/*
* Copyright 2003-2007 Sun Microsystems, Inc. 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. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
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*/
package com.sun.crypto.provider;
import java.security.*;
import java.security.spec.AlgorithmParameterSpec;
import javax.crypto.*;
import javax.crypto.spec.SecretKeySpec;
/**
* KeyGeneratore core implementation and individual key generator
* implementations. Because of US export regulations, we cannot use
* subclassing to achieve code sharing between the key generator
* implementations for our various algorithms. Instead, we have the
* core implementation in this KeyGeneratorCore class, which is used
* by the individual implementations. See those further down in this
* file.
*
* @since 1.5
* @author Andreas Sterbenz
*/
final class KeyGeneratorCore {
// algorithm name to use for the generator keys
private final String name;
// default key size in bits
private final int defaultKeySize;
// current key size in bits
private int keySize;
// PRNG to use
private SecureRandom random;
/**
* Construct a new KeyGeneratorCore object with the specified name
* and defaultKeySize. Initialize to default key size in case the
* application does not call any of the init() methods.
*/
KeyGeneratorCore(String name, int defaultKeySize) {
this.name = name;
this.defaultKeySize = defaultKeySize;
implInit(null);
}
// implementation for engineInit(), see JCE doc
// reset keySize to default
void implInit(SecureRandom random) {
this.keySize = defaultKeySize;
this.random = random;
}
// implementation for engineInit(), see JCE doc
// we do not support any parameters
void implInit(AlgorithmParameterSpec params, SecureRandom random)
throws InvalidAlgorithmParameterException {
throw new InvalidAlgorithmParameterException
(name + " key generation does not take any parameters");
}
// implementation for engineInit(), see JCE doc
// we enforce a general 40 bit minimum key size for security
void implInit(int keysize, SecureRandom random) {
if (keysize < 40) {
throw new InvalidParameterException
("Key length must be at least 40 bits");
}
this.keySize = keysize;
this.random = random;
}
// implementation for engineInit(), see JCE doc
// generate the key
SecretKey implGenerateKey() {
if (random == null) {
random = SunJCE.RANDOM;
}
byte[] b = new byte[(keySize + 7) >> 3];
random.nextBytes(b);
return new SecretKeySpec(b, name);
}
// nested static class for the HmacSHA256 key generator
public static final class HmacSHA256KG extends KeyGeneratorSpi {
private final KeyGeneratorCore core;
public HmacSHA256KG() {
SunJCE.ensureIntegrity(getClass());
core = new KeyGeneratorCore("HmacSHA256", 256);
}
protected void engineInit(SecureRandom random) {
core.implInit(random);
}
protected void engineInit(AlgorithmParameterSpec params,
SecureRandom random) throws InvalidAlgorithmParameterException {
core.implInit(params, random);
}
protected void engineInit(int keySize, SecureRandom random) {
core.implInit(keySize, random);
}
protected SecretKey engineGenerateKey() {
return core.implGenerateKey();
}
}
// nested static class for the HmacSHA384 key generator
public static final class HmacSHA384KG extends KeyGeneratorSpi {
private final KeyGeneratorCore core;
public HmacSHA384KG() {
SunJCE.ensureIntegrity(getClass());
core = new KeyGeneratorCore("HmacSHA384", 384);
}
protected void engineInit(SecureRandom random) {
core.implInit(random);
}
protected void engineInit(AlgorithmParameterSpec params,
SecureRandom random) throws InvalidAlgorithmParameterException {
core.implInit(params, random);
}
protected void engineInit(int keySize, SecureRandom random) {
core.implInit(keySize, random);
}
protected SecretKey engineGenerateKey() {
return core.implGenerateKey();
}
}
// nested static class for the HmacSHA384 key generator
public static final class HmacSHA512KG extends KeyGeneratorSpi {
private final KeyGeneratorCore core;
public HmacSHA512KG() {
SunJCE.ensureIntegrity(getClass());
core = new KeyGeneratorCore("HmacSHA512", 512);
}
protected void engineInit(SecureRandom random) {
core.implInit(random);
}
protected void engineInit(AlgorithmParameterSpec params,
SecureRandom random) throws InvalidAlgorithmParameterException {
core.implInit(params, random);
}
protected void engineInit(int keySize, SecureRandom random) {
core.implInit(keySize, random);
}
protected SecretKey engineGenerateKey() {
return core.implGenerateKey();
}
}
// nested static class for the RC2 key generator
public static final class RC2KeyGenerator extends KeyGeneratorSpi {
private final KeyGeneratorCore core;
public RC2KeyGenerator() {
SunJCE.ensureIntegrity(getClass());
core = new KeyGeneratorCore("RC2", 128);
}
protected void engineInit(SecureRandom random) {
core.implInit(random);
}
protected void engineInit(AlgorithmParameterSpec params,
SecureRandom random) throws InvalidAlgorithmParameterException {
core.implInit(params, random);
}
protected void engineInit(int keySize, SecureRandom random) {
if ((keySize < 40) || (keySize > 1024)) {
throw new InvalidParameterException("Key length for RC2"
+ " must be between 40 and 1024 bits");
}
core.implInit(keySize, random);
}
protected SecretKey engineGenerateKey() {
return core.implGenerateKey();
}
}
// nested static class for the ARCFOUR (RC4) key generator
public static final class ARCFOURKeyGenerator extends KeyGeneratorSpi {
private final KeyGeneratorCore core;
public ARCFOURKeyGenerator() {
SunJCE.ensureIntegrity(getClass());
core = new KeyGeneratorCore("ARCFOUR", 128);
}
protected void engineInit(SecureRandom random) {
core.implInit(random);
}
protected void engineInit(AlgorithmParameterSpec params,
SecureRandom random) throws InvalidAlgorithmParameterException {
core.implInit(params, random);
}
protected void engineInit(int keySize, SecureRandom random) {
if ((keySize < 40) || (keySize > 1024)) {
throw new InvalidParameterException("Key length for ARCFOUR"
+ " must be between 40 and 1024 bits");
}
core.implInit(keySize, random);
}
protected SecretKey engineGenerateKey() {
return core.implGenerateKey();
}
}
}