1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 *
19 */
20 package org.apache.directory.api.ldap.model.message.extended;
21
22
23 import org.apache.directory.api.i18n.I18n;
24 import org.apache.directory.api.ldap.model.message.ExtendedResponseImpl;
25 import org.apache.directory.api.ldap.model.message.ResultCodeEnum;
26
27
28 /**
29 * An extended operation intended for notifying clients of upcoming
30 * disconnection. Here's what <a
31 * href="http://www.faqs.org/rfcs/rfc2251.html">RFC 2251</a> has to say about
32 * it:
33 *
34 * <pre>
35 * Section 4.1.1 (Small snippet on sending NoD)
36 *
37 * If the server receives a PDU from the client in which the LDAPMessage
38 * SEQUENCE tag cannot be recognized, the messageID cannot be parsed,
39 * the tag of the protocolOp is not recognized as a request, or the
40 * encoding structures or lengths of data fields are found to be
41 * incorrect, then the server MUST return the notice of disconnection
42 * described in section 4.4.1, with resultCode protocolError, and
43 * immediately close the connection. In other cases that the server
44 * cannot parse the request received by the client, the server MUST
45 * return an appropriate response to the request, with the resultCode
46 * set to protocolError.
47 *
48 * ...
49 *
50 * 4.4. Unsolicited Notification
51 *
52 * An unsolicited notification is an LDAPMessage sent from the server to
53 * the client which is not in response to any LDAPMessage received by
54 * the server. It is used to signal an extraordinary condition in the
55 * server or in the connection between the client and the server. The
56 * notification is of an advisory nature, and the server will not expect
57 * any response to be returned from the client.
58 *
59 * The unsolicited notification is structured as an LDAPMessage in which
60 * the messageID is 0 and protocolOp is of the extendedResp form. The
61 * responseName field of the ExtendedResponse is present. The LDAPOID
62 * value MUST be unique for this notification, and not be used in any
63 * other situation.
64 *
65 * One unsolicited notification is defined in this document.
66 *
67 * 4.4.1. Notice of Disconnection
68 *
69 * This notification may be used by the server to advise the client that
70 * the server is about to close the connection due to an error
71 * condition. Note that this notification is NOT a response to an
72 * unbind requested by the client: the server MUST follow the procedures
73 * of section 4.3. This notification is intended to assist clients in
74 * distinguishing between an error condition and a transient network
75 * failure. As with a connection close due to network failure, the
76 * client MUST NOT assume that any outstanding requests which modified
77 * the directory have succeeded or failed.
78 *
79 * The responseName is 1.3.6.1.4.1.1466.20036, the response field is
80 * absent, and the resultCode is used to indicate the reason for the
81 * disconnection.
82 *
83 * The following resultCode values are to be used in this notification:
84 *
85 * - protocolError: The server has received data from the client in
86 * which the LDAPMessage structure could not be parsed.
87 *
88 * - strongAuthRequired: The server has detected that an established
89 * underlying security association protecting communication between
90 * the client and server has unexpectedly failed or been compromised.
91 *
92 * - unavailable: This server will stop accepting new connections and
93 * operations on all existing connections, and be unavailable for an
94 * extended period of time. The client may make use of an alternative
95 * server.
96 *
97 * After sending this notice, the server MUST close the connection.
98 * After receiving this notice, the client MUST NOT transmit any further
99 * on the connection, and may abruptly close the connection.
100 * </pre>
101 *
102 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
103 */
104 public final class NoticeOfDisconnect extends ExtendedResponseImpl
105 {
106 /** The OID of the NotiveOfDisconnect extended operation. */
107 public static final String EXTENSION_OID = "1.3.6.1.4.1.1466.20036";
108
109 /** The empty response */
110 private static final byte[] EMPTY_RESPONSE = new byte[0];
111
112 /** The single instance with unavailable result code. */
113 public static final NoticeOfDisconnect UNAVAILABLE = new NoticeOfDisconnect( ResultCodeEnum.UNAVAILABLE );
114
115 /** The single instance with protocolError result code. */
116 public static final NoticeOfDisconnect PROTOCOLERROR = new NoticeOfDisconnect( ResultCodeEnum.PROTOCOL_ERROR );
117
118 /** The single instance with strongAuthRequired result code. */
119 public static final NoticeOfDisconnect STRONGAUTHREQUIRED = new NoticeOfDisconnect(
120 ResultCodeEnum.STRONG_AUTH_REQUIRED );
121
122
123 /**
124 * Creates a new instance of NoticeOfDisconnect.
125 */
126 private NoticeOfDisconnect( ResultCodeEnum rcode )
127 {
128 super( 0, EXTENSION_OID );
129
130 switch ( rcode )
131 {
132 case UNAVAILABLE:
133 break;
134
135 case PROTOCOL_ERROR:
136 break;
137
138 case STRONG_AUTH_REQUIRED:
139 break;
140
141 default:
142 throw new IllegalArgumentException( I18n.err( I18n.ERR_04166, ResultCodeEnum.UNAVAILABLE,
143 ResultCodeEnum.PROTOCOL_ERROR, ResultCodeEnum.STRONG_AUTH_REQUIRED ) );
144 }
145
146 super.getLdapResult().setDiagnosticMessage( rcode.toString() + ": The server will disconnect!" );
147 super.getLdapResult().setMatchedDn( null );
148 super.getLdapResult().setResultCode( rcode );
149 }
150
151
152 // ------------------------------------------------------------------------
153 // ExtendedResponse Interface Method Implementations
154 // ------------------------------------------------------------------------
155
156 /**
157 * Gets the reponse OID specific encoded response values.
158 *
159 * @return the response specific encoded response values.
160 */
161 public byte[] getResponse()
162 {
163 return EMPTY_RESPONSE;
164 }
165
166
167 /**
168 * Sets the response OID specific encoded response values.
169 *
170 * @param value the response specific encoded response values.
171 */
172 public void setResponse( byte[] value )
173 {
174 throw new UnsupportedOperationException( I18n.err( I18n.ERR_04173 ) );
175 }
176
177
178 /**
179 * Gets the OID uniquely identifying this extended response (a.k.a. its
180 * name).
181 *
182 * @return the OID of the extended response type.
183 */
184 public String getResponseName()
185 {
186 return EXTENSION_OID;
187 }
188
189
190 /**
191 * Sets the OID uniquely identifying this extended response (a.k.a. its
192 * name).
193 *
194 * @param oid
195 * the OID of the extended response type.
196 */
197 public void setResponseName( String oid )
198 {
199 throw new UnsupportedOperationException( I18n.err( I18n.ERR_04168, EXTENSION_OID ) );
200 }
201
202
203 /**
204 * {@inheritDoc}
205 */
206 @Override
207 public int hashCode()
208 {
209 int hash = 37;
210 // Seems simple but look at the equals() method ...
211 hash = hash * 17 + getClass().getName().hashCode();
212
213 return hash;
214 }
215
216
217 /**
218 * {@inheritDoc}
219 */
220 @Override
221 public boolean equals( Object obj )
222 {
223 if ( obj == this )
224 {
225 return true;
226 }
227
228 return ( obj instanceof NoticeOfDisconnect );
229 }
230 }