AliasKeyManager.java

/*
 * Copyright 1999-2004 The Apache Software Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.smscserver.ssl.impl;

import java.net.Socket;
import java.security.Principal;
import java.security.PrivateKey;
import java.security.cert.X509Certificate;

import javax.net.ssl.KeyManager;
import javax.net.ssl.X509KeyManager;

/**
 * <strong>Internal class, do not use directly.</strong>
 * 
 * X509KeyManager which allows selection of a specific keypair and certificate chain (identified by their keystore alias
 * name) to be used by the server to authenticate itself to SSL clients.
 * 
 * This class is only used on Java 1.4 systems, on Java 1.5 and newer the @see {@link ExtendedAliasKeyManager} is used
 * instead
 * 
 * Based of org.apache.tomcat.util.net.jsse.JSSEKeyManager.
 * 
 * @author hceylan
 */
public final class AliasKeyManager implements X509KeyManager {

    private final X509KeyManager delegate;

    private final String serverKeyAlias;

    /**
     * Constructor.
     * 
     * @param mgr
     *            The X509KeyManager used as a delegate
     * @param keyAlias
     *            The alias name of the server's keypair and supporting certificate chain
     */
    public AliasKeyManager(KeyManager mgr, String keyAlias) {
        this.delegate = (X509KeyManager) mgr;
        this.serverKeyAlias = keyAlias;
    }

    /**
     * Choose an alias to authenticate the client side of a secure socket, given the public key type and the list of
     * certificate issuer authorities recognized by the peer (if any).
     * 
     * @param keyType
     *            The key algorithm type name(s), ordered with the most-preferred key type first
     * @param issuers
     *            The list of acceptable CA issuer subject names, or null if it does not matter which issuers are used
     * @param socket
     *            The socket to be used for this connection. This parameter can be null, in which case this method will
     *            return the most generic alias to use
     * 
     * @return The alias name for the desired key, or null if there are no matches
     */
    public String chooseClientAlias(String[] keyType, Principal[] issuers, Socket socket) {
        return this.delegate.chooseClientAlias(keyType, issuers, socket);
    }

    /**
     * Returns this key manager's server key alias that was provided in the constructor.
     * 
     * @param keyType
     *            The key algorithm type name
     * @param issuers
     *            The list of acceptable CA issuer subject names, or null if it does not matter which issuers are used
     *            (ignored)
     * @param socket
     *            The socket to be used for this connection. This parameter can be null, in which case this method will
     *            return the most generic alias to use (ignored)
     * 
     * @return Alias name for the desired key
     */
    public String chooseServerAlias(String keyType, Principal[] issuers, Socket socket) {
        if (this.serverKeyAlias != null) {
            PrivateKey key = this.delegate.getPrivateKey(this.serverKeyAlias);
            if (key != null) {
                if (key.getAlgorithm().equals(keyType)) {
                    return this.serverKeyAlias;
                } else {
                    return null;
                }
            } else {
                return null;
            }
        } else {
            return this.delegate.chooseServerAlias(keyType, issuers, socket);
        }
    }

    /**
     * Returns the certificate chain associated with the given alias.
     * 
     * @param alias
     *            The alias name
     * 
     * @return Certificate chain (ordered with the user's certificate first and the root certificate authority last), or
     *         null if the alias can't be found
     */
    public X509Certificate[] getCertificateChain(String alias) {
        return this.delegate.getCertificateChain(alias);
    }

    /**
     * Get the matching aliases for authenticating the client side of a secure socket, given the public key type and the
     * list of certificate issuer authorities recognized by the peer (if any).
     * 
     * @param keyType
     *            The key algorithm type name
     * @param issuers
     *            The list of acceptable CA issuer subject names, or null if it does not matter which issuers are used
     * 
     * @return Array of the matching alias names, or null if there were no matches
     */
    public String[] getClientAliases(String keyType, Principal[] issuers) {
        return this.delegate.getClientAliases(keyType, issuers);
    }

    /**
     * Returns the key associated with the given alias.
     * 
     * @param alias
     *            The alias name
     * 
     * @return The requested key, or null if the alias can't be found
     */
    public PrivateKey getPrivateKey(String alias) {
        return this.delegate.getPrivateKey(alias);
    }

    /**
     * Get the matching aliases for authenticating the server side of a secure socket, given the public key type and the
     * list of certificate issuer authorities recognized by the peer (if any).
     * 
     * @param keyType
     *            The key algorithm type name
     * @param issuers
     *            The list of acceptable CA issuer subject names, or null if it does not matter which issuers are used
     * 
     * @return Array of the matching alias names, or null if there were no matches
     */
    public String[] getServerAliases(String keyType, Principal[] issuers) {
        return this.delegate.getServerAliases(keyType, issuers);
    }
}