private void HandleRData(NetBinaryReader nbr)
{
long startPos = nbr.BaseStream.Position;
switch (Type)
{
case (QType.A):
case (QType.AAAA):
recordValue = new IPAddress(nbr.ReadBytes(ByteCount));
break;
/*
case (QType.NS):
case (QType.CNAME):
recordValue = nbr.ReadLblOrPntString();
ReadPadOctets(nbr, startPos);
break;
case (QType.SOA):
recordValue = new SOA(nbr);
ReadPadOctets(nbr, startPos);
break;
*/
default:
recordValue = nbr.ReadBytes(ByteCount);
break;
}
}
public DnsQuestion(NetBinaryReader nbr)
{
List<string> labels = new List<string>();
byte nameLength;
while ((nameLength = nbr.ReadByte()) != 0)
{
string label = string.Empty;
for (int i = 0; i < nameLength; i++)
{
label += (char)nbr.ReadByte();
}
labels.Add(label);
}
QueriedDomainName = string.Join(".", labels);
Type = (QType)nbr.ReadUInt16();
ushort rawClass = nbr.ReadUInt16();
if (rawClass > 65279) rawClass = 0;
else if (rawClass > 4 && rawClass < 252) rawClass = 2;
else if (rawClass > 255 && rawClass < 65280) rawClass = 2;
Class = (DnsClass)rawClass;
}
public IPHeader(byte[] byBuffer, int nReceived)
{
NetBinaryReader nbr = new NetBinaryReader(byBuffer, 0, nReceived);
Version = nbr.ReadNible();
HeaderLength = nbr.ReadNible();
Precedence = (Precedence)nbr.ReadCustomAmount(3);
LowDelay = nbr.ReadBit();
HighThroughput = nbr.ReadBit();
HighRelibility = nbr.ReadBit();
nbr.SkipPadBits();
TotalLength = nbr.ReadUInt16();
Identification = nbr.ReadUInt16();
nbr.ReadBit();
MayFragment = !nbr.ReadBit();
LastFragment = !nbr.ReadBit();
FragmentOffset = (nbr.ReadPadBits() << 3) + nbr.ReadByte();
TTL = nbr.ReadByte();
Protocol = (ProtocolType)nbr.ReadByte();
HeaderChecksum = IPAddress.NetworkToHostOrder(nbr.ReadInt16());
Source = new IPAddress(nbr.ReadBytes(4));
Destination = new IPAddress(nbr.ReadBytes(4));
}
public DnsPacket(Packet packet)
{
Header = (packet.ApplicationHeader as DnsHeader);
if (Header == null) throw new ArgumentException("Non-Dns packet!");
NetBinaryReader nbr = new NetBinaryReader(Header.data);
Questions = new DnsQuestion[Header.QuestionCount];
for (int i = 0; i < Questions.Length; i++)
{
Questions[i] = new DnsQuestion(nbr);
}
Answers = new DnsAnswer[Header.AnswerCount];
for (int i = 0; i < Answers.Length; i++)
{
Answers[i] = new DnsAnswer(nbr);
}
Authority = new DnsAnswer[Header.AuthorityCount];
for (int i = 0; i < Authority.Length; i++)
{
Authority[i] = new DnsAnswer(nbr);
}
Information = new DnsAnswer[Header.AdditionalCount];
for (int i = 0; i < Information.Length; i++)
{
Information[i] = new DnsAnswer(nbr);
}
}
public SOA(NetBinaryReader nbr)
{
PrimaryNS = nbr.ReadLblOrPntString();
AdminMB = nbr.ReadLblOrPntString();
SerialNbr = nbr.ReadUInt32();
RefreshInterval = nbr.ReadUInt32();
RetryInterval = nbr.ReadUInt32();
ExpirationLimit = nbr.ReadUInt32();
MaxTTL = nbr.ReadUInt32();
}
public TcpHeader(byte[] byIpData, int start)
{
NetBinaryReader nbr = new NetBinaryReader(byIpData, start);
SourcePort = nbr.ReadUInt16();
DestinationPort = nbr.ReadUInt16();
SequenceNumber = nbr.ReadUInt32();
AcknowledgmentNumber = nbr.ReadUInt32();
DataOffset = nbr.ReadNible();
nbr.SkipPadBits();
nbr.ReadCustomAmount(2);
URG = nbr.ReadBit();
ACK = nbr.ReadBit();
PSH = nbr.ReadBit();
RST = nbr.ReadBit();
SYN = nbr.ReadBit();
FIN = nbr.ReadBit();
Window = nbr.ReadUInt16();
Checksum = nbr.ReadUInt16();
UrgentPointer = nbr.ReadUInt16();
//TODO: test
byte option;
long optionsStart = nbr.BaseStream.Position;
Options = new byte[0][];
while ((option = nbr.ReadByte()) != 0 || nbr.BaseStream.Position > start + DataOffset) // 0 = End list
{
if (option == 1) continue; // 1 = No Option
if (option == 2) // Max Segm size
{
byte length = nbr.ReadByte();
byte[] cur = new byte[length];
for (byte i = 0; i < length; i++)
{
cur[i] = nbr.ReadByte();
}
Array.Resize(ref Options, Options.Length + 1);
Options[Options.Length - 1] = cur;
}
}
long dataLength = DataOffset - optionsStart;
Data = new byte[dataLength];
for (int i = 0; i < dataLength; i++)
{
Data[i] = nbr.ReadByte();
}
}
public UdpHeader(byte[] byIpData, int start, int bytesReceived)
{
NetBinaryReader nbr = new NetBinaryReader(byIpData, start);
SourcePort = nbr.ReadUInt16();
DestinationPort = nbr.ReadUInt16();
ByteCount = nbr.ReadUInt16();
Checksum = nbr.ReadUInt16();
data = new byte[ByteCount - OCTET_COUNT];
Array.Copy(byIpData, start + OCTET_COUNT, data, 0, data.Length);
}
public DnsAnswer(NetBinaryReader nbr)
{
Name = nbr.ReadLblOrPntString();
Type = (QType)nbr.ReadUInt16();
ushort rawClass = nbr.ReadUInt16();
if (rawClass > 65279) rawClass = 0;
else if (rawClass > 4 && rawClass < 252) rawClass = 2;
else if (rawClass > 255 && rawClass < 65280) rawClass = 2;
Class = (DnsClass)rawClass;
TTL = nbr.ReadUInt32();
ByteCount = nbr.ReadUInt16();
HandleRData(nbr);
}
public IcmpHeader(byte[] byIpData, int start, int bytesReceived)
{
NetBinaryReader nbr = new NetBinaryReader(byIpData, start);
byte type = nbr.ReadByte();
if (type == 2 || type == 7) type = 1;
else if (type > 20 && type < 30) type = 20;
else if (type > 41) type = 41;
Type = (MessageType)type;
Code = nbr.ReadByte();
Checksum = nbr.ReadUInt16();
data = new byte[bytesReceived - start - OCTET_COUNT];
Array.Copy(byIpData, start + OCTET_COUNT, data, 0, data.Length);
}
public DnsHeader(byte[] byIpData, int start, int bytesReceived)
{
NetBinaryReader nbr = new NetBinaryReader(byIpData, start);
Indentifier = nbr.ReadUInt16();
QueryOrResponseFlag = nbr.ReadBit();
OperationCode = (OpCode)nbr.ReadNible();
AuthoritativeAnswer = nbr.ReadBit();
Turncation = nbr.ReadBit();
RecursionDesired = nbr.ReadBit();
RecursionAvailable = nbr.ReadBit();
nbr.ReadCustomAmount(3);
ResponseCode = (RCode)nbr.ReadNible();
QuestionCount = nbr.ReadUInt16();
AnswerCount = nbr.ReadUInt16();
AuthorityCount = nbr.ReadUInt16();
AdditionalCount = nbr.ReadUInt16();
data = new byte[bytesReceived - start - OCTET_COUNT];
Array.Copy(byIpData, start + OCTET_COUNT, data, 0, data.Length);
}
private void ReadPadOctets(NetBinaryReader nbr, long startPos)
{
long padding = ByteCount - (nbr.BaseStream.Position - startPos);
nbr.BaseStream.Position += padding;
}