244 lines
7.4 KiB
Java
244 lines
7.4 KiB
Java
/* KeyFactory.java --- Key Factory Class
|
|
Copyright (C) 1999 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., 59 Temple Place, Suite 330, Boston, MA
|
|
02111-1307 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 java.security.spec.KeySpec;
|
|
import java.security.spec.InvalidKeySpecException;
|
|
|
|
/**
|
|
Key factories are used to convert keys (opaque cryptographic
|
|
keys of type Key) into key specifications (transparent
|
|
representations of the underlying key material).
|
|
|
|
Key factories are bi-directional. They allow a key class
|
|
to be converted into a key specification (key material) and
|
|
back again.
|
|
|
|
For example DSA public keys can be specified as
|
|
DSAPublicKeySpec or X509EncodedKeySpec. The key factory
|
|
translate these key specifications.
|
|
|
|
@since JDK 1.2
|
|
@author Mark Benvenuto
|
|
*/
|
|
public class KeyFactory
|
|
{
|
|
private KeyFactorySpi keyFacSpi;
|
|
private Provider provider;
|
|
private String algorithm;
|
|
|
|
/**
|
|
Constructs a new keyFactory with the specified parameters.
|
|
|
|
@param keyFacSpi Key Factory SPI to use
|
|
@param provider the provider of the Key Factory SPI
|
|
@param algorithm the name of the key algorithm for this key factory
|
|
*/
|
|
protected KeyFactory(KeyFactorySpi keyFacSpi, Provider provider,
|
|
String algorithm)
|
|
{
|
|
this.keyFacSpi = keyFacSpi;
|
|
this.provider = provider;
|
|
this.algorithm = algorithm;
|
|
}
|
|
|
|
/**
|
|
Gets an instance of the KeyFactory class representing
|
|
the specified key factory. If the algorithm is not
|
|
found then, it throws NoSuchAlgorithmException.
|
|
|
|
@param algorithm the name of algorithm to choose
|
|
@return a KeyFactory repesenting the desired algorithm
|
|
|
|
@throws NoSuchAlgorithmException if the algorithm is not implemented by providers
|
|
*/
|
|
public static KeyFactory getInstance(String algorithm)
|
|
throws NoSuchAlgorithmException
|
|
{
|
|
Provider[] p = Security.getProviders();
|
|
|
|
for (int i = 0; i < p.length; i++)
|
|
{
|
|
String classname = p[i].getProperty("KeyFactory." + algorithm);
|
|
if (classname != null)
|
|
return getInstance(classname, algorithm, p[i]);
|
|
}
|
|
|
|
throw new NoSuchAlgorithmException(algorithm);
|
|
}
|
|
|
|
/**
|
|
Gets an instance of the KeyFactory class representing
|
|
the specified key factory from the specified provider.
|
|
If the algorithm is not found then, it throws
|
|
NoSuchAlgorithmException. If the provider is not found, then
|
|
it throws NoSuchProviderException.
|
|
|
|
@param algorithm the name of algorithm to choose
|
|
@param provider the name of the provider to find the algorithm in
|
|
@return a KeyFactory repesenting the desired algorithm
|
|
|
|
@throws NoSuchAlgorithmException if the algorithm is not implemented by the provider
|
|
@throws NoSuchProviderException if the provider is not found
|
|
*/
|
|
public static KeyFactory getInstance(String algorithm, String provider)
|
|
throws NoSuchAlgorithmException, NoSuchProviderException
|
|
{
|
|
Provider p = Security.getProvider(provider);
|
|
if (p == null)
|
|
throw new NoSuchProviderException();
|
|
|
|
return getInstance(p.getProperty("KeyFactory." + algorithm),
|
|
algorithm, p);
|
|
}
|
|
|
|
private static KeyFactory getInstance(String classname,
|
|
String algorithm,
|
|
Provider provider)
|
|
throws NoSuchAlgorithmException
|
|
{
|
|
|
|
try
|
|
{
|
|
return new KeyFactory((KeyFactorySpi) Class.forName(classname).
|
|
newInstance(), provider, algorithm);
|
|
}
|
|
catch (ClassNotFoundException cnfe)
|
|
{
|
|
throw new NoSuchAlgorithmException("Class not found");
|
|
}
|
|
catch (InstantiationException ie)
|
|
{
|
|
throw new NoSuchAlgorithmException("Class instantiation failed");
|
|
}
|
|
catch (IllegalAccessException iae)
|
|
{
|
|
throw new NoSuchAlgorithmException("Illegal Access");
|
|
}
|
|
}
|
|
|
|
/**
|
|
Gets the provider that the class is from.
|
|
|
|
@return the provider of this class
|
|
*/
|
|
public final Provider getProvider()
|
|
{
|
|
return provider;
|
|
}
|
|
|
|
/**
|
|
Returns the name of the algorithm used
|
|
|
|
@return A string with the name of the algorithm
|
|
*/
|
|
public final String getAlgorithm()
|
|
{
|
|
return algorithm;
|
|
}
|
|
|
|
/**
|
|
Generates a public key from the provided key specification.
|
|
|
|
@param keySpec key specification
|
|
|
|
@return the public key
|
|
|
|
@throws InvalidKeySpecException invalid key specification 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 from the provided key specification.
|
|
|
|
@param keySpec key specification
|
|
|
|
@return the private key
|
|
|
|
@throws InvalidKeySpecException invalid key specification for
|
|
this key factory to produce a private key
|
|
*/
|
|
public final PrivateKey generatePrivate(KeySpec keySpec) throws
|
|
InvalidKeySpecException
|
|
{
|
|
return keyFacSpi.engineGeneratePrivate(keySpec);
|
|
}
|
|
|
|
/**
|
|
Returns a key specification for the given key. keySpec
|
|
identifies the specification class to return the key
|
|
material in.
|
|
|
|
@param key the key
|
|
@param keySpec the specification class to return the
|
|
key material in.
|
|
|
|
@return the key specification in an instance of the requested
|
|
specification class
|
|
|
|
@throws InvalidKeySpecException the requested key specification
|
|
is inappropriate for this key or the key is
|
|
unrecognized.
|
|
*/
|
|
public final KeySpec getKeySpec(Key key, Class keySpec)
|
|
throws InvalidKeySpecException
|
|
{
|
|
return keyFacSpi.engineGetKeySpec(key, keySpec);
|
|
}
|
|
|
|
/**
|
|
Translates the key from an unknown or untrusted provider
|
|
into a key for this key factory.
|
|
|
|
@param the key from an unknown or untrusted provider
|
|
|
|
@return the translated key
|
|
|
|
@throws InvalidKeySpecException if the key cannot be
|
|
processed by this key factory
|
|
*/
|
|
public final Key translateKey(Key key) throws InvalidKeyException
|
|
{
|
|
return keyFacSpi.engineTranslateKey(key);
|
|
}
|
|
}
|