGER(plain, index, _prvKey);
return plain;
}
@Override
boolean parse(byte[] plain) {
try {
if( _vendor == VENDOR_FSECURE ) {
if( plain[0] != 0x30 ) { // FSecure
Buffer buf = new Buffer(plain);
buf.getInt();
_p = buf.getMPIntBits();
_g = buf.getMPIntBits();
_q = buf.getMPIntBits();
_pubKey = buf.getMPIntBits();
_prvKey = buf.getMPIntBits();
return true;
}
return false;
}
int[] index = new int[1];
int length = 0;
if( plain[index[0]] != 0x30 ) { // Zero '0'
return false;
}
index[0]++; // SEQUENCE
length = plain[index[0]++] & 0xff;
if( (length & 0x80) != 0 ) {
int foo = length & 0x7f;
length = 0;
while( foo-- > 0 ) {
length = (length << 8) + (plain[index[0]++] & 0xff);
}
}
if( plain[index[0]] != 0x02 ) { // STX (start of text)
return false;
}
DataUtil.readINTEGER(index, plain);
_p = DataUtil.readINTEGER(index, plain);
_q = DataUtil.readINTEGER(index, plain);
_g = DataUtil.readINTEGER(index, plain);
_pubKey = DataUtil.readINTEGER(index, plain);
_prvKey = DataUtil.readINTEGER(index, plain);
} catch(Exception e) {
// TODO Error handling?
return false;
}
return true;
}
@Override
public byte[] getPublicKeyBlob() {
byte[] pubKeyBlob = super.getPublicKeyBlob();
if( pubKeyBlob != null ) {
return pubKeyBlob;
} else if( _p == null ) {
return null;
}
byte[] buffer = new byte[KeyType.SSH_DSS.toString().length() + 4 + _p.length + 4 +
_q.length + 4 + _g.length + 4 + _pubKey.length + 4];
Buffer buf = new Buffer(buffer);
buf.putString(KeyType.SSH_DSS.getBytes());
buf.putString(_p);
buf.putString(_q);
buf.putString(_g);
buf.putString(_pubKey);
return buffer;
}
@Override
byte[] getKeyTypeName() {
return KeyType.SSH_DSS.getBytes();
}
@Override
int getKeySize() {
return _keySize;
}
@Override
public KeyType getKeyType() {
return KeyType.SSH_DSS;
}
@Override
public void dispose() {
super.dispose();
Util.bzero(_prvKey);
}
}