nftables/expr/objref.go

65 lines
1.7 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 expr
import (
"encoding/binary"
"github.com/google/nftables/binaryutil"
"github.com/mdlayher/netlink"
"golang.org/x/sys/unix"
)
type Objref struct {
Type int // TODO: enum
Name string
}
func (e *Objref) marshal(fam byte) ([]byte, error) {
data, err := e.marshalData(fam)
if err != nil {
return nil, err
}
return netlink.MarshalAttributes([]netlink.Attribute{
{Type: unix.NFTA_EXPR_NAME, Data: []byte("objref\x00")},
{Type: unix.NLA_F_NESTED | unix.NFTA_EXPR_DATA, Data: data},
})
}
func (e *Objref) marshalData(fam byte) ([]byte, error) {
return netlink.MarshalAttributes([]netlink.Attribute{
{Type: unix.NFTA_OBJREF_IMM_TYPE, Data: binaryutil.BigEndian.PutUint32(uint32(e.Type))},
{Type: unix.NFTA_OBJREF_IMM_NAME, Data: []byte(e.Name)}, // NOT \x00-terminated?!
})
}
func (e *Objref) unmarshal(fam byte, data []byte) error {
ad, err := netlink.NewAttributeDecoder(data)
if err != nil {
return err
}
ad.ByteOrder = binary.BigEndian
for ad.Next() {
switch ad.Type() {
case unix.NFTA_OBJREF_IMM_TYPE:
e.Type = int(ad.Uint32())
case unix.NFTA_OBJREF_IMM_NAME:
e.Name = ad.String()
}
}
return ad.Err()
}