// 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 Counter struct { Bytes uint64 Packets uint64 } func (e *Counter) 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("counter\x00")}, {Type: unix.NLA_F_NESTED | unix.NFTA_EXPR_DATA, Data: data}, }) } func (e *Counter) marshalData(fam byte) ([]byte, error) { return netlink.MarshalAttributes([]netlink.Attribute{ {Type: unix.NFTA_COUNTER_BYTES, Data: binaryutil.BigEndian.PutUint64(e.Bytes)}, {Type: unix.NFTA_COUNTER_PACKETS, Data: binaryutil.BigEndian.PutUint64(e.Packets)}, }) } func (e *Counter) 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_COUNTER_BYTES: e.Bytes = ad.Uint64() case unix.NFTA_COUNTER_PACKETS: e.Packets = ad.Uint64() } } return ad.Err() }