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 * Copyright (c) 2002, 2016, 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

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package javax.management.remote.rmi;

import java.io.IOException;

import java.io.ObjectInputFilter;

import java.rmi.NoSuchObjectException;

import java.rmi.Remote;

import java.rmi.RemoteException;

import java.rmi.server.RMIClientSocketFactory;

import java.rmi.server.RMIServerSocketFactory;

import java.rmi.server.UnicastRemoteObject;

import java.rmi.server.RemoteObject;

import java.util.Map;

import java.util.Collections;

import javax.security.auth.Subject;

import com.sun.jmx.remote.internal.rmi.RMIExporter;

import com.sun.jmx.remote.util.EnvHelp;

import java.util.Arrays;

import java.util.Set;

import java.util.stream.Collectors;

import sun.reflect.misc.ReflectUtil;

import sun.rmi.server.UnicastServerRef;

import sun.rmi.server.UnicastServerRef2;

import sun.rmi.transport.LiveRef;

/**

 * <p>An {@link RMIServer} object that is exported through JRMP and that

 * creates client connections as RMI objects exported through JRMP.

 * User code does not usually reference this class directly.</p>

 *

 * @see RMIServerImpl

 *

 * @since 1.5

 */

public class RMIJRMPServerImpl extends RMIServerImpl {

    /**

     * <p>Creates a new {@link RMIServer} object that will be exported

     * on the given port using the given socket factories.</p>

     *

     * @param port the port on which this object and the {@link

     * RMIConnectionImpl} objects it creates will be exported.  Can be

     * zero, to indicate any available port.

     *

     * @param csf the client socket factory for the created RMI

     * objects.  Can be null.

     *

     * @param ssf the server socket factory for the created RMI

     * objects.  Can be null.

     *

     * @param env the environment map.  Can be null.

     *

     * @exception IOException if the {@link RMIServer} object

     * cannot be created.

     *

     * @exception IllegalArgumentException if <code>port</code> is

     * negative.

     */

    public RMIJRMPServerImpl(int port,

                             RMIClientSocketFactory csf,

                             RMIServerSocketFactory ssf,

                             Map<String,?> env)

            throws IOException {

        super(env);

        if (port < 0)

            throw new IllegalArgumentException("Negative port: " + port);

        this.port = port;

        this.csf = csf;

        this.ssf = ssf;

        this.env = (env == null) ? Collections.<String, Object>emptyMap() : env;

        // This attribute was represented by RMIConnectorServer.CREDENTIALS_TYPES.

        // This attribute is superceded by

        // RMIConnectorServer.CREDENTIALS_FILTER_PATTERN.

        // Retaining this for backward compatibility.

        String[] credentialsTypes

                = (String[]) this.env.get("jmx.remote.rmi.server.credential.types");

        String credentialsFilter

                = (String) this.env.get(RMIConnectorServer.CREDENTIALS_FILTER_PATTERN);

        // It is impossible for both attributes to be specified

        if(credentialsTypes != null && credentialsFilter != null)

            throw new IllegalArgumentException("Cannot specify both \""

                    + "jmx.remote.rmi.server.credential.types" + "\" and \""

           + RMIConnectorServer.CREDENTIALS_FILTER_PATTERN + "\"");

        else if(credentialsFilter != null){

            cFilter = ObjectInputFilter.Config.createFilter(credentialsFilter);

            allowedTypes = null;

        }

        else if (credentialsTypes != null) {

            allowedTypes = Arrays.stream(credentialsTypes).filter(

                    s -> s!= null).collect(Collectors.toSet());

            allowedTypes.stream().forEach(ReflectUtil::checkPackageAccess);

            cFilter = this::newClientCheckInput;

        } else {

            allowedTypes = null;

            cFilter = null;

        }

        String userJmxFilter =

                (String) this.env.get(RMIConnectorServer.SERIAL_FILTER_PATTERN);

        if(userJmxFilter != null && !userJmxFilter.isEmpty())

            jmxRmiFilter = ObjectInputFilter.Config.createFilter(userJmxFilter);

        else

            jmxRmiFilter = null;

    }

    protected void export() throws IOException {

        export(this, cFilter);

    }

    private void export(Remote obj, ObjectInputFilter typeFilter) throws RemoteException {

        final RMIExporter exporter =

            (RMIExporter) env.get(RMIExporter.EXPORTER_ATTRIBUTE);

        final boolean daemon = EnvHelp.isServerDaemon(env);

        if (daemon && exporter != null) {

            throw new IllegalArgumentException("If "+EnvHelp.JMX_SERVER_DAEMON+

                    " is specified as true, "+RMIExporter.EXPORTER_ATTRIBUTE+

                    " cannot be used to specify an exporter!");

        }

        if (exporter != null) {

            exporter.exportObject(obj, port, csf, ssf, typeFilter);

        } else {

            if (csf == null && ssf == null) {

                new UnicastServerRef(new LiveRef(port), typeFilter).exportObject(obj, null, daemon);

            } else {

                new UnicastServerRef2(port, csf, ssf, typeFilter).exportObject(obj, null, daemon);

            }

        }

    }

    private void unexport(Remote obj, boolean force)

            throws NoSuchObjectException {

        RMIExporter exporter =

            (RMIExporter) env.get(RMIExporter.EXPORTER_ATTRIBUTE);

        if (exporter == null)

            UnicastRemoteObject.unexportObject(obj, force);

        else

            exporter.unexportObject(obj, force);

    }

    protected String getProtocol() {

        return "rmi";

    }

    /**

     * <p>Returns a serializable stub for this {@link RMIServer} object.</p>

     *

     * @return a serializable stub.

     *

     * @exception IOException if the stub cannot be obtained - e.g the

     *            RMIJRMPServerImpl has not been exported yet.

     */

    public Remote toStub() throws IOException {

        return RemoteObject.toStub(this);

    }

    /**

     * <p>Creates a new client connection as an RMI object exported

     * through JRMP. The port and socket factories for the new

     * {@link RMIConnection} object are the ones supplied

     * to the <code>RMIJRMPServerImpl</code> constructor.</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 {@link RMIConnection}

     * object cannot be created or exported.

     */

    protected RMIConnection makeClient(String connectionId, Subject subject)

            throws IOException {

        if (connectionId == null)

            throw new NullPointerException("Null connectionId");

        RMIConnection client =

            new RMIConnectionImpl(this, connectionId, getDefaultClassLoader(),

                                  subject, env);

        export(client, jmxRmiFilter);

        return client;

    }

    protected void closeClient(RMIConnection client) throws IOException {

        unexport(client, true);

    }

    /**

     * <p>Called by {@link #close()} to close the connector server by

     * unexporting this object.  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 void closeServer() throws IOException {

        unexport(this, true);

    }

    /**

     * Check that a type in the remote invocation of {@link RMIServerImpl#newClient}

     * is one of the {@code allowedTypes}.

     *

     * @param clazz       the class; may be null

     * @param size        the size for arrays, otherwise is 0

     * @param nObjectRefs the current number of object references

     * @param depth       the current depth

     * @param streamBytes the current number of bytes consumed

     * @return {@code ObjectInputFilter.Status.ALLOWED} if the class is allowed,

     *          otherwise {@code ObjectInputFilter.Status.REJECTED}

     */

    ObjectInputFilter.Status newClientCheckInput(ObjectInputFilter.FilterInfo filterInfo) {

        ObjectInputFilter.Status status = ObjectInputFilter.Status.UNDECIDED;

        if (allowedTypes != null && filterInfo.serialClass() != null) {

            // If enabled, check type

            String type = filterInfo.serialClass().getName();

            if (allowedTypes.contains(type))

                status = ObjectInputFilter.Status.ALLOWED;

            else

                status = ObjectInputFilter.Status.REJECTED;

        }

        return status;

    }

    private final int port;

    private final RMIClientSocketFactory csf;

    private final RMIServerSocketFactory ssf;

    private final Map<String, ?> env;

    private final Set<String> allowedTypes;

    private final ObjectInputFilter jmxRmiFilter;

    private final ObjectInputFilter cFilter;

}