/*******************************************************************************
* This file is part of OpenNMS(R).
*
* Copyright (C) 2006-2011 The OpenNMS Group, Inc.
* OpenNMS(R) is Copyright (C) 1999-2011 The OpenNMS Group, Inc.
*
* OpenNMS(R) is a registered trademark of The OpenNMS Group, Inc.
*
* OpenNMS(R) 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 3 of the License,
* or (at your option) any later version.
*
* OpenNMS(R) 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 OpenNMS(R). If not, see:
* http://www.gnu.org/licenses/
*
* For more information contact:
* OpenNMS(R) Licensing <license@opennms.org>
* http://www.opennms.org/
* http://www.opennms.com/
*******************************************************************************/
package org.opennms.netmgt.poller.monitors;
import java.net.InetAddress;
import java.util.Map;
import org.apache.regexp.RE;
import org.apache.regexp.RESyntaxException;
import org.opennms.core.utils.LogUtils;
import org.opennms.core.utils.ParameterMap;
import org.opennms.core.utils.TimeoutTracker;
import org.opennms.netmgt.model.PollStatus;
import org.opennms.netmgt.poller.Distributable;
import org.opennms.netmgt.poller.MonitoredService;
import org.opennms.netmgt.poller.NetworkInterface;
import org.opennms.netmgt.poller.NetworkInterfaceNotSupportedException;
import org.opennms.netmgt.protocols.InsufficientParametersException;
import org.opennms.netmgt.protocols.ssh.Ssh;
/**
* This class is designed to be used by the service poller framework to test the
* availability of SSH remote interfaces. The class
* implements the ServiceMonitor interface that allows it to be used along with
* other plug-ins by the service poller framework.
*
* @author <a href="mailto:ranger@opennms.org">Benjamin Reed</a>
* @author <a href="http://www.opennms.org/">OpenNMS</a>
* @author <a href="mailto:ranger@opennms.org">Benjamin Reed</a>
* @author <a href="http://www.opennms.org/">OpenNMS</a>
* @version $Id: $
*/
@Distributable
final public class SshMonitor extends AbstractServiceMonitor {
private static final int DEFAULT_RETRY = 0;
/** Constant <code>DEFAULT_TIMEOUT=3000</code> */
public static final int DEFAULT_TIMEOUT = 3000;
/** Constant <code>DEFAULT_PORT=22</code> */
public static final int DEFAULT_PORT = 22;
/**
* {@inheritDoc}
*
* Poll an {@link InetAddress} for SSH availability.
*
* During the poll an attempt is made to connect on the specified port. If
* the connection request is successful, the banner line generated by the
* interface is parsed and if the banner text indicates that we are talking
* to Provided that the interface's response is valid we mark the poll status
* as available and return.
*/
public PollStatus poll(InetAddress address, Map<String,Object> parameters) {
TimeoutTracker tracker = new TimeoutTracker(parameters, DEFAULT_RETRY, DEFAULT_TIMEOUT);
int port = ParameterMap.getKeyedInteger(parameters, "port", DEFAULT_PORT);
String banner = ParameterMap.getKeyedString(parameters, "banner", null);
String match = ParameterMap.getKeyedString(parameters, "match", null);
String clientBanner = ParameterMap.getKeyedString(parameters, "client-banner", Ssh.DEFAULT_CLIENT_BANNER);
PollStatus ps = PollStatus.unavailable();
Ssh ssh = new Ssh(address, port, tracker.getConnectionTimeout());
ssh.setClientBanner(clientBanner);
RE regex = null;
try {
if (match == null && (banner == null || banner.equals("*"))) {
regex = null;
} else if (match != null) {
regex = new RE(match);
} else if (banner != null) {
regex = new RE(banner);
}
} catch (final RESyntaxException e) {
final String matchString = match == null? banner : match;
LogUtils.infof(this, "Invalid regular expression for SSH banner match /%s/: %s", matchString, e.getMessage());
LogUtils.debugf(this, e, "Invalid Regular expression for SSH banner match /%s/", matchString);
}
for (tracker.reset(); tracker.shouldRetry() && !ps.isAvailable(); tracker.nextAttempt()) {
try {
ps = ssh.poll(tracker);
} catch (final InsufficientParametersException e) {
LogUtils.errorf(this, e, "An error occurred polling host '%s'", address);
break;
}
if (!ps.isAvailable()) {
// not able to connect, retry
continue;
}
// If banner matching string is null or wildcard ("*") then we
// only need to test connectivity and we've got that!
if (regex == null) {
return ps;
} else {
String response = ssh.getServerBanner();
if (response == null) {
return PollStatus.unavailable("server closed connection before banner was received.");
}
if (regex.match(response)) {
LogUtils.debugf(this, "isServer: matching response=%s", response);
return ps;
} else {
// Got a response but it didn't match... no need to attempt
// retries
LogUtils.debugf(this, "isServer: NON-matching response=%s", response);
return PollStatus.unavailable("server responded, but banner did not match '" + banner + "'");
}
}
}
return ps;
}
/**
* {@inheritDoc}
*
* Poll the specified address for service availability.
* @see #poll(InetAddress, Map)
*/
public PollStatus poll(MonitoredService svc, Map<String, Object> parameters) {
NetworkInterface<InetAddress> iface = svc.getNetInterface();
if (iface.getType() != NetworkInterface.TYPE_INET)
throw new NetworkInterfaceNotSupportedException("Unsupported interface type, only TYPE_INET currently supported");
InetAddress address = (InetAddress) iface.getAddress();
return poll(address, parameters);
}
}