Java example source code file (GSSCredential.java)

This example Java source code file (GSSCredential.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

accept_only, cloneable, default_lifetime, gsscredential, gssexception, gssname, indefinite_lifetime, initiate_and_accept, initiate_only, oid

The GSSCredential.java Java example source code

/*
 * Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package org.ietf.jgss;

/**
 * This interface encapsulates the GSS-API credentials for an entity.  A
 * credential contains all the necessary cryptographic information to
 * enable the creation of a context on behalf of the entity that it
 * represents.  It may contain multiple, distinct, mechanism specific
 * credential elements, each containing information for a specific
 * security mechanism, but all referring to the same entity. A credential
 * may be used to perform context initiation, acceptance, or both.<p>
 *
 * Credentials are instantiated using one of the
 * <code>createCredential methods in the {@link GSSManager
 * GSSManager} class. GSS-API credential creation is not
 * intended to provide a "login to the network" function, as such a
 * function would involve the creation of new credentials rather than
 * merely acquiring a handle to existing credentials. The
 * <a href=package-summary.html#useSubjectCredsOnly>section on credential
 * acquisition</a> in the package level description describes
 * how existing credentials are acquired in the Java platform. GSS-API
 * implementations must impose a local access-control policy on callers to
 * prevent unauthorized callers from acquiring credentials to which they
 * are not entitled. <p>
 *
 * Applications will create a credential object passing the desired
 * parameters.  The application can then use the query methods to obtain
 * specific information about the instantiated credential object.
 * When the credential is no longer needed, the application should call
 * the {@link #dispose() dispose} method to release any resources held by
 * the credential object and to destroy any cryptographically sensitive
 * information.<p>
 *
 * This example code demonstrates the creation of a GSSCredential
 * implementation for a specific entity, querying of its fields, and its
 * release when it is no longer needed:<p>
 * <pre>
 *    GSSManager manager = GSSManager.getInstance();
 *
 *    // start by creating a name object for the entity
 *    GSSName name = manager.createName("myusername", GSSName.NT_USER_NAME);
 *
 *    // now acquire credentials for the entity
 *    GSSCredential cred = manager.createCredential(name,
 *                    GSSCredential.ACCEPT_ONLY);
 *
 *    // display credential information - name, remaining lifetime,
 *    // and the mechanisms it has been acquired over
 *    System.out.println(cred.getName().toString());
 *    System.out.println(cred.getRemainingLifetime());
 *
 *    Oid [] mechs = cred.getMechs();
 *    if (mechs != null) {
 *            for (int i = 0; i < mechs.length; i++)
 *                    System.out.println(mechs[i].toString());
 *    }
 *
 *    // release system resources held by the credential
 *    cred.dispose();
 * </pre>
 *
 * @see GSSManager#createCredential(int)
 * @see GSSManager#createCredential(GSSName, int, Oid, int)
 * @see GSSManager#createCredential(GSSName, int, Oid[], int)
 * @see #dispose()
 *
 * @author Mayank Upadhyay
 * @since 1.4
 */
public interface GSSCredential extends Cloneable{

    /**
     * Credential usage flag requesting that it be usable
     * for both context initiation and acceptance.
     *
     */
    public static final int INITIATE_AND_ACCEPT = 0;


    /**
     * Credential usage flag requesting that it be usable
     * for context initiation only.
     *
     */
    public static final int INITIATE_ONLY = 1;


    /**
     * Credential usage flag requesting that it be usable
     * for context acceptance only.
     *
     */
    public static final int ACCEPT_ONLY = 2;


    /**
     * A lifetime constant representing the default credential lifetime. This
     * value it set to 0.
     */
    public static final int DEFAULT_LIFETIME = 0;

    /**
     * A lifetime constant representing indefinite credential lifetime.
     * This value must is set to the maximum integer value in Java -
     * {@link java.lang.Integer#MAX_VALUE Integer.MAX_VALUE}.
     */
    public static final int INDEFINITE_LIFETIME = Integer.MAX_VALUE;

    /**
     * Releases any sensitive information that the GSSCredential object may
     * be containing.  Applications should call this method as soon as the
     * credential is no longer needed to minimize the time any sensitive
     * information is maintained.
     *
     * @throws GSSException containing the following
     * major error codes:
     *         {@link GSSException#FAILURE GSSException.FAILURE}
     */
    public void dispose() throws GSSException;

    /**
     *  Retrieves the name of the entity that the credential asserts.
     *
     * @return a GSSName representing the entity
     *
     * @throws GSSException containing the following
     * major error codes:
     *         {@link GSSException#FAILURE GSSException.FAILURE}
     */
    public GSSName getName() throws GSSException;

    /**
     * Retrieves a Mechanism Name of the entity that the credential
     * asserts. This is equivalent to calling {@link
     * GSSName#canonicalize(Oid) canonicalize} on the value returned by
     * the other form of {@link #getName() getName}.
     *
     * @param mech the Oid of the mechanism for which the Mechanism Name
     * should be returned.
     * @return a GSSName representing the entity canonicalized for the
     * desired mechanism
     *
     * @throws GSSException containing the following
     * major error codes:
     *         {@link GSSException#BAD_MECH GSSException.BAD_MECH},
     *         {@link GSSException#FAILURE GSSException.FAILURE}
     */
    public GSSName getName(Oid mech) throws GSSException;

    /**
     * Returns the remaining lifetime in seconds for a credential.  The
     * remaining lifetime is the minimum lifetime amongst all of the underlying
     * mechanism specific credential elements.
     *
     * @return the minimum remaining lifetime in seconds for this
     * credential. A return value of {@link #INDEFINITE_LIFETIME
     * INDEFINITE_LIFETIME} indicates that the credential does
     * not expire. A return value of 0 indicates that the credential is
     * already expired.
     *
     * @see #getRemainingInitLifetime(Oid)
     * @see #getRemainingAcceptLifetime(Oid)
     *
     * @throws GSSException containing the following
     * major error codes:
     *         {@link GSSException#FAILURE GSSException.FAILURE}
     */
    public int getRemainingLifetime() throws GSSException;

    /**
     * Returns the lifetime in seconds for the credential to remain capable
     * of initiating security contexts using the specified mechanism. This
     * method queries the initiator credential element that belongs to the
     * specified mechanism.
     *
     * @return the number of seconds remaining in the life of this credential
     * element. A return value of {@link #INDEFINITE_LIFETIME
     * INDEFINITE_LIFETIME} indicates that the credential element does not
     * expire.  A return value of 0 indicates that the credential element is
     * already expired.
     *
     * @param mech the Oid of the mechanism whose initiator credential element
     * should be queried.
     *
     * @throws GSSException containing the following
     * major error codes:
     *         {@link GSSException#BAD_MECH GSSException.BAD_MECH},
     *         {@link GSSException#FAILURE GSSException.FAILURE}
     */
    public int getRemainingInitLifetime(Oid mech) throws GSSException;

    /**
     * Returns the lifetime in seconds for the credential to remain capable
     * of accepting security contexts using the specified mechanism. This
     * method queries the acceptor credential element that belongs to the
     * specified mechanism.
     *
     * @return the number of seconds remaining in the life of this credential
     * element. A return value of {@link #INDEFINITE_LIFETIME
     * INDEFINITE_LIFETIME} indicates that the credential element does not
     * expire.  A return value of 0 indicates that the credential element is
     * already expired.
     *
     * @param mech the Oid of the mechanism whose acceptor credential element
     * should be queried.
     *
     * @throws GSSException containing the following
     * major error codes:
     *         {@link GSSException#BAD_MECH GSSException.BAD_MECH},
     *         {@link GSSException#FAILURE GSSException.FAILURE}
     */
    public int getRemainingAcceptLifetime(Oid mech) throws GSSException;

    /**
     * Returns the credential usage mode. In other words, it
     * tells us if this credential can be used for initiating or accepting
     * security contexts. It does not tell us which mechanism(s) has to be
     * used in order to do so. It is expected that an application will allow
     * the GSS-API to pick a default mechanism after calling this method.
     *
     * @return The return value will be one of {@link #INITIATE_ONLY
     * INITIATE_ONLY}, {@link #ACCEPT_ONLY ACCEPT_ONLY}, and {@link
     * #INITIATE_AND_ACCEPT INITIATE_AND_ACCEPT}.
     *
     * @throws GSSException containing the following
     * major error codes:
     *         {@link GSSException#FAILURE GSSException.FAILURE}
     */
    public int getUsage() throws GSSException;

    /**
     * Returns the credential usage mode for a specific mechanism. In other
     * words, it tells us if this credential can be used
     * for initiating or accepting security contexts with a given underlying
     * mechanism.
     *
     * @return The return value will be one of {@link #INITIATE_ONLY
     * INITIATE_ONLY}, {@link #ACCEPT_ONLY ACCEPT_ONLY}, and {@link
     * #INITIATE_AND_ACCEPT INITIATE_AND_ACCEPT}.
     * @param mech the Oid of the mechanism whose credentials usage mode is
     * to be determined.
     *
     * @throws GSSException containing the following
     * major error codes:
     *         {@link GSSException#BAD_MECH GSSException.BAD_MECH},
     *         {@link GSSException#FAILURE GSSException.FAILURE}
     */
    public int getUsage(Oid mech) throws GSSException;

    /**
     * Returns a list of mechanisms supported by this credential. It does
     * not tell us which ones can be used to initiate
     * contexts and which ones can be used to accept contexts. The
     * application must call the {@link #getUsage(Oid) getUsage} method with
     * each of the returned Oid's to determine the possible modes of
     * usage.
     *
     * @return an array of Oid's corresponding to the supported mechanisms.
     *
     * @throws GSSException containing the following
     * major error codes:
     *         {@link GSSException#FAILURE GSSException.FAILURE}
     */
    public Oid[] getMechs() throws GSSException;

    /**
     * Adds a mechanism specific credential-element to an existing
     * credential.  This method allows the construction of credentials, one
     * mechanism at a time.<p>
     *
     * This routine is envisioned to be used mainly by context acceptors
     * during the creation of acceptor credentials which are to be used
     * with a variety of clients using different security mechanisms.<p>
     *
     * This routine adds the new credential element "in-place".  To add the
     * element in a new credential, first call <code>clone to obtain a
     * copy of this credential, then call its <code>add method.

     *
     * As always, GSS-API implementations must impose a local access-control
     * policy on callers to prevent unauthorized callers from acquiring
     * credentials to which they are not entitled.
     *
     * Non-default values for initLifetime and acceptLifetime cannot always
     * be honored by the underlying mechanisms, thus callers should be
     * prepared to call {@link #getRemainingInitLifetime(Oid)
     * getRemainingInitLifetime} and {@link #getRemainingAcceptLifetime(Oid)
     * getRemainingAcceptLifetime} on the credential.
     *
     * @param name the name of the principal for whom this credential is to
     * be acquired.  Use <code>null to specify the default
     * principal.
     * @param initLifetime the number of seconds that the credential element
     * should remain valid for initiating of security contexts. Use {@link
     * GSSCredential#INDEFINITE_LIFETIME GSSCredential.INDEFINITE_LIFETIME}
     * to request that the credentials have the maximum permitted lifetime
     * for this.  Use {@link GSSCredential#DEFAULT_LIFETIME
     * GSSCredential.DEFAULT_LIFETIME} to request default credential lifetime
     * for this.
     * @param acceptLifetime the number of seconds that the credential
     * element should remain valid for accepting security contexts. Use {@link
     * GSSCredential#INDEFINITE_LIFETIME GSSCredential.INDEFINITE_LIFETIME}
     * to request that the credentials have the maximum permitted lifetime
     * for this.  Use {@link GSSCredential#DEFAULT_LIFETIME
     * GSSCredential.DEFAULT_LIFETIME} to request default credential lifetime
     * for this.
     * @param mech the mechanism over which the credential is to be acquired.
     * @param usage the usage mode that this credential
     * element should add to the credential. The value
     * of this parameter must be one of:
     * {@link #INITIATE_AND_ACCEPT INITIATE_AND_ACCEPT},
     * {@link #ACCEPT_ONLY ACCEPT_ONLY}, and
     * {@link #INITIATE_ONLY INITIATE_ONLY}.
     *
     * @throws GSSException containing the following
     * major error codes:
     *         {@link GSSException#DUPLICATE_ELEMENT
     *                          GSSException.DUPLICATE_ELEMENT},
     *         {@link GSSException#BAD_MECH GSSException.BAD_MECH},
     *         {@link GSSException#BAD_NAMETYPE GSSException.BAD_NAMETYPE},
     *         {@link GSSException#NO_CRED GSSException.NO_CRED},
     *         {@link GSSException#CREDENTIALS_EXPIRED
     *                                  GSSException.CREDENTIALS_EXPIRED},
     *         {@link GSSException#FAILURE GSSException.FAILURE}
     */
    public void add(GSSName name, int initLifetime, int acceptLifetime,
                    Oid mech, int usage) throws GSSException;

    /**
     * Tests if this GSSCredential asserts the same entity as the supplied
     * object.  The two credentials must be acquired over the same
     * mechanisms and must refer to the same principal.
     *
     * @return <code>true if the two GSSCredentials assert the same
     * entity; <code>false otherwise.
     * @param another another GSSCredential for comparison to this one
     */
    public boolean equals(Object another);

    /**
     * Returns a hashcode value for this GSSCredential.
     *
     * @return a hashCode value
     */
    public int hashCode();

}