aboutsummaryrefslogtreecommitdiffstats
path: root/vendor/github.com/google/gopacket/layers/loopback.go
diff options
context:
space:
mode:
Diffstat (limited to 'vendor/github.com/google/gopacket/layers/loopback.go')
-rw-r--r--vendor/github.com/google/gopacket/layers/loopback.go80
1 files changed, 80 insertions, 0 deletions
diff --git a/vendor/github.com/google/gopacket/layers/loopback.go b/vendor/github.com/google/gopacket/layers/loopback.go
new file mode 100644
index 0000000..839f760
--- /dev/null
+++ b/vendor/github.com/google/gopacket/layers/loopback.go
@@ -0,0 +1,80 @@
+// Copyright 2012 Google, Inc. All rights reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the LICENSE file in the root of the source
+// tree.
+
+package layers
+
+import (
+ "encoding/binary"
+ "errors"
+ "fmt"
+
+ "github.com/google/gopacket"
+)
+
+// Loopback contains the header for loopback encapsulation. This header is
+// used by both BSD and OpenBSD style loopback decoding (pcap's DLT_NULL
+// and DLT_LOOP, respectively).
+type Loopback struct {
+ BaseLayer
+ Family ProtocolFamily
+}
+
+// LayerType returns LayerTypeLoopback.
+func (l *Loopback) LayerType() gopacket.LayerType { return LayerTypeLoopback }
+
+// DecodeFromBytes decodes the given bytes into this layer.
+func (l *Loopback) DecodeFromBytes(data []byte, df gopacket.DecodeFeedback) error {
+ if len(data) < 4 {
+ return errors.New("Loopback packet too small")
+ }
+
+ // The protocol could be either big-endian or little-endian, we're
+ // not sure. But we're PRETTY sure that the value is less than
+ // 256, so we can check the first two bytes.
+ var prot uint32
+ if data[0] == 0 && data[1] == 0 {
+ prot = binary.BigEndian.Uint32(data[:4])
+ } else {
+ prot = binary.LittleEndian.Uint32(data[:4])
+ }
+ if prot > 0xFF {
+ return fmt.Errorf("Invalid loopback protocol %q", data[:4])
+ }
+
+ l.Family = ProtocolFamily(prot)
+ l.BaseLayer = BaseLayer{data[:4], data[4:]}
+ return nil
+}
+
+// CanDecode returns the set of layer types that this DecodingLayer can decode.
+func (l *Loopback) CanDecode() gopacket.LayerClass {
+ return LayerTypeLoopback
+}
+
+// NextLayerType returns the layer type contained by this DecodingLayer.
+func (l *Loopback) NextLayerType() gopacket.LayerType {
+ return l.Family.LayerType()
+}
+
+// SerializeTo writes the serialized form of this layer into the
+// SerializationBuffer, implementing gopacket.SerializableLayer.
+func (l *Loopback) SerializeTo(b gopacket.SerializeBuffer, opts gopacket.SerializeOptions) error {
+ bytes, err := b.PrependBytes(4)
+ if err != nil {
+ return err
+ }
+ binary.LittleEndian.PutUint32(bytes, uint32(l.Family))
+ return nil
+}
+
+func decodeLoopback(data []byte, p gopacket.PacketBuilder) error {
+ l := Loopback{}
+ if err := l.DecodeFromBytes(data, gopacket.NilDecodeFeedback); err != nil {
+ return err
+ }
+ p.AddLayer(&l)
+ return p.NextDecoder(l.Family)
+}