/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at
* trunk/opends/resource/legal-notices/OpenDS.LICENSE
* or https://OpenDS.dev.java.net/OpenDS.LICENSE.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at
* trunk/opends/resource/legal-notices/OpenDS.LICENSE. If applicable,
* add the following below this CDDL HEADER, with the fields enclosed
* by brackets "[]" replaced with your own identifying information:
* Portions Copyright [yyyy] [name of copyright owner]
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*
* Copyright 2006-2010 Sun Microsystems, Inc.
*/
package org.opends.server.protocols.ldap;
import static org.opends.messages.ProtocolMessages.*;
import static org.opends.server.loggers.AccessLogger.logConnect;
import static org.opends.server.loggers.debug.DebugLogger.*;
import static org.opends.server.util.StaticUtils.*;
import java.io.IOException;
import java.nio.channels.CancelledKeyException;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.SocketChannel;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import org.opends.messages.Message;
import org.opends.server.api.DirectoryThread;
import org.opends.server.api.ServerShutdownListener;
import org.opends.server.core.DirectoryServer;
import org.opends.server.loggers.ErrorLogger;
import org.opends.server.loggers.debug.DebugTracer;
import org.opends.server.protocols.asn1.ASN1ByteChannelReader;
import org.opends.server.protocols.asn1.ASN1Exception;
import org.opends.server.types.DebugLogLevel;
import org.opends.server.types.DisconnectReason;
import org.opends.server.types.InitializationException;
import org.opends.server.types.LDAPException;
/**
* This class defines an LDAP request handler, which is associated with an LDAP
* connection handler and is responsible for reading and decoding any requests
* that LDAP clients may send to the server. Multiple request handlers may be
* used in conjunction with a single connection handler for better performance
* and scalability.
*/
public class LDAPRequestHandler
extends DirectoryThread
implements ServerShutdownListener
{
/**
* The tracer object for the debug logger.
*/
private static final DebugTracer TRACER = getTracer();
// Indicates whether the Directory Server is in the process of shutting down.
private volatile boolean shutdownRequested = false;
// The current set of selection keys.
private volatile SelectionKey[] keys = new SelectionKey[0];
// The queue that will be used to hold the set of pending connections that
// need to be registered with the selector.
// TODO: revisit, see Issue 4202.
private List<LDAPClientConnection> pendingConnections =
new LinkedList<LDAPClientConnection>();
// Lock object for synchronizing access to the pending connections queue.
private final Object pendingConnectionsLock = new Object();
// The list of connections ready for request processing.
private LinkedList<LDAPClientConnection> readyConnections =
new LinkedList<LDAPClientConnection>();
// The selector that will be used to monitor the client connections.
private final Selector selector;
// The name to use for this request handler.
private final String handlerName;
/**
* Creates a new LDAP request handler that will be associated with the
* provided connection handler.
*
* @param connectionHandler The LDAP connection handler with which this
* request handler is associated.
* @param requestHandlerID The integer value that may be used to distingush
* this request handler from others associated with
* the same connection handler.
*
* @throws InitializationException If a problem occurs while initializing
* this request handler.
*/
public LDAPRequestHandler(LDAPConnectionHandler connectionHandler,
int requestHandlerID)
throws InitializationException
{
super("LDAP Request Handler " + requestHandlerID +
" for connection handler " + connectionHandler.toString());
handlerName = getName();
try
{
selector = Selector.open();
}
catch (Exception e)
{
if (debugEnabled())
{
TRACER.debugCaught(DebugLogLevel.ERROR, e);
}
Message message = ERR_LDAP_REQHANDLER_OPEN_SELECTOR_FAILED.get(
handlerName, String.valueOf(e));
throw new InitializationException(message, e);
}
try
{
// Check to see if we get an error while trying to perform a select. If
// we do, then it's likely CR 6322825 and the server won't be able to
// handle LDAP requests in its current state.
selector.selectNow();
}
catch (IOException ioe)
{
StackTraceElement[] stackElements = ioe.getStackTrace();
if ((stackElements != null) && (stackElements.length > 0))
{
StackTraceElement ste = stackElements[0];
if (ste.getClassName().equals("sun.nio.ch.DevPollArrayWrapper") &&
(ste.getMethodName().indexOf("poll") >= 0) &&
ioe.getMessage().equalsIgnoreCase("Invalid argument"))
{
Message message = ERR_LDAP_REQHANDLER_DETECTED_JVM_ISSUE_CR6322825.
get(String.valueOf(ioe));
throw new InitializationException(message, ioe);
}
}
}
}
/**
* Operates in a loop, waiting for client requests to arrive and ensuring that
* they are processed properly.
*/
@Override
public void run()
{
// Operate in a loop until the server shuts down. Each time through the
// loop, check for new requests, then check for new connections.
while (!shutdownRequested)
{
LDAPClientConnection readyConnection = null;
while ((readyConnection = readyConnections.poll()) != null)
{
try
{
ASN1ByteChannelReader asn1Reader = readyConnection.getASN1Reader();
boolean ldapMessageProcessed = false;
while (true)
{
if (asn1Reader.elementAvailable())
{
if (!ldapMessageProcessed)
{
if (readyConnection.processLDAPMessage(
LDAPReader.readMessage(asn1Reader)))
{
ldapMessageProcessed = true;
}
else
{
break;
}
}
else
{
readyConnections.add(readyConnection);
break;
}
}
else
{
if (readyConnection.processDataRead() <= 0)
{
break;
}
}
}
}
catch (ASN1Exception e)
{
if (debugEnabled())
{
TRACER.debugCaught(DebugLogLevel.ERROR, e);
}
readyConnection.disconnect(DisconnectReason.PROTOCOL_ERROR, true,
e.getMessageObject());
}
catch (LDAPException e)
{
if (debugEnabled())
{
TRACER.debugCaught(DebugLogLevel.ERROR, e);
}
readyConnection.disconnect(DisconnectReason.PROTOCOL_ERROR, true,
e.getMessageObject());
}
catch (Exception e)
{
if (debugEnabled())
{
TRACER.debugCaught(DebugLogLevel.ERROR, e);
}
readyConnection.disconnect(DisconnectReason.PROTOCOL_ERROR, true,
Message.raw(e.toString()));
}
}
// Check to see if we have any pending connections that need to be
// registered with the selector.
List<LDAPClientConnection> tmp = null;
synchronized (pendingConnectionsLock)
{
if (!pendingConnections.isEmpty())
{
tmp = pendingConnections;
pendingConnections = new LinkedList<LDAPClientConnection>();
}
}
if (tmp != null)
{
for (LDAPClientConnection c : tmp)
{
try
{
SocketChannel socketChannel = c.getSocketChannel();
socketChannel.configureBlocking(false);
socketChannel.register(selector, SelectionKey.OP_READ, c);
logConnect(c);
}
catch (Exception e)
{
if (debugEnabled())
{
TRACER.debugCaught(DebugLogLevel.ERROR, e);
}
c.disconnect(DisconnectReason.SERVER_ERROR, true,
ERR_LDAP_REQHANDLER_CANNOT_REGISTER.get(handlerName,
String.valueOf(e)));
}
}
}
// Create a copy of the selection keys which can be used in a
// thread-safe manner by getClientConnections. This copy is only
// updated once per loop, so may not be accurate.
keys = selector.keys().toArray(new SelectionKey[0]);
int selectedKeys = 0;
try
{
// We timeout every second so that we can refresh the key list.
selectedKeys = selector.select(1000);
}
catch (Exception e)
{
if (debugEnabled())
{
TRACER.debugCaught(DebugLogLevel.ERROR, e);
}
// FIXME -- Should we do something else with this?
}
if (shutdownRequested)
{
// Avoid further processing and disconnect all clients.
break;
}
if (selectedKeys > 0)
{
Iterator<SelectionKey> iterator = selector.selectedKeys().iterator();
while (iterator.hasNext())
{
SelectionKey key = iterator.next();
try
{
if (key.isReadable())
{
LDAPClientConnection clientConnection = null;
try
{
clientConnection = (LDAPClientConnection) key.attachment();
try
{
int readResult = clientConnection.processDataRead();
if (readResult < 0)
{
key.cancel();
}
if (readResult > 0) {
readyConnections.add(clientConnection);
}
}
catch (Exception e)
{
if (debugEnabled())
{
TRACER.debugCaught(DebugLogLevel.ERROR, e);
}
// Some other error occurred while we were trying to read data
// from the client.
// FIXME -- Should we log this?
key.cancel();
clientConnection.disconnect(DisconnectReason.SERVER_ERROR,
false, null);
}
}
catch (Exception e)
{
if (debugEnabled())
{
TRACER.debugCaught(DebugLogLevel.ERROR, e);
}
// We got some other kind of error. If nothing else, cancel the
// key, but if the client connection is available then
// disconnect it as well.
key.cancel();
if (clientConnection != null)
{
clientConnection.disconnect(DisconnectReason.SERVER_ERROR,
false, null);
}
}
}
else if (! key.isValid())
{
key.cancel();
}
}
catch (CancelledKeyException cke)
{
if (debugEnabled())
{
TRACER.debugCaught(DebugLogLevel.ERROR, cke);
}
// This could happen if a connection was closed between the time
// that select returned and the time that we try to access the
// associated channel. If that was the case, we don't need to do
// anything.
}
catch (Exception e)
{
if (debugEnabled())
{
TRACER.debugCaught(DebugLogLevel.ERROR, e);
}
// This should not happen, and it would have caused our reader
// thread to die. Log a severe error.
Message message = ERR_LDAP_REQHANDLER_UNEXPECTED_SELECT_EXCEPTION.
get(getName(), getExceptionMessage(e));
ErrorLogger.logError(message);
}
finally
{
if (!key.isValid())
{
// Help GC - release the connection.
key.attach(null);
}
iterator.remove();
}
}
}
}
// Disconnect all active connections.
SelectionKey[] keyArray = selector.keys().toArray(new SelectionKey[0]);
for (SelectionKey key : keyArray)
{
LDAPClientConnection c = (LDAPClientConnection) key.attachment();
try
{
key.channel().close();
}
catch (Exception e)
{
if (debugEnabled())
{
TRACER.debugCaught(DebugLogLevel.ERROR, e);
}
}
try
{
key.cancel();
}
catch (Exception e)
{
if (debugEnabled())
{
TRACER.debugCaught(DebugLogLevel.ERROR, e);
}
}
try
{
c.disconnect(DisconnectReason.SERVER_SHUTDOWN, true,
ERR_LDAP_REQHANDLER_DEREGISTER_DUE_TO_SHUTDOWN.get());
}
catch (Exception e)
{
if (debugEnabled())
{
TRACER.debugCaught(DebugLogLevel.ERROR, e);
}
}
}
// Disconnect all pending connections.
synchronized (pendingConnectionsLock)
{
for (LDAPClientConnection c : pendingConnections)
{
try
{
c.disconnect(DisconnectReason.SERVER_SHUTDOWN, true,
ERR_LDAP_REQHANDLER_DEREGISTER_DUE_TO_SHUTDOWN.get());
}
catch (Exception e)
{
if (debugEnabled())
{
TRACER.debugCaught(DebugLogLevel.ERROR, e);
}
}
}
}
}
/**
* Registers the provided client connection with this request
* handler so that any requests received from that client will be
* processed.
*
* @param clientConnection
* The client connection to be registered with this request
* handler.
* @return <CODE>true</CODE> if the client connection was properly
* registered with this request handler, or
* <CODE>false</CODE> if not.
*/
public boolean registerClient(LDAPClientConnection clientConnection)
{
// FIXME -- Need to check if the maximum client limit has been reached.
// If the server is in the process of shutting down, then we don't want to
// accept it.
if (shutdownRequested)
{
clientConnection.disconnect(DisconnectReason.SERVER_SHUTDOWN, true,
ERR_LDAP_REQHANDLER_REJECT_DUE_TO_SHUTDOWN.get());
return false;
}
// Try to add the new connection to the queue. If it succeeds, then wake
// up the selector so it will be picked up right away. Otherwise,
// disconnect the client.
synchronized (pendingConnectionsLock)
{
pendingConnections.add(clientConnection);
}
selector.wakeup();
return true;
}
/**
* Retrieves the set of all client connections that are currently registered
* with this request handler.
*
* @return The set of all client connections that are currently registered
* with this request handler.
*/
public Collection<LDAPClientConnection> getClientConnections()
{
ArrayList<LDAPClientConnection> connList =
new ArrayList<LDAPClientConnection>(keys.length);
for (SelectionKey key : keys)
{
LDAPClientConnection c = (LDAPClientConnection) key.attachment();
// If the client has disconnected the attachment may be null.
if (c != null)
{
connList.add(c);
}
}
return connList;
}
/**
* Retrieves the human-readable name for this shutdown listener.
*
* @return The human-readable name for this shutdown listener.
*/
public String getShutdownListenerName()
{
return handlerName;
}
/**
* Causes this request handler to register itself as a shutdown listener with
* the Directory Server. This must be called if the connection handler is
* shut down without closing all associated connections, otherwise the thread
* would not be stopped by the server.
*/
public void registerShutdownListener()
{
DirectoryServer.registerShutdownListener(this);
}
/**
* Indicates that the Directory Server has received a request to stop running
* and that this shutdown listener should take any action necessary to prepare
* for it.
*
* @param reason The human-readable reason for the shutdown.
*/
public void processServerShutdown(Message reason)
{
shutdownRequested = true;
selector.wakeup();
}
}