/*
* Copyright (c) 2002, 2015, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package javax.management.remote.rmi;
import com.sun.jmx.remote.internal.ArrayNotificationBuffer;
import com.sun.jmx.remote.internal.NotificationBuffer;
import com.sun.jmx.remote.security.JMXPluggableAuthenticator;
import com.sun.jmx.remote.util.ClassLogger;
import java.io.Closeable;
import java.io.IOException;
import java.lang.ref.WeakReference;
import java.rmi.Remote;
import java.rmi.server.RemoteServer;
import java.rmi.server.ServerNotActiveException;
import java.security.Principal;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import javax.management.MBeanServer;
import javax.management.remote.JMXAuthenticator;
import javax.management.remote.JMXConnectorServer;
import javax.security.auth.Subject;
/**
* <p>An RMI object representing a connector server. Remote clients
* can make connections using the {@link #newClient(Object)} method. This
* method returns an RMI object representing the connection.</p>
*
* <p>User code does not usually reference this class directly.
* RMI connection servers are usually created with the class {@link
* RMIConnectorServer}. Remote clients usually create connections
* either with {@link javax.management.remote.JMXConnectorFactory}
* or by instantiating {@link RMIConnector}.</p>
*
* <p>This is an abstract class. Concrete subclasses define the
* details of the client connection objects.</p>
*
* @since 1.5
*/
public abstract class RMIServerImpl implements Closeable, RMIServer {
/**
* <p>Constructs a new <code>RMIServerImpl</code>.</p>
*
* @param env the environment containing attributes for the new
* <code>RMIServerImpl</code>. Can be null, which is equivalent
* to an empty Map.
*/
public RMIServerImpl(Map<String,?> env) {
this.env = (env == null) ? Collections.<String,Object>emptyMap() : env;
}
void setRMIConnectorServer(RMIConnectorServer connServer)
throws IOException {
this.connServer = connServer;
}
/**
* <p>Exports this RMI object.</p>
*
* @exception IOException if this RMI object cannot be exported.
*/
protected abstract void export() throws IOException;
/**
* Returns a remotable stub for this server object.
* @return a remotable stub.
* @exception IOException if the stub cannot be obtained - e.g the
* RMIServerImpl has not been exported yet.
**/
public abstract Remote toStub() throws IOException;
/**
* <p>Sets the default <code>ClassLoader</code> for this connector
* server. New client connections will use this classloader.
* Existing client connections are unaffected.</p>
*
* @param cl the new <code>ClassLoader</code> to be used by this
* connector server.
*
* @see #getDefaultClassLoader
*/
public synchronized void setDefaultClassLoader(ClassLoader cl) {
this.cl = cl;
}
/**
* <p>Gets the default <code>ClassLoader</code> used by this connector
* server.</p>
*
* @return the default <code>ClassLoader</code> used by this
* connector server.
*
* @see #setDefaultClassLoader
*/
public synchronized ClassLoader getDefaultClassLoader() {
return cl;
}
/**
* <p>Sets the <code>MBeanServer</code> to which this connector
* server is attached. New client connections will interact
* with this <code>MBeanServer</code>. Existing client connections are
* unaffected.</p>
*
* @param mbs the new <code>MBeanServer</code>. Can be null, but
* new client connections will be refused as long as it is.
*
* @see #getMBeanServer
*/
public synchronized void setMBeanServer(MBeanServer mbs) {
this.mbeanServer = mbs;
}
/**
* <p>The <code>MBeanServer</code> to which this connector server
* is attached. This is the last value passed to {@link
* #setMBeanServer} on this object, or null if that method has
* never been called.</p>
*
* @return the <code>MBeanServer</code> to which this connector
* is attached.
*
* @see #setMBeanServer
*/
public synchronized MBeanServer getMBeanServer() {
return mbeanServer;
}
public String getVersion() {
// Expected format is: "protocol-version implementation-name"
try {
return "1.0 java_runtime_" +
System.getProperty("java.runtime.version");
} catch (SecurityException e) {
return "1.0 ";
}
}
/**
* <p>Creates a new client connection. This method calls {@link
* #makeClient makeClient} and adds the returned client connection
* object to an internal list. When this
* <code>RMIServerImpl</code> is shut down via its {@link
* #close()} method, the {@link RMIConnection#close() close()}
* method of each object remaining in the list is called.</p>
*
* <p>The fact that a client connection object is in this internal
* list does not prevent it from being garbage collected.</p>
*
* @param credentials this object specifies the user-defined
* credentials to be passed in to the server in order to
* authenticate the caller before creating the
* <code>RMIConnection</code>. Can be null.
*
* @return the newly-created <code>RMIConnection</code>. This is
* usually the object created by <code>makeClient</code>, though
* an implementation may choose to wrap that object in another
* object implementing <code>RMIConnection</code>.
*
* @exception IOException if the new client object cannot be
* created or exported.
*
* @exception SecurityException if the given credentials do not allow
* the server to authenticate the user successfully.
*
* @exception IllegalStateException if {@link #getMBeanServer()}
* is null.
*/
public RMIConnection newClient(Object credentials) throws IOException {
return doNewClient(credentials);
}
/**
* This method could be overridden by subclasses defined in this package
* to perform additional operations specific to the underlying transport
* before creating the new client connection.
*/
RMIConnection doNewClient(Object credentials) throws IOException {
final boolean tracing = logger.traceOn();
if (tracing) logger.trace("newClient","making new client");
if (getMBeanServer() == null)
throw new IllegalStateException("Not attached to an MBean server");
Subject subject = null;
JMXAuthenticator authenticator =
(JMXAuthenticator) env.get(JMXConnectorServer.AUTHENTICATOR);
if (authenticator == null) {
/*
* Create the JAAS-based authenticator only if authentication
* has been enabled
*/
if (env.get("jmx.remote.x.password.file") != null ||
env.get("jmx.remote.x.login.config") != null) {
authenticator = new JMXPluggableAuthenticator(env);
}
}
if (authenticator != null) {
if (tracing) logger.trace("newClient","got authenticator: " +
authenticator.getClass().getName());
try {
subject = authenticator.authenticate(credentials);
} catch (SecurityException e) {
logger.trace("newClient", "Authentication failed: " + e);
throw e;
}
}
if (tracing) {
if (subject != null)
logger.trace("newClient","subject is not null");
else logger.trace("newClient","no subject");
}
final String connectionId = makeConnectionId(getProtocol(), subject);
if (tracing)
logger.trace("newClient","making new connection: " + connectionId);
RMIConnection client = makeClient(connectionId, subject);
dropDeadReferences();
WeakReference<RMIConnection> wr = new WeakReference<RMIConnection>(client);
synchronized (clientList) {
clientList.add(wr);
}
connServer.connectionOpened(connectionId, "Connection opened", null);
synchronized (clientList) {
if (!clientList.contains(wr)) {
// can be removed only by a JMXConnectionNotification listener
throw new IOException("The connection is refused.");
}
}
if (tracing)
logger.trace("newClient","new connection done: " + connectionId );
return client;
}
/**
* <p>Creates a new client connection. This method is called by
* the public method {@link #newClient(Object)}.</p>
*
* @param connectionId the ID of the new connection. Every
* connection opened by this connector server will have a
* different ID. The behavior is unspecified if this parameter is
* null.
*
* @param subject the authenticated subject. Can be null.
*
* @return the newly-created <code>RMIConnection</code>.
*
* @exception IOException if the new client object cannot be
* created or exported.
*/
protected abstract RMIConnection makeClient(String connectionId,
Subject subject)
throws IOException;
/**
* <p>Closes a client connection made by {@link #makeClient makeClient}.
*
* @param client a connection previously returned by
* <code>makeClient</code> on which the <code>closeClient</code>
* method has not previously been called. The behavior is
* unspecified if these conditions are violated, including the
* case where <code>client</code> is null.
*
* @exception IOException if the client connection cannot be
* closed.
*/
protected abstract void closeClient(RMIConnection client)
throws IOException;
/**
* <p>Returns the protocol string for this object. The string is
* <code>rmi</code> for RMI/JRMP.
*
* @return the protocol string for this object.
*/
protected abstract String getProtocol();
/**
* <p>Method called when a client connection created by {@link
* #makeClient makeClient} is closed. A subclass that defines
* <code>makeClient</code> must arrange for this method to be
* called when the resultant object's {@link RMIConnection#close()
* close} method is called. This enables it to be removed from
* the <code>RMIServerImpl</code>'s list of connections. It is
* not an error for <code>client</code> not to be in that
* list.</p>
*
* <p>After removing <code>client</code> from the list of
* connections, this method calls {@link #closeClient
* closeClient(client)}.</p>
*
* @param client the client connection that has been closed.
*
* @exception IOException if {@link #closeClient} throws this
* exception.
*
* @exception NullPointerException if <code>client</code> is null.
*/
protected void clientClosed(RMIConnection client) throws IOException {
final boolean debug = logger.debugOn();
if (debug) logger.trace("clientClosed","client="+client);
if (client == null)
throw new NullPointerException("Null client");
synchronized (clientList) {
dropDeadReferences();
for (Iterator<WeakReference<RMIConnection>> it = clientList.iterator();
it.hasNext(); ) {
WeakReference<RMIConnection> wr = it.next();
if (wr.get() == client) {
it.remove();
break;
}
}
/* It is not a bug for this loop not to find the client. In
our close() method, we remove a client from the list before
calling its close() method. */
}
if (debug) logger.trace("clientClosed", "closing client.");
closeClient(client);
if (debug) logger.trace("clientClosed", "sending notif");
connServer.connectionClosed(client.getConnectionId(),
"Client connection closed", null);
if (debug) logger.trace("clientClosed","done");
}
/**
* <p>Closes this connection server. This method first calls the
* {@link #closeServer()} method so that no new client connections
* will be accepted. Then, for each remaining {@link
* RMIConnection} object returned by {@link #makeClient
* makeClient}, its {@link RMIConnection#close() close} method is
* called.</p>
*
* <p>The behavior when this method is called more than once is
* unspecified.</p>
*
* <p>If {@link #closeServer()} throws an
* <code>IOException</code>, the individual connections are
* nevertheless closed, and then the <code>IOException</code> is
* thrown from this method.</p>
*
* <p>If {@link #closeServer()} returns normally but one or more
* of the individual connections throws an
* <code>IOException</code>, then, after closing all the
* connections, one of those <code>IOException</code>s is thrown
* from this method. If more than one connection throws an
* <code>IOException</code>, it is unspecified which one is thrown
* from this method.</p>
*
* @exception IOException if {@link #closeServer()} or one of the
* {@link RMIConnection#close()} calls threw
* <code>IOException</code>.
*/
public synchronized void close() throws IOException {
final boolean tracing = logger.traceOn();
final boolean debug = logger.debugOn();
if (tracing) logger.trace("close","closing");
IOException ioException = null;
try {
if (debug) logger.debug("close","closing Server");
closeServer();
} catch (IOException e) {
if (tracing) logger.trace("close","Failed to close server: " + e);
if (debug) logger.debug("close",e);
ioException = e;
}
if (debug) logger.debug("close","closing Clients");
// Loop to close all clients
while (true) {
synchronized (clientList) {
if (debug) logger.debug("close","droping dead references");
dropDeadReferences();
if (debug) logger.debug("close","client count: "+clientList.size());
if (clientList.size() == 0)
break;
/* Loop until we find a non-null client. Because we called
dropDeadReferences(), this will usually be the first
element of the list, but a garbage collection could have
happened in between. */
for (Iterator<WeakReference<RMIConnection>> it = clientList.iterator();
it.hasNext(); ) {
WeakReference<RMIConnection> wr = it.next();
RMIConnection client = wr.get();
it.remove();
if (client != null) {
try {
client.close();
} catch (IOException e) {
if (tracing)
logger.trace("close","Failed to close client: " + e);
if (debug) logger.debug("close",e);
if (ioException == null)
ioException = e;
}
break;
}
}
}
}
if(notifBuffer != null)
notifBuffer.dispose();
if (ioException != null) {
if (tracing) logger.trace("close","close failed.");
throw ioException;
}
if (tracing) logger.trace("close","closed.");
}
/**
* <p>Called by {@link #close()} to close the connector server.
* After returning from this method, the connector server must
* not accept any new connections.</p>
*
* @exception IOException if the attempt to close the connector
* server failed.
*/
protected abstract void closeServer() throws IOException;
private static synchronized String makeConnectionId(String protocol,
Subject subject) {
connectionIdNumber++;
String clientHost = "";
try {
clientHost = RemoteServer.getClientHost();
/*
* According to the rules specified in the javax.management.remote
* package description, a numeric IPv6 address (detected by the
* presence of otherwise forbidden ":" character) forming a part
* of the connection id must be enclosed in square brackets.
*/
if (clientHost.contains(":")) {
clientHost = "[" + clientHost + "]";
}
} catch (ServerNotActiveException e) {
logger.trace("makeConnectionId", "getClientHost", e);
}
final StringBuilder buf = new StringBuilder();
buf.append(protocol).append(":");
if (clientHost.length() > 0)
buf.append("//").append(clientHost);
buf.append(" ");
if (subject != null) {
Set<Principal> principals = subject.getPrincipals();
String sep = "";
for (Iterator<Principal> it = principals.iterator(); it.hasNext(); ) {
Principal p = it.next();
String name = p.getName().replace(' ', '_').replace(';', ':');
buf.append(sep).append(name);
sep = ";";
}
}
buf.append(" ").append(connectionIdNumber);
if (logger.traceOn())
logger.trace("newConnectionId","connectionId="+buf);
return buf.toString();
}
private void dropDeadReferences() {
synchronized (clientList) {
for (Iterator<WeakReference<RMIConnection>> it = clientList.iterator();
it.hasNext(); ) {
WeakReference<RMIConnection> wr = it.next();
if (wr.get() == null)
it.remove();
}
}
}
synchronized NotificationBuffer getNotifBuffer() {
//Notification buffer is lazily created when the first client connects
if(notifBuffer == null)
notifBuffer =
ArrayNotificationBuffer.getNotificationBuffer(mbeanServer,
env);
return notifBuffer;
}
private static final ClassLogger logger =
new ClassLogger("javax.management.remote.rmi", "RMIServerImpl");
/** List of WeakReference values. Each one references an
RMIConnection created by this object, or null if the
RMIConnection has been garbage-collected. */
private final List<WeakReference<RMIConnection>> clientList =
new ArrayList<WeakReference<RMIConnection>>();
private ClassLoader cl;
private MBeanServer mbeanServer;
private final Map<String, ?> env;
private RMIConnectorServer connServer;
private static int connectionIdNumber;
private NotificationBuffer notifBuffer;
}