1 /**
2 * Copyright (c) 2012, University of Konstanz, Distributed Systems Group All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without modification, are permitted provided that the
5 * following conditions are met: * Redistributions of source code must retain the above copyright notice, this list of
6 * conditions and the following disclaimer. * Redistributions in binary form must reproduce the above copyright notice,
7 * this list of conditions and the following disclaimer in the documentation and/or other materials provided with the
8 * distribution. * Neither the name of the University of Konstanz nor the names of its contributors may be used to
9 * endorse or promote products derived from this software without specific prior written permission.
10 *
11 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
12 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
13 * DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
14 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
15 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
16 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
17 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
18 */
19 package org.jscsi.initiator.connection;
20
21
22 import java.io.IOException;
23 import java.net.InetSocketAddress;
24 import java.security.DigestException;
25 import java.util.Queue;
26
27 import org.jscsi.exception.InternetSCSIException;
28 import org.jscsi.exception.NoSuchSessionException;
29 import org.jscsi.exception.OperationalTextKeyException;
30 import org.jscsi.initiator.Configuration;
31 import org.jscsi.initiator.connection.state.IState;
32 import org.jscsi.parser.ProtocolDataUnit;
33 import org.jscsi.parser.datasegment.OperationalTextKey;
34 import org.jscsi.parser.datasegment.SettingsMap;
35 import org.jscsi.utils.SerialArithmeticNumber;
36 import org.slf4j.Logger;
37 import org.slf4j.LoggerFactory;
38
39
40 /**
41 * <h1>AbsConnection</h1>
42 * <p/>
43 * This abstract class represents a connection, which is used in the iSCSI Standard (RFC3720). Such a connection is
44 * directed from the initiator to the target. It is used in Sessions.
45 *
46 * @author Volker Wildi, University of Konstanz
47 * @author Patrice Matthias Brend'amour, University of Konstanz
48 * @author Sebastian Graf, University of Konstanz
49 */
50 public final class Connection {
51
52 // --------------------------------------------------------------------------
53 // --------------------------------------------------------------------------
54
55 /** The logger interface. */
56 private static final Logger LOGGER = LoggerFactory.getLogger(Connection.class);
57
58 // --------------------------------------------------------------------------
59 // --------------------------------------------------------------------------
60
61 /**
62 * The <code>Session</code> instance, which contains this <code>Connection</code> instance.
63 */
64 private final Session referenceSession;
65
66 /** The <code>Configuration</code> instance for this connection. */
67 private final Configuration configuration;
68
69 /** The current state of this connection. */
70 private IState state;
71
72 /**
73 * The ID of this connection. This must be unique within a <code>Session</code>.
74 */
75 private final short connectionID;
76
77 /**
78 * The Expected Status Sequence Number, which is expected to received from the target within this connection.
79 */
80 private final SerialArithmeticNumber expectedStatusSequenceNumber;
81
82 // --------------------------------------------------------------------------
83 // --------------------------------------------------------------------------
84
85 /**
86 * The worker caller, which handles the transmission of the packages over the network.
87 */
88 private final SenderWorker senderReceiver;
89
90 /**
91 * Method to create and return a new, empty <code>Connection</code> object with the configured layer of threading.
92 *
93 * @param session Reference to the <code>AbsSession</code> object, which contains this connection.
94 * @param initConfiguration The configuration to use within this connection.
95 * @param inetAddress The <code>InetSocketAddress</code> to which this connection should established.
96 * @param initConnectionID The ID of this connection.
97 * @throws Exception If any error occurs.
98 */
99
100 public Connection (final Session session, final Configuration initConfiguration, final InetSocketAddress inetAddress, final short initConnectionID) throws Exception {
101
102 senderReceiver = new SenderWorker(this, inetAddress);
103
104 configuration = initConfiguration;
105 connectionID = initConnectionID;
106
107 referenceSession = session;
108 expectedStatusSequenceNumber = new SerialArithmeticNumber();
109
110 }
111
112 /**
113 * Updates all entries of the given response key-values with the stored settings of this instance.
114 *
115 * @param response The settings of the response.
116 * @throws NoSuchSessionException if a session with this target name is not open.
117 */
118 public final void update (final SettingsMap response) throws NoSuchSessionException {
119
120 configuration.update(referenceSession.getTargetName(), connectionID, response);
121 }
122
123 /**
124 * Returns the value of the given parameter, which is parsed to an <code>boolean</code>.
125 *
126 * @param textKey The name of the parameter.
127 * @return The <code>boolean</code> value of this parameter. So if the value is equal to <code>Yes</code>, then
128 * <code>true</code> will be returned. Else <code>false</code> is returned.
129 * @throws OperationalTextKeyException If the given parameter cannot be found.
130 */
131 public final boolean getSettingAsBoolean (final OperationalTextKey textKey) throws OperationalTextKeyException {
132 return getSetting(textKey).compareTo("Yes") == 0;
133 }
134
135 /**
136 * Returns the value of the given parameter, which is parsed to an <code>integer</code>.
137 *
138 * @param textKey The name of the parameter.
139 * @return The <code>integer</code> value of this parameter.
140 * @throws OperationalTextKeyException If the given parameter cannot be found.
141 */
142 public final int getSettingAsInt (final OperationalTextKey textKey) throws OperationalTextKeyException {
143
144 return Integer.parseInt(getSetting(textKey));
145 }
146
147 /**
148 * Returns the value of the given parameter as <code>String</code>.
149 *
150 * @param textKey The name of the parameter.
151 * @return The value of this parameter.
152 * @throws OperationalTextKeyException If the given parameter cannot be found.
153 */
154 public final String getSetting (final OperationalTextKey textKey) throws OperationalTextKeyException {
155
156 return configuration.getSetting(referenceSession.getTargetName(), connectionID, textKey);
157 }
158
159 /**
160 * Returns the settings of the given session and connection.
161 *
162 * @return The settings of this specific connection.
163 */
164 public final SettingsMap getSettings () {
165
166 return configuration.getSettings(referenceSession.getTargetName(), connectionID);
167 }
168
169 // --------------------------------------------------------------------------
170 // --------------------------------------------------------------------------
171
172 /**
173 * Increments the Expected Status Sequence Number as defined in RFC1982 where <code>SERIAL_BITS = 32</code>.
174 */
175 public final void incrementExpectedStatusSequenceNumber () {
176
177 expectedStatusSequenceNumber.increment();
178 }
179
180 /**
181 * Returns the Expected Status Sequence Number of this <code>Connection</code> object.
182 *
183 * @return The current Expected Status Sequence Number.
184 */
185 public final SerialArithmeticNumber getExpectedStatusSequenceNumber () {
186
187 return expectedStatusSequenceNumber;
188 }
189
190 /**
191 * Sets the expected Status Sequence Number to the given one from the leading Login Response.
192 *
193 * @param newExpectedStatusSequenceNumber The new value.
194 */
195 public final void setExpectedStatusSequenceNumber (final int newExpectedStatusSequenceNumber) {
196
197 expectedStatusSequenceNumber.setValue(newExpectedStatusSequenceNumber);
198
199 LOGGER.trace("Set ExpStatSN to " + expectedStatusSequenceNumber);
200 }
201
202 // --------------------------------------------------------------------------
203 // --------------------------------------------------------------------------
204
205 /**
206 * Switch to the new state. Start point of the state pattern. All states are computed one after another.
207 *
208 * @param newState The new state.
209 * @throws InternetSCSIException of any kind
210 */
211 public final void nextState (final IState newState) throws InternetSCSIException {
212
213 this.state = newState;
214 if (this.state != null) {
215 do {
216 this.state.execute();
217 LOGGER.info("State is following: " + this.state.nextStateFollowing());
218 } while (this.state.nextStateFollowing());
219 }
220
221 }
222
223 /**
224 * Returns the current state of this connection.
225 *
226 * @return The current <code>IState</code> instance of this <code>Connection</code> instance.
227 */
228 public final IState getState () {
229
230 return state;
231 }
232
233 /**
234 * Returns the session, which contains this connection instance.
235 *
236 * @return The parent session instance.
237 */
238 public final Session getSession () {
239
240 return referenceSession;
241 }
242
243 /**
244 * Returns the ID of this <code>Connection</code> object.
245 *
246 * @return The connection ID.
247 */
248 public final short getConnectionID () {
249
250 return connectionID;
251 }
252
253 // --------------------------------------------------------------------------
254 // --------------------------------------------------------------------------
255
256 /**
257 * This method does all the necessary steps, which are needed when a connection should be closed.
258 *
259 * @throws IOException if an I/O error occurs.
260 */
261 public final void close () throws IOException {
262
263 senderReceiver.close();
264 LOGGER.debug("Connection with ID " + connectionID + " closed.");
265 }
266
267 /**
268 * Enqueue this protocol data unit to the end of the sending queue.
269 *
270 * @param protocolDataUnit The protocol data unit to add.
271 * @throws InternetSCSIException for nearly everything
272 */
273 public final void send (final ProtocolDataUnit protocolDataUnit) throws InternetSCSIException {
274
275 try {
276 senderReceiver.sendOverWire(protocolDataUnit);
277 } catch (IOException e) {
278 throw new InternetSCSIException(e);
279 } catch (InterruptedException e) {
280 throw new InternetSCSIException(e);
281 }
282 }
283
284 /**
285 * Enqueue all protocol data units to the end of the sending queue.
286 *
287 * @param protocolDataUnits The list with all protocol data units to add.
288 * @throws InternetSCSIException for nearly everything
289 */
290 public final void send (final Queue<ProtocolDataUnit> protocolDataUnits) throws InternetSCSIException {
291
292 for (final ProtocolDataUnit unit : protocolDataUnits) {
293 send(unit);
294 }
295 }
296
297 /**
298 * Reads one <code>ProtocolDataUnit</code> instance from the <code>receivingQueue</code>.
299 *
300 * @return An instance of a <code>ProtocolDataUnit</code>.
301 * @throws InternetSCSIException for nearly everything
302 */
303 public final ProtocolDataUnit receive () throws InternetSCSIException {
304
305 try {
306 return senderReceiver.receiveFromWire();
307 } catch (DigestException e) {
308 throw new InternetSCSIException(e);
309 } catch (IOException e) {
310 throw new InternetSCSIException(e);
311 }
312 }
313
314 // --------------------------------------------------------------------------
315 // --------------------------------------------------------------------------
316 // --------------------------------------------------------------------------
317 // --------------------------------------------------------------------------
318 }