/**
* The method queries a Stun server for a binding for the port and address that <tt>sock</tt> is
* bound on.
*
* @param sock the socket whose port and address we'dlike to resolve (the stun message gets sent
* trhough that socket)
* @return StunAddress the address returned by the stun server or null if an error occurred or no
* address was returned
* @throws IOException if an error occurs while stun4j is using sockets.
* @throws BindException if the port is already in use.
*/
private StunAddress queryStunServer(DatagramSocket sock) throws IOException, BindException {
StunAddress mappedAddress = null;
if (detector != null && useStun) {
mappedAddress = detector.getMappingFor(sock);
if (logger.isTraceEnabled()) {
logger.trace(
"For socket with address "
+ sock.getLocalAddress().getHostAddress()
+ " and port "
+ sock.getLocalPort()
+ " the stun server returned the "
+ "following mapping ["
+ mappedAddress
+ "]");
}
}
return mappedAddress;
}
/**
* Returns an InetAddress instance that represents the localhost, and that a socket can bind upon
* or distribute to peers as a contact address.
*
* @param intendedDestination the destination that we'd like to use the localhost address with.
* @return an InetAddress instance representing the local host, and that a socket can bind upon or
* distribute to peers as a contact address.
*/
public synchronized InetAddress getLocalHost(InetAddress intendedDestination) {
// no point in making sure that the localHostFinderSocket is initialized.
// better let it through a NullPointerException.
InetAddress localHost = null;
localHostFinderSocket.connect(intendedDestination, this.RANDOM_ADDR_DISC_PORT);
localHost = localHostFinderSocket.getLocalAddress();
localHostFinderSocket.disconnect();
// windows socket implementations return the any address so we need to
// find something else here ... InetAddress.getLocalHost seems to work
// better on windows so lets hope it'll do the trick.
if (localHost.isAnyLocalAddress()) {
try {
// all that's inside the if is an ugly IPv6 hack
// (good ol' IPv6 - always causing more problems than it solves.)
if (intendedDestination instanceof Inet6Address) {
// return the first globally routable ipv6 address we find
// on the machine (and hope it's a good one)
Enumeration interfaces = NetworkInterface.getNetworkInterfaces();
while (interfaces.hasMoreElements()) {
NetworkInterface iface = (NetworkInterface) interfaces.nextElement();
Enumeration addresses = iface.getInetAddresses();
while (addresses.hasMoreElements()) {
InetAddress address = (InetAddress) addresses.nextElement();
if (address instanceof Inet6Address) {
if (!address.isAnyLocalAddress()
&& !address.isLinkLocalAddress()
&& !address.isSiteLocalAddress()
&& !address.isLoopbackAddress()) {
return address;
}
}
}
}
} else localHost = InetAddress.getLocalHost();
/** @todo test on windows for ipv6 cases */
} catch (Exception ex) {
// sigh ... ok return 0.0.0.0
logger.warn("Failed to get localhost ", ex);
}
}
return localHost;
}