SmtpMonitor.java

//
// This file is part of the OpenNMS(R) Application.
//
// OpenNMS(R) is Copyright (C) 2002-2003 The OpenNMS Group, Inc. All rights reserved.
// OpenNMS(R) is a derivative work, containing both original code, included code and modified
// code that was published under the GNU General Public License. Copyrights for modified
// and included code are below.
//
// OpenNMS(R) is a registered trademark of The OpenNMS Group, Inc.
//
// Modifications:
//
// 2004 May 05: Switch from SocketChannel to Socket with connection timeout.
// 2003 Jul 21: Explicitly closed socket.
// 2003 Jul 18: Enabled retries for monitors.
// 2003 Jun 11: Added a "catch" for RRD update errors. Bug #748.
// 2003 Jan 31: Added the ability to imbed RRA information in poller packages.
// 2003 Jan 31: Cleaned up some unused imports.
// 2003 Jan 29: Added response times to certain monitors.
// 2002 Nov 14: Used non-blocking I/O socket channel classes.
//
// Original code base Copyright (C) 1999-2001 Oculan Corp. All rights reserved.
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program 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 for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
//
// For more information contact:
//      OpenNMS Licensing <license@opennms.org>
//      http://www.opennms.org/
//      http://www.opennms.com/
//
// Tab Size = 8
//

package org.infosec.ismp.poller.monitor;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.InterruptedIOException;
import java.net.ConnectException;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.NoRouteToHostException;
import java.net.Socket;
import java.net.UnknownHostException;
import java.util.Map;
import java.util.StringTokenizer;
import java.util.regex.Pattern;
import java.util.regex.PatternSyntaxException;

import org.apache.log4j.Level;
import org.infosec.ismp.model.poller.MonitoredService;
import org.infosec.ismp.model.poller.NetworkInterface;
import org.infosec.ismp.model.poller.NetworkInterfaceNotSupportedException;
import org.infosec.ismp.model.poller.PollStatus;
import org.infosec.ismp.model.poller.monitors.IPv4Monitor;
import org.infosec.ismp.util.ParameterMap;
import org.infosec.ismp.util.ThreadCategory;
import org.infosec.ismp.util.TimeoutTracker;

//import com.sun.org.apache.regexp.internal.RE;
//import com.sun.org.apache.regexp.internal.RESyntaxException;

/**
 * <P>
 * This class is designed to be used by the service poller framework to test the
 * availability of the SMTP service on remote interfaces. The class implements
 * the ServiceMonitor interface that allows it to be used along with other
 * plug-ins by the service poller framework.
 * </P>
 * 
 * @author <A HREF="mailto:tarus@opennms.org">Tarus Balog </A>
 * @author <A HREF="http://www.opennms.org/">OpenNMS </A>
 * 
 */

final public class SmtpMonitor extends IPv4Monitor {

    /**
     * Default SMTP port.
     */
    private static final int DEFAULT_PORT = 25;

    /**
     * Default retries.
     */
    private static final int DEFAULT_RETRY = 0;

    /**
     * Default timeout. Specifies how long (in milliseconds) to block waiting
     * for data from the monitored interface.
     */
    private static final int DEFAULT_TIMEOUT = 3000;

    /**
     * The name of the local host.
     */
    private static String LOCALHOST_NAME;

    /**
     * Used to check for a multiline response. A multline response begins with
     * the same 3 digit response code, but has a hypen after the last number
     * instead of a space.
     */
    private static Pattern MULTILINE = null;

    /**
     * Used to check for the end of a multiline response. The end of a multiline
     * response is the same 3 digit response code followed by a space
     */
    private Pattern ENDMULTILINE = null;

    // Init the local host and MULTILINE
    //
    static {
        try {
            LOCALHOST_NAME = InetAddress.getLocalHost().getHostName();
        } catch (UnknownHostException uhE) {
            ThreadCategory.getInstance(SmtpMonitor.class).error("Failed to resolve localhost name, using localhost");
            LOCALHOST_NAME = "localhost";
        }

        try {
            MULTILINE = Pattern.compile("^[0-9]{3}-");
        } catch (Exception ex) {
            throw new java.lang.reflect.UndeclaredThrowableException(ex);
        }
    }

    /**
     * <P>
     * Poll the specified address for SMTP service availability.
     * </P>
     * 
     * <P>
     * During the poll an attempt is made to connect on the specified port (by
     * default TCP port 25). If the connection request is successful, the banner
     * line generated by the interface is parsed and if the extracted return
     * code indicates that we are talking to an SMTP server we continue. Next,
     * an SMTP 'HELO' command is sent to the interface. Again the response is
     * parsed and a return code extracted and verified. Finally, an SMTP 'QUIT'
     * command is sent. Provided that the interface's response is valid we set
     * the service status to SERVICE_AVAILABLE and return.
     * </P>
     * @param parameters
     *            The package parameters (timeout, retry, etc...) to be used for
     *            this poll.
     * @param iface
     *            The network interface to test the service on.
     * @return The availibility of the interface and if a transition event
     *         should be supressed.
     * 
     */
    public PollStatus poll(MonitoredService svc, Map<String, Object> parameters) {
        NetworkInterface iface = svc.getNetInterface();

        // Get interface address from NetworkInterface
        //
        if (iface.getType() != NetworkInterface.TYPE_IPV4) {
            throw new NetworkInterfaceNotSupportedException("Unsupported interface type, only TYPE_IPV4 currently supported");
        }
        
        TimeoutTracker tracker = new TimeoutTracker(parameters, DEFAULT_RETRY, DEFAULT_TIMEOUT);

        int port = ParameterMap.getKeyedInteger(parameters, "port", DEFAULT_PORT);

        // Get interface address from NetworkInterface
        //
        InetAddress ipv4Addr = (InetAddress) iface.getAddress();

        if (log().isDebugEnabled())
            log().debug("poll: address = " + ipv4Addr.getHostAddress() + ", port = " + port + ", " + tracker);

        PollStatus serviceStatus = PollStatus.unavailable();

        for (tracker.reset(); tracker.shouldRetry() && !serviceStatus.isAvailable(); tracker.nextAttempt()) {
            Socket socket = null;
            try {
                // create a connected socket
                //
                tracker.startAttempt();

                socket = new Socket();
                socket.connect(new InetSocketAddress(ipv4Addr, port), tracker.getConnectionTimeout());
                socket.setSoTimeout(tracker.getSoTimeout());

                log().debug("SmtpMonitor: connected to host: " + ipv4Addr + " on port: " + port);

                // We're connected, so upgrade status to unresponsive
                serviceStatus = PollStatus.unresponsive();

                BufferedReader rdr = new BufferedReader(new InputStreamReader(socket.getInputStream()));

                //
                // Tokenize the Banner Line, and check the first
                // line for a valid return.
                //
                String banner = rdr.readLine();

                if (banner == null)
                    continue;
                
                if (MULTILINE.matcher(banner).matches()) {
                    // Ok we have a multi-line response...first three
                    // chars of the response line are the return code.
                    // The last line of the response will start with
                    // return code followed by a space.
                    String multiLineRC = new String(banner.getBytes(), 0, 3) + " ";

                    // Create new regExp to look for last line
                    // of this mutli line response
                    try {
                        ENDMULTILINE = Pattern.compile(multiLineRC);
                    } catch (PatternSyntaxException ex) {
                        throw new java.lang.reflect.UndeclaredThrowableException(ex);
                    }

                    // read until we hit the last line of the multi-line
                    // response
                    do {
                        banner = rdr.readLine();
                    } while (banner != null && !ENDMULTILINE.matcher(banner).matches());
                    if (banner == null)
                        continue;
                }

                if (log().isDebugEnabled())
                    log().debug("poll: banner = " + banner);

                StringTokenizer t = new StringTokenizer(banner);
                int rc = Integer.parseInt(t.nextToken());
                if (rc == 220) {
                    //
                    // Send the HELO command
                    //
                    String cmd = "HELO " + LOCALHOST_NAME + "\r\n";
                    socket.getOutputStream().write(cmd.getBytes());

                    //
                    // get the returned string, tokenize, and
                    // verify the correct output.
                    //
                    String response = rdr.readLine();
                    double responseTime = tracker.elapsedTimeInMillis();

                    if (response == null)
                        continue;
                    if (MULTILINE.matcher(response).matches()) {
                        // Ok we have a multi-line response...first three
                        // chars of the response line are the return code.
                        // The last line of the response will start with
                        // return code followed by a space.
                        String multiLineRC = new String(response.getBytes(), 0, 3) + " ";

                        // Create new regExp to look for last line
                        // of this mutli line response
                        try {
                            ENDMULTILINE = Pattern.compile(multiLineRC);
                        } catch (PatternSyntaxException ex) {
                            throw new java.lang.reflect.UndeclaredThrowableException(ex);
                        }

                        // read until we hit the last line of the multi-line
                        // response
                        do {
                            response = rdr.readLine();
                        } while (response != null && !ENDMULTILINE.matcher(response).matches());
                        if (response == null)
                            continue;
                    }

                    t = new StringTokenizer(response);
                    rc = Integer.parseInt(t.nextToken());
                    if (rc == 250) {
                        cmd = "QUIT\r\n";
                        socket.getOutputStream().write(cmd.getBytes());

                        //
                        // get the returned string, tokenize, and
                        // verify the correct output.
                        //
                        response = rdr.readLine();
                        if (response == null)
                            continue;
                        if (MULTILINE.matcher(response).matches()) {
                            // Ok we have a multi-line response...first three
                            // chars of the response line are the return code.
                            // The last line of the response will start with
                            // return code followed by a space.
                            String multiLineRC = new String(response.getBytes(), 0, 3) + " ";

                            // Create new regExp to look for last line
                            // of this mutli line response
                            try {
                                ENDMULTILINE = Pattern.compile(multiLineRC);
                            } catch (PatternSyntaxException ex) {
                                throw new java.lang.reflect.UndeclaredThrowableException(ex);
                            }

                            // read until we hit the last line of the multi-line
                            // response
                            do {
                                response = rdr.readLine();
                            } while (response != null && !ENDMULTILINE.matcher(response).matches());
                            if (response == null)
                                continue;
                        }

                        t = new StringTokenizer(response);
                        rc = Integer.parseInt(t.nextToken());

                        if (rc == 221) {
                            serviceStatus = PollStatus.available(responseTime);
                        }
                    }
                }

                // If we get this far and the status has not been set
                // to available, then something didn't verify during
                // the banner checking or HELO/QUIT comand process.
                if (!serviceStatus.isAvailable()) {
                    serviceStatus = PollStatus.unavailable();
                }
            } catch (NumberFormatException e) {
            	serviceStatus = logDown(Level.DEBUG, "NumberFormatException while polling address " + ipv4Addr.getHostAddress(), e);
            } catch (NoRouteToHostException e) {
            	serviceStatus = logDown(Level.DEBUG, "No route to host exception for address " + ipv4Addr.getHostAddress(), e);
                break; // Break out of for(;;)
            } catch (InterruptedIOException e) {
            	serviceStatus = logDown(Level.DEBUG, "Did not receive expected response within timeout " + tracker);
            } catch (ConnectException e) {
            	serviceStatus = logDown(Level.DEBUG, "Unable to connect to address " + ipv4Addr.getHostAddress(), e);
            } catch (IOException e) {
            	serviceStatus = logDown(Level.DEBUG, "IOException while polling address " + ipv4Addr.getHostAddress(), e);
            } finally {
                try {
                    // Close the socket
                    if (socket != null)
                        socket.close();
                } catch (IOException e) {
                    e.fillInStackTrace();
                    if (log().isDebugEnabled())
                        log().debug("poll: Error closing socket.", e);
                }
            }
        }

        //
        // return the status of the service
        //
        return serviceStatus;
    }

}