0N/A/*
3909N/A * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved.
0N/A * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
0N/A *
0N/A * This code is free software; you can redistribute it and/or modify it
0N/A * under the terms of the GNU General Public License version 2 only, as
2362N/A * published by the Free Software Foundation. Oracle designates this
0N/A * particular file as subject to the "Classpath" exception as provided
2362N/A * by Oracle in the LICENSE file that accompanied this code.
0N/A *
0N/A * This code is distributed in the hope that it will be useful, but WITHOUT
0N/A * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
0N/A * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
0N/A * version 2 for more details (a copy is included in the LICENSE file that
0N/A * accompanied this code).
0N/A *
0N/A * You should have received a copy of the GNU General Public License version
0N/A * 2 along with this work; if not, write to the Free Software Foundation,
0N/A * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
0N/A *
2362N/A * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
2362N/A * or visit www.oracle.com if you need additional information or have any
2362N/A * questions.
0N/A */
0N/A
0N/Apackage java.security;
0N/A
0N/Aimport java.util.*;
0N/A
0N/Aimport java.security.Provider.Service;
0N/Aimport java.security.spec.KeySpec;
0N/Aimport java.security.spec.InvalidKeySpecException;
0N/A
0N/Aimport sun.security.util.Debug;
0N/Aimport sun.security.jca.*;
0N/Aimport sun.security.jca.GetInstance.Instance;
0N/A
0N/A/**
0N/A * Key factories are used to convert <I>keys</I> (opaque
0N/A * cryptographic keys of type <code>Key</code>) into <I>key specifications</I>
0N/A * (transparent representations of the underlying key material), and vice
0N/A * versa.
0N/A *
0N/A * <P> Key factories are bi-directional. That is, they allow you to build an
0N/A * opaque key object from a given key specification (key material), or to
0N/A * retrieve the underlying key material of a key object in a suitable format.
0N/A *
0N/A * <P> Multiple compatible key specifications may exist for the same key.
0N/A * For example, a DSA public key may be specified using
0N/A * <code>DSAPublicKeySpec</code> or
0N/A * <code>X509EncodedKeySpec</code>. A key factory can be used to translate
0N/A * between compatible key specifications.
0N/A *
0N/A * <P> The following is an example of how to use a key factory in order to
0N/A * instantiate a DSA public key from its encoding.
0N/A * Assume Alice has received a digital signature from Bob.
0N/A * Bob also sent her his public key (in encoded format) to verify
0N/A * his signature. Alice then performs the following actions:
0N/A *
0N/A * <pre>
0N/A * X509EncodedKeySpec bobPubKeySpec = new X509EncodedKeySpec(bobEncodedPubKey);
0N/A * KeyFactory keyFactory = KeyFactory.getInstance("DSA");
0N/A * PublicKey bobPubKey = keyFactory.generatePublic(bobPubKeySpec);
0N/A * Signature sig = Signature.getInstance("DSA");
0N/A * sig.initVerify(bobPubKey);
0N/A * sig.update(data);
0N/A * sig.verify(signature);
0N/A * </pre>
0N/A *
3465N/A * <p> Every implementation of the Java platform is required to support the
3465N/A * following standard <code>KeyFactory</code> algorithms:
3465N/A * <ul>
3465N/A * <li><tt>DiffieHellman</tt></li>
3465N/A * <li><tt>DSA</tt></li>
3465N/A * <li><tt>RSA</tt></li>
3465N/A * </ul>
3465N/A * These algorithms are described in the <a href=
3465N/A * "{@docRoot}/../technotes/guides/security/StandardNames.html#KeyFactory">
3465N/A * KeyFactory section</a> of the
3465N/A * Java Cryptography Architecture Standard Algorithm Name Documentation.
3465N/A * Consult the release documentation for your implementation to see if any
3465N/A * other algorithms are supported.
3465N/A *
0N/A * @author Jan Luehe
0N/A *
0N/A * @see Key
0N/A * @see PublicKey
0N/A * @see PrivateKey
0N/A * @see java.security.spec.KeySpec
0N/A * @see java.security.spec.DSAPublicKeySpec
0N/A * @see java.security.spec.X509EncodedKeySpec
0N/A *
0N/A * @since 1.2
0N/A */
0N/A
0N/Apublic class KeyFactory {
0N/A
0N/A private static final Debug debug =
0N/A Debug.getInstance("jca", "KeyFactory");
0N/A
0N/A // The algorithm associated with this key factory
0N/A private final String algorithm;
0N/A
0N/A // The provider
0N/A private Provider provider;
0N/A
0N/A // The provider implementation (delegate)
0N/A private volatile KeyFactorySpi spi;
0N/A
0N/A // lock for mutex during provider selection
0N/A private final Object lock = new Object();
0N/A
0N/A // remaining services to try in provider selection
0N/A // null once provider is selected
0N/A private Iterator<Service> serviceIterator;
0N/A
0N/A /**
0N/A * Creates a KeyFactory object.
0N/A *
0N/A * @param keyFacSpi the delegate
0N/A * @param provider the provider
0N/A * @param algorithm the name of the algorithm
0N/A * to associate with this <tt>KeyFactory</tt>
0N/A */
0N/A protected KeyFactory(KeyFactorySpi keyFacSpi, Provider provider,
0N/A String algorithm) {
0N/A this.spi = keyFacSpi;
0N/A this.provider = provider;
0N/A this.algorithm = algorithm;
0N/A }
0N/A
0N/A private KeyFactory(String algorithm) throws NoSuchAlgorithmException {
0N/A this.algorithm = algorithm;
0N/A List<Service> list = GetInstance.getServices("KeyFactory", algorithm);
0N/A serviceIterator = list.iterator();
0N/A // fetch and instantiate initial spi
0N/A if (nextSpi(null) == null) {
0N/A throw new NoSuchAlgorithmException
0N/A (algorithm + " KeyFactory not available");
0N/A }
0N/A }
0N/A
0N/A /**
0N/A * Returns a KeyFactory object that converts
0N/A * public/private keys of the specified algorithm.
0N/A *
0N/A * <p> This method traverses the list of registered security Providers,
0N/A * starting with the most preferred Provider.
0N/A * A new KeyFactory object encapsulating the
0N/A * KeyFactorySpi implementation from the first
0N/A * Provider that supports the specified algorithm is returned.
0N/A *
0N/A * <p> Note that the list of registered providers may be retrieved via
0N/A * the {@link Security#getProviders() Security.getProviders()} method.
0N/A *
0N/A * @param algorithm the name of the requested key algorithm.
3465N/A * See the KeyFactory section in the <a href=
3465N/A * "{@docRoot}/../technotes/guides/security/StandardNames.html#KeyFactory">
3465N/A * Java Cryptography Architecture Standard Algorithm Name Documentation</a>
0N/A * for information about standard algorithm names.
0N/A *
0N/A * @return the new KeyFactory object.
0N/A *
0N/A * @exception NoSuchAlgorithmException if no Provider supports a
0N/A * KeyFactorySpi implementation for the
0N/A * specified algorithm.
0N/A *
0N/A * @see Provider
0N/A */
0N/A public static KeyFactory getInstance(String algorithm)
0N/A throws NoSuchAlgorithmException {
0N/A return new KeyFactory(algorithm);
0N/A }
0N/A
0N/A /**
0N/A * Returns a KeyFactory object that converts
0N/A * public/private keys of the specified algorithm.
0N/A *
0N/A * <p> A new KeyFactory object encapsulating the
0N/A * KeyFactorySpi implementation from the specified provider
0N/A * is returned. The specified provider must be registered
0N/A * in the security provider list.
0N/A *
0N/A * <p> Note that the list of registered providers may be retrieved via
0N/A * the {@link Security#getProviders() Security.getProviders()} method.
0N/A *
0N/A * @param algorithm the name of the requested key algorithm.
3465N/A * See the KeyFactory section in the <a href=
3465N/A * "{@docRoot}/../technotes/guides/security/StandardNames.html#KeyFactory">
3465N/A * Java Cryptography Architecture Standard Algorithm Name Documentation</a>
0N/A * for information about standard algorithm names.
0N/A *
0N/A * @param provider the name of the provider.
0N/A *
0N/A * @return the new KeyFactory object.
0N/A *
0N/A * @exception NoSuchAlgorithmException if a KeyFactorySpi
0N/A * implementation for the specified algorithm is not
0N/A * available from the specified provider.
0N/A *
0N/A * @exception NoSuchProviderException if the specified provider is not
0N/A * registered in the security provider list.
0N/A *
0N/A * @exception IllegalArgumentException if the provider name is null
0N/A * or empty.
0N/A *
0N/A * @see Provider
0N/A */
0N/A public static KeyFactory getInstance(String algorithm, String provider)
0N/A throws NoSuchAlgorithmException, NoSuchProviderException {
0N/A Instance instance = GetInstance.getInstance("KeyFactory",
0N/A KeyFactorySpi.class, algorithm, provider);
0N/A return new KeyFactory((KeyFactorySpi)instance.impl,
0N/A instance.provider, algorithm);
0N/A }
0N/A
0N/A /**
0N/A * Returns a KeyFactory object that converts
0N/A * public/private keys of the specified algorithm.
0N/A *
0N/A * <p> A new KeyFactory object encapsulating the
0N/A * KeyFactorySpi implementation from the specified Provider
0N/A * object is returned. Note that the specified Provider object
0N/A * does not have to be registered in the provider list.
0N/A *
0N/A * @param algorithm the name of the requested key algorithm.
3465N/A * See the KeyFactory section in the <a href=
3465N/A * "{@docRoot}/../technotes/guides/security/StandardNames.html#KeyFactory">
3465N/A * Java Cryptography Architecture Standard Algorithm Name Documentation</a>
0N/A * for information about standard algorithm names.
0N/A *
0N/A * @param provider the provider.
0N/A *
0N/A * @return the new KeyFactory object.
0N/A *
0N/A * @exception NoSuchAlgorithmException if a KeyFactorySpi
0N/A * implementation for the specified algorithm is not available
0N/A * from the specified Provider object.
0N/A *
0N/A * @exception IllegalArgumentException if the specified provider is null.
0N/A *
0N/A * @see Provider
0N/A *
0N/A * @since 1.4
0N/A */
0N/A public static KeyFactory getInstance(String algorithm, Provider provider)
0N/A throws NoSuchAlgorithmException {
0N/A Instance instance = GetInstance.getInstance("KeyFactory",
0N/A KeyFactorySpi.class, algorithm, provider);
0N/A return new KeyFactory((KeyFactorySpi)instance.impl,
0N/A instance.provider, algorithm);
0N/A }
0N/A
0N/A /**
0N/A * Returns the provider of this key factory object.
0N/A *
0N/A * @return the provider of this key factory object
0N/A */
0N/A public final Provider getProvider() {
0N/A synchronized (lock) {
0N/A // disable further failover after this call
0N/A serviceIterator = null;
0N/A return provider;
0N/A }
0N/A }
0N/A
0N/A /**
0N/A * Gets the name of the algorithm
0N/A * associated with this <tt>KeyFactory</tt>.
0N/A *
0N/A * @return the name of the algorithm associated with this
0N/A * <tt>KeyFactory</tt>
0N/A */
0N/A public final String getAlgorithm() {
0N/A return this.algorithm;
0N/A }
0N/A
0N/A /**
0N/A * Update the active KeyFactorySpi of this class and return the next
0N/A * implementation for failover. If no more implemenations are
0N/A * available, this method returns null. However, the active spi of
0N/A * this class is never set to null.
0N/A */
0N/A private KeyFactorySpi nextSpi(KeyFactorySpi oldSpi) {
0N/A synchronized (lock) {
0N/A // somebody else did a failover concurrently
0N/A // try that spi now
0N/A if ((oldSpi != null) && (oldSpi != spi)) {
0N/A return spi;
0N/A }
0N/A if (serviceIterator == null) {
0N/A return null;
0N/A }
0N/A while (serviceIterator.hasNext()) {
0N/A Service s = serviceIterator.next();
0N/A try {
0N/A Object obj = s.newInstance(null);
0N/A if (obj instanceof KeyFactorySpi == false) {
0N/A continue;
0N/A }
0N/A KeyFactorySpi spi = (KeyFactorySpi)obj;
0N/A provider = s.getProvider();
0N/A this.spi = spi;
0N/A return spi;
0N/A } catch (NoSuchAlgorithmException e) {
0N/A // ignore
0N/A }
0N/A }
0N/A serviceIterator = null;
0N/A return null;
0N/A }
0N/A }
0N/A
0N/A /**
0N/A * Generates a public key object from the provided key specification
0N/A * (key material).
0N/A *
0N/A * @param keySpec the specification (key material) of the public key.
0N/A *
0N/A * @return the public key.
0N/A *
0N/A * @exception InvalidKeySpecException if the given key specification
0N/A * is inappropriate for this key factory to produce a public key.
0N/A */
0N/A public final PublicKey generatePublic(KeySpec keySpec)
0N/A throws InvalidKeySpecException {
0N/A if (serviceIterator == null) {
0N/A return spi.engineGeneratePublic(keySpec);
0N/A }
0N/A Exception failure = null;
0N/A KeyFactorySpi mySpi = spi;
0N/A do {
0N/A try {
0N/A return mySpi.engineGeneratePublic(keySpec);
0N/A } catch (Exception e) {
0N/A if (failure == null) {
0N/A failure = e;
0N/A }
0N/A mySpi = nextSpi(mySpi);
0N/A }
0N/A } while (mySpi != null);
0N/A if (failure instanceof RuntimeException) {
0N/A throw (RuntimeException)failure;
0N/A }
0N/A if (failure instanceof InvalidKeySpecException) {
0N/A throw (InvalidKeySpecException)failure;
0N/A }
0N/A throw new InvalidKeySpecException
0N/A ("Could not generate public key", failure);
0N/A }
0N/A
0N/A /**
0N/A * Generates a private key object from the provided key specification
0N/A * (key material).
0N/A *
0N/A * @param keySpec the specification (key material) of the private key.
0N/A *
0N/A * @return the private key.
0N/A *
0N/A * @exception InvalidKeySpecException if the given key specification
0N/A * is inappropriate for this key factory to produce a private key.
0N/A */
0N/A public final PrivateKey generatePrivate(KeySpec keySpec)
0N/A throws InvalidKeySpecException {
0N/A if (serviceIterator == null) {
0N/A return spi.engineGeneratePrivate(keySpec);
0N/A }
0N/A Exception failure = null;
0N/A KeyFactorySpi mySpi = spi;
0N/A do {
0N/A try {
0N/A return mySpi.engineGeneratePrivate(keySpec);
0N/A } catch (Exception e) {
0N/A if (failure == null) {
0N/A failure = e;
0N/A }
0N/A mySpi = nextSpi(mySpi);
0N/A }
0N/A } while (mySpi != null);
0N/A if (failure instanceof RuntimeException) {
0N/A throw (RuntimeException)failure;
0N/A }
0N/A if (failure instanceof InvalidKeySpecException) {
0N/A throw (InvalidKeySpecException)failure;
0N/A }
0N/A throw new InvalidKeySpecException
0N/A ("Could not generate private key", failure);
0N/A }
0N/A
0N/A /**
0N/A * Returns a specification (key material) of the given key object.
0N/A * <code>keySpec</code> identifies the specification class in which
0N/A * the key material should be returned. It could, for example, be
0N/A * <code>DSAPublicKeySpec.class</code>, to indicate that the
0N/A * key material should be returned in an instance of the
0N/A * <code>DSAPublicKeySpec</code> class.
0N/A *
0N/A * @param key the key.
0N/A *
0N/A * @param keySpec the specification class in which
0N/A * the key material should be returned.
0N/A *
0N/A * @return the underlying key specification (key material) in an instance
0N/A * of the requested specification class.
0N/A *
0N/A * @exception InvalidKeySpecException if the requested key specification is
0N/A * inappropriate for the given key, or the given key cannot be processed
0N/A * (e.g., the given key has an unrecognized algorithm or format).
0N/A */
0N/A public final <T extends KeySpec> T getKeySpec(Key key, Class<T> keySpec)
0N/A throws InvalidKeySpecException {
0N/A if (serviceIterator == null) {
0N/A return spi.engineGetKeySpec(key, keySpec);
0N/A }
0N/A Exception failure = null;
0N/A KeyFactorySpi mySpi = spi;
0N/A do {
0N/A try {
0N/A return mySpi.engineGetKeySpec(key, keySpec);
0N/A } catch (Exception e) {
0N/A if (failure == null) {
0N/A failure = e;
0N/A }
0N/A mySpi = nextSpi(mySpi);
0N/A }
0N/A } while (mySpi != null);
0N/A if (failure instanceof RuntimeException) {
0N/A throw (RuntimeException)failure;
0N/A }
0N/A if (failure instanceof InvalidKeySpecException) {
0N/A throw (InvalidKeySpecException)failure;
0N/A }
0N/A throw new InvalidKeySpecException
0N/A ("Could not get key spec", failure);
0N/A }
0N/A
0N/A /**
0N/A * Translates a key object, whose provider may be unknown or potentially
0N/A * untrusted, into a corresponding key object of this key factory.
0N/A *
0N/A * @param key the key whose provider is unknown or untrusted.
0N/A *
0N/A * @return the translated key.
0N/A *
0N/A * @exception InvalidKeyException if the given key cannot be processed
0N/A * by this key factory.
0N/A */
0N/A public final Key translateKey(Key key) throws InvalidKeyException {
0N/A if (serviceIterator == null) {
0N/A return spi.engineTranslateKey(key);
0N/A }
0N/A Exception failure = null;
0N/A KeyFactorySpi mySpi = spi;
0N/A do {
0N/A try {
0N/A return mySpi.engineTranslateKey(key);
0N/A } catch (Exception e) {
0N/A if (failure == null) {
0N/A failure = e;
0N/A }
0N/A mySpi = nextSpi(mySpi);
0N/A }
0N/A } while (mySpi != null);
0N/A if (failure instanceof RuntimeException) {
0N/A throw (RuntimeException)failure;
0N/A }
0N/A if (failure instanceof InvalidKeyException) {
0N/A throw (InvalidKeyException)failure;
0N/A }
0N/A throw new InvalidKeyException
0N/A ("Could not translate key", failure);
0N/A }
0N/A
0N/A}