View Javadoc

1   /*
2    * ====================================================================
3    * Licensed to the Apache Software Foundation (ASF) under one
4    * or more contributor license agreements.  See the NOTICE file
5    * distributed with this work for additional information
6    * regarding copyright ownership.  The ASF licenses this file
7    * to you under the Apache License, Version 2.0 (the
8    * "License"); you may not use this file except in compliance
9    * with the License.  You may obtain a copy of the License at
10   *
11   *   http://www.apache.org/licenses/LICENSE-2.0
12   *
13   * Unless required by applicable law or agreed to in writing,
14   * software distributed under the License is distributed on an
15   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
16   * KIND, either express or implied.  See the License for the
17   * specific language governing permissions and limitations
18   * under the License.
19   * ====================================================================
20   *
21   * This software consists of voluntary contributions made by many
22   * individuals on behalf of the Apache Software Foundation.  For more
23   * information on the Apache Software Foundation, please see
24   * <http://www.apache.org/>.
25   *
26   */
27  package org.apache.http.impl.auth;
28  
29  import org.apache.http.Header;
30  import org.apache.http.HttpRequest;
31  import org.apache.http.auth.AuthenticationException;
32  import org.apache.http.auth.Credentials;
33  import org.apache.http.protocol.HttpContext;
34  import org.apache.http.util.Args;
35  import org.ietf.jgss.GSSException;
36  import org.ietf.jgss.Oid;
37  
38  /**
39   * KERBEROS authentication scheme.
40   *
41   * @since 4.2
42   */
43  public class KerberosScheme extends GGSSchemeBase {
44  
45      private static final String KERBEROS_OID = "1.2.840.113554.1.2.2";
46  
47      public KerberosScheme(final boolean stripPort) {
48          super(stripPort);
49      }
50  
51      public KerberosScheme() {
52          super(false);
53      }
54  
55      public String getSchemeName() {
56          return "Kerberos";
57      }
58  
59      /**
60       * Produces KERBEROS authorization Header based on token created by
61       * processChallenge.
62       *
63       * @param credentials not used by the KERBEROS scheme.
64       * @param request The request being authenticated
65       *
66       * @throws AuthenticationException if authentication string cannot
67       *   be generated due to an authentication failure
68       *
69       * @return KERBEROS authentication Header
70       */
71      @Override
72      public Header authenticate(
73              final Credentials credentials,
74              final HttpRequest request,
75              final HttpContext context) throws AuthenticationException {
76          return super.authenticate(credentials, request, context);
77      }
78  
79      @Override
80      protected byte[] generateToken(final byte[] input, final String authServer) throws GSSException {
81          return generateGSSToken(input, new Oid(KERBEROS_OID), authServer);
82      }
83  
84      /**
85       * There are no valid parameters for KERBEROS authentication so this
86       * method always returns <code>null</code>.
87       *
88       * @return <code>null</code>
89       */
90      public String getParameter(final String name) {
91          Args.notNull(name, "Parameter name");
92          return null;
93      }
94  
95      /**
96       * The concept of an authentication realm is not supported by the Negotiate
97       * authentication scheme. Always returns <code>null</code>.
98       *
99       * @return <code>null</code>
100      */
101     public String getRealm() {
102         return null;
103     }
104 
105     /**
106      * Returns <tt>true</tt>. KERBEROS authentication scheme is connection based.
107      *
108      * @return <tt>true</tt>.
109      */
110     public boolean isConnectionBased() {
111         return true;
112     }
113 
114 }