[jcifs] jcifs problem and wins resolution

[Joe Bentley]

> My servlet runs on the SRVGE03 Windows 2000 Server PDC,
> which also happens to be the DMB; IPCONFIG on SRVGE03 states also that
> it is an H-node, and its Wins "client" configuration points to SRVGE02,
> another
> Windows 2000 Server DC running the Wins server service.
> 
> In conclusion:
> I have the  \01\02__MSBROWSE__\02<01>  entry in my Wins Server
> but even if I don't query the Wins Server:
> I have the  \01\02__MSBROWSE__\02<01> registered on my network (if I type
> NBTSTAT -n on SRVGE03 I see the entry)
> and I should get this name via Broadcast !
> 
> I specified the following properties in my servlet:
>         jcifs.Config.setProperty("jcifs.netbios.wins", "192.168.69.6");
>         jcifs.Config.setProperty("jcifs.netbios.baddr", "192.168.69.255");
>         jcifs.Config.setProperty("jcifs.resolveOrder", "WINS,DNS,BCAST");
> 

I've noticed the same problem too.  It's because you are executing your code
on the PDC and a host cannot broadcast to it self.  

The problem can also be reproduced doing following:
  jcifs.Config.setProperty("jcifs.netbios.baddr", "127.0.0.1");

If you move your code off the DCs, it should work, providing that the baddr
includes at least one DC.  Yeah I know it's a lame work around.  Let me know
if you find a better answer.

That reminds me, the global jcifs.Config.setProperty("jcifs.netbios.baddr")
design doesn't work for me.  I need to be able to pass a broadcast address
into the SmbFile("smb://") call to locally override the jcifs.netbios.baddr
setting.  My jCIFS code is sitting on a gateway machine where I need to
broadcast to separate networks that may have over-lapping domain names.
Currently a single-threaded synchronized block is required to protect the
global baddr value before a broadcast call.

Here's an example:

class CIFSDriver {

	public static String getDomainController(String domain,
		String broadcastAddress) {

		InetAddress	baddr;

		try {
			baddr = InetAddress.getByName(broadcastAddress);
		}
		catch (UnknownHostException e)
		{
			baddr = null;
		}

		try {
			return NbtAddress.getByName(domain, 0x1c, null,
				baddr).getHostAddress();
		}
		catch (UnknownHostException e)
		{
			return null;
		}
	}

	public synchronized static void listDomains(String broadcastAddress)
		throws Exception {

		String oldAddr = jcifs.Config.getProperty("baddr");
		jcifs.Config.setProperty("baddr", broadcastAddress);

		SmbFile connection = new SmbFile("smb://");
		String[] domains = connection.list();
		for (int i = 0; i < domains.length; i++)
			System.out.println(domains[i] + ":" +
				getDomainController(domains[i],
broadcastAddress));

		if (oldAddr != null)
			jcifs.Config.setProperty("baddr", oldAddr);
	}

	public static void main(String[] args) throws Exception {

		listDomains("192.168.50.255");
		listDomains("115.63.255.255");
	}
}

-joe