Initial revision
From-SVN: r102074
This commit is contained in:
@@ -0,0 +1,297 @@
|
||||
/* KeyFactory.java --- Key Factory Class
|
||||
Copyright (C) 1999, 2003, 2004 Free Software Foundation, Inc.
|
||||
|
||||
This file is part of GNU Classpath.
|
||||
|
||||
GNU Classpath 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 Classpath 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 GNU Classpath; 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 executable under
|
||||
terms of your choice, provided that you also meet, for each linked
|
||||
independent module, the terms and conditions of the license of that
|
||||
module. An independent module is a module which is not derived from
|
||||
or based on this library. If you modify this 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. */
|
||||
|
||||
|
||||
package java.security;
|
||||
|
||||
import gnu.java.security.Engine;
|
||||
|
||||
import java.security.spec.InvalidKeySpecException;
|
||||
import java.security.spec.KeySpec;
|
||||
|
||||
/**
|
||||
* <p>Key factories are used to convert keys (opaque cryptographic keys of type
|
||||
* {@link Key}) into key specifications (transparent representations of the
|
||||
* underlying key material), and vice versa.</p>
|
||||
*
|
||||
* <p>Key factories are bi-directional. That is, they allow you to build an
|
||||
* opaque key object from a given key specification (key material), or to
|
||||
* retrieve the underlying key material of a key object in a suitable format.</p>
|
||||
*
|
||||
* <p>Multiple compatible key specifications may exist for the same key. For
|
||||
* example, a <i>DSA</i> public key may be specified using {@link
|
||||
* java.security.spec.DSAPublicKeySpec} or {@link
|
||||
* java.security.spec.X509EncodedKeySpec}. A key factory can be used to
|
||||
* translate between compatible key specifications.</p>
|
||||
*
|
||||
* <p>The following is an example of how to use a key factory in order to
|
||||
* instantiate a <i>DSA</i> public key from its encoding. Assume Alice has
|
||||
* received a digital signature from Bob. Bob also sent her his public key (in
|
||||
* encoded format) to verify his signature. Alice then performs the following
|
||||
* actions:
|
||||
*
|
||||
* <pre>
|
||||
* X509EncodedKeySpec bobPubKeySpec = new X509EncodedKeySpec(bobEncodedPubKey);
|
||||
* KeyFactory keyFactory = KeyFactory.getInstance("DSA");
|
||||
* PublicKey bobPubKey = keyFactory.generatePublic(bobPubKeySpec);
|
||||
* Signature sig = Signature.getInstance("DSA");
|
||||
* sig.initVerify(bobPubKey);
|
||||
* sig.update(data);
|
||||
* sig.verify(signature);
|
||||
* </pre>
|
||||
*
|
||||
* @since 1.2
|
||||
* @see Key
|
||||
* @see PublicKey
|
||||
* @see PrivateKey
|
||||
* @see KeySpec
|
||||
* @see java.security.spec.DSAPublicKeySpec
|
||||
* @see java.security.spec.X509EncodedKeySpec
|
||||
@author Mark Benvenuto
|
||||
*/
|
||||
public class KeyFactory
|
||||
{
|
||||
/** The service name for key factories. */
|
||||
private static final String KEY_FACTORY = "KeyFactory";
|
||||
|
||||
private KeyFactorySpi keyFacSpi;
|
||||
private Provider provider;
|
||||
private String algorithm;
|
||||
|
||||
/**
|
||||
* Creates a <code>KeyFactory</code> object.
|
||||
*
|
||||
* @param keyFacSpi the delegate.
|
||||
* @param provider the provider.
|
||||
* @param algorithm the name of the algorithm to associate with this
|
||||
* <code>KeyFactory</code>.
|
||||
*/
|
||||
protected KeyFactory(KeyFactorySpi keyFacSpi, Provider provider,
|
||||
String algorithm)
|
||||
{
|
||||
this.keyFacSpi = keyFacSpi;
|
||||
this.provider = provider;
|
||||
this.algorithm = algorithm;
|
||||
}
|
||||
|
||||
/**
|
||||
* Generates a <code>KeyFactory</code> object that implements the specified
|
||||
* algorithm. If the default provider package provides an implementation of
|
||||
* the requested algorithm, an instance of <code>KeyFactory</code> containing
|
||||
* that implementation is returned. If the algorithm is not available in the
|
||||
* default package, other packages are searched.
|
||||
*
|
||||
* @param algorithm the name of the requested key algorithm. See Appendix A
|
||||
* in the Java Cryptography Architecture API Specification & Reference
|
||||
* for information about standard algorithm names.
|
||||
* @return a <code>KeyFactory</code> object for the specified algorithm.
|
||||
* @throws NoSuchAlgorithmException if the requested algorithm is not
|
||||
* available in the default provider package or any of the other provider
|
||||
* packages that were searched.
|
||||
*/
|
||||
public static KeyFactory getInstance(String algorithm)
|
||||
throws NoSuchAlgorithmException
|
||||
{
|
||||
Provider[] p = Security.getProviders();
|
||||
for (int i = 0; i < p.length; i++)
|
||||
try
|
||||
{
|
||||
return getInstance(algorithm, p[i]);
|
||||
}
|
||||
catch (NoSuchAlgorithmException e)
|
||||
{
|
||||
// Ignore.
|
||||
}
|
||||
|
||||
throw new NoSuchAlgorithmException(algorithm);
|
||||
}
|
||||
|
||||
/**
|
||||
* Generates a <code>KeyFactory</code> object for the specified algorithm
|
||||
* from the specified provider.
|
||||
*
|
||||
* @param algorithm the name of the requested key algorithm. See Appendix A
|
||||
* in the Java Cryptography Architecture API Specification & Reference
|
||||
* for information about standard algorithm names.
|
||||
* @param provider the name of the provider.
|
||||
* @return a <code>KeyFactory</code> object for the specified algorithm.
|
||||
* @throws NoSuchAlgorithmException if the algorithm is not available from
|
||||
* the specified provider.
|
||||
* @throws NoSuchProviderException if the provider has not been configured.
|
||||
* @throws IllegalArgumentException if the provider name is null or empty.
|
||||
* @see Provider
|
||||
*/
|
||||
public static KeyFactory getInstance(String algorithm, String provider)
|
||||
throws NoSuchAlgorithmException, NoSuchProviderException
|
||||
{
|
||||
if (provider == null || provider.length() == 0)
|
||||
throw new IllegalArgumentException("Illegal provider");
|
||||
|
||||
Provider p = Security.getProvider(provider);
|
||||
if (p == null)
|
||||
throw new NoSuchProviderException(provider);
|
||||
|
||||
return getInstance(algorithm, p);
|
||||
}
|
||||
|
||||
/**
|
||||
* Generates a <code>KeyFactory</code> object for the specified algorithm from
|
||||
* the specified provider. Note: the <code>provider</code> doesn't have to be
|
||||
* registered.
|
||||
*
|
||||
* @param algorithm the name of the requested key algorithm. See Appendix A
|
||||
* in the Java Cryptography Architecture API Specification & Reference for
|
||||
* information about standard algorithm names.
|
||||
* @param provider the provider.
|
||||
* @return a <code>KeyFactory</code> object for the specified algorithm.
|
||||
* @throws NoSuchAlgorithmException if the algorithm is not available from
|
||||
* the specified provider.
|
||||
* @throws IllegalArgumentException if the <code>provider</code> is
|
||||
* <code>null</code>.
|
||||
* @since 1.4
|
||||
* @see Provider
|
||||
*/
|
||||
public static KeyFactory getInstance(String algorithm, Provider provider)
|
||||
throws NoSuchAlgorithmException
|
||||
{
|
||||
if (provider == null)
|
||||
throw new IllegalArgumentException("Illegal provider");
|
||||
|
||||
try
|
||||
{
|
||||
return new KeyFactory((KeyFactorySpi)
|
||||
Engine.getInstance(KEY_FACTORY, algorithm, provider),
|
||||
provider, algorithm);
|
||||
}
|
||||
catch (java.lang.reflect.InvocationTargetException ite)
|
||||
{
|
||||
throw new NoSuchAlgorithmException(algorithm);
|
||||
}
|
||||
catch (ClassCastException cce)
|
||||
{
|
||||
throw new NoSuchAlgorithmException(algorithm);
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns the provider of this key factory object.
|
||||
*
|
||||
* @return the provider of this key factory object.
|
||||
*/
|
||||
public final Provider getProvider()
|
||||
{
|
||||
return provider;
|
||||
}
|
||||
|
||||
/**
|
||||
* Gets the name of the algorithm associated with this <code>KeyFactory</code>.
|
||||
*
|
||||
* @return the name of the algorithm associated with this
|
||||
* <code>KeyFactory</code>.
|
||||
*/
|
||||
public final String getAlgorithm()
|
||||
{
|
||||
return algorithm;
|
||||
}
|
||||
|
||||
/**
|
||||
* Generates a public key object from the provided key specification (key
|
||||
* material).
|
||||
*
|
||||
* @param keySpec the specification (key material) of the public key.
|
||||
* @return the public key.
|
||||
* @throws InvalidKeySpecException if the given key specification is
|
||||
* inappropriate for this key factory to produce a public key.
|
||||
*/
|
||||
public final PublicKey generatePublic(KeySpec keySpec)
|
||||
throws InvalidKeySpecException
|
||||
{
|
||||
return keyFacSpi.engineGeneratePublic(keySpec);
|
||||
}
|
||||
|
||||
/**
|
||||
* Generates a private key object from the provided key specification (key
|
||||
* material).
|
||||
*
|
||||
* @param keySpec the specification (key material) of the private key.
|
||||
* @return the private key.
|
||||
* @throws InvalidKeySpecException if the given key specification is
|
||||
* inappropriate for this key factory to produce a private key.
|
||||
*/
|
||||
public final PrivateKey generatePrivate(KeySpec keySpec)
|
||||
throws InvalidKeySpecException
|
||||
{
|
||||
return keyFacSpi.engineGeneratePrivate(keySpec);
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns a specification (key material) of the given key object.
|
||||
* <code>keySpec</code> identifies the specification class in which the key
|
||||
* material should be returned. It could, for example, be
|
||||
* <code>DSAPublicKeySpec.class</code>, to indicate that the key material
|
||||
* should be returned in an instance of the {@link
|
||||
* java.security.spec.DSAPublicKeySpec} class.
|
||||
*
|
||||
* @param key the key.
|
||||
* @param keySpec the specification class in which the key material should be
|
||||
* returned.
|
||||
* @return the underlying key specification (key material) in an instance of
|
||||
* the requested specification class.
|
||||
* @throws InvalidKeySpecException if the requested key specification is
|
||||
* inappropriate for the given key, or the given key cannot be processed
|
||||
* (e.g., the given key has an unrecognized algorithm or format).
|
||||
*/
|
||||
public final KeySpec getKeySpec(Key key, Class keySpec)
|
||||
throws InvalidKeySpecException
|
||||
{
|
||||
return keyFacSpi.engineGetKeySpec(key, keySpec);
|
||||
}
|
||||
|
||||
/**
|
||||
* Translates a key object, whose provider may be unknown or potentially
|
||||
* untrusted, into a corresponding key object of this key factory.
|
||||
*
|
||||
* @param key the key whose provider is unknown or untrusted.
|
||||
* @return the translated key.
|
||||
* @throws InvalidKeyException if the given key cannot be processed by this
|
||||
* key factory.
|
||||
*/
|
||||
public final Key translateKey(Key key) throws InvalidKeyException
|
||||
{
|
||||
return keyFacSpi.engineTranslateKey(key);
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user