package gnu.crypto.key;
// ----------------------------------------------------------------------------
// $Id: KeyAgreementFactory.java,v 1.3 2005/10/06 04:24:16 rsdio Exp $
//
// Copyright (C) 2003 Free Software Foundation, Inc.
//
// This file is part of GNU Crypto.
//
// GNU Crypto 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 Crypto 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 this program; 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.
// ----------------------------------------------------------------------------
import gnu.crypto.Registry;
import gnu.crypto.key.dh.DiffieHellmanSender;
import gnu.crypto.key.dh.DiffieHellmanReceiver;
import gnu.crypto.key.dh.ElGamalSender;
import gnu.crypto.key.dh.ElGamalReceiver;
import gnu.crypto.key.srp6.SRP6Host;
import gnu.crypto.key.srp6.SRP6User;
import gnu.crypto.key.srp6.SRP6SaslClient;
import gnu.crypto.key.srp6.SRP6SaslServer;
import gnu.crypto.key.srp6.SRP6TLSClient;
import gnu.crypto.key.srp6.SRP6TLSServer;
import java.util.Collections;
import java.util.HashSet;
import java.util.Set;
/**
* <p>A <i>Factory</i> class to generate key agreement protocol handlers.</p>
*
* @version $Revision: 1.3 $
*/
public class KeyAgreementFactory {
// Constants and variables
// -------------------------------------------------------------------------
// Constructor(s)
// -------------------------------------------------------------------------
/** Trivial constructor to enforce <i>Singleton</i> pattern. */
private KeyAgreementFactory() {
super();
}
// Class methods
// -------------------------------------------------------------------------
/**
* <p>Returns an instance of a key agreeent protocol handler, for party
* <code>A</code> in a two-party <code>A..B</code> exchange, given the
* canonical name of this protocol. Party <code>A</code> is usually the
* initiator of the exchange.</p>
*
* @param name the case-insensitive key agreement protocol name.
* @return an instance of the key agreement protocol handler for party
* <code>A</code>, or <code>null</code> if none found.
*/
public static IKeyAgreementParty getPartyAInstance(String name) {
if (name == null) {
return null;
}
name = name.trim();
IKeyAgreementParty result = null;
if (name.equalsIgnoreCase(Registry.DH_KA)) {
result = new DiffieHellmanSender();
} else if (name.equalsIgnoreCase(Registry.ELGAMAL_KA)) {
result = new ElGamalSender();
} else if (name.equalsIgnoreCase(Registry.SRP6_KA)) {
result = new SRP6User();
} else if (name.equalsIgnoreCase(Registry.SRP_SASL_KA)) {
result = new SRP6SaslClient();
} else if (name.equalsIgnoreCase(Registry.SRP_TLS_KA)) {
result = new SRP6TLSClient();
}
return result;
}
/**
* <p>Returns an instance of a key agreeent protocol handler, for party
* <code>B</code> in a two-party <code>A..B</code> exchange, given the
* canonical name of this protocol.</p>
*
* @param name the case-insensitive key agreement protocol name.
* @return an instance of the key agreement protocol handler for party
* <code>B</code>, or <code>null</code> if none found.
*/
public static IKeyAgreementParty getPartyBInstance(String name) {
if (name == null) {
return null;
}
name = name.trim();
IKeyAgreementParty result = null;
if (name.equalsIgnoreCase(Registry.DH_KA)) {
result = new DiffieHellmanReceiver();
} else if (name.equalsIgnoreCase(Registry.ELGAMAL_KA)) {
result = new ElGamalReceiver();
} else if (name.equalsIgnoreCase(Registry.SRP6_KA)) {
result = new SRP6Host();
} else if (name.equalsIgnoreCase(Registry.SRP_SASL_KA)) {
result = new SRP6SaslServer();
} else if (name.equalsIgnoreCase(Registry.SRP_TLS_KA)) {
result = new SRP6TLSServer();
}
return result;
}
/**
* <p>Returns a {@link Set} of key agreement protocol names supported by this
* <i>Factory</i>.</p>
*
* @return a {@link Set} of key agreement protocol names (Strings).
*/
public static final Set getNames() {
HashSet hs = new HashSet();
hs.add(Registry.DH_KA);
hs.add(Registry.ELGAMAL_KA);
hs.add(Registry.SRP6_KA);
hs.add(Registry.SRP_SASL_KA);
hs.add(Registry.SRP_TLS_KA);
return Collections.unmodifiableSet(hs);
}
}