public PacketCapture(ILogger <PacketCapture> logger, NetworkInterface networkInterface, int captureGroup, int thread)
{
_logger = logger;
_networkInterface = networkInterface;
_captureGroup = captureGroup;
_thread = thread;
short protocol = 0x0800; // IP
_socket = new Socket(AddressFamily.Packet, SocketType.Raw, (System.Net.Sockets.ProtocolType)IPAddress.HostToNetworkOrder(protocol));
_socket.Bind(new LLEndPoint(networkInterface));
if (_socket.SetPacketVersion(SocketExtensions.PacketVersions.TPACKET_V3) != 0)
{
_logger.LogError("Unable to set packet version");
}
if (_socket.SetFilter() != 0)
{
_logger.LogError("Unable to set filter");
}
var tp3 = new SocketExtensions.tpacket_req3
{
tp_block_size = 4096,
tp_frame_size = 2048,
tp_block_nr = 16,
tp_frame_nr = 32
};
if (_socket.SetRxRing(tp3) != 0)
{
_logger.LogError("Unable to set RX ring");
}
else
{
var bufferAddress = MMap.Create(
IntPtr.Zero,
tp3.tp_block_size * tp3.tp_block_nr, //4096,//4096 * 4,
MMap.MemoryMappedProtections.PROT_READ | MMap.MemoryMappedProtections.PROT_WRITE,
MMap.MemoryMappedFlags.MAP_SHARED, // | MMap.MemoryMappedFlags.MAP_LOCKED | MMap.MemoryMappedFlags.MAP_NORESERVE,
_socket.Handle,
0);
if (!bufferAddress.HasValue)
{
_logger.LogError("Unable to mmap RX ring");
}
else
{
_ring = new Ring(bufferAddress.Value, tp3);
}
}
if (_socket.SetFanout(_captureGroup) != 0)
{
_logger.LogError("Unable to set fanout");
}
}
public Ring(IntPtr bufferAddress, SocketExtensions.tpacket_req3 tpacket_req3)
{
BufferAddress = bufferAddress;
for (var i = 0; i < tpacket_req3.tp_block_nr; i++)
{
Blocks.Add(new Block(bufferAddress, i, tpacket_req3.tp_block_size));
}
TPacketReq3 = tpacket_req3;
}
