org.jscsi.parser.TargetMessageParser Maven / Gradle / Ivy
/**
* Copyright (c) 2012, University of Konstanz, Distributed Systems Group All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification, are permitted provided that the
* following conditions are met: * Redistributions of source code must retain the above copyright notice, this list of
* conditions and the following disclaimer. * Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation and/or other materials provided with the
* distribution. * Neither the name of the University of Konstanz nor the names of its contributors may be used to
* endorse or promote products derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
* OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package org.jscsi.parser;
import org.jscsi.exception.InternetSCSIException;
import org.jscsi.utils.Utils;
/**
* TargetMessageParser
*
* This abstract class is the base class of all target message parsers defined in the iSCSI Protocol (RFC3720). This
* class defines some methods, which are common in all parsers to simplify the parsing process.
*
* @author Volker Wildi
*/
public abstract class TargetMessageParser extends AbstractMessageParser {
// --------------------------------------------------------------------------
// --------------------------------------------------------------------------
/** Status Sequence Number. */
protected int statusSequenceNumber;
/** Next Expected Commamd Sequence Number. */
protected int expectedCommandSequenceNumber;
/** Maximum Command Sequence Number. */
protected int maximumCommandSequenceNumber;
// --------------------------------------------------------------------------
// --------------------------------------------------------------------------
/**
* Default constructor, creates a new, empty TargetMessageParser object.
*
* @param initProtocolDataUnit The reference ProtocolDataUnit instance, which contains this
* TargetMessageParser subclass object.
*/
public TargetMessageParser (final ProtocolDataUnit initProtocolDataUnit) {
super(initProtocolDataUnit);
}
// --------------------------------------------------------------------------
// --------------------------------------------------------------------------
/** {@inheritDoc} */
@Override
public String getShortInfo () {
return "<- " + getClass().getSimpleName() + ": statSN: " + getStatusSequenceNumber() + ", expCmdSN: " + getExpectedCommandSequenceNumber() + ", maxCmdSN: " + getMaximumCommandSequenceNumber();
}
/** {@inheritDoc} */
@Override
public String toString () {
final StringBuilder sb = new StringBuilder(Constants.LOG_INITIAL_SIZE);
Utils.printField(sb, "StatusSequenceNumber", statusSequenceNumber, 1);
Utils.printField(sb, "ExpectedCommandSequenceNumber", expectedCommandSequenceNumber, 1);
Utils.printField(sb, "MaximumCommandSequenceNumber", maximumCommandSequenceNumber, 1);
return sb.toString();
}
/** {@inheritDoc} */
@Override
public void clear () {
super.clear();
statusSequenceNumber = 0;
expectedCommandSequenceNumber = 0;
maximumCommandSequenceNumber = 0;
}
// --------------------------------------------------------------------------
// --------------------------------------------------------------------------
/**
* This AbstractMessageParser instance affects the incrementation of the
* Expected Status Sequence Number.
*
* @return true, if the counter has to be incremented. Else false.
*/
@Override
public boolean incrementSequenceNumber () {
return true;
}
// --------------------------------------------------------------------------
// --------------------------------------------------------------------------
/**
* Next Expected Commamd Sequence Number from this Initiator ExpCmdSN is a Sequence Number that the
* target iSCSI returns to the initiator to acknowledge command reception. It is used to update a local variable
* with the same name. An ExpCmdSN equal to MaxCmdSN+1 indicates that the target cannot
* accept new commands.
*
* @return Expected Command Sequence Number.
*/
public final int getExpectedCommandSequenceNumber () {
return expectedCommandSequenceNumber;
}
/**
* Maximum Command Sequence Number from this Initiator MaxCmdSN is a Sequence Number that the target
* iSCSI returns to the initiator to indicate the maximum CmdSN the initiator can send. It is used to
* update a local variable with the same name. If MaxCmdSN is equal to ExpCmdSN-1, this
* indicates to the initiator that the target cannot receive any additional commands. When MaxCmdSN
* changes at the target while the target has no pending PDUs to convey this information to the initiator, it MUST
* generate a NOP-IN to carry the new MaxCmdSN.
*
* @return Maximum Command Sequence Number.
*/
public final int getMaximumCommandSequenceNumber () {
return maximumCommandSequenceNumber;
}
/**
* The Status Sequence Number (StatSN) is a Sequence Number that the target iSCSI layer generates per connection and
* that in turn, enables the initiator to acknowledge status reception. StatSN is incremented by
* 1 for every response/status sent on a connection except for responses sent as a result of a retry or
* SNACK. In the case of responses sent due to a retransmission request, the StatSN MUST be the same as
* the first time the PDU was sent unless the connection has since been restarted.
*
* @return Status Sequence Number.
*/
public final int getStatusSequenceNumber () {
return statusSequenceNumber;
}
/**
* Sets the Expected Command Sequence Number of this TargetMessageParser object to the given value.
*
* @param newExpectedCommandSequenceNumber The new Expected Command Sequence Number.
*/
public final void setExpectedCommandSequenceNumber (final int newExpectedCommandSequenceNumber) {
expectedCommandSequenceNumber = newExpectedCommandSequenceNumber;
}
/**
* Sets the Maximum Command Sequence Number of this TargetMessageParser object to the given value.
*
* @param newMaximumCommandSequenceNumber The new Maximum Command Sequence Number.
*/
public final void setMaximumCommandSequenceNumber (final int newMaximumCommandSequenceNumber) {
maximumCommandSequenceNumber = newMaximumCommandSequenceNumber;
}
/**
* Sets the Status Sequence Number of this TargetMessageParser object to the given value.
*
* @param newStatusSequenceNumber The new Status Sequence Number.
*/
public final void setStatusSequenceNumber (final int newStatusSequenceNumber) {
statusSequenceNumber = newStatusSequenceNumber;
}
// --------------------------------------------------------------------------
// --------------------------------------------------------------------------
/** {@inheritDoc} */
@Override
protected void deserializeBytes1to3 (final int line) throws InternetSCSIException {
Utils.isReserved(line);
}
/** {@inheritDoc} */
@Override
protected void deserializeBytes20to23 (final int line) throws InternetSCSIException {
Utils.isReserved(line);
}
/** {@inheritDoc} */
@Override
protected final void deserializeBytes24to27 (final int line) throws InternetSCSIException {
statusSequenceNumber = line;
}
/** {@inheritDoc} */
@Override
protected final void deserializeBytes28to31 (final int line) throws InternetSCSIException {
expectedCommandSequenceNumber = line;
}
/** {@inheritDoc} */
@Override
protected final void deserializeBytes32to35 (final int line) throws InternetSCSIException {
maximumCommandSequenceNumber = line;
}
/** {@inheritDoc} */
@Override
protected void deserializeBytes36to39 (final int line) throws InternetSCSIException {
Utils.isReserved(line);
}
/** {@inheritDoc} */
@Override
protected void deserializeBytes40to43 (final int line) throws InternetSCSIException {
Utils.isReserved(line);
}
/** {@inheritDoc} */
@Override
protected void deserializeBytes44to47 (final int line) throws InternetSCSIException {
Utils.isReserved(line);
}
// --------------------------------------------------------------------------
// --------------------------------------------------------------------------
/** {@inheritDoc} */
@Override
protected int serializeBytes1to3 () {
return Constants.RESERVED_INT;
}
/** {@inheritDoc} */
@Override
protected int serializeBytes20to23 () {
return Constants.RESERVED_INT;
}
/** {@inheritDoc} */
@Override
protected int serializeBytes24to27 () {
return statusSequenceNumber;
}
/** {@inheritDoc} */
@Override
protected int serializeBytes28to31 () {
return expectedCommandSequenceNumber;
}
/** {@inheritDoc} */
@Override
protected int serializeBytes32to35 () {
return maximumCommandSequenceNumber;
}
/** {@inheritDoc} */
@Override
protected int serializeBytes36to39 () {
return Constants.RESERVED_INT;
}
/** {@inheritDoc} */
@Override
protected int serializeBytes40to43 () {
return Constants.RESERVED_INT;
}
/** {@inheritDoc} */
@Override
protected int serializeBytes44to47 () {
return Constants.RESERVED_INT;
}
// --------------------------------------------------------------------------
// --------------------------------------------------------------------------
// --------------------------------------------------------------------------
// --------------------------------------------------------------------------
}