/*******************************************************************************
* Copyright (c) 2007, 2014 Massimiliano Ziccardi
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*******************************************************************************/
package it.jnrpe.plugin;
import it.jnrpe.ICommandLine;
import it.jnrpe.Status;
import it.jnrpe.plugin.utils.SshUtils;
import it.jnrpe.plugin.utils.Utils;
import it.jnrpe.plugins.Metric;
import it.jnrpe.plugins.MetricGatheringException;
import it.jnrpe.plugins.PluginBase;
import it.jnrpe.plugins.annotations.Option;
import it.jnrpe.plugins.annotations.Plugin;
import it.jnrpe.plugins.annotations.PluginOptions;
import it.jnrpe.utils.BadThresholdException;
import it.jnrpe.utils.thresholds.ThresholdsEvaluatorBuilder;
import java.io.IOException;
import java.io.InputStream;
import java.math.BigDecimal;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import com.jcraft.jsch.Channel;
import com.jcraft.jsch.ChannelExec;
import com.jcraft.jsch.JSchException;
import com.jcraft.jsch.Session;
/**
* This plugins executes remote commands through ssh and returns the command's
* output (if successul).
*
* @author Frederico Campos
*
*/
@Plugin(name = "CHECK_BY_SSH", description = "Use ssh to execute commands on a remote host.\n" + "EXAMPLES:\n"
+ "The example will be based upon the following command definition (ini file)\n\n"
+ "check_by_ssh : CHECK_BY_SSH --hostname $ARG1$ --port $ARG2$ --password $ARG3$ -C $ARG4$\n"
+ "check_nrpe -H myjnrpeserver -c check_ssh -a myhostname 22 password uptime")
@PluginOptions({
@Option(shortName = "h", longName = "hostname", description = "IP or hostname", required = true, hasArgs = true, argName = "hostname", optionalArgs = false, option = "hostname"),
@Option(shortName = "p", longName = "port", description = "Port number. Default is 22.", required = false, hasArgs = true, argName = "port", optionalArgs = false, option = "port"),
@Option(shortName = "u", longName = "username", description = "Username.", required = true, hasArgs = true, argName = "username", optionalArgs = false, option = "username"),
@Option(shortName = "P", longName = "password", description = "Password.", required = true, hasArgs = true, argName = "hostname", optionalArgs = false, option = "password"),
@Option(shortName = "t", longName = "timeout", description = "Seconds before connection times out (default: 10)", required = false, hasArgs = true, argName = "timeout", optionalArgs = false, option = "timeout"),
@Option(shortName = "w", longName = "warning", description = "Response time to result in warning status (seconds)", required = false, hasArgs = true, argName = "warning", optionalArgs = false, option = "warning"),
@Option(shortName = "c", longName = "critical", description = "Response time to result in critical status (seconds)", required = false, hasArgs = true, argName = "critical", optionalArgs = false, option = "critical"),
@Option(shortName = "C", longName = "command", description = "command to execute on the remote machine", required = true, hasArgs = true, argName = "command", optionalArgs = false, option = "command") })
public class CheckBySsh extends PluginBase {
/**
* Possible unix return codes
*/
/**
* command not found
*/
private static final int ERR_CMD_NOT_FOUND = 127;
/**
* no permision
*/
private static final int ERR_NO_PERMISSION = 126;
@Override
protected String getPluginName() {
return "CHECK_BY_SSH";
}
@Override
public final void configureThresholdEvaluatorBuilder(final ThresholdsEvaluatorBuilder thrb, final ICommandLine cl) throws BadThresholdException {
thrb.withLegacyThreshold("session", "1", null, "0");
thrb.withLegacyThreshold("response", null, cl.getOptionValue("warning"), cl.getOptionValue("critical"));
thrb.withLegacyThreshold("result", "1", null, "0");
}
@Override
public final Collection<Metric> gatherMetrics(final ICommandLine cl) throws MetricGatheringException {
List<Metric> metrics = new ArrayList<Metric>();
Session session = null;
Channel channel = null;
String command = cl.getOptionValue("command");
InputStream in = null;
boolean hasSession = false;
long then = System.currentTimeMillis();
try {
session = SshUtils.getSession(cl);
channel = session.openChannel("exec");
hasSession = true;
metrics.add(new Metric("session", "", new BigDecimal(1), null, null));
} catch (Exception e) {
// metrics.add(new Metric("session",
// "SSH not started, permission denied. " + e.getMessage(),
// new BigDecimal(0), null, null));
LOG.debug(getContext(), e.getMessage(), e);
throw new MetricGatheringException("SSH not started, permission denied.", Status.UNKNOWN, e);
}
try {
if (hasSession) {
((ChannelExec) channel).setCommand(command);
channel.setInputStream(null);
((ChannelExec) channel).setErrStream(System.err);
in = channel.getInputStream();
} else {
return metrics;
}
} catch (IOException e1) {
// e1.printStackTrace();
throw new MetricGatheringException(e1.getMessage(), Status.UNKNOWN, e1);
}
try {
channel.connect();
metrics.add(new Metric("connected", "", new BigDecimal(1), null, null));
} catch (JSchException e2) {
// e2.printStackTrace();
throw new MetricGatheringException(e2.getMessage(), Status.UNKNOWN, e2);
}
StringBuilder sb = new StringBuilder();
byte[] tmp = new byte[1024];
int exitStatus = 0;
while (true) {
try {
while (in.available() > 0) {
int i = in.read(tmp, 0, 1024);
if (i < 0)
break;
sb.append(new String(tmp, 0, i, "UTF-8"));
}
} catch (IOException e1) {
throw new MetricGatheringException(e1.getMessage(), Status.UNKNOWN, e1);
}
if (channel.isClosed()) {
exitStatus = channel.getExitStatus();
break;
}
try {
Thread.sleep(1000);
} catch (Exception e) {
LOG.error(getContext(), "gatherMetrics - " + e.getMessage(), e);
}
}
if (channel != null) {
channel.disconnect();
}
session.disconnect();
long response = (System.currentTimeMillis() - then) / 1000;
metrics.add(new Metric("response", "", new BigDecimal(response), null, null));
// sb.append("\nexit-status: " + channel.getExitStatus());
String msg = "";
switch (channel.getExitStatus()) {
case ERR_CMD_NOT_FOUND:
msg = "Command not found.";
break;
case ERR_NO_PERMISSION:
msg = "Not enough permission to execute command.";
break;
default:
break;
}
metrics.add(new Metric("result", msg + " " + sb.toString(), new BigDecimal(Utils.getIntValue(exitStatus == 0)), null, null));
return metrics;
}
}