kerberosticket.java

Mobile 应用程序使用 Java Micro Edition (Java ME) 平台

/*
 * @(#)KerberosTicket.java	1.21 06/07/27
 *
 * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
  
package javax.security.auth.kerberos;

import java.io.*;
import java.util.Date;
import java.util.Arrays;
import java.net.InetAddress;
import javax.crypto.SecretKey;
import javax.security.auth.Refreshable;
import javax.security.auth.Destroyable;
import javax.security.auth.RefreshFailedException;
import javax.security.auth.DestroyFailedException;
import sun.misc.HexDumpEncoder;
import sun.security.krb5.EncryptionKey;
import sun.security.krb5.Asn1Exception;
import sun.security.util.*;

/**
 * This class encapsulates a Kerberos ticket and associated
 * information as viewed from the client's point of view. It captures all
 * information that the Key Distribution Center (KDC) sends to the client
 * in the reply message KDC-REP defined in the Kerberos Protocol
 * Specification (<a href=http://www.ietf.org/rfc/rfc1510.txt>RFC 1510</a>).
 * <p>
 * All Kerberos JAAS login modules that authenticate a user to a KDC should
 * use this class. Where available, the login module might even read this 
 * information from a ticket cache in the operating system instead of
 * directly communicating with the KDC. During the commit phase of the JAAS
 * authentication process, the JAAS login module should instantiate this
 * class and store the instance in the private credential set of a
 * {@link javax.security.auth.Subject Subject}.<p>
 *
 * It might be necessary for the application to be granted a
 * {@link javax.security.auth.PrivateCredentialPermission 
 * PrivateCredentialPermission} if it needs to access a KerberosTicket
 * instance from a Subject. This permission is not needed when the
 * application depends on the default JGSS Kerberos mechanism to access the
 * KerberosTicket. In that case, however, the application will need an
 * appropriate
 * {@link javax.security.auth.kerberos.ServicePermission ServicePermission}.
 * <p>
 * Note that this class is applicable to both ticket granting tickets and
 * other regular service tickets. A ticket granting ticket is just a
 * special case of a more generalized service ticket.
 *
 * @see javax.security.auth.Subject
 * @see javax.security.auth.PrivateCredentialPermission
 * @see javax.security.auth.login.LoginContext
 * @see org.ietf.jgss.GSSCredential
 * @see org.ietf.jgss.GSSManager
 * 
 * @author Mayank Upadhyay
 * @version 1.21, 07/27/06
 * @since 1.4
 */
public class KerberosTicket implements Destroyable, Refreshable,
	 java.io.Serializable {

    private static final long serialVersionUID = 7395334370157380539L;

    // XXX Make these flag indices public
    private static final int FORWARDABLE_TICKET_FLAG = 1;
    private static final int FORWARDED_TICKET_FLAG   = 2;
    private static final int PROXIABLE_TICKET_FLAG   = 3;
    private static final int PROXY_TICKET_FLAG       = 4;
    private static final int POSTDATED_TICKET_FLAG   = 6;
    private static final int RENEWABLE_TICKET_FLAG   = 8;
    private static final int INITIAL_TICKET_FLAG     = 9;

    private static final int NUM_FLAGS = 32;

    /**
     * 
     * ASN.1 DER Encoding of the Ticket as defined in the 
     * Kerberos Protocol Specification RFC1510.
     *
     * @serial
     */

    private byte[] asn1Encoding;

    /**
     *<code>KeyImpl</code> is serialized by writing out the ASN1 Encoded bytes 
     * of the encryption key. The ASN1 encoding is defined in RFC1510 and as
     * follows:
     * <pre>		
     *			EncryptionKey ::=   SEQUENCE {
     *				keytype[0]    INTEGER,
     *				keyvalue[1]   OCTET STRING    	
     *				}
     * </pre>
     *
     * @serial
     */

    private KeyImpl sessionKey;

    /**
     * 
     * Ticket Flags as defined in the Kerberos Protocol Specification RFC1510.
     *
     * @serial
     */

    private boolean[] flags;

    /**
     * 
     * Time of initial authentication 
     *
     * @serial
     */

    private Date authTime;

    /**
     * 
     * Time after which the ticket is valid.
     * @serial
     */
    private Date startTime;

    /**
     * 
     * Time after which the ticket will not be honored. (its expiration time).
     *
     * @serial
     */

    private Date endTime;

    /**
     * 
     * For renewable Tickets it indicates the maximum endtime that may be 
     * included in a renewal. It can be thought of as the absolute expiration 
     * time for the ticket, including all renewals. This field may be null
     * for tickets that are not renewable.
     *
     * @serial
     */

    private Date renewTill;

    /**
     * 
     * Client that owns the service ticket
     * 
     * @serial
     */

    private KerberosPrincipal client;

    /**
     * 
     * The service for which the ticket was issued.
     * 
     * @serial
     */

    private KerberosPrincipal server;
	
    /**
     * 
     * The addresses from where the ticket may be used by the client. 
     * This field may be null when the ticket is usable from any address.
     *
     * @serial
     */


    private InetAddress[] clientAddresses;

    private transient boolean destroyed = false;

    /**
     * Constructs a KerberosTicket using credentials information that a
     * client either receives from a KDC or reads from a cache.
     *
     * @param asn1Encoding the ASN.1 encoding of the ticket as defined by
     * the Kerberos protocol specification.
     * @param client the client that owns this service
     * ticket
     * @param server the service that this ticket is for
     * @param sessionKey the raw bytes for the session key that must be
     * used to encrypt the authenticator that will be sent to the server
     * @param keyType the key type for the session key as defined by the
     * Kerberos protocol specification.
     * @param flags the ticket flags. Each element in this array indicates
     * the value for the corresponding bit in the ASN.1 BitString that
     * represents the ticket flags. If the number of elements in this array 
     * is less than the number of flags used by the Kerberos protocol,
     * then the missing flags will be filled in with false.
     * @param authTime the time of initial authentication for the client
     * @param startTime the time after which the ticket will be valid. This 
     * may be null in which case the value of authTime is treated as the
     * startTime.
     * @param endTime the time after which the ticket will no longer be
     * valid
     * @param renewTill an absolute expiration time for the ticket,
     * including all renewal that might be possible. This field may be null 
     * for tickets that are not renewable.
     * @param clientAddresses the addresses from where the ticket may be
     * used by the client. This field may be null when the ticket is usable 
     * from any address.
     */
    public KerberosTicket(byte[] asn1Encoding, 
			 KerberosPrincipal client,
			 KerberosPrincipal server,
			 byte[] sessionKey,
			 int keyType,
			 boolean[] flags,
			 Date authTime,
			 Date startTime,
			 Date endTime,
			 Date renewTill,
			 InetAddress[] clientAddresses) {
       
	init(asn1Encoding, client, server, sessionKey, keyType, flags,
	    authTime, startTime, endTime, renewTill, clientAddresses);
    }
    
    private void init(byte[] asn1Encoding, 
			 KerberosPrincipal client,
			 KerberosPrincipal server,
			 byte[] sessionKey,
			 int keyType,
			 boolean[] flags,
			 Date authTime,
			 Date startTime,
			 Date endTime,
			 Date renewTill,
			 InetAddress[] clientAddresses) {

	if (asn1Encoding == null)
	   throw new IllegalArgumentException("ASN.1 encoding of ticket"
					      + " cannot be null");
	this.asn1Encoding = asn1Encoding.clone();

	if (client == null)
	   throw new IllegalArgumentException("Client name in ticket"
					      + " cannot be null");
	this.client = client;

	if (server == null)
	   throw new IllegalArgumentException("Server name in ticket"
					      + " cannot be null");
	this.server = server;

	if (sessionKey == null)
	   throw new IllegalArgumentException("Session key for ticket"
					      + " cannot be null");
	this.sessionKey = new KeyImpl(sessionKey, keyType);

	if (flags != null) {
	   if (flags.length >= NUM_FLAGS)
		this.flags = (boolean[]) flags.clone();
	   else {
		this.flags = new boolean[NUM_FLAGS];
		// Fill in whatever we have
		for (int i = 0; i < flags.length; i++)
		    this.flags[i] = flags[i];
	   }
	} else
	   this.flags = new boolean[NUM_FLAGS];

	if (this.flags[RENEWABLE_TICKET_FLAG]) {
	   if (renewTill == null)
		throw new IllegalArgumentException("The renewable period "
		       + "end time cannot be null for renewable tickets.");

	   this.renewTill = renewTill;
	}

	this.authTime = authTime;

	this.startTime = (startTime != null? startTime: authTime);

	if (endTime == null)
	   throw new IllegalArgumentException("End time for ticket validity"
					      + " cannot be null");
	this.endTime = endTime;

	if (clientAddresses != null)
	   this.clientAddresses = (InetAddress[]) clientAddresses.clone();
    }

    /**
     * Returns the client principal associated with this ticket.
     *
     * @return the client principal.
     */
    public final KerberosPrincipal getClient() {
	return client;
    }
    
    /**
     * Returns the service principal associated with this ticket.
     *
     * @return the service principal.
     */
    public final KerberosPrincipal getServer() {
	return server;
    }
    
    /**
     * Returns the session key associated with this ticket.
     *
     * @return the session key.
     */
    public final SecretKey getSessionKey() {
	if (destroyed)
	    throw new IllegalStateException("This ticket is no longer valid");
	return sessionKey;
    }

    /**
     * Returns the key type of the session key associated with this
     * ticket as defined by the Kerberos Protocol Specification.
     *
     * @return the key type of the session key associated with this
     * ticket.
     *
     * @see #getSessionKey()
     */
    public final int getSessionKeyType() {
	if (destroyed)
	    throw new IllegalStateException("This ticket is no longer valid");
	return sessionKey.getKeyType();
    }

    /** 
     * Determines if this ticket is forwardable.
     *
     * @return true if this ticket is forwardable, false if not.
     */
    public final boolean isForwardable() {
	return flags[FORWARDABLE_TICKET_FLAG];
    }

    /** 
     * Determines if this ticket had been forwarded or was issued based on
     * authentication involving a forwarded ticket-granting ticket.
     *
     * @return true if this ticket had been forwarded or was issued based on
     * authentication involving a forwarded ticket-granting ticket,
     * false otherwise.
     */
    public final boolean isForwarded() {
	return flags[FORWARDED_TICKET_FLAG];
    }

    /** 
     * Determines if this ticket is proxiable.
     *
     * @return true if this ticket is proxiable, false if not.
     */
    public final boolean isProxiable() {
	return flags[PROXIABLE_TICKET_FLAG];
    }