ODPM 266: Go-libmemif + 2 examples.

[govpp.git] / vendor / github.com / google / gopacket / layers / ctp.go

diff --git a/vendor/github.com/google/gopacket/layers/ctp.go b/vendor/github.com/google/gopacket/layers/ctp.go
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+++ b/vendor/github.com/google/gopacket/layers/ctp.go
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+// 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"
+       "fmt"
+       "github.com/google/gopacket"
+)
+
+// EthernetCTPFunction is the function code used by the EthernetCTP protocol to identify each
+// EthernetCTP layer.
+type EthernetCTPFunction uint16
+
+// EthernetCTPFunction values.
+const (
+       EthernetCTPFunctionReply       EthernetCTPFunction = 1
+       EthernetCTPFunctionForwardData EthernetCTPFunction = 2
+)
+
+// EthernetCTP implements the EthernetCTP protocol, see http://www.mit.edu/people/jhawk/ctp.html.
+// We split EthernetCTP up into the top-level EthernetCTP layer, followed by zero or more
+// EthernetCTPForwardData layers, followed by a final EthernetCTPReply layer.
+type EthernetCTP struct {
+       BaseLayer
+       SkipCount uint16
+}
+
+// LayerType returns gopacket.LayerTypeEthernetCTP.
+func (c *EthernetCTP) LayerType() gopacket.LayerType {
+       return LayerTypeEthernetCTP
+}
+
+// EthernetCTPForwardData is the ForwardData layer inside EthernetCTP.  See EthernetCTP's docs for more
+// details.
+type EthernetCTPForwardData struct {
+       BaseLayer
+       Function       EthernetCTPFunction
+       ForwardAddress []byte
+}
+
+// LayerType returns gopacket.LayerTypeEthernetCTPForwardData.
+func (c *EthernetCTPForwardData) LayerType() gopacket.LayerType {
+       return LayerTypeEthernetCTPForwardData
+}
+
+// ForwardEndpoint returns the EthernetCTPForwardData ForwardAddress as an endpoint.
+func (c *EthernetCTPForwardData) ForwardEndpoint() gopacket.Endpoint {
+       return gopacket.NewEndpoint(EndpointMAC, c.ForwardAddress)
+}
+
+// EthernetCTPReply is the Reply layer inside EthernetCTP.  See EthernetCTP's docs for more details.
+type EthernetCTPReply struct {
+       BaseLayer
+       Function      EthernetCTPFunction
+       ReceiptNumber uint16
+       Data          []byte
+}
+
+// LayerType returns gopacket.LayerTypeEthernetCTPReply.
+func (c *EthernetCTPReply) LayerType() gopacket.LayerType {
+       return LayerTypeEthernetCTPReply
+}
+
+// Payload returns the EthernetCTP reply's Data bytes.
+func (c *EthernetCTPReply) Payload() []byte { return c.Data }
+
+func decodeEthernetCTP(data []byte, p gopacket.PacketBuilder) error {
+       c := &EthernetCTP{
+               SkipCount: binary.LittleEndian.Uint16(data[:2]),
+               BaseLayer: BaseLayer{data[:2], data[2:]},
+       }
+       if c.SkipCount%2 != 0 {
+               return fmt.Errorf("EthernetCTP skip count is odd: %d", c.SkipCount)
+       }
+       p.AddLayer(c)
+       return p.NextDecoder(gopacket.DecodeFunc(decodeEthernetCTPFromFunctionType))
+}
+
+// decodeEthernetCTPFromFunctionType reads in the first 2 bytes to determine the EthernetCTP
+// layer type to decode next, then decodes based on that.
+func decodeEthernetCTPFromFunctionType(data []byte, p gopacket.PacketBuilder) error {
+       function := EthernetCTPFunction(binary.LittleEndian.Uint16(data[:2]))
+       switch function {
+       case EthernetCTPFunctionReply:
+               reply := &EthernetCTPReply{
+                       Function:      function,
+                       ReceiptNumber: binary.LittleEndian.Uint16(data[2:4]),
+                       Data:          data[4:],
+                       BaseLayer:     BaseLayer{data, nil},
+               }
+               p.AddLayer(reply)
+               p.SetApplicationLayer(reply)
+               return nil
+       case EthernetCTPFunctionForwardData:
+               forward := &EthernetCTPForwardData{
+                       Function:       function,
+                       ForwardAddress: data[2:8],
+                       BaseLayer:      BaseLayer{data[:8], data[8:]},
+               }
+               p.AddLayer(forward)
+               return p.NextDecoder(gopacket.DecodeFunc(decodeEthernetCTPFromFunctionType))
+       }
+       return fmt.Errorf("Unknown EthernetCTP function type %v", function)
+}