diff --git a/expr/objref.go b/expr/objref.go new file mode 100644 index 0000000..966d826 --- /dev/null +++ b/expr/objref.go @@ -0,0 +1,58 @@ +// 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 ( + "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() ([]byte, error) { + data, err := 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?! + }) + 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) unmarshal(data []byte) error { + attrs, err := netlink.UnmarshalAttributes(data) + if err != nil { + return err + } + for _, attr := range attrs { + switch attr.Type { + case unix.NFTA_OBJREF_IMM_TYPE: + e.Type = int(binaryutil.BigEndian.Uint32(attr.Data)) + case unix.NFTA_OBJREF_IMM_NAME: + e.Name = string(attr.Data) + } + } + + return nil +}