/*
* Copyright (c) 1996, 2005, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code 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
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package sun.security.provider;
import java.util.*;
import java.io.*;
import java.math.BigInteger;
import java.security.InvalidKeyException;
import java.security.ProviderException;
import java.security.AlgorithmParameters;
import java.security.spec.DSAParameterSpec;
import java.security.spec.InvalidParameterSpecException;
import java.security.interfaces.DSAParams;
import sun.security.x509.X509Key;
import sun.security.x509.AlgIdDSA;
import sun.security.util.Debug;
import sun.security.util.DerValue;
import sun.security.util.DerInputStream;
import sun.security.util.DerOutputStream;
/**
* An X.509 public key for the Digital Signature Algorithm.
*
* @author Benjamin Renaud
*
*
* @see DSAPrivateKey
* @see AlgIdDSA
* @see DSA
*/
public class DSAPublicKey extends X509Key
implements java.security.interfaces.DSAPublicKey, Serializable {
/** use serialVersionUID from JDK 1.1. for interoperability */
private static final long serialVersionUID = -2994193307391104133L;
/* the public key */
private BigInteger y;
/*
* Keep this constructor for backwards compatibility with JDK1.1.
*/
public DSAPublicKey() {
}
/**
* Make a DSA public key out of a public key and three parameters.
* The p, q, and g parameters may be null, but if so, parameters will need
* to be supplied from some other source before this key can be used in
* cryptographic operations. PKIX RFC2459bis explicitly allows DSA public
* keys without parameters, where the parameters are provided in the
* issuer's DSA public key.
*
* @param y the actual key bits
* @param p DSA parameter p, may be null if all of p, q, and g are null.
* @param q DSA parameter q, may be null if all of p, q, and g are null.
* @param g DSA parameter g, may be null if all of p, q, and g are null.
*/
public DSAPublicKey(BigInteger y, BigInteger p, BigInteger q,
BigInteger g)
throws InvalidKeyException {
this.y = y;
algid = new AlgIdDSA(p, q, g);
try {
key = new DerValue(DerValue.tag_Integer,
y.toByteArray()).toByteArray();
encode();
} catch (IOException e) {
throw new InvalidKeyException("could not DER encode y: " +
e.getMessage());
}
}
/**
* Make a DSA public key from its DER encoding (X.509).
*/
public DSAPublicKey(byte[] encoded) throws InvalidKeyException {
decode(encoded);
}
/**
* Returns the DSA parameters associated with this key, or null if the
* parameters could not be parsed.
*/
public DSAParams getParams() {
try {
if (algid instanceof DSAParams) {
return (DSAParams)algid;
} else {
DSAParameterSpec paramSpec;
AlgorithmParameters algParams = algid.getParameters();
if (algParams == null) {
return null;
}
paramSpec = algParams.getParameterSpec(DSAParameterSpec.class);
return (DSAParams)paramSpec;
}
} catch (InvalidParameterSpecException e) {
return null;
}
}
/**
* Get the raw public value, y, without the parameters.
*
* @see getParameters
*/
public BigInteger getY() {
return y;
}
public String toString() {
return "Sun DSA Public Key\n Parameters:" + algid
+ "\n y:\n" + Debug.toHexString(y) + "\n";
}
protected void parseKeyBits() throws InvalidKeyException {
try {
DerInputStream in = new DerInputStream(key);
y = in.getBigInteger();
} catch (IOException e) {
throw new InvalidKeyException("Invalid key: y value\n" +
e.getMessage());
}
}
}