ebpf_exporter

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package exporter
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/*
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#include <stdlib.h>
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#include <bpf/libbpf.h>
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extern int attachXDPCallback(const struct bpf_program *prog,
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                                   long cookie,
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                                   struct bpf_link **link);
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*/
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import "C"
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import (
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	"fmt"
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	"net"
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	"strings"
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	"syscall"
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	"unsafe"
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	"github.com/aquasecurity/libbpfgo"
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	"golang.org/x/sys/unix"
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)
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var libbpfXDPHandlers []int
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func registerXDPHandler() error {
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	if libbpfXDPHandlers != nil {
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		return nil
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	}
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	name := C.CString("xdp/")
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	defer C.free(unsafe.Pointer(name))
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	opts := C.struct_libbpf_prog_handler_opts{}
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	opts.sz = C.sizeof_struct_libbpf_prog_handler_opts
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	opts.prog_attach_fn = C.libbpf_prog_attach_fn_t(C.attachXDPCallback)
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	handler := C.libbpf_register_prog_handler(name, uint32(libbpfgo.BPFProgTypeXdp), uint32(libbpfgo.BPFAttachTypeXDP), &opts)
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	if handler < 0 {
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		return fmt.Errorf("error registering prog handler: %s", unix.ErrnoName(syscall.Errno(handler)))
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	}
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	libbpfXDPHandlers = append(libbpfXDPHandlers, int(handler))
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	return nil
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}
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func attachXDP(prog *C.struct_bpf_program) ([]*C.struct_bpf_link, error) {
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	name := C.GoString(C.bpf_program__name(prog))
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	section := C.GoString(C.bpf_program__section_name(prog))
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	device := strings.TrimPrefix(section, "xdp/")
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	iface, err := net.InterfaceByName(device)
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	if err != nil {
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		return nil, fmt.Errorf("failed to find device %q for program %q: %v", device, name, err)
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	}
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	link, err := C.bpf_program__attach_xdp(prog, C.int(iface.Index))
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	if link == nil {
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		return nil, fmt.Errorf("failed to attach xdp on device %q for program %s: %v", device, name, err)
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	}
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	return []*C.struct_bpf_link{link}, nil
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}
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