nftables/counter.go

71 lines
2.0 KiB
Go

// Copyright 2018 Google LLC. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package nftables
import (
"github.com/google/nftables/binaryutil"
"github.com/mdlayher/netlink"
"golang.org/x/sys/unix"
)
// CounterObj implements Obj.
type CounterObj struct {
Table *Table
Name string // e.g. “fwded”
Bytes uint64
Packets uint64
}
func (c *CounterObj) unmarshal(ad *netlink.AttributeDecoder) error {
for ad.Next() {
switch ad.Type() {
case unix.NFTA_COUNTER_BYTES:
c.Bytes = ad.Uint64()
case unix.NFTA_COUNTER_PACKETS:
c.Packets = ad.Uint64()
}
}
return ad.Err()
}
func (c *CounterObj) table() *Table {
return c.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
}
const NFT_OBJECT_COUNTER = 1 // TODO: get into x/sys/unix
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(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)
}