EDNS0 Client-Subnet

[Deven P. <de...@dn...>]

Hello All,

     New to the list and this may have been answered previously, but I 
didn't find it searching the archives.

Our company is implementing 
http://tools.ietf.org/html/draft-vandergaast-edns-client-ip-01

I am trying to add functionality to one of our Java debugging tools to 
test this functionality, so I have set up a SimpleResolver and used the 
setEDNS() method. When I create the Option instance for the OPTRecord, I 
do it as follows:

InetAddress address = null ;
try {
     address = InetAddress.getByName(sourceField.getText()) ;
     int sourceMask = 32 ;
     int scopeMask = 0 ;
     byte[] family = new byte[2] ;
     family[0] = 0x0 ;
     family[1] = 0x1 ;
     if (Inet4Address.class.isInstance(address)) {
         family[1] = 0x1 ;
     } else {
         family[1] = 0x2 ;
     }
     ByteArrayOutputStream baos = new ByteArrayOutputStream() ;
     baos.write(family) ;
     baos.write(sourceMask) ;
     baos.write(scopeMask) ;
     baos.write(address.getAddress()) ;
     System.out.println(new String(baos.toByteArray())) ;
     Option clientSubnet = new Option(0x50fa, baos.toByteArray()) ;
     ArrayList<Option> options = new ArrayList<Option>() ;
     options.add(clientSubnet) ;
     resolver.setEDNS(0, baos.size(), 0, options);
} catch (UnknownHostException uhe) {
     System.out.println("Source address is set, but is not a valid 
hostname/IP.") ;
}

The problem is that when I attempt to perform the lookup, I get an error:

FORMERR

As far as I can tell, the byte[] format is identical to the format 
specified in the RFC (not that DNSJava is checking) and certainly 
complies with the OPTRecord requirements. Any suggestions?

Worst case scenario, I could just manually send my own message, but I 
hate to re-invent the wheel.

Thanks,

Deven Phillips
Systems Programmer
DNS.com