import java.io.*;
import java.util.*;
import java.net.*;
+import org.ibex.util.*;
+import org.ibex.net.*;
import org.xbill.DNS.*;
import org.xbill.DNS.Message;
+import javax.naming.*;
+import javax.naming.directory.*;
public class DNSUtil {
return answers.length==0 ? null : answers[0].rdataToString();
}
+ public static InetAddress[] getMailExchangerIPs(String hostName) {
+ InetAddress[] ret;
+ try {
+ Hashtable env = new Hashtable();
+ env.put("java.naming.factory.initial", "com.sun.jndi.dns.DnsContextFactory");
+ DirContext ictx = new InitialDirContext(env);
+ Attributes attrs = ictx.getAttributes(hostName, new String[] { "MX" });
+ Attribute attr = attrs.get("MX");
+ if (attr == null) {
+ ret = new InetAddress[1];
+ try {
+ ret[0] = InetAddress.getByName(hostName);
+ if (ret[0].equals(IP.getIP(127,0,0,1)) || ret[0].isLoopbackAddress()) throw new UnknownHostException();
+ return ret;
+ } catch (UnknownHostException uhe) {
+ Log.warn(DNSUtil.class, "no MX hosts or A record for " + hostName);
+ return new InetAddress[0];
+ }
+ } else {
+ ret = new InetAddress[attr.size()];
+ NamingEnumeration ne = attr.getAll();
+ for(int i=0; ne.hasMore();) {
+ String mx = (String)ne.next();
+ // FIXME we should be sorting here
+ mx = mx.substring(mx.indexOf(" ") + 1);
+ if (mx.charAt(mx.length() - 1) == '.') mx = mx.substring(0, mx.length() - 1);
+ InetAddress ia = InetAddress.getByName(mx);
+ if (ia.equals(IP.getIP(127,0,0,1)) || ia.isLoopbackAddress()) continue;
+ ret[i++] = ia;
+ }
+ }
+ } catch (Exception e) {
+ Log.warn(DNSUtil.class, "couldn't find MX host for " + hostName + " due to");
+ Log.warn(DNSUtil.class, e);
+ return new InetAddress[0];
+ }
+ return ret;
+ }
+
}