public async Task ResolveService_WithCnameRef()
{
var ns = new NameServer(IPAddress.Loopback, 8600);
var serviceName = "myservice";
var baseName = "service.consul";
var fullQuery = $"{serviceName}.{baseName}";
ushort prio = 99;
ushort weight = 69;
ushort port = 88;
var response = new DnsResponseMessage(new DnsResponseHeader(1234, (int)DnsResponseCode.NoError, 0, 0, 0, 0), 0);
response.AddAnswer(
new SrvRecord(
new ResourceRecordInfo(fullQuery, ResourceRecordType.SRV, QueryClass.IN, 1000, 0),
prio,
weight,
port,
DnsString.Parse(serviceName)));
var targetHost = DnsString.Parse("myservice.localhost.net");
response.AddAdditional(
new CNameRecord(
new ResourceRecordInfo(serviceName, ResourceRecordType.CNAME, QueryClass.IN, 1000, 0),
targetHost));
var client = new LookupClient(ns);
var mock = new Mock <IDnsQuery>();
mock.Setup(p => p.QueryAsync(It.IsAny <string>(), It.IsAny <QueryType>(), It.IsAny <QueryClass>(), It.IsAny <CancellationToken>()))
.Returns(() => Task.FromResult <IDnsQueryResponse>(response.AsQueryResponse(ns, client.Settings)));
var mockClient = mock.Object;
var result = await mockClient.ResolveServiceAsync(baseName, serviceName);
Assert.Single(result);
var first = result.First();
Assert.Equal(targetHost.ToString(), first.HostName);
Assert.Equal((int)port, first.Port);
Assert.Equal((int)prio, first.Priority);
Assert.Equal((int)weight, first.Weight);
}
public void Cache_GetOrAdd()
{
var cache = new ResponseCache(true);
var record = new EmptyRecord(new ResourceRecordInfo("a", ResourceRecordType.A, QueryClass.IN, 100, 100));
var response = new DnsResponseMessage(new DnsResponseHeader(1, 256, 1, 1, 0, 0), 0)
{
Audit = new LookupClientAudit()
};
response.AddAnswer(record);
cache.Add("key", response.AsQueryResponse(new NameServer(IPAddress.Any)));
var item = cache.Get("key", out double?effectiveTtl);
Assert.Equal(item, response.AsQueryResponse(new NameServer(IPAddress.Any)));
Assert.Equal(100 * 1000, effectiveTtl);
}
public void Cache_DoesCacheWithMinimumDefined()
{
var minTtl = 2000;
var cache = new ResponseCache(true, TimeSpan.FromMilliseconds(minTtl));
var record = new EmptyRecord(new ResourceRecordInfo("a", ResourceRecordType.A, QueryClass.IN, 0, 100));
var response = new DnsResponseMessage(new DnsResponseHeader(1, 256, 1, 1, 0, 0), 0);
response.AddAnswer(record);
cache.Add("key", response.AsQueryResponse(new NameServer(IPAddress.Any), null));
var item = cache.Get("key", out double?effectiveTtl);
Assert.NotNull(item);
Assert.Equal(0, item.Answers.First().TimeToLive);
Assert.Equal(minTtl, effectiveTtl);
}
public IDnsQueryResponse GetResponse()
{
var elapsed = Elapsed();
if (elapsed <= 0)
{
return(_response);
}
var response = new DnsResponseMessage(
_response.Header,
_response.MessageSize)
{
Audit = (_response as DnsQueryResponse)?.Audit ?? new LookupClientAudit()
};
foreach (var record in _response.Questions)
{
response.AddQuestion(record);
}
foreach (var record in _response.Answers)
{
var clone = record.Clone();
clone.TimeToLive = clone.TimeToLive - elapsed;
response.AddAnswer(clone);
}
foreach (var record in _response.Additionals)
{
var clone = record.Clone();
clone.TimeToLive = clone.TimeToLive - elapsed;
response.AddAnswer(clone);
}
foreach (var record in _response.Authorities)
{
var clone = record.Clone();
clone.TimeToLive = clone.TimeToLive - elapsed;
response.AddAnswer(clone);
}
var qr = response.AsQueryResponse(_response.NameServer);
return(qr);
}
public void Cache_GetOrAddExists()
{
var cache = new ResponseCache(true);
var record = new EmptyRecord(new ResourceRecordInfo("a", ResourceRecordType.A, QueryClass.IN, 100, 100));
var response = new DnsResponseMessage(new DnsResponseHeader(1, 256, 1, 1, 0, 0), 0);
response.AddAnswer(record);
var success = cache.Add("key", response.AsQueryResponse(new NameServer(IPAddress.Any)));
Assert.True(success);
response.AddAnswer(new EmptyRecord(new ResourceRecordInfo("a", ResourceRecordType.A, QueryClass.IN, 100, 100)));
var fail = cache.Add("key", response.AsQueryResponse(new NameServer(IPAddress.Any)));
Assert.False(fail);
}
public void Cache_SupportsInfinite()
{
var cache = new ResponseCache(true, Timeout.InfiniteTimeSpan);
var record = new EmptyRecord(new ResourceRecordInfo("a", ResourceRecordType.A, QueryClass.IN, 0, 100));
var response = new DnsResponseMessage(new DnsResponseHeader(1, 256, 1, 1, 0, 0), 0)
{
Audit = new LookupClientAudit()
};
response.AddAnswer(record);
cache.Add("key", response.AsQueryResponse(new NameServer(IPAddress.Any)));
var item = cache.Get("key", out double?effectiveTtl);
// should not be null although TTL is zero, mimimum timeout is set to infinite
Assert.Equal(item, response.AsQueryResponse(new NameServer(IPAddress.Any)));
Assert.Equal(int.MaxValue, effectiveTtl);
}
public void Cache_DoesNotCacheIfDisabled()
{
var cache = new ResponseCache(false);
var record = new EmptyRecord(new ResourceRecordInfo("a", ResourceRecordType.A, QueryClass.IN, 100, 100));
var response = new DnsResponseMessage(new DnsResponseHeader(1, 256, 1, 1, 0, 0), 0)
{
Audit = new LookupClientAudit()
};
response.AddAnswer(record);
cache.Add("key", response.AsQueryResponse(new NameServer(IPAddress.Any)));
var item = cache.Get("key", out double?effectiveTtl);
// should be null because cache is disabled and we create null in the second call of GetOrAdd
Assert.Null(item);
Assert.Null(effectiveTtl);
}
public void Cache_EntriesLowestTTLWins()
{
var cache = new ResponseCache(true);
var record = new EmptyRecord(new ResourceRecordInfo("a", ResourceRecordType.A, QueryClass.IN, 1000, 100));
var recordB = new EmptyRecord(new ResourceRecordInfo("a", ResourceRecordType.A, QueryClass.IN, 100, 100));
var recordC = new EmptyRecord(new ResourceRecordInfo("a", ResourceRecordType.A, QueryClass.IN, 0, 100));
var response = new DnsResponseMessage(new DnsResponseHeader(1, 256, 1, 1, 0, 0), 0);
response.AddAnswer(record);
response.AddAdditional(recordB);
response.AddAuthority(recordC);
cache.Add("key", response.AsQueryResponse(new NameServer(IPAddress.Any)));
var item = cache.Get("key");
// should be null because recordC has zero TTL which wins
Assert.Null(item);
}
public void Cache_DoesNotCacheIfZeroTTL()
{
var cache = new ResponseCache(true);
var record = new EmptyRecord(new ResourceRecordInfo("a", ResourceRecordType.A, QueryClass.IN, 0, 100));
var response = new DnsResponseMessage(new DnsResponseHeader(1, 256, 1, 1, 0, 0), 0)
{
Audit = new LookupClientAudit()
};
response.AddAnswer(record);
cache.Add("key", response.AsQueryResponse(new NameServer(IPAddress.Any)));
var item = cache.Get("key", out double?effectiveTtl);
// should be null because ttl of the record is 0 which disables caching for this record
Assert.Null(item);
Assert.Null(effectiveTtl);
}
public void Cache_RespectsMaximumTtl()
{
var maxTtl = 2000;
var cache = new ResponseCache(true, maximumTimeout: TimeSpan.FromMilliseconds(maxTtl));
var record = new EmptyRecord(new ResourceRecordInfo("a", ResourceRecordType.A, QueryClass.IN, 60 * 60 * 24, 100));
var response = new DnsResponseMessage(new DnsResponseHeader(1, 256, 1, 1, 0, 0), 0);
response.AddAnswer(record);
cache.Add("key", response.AsQueryResponse(new NameServer(IPAddress.Any), null));
var item = cache.Get("key", out double?effectiveTtl);
Assert.NotNull(item);
Assert.Equal(1, cache.Count);
Assert.Equal(60 * 60 * 24, item.Answers.First().TimeToLive);
Assert.Equal(maxTtl, effectiveTtl);
}
public void Cache_GetOrAddExists()
{
var cache = new ResponseCache();
var record = new EmptyRecord(new ResourceRecord(DnsString.Parse("a"), ARecord.ResourceRecordType, QueryClass.In, 100, 100));
var response = new DnsResponseMessage(new DnsResponseHeader(1, 256, 1, 1, 0, 0), 0)
{
Audit = new LookupClientAudit()
};
response.AddAnswer(record);
var success = cache.Add("key", response.AsQueryResponse(new NameServer(IPAddress.Any)));
Assert.True(success);
response.AddAnswer(new EmptyRecord(new ResourceRecord(DnsString.Parse("a"), ARecord.ResourceRecordType, QueryClass.In, 100, 100)));
var fail = cache.Add("key", response.AsQueryResponse(new NameServer(IPAddress.Any)));
Assert.False(fail);
}
private async void HandleRequest(byte[] data, IPEndPoint remote)
{
DnsRequestMessage request = null;
try
{
request = DnsRequestMessage.FromArray(data);
OnEvent(OnRequested, new RequestedEventArgs(request, data, remote));
IResponse response = await _coder.Code(request);
OnEvent(OnResponded, new RespondedEventArgs(request, response, data, remote));
await _udp.SendAsync(response.ToArray(), response.Size, remote).WithCancellationTimeout(TimeSpan.FromMilliseconds(UDP_TIMEOUT));
}
catch (SocketException e) { OnError(e); }
catch (ArgumentException e) { OnError(e); }
catch (IndexOutOfRangeException e) { OnError(e); }
catch (OperationCanceledException e) { OnError(e); }
catch (IOException e) { OnError(e); }
catch (ObjectDisposedException e) { OnError(e); }
catch (Model.ResponseException e)
{
IResponse response = e.Response;
if (response == null)
{
response = DnsResponseMessage.FromRequest(request);
}
try
{
await _udp.SendAsync(response.ToArray(), response.Size, remote).WithCancellationTimeout(TimeSpan.FromMilliseconds(UDP_TIMEOUT));
}
catch (SocketException) { }
catch (OperationCanceledException) { }
finally { OnError(e); }
}
}
private async void HandleRequest(string sessionID, byte[] data)
{
DnsRequestMessage request = null;
try
{
request = DnsRequestMessage.FromArray(data);
OnEvent(OnRequested, new RequestedEventArgs(request, data));
IResponse response = await _coder.Code(request);
OnEvent(OnResponded, new RespondedEventArgs(request, response, data));
_udpServer.SendAsync(sessionID, response.ToArray());
}
catch (SocketException e) { OnError(e); }
catch (ArgumentException e) { OnError(e); }
catch (IndexOutOfRangeException e) { OnError(e); }
catch (OperationCanceledException e) { OnError(e); }
catch (IOException e) { OnError(e); }
catch (ObjectDisposedException e) { OnError(e); }
catch (ResponseException e)
{
IResponse response = e.Response;
if (response == null)
{
response = DnsResponseMessage.FromRequest(request);
}
try
{
_udpServer.SendAsync(sessionID, response.ToArray());
}
catch (SocketException) { }
catch (OperationCanceledException) { }
finally { OnError(e); }
}
}
public void Cache_EntriesLowestTTLWins()
{
var cache = new ResponseCache();
var record = new EmptyRecord(new ResourceRecord(DnsString.Parse("a"), ARecord.ResourceRecordType, QueryClass.In, 1000, 100));
var recordB = new EmptyRecord(new ResourceRecord(DnsString.Parse("a"), ARecord.ResourceRecordType, QueryClass.In, 100, 100));
var recordC = new EmptyRecord(new ResourceRecord(DnsString.Parse("a"), ARecord.ResourceRecordType, QueryClass.In, 0, 100));
var response = new DnsResponseMessage(new DnsResponseHeader(1, 256, 1, 1, 0, 0), 0)
{
Audit = new LookupClientAudit()
};
response.AddAnswer(record);
response.AddAdditional(recordB);
response.AddAuthority(recordC);
cache.Add("key", response.AsQueryResponse(new NameServer(IPAddress.Any)));
var item = cache.Get("key", out var effectiveTtl);
// should be null because recordC has zero TTL which wins
Assert.Null(item);
Assert.Null(effectiveTtl);
}
public void Resolve_overload_with_IPEndpoint_and_DnsRequetMessage_should_throw_DnsResponseException_when_header_ids_dont_match()
{
// Arrange.
const string domainNameToResolve = "www.A-Dummy-Domain.com";
string domainNameToResolveRoot = domainNameToResolve + ".";
const ushort headerId = 123; // because we are *only* setting this up in the request header, it should not match with the response header.
DnsRequestHeader header = new DnsRequestHeader(headerId, true, DnsOpCode.Query);
DnsQuestion question = new DnsQuestion(mockDnsString.Object, QueryType.A, QueryClass.IN);
DnsRequestMessage dnsRequestMessage = new DnsRequestMessage(header, question);
IPEndPoint dnsServerIP = new IPEndPoint(IPAddress.Parse("10.0.0.10"), dnsPort53);
mockDnsString.Setup(m => m.Value).Returns(domainNameToResolveRoot);
DnsResponseMessage responseMessage = GetDnsResponseMessage();
mockMessageProcessor.Setup(m => m.ProcessResponse(It.IsAny <ArraySegment <byte> >())).Returns(responseMessage);
IDnsResolver resolver = new DnsResolver(mockCommunicator.Object, mockMessageProcessor.Object);
// Act => Act.
Assert.Throws <DnsResponseException>(() => resolver.Resolve(dnsServerIP, dnsRequestMessage), "Header id mismatch.");
}
public async Task Cache_EntriesLowestTT_Expires()
{
var cache = new ResponseCache(true);
var record = new EmptyRecord(new ResourceRecordInfo("a", ResourceRecordType.A, QueryClass.IN, 1000, 100));
var recordB = new EmptyRecord(new ResourceRecordInfo("a", ResourceRecordType.A, QueryClass.IN, 100, 100));
var recordC = new EmptyRecord(new ResourceRecordInfo("a", ResourceRecordType.A, QueryClass.IN, 1, 100));
var response = new DnsResponseMessage(new DnsResponseHeader(1, 256, 1, 1, 0, 0), 0);
response.AddAnswer(record);
response.AddAdditional(recordB);
response.AddAuthority(recordC);
cache.Add("key", response.AsQueryResponse(new NameServer(IPAddress.Any)));
var item = cache.Get("key");
Assert.NotNull(item);
await Task.Delay(1100);
var item3 = cache.Get("key");
Assert.Null(item3);
}
public async Task Cache_DoesCacheWithMinimumDefined()
{
var minTtl = 2000;
var cache = new ResponseCache(true, TimeSpan.FromMilliseconds(minTtl));
var record = new EmptyRecord(new ResourceRecordInfo("a", ResourceRecordType.A, QueryClass.IN, 1, 100));
var response = new DnsResponseMessage(new DnsResponseHeader(1, 256, 1, 1, 0, 0), 0)
{
Audit = new LookupClientAudit()
};
response.AddAnswer(record);
cache.Add("key", response.AsQueryResponse(new NameServer(IPAddress.Any)));
await Task.Delay(1200);
var item = cache.Get("key", out double?effectiveTtl);
// should not be null although TTL is zero, mimimum timeout is set to 2000ms
// TTL of the record should be zero because the initial TTL is 100
Assert.Equal(0, item.Answers.First().TimeToLive);
Assert.Equal(minTtl, effectiveTtl);
}
public static DnsClientResponse FromArray(IRequest request, byte[] message)
{
DnsResponseMessage response = DnsResponseMessage.FromArray(message);
return(new DnsClientResponse(request, response, message));
}
public void ProcessResponse_should_return_DnsResponseMessage_object_with_2_answers_1_question_only_successfully()
{
// Arrange.
const string domainNameToResolve = "www.microsoft.com";
const string domainNameToResolveRoot = domainNameToResolve + ".";
const string ipAddress = "10.1.1.100";
const string ipAddress1 = "101.0.0.101";
const ushort headerId = 1001;
IDnsString dnsString = new DnsString(domainNameToResolve, domainNameToResolveRoot);
ArraySegment <byte> responseData = GetSampleData(ResponseDataSampleFile.QuestionAndAnswerQuery);
mockReader.SetupSequence(m => m.ReadUInt16NetworkOrder(responseData))
.Returns(headerId) // id
.Returns(33152) // flags
.Returns(1) // questionCount
.Returns(2) // answerCount
.Returns(0) // nameServerCount - setting it to zero for this unit test
.Returns(0) // additionCount
.Returns(1) // QueryType
.Returns(1) // QueryClass
// BaseResourceRecordInfo - answer 1
.Returns(1) // record type
.Returns(1) // query class
.Returns(4) // RDLength
// BaseResourceRecordInfo - answer 2
.Returns(1) // record type
.Returns(1) //query class
.Returns(4); //// RDLength
mockReader.Setup(m => m.ReadUInt32NetworkOrder(responseData)).Returns(12); // ttl - 32bit!!
// question
mockReader.SetupSequence(m => m.ReadQuestionQueryString(responseData))
.Returns(dnsString) // question
.Returns(dnsString) // ReadRecordInfo for answer 1
.Returns(dnsString); // ReadRecordInfo for answer 2
mockReader.SetupSequence(m => m.ReadIPAddress(responseData))
.Returns(IPAddress.Parse(ipAddress)) // answer 1
.Returns(IPAddress.Parse(ipAddress1)); // answer 2
mockReader.SetupSequence(m => m.Index)
.Returns(8).Returns(12) // answer 1
.Returns(8).Returns(12); // answer 2
INetworkMessageProcessor messageProcessor = new DnsQueryMessageProcessor(mockReader.Object, mockDnsString.Object);
// Act.
DnsResponseMessage response = messageProcessor.ProcessResponse(responseData);
// Assert.
Assert.AreEqual(2, response.Answers.Count);
Assert.AreEqual(1, response.Questions.Count);
Assert.AreEqual(0, response.Additionals.Count);
Assert.AreEqual(0, response.Authorities.Count);
Assert.AreEqual(headerId, response.Header.Identifier);
Assert.IsInstanceOf <ARecord>(response.Answers[0]); // first answer record.
Assert.IsInstanceOf <ARecord>(response.Answers[1]); // second answer record.
// second Answer check
ARecord arecord = response.Answers[1] as ARecord;
Assert.AreEqual(domainNameToResolveRoot, response.Answers[1].DomainName.Value);
Assert.AreEqual(ipAddress1, arecord.Address.ToString());
// question check
Assert.AreEqual(QueryClass.IN, response.Questions[0].QuestionClass);
Assert.AreEqual(QueryType.A, response.Questions[0].QuestionType);
Assert.AreEqual(domainNameToResolveRoot, response.Questions[0].QueryName.Value);
}
