/// <summary>
/// Gets the key for Ethernet frame.
/// </summary>
/// <param name="frameBytes">Bytes that contains Ethernet frame.</param>
/// <returns><see cref="FlowKey"/> for the provided Ethernet frame.</returns>
public static FlowKey GetKeyForEthernetFrame(byte[] frameBytes)
{
var etherType = EthernetFrame.GetEtherType(frameBytes);
var etherPayload = EthernetFrame.GetPayloadBytes(frameBytes);
Span <Byte> ipPayload = stackalloc byte[0];
var protocol = 0;
Span <Byte> sourceAddress = stackalloc byte[4];
Span <Byte> destinAddress = stackalloc byte[4];
UInt16 sourcePort = 0;
UInt16 destinPort = 0;
switch (etherType)
{
case (ushort)EthernetFrame.EtherTypeEnum.Ipv4:
{
sourceAddress = Ipv4Packet.GetSourceAddress(etherPayload);
destinAddress = Ipv4Packet.GetDestinationAddress(etherPayload);
ipPayload = Ipv4Packet.GetPayloadBytes(etherPayload);
protocol = Ipv4Packet.GetProtocol(etherPayload);
break;
}
case (ushort)EthernetFrame.EtherTypeEnum.Ipv6:
{
sourceAddress = Ipv6Packet.GetSourceAddress(etherPayload);
destinAddress = Ipv6Packet.GetDestinationAddress(etherPayload);
ipPayload = Ipv6Packet.GetPayloadBytes(etherPayload);
protocol = Ipv6Packet.GetProtocol(etherPayload);
break;
}
default:
break;
}
switch (protocol)
{
case 6: // TCP
{
sourcePort = TcpSegment.GetSourcePort(ipPayload);
destinPort = TcpSegment.GetDestinationPort(ipPayload);
break;
}
case 17: // UDP
{
sourcePort = UdpDatagram.GetSourcePort(ipPayload);
destinPort = UdpDatagram.GetDestinationPort(ipPayload);
break;
}
default:
break;
}
// ok we have enough information for creating packet's flow key
return(FlowKey.Create((byte)protocol, sourceAddress, sourcePort, destinAddress, destinPort));
}
