public static DnsQuery ReadDnsQuery(BinaryReader reader)
{
String domainName = ReadDomainName(reader);
QueryType qtype = (QueryType)ReadUInt16BE(reader);
QueryClass qclass = (QueryClass)ReadUInt16BE(reader);
DnsQuery query = new DnsQuery(domainName, qtype, qclass);
return(query);
}
/* 4.1.2. Question section format
* 1 1 1 1 1 1
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| |
| / QNAME /
| / /
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| QTYPE |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
| QCLASS |
+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
|
| QNAME
| a domain name represented as a sequence of labels, where
| each label consists of a length octet followed by that
| number of octets. The domain name terminates with the
| zero length octet for the null label of the root. Note
| that this field may be an odd number of octets; no
| padding is used.
*/
public static byte[] EncodeDnsQuery(DnsQuery query)
{
MemoryStream stream = new MemoryStream(256);
BinaryWriter writer = new BinaryWriter(stream);
//QNAME
string[] labels = query.DomainName.Split('.');
foreach (string label in labels)
{
writer.Write((byte)label.Length);
writer.Write(Encoding.ASCII.GetBytes(label));
}
writer.Write((byte)0);
//QTYPE
WriteUInt16BE(writer, (UInt16)query.QueryType);
//QCLASS
WriteUInt16BE(writer, (UInt16)query.QueryClass);
return(stream.ToArray());
}