/*

 * Copyright 2009 Sun Microsystems, Inc.  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.  Sun designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

package com.sun.security.jgss;

import org.ietf.jgss.*;

/**

 * The extended GSSContext interface for supporting additional

 * functionalities not defined by {@code org.ietf.jgss.GSSContext},

 * such as querying context-specific attributes.

 */

public interface ExtendedGSSContext extends GSSContext {

    /**

     * Return the mechanism-specific attribute associated with {@code type}.

     * <br><br>

     * For each supported attribute type, the type for the output are

     * defined below.

     * <ol>

     * <li>{@code KRB5_GET_SESSION_KEY}:

     * the returned object is an instance of {@link java.security.Key},

     * which has the following properties:

     *    <ul>

     *    <li>Algorithm: enctype as a string, where

     *        enctype is defined in RFC 3961, section 8.

     *    <li>Format: "RAW"

     *    <li>Encoded form: the raw key bytes, not in any ASN.1 encoding

     *    </ul>

     * </ol>

     *

     * If there is a security manager, an {@link InquireSecContextPermission}

     * with the name {@code type.mech} must be granted. Otherwise, this could

     * result in a {@link SecurityException}.<p>

     *

     * Example:

     * <pre>

     *      GSSContext ctxt = m.createContext(...)

     *      // Establishing the context

     *      if (ctxt instanceof ExtendedGSSContext) {

     *          ExtendedGSSContext ex = (ExtendedGSSContext)ctxt;

     *          try {

     *              Key key = (key)ex.inquireSecContext(

     *                      InquireType.KRB5_GET_SESSION_KEY);

     *              // read key info

     *          } catch (GSSException gsse) {

     *              // deal with exception

     *          }

     *      }

     * </pre>

     * @param type the type of the attribute requested

     * @return the attribute, see the method documentation for details.

     * @throws GSSException containing  the following

     * major error codes:

     *   {@link GSSException#BAD_MECH GSSException.BAD_MECH} if the mechanism

     *   does not support this method,

     *   {@link GSSException#UNAVAILABLE GSSException.UNAVAILABLE} if the

     *   type specified is not supported,

     *   {@link GSSException#NO_CONTEXT GSSException.NO_CONTEXT} if the

     *   security context is invalid,

     *   {@link GSSException#FAILURE GSSException.FAILURE} for other

     *   unspecified failures.

     * @throws SecurityException if a security manager exists and a proper

     *   {@link InquireSecContextPermission} is not granted.

     * @see InquireSecContextPermission

     */

    public Object inquireSecContext(InquireType type)

            throws GSSException;

}