nl80211: add wiphy network namespace support

wiphy_linux.go

@@ -0,0 +1,58 @@
+//go:build linux
+// +build linux
+
+package netlink
+
+import (
+	"fmt"
+
+	"github.com/vishvananda/netlink/nl"
+	"golang.org/x/sys/unix"
+)
+
+// Values from include/uapi/linux/nl80211.h in the Linux kernel source.
+const (
+	nl80211GenlName    = "nl80211"
+	nl80211GenlVersion = 1
+
+	nl80211CmdSetWiphyNetns = 49
+	nl80211AttrWiphy        = 1
+	nl80211AttrNetnsFD      = 219
+)
+
+// WiphySetNsFd moves a wireless PHY to the network namespace specified by fd.
+// All interfaces associated with the wiphy must be down before it can be moved.
+func WiphySetNsFd(wiphy, fd int) error {
+	return pkgHandle.WiphySetNsFd(wiphy, fd)
+}
+
+// WiphySetNsFd moves a wireless PHY to the network namespace specified by fd.
+// All interfaces associated with the wiphy must be down before it can be moved.
+func (h *Handle) WiphySetNsFd(wiphy, fd int) error {
+	if wiphy < 0 {
+		return fmt.Errorf("wiphy index must be non-negative: %d", wiphy)
+	}
+	if fd < 0 {
+		return fmt.Errorf("network namespace fd must be non-negative: %d", fd)
+	}
+
+	family, err := h.GenlFamilyGet(nl80211GenlName)
+	if err != nil {
+		return err
+	}
+
+	req := h.newWiphySetNsFdRequest(int(family.ID), wiphy, fd)
+	_, err = req.Execute(unix.NETLINK_GENERIC, 0)
+	return err
+}
+
+func (h *Handle) newWiphySetNsFdRequest(family, wiphy, fd int) *nl.NetlinkRequest {
+	req := h.newNetlinkRequest(family, unix.NLM_F_ACK)
+	req.AddData(&nl.Genlmsg{
+		Command: nl80211CmdSetWiphyNetns,
+		Version: nl80211GenlVersion,
+	})
+	req.AddData(nl.NewRtAttr(nl80211AttrWiphy, nl.Uint32Attr(uint32(wiphy))))
+	req.AddData(nl.NewRtAttr(nl80211AttrNetnsFD, nl.Uint32Attr(uint32(fd))))
+	return req
+}

wiphy_linux_test.go

@@ -0,0 +1,69 @@
+//go:build linux
+// +build linux
+
+package netlink
+
+import (
+	"testing"
+
+	"github.com/vishvananda/netlink/nl"
+	"golang.org/x/sys/unix"
+)
+
+func TestWiphySetNsFdRejectsNegativeArguments(t *testing.T) {
+	for _, tc := range []struct {
+		name  string
+		wiphy int
+		fd    int
+		want  string
+	}{
+		{name: "negative wiphy", wiphy: -1, fd: 42, want: "wiphy index must be non-negative: -1"},
+		{name: "negative namespace fd", wiphy: 7, fd: -1, want: "network namespace fd must be non-negative: -1"},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			err := (&Handle{}).WiphySetNsFd(tc.wiphy, tc.fd)
+			if err == nil || err.Error() != tc.want {
+				t.Fatalf("unexpected error: got %v, want %q", err, tc.want)
+			}
+		})
+	}
+}
+
+func TestNewWiphySetNsFdRequest(t *testing.T) {
+	const (
+		family = 0x23
+		wiphy  = 7
+		fd     = 42
+	)
+
+	req := (&Handle{}).newWiphySetNsFdRequest(family, wiphy, fd)
+	if req.Type != family {
+		t.Fatalf("unexpected netlink message type: got %d, want %d", req.Type, family)
+	}
+	if want := uint16(unix.NLM_F_REQUEST | unix.NLM_F_ACK); req.Flags != want {
+		t.Fatalf("unexpected netlink flags: got %#x, want %#x", req.Flags, want)
+	}
+
+	data := req.Serialize()[unix.SizeofNlMsghdr:]
+	genl := nl.DeserializeGenlmsg(data)
+	if genl.Command != nl80211CmdSetWiphyNetns {
+		t.Fatalf("unexpected generic netlink command: got %d, want %d", genl.Command, nl80211CmdSetWiphyNetns)
+	}
+	if genl.Version != nl80211GenlVersion {
+		t.Fatalf("unexpected generic netlink version: got %d, want %d", genl.Version, nl80211GenlVersion)
+	}
+
+	attrs, err := nl.ParseRouteAttr(data[nl.SizeofGenlmsg:])
+	if err != nil {
+		t.Fatalf("failed to parse attributes: %v", err)
+	}
+	if len(attrs) != 2 {
+		t.Fatalf("unexpected attribute count: got %d, want 2", len(attrs))
+	}
+	if attrs[0].Attr.Type != nl80211AttrWiphy || native.Uint32(attrs[0].Value) != wiphy {
+		t.Fatalf("unexpected wiphy attribute: type=%d value=%d", attrs[0].Attr.Type, native.Uint32(attrs[0].Value))
+	}
+	if attrs[1].Attr.Type != nl80211AttrNetnsFD || native.Uint32(attrs[1].Value) != fd {
+		t.Fatalf("unexpected netns fd attribute: type=%d value=%d", attrs[1].Attr.Type, native.Uint32(attrs[1].Value))
+	}
+}