/*
* This software copyright by various authors including the RPTools.net
* development team, and licensed under the LGPL Version 3 or, at your
* option, any later version.
*
* Portions of this software were originally covered under the Apache
* Software License, Version 1.1 or Version 2.0.
*
* See the file LICENSE elsewhere in this distribution for license details.
*/
package net.sbbi.upnp;
import java.io.IOException;
import java.net.DatagramPacket;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.SocketTimeoutException;
import java.net.URL;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import org.apache.log4j.Logger;
/**
* SSDP messages listener Thread, notify registered objects implementing the interface DiscoveryEventHandler</br> when a
* device joins the networks or leaves it.<br/>
* The listener thread is set to only accept matching device description and broadcast message sender IP to avoid a
* security flaw with the protocol. If you are not happy with such behaviour you can set the net.sbbi.upnp.ddos.matchip
* system property to false to avoid this check.
*
* @author <a href="mailto:superbonbon@sbbi.net">SuperBonBon</a>
* @version 1.0
*/
public class DiscoveryAdvertisement implements Runnable {
private final static Logger log = Logger.getLogger(DiscoveryAdvertisement.class);
private static boolean MATCH_IP = true;
static {
String prop = System.getProperty("net.sbbi.upnp.ddos.matchip");
if (prop != null && prop.equals("false"))
MATCH_IP = false;
}
private static final int DEFAULT_TIMEOUT = 250;
public final static int EVENT_SSDP_ALIVE = 0;
public final static int EVENT_SSDP_BYE_BYE = 1;
private final static String NTS_SSDP_ALIVE = "ssdp:alive";
private final static String NTS_SSDP_BYE_BYE = "ssdp:byebye";
private final static String NT_ALL_EVENTS = "DiscoveryAdvertisement:nt:allevents";
private final Map<String, Set<DiscoveryEventHandler>> byeByeRegistered = new HashMap<String, Set<DiscoveryEventHandler>>();
private final Map<String, Set<DiscoveryEventHandler>> aliveRegistered = new HashMap<String, Set<DiscoveryEventHandler>>();
private final Map<String, InetAddress> USNPerIP = new HashMap<String, InetAddress>();
private final Object REGISTRATION_PROCESS = new Object();
private final static DiscoveryAdvertisement singleton = new DiscoveryAdvertisement();
private boolean inService = false;
private boolean daemon = true;
private java.net.MulticastSocket skt;
private DatagramPacket input;
private DiscoveryAdvertisement() {
}
public final static DiscoveryAdvertisement getInstance() {
return singleton;
}
public void setDaemon(boolean daemon) {
this.daemon = daemon;
}
/**
* Registers an event category sent by UPNP devices
*
* @param notificationEvent
* the event type, either DiscoveryAdvertisement.EVENT_SSDP_ALIVE or
* DiscoveryAdvertisement.EVENT_SSDP_BYE_BYE
* @param nt
* the type of device advertisement, upnp:rootdevice will return you all advertisement in relation with
* nt upnp:rootdevice a null value specify that all nt type are wanted
* @param eventHandler
* the events handler, this objet will receive notifications..
* @throws IOException
* if an error ocurs when the SSDP events listeners threads starts
*/
public void registerEvent(int notificationEvent, String nt, DiscoveryEventHandler eventHandler) throws IOException {
synchronized (REGISTRATION_PROCESS) {
if (!inService)
startDevicesListenerThread();
if (nt == null)
nt = NT_ALL_EVENTS;
if (notificationEvent == EVENT_SSDP_ALIVE) {
Set<DiscoveryEventHandler> handlers = aliveRegistered.get(nt);
if (handlers == null) {
handlers = new HashSet<DiscoveryEventHandler>();
aliveRegistered.put(nt, handlers);
}
handlers.add(eventHandler);
} else if (notificationEvent == EVENT_SSDP_BYE_BYE) {
Set<DiscoveryEventHandler> handlers = byeByeRegistered.get(nt);
if (handlers == null) {
handlers = new HashSet<DiscoveryEventHandler>();
byeByeRegistered.put(nt, handlers);
}
handlers.add(eventHandler);
} else {
throw new IllegalArgumentException("Unknown notificationEvent type");
}
}
}
/**
* Unregisters an event category sent by UPNP devices
*
* @param notificationEvent
* the event type, either DiscoveryAdvertisement.EVENT_SSDP_ALIVE or
* DiscoveryAdvertisement.EVENT_SSDP_BYE_BYE
* @param nt
* the type of device advertisement, upnp:rootdevice will unregister all advertisement in relation with
* nt upnp:rootdevice a null value specify that all nt type are unregistered
* @param eventHandler
* the events handler that needs to be unregistred.
*/
public void unRegisterEvent(int notificationEvent, String nt, DiscoveryEventHandler eventHandler) {
synchronized (REGISTRATION_PROCESS) {
if (nt == null)
nt = NT_ALL_EVENTS;
if (notificationEvent == EVENT_SSDP_ALIVE) {
Set<DiscoveryEventHandler> handlers = aliveRegistered.get(nt);
if (handlers != null) {
handlers.remove(eventHandler);
if (handlers.size() == 0) {
aliveRegistered.remove(nt);
}
}
} else if (notificationEvent == EVENT_SSDP_BYE_BYE) {
Set<DiscoveryEventHandler> handlers = byeByeRegistered.get(nt);
if (handlers != null) {
handlers.remove(eventHandler);
if (handlers.size() == 0) {
byeByeRegistered.remove(nt);
}
}
} else {
throw new IllegalArgumentException("Unknown notificationEvent type");
}
if (aliveRegistered.size() == 0 && byeByeRegistered.size() == 0) {
stopDevicesListenerThread();
}
}
}
private void startDevicesListenerThread() throws IOException {
synchronized (singleton) {
if (!inService) {
this.startMultiCastSocket();
Thread deamon = new Thread(this, "DiscoveryAdvertisement daemon");
deamon.setDaemon(daemon);
deamon.start();
// wait for the thread to be started
while (!inService) {
// let's wait a few ms
try {
Thread.sleep(2);
} catch (InterruptedException ex) {
// don t care
}
}
}
}
}
private void stopDevicesListenerThread() {
synchronized (singleton) {
inService = false;
}
}
private void startMultiCastSocket() throws IOException {
skt = new java.net.MulticastSocket(null);
skt.bind(new InetSocketAddress(InetAddress.getByName("0.0.0.0"), Discovery.SSDP_PORT));
skt.setTimeToLive(Discovery.DEFAULT_TTL);
skt.setSoTimeout(DEFAULT_TIMEOUT);
skt.joinGroup(InetAddress.getByName(Discovery.SSDP_IP));
byte[] buf = new byte[2048];
input = new DatagramPacket(buf, buf.length);
}
public void run() {
if (!Thread.currentThread().getName().equals("DiscoveryAdvertisement daemon")) {
throw new RuntimeException("No right to call this method");
}
inService = true;
while (inService) {
try {
listenBroadCast();
} catch (SocketTimeoutException ex) {
// ignoring
} catch (IOException ioEx) {
log.error("IO Exception during UPNP DiscoveryAdvertisement messages listening thread", ioEx);
} catch (Exception ex) {
log.error("Fatal Error during UPNP DiscoveryAdvertisement messages listening thread, thread will exit", ex);
inService = false;
aliveRegistered.clear();
byeByeRegistered.clear();
USNPerIP.clear();
}
}
try {
skt.leaveGroup(InetAddress.getByName(Discovery.SSDP_IP));
skt.close();
} catch (Exception ex) {
// ignoring
}
}
private void listenBroadCast() throws IOException {
skt.receive(input);
InetAddress from = input.getAddress();
String received = new String(input.getData(), input.getOffset(), input.getLength());
HttpResponse msg = null;
try {
msg = new HttpResponse(received);
} catch (IllegalArgumentException ex) {
// crappy http sent
if (log.isDebugEnabled())
log.debug("Skipping uncompliant HTTP message " + received);
return;
}
String header = msg.getHeader();
if (header != null && header.startsWith("NOTIFY")) {
if (log.isDebugEnabled())
log.debug(received);
String ntsField = msg.getHTTPHeaderField("nts");
if (ntsField == null || ntsField.trim().length() == 0) {
if (log.isDebugEnabled())
log.debug("Skipping SSDP message, missing HTTP header 'ntsField' field");
return;
}
if (ntsField.equals(NTS_SSDP_ALIVE)) {
String deviceDescrLoc = msg.getHTTPHeaderField("location");
if (deviceDescrLoc == null || deviceDescrLoc.trim().length() == 0) {
if (log.isDebugEnabled())
log.debug("Skipping SSDP message, missing HTTP header 'location' field");
return;
}
URL loc = new URL(deviceDescrLoc);
if (MATCH_IP) {
InetAddress locHost = InetAddress.getByName(loc.getHost());
if (!from.equals(locHost)) {
log.warn("Discovery message sender IP " + from +
" does not match device description IP " + locHost +
" skipping message, set the net.sbbi.upnp.ddos.matchip system property" +
" to false to avoid this check");
return;
}
}
String nt = msg.getHTTPHeaderField("nt");
if (nt == null || nt.trim().length() == 0) {
if (log.isDebugEnabled())
log.debug("Skipping SSDP message, missing HTTP header 'nt' field");
return;
}
String maxAge = msg.getHTTPFieldElement("Cache-Control", "max-age");
if (maxAge == null || maxAge.trim().length() == 0) {
if (log.isDebugEnabled())
log.debug("Skipping SSDP message, missing HTTP header 'max-age' field");
return;
}
String usn = msg.getHTTPHeaderField("usn");
if (usn == null || usn.trim().length() == 0) {
if (log.isDebugEnabled())
log.debug("Skipping SSDP message, missing HTTP header 'usn' field");
return;
}
USNPerIP.put(usn, from);
String udn = usn;
int index = udn.indexOf("::");
if (index != -1)
udn = udn.substring(0, index);
synchronized (REGISTRATION_PROCESS) {
Set<DiscoveryEventHandler> handlers = aliveRegistered.get(NT_ALL_EVENTS);
if (handlers != null) {
for (Iterator<DiscoveryEventHandler> i = handlers.iterator(); i.hasNext();) {
DiscoveryEventHandler eventHandler = i.next();
eventHandler.eventSSDPAlive(usn, udn, nt, maxAge, loc);
}
}
handlers = aliveRegistered.get(nt);
if (handlers != null) {
for (Iterator<DiscoveryEventHandler> i = handlers.iterator(); i.hasNext();) {
DiscoveryEventHandler eventHandler = i.next();
eventHandler.eventSSDPAlive(usn, udn, nt, maxAge, loc);
}
}
}
} else if (ntsField.equals(NTS_SSDP_BYE_BYE)) {
String usn = msg.getHTTPHeaderField("usn");
if (usn == null || usn.trim().length() == 0) {
if (log.isDebugEnabled())
log.debug("Skipping SSDP message, missing HTTP header 'usn' field");
return;
}
String nt = msg.getHTTPHeaderField("nt");
if (nt == null || nt.trim().length() == 0) {
if (log.isDebugEnabled())
log.debug("Skipping SSDP message, missing HTTP header 'nt' field");
return;
}
InetAddress originalAliveSenderIp = USNPerIP.get(usn);
if (originalAliveSenderIp != null) {
// we check that the sender ip of message for the usn
// match the sender ip of the alive message for wich the usn
// has been received
if (!originalAliveSenderIp.equals(from)) {
// someone else is trying to say that the usn is leaving
// since IP do not match we skip the message
return;
}
}
String udn = usn;
int index = udn.indexOf("::");
if (index != -1)
udn = udn.substring(0, index);
synchronized (REGISTRATION_PROCESS) {
Set<DiscoveryEventHandler> handlers = byeByeRegistered.get(NT_ALL_EVENTS);
if (handlers != null) {
for (Iterator<DiscoveryEventHandler> i = handlers.iterator(); i.hasNext();) {
DiscoveryEventHandler eventHandler = i.next();
eventHandler.eventSSDPByeBye(usn, udn, nt);
}
}
handlers = byeByeRegistered.get(nt);
if (handlers != null) {
for (Iterator<DiscoveryEventHandler> i = handlers.iterator(); i.hasNext();) {
DiscoveryEventHandler eventHandler = i.next();
eventHandler.eventSSDPByeBye(usn, udn, nt);
}
}
}
} else {
log.warn("Unvalid NTS field value (" + ntsField + ") received in NOTIFY message :" + received);
}
}
}
}