more dns fixes. hopefully the last

Daniel Gultsch created

Change summary

src/eu/siacs/conversations/utils/DNSHelper.java | 176 ++++++++++--------
1 file changed, 95 insertions(+), 81 deletions(-)

Detailed changes

src/eu/siacs/conversations/utils/DNSHelper.java 🔗

@@ -17,19 +17,24 @@ public class DNSHelper {
 	public static Bundle getSRVRecord(String host) throws IOException {
 		InetAddress ip = InetAddress.getByName("8.8.8.8");
 		try {
-			Class<?> SystemProperties = Class.forName("android.os.SystemProperties");
-			Method method = SystemProperties.getMethod("get", new Class[] { String.class });
+			Class<?> SystemProperties = Class
+					.forName("android.os.SystemProperties");
+			Method method = SystemProperties.getMethod("get",
+					new Class[] { String.class });
 			ArrayList<String> servers = new ArrayList<String>();
-			for (String name : new String[] { "net.dns1", "net.dns2", "net.dns3", "net.dns4", }) {
-			    String value = (String) method.invoke(null, name);
-			    
-				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;
-			        }
+			for (String name : new String[] { "net.dns1", "net.dns2",
+					"net.dns3", "net.dns4", }) {
+				String value = (String) method.invoke(null, name);
+
+				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");
@@ -44,74 +49,82 @@ public class DNSHelper {
 		}
 		return queryDNS(host, ip);
 	}
-	
+
 	public static Bundle queryDNS(String host, InetAddress dnsServer) {
 		Bundle namePort = new Bundle();
 		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];
+			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(tmp.length);
+				output.write(tmp);
 			}
-			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];
+			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(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;
+			DatagramPacket receivePacket = new DatagramPacket(receiveData,
+					receiveData.length);
+			datagramSocket.setSoTimeout(3000);
+			datagramSocket.receive(receivePacket);
+			if (receiveData[3] != -128) {
+				Log.d("xmppService", "not the right count");
+				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];
+			byte type2 = receiveData[i + 2];
+			if ((type == -64) || (type == type2)) {
+				namePort.putString("name", builder.toString());
+				return namePort;
 			} else {
-				wordLenght = receiveData[i];
-				builder.append(".");
+				Log.d("xmppService", "type=" + type + " type2=" + type2 + " "
+						+ builder.toString());
+				namePort.putString("error", "nosrv");
+				return namePort;
 			}
-			++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");
+			Log.d("xmppService", "io execpiton during dns");
 			namePort.putString("error", "nosrv");
 			return namePort;
 		}
@@ -119,21 +132,22 @@ public class DNSHelper {
 
 	static int calcPort(byte hb, byte lb) {
 		int port = ((int) hb << 8) | ((int) lb & 0xFF);
-		if (port>=0) {
+		if (port >= 0) {
 			return port;
 		} else {
 			return 65536 + port;
 		}
 	}
-	
+
 	final protected static char[] hexArray = "0123456789ABCDEF".toCharArray();
+
 	public static String bytesToHex(byte[] bytes) {
-	    char[] hexChars = new char[bytes.length * 2];
-	    for ( int j = 0; j < bytes.length; j++ ) {
-	        int v = bytes[j] & 0xFF;
-	        hexChars[j * 2] = hexArray[v >>> 4];
-	        hexChars[j * 2 + 1] = hexArray[v & 0x0F];
-	    }
-	    return new String(hexChars);
+		char[] hexChars = new char[bytes.length * 2];
+		for (int j = 0; j < bytes.length; j++) {
+			int v = bytes[j] & 0xFF;
+			hexChars[j * 2] = hexArray[v >>> 4];
+			hexChars[j * 2 + 1] = hexArray[v & 0x0F];
+		}
+		return new String(hexChars);
 	}
 }