whatcanGOwrong

go/pkg/mod/github.com/cilium/ebpf@v0.11.0/link/netns_test.go

@@ -0,0 +1,68 @@
+package link
+
+import (
+	"os"
+	"testing"
+
+	"github.com/cilium/ebpf"
+	"github.com/cilium/ebpf/asm"
+	"github.com/cilium/ebpf/internal/testutils"
+)
+
+func TestSkLookup(t *testing.T) {
+	testutils.SkipOnOldKernel(t, "5.8", "sk_lookup program")
+
+	prog := mustLoadProgram(t, ebpf.SkLookup, ebpf.AttachSkLookup, "")
+
+	netns, err := os.Open("/proc/self/ns/net")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer netns.Close()
+
+	link, err := AttachNetNs(int(netns.Fd()), prog)
+	if err != nil {
+		t.Fatal("Can't attach link:", err)
+	}
+
+	testLink(t, link, prog)
+}
+
+func createSkLookupProgram() (*ebpf.Program, error) {
+	prog, err := ebpf.NewProgram(&ebpf.ProgramSpec{
+		Type:       ebpf.SkLookup,
+		AttachType: ebpf.AttachSkLookup,
+		License:    "MIT",
+		Instructions: asm.Instructions{
+			asm.Mov.Imm(asm.R0, 0),
+			asm.Return(),
+		},
+	})
+	if err != nil {
+		return nil, err
+	}
+	return prog, nil
+}
+
+func ExampleAttachNetNs() {
+	prog, err := createSkLookupProgram()
+	if err != nil {
+		panic(err)
+	}
+	defer prog.Close()
+
+	// This can be a path to another netns as well.
+	netns, err := os.Open("/proc/self/ns/net")
+	if err != nil {
+		panic(err)
+	}
+	defer netns.Close()
+
+	link, err := AttachNetNs(int(netns.Fd()), prog)
+	if err != nil {
+		panic(err)
+	}
+
+	// The socket lookup program is now active until Close().
+	link.Close()
+}