blob: 19163fa37ee7d4f50574854baf1ab2b24d30bac2 [file] [log] [blame]
Holger Hildebrandtfa074992020-03-27 15:42:06 +00001// Copyright 2012 Google, Inc. All rights reserved.
2//
3// Use of this source code is governed by a BSD-style license
4// that can be found in the LICENSE file in the root of the source
5// tree.
6
7package layers
8
9import (
10 "encoding/binary"
11 "github.com/google/gopacket"
12)
13
14// IPSecAH is the authentication header for IPv4/6 defined in
15// http://tools.ietf.org/html/rfc2402
16type IPSecAH struct {
17 // While the auth header can be used for both IPv4 and v6, its format is that of
18 // an IPv6 extension (NextHeader, PayloadLength, etc...), so we use ipv6ExtensionBase
19 // to build it.
20 ipv6ExtensionBase
21 Reserved uint16
22 SPI, Seq uint32
23 AuthenticationData []byte
24}
25
26// LayerType returns LayerTypeIPSecAH.
27func (i *IPSecAH) LayerType() gopacket.LayerType { return LayerTypeIPSecAH }
28
29func decodeIPSecAH(data []byte, p gopacket.PacketBuilder) error {
30 i := &IPSecAH{
31 ipv6ExtensionBase: ipv6ExtensionBase{
32 NextHeader: IPProtocol(data[0]),
33 HeaderLength: data[1],
34 },
35 Reserved: binary.BigEndian.Uint16(data[2:4]),
36 SPI: binary.BigEndian.Uint32(data[4:8]),
37 Seq: binary.BigEndian.Uint32(data[8:12]),
38 }
39 i.ActualLength = (int(i.HeaderLength) + 2) * 4
40 i.AuthenticationData = data[12:i.ActualLength]
41 i.Contents = data[:i.ActualLength]
42 i.Payload = data[i.ActualLength:]
43 p.AddLayer(i)
44 return p.NextDecoder(i.NextHeader)
45}
46
47// IPSecESP is the encapsulating security payload defined in
48// http://tools.ietf.org/html/rfc2406
49type IPSecESP struct {
50 BaseLayer
51 SPI, Seq uint32
52 // Encrypted contains the encrypted set of bytes sent in an ESP
53 Encrypted []byte
54}
55
56// LayerType returns LayerTypeIPSecESP.
57func (i *IPSecESP) LayerType() gopacket.LayerType { return LayerTypeIPSecESP }
58
59func decodeIPSecESP(data []byte, p gopacket.PacketBuilder) error {
60 i := &IPSecESP{
61 BaseLayer: BaseLayer{data, nil},
62 SPI: binary.BigEndian.Uint32(data[:4]),
63 Seq: binary.BigEndian.Uint32(data[4:8]),
64 Encrypted: data[8:],
65 }
66 p.AddLayer(i)
67 return nil
68}