package link
import (
"fmt"
"github.com/cilium/ebpf"
)
// XDPAttachFlags represents how XDP program will be attached to interface.
type XDPAttachFlags uint32
const (
// XDPGenericMode (SKB) links XDP BPF program for drivers which do
// not yet support native XDP.
XDPGenericMode XDPAttachFlags = 1 << (iota + 1)
// XDPDriverMode links XDP BPF program into the driver’s receive path.
XDPDriverMode
// XDPOffloadMode offloads the entire XDP BPF program into hardware.
XDPOffloadMode
)
type XDPOptions struct {
// Program must be an XDP BPF program.
Program *ebpf.Program
// Interface is the interface index to attach program to.
Interface int
// Flags is one of XDPAttachFlags (optional).
//
// Only one XDP mode should be set, without flag defaults
// to driver/generic mode (best effort).
Flags XDPAttachFlags
}
// AttachXDP links an XDP BPF program to an XDP hook.
func AttachXDP(opts XDPOptions) (Link, error) {
if t := opts.Program.Type(); t != ebpf.XDP {
return nil, fmt.Errorf("invalid program type %s, expected XDP", t)
}
if opts.Interface < 1 {
return nil, fmt.Errorf("invalid interface index: %d", opts.Interface)
}
rawLink, err := AttachRawLink(RawLinkOptions{
Program: opts.Program,
Attach: ebpf.AttachXDP,
Target: opts.Interface,
Flags: uint32(opts.Flags),
})
return rawLink, err
}