001 /*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements. See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership. The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License. You may obtain a copy of the License at
009 *
010 * http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied. See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 *
019 */
020 package org.apache.directory.shared.ldap.message.extended;
021
022
023 import org.apache.directory.shared.i18n.I18n;
024 import org.apache.directory.shared.ldap.message.ExtendedResponseImpl;
025 import org.apache.directory.shared.ldap.message.ResultCodeEnum;
026
027
028 /**
029 * An extended operation intended for notifying clients of upcoming
030 * disconnection. Here's what <a
031 * href="http://www.faqs.org/rfcs/rfc2251.html">RFC 2251</a> has to say about
032 * it:
033 *
034 * <pre>
035 * Section 4.1.1 (Small snippet on sending NoD)
036 *
037 * If the server receives a PDU from the client in which the LDAPMessage
038 * SEQUENCE tag cannot be recognized, the messageID cannot be parsed,
039 * the tag of the protocolOp is not recognized as a request, or the
040 * encoding structures or lengths of data fields are found to be
041 * incorrect, then the server MUST return the notice of disconnection
042 * described in section 4.4.1, with resultCode protocolError, and
043 * immediately close the connection. In other cases that the server
044 * cannot parse the request received by the client, the server MUST
045 * return an appropriate response to the request, with the resultCode
046 * set to protocolError.
047 *
048 * ...
049 *
050 * 4.4. Unsolicited Notification
051 *
052 * An unsolicited notification is an LDAPMessage sent from the server to
053 * the client which is not in response to any LDAPMessage received by
054 * the server. It is used to signal an extraordinary condition in the
055 * server or in the connection between the client and the server. The
056 * notification is of an advisory nature, and the server will not expect
057 * any response to be returned from the client.
058 *
059 * The unsolicited notification is structured as an LDAPMessage in which
060 * the messageID is 0 and protocolOp is of the extendedResp form. The
061 * responseName field of the ExtendedResponse is present. The LDAPOID
062 * value MUST be unique for this notification, and not be used in any
063 * other situation.
064 *
065 * One unsolicited notification is defined in this document.
066 *
067 * 4.4.1. Notice of Disconnection
068 *
069 * This notification may be used by the server to advise the client that
070 * the server is about to close the connection due to an error
071 * condition. Note that this notification is NOT a response to an
072 * unbind requested by the client: the server MUST follow the procedures
073 * of section 4.3. This notification is intended to assist clients in
074 * distinguishing between an error condition and a transient network
075 * failure. As with a connection close due to network failure, the
076 * client MUST NOT assume that any outstanding requests which modified
077 * the directory have succeeded or failed.
078 *
079 * The responseName is 1.3.6.1.4.1.1466.20036, the response field is
080 * absent, and the resultCode is used to indicate the reason for the
081 * disconnection.
082 *
083 * The following resultCode values are to be used in this notification:
084 *
085 * - protocolError: The server has received data from the client in
086 * which the LDAPMessage structure could not be parsed.
087 *
088 * - strongAuthRequired: The server has detected that an established
089 * underlying security association protecting communication between
090 * the client and server has unexpectedly failed or been compromised.
091 *
092 * - unavailable: This server will stop accepting new connections and
093 * operations on all existing connections, and be unavailable for an
094 * extended period of time. The client may make use of an alternative
095 * server.
096 *
097 * After sending this notice, the server MUST close the connection.
098 * After receiving this notice, the client MUST NOT transmit any further
099 * 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 * @version $Rev: 912436 $
104 */
105 public class NoticeOfDisconnect extends ExtendedResponseImpl
106 {
107 private static final long serialVersionUID = -4682291068700593492L;
108
109 public static final String EXTENSION_OID = "1.3.6.1.4.1.1466.20036";
110
111 private static final byte[] EMPTY_RESPONSE = new byte[0];
112
113 public static final NoticeOfDisconnect UNAVAILABLE = new NoticeOfDisconnect( ResultCodeEnum.UNAVAILABLE );
114
115 public static final NoticeOfDisconnect PROTOCOLERROR = new NoticeOfDisconnect( ResultCodeEnum.PROTOCOL_ERROR );
116
117 public static final NoticeOfDisconnect STRONGAUTHREQUIRED = new NoticeOfDisconnect( ResultCodeEnum.STRONG_AUTH_REQUIRED );
118
119
120 private NoticeOfDisconnect( ResultCodeEnum rcode )
121 {
122 super( 0, EXTENSION_OID );
123
124 switch ( rcode )
125 {
126 case UNAVAILABLE :
127 break;
128
129 case PROTOCOL_ERROR :
130 break;
131
132 case STRONG_AUTH_REQUIRED :
133 break;
134
135 default:
136 throw new IllegalArgumentException( I18n.err( I18n.ERR_04166, ResultCodeEnum.UNAVAILABLE,
137 ResultCodeEnum.PROTOCOL_ERROR, ResultCodeEnum.STRONG_AUTH_REQUIRED ) );
138 }
139
140 super.getLdapResult().setErrorMessage( rcode.toString() + ": The server will disconnect!" );
141 super.getLdapResult().setMatchedDn( null );
142 super.getLdapResult().setResultCode( rcode );
143 }
144
145
146 // ------------------------------------------------------------------------
147 // ExtendedResponse Interface Method Implementations
148 // ------------------------------------------------------------------------
149
150
151 /**
152 * Gets the reponse OID specific encoded response values.
153 *
154 * @return the response specific encoded response values.
155 */
156 public byte[] getResponse()
157 {
158 return EMPTY_RESPONSE;
159 }
160
161
162 /**
163 * Sets the reponse OID specific encoded response values.
164 *
165 * @param value
166 * the response specific encoded response values.
167 */
168 public void setResponse( byte[] value )
169 {
170 throw new UnsupportedOperationException( I18n.err( I18n.ERR_04173 ) );
171 }
172
173
174 /**
175 * Gets the OID uniquely identifying this extended response (a.k.a. its
176 * name).
177 *
178 * @return the OID of the extended response type.
179 */
180 public String getResponseName()
181 {
182 return EXTENSION_OID;
183 }
184
185
186 /**
187 * Sets the OID uniquely identifying this extended response (a.k.a. its
188 * name).
189 *
190 * @param oid
191 * the OID of the extended response type.
192 */
193 public void setResponseName( String oid )
194 {
195 throw new UnsupportedOperationException( I18n.err( I18n.ERR_04168, EXTENSION_OID ) );
196 }
197
198
199 public boolean equals( Object obj )
200 {
201 if ( obj == this )
202 {
203 return true;
204 }
205
206 if ( obj instanceof NoticeOfDisconnect )
207 {
208 return true;
209 }
210
211 return false;
212 }
213 }