filter, action: Add support for skbedit

Signed-off-by: Zhiyuan Hou <[email protected]>
Noah-Wagner · Dec 17, 2019 · ed89313 · ed89313
1 parent e25c252
commit ed89313
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Showing 4 changed files with 266 additions and 0 deletions.
diff --git a/filter.go b/filter.go
@@ -235,6 +235,30 @@ func NewTunnelKeyAction() *TunnelKeyAction {
 	}
 }
 
+type SkbEditAction struct {
+	ActionAttrs
+	QueueMapping *uint16
+	PType        *uint16
+	Priority     *uint32
+	Mark         *uint32
+}
+
+func (action *SkbEditAction) Type() string {
+	return "skbedit"
+}
+
+func (action *SkbEditAction) Attrs() *ActionAttrs {
+	return &action.ActionAttrs
+}
+
+func NewSkbEditAction() *SkbEditAction {
+	return &SkbEditAction{
+		ActionAttrs: ActionAttrs{
+			Action: TC_ACT_PIPE,
+		},
+	}
+}
+
 // MatchAll filters match all packets
 type MatchAll struct {
 	FilterAttrs

diff --git a/filter_linux.go b/filter_linux.go
@@ -457,6 +457,26 @@ func EncodeActions(attr *nl.RtAttr, actions []Action) error {
 					return fmt.Errorf("invalid dst addr %s for tunnel_key action", action.DstAddr)
 				}
 			}
+		case *SkbEditAction:
+			table := attr.AddRtAttr(tabIndex, nil)
+			tabIndex++
+			table.AddRtAttr(nl.TCA_ACT_KIND, nl.ZeroTerminated("skbedit"))
+			aopts := table.AddRtAttr(nl.TCA_ACT_OPTIONS, nil)
+			skbedit := nl.TcSkbEdit{}
+			toTcGen(action.Attrs(), &skbedit.TcGen)
+			aopts.AddRtAttr(nl.TCA_SKBEDIT_PARMS, skbedit.Serialize())
+			if action.QueueMapping != nil {
+				aopts.AddRtAttr(nl.TCA_SKBEDIT_QUEUE_MAPPING, nl.Uint16Attr(*action.QueueMapping))
+			}
+			if action.Priority != nil {
+				aopts.AddRtAttr(nl.TCA_SKBEDIT_PRIORITY, nl.Uint32Attr(*action.Priority))
+			}
+			if action.PType != nil {
+				aopts.AddRtAttr(nl.TCA_SKBEDIT_PTYPE, nl.Uint16Attr(*action.PType))
+			}
+			if action.Mark != nil {
+				aopts.AddRtAttr(nl.TCA_SKBEDIT_MARK, nl.Uint32Attr(*action.Mark))
+			}
 		case *ConnmarkAction:
 			table := attr.AddRtAttr(tabIndex, nil)
 			tabIndex++
@@ -516,6 +536,8 @@ func parseActions(tables []syscall.NetlinkRouteAttr) ([]Action, error) {
 					action = &GenericAction{}
 				case "tunnel_key":
 					action = &TunnelKeyAction{}
+				case "skbedit":
+					action = &SkbEditAction{}
 				default:
 					break nextattr
 				}
@@ -551,6 +573,25 @@ func parseActions(tables []syscall.NetlinkRouteAttr) ([]Action, error) {
 						case nl.TCA_TUNNEL_KEY_ENC_IPV4_DST:
 							action.(*TunnelKeyAction).DstAddr = net.IP(adatum.Value[:])
 						}
+					case "skbedit":
+						switch adatum.Attr.Type {
+						case nl.TCA_SKBEDIT_PARMS:
+							skbedit := *nl.DeserializeSkbEdit(adatum.Value)
+							action.(*SkbEditAction).ActionAttrs = ActionAttrs{}
+							toAttrs(&skbedit.TcGen, action.Attrs())
+						case nl.TCA_SKBEDIT_MARK:
+							mark := native.Uint32(adatum.Value[0:4])
+							action.(*SkbEditAction).Mark = &mark
+						case nl.TCA_SKBEDIT_PRIORITY:
+							priority := native.Uint32(adatum.Value[0:4])
+							action.(*SkbEditAction).Priority = &priority
+						case nl.TCA_SKBEDIT_PTYPE:
+							ptype := native.Uint16(adatum.Value[0:2])
+							action.(*SkbEditAction).PType = &ptype
+						case nl.TCA_SKBEDIT_QUEUE_MAPPING:
+							mapping := native.Uint16(adatum.Value[0:2])
+							action.(*SkbEditAction).QueueMapping = &mapping
+						}
 					case "bpf":
 						switch adatum.Attr.Type {
 						case nl.TCA_ACT_BPF_PARMS:

diff --git a/filter_test.go b/filter_test.go
@@ -1134,3 +1134,175 @@ func TestFilterU32TunnelKeyAddDel(t *testing.T) {
 		t.Fatal("Failed to remove qdisc")
 	}
 }
+
+func TestFilterU32SkbEditAddDel(t *testing.T) {
+	tearDown := setUpNetlinkTest(t)
+	defer tearDown()
+	if err := LinkAdd(&Ifb{LinkAttrs{Name: "foo"}}); err != nil {
+		t.Fatal(err)
+	}
+	if err := LinkAdd(&Ifb{LinkAttrs{Name: "bar"}}); err != nil {
+		t.Fatal(err)
+	}
+	link, err := LinkByName("foo")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := LinkSetUp(link); err != nil {
+		t.Fatal(err)
+	}
+	redir, err := LinkByName("bar")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := LinkSetUp(redir); err != nil {
+		t.Fatal(err)
+	}
+
+	qdisc := &Ingress{
+		QdiscAttrs: QdiscAttrs{
+			LinkIndex: link.Attrs().Index,
+			Handle:    MakeHandle(0xffff, 0),
+			Parent:    HANDLE_INGRESS,
+		},
+	}
+	if err := QdiscAdd(qdisc); err != nil {
+		t.Fatal(err)
+	}
+	qdiscs, err := SafeQdiscList(link)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	found := false
+	for _, v := range qdiscs {
+		if _, ok := v.(*Ingress); ok {
+			found = true
+			break
+		}
+	}
+	if !found {
+		t.Fatal("Qdisc is the wrong type")
+	}
+
+	skbedit := NewSkbEditAction()
+	ptype := uint16(unix.PACKET_HOST)
+	skbedit.PType = &ptype
+	priority := uint32(0xff)
+	skbedit.Priority = &priority
+	mark := uint32(0xfe)
+	skbedit.Mark = &mark
+	mapping := uint16(0xf)
+	skbedit.QueueMapping = &mapping
+
+	classId := MakeHandle(1, 1)
+	filter := &U32{
+		FilterAttrs: FilterAttrs{
+			LinkIndex: link.Attrs().Index,
+			Parent:    MakeHandle(0xffff, 0),
+			Priority:  1,
+			Protocol:  unix.ETH_P_ALL,
+		},
+		ClassId: classId,
+		Actions: []Action{
+			skbedit,
+			&MirredAction{
+				ActionAttrs: ActionAttrs{
+					Action: TC_ACT_STOLEN,
+				},
+				MirredAction: TCA_EGRESS_REDIR,
+				Ifindex:      redir.Attrs().Index,
+			},
+		},
+	}
+
+	if err := FilterAdd(filter); err != nil {
+		t.Fatal(err)
+	}
+
+	filters, err := FilterList(link, MakeHandle(0xffff, 0))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(filters) != 1 {
+		t.Fatal("Failed to add filter")
+	}
+	u32, ok := filters[0].(*U32)
+	if !ok {
+		t.Fatal("Filter is the wrong type")
+	}
+
+	if len(u32.Actions) != 2 {
+		t.Fatalf("Too few Actions in filter")
+	}
+	if u32.ClassId != classId {
+		t.Fatalf("ClassId of the filter is the wrong value")
+	}
+
+	// actions can be returned in reverse order
+	edit, ok := u32.Actions[0].(*SkbEditAction)
+	if !ok {
+		edit, ok = u32.Actions[1].(*SkbEditAction)
+		if !ok {
+			t.Fatal("Unable to find tunnel action")
+		}
+	}
+
+	if edit.Attrs().Action != TC_ACT_PIPE {
+		t.Fatal("SkbEdit action isn't TC_ACT_PIPE")
+	}
+	if edit.PType == nil || *edit.PType != *skbedit.PType {
+		t.Fatal("Action PType doesn't match")
+	}
+	if edit.QueueMapping == nil || *edit.QueueMapping != *skbedit.QueueMapping {
+		t.Fatal("Action QueueMapping doesn't match")
+	}
+	if edit.Mark == nil || *edit.Mark != *skbedit.Mark {
+		t.Fatal("Action Mark doesn't match")
+	}
+	if edit.Priority == nil || *edit.Priority != *skbedit.Priority {
+		t.Fatal("Action Priority doesn't match")
+	}
+
+	mia, ok := u32.Actions[0].(*MirredAction)
+	if !ok {
+		mia, ok = u32.Actions[1].(*MirredAction)
+		if !ok {
+			t.Fatal("Unable to find mirred action")
+		}
+	}
+
+	if mia.Attrs().Action != TC_ACT_STOLEN {
+		t.Fatal("Mirred action isn't TC_ACT_STOLEN")
+	}
+
+	if err := FilterDel(filter); err != nil {
+		t.Fatal(err)
+	}
+	filters, err = FilterList(link, MakeHandle(0xffff, 0))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(filters) != 0 {
+		t.Fatal("Failed to remove filter")
+	}
+
+	if err := QdiscDel(qdisc); err != nil {
+		t.Fatal(err)
+	}
+	qdiscs, err = SafeQdiscList(link)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	found = false
+	for _, v := range qdiscs {
+		if _, ok := v.(*Ingress); ok {
+			found = true
+			break
+		}
+	}
+	if found {
+		t.Fatal("Failed to remove qdisc")
+	}
+}
diff --git a/nl/tc_linux.go b/nl/tc_linux.go
@@ -92,6 +92,7 @@ const (
 	SizeofTcConnmark     = SizeofTcGen + 0x04
 	SizeofTcMirred       = SizeofTcGen + 0x08
 	SizeofTcTunnelKey    = SizeofTcGen + 0x04
+	SizeofTcSkbEdit      = SizeofTcGen
 	SizeofTcPolice       = 2*SizeofTcRateSpec + 0x20
 )
 
@@ -754,6 +755,34 @@ func (x *TcTunnelKey) Serialize() []byte {
 	return (*(*[SizeofTcTunnelKey]byte)(unsafe.Pointer(x)))[:]
 }
 
+const (
+	TCA_SKBEDIT_UNSPEC = iota
+	TCA_SKBEDIT_TM
+	TCA_SKBEDIT_PARMS
+	TCA_SKBEDIT_PRIORITY
+	TCA_SKBEDIT_QUEUE_MAPPING
+	TCA_SKBEDIT_MARK
+	TCA_SKBEDIT_PAD
+	TCA_SKBEDIT_PTYPE
+	TCA_SKBEDIT_MAX = TCA_SKBEDIT_MARK
+)
+
+type TcSkbEdit struct {
+	TcGen
+}
+
+func (x *TcSkbEdit) Len() int {
+	return SizeofTcSkbEdit
+}
+
+func DeserializeSkbEdit(b []byte) *TcSkbEdit {
+	return (*TcSkbEdit)(unsafe.Pointer(&b[0:SizeofTcSkbEdit][0]))
+}
+
+func (x *TcSkbEdit) Serialize() []byte {
+	return (*(*[SizeofTcSkbEdit]byte)(unsafe.Pointer(x)))[:]
+}
+
 // struct tc_police {
 // 	__u32			index;
 // 	int			action;