private void SendRecordRequest(string host, DnsType type)
{
DnsLayer dnsLayer =
new DnsLayer
{
Id = 100,
IsResponse = false,
OpCode = DnsOpCode.Query,
IsAuthoritativeAnswer = false,
IsTruncated = false,
IsRecursionDesired = true,
IsRecursionAvailable = false,
FutureUse = false,
IsAuthenticData = false,
IsCheckingDisabled = false,
ResponseCode = DnsResponseCode.NoError,
Queries = new[]
{
new DnsQueryResourceRecord(new DnsDomainName(host),
type, DnsClass.Internet),
},
Answers = null,
Authorities = null,
Additionals = null,
DomainNameCompressionMode = DnsDomainNameCompressionMode.All,
};
ushort port = (ushort)(4050 + _random.Next(0, 1000));
string hashVal = host.ToLower() + ":" + port;
PendingRequests.Add(hashVal);
OSI.Layer4UdpPacket udp = new OSI.Layer4UdpPacket();
udp.Destination = _client.Configuration.DnsServers[0].AsString;
udp.LocalPort = port;
udp.RemotePort = 53;
udp.NextLayers.Add(dnsLayer);
SendPacket(udp);
}
private void SendUdpPacket(OSI.Layer4UdpPacket packet, PacketSentHandler callback)
{
UdpLayer udpLayer =
new UdpLayer
{
SourcePort = packet.LocalPort,
DestinationPort = packet.RemotePort,
Checksum = null, // Will be filled automatically.
CalculateChecksumValue = true,
};
OSI.Layer3Packet l3 = new OSI.Layer3Packet();
l3.Ttl = 255;
l3.SourceIP = Configuration.IpAddress;
l3.Destination = packet.Destination;
foreach (ILayer layer in packet.NextLayers)
{
l3.NextLayers.Add(layer);
}
l3.NextLayers.Insert(0, udpLayer);
SendLayer3Packet(l3, callback);
}
