private Message
sendAXFR(Message query) throws IOException {
    Name qname = query.getQuestion().getName();
    ZoneTransferIn xfrin = ZoneTransferIn.newAXFR(qname, address, tsig);
    xfrin.setTimeout((int)(getTimeout() / 1000));
    xfrin.setLocalAddress(localAddress);
    try {
        xfrin.run();
    }
    catch (ZoneTransferException e) {
        throw new WireParseException(e.getMessage());
    }
    List records = xfrin.getAXFR();
    Message response = new Message(query.getHeader().getID());
    response.getHeader().setFlag(Flags.AA);
    response.getHeader().setFlag(Flags.QR);
    response.addRecord(query.getQuestion(), Section.QUESTION);
    Iterator it = records.iterator();
    while (it.hasNext())
        response.addRecord((Record)it.next(), Section.ANSWER);
    return response;
}
 

/**
 * Dns lookup more efficient than the INetAddress.getHostName(ip)
 *
 * @param hostIp
 * @return
 * @throws IOException
 */
public String dnsLookup(final String hostIp) {
	try {
		final Name name = ReverseMap.fromAddress(hostIp);
		final int type = Type.PTR;
		final int dclass = DClass.IN;
		final Record rec = Record.newRecord(name, type, dclass);
		final Message query = Message.newQuery(rec);

		final Message response = _resolver.send(query);

		final Record[] answers = response.getSectionArray(Section.ANSWER);
		if (answers.length > 0) {
			String ret = answers[0].rdataToString();
			if (ret.endsWith(".")) {
				ret = ret.substring(0, ret.length() - 1);
			}
			return ret;
		}
	} catch (final IOException e) {
		LOGGER.warn("Failed to resolve hostname for " + hostIp, e);
	}
	return UNKNOWN_HOST;
}
 

private Message messageWithNodes(String query, String[] names) throws TextParseException {
  Name queryName = Name.fromString(query);
  Record question = Record.newRecord(queryName, Type.SRV, DClass.IN);
  Message queryMessage = Message.newQuery(question);
  Message result = new Message();
  result.setHeader(queryMessage.getHeader());
  result.addRecord(question, Section.QUESTION);

  for (String name1 : names) {
    result.addRecord(
        new SRVRecord(queryName, DClass.IN, 1, 1, 1, 8080, Name.fromString(name1)),
        Section.ANSWER);
  }

  return result;
}
 

void doProhibit(Tokenizer st) throws IOException {
  Tokenizer.Token token;
  Name name;
  Record record;
  int type;

  name = st.getName(zone);
  token = st.get();
  if (token.isString()) {
    if ((type = Type.value(token.value)) < 0) {
      throw new IOException("Invalid type: " + token.value);
    }
  } else {
    type = Type.ANY;
  }
  record = Record.newRecord(name, type, DClass.NONE, 0);
  query.addRecord(record, Section.PREREQ);
  print(record);
}
 

static void doAXFR(Message response) {
  System.out.println("; java dig 0.0 <> " + name + " axfr");
  if (response.isSigned()) {
    System.out.print(";; TSIG ");
    if (response.isVerified()) {
      System.out.println("ok");
    } else {
      System.out.println("failed");
    }
  }

  if (response.getRcode() != Rcode.NOERROR) {
    System.out.println(response);
    return;
  }

  for (Record record : response.getSection(Section.ANSWER)) {
    System.out.println(record);
  }

  System.out.print(";; done (");
  System.out.print(response.getHeader().getCount(Section.ANSWER));
  System.out.print(" records, ");
  System.out.print(response.getHeader().getCount(Section.ADDITIONAL));
  System.out.println(" additional)");
}
 

static void	doAXFR(Message response) throws IOException {
	System.out.println("; java dig 0.0 <> " + name + " axfr");
	if (response.isSigned()) {
		System.out.print(";; TSIG ");
		if (response.isVerified())
			System.out.println("ok");
		else
			System.out.println("failed");
	}

	if (response.getRcode() != Rcode.NOERROR) {
		System.out.println(response);
		return;
	}

	Record [] records = response.getSectionArray(Section.ANSWER);
	for (int i = 0; i < records.length; i++)
		System.out.println(records[i]);

	System.out.print(";; done (");
	System.out.print(response.getHeader().getCount(Section.ANSWER));
	System.out.print(" records, ");
	System.out.print(response.getHeader().getCount(Section.ADDITIONAL));
	System.out.println(" additional)");
}
 

private static String reverseDnsLookupUsingDnsJavaSimpleResolver(long ipAddress) throws IOException {
    String result = null;
    byte[] address = convertLongAddressToBuf(ipAddress);
    Name name = ReverseMap.fromAddress(InetAddress.getByAddress(address));
    Record record = Record.newRecord(name, Type.PTR, DClass.IN);
    Message query = Message.newQuery(record);
    Message response = simpleResolver.send(query);
    Record[] answers = response.getSectionArray(Section.ANSWER);
    if (answers.length != 0) {
        // If PTR-record exists this will be at index 1 or above (more than one PTR-record may exist)
        Record answer = (answers.length > 1) ? answers[1] : answers[0];  
        result = answer.rdataToString();
        // remove trailing "."
        result = result.endsWith(".") ? result.substring(0, result.length() - 1) : result;
    } else {
        throw new IOException("Empty DNS response.");
    }
    return result;
}
 

@Override
protected Boolean doInBackground(String... args) {
    //main();
    if (args.length != 1) return false;
    String name = args[0];
    if ((name == null) || (name.isEmpty()))
        return false; //pointless trying to lookup nothing
    Timber.d("Resolving %s", name);
    try {
        SimpleResolver sr = new SimpleResolver(DNSSEC_SERVERS[new Random().nextInt(DNSSEC_SERVERS.length)]);
        ValidatingResolver vr = new ValidatingResolver(sr);
        vr.setTimeout(0, DNS_LOOKUP_TIMEOUT);
        vr.loadTrustAnchors(new ByteArrayInputStream(ROOT.getBytes("ASCII")));
        Record qr = Record.newRecord(Name.fromConstantString(name + "."), Type.TXT, DClass.IN);
        Message response = vr.send(Message.newQuery(qr));
        final int rcode = response.getRcode();
        if (rcode != Rcode.NOERROR) {
            Timber.i("Rcode: %s", Rcode.string(rcode));
            for (RRset set : response.getSectionRRsets(Section.ADDITIONAL)) {
                if (set.getName().equals(Name.root) && set.getType() == Type.TXT
                        && set.getDClass() == ValidatingResolver.VALIDATION_REASON_QCLASS) {
                    Timber.i("Reason:  %s", ((TXTRecord) set.first()).getStrings().get(0));
                }
            }
            return false;
        } else {
            dnssec = response.getHeader().getFlag(Flags.AD);
            for (Record record : response.getSectionArray(Section.ANSWER)) {
                if (record.getType() == Type.TXT) {
                    txts.addAll(((TXTRecord) record).getStrings());
                }
            }
        }
    } catch (IOException | IllegalArgumentException ex) {
        return false;
    }
    return true;
}
 

private ImmutableList<Record> findUpdateRecords(
    Update update, String resourceName, int recordType) {
  for (RRset set : update.getSectionRRsets(Section.UPDATE)) {
    if (set.getName().toString().equals(resourceName) && set.getType() == recordType) {
      return fixIterator(Record.class, set.rrs());
    }
  }
  assertWithMessage(
          "No record set found for resource '%s' type '%s'",
          resourceName, Type.string(recordType))
      .fail();
  throw new AssertionError();
}
 

private Message messageWithRCode(String query, int rcode) throws TextParseException {
  Name queryName = Name.fromString(query);
  Record question = Record.newRecord(queryName, Type.SRV, DClass.IN);
  Message queryMessage = Message.newQuery(question);
  Message result = new Message();
  result.setHeader(queryMessage.getHeader());
  result.addRecord(question, Section.QUESTION);

  result.getHeader().setRcode(rcode);

  return result;
}
 

void doRequire(Tokenizer st) throws IOException {
  Tokenizer.Token token;
  Name name;
  Record record;
  int type;

  name = st.getName(zone);
  token = st.get();
  if (token.isString()) {
    if ((type = Type.value(token.value)) < 0) {
      throw new IOException("Invalid type: " + token.value);
    }
    token = st.get();
    boolean iseol = token.isEOL();
    st.unget();
    if (!iseol) {
      record = Record.fromString(name, type, defaultClass, 0, st, zone);
    } else {
      record = Record.newRecord(name, type, DClass.ANY, 0);
    }
  } else {
    record = Record.newRecord(name, Type.ANY, DClass.ANY, 0);
  }

  query.addRecord(record, Section.PREREQ);
  print(record);
}
 

void doDelete(Tokenizer st) throws IOException {
  Tokenizer.Token token;
  String s;
  Name name;
  Record record;
  int type;

  name = st.getName(zone);
  token = st.get();
  if (token.isString()) {
    s = token.value;
    if (DClass.value(s) >= 0) {
      s = st.getString();
    }
    if ((type = Type.value(s)) < 0) {
      throw new IOException("Invalid type: " + s);
    }
    token = st.get();
    boolean iseol = token.isEOL();
    st.unget();
    if (!iseol) {
      record = Record.fromString(name, type, DClass.NONE, 0, st, zone);
    } else {
      record = Record.newRecord(name, type, DClass.ANY, 0);
    }
  } else {
    record = Record.newRecord(name, Type.ANY, DClass.ANY, 0);
  }

  query.addRecord(record, Section.UPDATE);
  print(record);
}
 

private void addCacheNS(Message response, Cache cache, Name name) {
  SetResponse sr = cache.lookupRecords(name, Type.NS, Credibility.HINT);
  if (!sr.isDelegation()) {
    return;
  }
  RRset nsRecords = sr.getNS();
  for (Record r : nsRecords.rrs()) {
    response.addRecord(r, Section.AUTHORITY);
  }
}
 

private void addGlue(Message response, Name name, int flags) {
  RRset a = findExactMatch(name, Type.A, DClass.IN, true);
  if (a == null) {
    return;
  }
  addRRset(name, response, a, Section.ADDITIONAL, flags);
}
 

byte[] buildErrorMessage(Header header, int rcode, Record question) {
  Message response = new Message();
  response.setHeader(header);
  for (int i = 0; i < 4; i++) {
    response.removeAllRecords(i);
  }
  if (rcode == Rcode.SERVFAIL) {
    response.addRecord(question, Section.QUESTION);
  }
  header.setRcode(rcode);
  return response.toWire();
}
 

private void
applyEDNS(Message query) {
    if (queryOPT == null || query.getOPT() != null)
        return;
    query.addRecord(queryOPT, Section.ADDITIONAL);
}
 

private void assertThatUpdatedZoneIs(Update update, String zoneName) {
  Record[] zoneRecords = update.getSectionArray(Section.ZONE);
  assertThat(zoneRecords[0].getName().toString()).isEqualTo(zoneName);
}
 

private void assertThatTotalUpdateSetsIs(Update update, int count) {
  assertThat(update.getSectionRRsets(Section.UPDATE)).hasLength(count);
}
 

void doAdd(Tokenizer st) throws IOException {
  Record record = parseRR(st, defaultClass, defaultTTL);
  query.addRecord(record, Section.UPDATE);
  print(record);
}
 

void doGlue(Tokenizer st) throws IOException {
  Record record = parseRR(st, defaultClass, defaultTTL);
  query.addRecord(record, Section.ADDITIONAL);
  print(record);
}
 

boolean doAssert(Tokenizer st) throws IOException {
  String field = st.getString();
  String expected = st.getString();
  String value = null;
  boolean flag = true;
  int section;

  if (response == null) {
    print("No response has been received");
    return true;
  }
  if (field.equalsIgnoreCase("rcode")) {
    int rcode = response.getHeader().getRcode();
    if (rcode != Rcode.value(expected)) {
      value = Rcode.string(rcode);
      flag = false;
    }
  } else if (field.equalsIgnoreCase("serial")) {
    List<Record> answers = response.getSection(Section.ANSWER);
    if (answers.isEmpty() || !(answers.get(0) instanceof SOARecord)) {
      print("Invalid response (no SOA)");
    } else {
      SOARecord soa = (SOARecord) answers.get(0);
      long serial = soa.getSerial();
      if (serial != Long.parseLong(expected)) {
        value = Long.toString(serial);
        flag = false;
      }
    }
  } else if (field.equalsIgnoreCase("tsig")) {
    if (response.isSigned()) {
      if (response.isVerified()) {
        value = "ok";
      } else {
        value = "failed";
      }
    } else {
      value = "unsigned";
    }
    if (!value.equalsIgnoreCase(expected)) {
      flag = false;
    }
  } else if ((section = Section.value(field)) >= 0) {
    int count = response.getHeader().getCount(section);
    if (count != Integer.parseInt(expected)) {
      value = Integer.toString(count);
      flag = false;
    }
  } else {
    print("Invalid assertion keyword: " + field);
  }

  if (!flag) {
    print("Expected " + field + " " + expected + ", received " + value);
    while (true) {
      Tokenizer.Token token = st.get();
      if (!token.isString()) {
        break;
      }
      print(token.value);
    }
    st.unget();
  }
  return flag;
}
 

private void addSOA(Message response, Zone zone) {
  response.addRecord(zone.getSOA(), Section.AUTHORITY);
}
 

private void addNS(Message response, Zone zone, int flags) {
  RRset nsRecords = zone.getNS();
  addRRset(nsRecords.getName(), response, nsRecords, Section.AUTHORITY, flags);
}
 

private void addAdditional(Message response, int flags) {
  addAdditional2(response, Section.ANSWER, flags);
  addAdditional2(response, Section.AUTHORITY, flags);
}
 

byte[] generateReply(Message query, byte[] in, Socket s) {
  Header header;
  boolean badversion;
  int maxLength;
  int flags = 0;

  header = query.getHeader();
  if (header.getFlag(Flags.QR)) {
    return null;
  }
  if (header.getRcode() != Rcode.NOERROR) {
    return errorMessage(query, Rcode.FORMERR);
  }
  if (header.getOpcode() != Opcode.QUERY) {
    return errorMessage(query, Rcode.NOTIMP);
  }

  Record queryRecord = query.getQuestion();

  TSIGRecord queryTSIG = query.getTSIG();
  TSIG tsig = null;
  if (queryTSIG != null) {
    tsig = TSIGs.get(queryTSIG.getName());
    if (tsig == null || tsig.verify(query, in, null) != Rcode.NOERROR) {
      return formerrMessage(in);
    }
  }

  OPTRecord queryOPT = query.getOPT();
  if (s != null) {
    maxLength = 65535;
  } else if (queryOPT != null) {
    maxLength = Math.max(queryOPT.getPayloadSize(), 512);
  } else {
    maxLength = 512;
  }

  if (queryOPT != null && (queryOPT.getFlags() & ExtendedFlags.DO) != 0) {
    flags = FLAG_DNSSECOK;
  }

  Message response = new Message(query.getHeader().getID());
  response.getHeader().setFlag(Flags.QR);
  if (query.getHeader().getFlag(Flags.RD)) {
    response.getHeader().setFlag(Flags.RD);
  }
  response.addRecord(queryRecord, Section.QUESTION);

  Name name = queryRecord.getName();
  int type = queryRecord.getType();
  int dclass = queryRecord.getDClass();
  if (type == Type.AXFR && s != null) {
    return doAXFR(name, query, tsig, queryTSIG, s);
  }
  if (!Type.isRR(type) && type != Type.ANY) {
    return errorMessage(query, Rcode.NOTIMP);
  }

  byte rcode = addAnswer(response, name, type, dclass, 0, flags);
  if (rcode != Rcode.NOERROR && rcode != Rcode.NXDOMAIN) {
    return errorMessage(query, rcode);
  }

  addAdditional(response, flags);

  if (queryOPT != null) {
    int optflags = (flags == FLAG_DNSSECOK) ? ExtendedFlags.DO : 0;
    OPTRecord opt = new OPTRecord((short) 4096, rcode, (byte) 0, optflags);
    response.addRecord(opt, Section.ADDITIONAL);
  }

  response.setTSIG(tsig, Rcode.NOERROR, queryTSIG);
  return response.toWire(maxLength);
}