Пример #1
0
		/// <summary>
		/// Adds a question to the request to be sent to the DNS server.
		/// </summary>
		/// <param name="question">The question to add to the request</param>
		public void AddQuestion(Question question)
		{
			// abandon if null
			if (question == null) throw new ArgumentNullException("question");

			// add this question to our collection
			_questions.Add(question);
		}
Пример #2
0
		/// <summary>
		/// Construct a Response object from the supplied byte array
		/// </summary>
		/// <param name="message">a byte array returned from a DNS server query</param>
		internal Response(byte[] message)
		{
			// the bit flags are in bytes 2 and 3
			byte flags1 = message[2];
			byte flags2 = message[3];

			// get return code from lowest 4 bits of byte 3
			int returnCode = flags2 & 15;
				
			// if its in the reserved section, set to other
			if (returnCode > 6) returnCode = 6;
			_returnCode = (ReturnCode)returnCode;

			// other bit flags
			_authoritativeAnswer = ((flags1 & 4) != 0);
			_recursionAvailable = ((flags2 & 128) != 0);
			_truncated = ((flags1 & 2) != 0);

			// create the arrays of response objects
			_questions = new Question[GetShort(message, 4)];
			_answers = new Answer[GetShort(message, 6)];
			_nameServers = new NameServer[GetShort(message, 8)];
			_additionalRecords = new AdditionalRecord[GetShort(message, 10)];

			// need a pointer to do this, position just after the header
			Pointer pointer = new Pointer(message, 12);

			// and now populate them, they always follow this order
			for (int index = 0; index < _questions.Length; index++)
			{
				try
				{
					// try to build a quesion from the response
					_questions[index] = new Question(pointer);
				}
				catch (Exception ex)
				{
					// something grim has happened, we can't continue
					throw new InvalidResponseException(ex);
				}
			}
			for (int index = 0; index < _answers.Length; index++)
			{
				_answers[index] = new Answer(pointer);
			}
			for (int index = 0; index < _nameServers.Length; index++)
			{
				_nameServers[index] = new NameServer(pointer);
			}
			for (int index = 0; index < _additionalRecords.Length; index++)
			{
				_additionalRecords[index] = new AdditionalRecord(pointer);
			}
		}