/*******************************************************************************
* 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.capsd.plugins;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.InterruptedIOException;
import java.lang.reflect.UndeclaredThrowableException;
import java.net.ConnectException;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.NoRouteToHostException;
import java.net.Socket;
import java.util.Map;
import java.util.StringTokenizer;
import org.apache.regexp.RE;
import org.apache.regexp.RESyntaxException;
import org.opennms.core.utils.InetAddressUtils;
import org.opennms.core.utils.ParameterMap;
import org.opennms.core.utils.ThreadCategory;
import org.opennms.netmgt.capsd.AbstractPlugin;
/**
* <P>
* This class is designed to be used by the capabilities daemon to test for the
* existance of an SMTP server on remote interfaces. The class implements the
* Plugin interface that allows it to be used along with other plugins by the
* daemon.
* </P>
*
* @author <a href="mailto:sowmya@opennms.org">Sowmya</a>
* @author <a href="mailto:weave@oculan.com">Weave</a>
* @author <a href="http://www.opennms.org">OpenNMS</a>
*/
public final class SmtpPlugin extends AbstractPlugin {
/**
* The regular expression test used to determine if the reply is a multi
* line reply. A multi line reply is one that each line, but the last, is in
* the form of "ddd-" where 'ddd' is the result code.
*
*/
private static final RE MULTILINE_RESULT;
/**
* <P>
* The capability name of the plugin.
* </P>
*/
private static final String PROTOCOL_NAME = "SMTP";
/**
* <P>
* The default port on which the host is checked to see if it supports SMTP.
* </P>
*/
private static final int DEFAULT_PORT = 25;
/**
* Default number of retries for SMTP requests.
*/
private final static int DEFAULT_RETRY = 0;
/**
* Default timeout (in milliseconds) for SMTP requests.
*/
private final static int DEFAULT_TIMEOUT = 5000; // in milliseconds
/**
* The name of the local host.
*/
private static final String LOCALHOST_NAME = InetAddressUtils.getLocalHostName();
static {
try {
MULTILINE_RESULT = new RE("^[1-5][0-9]{2}-");
} catch (RESyntaxException re) {
throw new java.lang.reflect.UndeclaredThrowableException(re);
}
}
/**
* <P>
* Test to see if the passed host-port pair is the endpoint for an SMTP
* server. If there is an SMTP server at that destination then a value of
* true is returned from the method. Otherwise a false value is returned to
* the caller.
* </P>
*
* @param host
* The remote host to connect to.
* @param port
* The remote port on the host.
*
* @return True if server supports SMTP on the specified port, false
* otherwise
*/
private boolean isServer(InetAddress host, int port, int retries, int timeout) {
// get a log to send errors
//
ThreadCategory log = ThreadCategory.getInstance(getClass());
boolean isAServer = false;
for (int attempts = 0; attempts <= retries && !isAServer; attempts++) {
Socket socket = null;
try {
socket = new Socket();
socket.connect(new InetSocketAddress(host, port), timeout);
socket.setSoTimeout(timeout);
log.debug("SmtpPlugin: connected to host: " + host + " on port: " + port);
// Allocate a line reader
//
BufferedReader lineRdr = new BufferedReader(new InputStreamReader(socket.getInputStream()));
// Read responses from the server. The initial line should just
// be a banner, but go ahead and check for multiline response.
//
String result = null;
do {
result = lineRdr.readLine();
} while (result != null && result.length() > 0 && MULTILINE_RESULT.match(result));
if (result == null || result.length() == 0) {
log.info("Received truncated response from SMTP server " + InetAddressUtils.str(host));
continue;
}
// Tokenize the last line result
//
StringTokenizer t = new StringTokenizer(result);
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());
// Response from HELO command may be a multi-line response
// (but
// most likely will be single-line)..
// We are expecting to get a response with an integer return
// code in the first token. We can't ge sure that the first
// response will give us what we want. Consider the
// following
// reponse for example:
//
// 250-First line
// 250-Second line
// 250 Requested mail action okay, completed
//
// In this case the final line of the response contains the
// return
// code we are looking for.
do {
result = lineRdr.readLine();
} while (result != null && result.length() > 0 && MULTILINE_RESULT.match(result));
if (result == null || result.length() == 0) {
log.info("Received truncated response from SMTP server " + InetAddressUtils.str(host));
continue;
}
t = new StringTokenizer(result);
rc = Integer.parseInt(t.nextToken());
if (rc == 250) {
//
// Send the QUIT command
//
cmd = "QUIT\r\n";
socket.getOutputStream().write(cmd.getBytes());
// Response from QUIT command may be a multi-line
// response.
// We are expecting to get a response with an integer
// return
// code in the first token. We can't ge sure that the
// first
// response will give us what we want. Consider the
// following
// reponse for example:
//
// 221-First line
// 221-Second line
// 221 <domain> Service closing transmission channel.
//
// In this case the final line of the response contains
// the return
// code we are looking for.
do {
result = lineRdr.readLine();
} while (result != null && result.length() > 0 && MULTILINE_RESULT.match(result));
if (result == null || result.length() == 0) {
log.info("Received truncated response from SMTP server " + InetAddressUtils.str(host));
continue;
}
t = new StringTokenizer(result);
rc = Integer.parseInt(t.nextToken());
if (rc == 221)
isAServer = true;
}
}
} catch (NumberFormatException e) {
log.info("SmtpPlugin: received invalid result code from server " + InetAddressUtils.str(host), e);
isAServer = false;
} catch (ConnectException cE) {
// Connection refused!! Continue to retry.
//
log.debug("SmtpPlugin: connection refused to " + InetAddressUtils.str(host) + ":" + port);
isAServer = false;
} catch (NoRouteToHostException e) {
// No route to host!! No need to perform retries.
e.fillInStackTrace();
log.info("SmtpPlugin: Unable to test host " + InetAddressUtils.str(host) + ", no route available", e);
isAServer = false;
throw new UndeclaredThrowableException(e);
} catch (InterruptedIOException e) {
log.debug("SmtpPlugin: did not connect to host within timeout: " + timeout + " attempt: " + attempts);
isAServer = false;
} catch (IOException e) {
log.info("SmtpPlugin: Error communicating with host " + InetAddressUtils.str(host), e);
isAServer = false;
} catch (Throwable t) {
log.warn("SmtpPlugin: Undeclared throwable exception caught contacting host " + InetAddressUtils.str(host), t);
isAServer = false;
} finally {
try {
if (socket != null)
socket.close();
} catch (IOException e) {
}
}
}
//
// return the success/failure of this
// attempt to contact an SMTP server.
//
return isAServer;
}
/**
* Returns the name of the protocol that this plugin checks on the target
* system for support.
*
* @return The protocol name for this plugin.
*/
public String getProtocolName() {
return PROTOCOL_NAME;
}
/**
* {@inheritDoc}
*
* Returns true if the protocol defined by this plugin is supported. If the
* protocol is not supported then a false value is returned to the caller.
*/
public boolean isProtocolSupported(InetAddress address) {
return isServer(address, DEFAULT_PORT, DEFAULT_RETRY, DEFAULT_TIMEOUT);
}
/**
* {@inheritDoc}
*
* Returns true if the protocol defined by this plugin is supported. If the
* protocol is not supported then a false value is returned to the caller.
* The qualifier map passed to the method is used by the plugin to return
* additional information by key-name. These key-value pairs can be added to
* service events if needed.
*/
public boolean isProtocolSupported(InetAddress address, Map<String, Object> qualifiers) {
int retries = DEFAULT_RETRY;
int timeout = DEFAULT_TIMEOUT;
int port = DEFAULT_PORT;
if (qualifiers != null) {
retries = ParameterMap.getKeyedInteger(qualifiers, "retry", DEFAULT_RETRY);
timeout = ParameterMap.getKeyedInteger(qualifiers, "timeout", DEFAULT_TIMEOUT);
port = ParameterMap.getKeyedInteger(qualifiers, "port", DEFAULT_PORT);
}
boolean result = isServer(address, port, retries, timeout);
if (result && qualifiers != null && !qualifiers.containsKey("port"))
qualifiers.put("port", port);
return result;
}
}