public static PackageQuestion FromArray(byte[] clientMessage, int offset)
{
var question = new PackageQuestion {
QNAME = new byte[0]
};
var lastIndex = offset;
for (var i = offset; i < clientMessage.Length; i++)
{
var number = BitConverter.ToInt16(new[] { clientMessage[i], new byte() }, 0);
if (number >= 192)
{
question.QNAME = question.QNAME.Concat(new[] { clientMessage[i], clientMessage[i + 1] }).ToArray();
lastIndex += 2;
break;
}
question.QNAME = question.QNAME.Concat(new[] { clientMessage[i] }).ToArray();
if (clientMessage[i].CompareTo(new byte()) != 0)
{
continue;
}
lastIndex = i;
break;
}
question.QTYPE = BitConverter.ToInt16(new [] { clientMessage[lastIndex + 2], clientMessage[lastIndex + 1] }, 0);
question.QCLASS = BitConverter.ToInt16(new[] { clientMessage[lastIndex + 4], clientMessage[lastIndex + 3] }, 0);
return(question);
}
public static DnsPackage FromArray(byte[] clientMessage)
{
Console.WriteLine(clientMessage.Length);
var header = PackageHeader.FromArray(clientMessage);
Console.WriteLine("HEADER DONE");
var question = PackageQuestion.FromArray(clientMessage, 12);
Console.WriteLine("QUESTION DONE");
var answers = new List <PackageAnswer>();
var lastSize = 12 + question.Size;
for (int i = 0; i < header.ANCOUNT; i++)
{
var answer = PackageAnswer.FromArray(clientMessage, lastSize);
if (answer.Size == 6)
{
break;
}
answers.Add(answer);
lastSize += answer.Size;
}
var auths = new List <PackageAnswer>();
for (int i = 0; i < header.NSCOUNT; i++)
{
var authorityAnswer = PackageAnswer.FromArray(clientMessage, lastSize);
lastSize += authorityAnswer.Size;
authorityAnswer.SetNormalName(clientMessage);
auths.Add(authorityAnswer);
}
var additionals = new List <PackageAnswer>();
for (int i = 0; i < header.ARCOUNT; i++)
{
var additionalAnswer = PackageAnswer.FromArray(clientMessage, lastSize);
lastSize += additionalAnswer.Size;
additionalAnswer.Question.QTYPE = (int)Type.NS;
additionalAnswer.SetNormalName(clientMessage);
additionals.Add(additionalAnswer);
}
foreach (var add in additionals)
{
var q = auths.FirstOrDefault(x => ArraysEquals(x.RDATA, add.Question.QNAME));
if (q != null)
{
add.Question.QNAME = q.Question.QNAME;
}
}
Console.WriteLine("ANSWER DONE");
return(new DnsPackage(header, question, answers)
{
Additionals = additionals, Auth = auths
});
}
public static PackageAnswer FromArray(byte[] clientMessage, int offset)
{
if (clientMessage.Length <= offset + 1)
{
return(new PackageAnswer());
}
var answer = new PackageAnswer {
Question = PackageQuestion.FromArray(clientMessage, offset)
};
answer.TTL = BitConverter.ToInt32(clientMessage.Skip(offset + answer.Question.Size).Take(4).Reverse().ToArray(), 0);
answer.RDLENGTH = BitConverter.ToInt16(clientMessage.Skip(offset + answer.Question.Size + 4).Take(2).Reverse().ToArray(), 0);
answer.RDATA = clientMessage.Skip(offset + answer.Question.Size + 6).Take(answer.RDLENGTH).ToArray();
return(answer);
}
protected bool Equals(PackageQuestion other)
{
return(Equals(Encoding.ASCII.GetString(QNAME), Encoding.ASCII.GetString(other.QNAME)) && TypesEquals(QTYPE, other.QTYPE) && ClassEquals(QCLASS, other.QCLASS));
}
public DnsPackage(PackageHeader header, PackageQuestion question, List <PackageAnswer> answers)
{
Header = header;
Question = question;
Answers = answers;
}