@@ -26,6 +26,10 @@ public class DNSHelper {
if (value != null && !"".equals(value) && !servers.contains(value))
ip = InetAddress.getByName(value);
servers.add(value);
+ Bundle result = queryDNS(host, ip);
+ if (!result.containsKey("error")) {
+ return result;
+ }
}
} catch (ClassNotFoundException e) {
ip = InetAddress.getByName("8.8.8.8");
@@ -38,71 +42,79 @@ public class DNSHelper {
} catch (InvocationTargetException e) {
ip = InetAddress.getByName("8.8.8.8");
}
-
- Log.d("xmppService","using dns server: "+ip.toString()+" to look up SRV records");
-
+ return queryDNS(host, ip);
+ }
+
+ public static Bundle queryDNS(String host, InetAddress dnsServer) {
Bundle namePort = new Bundle();
- String[] hostParts = host.split("\\.");
- byte[] transId = new byte[2];
- Random random = new Random();
- random.nextBytes(transId);
- byte[] header = { 0x01, 0x20, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00,
- 0x00, 0x01, 0x0c, 0x5f, 0x78, 0x6d, 0x70, 0x70, 0x2d, 0x63,
- 0x6c, 0x69, 0x65, 0x6e, 0x74, 0x04, 0x5f, 0x74, 0x63, 0x70 };
- byte[] rest = { 0x00, 0x00, 0x21, 0x00, 0x01, 0x00, 0x00, 0x29,
- 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
- ByteArrayOutputStream output = new ByteArrayOutputStream();
- output.write(transId);
- output.write(header);
- for (int i = 0; i < hostParts.length; ++i) {
- char[] tmpChars = hostParts[i].toCharArray();
- byte[] tmp = new byte[tmpChars.length];
- for (int j = 0; j < tmpChars.length; ++j) {
- tmp[j] = (byte) tmpChars[j];
- }
- output.write(tmp.length);
- output.write(tmp);
+ try {
+ Log.d("xmppService","using dns server: "+dnsServer.toString()+" to look up "+host);
+ String[] hostParts = host.split("\\.");
+ byte[] transId = new byte[2];
+ Random random = new Random();
+ random.nextBytes(transId);
+ byte[] header = { 0x01, 0x20, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x01, 0x0c, 0x5f, 0x78, 0x6d, 0x70, 0x70, 0x2d, 0x63,
+ 0x6c, 0x69, 0x65, 0x6e, 0x74, 0x04, 0x5f, 0x74, 0x63, 0x70 };
+ byte[] rest = { 0x00, 0x00, 0x21, 0x00, 0x01, 0x00, 0x00, 0x29,
+ 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
+ ByteArrayOutputStream output = new ByteArrayOutputStream();
+ output.write(transId);
+ output.write(header);
+ for (int i = 0; i < hostParts.length; ++i) {
+ char[] tmpChars = hostParts[i].toCharArray();
+ byte[] tmp = new byte[tmpChars.length];
+ for (int j = 0; j < tmpChars.length; ++j) {
+ tmp[j] = (byte) tmpChars[j];
}
- output.write(rest);
- byte[] sendPaket = output.toByteArray();
- int realLenght = sendPaket.length - 11;
- DatagramPacket packet = new DatagramPacket(sendPaket,
- sendPaket.length, ip, 53);
- DatagramSocket datagramSocket = new DatagramSocket();
- datagramSocket.send(packet);
- byte[] receiveData = new byte[1024];
+ output.write(tmp.length);
+ output.write(tmp);
+ }
+ output.write(rest);
+ byte[] sendPaket = output.toByteArray();
+ int realLenght = sendPaket.length - 11;
+ DatagramPacket packet = new DatagramPacket(sendPaket,
+ sendPaket.length, dnsServer, 53);
+ DatagramSocket datagramSocket = new DatagramSocket();
+ datagramSocket.send(packet);
+ byte[] receiveData = new byte[1024];
- DatagramPacket receivePacket = new DatagramPacket(receiveData,
- receiveData.length);
- datagramSocket.setSoTimeout(2000);
- datagramSocket.receive(receivePacket);
- if (receiveData[3]!=-128) {
- namePort.putString("error", "nosrv");
- return namePort;
- }
- namePort.putInt("port",calcPort(receiveData[realLenght + 16],
- receiveData[realLenght + 17]));
- int i = realLenght + 18;
- int wordLenght = 0;
- StringBuilder builder = new StringBuilder();
- while (receiveData[i] != 0) {
- if (wordLenght > 0) {
- builder.append((char) receiveData[i]);
- --wordLenght;
- } else {
- wordLenght = receiveData[i];
- builder.append(".");
- }
- ++i;
- }
- builder.replace(0, 1, "");
- byte type = receiveData[i+1];
- if (type!=-64) {
- namePort.putString("error", "nosrv");
- return namePort;
+ DatagramPacket receivePacket = new DatagramPacket(receiveData,
+ receiveData.length);
+ datagramSocket.setSoTimeout(3000);
+ datagramSocket.receive(receivePacket);
+ if (receiveData[3]!=-128) {
+ namePort.putString("error", "nosrv");
+ return namePort;
+ }
+ namePort.putInt("port",calcPort(receiveData[realLenght + 16],
+ receiveData[realLenght + 17]));
+ int i = realLenght + 18;
+ int wordLenght = 0;
+ StringBuilder builder = new StringBuilder();
+ while (receiveData[i] != 0) {
+ if (wordLenght > 0) {
+ builder.append((char) receiveData[i]);
+ --wordLenght;
+ } else {
+ wordLenght = receiveData[i];
+ builder.append(".");
}
- namePort.putString("name",builder.toString());
+ ++i;
+ }
+ builder.replace(0, 1, "");
+ byte type = receiveData[i+1];
+ if (type!=-64) {
+ namePort.putString("error", "nosrv");
+ return namePort;
+ }
+ namePort.putString("name",builder.toString());
return namePort;
+ } catch (IOException e) {
+ Log.d("xmppService","io execpiton during dns");
+ namePort.putString("error", "nosrv");
+ return namePort;
+ }
}
static int calcPort(byte hb, byte lb) {