1/*
2 * Copyright (c) 2009, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.  Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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23 * questions.
24 */
25
26package com.sun.security.jgss;
27
28import org.ietf.jgss.*;
29
30/**
31 * The extended GSSContext interface for supporting additional
32 * functionalities not defined by {@code org.ietf.jgss.GSSContext},
33 * such as querying context-specific attributes.
34 */
35public interface ExtendedGSSContext extends GSSContext {
36
37    /**
38     * Return the mechanism-specific attribute associated with {@code type}.
39     * <p>
40     * If there is a security manager, an {@link InquireSecContextPermission}
41     * with the name {@code type.mech} must be granted. Otherwise, this could
42     * result in a {@link SecurityException}.
43     * <p>
44     * Example:
45     * <pre>
46     *      GSSContext ctxt = m.createContext(...)
47     *      // Establishing the context
48     *      if (ctxt instanceof ExtendedGSSContext) {
49     *          ExtendedGSSContext ex = (ExtendedGSSContext)ctxt;
50     *          try {
51     *              Key key = (key)ex.inquireSecContext(
52     *                      InquireType.KRB5_GET_SESSION_KEY);
53     *              // read key info
54     *          } catch (GSSException gsse) {
55     *              // deal with exception
56     *          }
57     *      }
58     * </pre>
59     * @param type the type of the attribute requested
60     * @return the attribute, see the method documentation for details.
61     * @throws GSSException containing  the following
62     * major error codes:
63     *   {@link GSSException#BAD_MECH GSSException.BAD_MECH} if the mechanism
64     *   does not support this method,
65     *   {@link GSSException#UNAVAILABLE GSSException.UNAVAILABLE} if the
66     *   type specified is not supported,
67     *   {@link GSSException#NO_CONTEXT GSSException.NO_CONTEXT} if the
68     *   security context is invalid,
69     *   {@link GSSException#FAILURE GSSException.FAILURE} for other
70     *   unspecified failures.
71     * @throws SecurityException if a security manager exists and a proper
72     *   {@link InquireSecContextPermission} is not granted.
73     * @see InquireSecContextPermission
74     * @see InquireType
75     */
76    public Object inquireSecContext(InquireType type)
77            throws GSSException;
78
79    /**
80     * Requests that the delegation policy be respected. When a true value is
81     * requested, the underlying context would use the delegation policy
82     * defined by the environment as a hint to determine whether credentials
83     * delegation should be performed. This request can only be made on the
84     * context initiator's side and it has to be done prior to the first
85     * call to <code>initSecContext</code>.
86     * <p>
87     * When this flag is false, delegation will only be tried when the
88     * {@link GSSContext#requestCredDeleg(boolean) credentials delegation flag}
89     * is true.
90     * <p>
91     * When this flag is true but the
92     * {@link GSSContext#requestCredDeleg(boolean) credentials delegation flag}
93     * is false, delegation will be only tried if the delegation policy permits
94     * delegation.
95     * <p>
96     * When both this flag and the
97     * {@link GSSContext#requestCredDeleg(boolean) credentials delegation flag}
98     * are true, delegation will be always tried. However, if the delegation
99     * policy does not permit delegation, the value of
100     * {@link #getDelegPolicyState} will be false, even
101     * if delegation is performed successfully.
102     * <p>
103     * In any case, if the delegation is not successful, the value returned
104     * by {@link GSSContext#getCredDelegState()} is false, and the value
105     * returned by {@link #getDelegPolicyState()} is also false.
106     * <p>
107     * Not all mechanisms support delegation policy. Therefore, the
108     * application should check to see if the request was honored with the
109     * {@link #getDelegPolicyState() getDelegPolicyState} method. When
110     * delegation policy is not supported, <code>requestDelegPolicy</code>
111     * should return silently without throwing an exception.
112     * <p>
113     * Note: for the Kerberos 5 mechanism, the delegation policy is expressed
114     * through the OK-AS-DELEGATE flag in the service ticket. When it's true,
115     * the KDC permits delegation to the target server. In a cross-realm
116     * environment, in order for delegation be permitted, all cross-realm TGTs
117     * on the authentication path must also have the OK-AS-DELAGATE flags set.
118     * @param state true if the policy should be respected
119     * @throws GSSException containing the following
120     * major error codes:
121     *   {@link GSSException#FAILURE GSSException.FAILURE}
122     */
123    public void requestDelegPolicy(boolean state) throws GSSException;
124
125    /**
126     * Returns the delegation policy response. Called after a security context
127     * is established. This method can be only called on the initiator's side.
128     * See {@link ExtendedGSSContext#requestDelegPolicy}.
129     * @return the delegation policy response
130     */
131    public boolean getDelegPolicyState();
132}
133