private void AddOption(DHCPv4PacketOption option)
{
_options.Add(option);
if (option is DHCPv4PacketMessageTypeOption option1)
{
MessageType = option1.Value;
}
}
public DHCPv4PacketOption GetOptionByIdentifier(byte optionIdentifier)
{
DHCPv4PacketOption option = _options.FirstOrDefault(x => x.OptionType == optionIdentifier);
if (option == null)
{
return(DHCPv4PacketOption.NotPresented);
}
return(option);
}
public static DHCPv4Packet FromByteArray(Byte[] rawData, IPv4Address source, IPv4Address destionation)
{
try
{
DHCPv4Packet packet = new DHCPv4Packet
{
OpCode = (DHCPv4PacketOperationCodes)rawData[0],
HardwareType = (DHCPv4PacketHardwareAddressTypes)rawData[1],
HardwareAddressLength = rawData[2],
Hops = rawData[3],
TransactionId = ByteHelper.ConvertToUInt32FromByte(rawData, 4),
SecondsElapsed = ByteHelper.ConvertToUInt16FromByte(rawData, 8),
Flags = (DHCPv4PacketFlags)ByteHelper.ConvertToUInt16FromByte(rawData, 10),
ClientIPAdress = IPv4Address.FromByteArray(rawData, 12),
YourIPAdress = IPv4Address.FromByteArray(rawData, 16),
ServerIPAdress = IPv4Address.FromByteArray(rawData, 20),
GatewayIPAdress = IPv4Address.FromByteArray(rawData, 24)
};
packet.Header = new IPv4HeaderInformation(source, destionation);
packet.ClientHardwareAddress = ByteHelper.CopyData(rawData, 28, packet.HardwareAddressLength);
Boolean serverhostnameFound = false;
for (int i = 40; i < 40 + 64; i++)
{
if (rawData[i] != 0)
{
serverhostnameFound = true;
break;
}
}
if (serverhostnameFound == true)
{
packet.ServerHostname = new String(_textEncoding.GetChars(rawData, 40, 64));
}
else
{
packet.ServerHostname = String.Empty;
}
Boolean fileNameFound = false;
for (int i = 104; i < 104 + 128; i++)
{
if (rawData[i] != 0)
{
fileNameFound = true;
break;
}
}
if (fileNameFound == true)
{
packet.FileName = new String(_textEncoding.GetChars(rawData, 104, 128));
}
else
{
packet.FileName = String.Empty;
}
Byte[] actualCookie = new Byte[] { rawData[236], rawData[237], rawData[238], rawData[239] };
if (ByteHelper.AreEqual(_magicCookie, actualCookie) == false)
{
throw new ArgumentException();
}
Int32 index = 240;
while (index < rawData.Length)
{
Byte optionCode = rawData[index];
if (optionCode == 255)
{
break;
}
Byte length = rawData[index + 1];
Byte[] optionData = ByteHelper.CopyData(rawData, index, length + 2);
DHCPv4PacketOption option = DHCPv4PacketOptionFactory.GetOption(optionCode, optionData);
packet.AddOption(option);
index += 2 + length;
}
packet._isValid = true;
packet.SetClientIdentifier();
packet._byteRepresentation = rawData;
return(packet);
}
catch (Exception)
{
return(DHCPv4Packet.Invalid);
}
}