問題文
An engineer wants to drop unwanted traffic as early as possible, before the kernel has done any of its own processing on the packet. Which hook is intended for that?
選択肢
- The traffic control ingress hook, which runs before the driver has taken the packet off the wire and therefore sees it even earlier than any other hook that the kernel offers for this purpose.
- The socket send hook, which runs when the application writes its data and so sees the bytes before the driver does.
- The XDP hook, which runs at the earliest point in the driver when the packet is received.
- A user-space filter attached with a library, which the kernel consults for each arriving packet before its own processing.