/// <summary>
/// Construct a new Dns Question
/// </summary>
public DnsRequest(DnsQuestion question)
: base(question)
{
this.Header.IsRequest = true;
this.Header.IsTruncated = false;
this.Header.ResponseCode = DnsStandard.ResponseCode.Success;
}
public InfiniteForwardingException(DnsQuestion question)
{
Question = question;
}
/// <summary>
/// This method always returns a failed result.
/// </summary>
/// <param name="question">The question.</param>
/// <returns>The <see cref="AK.Net.Dns.DnsCacheResult"/> if the operation.</returns>
/// <exception cref="System.ArgumentNullException">
/// Thrown when <paramref name="question"/> is <see langword="null"/>.
/// </exception>
public DnsCacheResult Get(DnsQuestion question)
{
Guard.NotNull(question, "question");
return(DnsCacheResult.Failed);
}
public Task <DnsResourceRecord> this[DnsQuestion question] => Cache[question].ContinueWith(t => t.Result.ToResourceRecord(question));
/// <summary>
/// Provide dummy answers for DNS questions
/// </summary>
/// <param name="question"></param>
/// <returns></returns>
public override void HandleQuestion(DnsQuestion question, ref List<DnsAnswer> answerList)
{
//query.GeoLocation.ToString();
if (question.ZoneType == DnsZoneType.SOA || question.ZoneType == DnsZoneType.ANY)
{
//Console.WriteLine("SOA RECORD");
answerList.Add(new DnsAnswer(question)
{
Record = new SoaDnsRecord(900, "ns1.bunnydns.com", "hostmaster.bunnydns.com", 1, 7200, 3600, 1209600, 3600),
});
}
if (question.ZoneType == DnsZoneType.A || question.ZoneType == DnsZoneType.ANY)
{
//Console.WriteLine("A RECORD");
answerList.Add(new DnsAnswer(question)
{
Record = new ADnsRecord(30, IPAddress.Parse("23.249.224.31")),
});
}
if (question.ZoneType == DnsZoneType.MX || question.ZoneType == DnsZoneType.ANY)
{
//Console.WriteLine("MX RECORD");
answerList.Add(new DnsAnswer(question)
{
Record = new MxRecord(30, 1, "ASPMX.L.GOOGLE.com"),
});
answerList.Add(new DnsAnswer(question)
{
Record = new MxRecord(30, 5, "ALT1.ASPMX.L.GOOGLE.com"),
});
}
// Only do this if NS are requested
if (question.ZoneType == DnsZoneType.NS || question.ZoneType == DnsZoneType.ANY)
{
//Console.WriteLine("NS RECORD");
answerList.Add(new DnsAnswer(question)
{
Record = new NsDnsRecord(3600, "ns1.bunnydns.com")
});
answerList.Add(new DnsAnswer(question)
{
Record = new NsDnsRecord(3600, "ns2.bunnydns.com")
});
}
else if (answerList.Count > 0)
{
//Console.WriteLine("AUTHORITY NS RECORD");
answerList.Add(new DnsAnswer(question)
{
Record = new NsDnsRecord(3600, "ns1.bunnydns.com")
{
IsAuthorityRecord = true,
}
});
answerList.Add(new DnsAnswer(question)
{
Record = new NsDnsRecord(3600, "ns2.bunnydns.com")
{
IsAuthorityRecord = true,
}
});
}
}
private static void WriteQuestion(MemoryStream ms, DnsQuestion question)
{
WriteLabels(ms, question.QNameLabels);
WriteUShort(ms, (ushort)question.QType);
WriteUShort(ms, (ushort)question.QClass);
}
public static ResourceRecord FromQuestion(DnsQuestion question, byte[] data, TimeSpan ttl = default(TimeSpan))
{
return(new ResourceRecord(question.Name, data, question.Type, question.Class, ttl));
}
private async Task <DnsMessage> umleitung_process_request(DnsMessage query)
{
DnsMessage upstreamResponse;
DnsMessage response = query.CreateResponseInstance();
DomainName queryhost = DomainName.Parse(query.Questions[0].Name.ToString());
if ((query.Questions.Count == 1))
{
m_log.WriteLine("[+] Processing " + query.Questions[0].RecordType + " query for " + queryhost);
Boolean match = false;
IPAddress ip4 = null;
IPAddress ip6 = null;
// handle masqueraded entries first
m_masq_config.DNSMasqEntries.ForEach(h =>
{
if (queryhost.ToString().StartsWith(h.name))
{
match = true;
m_log.WriteLine(2, "[d] Using masquerading rules.");
response.ReturnCode = ReturnCode.NoError;
if (query.Questions[0].RecordType == RecordType.A)
{
ip4 = IPAddress.Parse(h.a);
ARecord new_a = new ARecord(query.Questions[0].Name, 666, ip4);
response.AnswerRecords.Add(new_a);
}
else if (query.Questions[0].RecordType == RecordType.Aaaa)
{
ip6 = IPAddress.Parse(h.aaaa);
AaaaRecord new_aaaa = new AaaaRecord(query.Questions[0].Name, 666, ip6);
response.AnswerRecords.Add(new_aaaa);
}
}
});
if (match)
{
return(response);
}
// send query to upstream server
DnsQuestion question = query.Questions[0];
if (!m_props.UseCustomDns)
{
m_log.WriteLine(2, "[d] Using system's DNS servers");
upstreamResponse = await DnsClient.Default.ResolveAsync(
question.Name, question.RecordType, question.RecordClass);
}
else
{
m_props.CustomDnsServers.ForEach(d =>
{
m_log.WriteLine(2, "[d] Using custom DNS servers: " + d.ToString());
});
DnsClient dnsc = new DnsClient(m_props.CustomDnsServers, 10000);
upstreamResponse = await dnsc.ResolveAsync(
question.Name, question.RecordType, question.RecordClass);
}
// if we got an answer, copy it to the message sent to the client
if (upstreamResponse != null && upstreamResponse.AnswerRecords.Count > 0)
{
foreach (DnsRecordBase record in (upstreamResponse.AnswerRecords))
{
response.AnswerRecords.Add(record);
}
foreach (DnsRecordBase record in (upstreamResponse.AdditionalRecords))
{
response.AdditionalRecords.Add(record);
}
}
else
{
// no dns record for queried host
if (upstreamResponse == null)
{
m_log.WriteLine(2, "upstreamResponse == null (timeout?)");
}
}
response.ReturnCode = ReturnCode.NoError;
}
return(response);
}
static DnsMessageBase onDnsQuery(DnsMessageBase message, System.Net.IPAddress clientAddress, ProtocolType protocol)
{
message.IsQuery = false;
DnsMessage query = message as DnsMessage;
DnsMessage answer = null;
if ((query != null) && (query.Questions.Count == 1))
{
//HOOK:
//resolve whatsapp.net subdomains
if (query.Questions[0].RecordType == RecordType.A
&&
(
query.Questions[0].Name == WA_CERT_HOST
||
query.Questions[0].Name == WA_REG_HOST
||
(
//media files
query.Questions[0].Name.StartsWith("mms")
&&
query.Questions[0].Name.EndsWith("whatsapp.net")
)
)
)
{
query.ReturnCode = ReturnCode.NoError;
System.Net.IPAddress localIP = GetIP();
if (localIP != null)
{
query.AnswerRecords.Add(new ARecord(query.Questions[0].Name, 30, localIP));
return(query);
}
}
// send query to upstream server
try
{
DnsQuestion question = query.Questions[0];
answer = DnsClient.Default.Resolve(question.Name, question.RecordType, question.RecordClass);
// if got an answer, copy it to the message sent to the client
if (answer != null)
{
foreach (DnsRecordBase record in (answer.AnswerRecords))
{
query.AnswerRecords.Add(record);
}
foreach (DnsRecordBase record in (answer.AdditionalRecords))
{
query.AnswerRecords.Add(record);
}
query.ReturnCode = ReturnCode.NoError;
return(query);
}
}
catch (Exception e)
{ }
}
// Not a valid query or upstream server did not answer correct
message.ReturnCode = ReturnCode.ServerFailure;
return(message);
}
private DnsMessage GetDotBitAnswerForName(DnsQuestion question)
{
string fqdn = question.Name;
try
{
recursionLevel++;
if (recursionLevel > maxRecursion)
{
ConsoleUtils.WriteWarning("Max recursion reached");
return(null);
}
DomainValue value = GetDomainValue(fqdn);
if (value == null)
{
return(null);
}
if (!string.IsNullOrWhiteSpace(value.@Delegate))
{
ConsoleUtils.WriteWarning("delegate setting not implemented: {0}", value.@Delegate);
}
value.ImportDefaultMap();
if (!string.IsNullOrWhiteSpace(value.Translate))
{
string newLookup;
if (value.Translate.EndsWith("."))
{
newLookup = value.Translate.Substring(0, value.Translate.Length - 1);
}
else
{
newLookup = value.Translate + '.' + fqdn;
}
DnsQuestion newQuestion = new DnsQuestion(newLookup, question.RecordType, question.RecordClass);
return(InternalGetAnswer(newQuestion));
}
DnsMessage answer = null;
if (value.Alias != null)
{
string newLookup;
if (value.Alias == "")
{
var sa = fqdn.Split('.');
newLookup = string.Format("{0}.{1}", sa[sa.Length - 2], sa[sa.Length - 1]);
}
else if (value.Alias.EndsWith(".")) // absolute
{
newLookup = value.Alias.Substring(0, value.Alias.Length - 1);
}
else // sub domain
{
var sa = fqdn.Split('.');
sa[0] = value.Alias;
newLookup = string.Join(".", sa);
}
DnsQuestion newQuestion = new DnsQuestion(newLookup, question.RecordType, question.RecordClass);
DnsMessage toReturn = new DnsMessage();
toReturn.AnswerRecords.Add(new CNameRecord(fqdn, defaultTTL, newLookup));
var additional = InternalGetAnswer(newQuestion);
toReturn.AdditionalRecords = additional.AnswerRecords;
return(toReturn);
}
answer = new DnsMessage()
{
Questions = new List <DnsQuestion>()
{
question
}
};
bool any = question.RecordType == RecordType.Any;
var nsnames = value.Ns;
if (nsnames != null && nsnames.Count() > 0) // NS overrides all
{
List <IPAddress> nameservers = GetNameserverAddresses(nsnames);
if (nameservers.Count() > 0)
{
if (!string.IsNullOrWhiteSpace(value.Translate))
{
fqdn = value.Translate;
}
answer = NameServer.DnsResolve(nameservers, fqdn, question.RecordType, question.RecordClass);
}
}
else
{
if (any || question.RecordType == RecordType.A)
{
var addresses = value.Ips;
if (addresses.Count() > 0)
{
foreach (var address in addresses)
{
answer.AnswerRecords.Add(new ARecord(fqdn, defaultTTL, address));
}
}
}
if (any || question.RecordType == RecordType.Aaaa)
{
var addresses = value.Ip6s;
if (addresses.Count() > 0)
{
foreach (var address in addresses)
{
answer.AnswerRecords.Add(new AaaaRecord(fqdn, defaultTTL, address));
}
}
}
}
return(answer);
}
finally
{
recursionLevel--;
}
}
//private void StoreInCache(DnsQuestion dnsQuestion, List<DnsRecordBase> data,
// MemoryCacheEntryOptions cacheEntryOptions)
//{
// _cacheManager.StoreInCache(dnsQuestion, data, cacheEntryOptions);
//}
private void StoreInCache(DnsQuestion dnsQuestion, List <DnsRecordBase> data)
{
_cacheManager.StoreInCache(dnsQuestion, data);
}
public DnsMessage GetAnswer(DnsQuestion question)
{
lock (lockResolver)
return(InternalGetAnswer(question));
}
private void CheckIPAllowedAccess(IPAddress clientAddress, DnsQuestion question)
{
//impliment client ip checking - throw exception if not allowed.
}
private bool IsRedicted(DnsQuestion question)
{
return((question.Name.Contains(_redirectRecord) || string.IsNullOrEmpty(_redirectRecord)) && question.RecordType == RecordType.A);
}
private bool ForwardMessage(DnsMessage message, IPEndPoint revicepoint, byte[] buf,
IPEndPoint targetNameServer, int queryTimeout,
bool useCompressionMutation)
{
DnsQuestion question = null;
if (message.Questions.Count > 0)
{
question = message.Questions[0];
}
byte[] responseBuffer = null;
try
{
if ((Equals(targetNameServer.Address, IPAddress.Loopback) ||
Equals(targetNameServer.Address, IPAddress.IPv6Loopback)) &&
targetNameServer.Port == ((IPEndPoint)_UdpListener.Client.LocalEndPoint).Port)
{
throw new InfiniteForwardingException(question);
}
byte[] sendBuffer;
if (useCompressionMutation)
{
message.Encode(false, out sendBuffer, true);
}
else
{
sendBuffer = buf;
}
_transactionClients[message.TransactionID] = revicepoint;
// Send to Forwarder
/*await _udpForwarder.SendAsync(sendBuffer, sendBuffer.Length, targetNameServer);*/
_UdpForwarder.Send(sendBuffer, sendBuffer.Length, targetNameServer);
if (_transactionTimeoutCancellationTokenSources.ContainsKey(message.TransactionID))
{
_transactionTimeoutCancellationTokenSources[message.TransactionID].Cancel();
}
MrTe.Threading.Tasks.CancellationTokenSource cancellationTokenSource = new MrTe.Threading.Tasks.CancellationTokenSource();
_transactionTimeoutCancellationTokenSources[message.TransactionID] = cancellationTokenSource;
return(true);
// Timeout task to cancel the request
/*try
* {*/
/*await Task.Delay(queryTimeout, cancellationTokenSource.Token);*/
Task.Delay(queryTimeout, cancellationTokenSource.Token);
if (!_transactionClients.ContainsKey(message.TransactionID))
{
return(false);
}
IPEndPoint ignoreEndPoint;
MrTe.Threading.Tasks.CancellationTokenSource ignoreTokenSource;
/*
* _transactionClients.TryRemove(message.TransactionID, out ignoreEndPoint);
* _transactionTimeoutCancellationTokenSources.TryRemove(message.TransactionID,
* out ignoreTokenSource);
*/
ignoreEndPoint = _transactionClients[message.TransactionID];
ignoreTokenSource = _transactionTimeoutCancellationTokenSources[message.TransactionID];
string warningText = message.Questions.Count > 0
? message.Questions[0].Name + " (Type " + message.Questions[0].RecordType + ")"
: "Transaction #" + message.TransactionID + "";
Logger.Warning("Query timeout for: {0}", warningText);
_transactionClients.Remove(message.TransactionID);
_transactionTimeoutCancellationTokenSources.Remove(message.TransactionID);
/*
* }
* catch (TaskCanceledException)
* {
* }
*/
}
catch (InfiniteForwardingException e)
{
Logger.Warning("[Forwarder.Send] Infinite forwarding detected for: {0} (Type {1})", e.Question.Name,
e.Question.RecordType);
Utils.ReturnDnsMessageServerFailure(message, out responseBuffer);
}
catch (SocketException e)
{
if (e.SocketErrorCode == SocketError.ConnectionReset) // Target name server port unreachable
{
Logger.Warning("[Forwarder.Send] Name server port unreachable: {0}", targetNameServer);
}
else
{
Logger.Error("[Forwarder.Send] Unhandled socket error: {0}", e.Message);
}
Utils.ReturnDnsMessageServerFailure(message, out responseBuffer);
}
catch (Exception e)
{
Logger.Error("[Forwarder] Unexpected exception:\n{0}", e);
Utils.ReturnDnsMessageServerFailure(message, out responseBuffer);
}
// If we got some errors
if (responseBuffer != null)
{
/*await _udpListener.SendAsync(responseBuffer, responseBuffer.Length, originalUdpMessage.RemoteEndPoint);*/
_UdpListener.Send(responseBuffer, responseBuffer.Length, revicepoint);
}
return(true);
}
DnsMessageBase ProcessQuery(DnsMessageBase message, IPAddress clientAddress, ProtocolType protocol)
{
message.IsQuery = false;
DnsMessage query = message as DnsMessage;
ret1 : repcnt++;
if ((query != null) && (query.Questions.Count == 1))
{
// send query to upstream server
DnsQuestion question = query.Questions[0];
Random rnd = new Random();
ret2 : if (enb == null)
{
InitDNS();
goto ret2;
}
else
{
//if (question.Name.Contains("xaapi"))
//{
// message.ReturnCode = ReturnCode.ServerFailure;
// return message;
//}
var tt = from q in hash where q.key == question.Name select q;
if (tt.Any())
{
tts = DateTime.Now - tt.ToList()[0].lastupdtime;
if (tts.TotalHours > 12)
{
tt.ToList()[0].answer = null;
}
//WriteToConsole(question.Name + " returned from hash");
if (tt.ToList()[0].answer != null)
{
tt.ToList()[0].selected++;
return(tt.ToList()[0].answer);
}
}
WriteToConsole(question.Name);
templ.Clear();
for (int i = 0; i < retcnt; i++)
{
ret3 : var q = WeightedRandomization.Choose(enb);
if (!templ.Contains(q))
{
templ.Add(q);
}
else
{
goto ret3;
}
}
System.Threading.Tasks.Parallel.ForEach(templ, (site, state) =>
{
WriteToConsole("Get Info for " + question.Name + " from: " + site.IP);
DnsClient cd = new DnsClient(IPAddress.Parse(site.IP), 1000);
DnsMessage answer = cd.Resolve(question.Name, question.RecordType, question.RecordClass);
if (answer != null)
{
foreach (DnsRecordBase record in (answer.AnswerRecords))
{
lock (query)
{
query.AnswerRecords.Add(record);
}
site.Selects++;
}
foreach (DnsRecordBase record in (answer.AdditionalRecords))
{
lock (query)
{
query.AnswerRecords.Add(record);
}
site.Selects++;
}
lock (query)
{
//site.Weight--;
query.ReturnCode = ReturnCode.NoError;
}
if (tt.Any())
{
tt.ToList()[0].answer = query;
tt.ToList()[0].lastupdtime = DateTime.Now;
tt.ToList()[0].selected++;
}
else
{
var t = new hashitem(question.Name, query);
lock (hash)
{
hash.Add(t);
if (frst)
{
qsample = question;
frst = false;
}
}
}
state.Break();
}
});
System.Threading.Tasks.Parallel.ForEach(templ, (site, state) =>
{
WriteToConsole("Get Info from: " + site.IP);
DnsClient cd = new DnsClient(IPAddress.Parse(site.IP), 1000);
DnsMessage answer = cd.Resolve(question.Name, question.RecordType, question.RecordClass);
if (answer != null)
{
foreach (DnsRecordBase record in (answer.AnswerRecords))
{
lock (query)
{
query.AnswerRecords.Add(record);
}
site.Selects++;
WriteToConsole(record.Name);
}
foreach (DnsRecordBase record in (answer.AdditionalRecords))
{
lock (query)
{
query.AnswerRecords.Add(record);
}
site.Selects++;
WriteToConsole(record.Name);
}
lock (query)
{
site.Weight--;
query.ReturnCode = ReturnCode.NoError;
state.Break();
}
}
});
}
// if got an answer, copy it to the message sent to the client
}
if (query.ReturnCode == ReturnCode.NoError)
{
return(query);
}
if (repcnt > 5)
{
message.ReturnCode = ReturnCode.ServerFailure;
return(message);
}
else
{
goto ret1;
}
}
private async Task ForwardMessage(DnsMessage message, UdpReceiveResult originalUdpMessage,
IPEndPoint targetNameServer, int queryTimeout,
bool useCompressionMutation)
{
DnsQuestion question = null;
if (message.Questions.Count > 0)
{
question = message.Questions[0];
}
byte[] responseBuffer = null;
try
{
if ((Equals(targetNameServer.Address, IPAddress.Loopback) ||
Equals(targetNameServer.Address, IPAddress.IPv6Loopback)) &&
targetNameServer.Port == ((IPEndPoint)_udpListener.Client.LocalEndPoint).Port)
{
throw new InfiniteForwardingException(question);
}
byte[] sendBuffer;
if (useCompressionMutation)
{
message.Encode(false, out sendBuffer, true);
}
else
{
sendBuffer = originalUdpMessage.Buffer;
}
_transactionClients[message.TransactionID] = originalUdpMessage.RemoteEndPoint;
// Send to Forwarder
await _udpForwarder.SendAsync(sendBuffer, sendBuffer.Length, targetNameServer);
if (_transactionTimeoutCancellationTokenSources.ContainsKey(message.TransactionID))
{
_transactionTimeoutCancellationTokenSources[message.TransactionID].Cancel();
}
var cancellationTokenSource = new CancellationTokenSource();
_transactionTimeoutCancellationTokenSources[message.TransactionID] = cancellationTokenSource;
// Timeout task to cancel the request
try
{
await Task.Delay(queryTimeout, cancellationTokenSource.Token);
if (!_transactionClients.ContainsKey(message.TransactionID))
{
return;
}
IPEndPoint ignoreEndPoint;
CancellationTokenSource ignoreTokenSource;
_transactionClients.TryRemove(message.TransactionID, out ignoreEndPoint);
_transactionTimeoutCancellationTokenSources.TryRemove(message.TransactionID,
out ignoreTokenSource);
var warningText = message.Questions.Count > 0
? $"{message.Questions[0].Name} (Type {message.Questions[0].RecordType})"
: $"Transaction #{message.TransactionID}";
Logger.Warning("Query timeout for: {0}", warningText);
}
catch (TaskCanceledException)
{
}
}
catch (InfiniteForwardingException e)
{
Logger.Warning("[Forwarder.Send] Infinite forwarding detected for: {0} (Type {1})", e.Question.Name,
e.Question.RecordType);
Utils.ReturnDnsMessageServerFailure(message, out responseBuffer);
}
catch (SocketException e)
{
if (e.SocketErrorCode == SocketError.ConnectionReset) // Target name server port unreachable
{
Logger.Warning("[Forwarder.Send] Name server port unreachable: {0}", targetNameServer);
}
else
{
Logger.Error("[Forwarder.Send] Unhandled socket error: {0}", e.Message);
}
Utils.ReturnDnsMessageServerFailure(message, out responseBuffer);
}
catch (Exception e)
{
Logger.Error("[Forwarder] Unexpected exception:\n{0}", e);
Utils.ReturnDnsMessageServerFailure(message, out responseBuffer);
}
// If we got some errors
if (responseBuffer != null)
{
await _udpListener.SendAsync(responseBuffer, responseBuffer.Length, originalUdpMessage.RemoteEndPoint);
}
}
public DnsRequestMessage(DnsRequestHeader header, DnsQuestion question)
{
Header = header;
Question = question;
}
/// <summary> /// Returns a list of DnsAnswer objects that will be returned for the given question /// </summary> /// <param name="question"></param> /// <returns></returns> public abstract void HandleQuestion(DnsQuestion question, ref List<DnsAnswer> answerList);
private async Task Server_QueryReceived(object sender, ARSoft.Tools.Net.Dns.QueryReceivedEventArgs e)
{
bool foundQuery = false;
DnsMessage query = e.Query as DnsMessage;
if (query == null)
{
return;
}
DnsMessage response = query.CreateResponseInstance();
try {
C.WriteLine($"DnsServer: Questions: {query.Questions.Count}", true, "DNS");
for (int idx = 0; idx < query.Questions.Count; idx++)
{
var question = query.Questions[idx];
using (var connection = db.Connection()) {
using (var command = new SqliteCommand(
"SELECT * FROM DnsEntries WHERE RecordType = @RecordType AND RecordClass = @RecordClass AND DomainName = @DomainName;", connection)) {
command.Parameters.AddWithValue("@RecordType", question.RecordType.ToString());
command.Parameters.AddWithValue("@RecordClass", question.RecordClass.ToString());
command.Parameters.AddWithValue("@DomainName", question.Name.ToString());
using (var reader = command.ExecuteReader()) {
C.WriteLine($" Questions [{idx:000}] RES({reader.HasRows}): Type({question.RecordType}), Class({question.RecordClass}), {question.Name}", true, "DNS");
//Every new row will create a new dictionary that holds the columns
while (reader.Read())
{
try {
var dnStr = reader["DomainName"] as string;
var dn = DomainName.Parse(dnStr);
if (dn == null)
{
continue;
}
var ttl = (System.Int64)reader["TTL"];
var rt = (RecordType)Enum.Parse(typeof(RecordType), reader["RecordType"] as string);
var rc = (RecordClass)Enum.Parse(typeof(RecordClass), reader["RecordClass"] as string);
if (rt == RecordType.A)
{
if (reader["Address"] == null)
{
continue;
}
var addr = reader["Address"] as string;
var aRec = new ARecord(dn, Convert.ToInt32(ttl), IPAddress.Parse(addr));
response.AnswerRecords.Add(aRec);
foundQuery = true;
}
} catch (Exception ex) {
C.WriteLine($" Questions [{idx:000}]: {C.Red}Exception: {ex.ToString()}", true, "DNS:ERROR");
}
}
}
}
}
}
// Fallback
if (dnsFallback != null && !foundQuery)
{
DnsQuestion question = query.Questions[0];
var resolve = dnsFallback.Resolve(question.Name);
DnsMessage upstreamResponse = await dnsFallback.ResolveAsync(
question.Name, question.RecordType, question.RecordClass);
e.Response = upstreamResponse;
return;
}
response.ReturnCode = ReturnCode.NoError;
} catch (Exception ex) {
response.ReturnCode = ReturnCode.ServerFailure;
C.WriteLine($"{C.Red}{ex.ToString()}", true, "DNS:ERROR");
}
// set the response
e.Response = response;
}