/// <summary>
/// Add UDP header to packet
/// </summary>
/// <param name="packet">Packet structure</param>
/// <param name="destIP">Destination IP</param>
/// <param name="sourcePort">Source port</param>
/// <param name="DestinationPort">Destination port</param>
/// <returns>The pointer to the header</returns>
private static unsafe UDPHeader *addHeader(NetPacketDesc *packet, byte[] destIP, ushort sourcePort, ushort DestinationPort)
{
packet->start -= (short)sizeof(UDPHeader);
UDPHeader *header = (UDPHeader *)(packet->buffer + packet->start);
header->SourcePort = Byte.ReverseBytes(sourcePort);
header->DestinationPort = Byte.ReverseBytes(DestinationPort);
header->Length = Byte.ReverseBytes((ushort)(packet->end - packet->start));
header->Checksum = 0;
return(header);
}
/// <summary>
/// UDP packet handler
/// </summary>
/// <param name="xid">Identification ID</param>
/// <param name="buffer">Buffer pointer</param>
/// <param name="size">Packet size</param>
private static unsafe void handler(byte[] sourceIp, byte *buffer, uint size)
{
UDPHeader *header = (UDPHeader *)buffer;
ushort destPort = Byte.ReverseBytes(header->DestinationPort);
ushort sourcePort = Byte.ReverseBytes(header->SourcePort);
#if UDP_DEBUG_PACKETS
Console.Write("[UDP] Receive from ");
Console.WriteNum(sourcePort);
Console.Write(" to ");
Console.WriteNum(destPort);
Console.WriteLine("");
#endif
m_handlers[destPort]?.Invoke(sourceIp, sourcePort, destPort, buffer + sizeof(UDPHeader), (uint)(Byte.ReverseBytes(header->Length) - sizeof(UDPHeader)));
}
