I have been trying to solve these 2 problems, but without success.
I wonder if it's possible to remove specific packets from an interface with Gopacket or is it just for listening on the wire? For example when I send a UDP packet to a wrong port and then with Gopacket I correct it, it will send 2 packets, 1 to the wrong port and 1 to the correct one. Is there a way to discard/drop the wrong packet with Gopacket?
What I am trying to do, is to pick up all packets that are sent by a client over IP and then encapsulate each packet as a payload in another protocol X and send to the remote host which will receive on protocol X, get the payload and send it on its interface to reach the server over IP again. (IP (Client) -> Protocol X (Sniffer 1) -> Protocol X (Sniffer 2) -> IP (Server))
I have verified that the packet which Sniffer 1 picks up from the Client's interface is the same which arrives at Sniffer 2, but the problem is when Sniffer 2 injects it on the Server's interface. I can't see that packet with tcpdump or any other tool. The packet is injected with this command:
if handle, err := pcap.OpenLive("enp0s8", 1600, true, 100); err != nil {
panic(err)
} else {
err = handle.WritePacketData(packet.Data())
}
If the Protocol X part is avoided, then the server will receive messages from client, but with Protocol X it is not possible.
Thanks in advance!