public void DnsQuestionMsgParserTest()
{
DnsMessage msg = DnsMessageParser.Parse(Convert.FromBase64String(ATypeQueryTestData));
Assert.IsNotNull(msg);
Assert.AreEqual(0xbc96, msg.Id);
Assert.IsTrue(msg.Flags.Length == 16);
Assert.IsTrue(msg.OpCode == OpCode.Query, "OpCode should be a query");
Assert.IsTrue(!msg.IsResponse, "Should be a query");
Assert.IsTrue(!msg.IsTruncated, "Should not be truncated");
Assert.IsTrue(msg.IsReccursionDesired, "Should query recursively");
Assert.IsTrue(!msg.IsNonAuthenticatedDataAcceptable, "Non authenticated data should not be accepted");
Assert.IsTrue(msg.QueryQuestions.Count == 1, "Should contain 1 question");
}
public void DnsQuestionResponseParseTest()
{
var msgBytes = Convert.FromBase64String(ATypeQueryResponseTestData);
DnsMessage msg = DnsMessageParser.Parse(msgBytes);
var converted = DnsMessageParser.GetBytes(msg);
byte[] msgNumsPart = new byte[12];
byte[] msgByteNumsPart = new byte[12];
Buffer.BlockCopy(converted, 0, msgNumsPart, 0, 12);
Buffer.BlockCopy(msgBytes, 0, msgByteNumsPart, 0, 12);
Assert.IsTrue(msgNumsPart.SequenceEqual(msgByteNumsPart), $"{string.Join( ", ", msgNumsPart )} does not equal {string.Join( ", ", msgByteNumsPart )}");
Assert.AreEqual <int>(msgBytes.Length, converted.Length, "Lengths are not equal");
Assert.IsTrue(msgBytes.SequenceEqual(converted));
}
private DnsMessage SendQueryToFirstAvailable(List <IPAddress> dnsAddresses, DnsMessage query)
{
using (UdpClient client = new UdpClient(_clientPortNum, AddressFamily.InterNetwork)) {
var dgram = DnsMessageParser.GetBytes(query);
foreach (var address in dnsAddresses)
{
IPEndPoint dnsEp = new IPEndPoint(address, 53);
client.Send(dgram, dgram.Length, dnsEp);
var responce = DnsMessageParser.Parse(client.Receive(ref dnsEp));
if (responce.IsResponse && responce.AnswerRecords.Count > 0)
{
return(responce);
}
}
}
return(null);
}
