refactor nftable Object handling (NamedObj type) (#259)

* Refactored obj.go to a more generic approach
* Added object support for already implemented expressions
* Added test for limit object

fixes https://github.com/google/nftables/issues/253
This commit is contained in:
turekt 2024-07-29 08:43:58 +02:00 committed by GitHub
parent 912dee68b1
commit 3b928008ad
No known key found for this signature in database
GPG Key ID: B5690EEEBB952194
5 changed files with 715 additions and 129 deletions

View File

@ -15,12 +15,11 @@
package nftables
import (
"github.com/google/nftables/binaryutil"
"github.com/google/nftables/expr"
"github.com/mdlayher/netlink"
"golang.org/x/sys/unix"
)
// CounterObj implements Obj.
type CounterObj struct {
Table *Table
Name string // e.g. “fwded”
@ -41,6 +40,20 @@ func (c *CounterObj) unmarshal(ad *netlink.AttributeDecoder) error {
return ad.Err()
}
func (c *CounterObj) data() expr.Any {
return &expr.Counter{
Bytes: c.Bytes,
Packets: c.Packets,
}
}
func (c *CounterObj) name() string {
return c.Name
}
func (c *CounterObj) objType() ObjType {
return ObjTypeCounter
}
func (c *CounterObj) table() *Table {
return c.Table
}
@ -48,22 +61,3 @@ func (c *CounterObj) table() *Table {
func (c *CounterObj) family() TableFamily {
return c.Table.Family
}
func (c *CounterObj) marshal(data bool) ([]byte, error) {
obj, err := netlink.MarshalAttributes([]netlink.Attribute{
{Type: unix.NFTA_COUNTER_BYTES, Data: binaryutil.BigEndian.PutUint64(c.Bytes)},
{Type: unix.NFTA_COUNTER_PACKETS, Data: binaryutil.BigEndian.PutUint64(c.Packets)},
})
if err != nil {
return nil, err
}
attrs := []netlink.Attribute{
{Type: unix.NFTA_OBJ_TABLE, Data: []byte(c.Table.Name + "\x00")},
{Type: unix.NFTA_OBJ_NAME, Data: []byte(c.Name + "\x00")},
{Type: unix.NFTA_OBJ_TYPE, Data: binaryutil.BigEndian.PutUint32(unix.NFT_OBJECT_COUNTER)},
}
if data {
attrs = append(attrs, netlink.Attribute{Type: unix.NLA_F_NESTED | unix.NFTA_OBJ_DATA, Data: obj})
}
return netlink.MarshalAttributes(attrs)
}

View File

@ -259,7 +259,7 @@ func (monitor *Monitor) monitor() {
}
monitor.eventCh <- event
case unix.NFT_MSG_NEWOBJ, unix.NFT_MSG_DELOBJ:
obj, err := objFromMsg(msg)
obj, err := objFromMsg(msg, true)
event := &MonitorEvent{
Type: MonitorEventType(msgType),
Data: obj,

View File

@ -1783,7 +1783,7 @@ func TestListChainByName(t *testing.T) {
}
func TestListChainByNameUsingLasting(t *testing.T) {
conn, newNS := nftest.OpenSystemConn(t, *enableSysTests)
_, newNS := nftest.OpenSystemConn(t, *enableSysTests)
conn, err := nftables.New(nftables.WithNetNSFd(int(newNS)), nftables.AsLasting())
if err != nil {
t.Fatalf("nftables.New() failed: %v", err)
@ -1882,8 +1882,7 @@ func TestListTableByName(t *testing.T) {
}
// not specifying correct family should return err since no table in ipv4
tr, err = conn.ListTable(table2.Name)
if err == nil {
if _, err = conn.ListTable(table2.Name); err == nil {
t.Fatalf("conn.ListTable() should have failed")
}
@ -2106,17 +2105,18 @@ func TestGetObjReset(t *testing.T) {
}
filter := &nftables.Table{Name: "filter", Family: nftables.TableFamilyIPv4}
obj, err := c.ResetObject(&nftables.CounterObj{
obj, err := c.ResetObject(&nftables.NamedObj{
Table: filter,
Name: "fwded",
Type: nftables.ObjTypeCounter,
})
if err != nil {
t.Fatal(err)
}
co, ok := obj.(*nftables.CounterObj)
co, ok := obj.(*nftables.NamedObj)
if !ok {
t.Fatalf("unexpected type: got %T, want *nftables.CounterObj", obj)
t.Fatalf("unexpected type: got %T, want *nftables.ObjAttr", obj)
}
if got, want := co.Table.Name, filter.Name; got != want {
t.Errorf("unexpected table name: got %q, want %q", got, want)
@ -2124,10 +2124,14 @@ func TestGetObjReset(t *testing.T) {
if got, want := co.Table.Family, filter.Family; got != want {
t.Errorf("unexpected table family: got %d, want %d", got, want)
}
if got, want := co.Packets, uint64(9); got != want {
o, ok := co.Obj.(*expr.Counter)
if !ok {
t.Fatalf("unexpected type: got %T, want *expr.Counter", o)
}
if got, want := o.Packets, uint64(9); got != want {
t.Errorf("unexpected number of packets: got %d, want %d", got, want)
}
if got, want := co.Bytes, uint64(1121); got != want {
if got, want := o.Bytes, uint64(1121); got != want {
t.Errorf("unexpected number of bytes: got %d, want %d", got, want)
}
}
@ -2164,6 +2168,366 @@ func TestObjAPI(t *testing.T) {
Priority: nftables.ChainPriorityFilter,
})
counter1 := c.AddObj(&nftables.NamedObj{
Table: table,
Name: "fwded1",
Type: nftables.ObjTypeCounter,
Obj: &expr.Counter{
Bytes: 1,
Packets: 1,
},
})
counter2 := c.AddObj(&nftables.NamedObj{
Table: table,
Name: "fwded2",
Type: nftables.ObjTypeCounter,
Obj: &expr.Counter{
Bytes: 1,
Packets: 1,
},
})
c.AddObj(&nftables.NamedObj{
Table: tableOther,
Name: "fwdedOther",
Type: nftables.ObjTypeCounter,
Obj: &expr.Counter{
Bytes: 0,
Packets: 0,
},
})
c.AddRule(&nftables.Rule{
Table: table,
Chain: chain,
Exprs: []expr.Any{
&expr.Objref{
Type: 1,
Name: "fwded1",
},
},
})
if err := c.Flush(); err != nil {
t.Fatalf(err.Error())
}
objs, err := c.GetObjects(table)
if err != nil {
t.Errorf("c.GetObjects(table) failed: %v failed", err)
}
if got := len(objs); got != 2 {
t.Fatalf("unexpected number of objects: got %d, want %d", got, 2)
}
objsOther, err := c.GetObjects(tableOther)
if err != nil {
t.Errorf("c.GetObjects(tableOther) failed: %v failed", err)
}
if got := len(objsOther); got != 1 {
t.Fatalf("unexpected number of objects: got %d, want %d", got, 1)
}
obj1, err := c.GetObject(counter1)
if err != nil {
t.Errorf("c.GetObject(counter1) failed: %v failed", err)
}
rcounter1, ok := obj1.(*nftables.NamedObj)
if !ok {
t.Fatalf("unexpected type: got %T, want *nftables.ObjAttr", obj1)
}
if rcounter1.Name != "fwded1" {
t.Fatalf("unexpected counter name: got %s, want %s", rcounter1.Name, "fwded1")
}
obj2, err := c.GetObject(counter2)
if err != nil {
t.Errorf("c.GetObject(counter2) failed: %v failed", err)
}
rcounter2, ok := obj2.(*nftables.NamedObj)
if !ok {
t.Fatalf("unexpected type: got %T, want *nftables.CounterObj", obj2)
}
if rcounter2.Name != "fwded2" {
t.Fatalf("unexpected counter name: got %s, want %s", rcounter2.Name, "fwded2")
}
_, err = c.ResetObject(counter1)
if err != nil {
t.Errorf("c.ResetObjects(table) failed: %v failed", err)
}
obj1, err = c.GetObject(counter1)
if err != nil {
t.Errorf("c.GetObject(counter1) failed: %v failed", err)
}
if counter1 := obj1.(*nftables.NamedObj).Obj.(*expr.Counter); counter1.Packets > 0 {
t.Errorf("unexpected packets number: got %d, want %d", counter1.Packets, 0)
}
obj2, err = c.GetObject(counter2)
if err != nil {
t.Errorf("c.GetObject(counter2) failed: %v failed", err)
}
if counter2 := obj2.(*nftables.NamedObj).Obj.(*expr.Counter); counter2.Packets != 1 {
t.Errorf("unexpected packets number: got %d, want %d", counter2.Packets, 1)
}
legacy, err := c.GetObj(counter1)
if err != nil {
t.Errorf("c.GetObj(counter1) failed: %v failed", err)
}
if len(legacy) != 2 {
t.Errorf("unexpected number of objects: got %d, want %d", len(legacy), 2)
}
legacyReset, err := c.GetObjReset(counter1)
if err != nil {
t.Errorf("c.GetObjReset(counter1) failed: %v failed", err)
}
if len(legacyReset) != 2 {
t.Errorf("unexpected number of objects: got %d, want %d", len(legacyReset), 2)
}
}
func TestDeleteLegacyQuotaObj(t *testing.T) {
conn, newNS := nftest.OpenSystemConn(t, *enableSysTests)
defer nftest.CleanupSystemConn(t, newNS)
conn.FlushRuleset()
defer conn.FlushRuleset()
table := &nftables.Table{
Name: "quota_demo",
Family: nftables.TableFamilyIPv4,
}
tr := conn.AddTable(table)
c := &nftables.Chain{
Name: "filter",
Table: table,
}
conn.AddChain(c)
o := &nftables.QuotaObj{
Table: tr,
Name: "q_test",
Bytes: 0x06400000,
Consumed: 0,
Over: true,
}
conn.AddObj(o)
if err := conn.Flush(); err != nil {
t.Fatalf("conn.Flush() failed: %v", err)
}
obj, err := conn.GetObj(&nftables.QuotaObj{
Table: table,
Name: "q_test",
})
if err != nil {
t.Fatalf("conn.GetObj() failed: %v", err)
}
if got, want := len(obj), 1; got != want {
t.Fatalf("unexpected number of objects: got %d, want %d", got, want)
}
if got, want := obj[0], o; !reflect.DeepEqual(got, want) {
t.Errorf("got = %+v, want = %+v", got, want)
}
conn.DeleteObject(&nftables.QuotaObj{
Table: tr,
Name: "q_test",
})
if err := conn.Flush(); err != nil {
t.Fatalf("conn.Flush() failed: %v", err)
}
obj, err = conn.GetObj(&nftables.QuotaObj{
Table: table,
Name: "q_test",
})
if err != nil {
t.Fatalf("conn.GetObj() failed: %v", err)
}
if got, want := len(obj), 0; got != want {
t.Fatalf("unexpected object list length: got %d, want %d", got, want)
}
}
func TestAddLegacyQuotaObj(t *testing.T) {
conn, newNS := nftest.OpenSystemConn(t, *enableSysTests)
defer nftest.CleanupSystemConn(t, newNS)
conn.FlushRuleset()
defer conn.FlushRuleset()
table := &nftables.Table{
Name: "quota_demo",
Family: nftables.TableFamilyIPv4,
}
tr := conn.AddTable(table)
c := &nftables.Chain{
Name: "filter",
Table: table,
}
conn.AddChain(c)
o := &nftables.QuotaObj{
Table: tr,
Name: "q_test",
Bytes: 0x06400000,
Consumed: 0,
Over: true,
}
conn.AddObj(o)
if err := conn.Flush(); err != nil {
t.Errorf("conn.Flush() failed: %v", err)
}
obj, err := conn.GetObj(&nftables.QuotaObj{
Table: table,
Name: "q_test",
})
if err != nil {
t.Fatalf("conn.GetObj() failed: %v", err)
}
if got, want := len(obj), 1; got != want {
t.Fatalf("unexpected object list length: got %d, want %d", got, want)
}
o1, ok := obj[0].(*nftables.QuotaObj)
if !ok {
t.Fatalf("unexpected type: got %T, want *QuotaObj", obj[0])
}
if got, want := o1.Name, o.Name; got != want {
t.Fatalf("quota name mismatch: got %s, want %s", got, want)
}
if got, want := o1.Bytes, o.Bytes; got != want {
t.Fatalf("quota bytes mismatch: got %d, want %d", got, want)
}
if got, want := o1.Consumed, o.Consumed; got != want {
t.Fatalf("quota consumed mismatch: got %d, want %d", got, want)
}
if got, want := o1.Over, o.Over; got != want {
t.Fatalf("quota over mismatch: got %v, want %v", got, want)
}
}
func TestAddLegacyQuotaObjRef(t *testing.T) {
conn, newNS := nftest.OpenSystemConn(t, *enableSysTests)
defer nftest.CleanupSystemConn(t, newNS)
conn.FlushRuleset()
defer conn.FlushRuleset()
table := &nftables.Table{
Name: "quota_demo",
Family: nftables.TableFamilyIPv4,
}
tr := conn.AddTable(table)
c := &nftables.Chain{
Name: "filter",
Table: table,
}
conn.AddChain(c)
o := &nftables.QuotaObj{
Table: tr,
Name: "q_test",
Bytes: 0x06400000,
Consumed: 0,
Over: true,
}
conn.AddObj(o)
r := &nftables.Rule{
Table: table,
Chain: c,
Exprs: []expr.Any{
&expr.Objref{
Type: 2,
Name: "q_test",
},
},
}
conn.AddRule(r)
if err := conn.Flush(); err != nil {
t.Fatalf("failed to flush: %v", err)
}
rules, err := conn.GetRules(table, c)
if err != nil {
t.Fatalf("failed to get rules: %v", err)
}
if got, want := len(rules), 1; got != want {
t.Fatalf("unexpected number of rules: got %d, want %d", got, want)
}
if got, want := len(rules[0].Exprs), 1; got != want {
t.Fatalf("unexpected number of exprs: got %d, want %d", got, want)
}
objref, ok := rules[0].Exprs[0].(*expr.Objref)
if !ok {
t.Fatalf("Exprs[0] is type %T, want *expr.Objref", rules[0].Exprs[0])
}
if want := r.Exprs[0]; !reflect.DeepEqual(objref, want) {
t.Errorf("objref expr = %+v, wanted %+v", objref, want)
}
}
func TestObjAPICounterLegacyType(t *testing.T) {
if os.Getenv("TRAVIS") == "true" {
t.SkipNow()
}
// Create a new network namespace to test these operations,
// and tear down the namespace at test completion.
c, newNS := nftest.OpenSystemConn(t, *enableSysTests)
defer nftest.CleanupSystemConn(t, newNS)
// Clear all rules at the beginning + end of the test.
c.FlushRuleset()
defer c.FlushRuleset()
table := c.AddTable(&nftables.Table{
Family: nftables.TableFamilyIPv4,
Name: "filter",
})
tableOther := c.AddTable(&nftables.Table{
Family: nftables.TableFamilyIPv4,
Name: "foo",
})
chain := c.AddChain(&nftables.Chain{
Name: "chain",
Table: table,
Type: nftables.ChainTypeFilter,
Hooknum: nftables.ChainHookPostrouting,
Priority: nftables.ChainPriorityFilter,
})
counter1 := c.AddObj(&nftables.CounterObj{
Table: table,
Name: "fwded1",
@ -2767,7 +3131,7 @@ func TestCreateUseAnonymousSet(t *testing.T) {
}
func TestCappedErrMsgOnSets(t *testing.T) {
c, newNS := nftest.OpenSystemConn(t, *enableSysTests)
_, newNS := nftest.OpenSystemConn(t, *enableSysTests)
c, err := nftables.New(nftables.WithNetNSFd(int(newNS)), nftables.AsLasting())
if err != nil {
t.Fatalf("nftables.New() failed: %v", err)
@ -6285,6 +6649,84 @@ func TestGetRulesObjref(t *testing.T) {
}
}
func TestAddLimitObj(t *testing.T) {
conn, newNS := nftest.OpenSystemConn(t, *enableSysTests)
defer nftest.CleanupSystemConn(t, newNS)
conn.FlushRuleset()
defer conn.FlushRuleset()
table := &nftables.Table{
Name: "limit_demo",
Family: nftables.TableFamilyIPv4,
}
tr := conn.AddTable(table)
c := &nftables.Chain{
Name: "filter",
Table: table,
}
conn.AddChain(c)
l := &expr.Limit{
Type: expr.LimitTypePkts,
Rate: 400,
Unit: expr.LimitTimeMinute,
Burst: 5,
Over: false,
}
o := &nftables.NamedObj{
Table: tr,
Name: "limit_test",
Type: nftables.ObjTypeLimit,
Obj: l,
}
conn.AddObj(o)
if err := conn.Flush(); err != nil {
t.Errorf("conn.Flush() failed: %v", err)
}
obj, err := conn.GetObj(&nftables.NamedObj{
Table: table,
Name: "limit_test",
Type: nftables.ObjTypeLimit,
})
if err != nil {
t.Fatalf("conn.GetObj() failed: %v", err)
}
if got, want := len(obj), 1; got != want {
t.Fatalf("unexpected object list length: got %d, want %d", got, want)
}
o1, ok := obj[0].(*nftables.NamedObj)
if !ok {
t.Fatalf("unexpected type: got %T, want *ObjAttr", obj[0])
}
if got, want := o1.Name, o.Name; got != want {
t.Fatalf("limit name mismatch: got %s, want %s", got, want)
}
q, ok := o1.Obj.(*expr.Limit)
if !ok {
t.Fatalf("unexpected type: got %T, want *expr.Quota", o1.Obj)
}
if got, want := q.Burst, l.Burst; got != want {
t.Fatalf("limit burst mismatch: got %d, want %d", got, want)
}
if got, want := q.Unit, l.Unit; got != want {
t.Fatalf("limit unit mismatch: got %d, want %d", got, want)
}
if got, want := q.Rate, l.Rate; got != want {
t.Fatalf("limit rate mismatch: got %v, want %v", got, want)
}
if got, want := q.Over, l.Over; got != want {
t.Fatalf("limit over mismatch: got %v, want %v", got, want)
}
if got, want := q.Type, l.Type; got != want {
t.Fatalf("limit type mismatch: got %v, want %v", got, want)
}
}
func TestAddQuotaObj(t *testing.T) {
conn, newNS := nftest.OpenSystemConn(t, *enableSysTests)
defer nftest.CleanupSystemConn(t, newNS)
@ -6303,22 +6745,26 @@ func TestAddQuotaObj(t *testing.T) {
}
conn.AddChain(c)
o := &nftables.QuotaObj{
Table: tr,
Name: "q_test",
Bytes: 0x06400000,
Consumed: 0,
Over: true,
o := &nftables.NamedObj{
Table: tr,
Name: "q_test",
Type: nftables.ObjTypeQuota,
Obj: &expr.Quota{
Bytes: 0x06400000,
Consumed: 0,
Over: true,
},
}
conn.AddObj(o)
if err := conn.Flush(); err != nil {
t.Errorf("conn.Flush() failed: %v", err)
t.Fatalf("conn.Flush() failed: %v", err)
}
obj, err := conn.GetObj(&nftables.QuotaObj{
obj, err := conn.GetObj(&nftables.NamedObj{
Table: table,
Name: "q_test",
Type: nftables.ObjTypeQuota,
})
if err != nil {
t.Fatalf("conn.GetObj() failed: %v", err)
@ -6328,20 +6774,25 @@ func TestAddQuotaObj(t *testing.T) {
t.Fatalf("unexpected object list length: got %d, want %d", got, want)
}
o1, ok := obj[0].(*nftables.QuotaObj)
o1, ok := obj[0].(*nftables.NamedObj)
if !ok {
t.Fatalf("unexpected type: got %T, want *QuotaObj", obj[0])
t.Fatalf("unexpected type: got %T, want *ObjAttr", obj[0])
}
if got, want := o1.Name, o.Name; got != want {
t.Fatalf("quota name mismatch: got %s, want %s", got, want)
}
if got, want := o1.Bytes, o.Bytes; got != want {
q, ok := o1.Obj.(*expr.Quota)
if !ok {
t.Fatalf("unexpected type: got %T, want *expr.Quota", o1.Obj)
}
o2, _ := o.Obj.(*expr.Quota)
if got, want := q.Bytes, o2.Bytes; got != want {
t.Fatalf("quota bytes mismatch: got %d, want %d", got, want)
}
if got, want := o1.Consumed, o.Consumed; got != want {
if got, want := q.Consumed, o2.Consumed; got != want {
t.Fatalf("quota consumed mismatch: got %d, want %d", got, want)
}
if got, want := o1.Over, o.Over; got != want {
if got, want := q.Over, o2.Over; got != want {
t.Fatalf("quota over mismatch: got %v, want %v", got, want)
}
}
@ -6409,7 +6860,7 @@ func TestAddQuotaObjRef(t *testing.T) {
}
}
func TestDeleteQuotaObj(t *testing.T) {
func TestDeleteQuotaObjMixedTypes(t *testing.T) {
conn, newNS := nftest.OpenSystemConn(t, *enableSysTests)
defer nftest.CleanupSystemConn(t, newNS)
conn.FlushRuleset()
@ -6427,12 +6878,15 @@ func TestDeleteQuotaObj(t *testing.T) {
}
conn.AddChain(c)
o := &nftables.QuotaObj{
Table: tr,
Name: "q_test",
Bytes: 0x06400000,
Consumed: 0,
Over: true,
o := &nftables.NamedObj{
Table: tr,
Name: "q_test",
Type: nftables.ObjTypeQuota,
Obj: &expr.Quota{
Bytes: 0x06400000,
Consumed: 0,
Over: true,
},
}
conn.AddObj(o)
@ -6440,9 +6894,10 @@ func TestDeleteQuotaObj(t *testing.T) {
t.Fatalf("conn.Flush() failed: %v", err)
}
obj, err := conn.GetObj(&nftables.QuotaObj{
Table: table,
obj, err := conn.GetObj(&nftables.NamedObj{
Table: tr,
Name: "q_test",
Type: nftables.ObjTypeQuota,
})
if err != nil {
t.Fatalf("conn.GetObj() failed: %v", err)
@ -6452,7 +6907,18 @@ func TestDeleteQuotaObj(t *testing.T) {
t.Fatalf("unexpected number of objects: got %d, want %d", got, want)
}
if got, want := obj[0], o; !reflect.DeepEqual(got, want) {
o2, _ := o.Obj.(*expr.Quota)
want := &nftables.NamedObj{
Table: tr,
Name: "q_test",
Type: nftables.ObjTypeQuota,
Obj: &expr.Quota{
Bytes: o2.Bytes,
Consumed: o2.Consumed,
Over: o2.Over,
},
}
if got, want := obj[0], want; !reflect.DeepEqual(got, want) {
t.Errorf("got = %+v, want = %+v", got, want)
}

229
obj.go
View File

@ -18,6 +18,9 @@ import (
"encoding/binary"
"fmt"
"github.com/google/nftables/binaryutil"
"github.com/google/nftables/expr"
"github.com/google/nftables/internal/parseexprfunc"
"github.com/mdlayher/netlink"
"golang.org/x/sys/unix"
)
@ -27,13 +30,73 @@ var (
delObjHeaderType = netlink.HeaderType((unix.NFNL_SUBSYS_NFTABLES << 8) | unix.NFT_MSG_DELOBJ)
)
type ObjType uint32
// https://git.netfilter.org/libnftnl/tree/include/linux/netfilter/nf_tables.h?id=be0bae0ad31b0adb506f96de083f52a2bd0d4fbf#n1612
const (
ObjTypeCounter ObjType = unix.NFT_OBJECT_COUNTER
ObjTypeQuota ObjType = unix.NFT_OBJECT_QUOTA
ObjTypeCtHelper ObjType = unix.NFT_OBJECT_CT_HELPER
ObjTypeLimit ObjType = unix.NFT_OBJECT_LIMIT
ObjTypeConnLimit ObjType = unix.NFT_OBJECT_CONNLIMIT
ObjTypeTunnel ObjType = unix.NFT_OBJECT_TUNNEL
ObjTypeCtTimeout ObjType = unix.NFT_OBJECT_CT_TIMEOUT
ObjTypeSecMark ObjType = unix.NFT_OBJECT_SECMARK
ObjTypeCtExpect ObjType = unix.NFT_OBJECT_CT_EXPECT
ObjTypeSynProxy ObjType = unix.NFT_OBJECT_SYNPROXY
)
var objByObjTypeMagic = map[ObjType]string{
ObjTypeCounter: "counter",
ObjTypeQuota: "quota",
ObjTypeLimit: "limit",
ObjTypeConnLimit: "connlimit",
ObjTypeCtHelper: "cthelper", // not implemented in expr
ObjTypeTunnel: "tunnel", // not implemented in expr
ObjTypeCtTimeout: "cttimeout", // not implemented in expr
ObjTypeSecMark: "secmark", // not implemented in expr
ObjTypeCtExpect: "ctexpect", // not implemented in expr
ObjTypeSynProxy: "synproxy", // not implemented in expr
}
// Obj represents a netfilter stateful object. See also
// https://wiki.nftables.org/wiki-nftables/index.php/Stateful_objects
type Obj interface {
table() *Table
family() TableFamily
unmarshal(*netlink.AttributeDecoder) error
marshal(data bool) ([]byte, error)
data() expr.Any
name() string
objType() ObjType
}
// NamedObj represents nftables stateful object attributes
// Corresponds to netfilter nft_object_attributes as per
// https://git.netfilter.org/libnftnl/tree/include/linux/netfilter/nf_tables.h?id=116e95aa7b6358c917de8c69f6f173874030b46b#n1626
type NamedObj struct {
Table *Table
Name string
Type ObjType
Obj expr.Any
}
func (o *NamedObj) table() *Table {
return o.Table
}
func (o *NamedObj) family() TableFamily {
return o.Table.Family
}
func (o *NamedObj) data() expr.Any {
return o.Obj
}
func (o *NamedObj) name() string {
return o.Name
}
func (o *NamedObj) objType() ObjType {
return o.Type
}
// AddObject adds the specified Obj. Alias of AddObj.
@ -46,18 +109,27 @@ func (cc *Conn) AddObject(o Obj) Obj {
func (cc *Conn) AddObj(o Obj) Obj {
cc.mu.Lock()
defer cc.mu.Unlock()
data, err := o.marshal(true)
data, err := expr.MarshalExprData(byte(o.family()), o.data())
if err != nil {
cc.setErr(err)
return nil
}
attrs := []netlink.Attribute{
{Type: unix.NFTA_OBJ_TABLE, Data: []byte(o.table().Name + "\x00")},
{Type: unix.NFTA_OBJ_NAME, Data: []byte(o.name() + "\x00")},
{Type: unix.NFTA_OBJ_TYPE, Data: binaryutil.BigEndian.PutUint32(uint32(o.objType()))},
}
if len(data) > 0 {
attrs = append(attrs, netlink.Attribute{Type: unix.NLA_F_NESTED | unix.NFTA_OBJ_DATA, Data: data})
}
cc.messages = append(cc.messages, netlink.Message{
Header: netlink.Header{
Type: netlink.HeaderType((unix.NFNL_SUBSYS_NFTABLES << 8) | unix.NFT_MSG_NEWOBJ),
Flags: netlink.Request | netlink.Acknowledge | netlink.Create,
},
Data: append(extraHeader(uint8(o.family()), 0), data...),
Data: append(extraHeader(uint8(o.family()), 0), cc.marshalAttr(attrs)...),
})
return o
}
@ -66,12 +138,12 @@ func (cc *Conn) AddObj(o Obj) Obj {
func (cc *Conn) DeleteObject(o Obj) {
cc.mu.Lock()
defer cc.mu.Unlock()
data, err := o.marshal(false)
if err != nil {
cc.setErr(err)
return
attrs := []netlink.Attribute{
{Type: unix.NFTA_OBJ_TABLE, Data: []byte(o.table().Name + "\x00")},
{Type: unix.NFTA_OBJ_NAME, Data: []byte(o.name() + "\x00")},
{Type: unix.NFTA_OBJ_TYPE, Data: binaryutil.BigEndian.PutUint32(uint32(o.objType()))},
}
data := cc.marshalAttr(attrs)
data = append(data, cc.marshalAttr([]netlink.Attribute{{Type: unix.NLA_F_NESTED | unix.NFTA_OBJ_DATA}})...)
cc.messages = append(cc.messages, netlink.Message{
@ -85,17 +157,26 @@ func (cc *Conn) DeleteObject(o Obj) {
// GetObj is a legacy method that return all Obj that belongs
// to the same table as the given one
// This function returns the same concrete type as passed,
// e.g. QuotaObj, CounterObj or NamedObj. Prefer using the more
// generic NamedObj over the legacy QuotaObj and CounterObj types.
func (cc *Conn) GetObj(o Obj) ([]Obj, error) {
return cc.getObj(nil, o.table(), unix.NFT_MSG_GETOBJ)
return cc.getObjWithLegacyType(nil, o.table(), unix.NFT_MSG_GETOBJ, cc.useLegacyObjType(o))
}
// GetObjReset is a legacy method that reset all Obj that belongs
// the same table as the given one
// This function returns the same concrete type as passed,
// e.g. QuotaObj, CounterObj or NamedObj. Prefer using the more
// generic NamedObj over the legacy QuotaObj and CounterObj types.
func (cc *Conn) GetObjReset(o Obj) ([]Obj, error) {
return cc.getObj(nil, o.table(), unix.NFT_MSG_GETOBJ_RESET)
return cc.getObjWithLegacyType(nil, o.table(), unix.NFT_MSG_GETOBJ_RESET, cc.useLegacyObjType(o))
}
// GetObject gets the specified Object
// This function returns the same concrete type as passed,
// e.g. QuotaObj, CounterObj or NamedObj. Prefer using the more
// generic NamedObj over the legacy QuotaObj and CounterObj types.
func (cc *Conn) GetObject(o Obj) (Obj, error) {
objs, err := cc.getObj(o, o.table(), unix.NFT_MSG_GETOBJ)
@ -107,11 +188,16 @@ func (cc *Conn) GetObject(o Obj) (Obj, error) {
}
// GetObjects get all the Obj that belongs to the given table
// This function will always return legacy QuotaObj/CounterObj
// types for backwards compatibility
func (cc *Conn) GetObjects(t *Table) ([]Obj, error) {
return cc.getObj(nil, t, unix.NFT_MSG_GETOBJ)
}
// ResetObject reset the given Obj
// This function returns the same concrete type as passed,
// e.g. QuotaObj, CounterObj or NamedObj. Prefer using the more
// generic NamedObj over the legacy QuotaObj and CounterObj types.
func (cc *Conn) ResetObject(o Obj) (Obj, error) {
objs, err := cc.getObj(o, o.table(), unix.NFT_MSG_GETOBJ_RESET)
@ -123,11 +209,13 @@ func (cc *Conn) ResetObject(o Obj) (Obj, error) {
}
// ResetObjects reset all the Obj that belongs to the given table
// This function will always return legacy QuotaObj/CounterObj
// types for backwards compatibility
func (cc *Conn) ResetObjects(t *Table) ([]Obj, error) {
return cc.getObj(nil, t, unix.NFT_MSG_GETOBJ_RESET)
}
func objFromMsg(msg netlink.Message) (Obj, error) {
func objFromMsg(msg netlink.Message, returnLegacyType bool) (Obj, error) {
if got, want1, want2 := msg.Header.Type, newObjHeaderType, delObjHeaderType; got != want1 && got != want2 {
return nil, fmt.Errorf("unexpected header type: got %v, want %v or %v", got, want1, want2)
}
@ -150,38 +238,30 @@ func objFromMsg(msg netlink.Message) (Obj, error) {
case unix.NFTA_OBJ_TYPE:
objectType = ad.Uint32()
case unix.NFTA_OBJ_DATA:
switch objectType {
case unix.NFT_OBJECT_COUNTER:
o := CounterObj{
Table: table,
Name: name,
}
ad.Do(func(b []byte) error {
ad, err := netlink.NewAttributeDecoder(b)
if err != nil {
return err
}
ad.ByteOrder = binary.BigEndian
return o.unmarshal(ad)
})
return &o, ad.Err()
case NFT_OBJECT_QUOTA:
o := QuotaObj{
Table: table,
Name: name,
}
ad.Do(func(b []byte) error {
ad, err := netlink.NewAttributeDecoder(b)
if err != nil {
return err
}
ad.ByteOrder = binary.BigEndian
return o.unmarshal(ad)
})
return &o, ad.Err()
if returnLegacyType {
return objDataFromMsgLegacy(ad, table, name, objectType)
}
o := NamedObj{
Table: table,
Name: name,
Type: ObjType(objectType),
}
objs, err := parseexprfunc.ParseExprBytesFromNameFunc(byte(o.family()), ad, objByObjTypeMagic[o.Type])
if err != nil {
return nil, err
}
if len(objs) == 0 {
return nil, fmt.Errorf("objFromMsg: objs is empty for obj %v", o)
}
exprs := make([]expr.Any, len(objs))
for i := range exprs {
exprs[i] = objs[i].(expr.Any)
}
o.Obj = exprs[0]
return &o, ad.Err()
}
}
if err := ad.Err(); err != nil {
@ -190,7 +270,50 @@ func objFromMsg(msg netlink.Message) (Obj, error) {
return nil, fmt.Errorf("malformed stateful object")
}
func objDataFromMsgLegacy(ad *netlink.AttributeDecoder, table *Table, name string, objectType uint32) (Obj, error) {
switch objectType {
case unix.NFT_OBJECT_COUNTER:
o := CounterObj{
Table: table,
Name: name,
}
ad.Do(func(b []byte) error {
ad, err := netlink.NewAttributeDecoder(b)
if err != nil {
return err
}
ad.ByteOrder = binary.BigEndian
return o.unmarshal(ad)
})
return &o, ad.Err()
case unix.NFT_OBJECT_QUOTA:
o := QuotaObj{
Table: table,
Name: name,
}
ad.Do(func(b []byte) error {
ad, err := netlink.NewAttributeDecoder(b)
if err != nil {
return err
}
ad.ByteOrder = binary.BigEndian
return o.unmarshal(ad)
})
return &o, ad.Err()
}
if err := ad.Err(); err != nil {
return nil, err
}
return nil, fmt.Errorf("malformed stateful object")
}
func (cc *Conn) getObj(o Obj, t *Table, msgType uint16) ([]Obj, error) {
return cc.getObjWithLegacyType(o, t, msgType, cc.useLegacyObjType(o))
}
func (cc *Conn) getObjWithLegacyType(o Obj, t *Table, msgType uint16, returnLegacyObjType bool) ([]Obj, error) {
conn, closer, err := cc.netlinkConn()
if err != nil {
return nil, err
@ -201,7 +324,12 @@ func (cc *Conn) getObj(o Obj, t *Table, msgType uint16) ([]Obj, error) {
var flags netlink.HeaderFlags
if o != nil {
data, err = o.marshal(false)
attrs := []netlink.Attribute{
{Type: unix.NFTA_OBJ_TABLE, Data: []byte(o.table().Name + "\x00")},
{Type: unix.NFTA_OBJ_NAME, Data: []byte(o.name() + "\x00")},
{Type: unix.NFTA_OBJ_TYPE, Data: binaryutil.BigEndian.PutUint32(uint32(o.objType()))},
}
data = cc.marshalAttr(attrs)
} else {
flags = netlink.Dump
data, err = netlink.MarshalAttributes([]netlink.Attribute{
@ -230,7 +358,7 @@ func (cc *Conn) getObj(o Obj, t *Table, msgType uint16) ([]Obj, error) {
}
var objs []Obj
for _, msg := range reply {
o, err := objFromMsg(msg)
o, err := objFromMsg(msg, returnLegacyObjType)
if err != nil {
return nil, err
}
@ -239,3 +367,14 @@ func (cc *Conn) getObj(o Obj, t *Table, msgType uint16) ([]Obj, error) {
return objs, nil
}
func (cc *Conn) useLegacyObjType(o Obj) bool {
useLegacyType := true
if o != nil {
switch o.(type) {
case *NamedObj:
useLegacyType = false
}
}
return useLegacyType
}

View File

@ -15,16 +15,11 @@
package nftables
import (
"github.com/google/nftables/binaryutil"
"github.com/google/nftables/expr"
"github.com/mdlayher/netlink"
"golang.org/x/sys/unix"
)
const (
NFTA_OBJ_USERDATA = 8
NFT_OBJECT_QUOTA = 2
)
type QuotaObj struct {
Table *Table
Name string
@ -47,30 +42,6 @@ func (q *QuotaObj) unmarshal(ad *netlink.AttributeDecoder) error {
return nil
}
func (q *QuotaObj) marshal(data bool) ([]byte, error) {
flags := uint32(0)
if q.Over {
flags = unix.NFT_QUOTA_F_INV
}
obj, err := netlink.MarshalAttributes([]netlink.Attribute{
{Type: unix.NFTA_QUOTA_BYTES, Data: binaryutil.BigEndian.PutUint64(q.Bytes)},
{Type: unix.NFTA_QUOTA_CONSUMED, Data: binaryutil.BigEndian.PutUint64(q.Consumed)},
{Type: unix.NFTA_QUOTA_FLAGS, Data: binaryutil.BigEndian.PutUint32(flags)},
})
if err != nil {
return nil, err
}
attrs := []netlink.Attribute{
{Type: unix.NFTA_OBJ_TABLE, Data: []byte(q.Table.Name + "\x00")},
{Type: unix.NFTA_OBJ_NAME, Data: []byte(q.Name + "\x00")},
{Type: unix.NFTA_OBJ_TYPE, Data: binaryutil.BigEndian.PutUint32(NFT_OBJECT_QUOTA)},
}
if data {
attrs = append(attrs, netlink.Attribute{Type: unix.NLA_F_NESTED | unix.NFTA_OBJ_DATA, Data: obj})
}
return netlink.MarshalAttributes(attrs)
}
func (q *QuotaObj) table() *Table {
return q.Table
}
@ -78,3 +49,19 @@ func (q *QuotaObj) table() *Table {
func (q *QuotaObj) family() TableFamily {
return q.Table.Family
}
func (q *QuotaObj) data() expr.Any {
return &expr.Quota{
Bytes: q.Bytes,
Consumed: q.Consumed,
Over: q.Over,
}
}
func (q *QuotaObj) name() string {
return q.Name
}
func (q *QuotaObj) objType() ObjType {
return ObjTypeQuota
}