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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 (
"fmt"
"net"
"reflect"
"testing"
"github.com/google/gopacket"
)
// testPacketGRE is the packet:
// 15:08:08.003196 IP 192.168.1.1 > 192.168.1.2: GREv0, length 88: IP 172.16.1.1 > 172.16.2.1: ICMP echo request, id 4724, seq 1, length 64
// 0x0000: 3a56 6b69 595e 8e7a 12c3 a971 0800 4500 :VkiY^.z...q..E.
// 0x0010: 006c 843c 4000 402f 32d3 c0a8 0101 c0a8 .l.<@.@/2.......
// 0x0020: 0102 0000 0800 4500 0054 0488 4000 4001 ......E..T..@.@.
// 0x0030: dafe ac10 0101 ac10 0201 0800 82c4 1274 ...............t
// 0x0040: 0001 c892 a354 0000 0000 380c 0000 0000 .....T....8.....
// 0x0050: 0000 1011 1213 1415 1617 1819 1a1b 1c1d ................
// 0x0060: 1e1f 2021 2223 2425 2627 2829 2a2b 2c2d ...!"#$%&'()*+,-
// 0x0070: 2e2f 3031 3233 3435 3637 ./01234567
var testPacketGRE = []byte{
0x3a, 0x56, 0x6b, 0x69, 0x59, 0x5e, 0x8e, 0x7a, 0x12, 0xc3, 0xa9, 0x71, 0x08, 0x00, 0x45, 0x00,
0x00, 0x6c, 0x84, 0x3c, 0x40, 0x00, 0x40, 0x2f, 0x32, 0xd3, 0xc0, 0xa8, 0x01, 0x01, 0xc0, 0xa8,
0x01, 0x02, 0x00, 0x00, 0x08, 0x00, 0x45, 0x00, 0x00, 0x54, 0x04, 0x88, 0x40, 0x00, 0x40, 0x01,
0xda, 0xfe, 0xac, 0x10, 0x01, 0x01, 0xac, 0x10, 0x02, 0x01, 0x08, 0x00, 0x82, 0xc4, 0x12, 0x74,
0x00, 0x01, 0xc8, 0x92, 0xa3, 0x54, 0x00, 0x00, 0x00, 0x00, 0x38, 0x0c, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d,
0x1e, 0x1f, 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d,
0x2e, 0x2f, 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
}
func TestPacketGRE(t *testing.T) {
p := gopacket.NewPacket(testPacketGRE, LinkTypeEthernet, gopacket.Default)
if p.ErrorLayer() != nil {
t.Error("Failed to decode packet:", p.ErrorLayer().Error())
}
checkLayers(p, []gopacket.LayerType{LayerTypeEthernet, LayerTypeIPv4, LayerTypeGRE, LayerTypeIPv4, LayerTypeICMPv4, gopacket.LayerTypePayload}, t)
if got, ok := p.Layer(LayerTypeGRE).(*GRE); ok {
want := &GRE{
BaseLayer: BaseLayer{testPacketGRE[34:38], testPacketGRE[38:]},
Protocol: EthernetTypeIPv4,
}
if !reflect.DeepEqual(want, got) {
t.Errorf("GRE layer mismatch, \nwant %#v\ngot %#v\n", want, got)
}
}
}
func BenchmarkDecodePacketGRE(b *testing.B) {
for i := 0; i < b.N; i++ {
gopacket.NewPacket(testPacketGRE, LinkTypeEthernet, gopacket.NoCopy)
}
}
var testIPv4OverGRE = []gopacket.SerializableLayer{
&Ethernet{
SrcMAC: net.HardwareAddr{142, 122, 18, 195, 169, 113},
DstMAC: net.HardwareAddr{58, 86, 107, 105, 89, 94},
EthernetType: EthernetTypeIPv4,
},
&IPv4{
Version: 4,
SrcIP: net.IP{192, 168, 1, 1},
DstIP: net.IP{192, 168, 1, 2},
Protocol: IPProtocolGRE,
Flags: IPv4DontFragment,
TTL: 64,
Id: 33852,
IHL: 5,
},
&GRE{
Protocol: EthernetTypeIPv4,
},
&IPv4{
Version: 4,
SrcIP: net.IP{172, 16, 1, 1},
DstIP: net.IP{172, 16, 2, 1},
Protocol: IPProtocolICMPv4,
Flags: IPv4DontFragment,
TTL: 64,
IHL: 5,
Id: 1160,
},
&ICMPv4{
TypeCode: CreateICMPv4TypeCode(ICMPv4TypeEchoRequest, 0),
Id: 4724,
Seq: 1,
},
gopacket.Payload{
0xc8, 0x92, 0xa3, 0x54, 0x00, 0x00, 0x00, 0x00, 0x38, 0x0c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
},
}
func TestIPv4OverGREEncode(t *testing.T) {
b := gopacket.NewSerializeBuffer()
opts := gopacket.SerializeOptions{
ComputeChecksums: true,
FixLengths: true,
}
if err := gopacket.SerializeLayers(b, opts, testIPv4OverGRE...); err != nil {
t.Errorf("Unable to serialize: %v", err)
}
p := gopacket.NewPacket(b.Bytes(), LinkTypeEthernet, gopacket.Default)
if p.ErrorLayer() != nil {
t.Error("Failed to decode packet:", p.ErrorLayer().Error())
}
checkLayers(p, []gopacket.LayerType{LayerTypeEthernet, LayerTypeIPv4, LayerTypeGRE, LayerTypeIPv4, LayerTypeICMPv4, gopacket.LayerTypePayload}, t)
if got, want := b.Bytes(), testPacketGRE; !reflect.DeepEqual(want, got) {
t.Errorf("Encoding mismatch, \nwant: %v\ngot %v\n", want, got)
}
}
func BenchmarkEncodePacketGRE(b *testing.B) {
buf := gopacket.NewSerializeBuffer()
opts := gopacket.SerializeOptions{
ComputeChecksums: true,
FixLengths: true,
}
for i := 0; i < b.N; i++ {
gopacket.SerializeLayers(buf, opts, testIPv4OverGRE...)
buf.Clear()
}
}
// testPacketEthernetOverGRE is the packet:
// 11:01:38.124768 IP 192.168.1.1 > 192.168.1.2: GREv0, length 102: IP 172.16.1.1 > 172.16.1.2: ICMP echo request, id 3842, seq 1, length 64
// 0x0000: ea6b 4cd3 5513 d6b9 d880 56ef 0800 4500 .kL.U.....V...E.
// 0x0010: 007a 0acd 4000 402f ac34 c0a8 0101 c0a8 .z..@.@/.4......
// 0x0020: 0102 0000 6558 aa6a 36e6 c630 6e32 3ec7 ....eX.j6..0n2>.
// 0x0030: 9def 0800 4500 0054 d970 4000 4001 0715 ....E..T.p@.@...
// 0x0040: ac10 0101 ac10 0102 0800 3f15 0f02 0001 ..........?.....
// 0x0050: 82d9 b154 0000 0000 b5e6 0100 0000 0000 ...T............
// 0x0060: 1011 1213 1415 1617 1819 1a1b 1c1d 1e1f ................
// 0x0070: 2021 2223 2425 2627 2829 2a2b 2c2d 2e2f .!"#$%&'()*+,-./
// 0x0080: 3031 3233 3435 3637 01234567
var testPacketEthernetOverGRE = []byte{
0xea, 0x6b, 0x4c, 0xd3, 0x55, 0x13, 0xd6, 0xb9, 0xd8, 0x80, 0x56, 0xef, 0x08, 0x00, 0x45, 0x00,
0x00, 0x7a, 0x0a, 0xcd, 0x40, 0x00, 0x40, 0x2f, 0xac, 0x34, 0xc0, 0xa8, 0x01, 0x01, 0xc0, 0xa8,
0x01, 0x02, 0x00, 0x00, 0x65, 0x58, 0xaa, 0x6a, 0x36, 0xe6, 0xc6, 0x30, 0x6e, 0x32, 0x3e, 0xc7,
0x9d, 0xef, 0x08, 0x00, 0x45, 0x00, 0x00, 0x54, 0xd9, 0x70, 0x40, 0x00, 0x40, 0x01, 0x07, 0x15,
0xac, 0x10, 0x01, 0x01, 0xac, 0x10, 0x01, 0x02, 0x08, 0x00, 0x3f, 0x15, 0x0f, 0x02, 0x00, 0x01,
0x82, 0xd9, 0xb1, 0x54, 0x00, 0x00, 0x00, 0x00, 0xb5, 0xe6, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00,
0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
}
func TestPacketEthernetOverGRE(t *testing.T) {
p := gopacket.NewPacket(testPacketEthernetOverGRE, LinkTypeEthernet, gopacket.Default)
if p.ErrorLayer() != nil {
t.Error("Failed to decode packet:", p.ErrorLayer().Error())
}
checkLayers(p, []gopacket.LayerType{LayerTypeEthernet, LayerTypeIPv4, LayerTypeGRE, LayerTypeEthernet, LayerTypeIPv4, LayerTypeICMPv4, gopacket.LayerTypePayload}, t)
if got, ok := p.Layer(LayerTypeGRE).(*GRE); ok {
want := &GRE{
BaseLayer: BaseLayer{testPacketEthernetOverGRE[34:38], testPacketEthernetOverGRE[38:]},
Protocol: EthernetTypeTransparentEthernetBridging,
}
if !reflect.DeepEqual(want, got) {
t.Errorf("GRE layer mismatch, \nwant %#v\ngot %#v\n", want, got)
}
}
}
func BenchmarkDecodePacketEthernetOverGRE(b *testing.B) {
for i := 0; i < b.N; i++ {
gopacket.NewPacket(testPacketEthernetOverGRE, LinkTypeEthernet, gopacket.NoCopy)
}
}
var testEthernetOverGRE = []gopacket.SerializableLayer{
&Ethernet{
SrcMAC: net.HardwareAddr{0xd6, 0xb9, 0xd8, 0x80, 0x56, 0xef},
DstMAC: net.HardwareAddr{0xea, 0x6b, 0x4c, 0xd3, 0x55, 0x13},
EthernetType: EthernetTypeIPv4,
},
&IPv4{
Version: 4,
SrcIP: net.IP{192, 168, 1, 1},
DstIP: net.IP{192, 168, 1, 2},
Protocol: IPProtocolGRE,
Flags: IPv4DontFragment,
TTL: 64,
Id: 2765,
IHL: 5,
},
&GRE{
Protocol: EthernetTypeTransparentEthernetBridging,
},
&Ethernet{
SrcMAC: net.HardwareAddr{0x6e, 0x32, 0x3e, 0xc7, 0x9d, 0xef},
DstMAC: net.HardwareAddr{0xaa, 0x6a, 0x36, 0xe6, 0xc6, 0x30},
EthernetType: EthernetTypeIPv4,
},
&IPv4{
Version: 4,
SrcIP: net.IP{172, 16, 1, 1},
DstIP: net.IP{172, 16, 1, 2},
Protocol: IPProtocolICMPv4,
Flags: IPv4DontFragment,
TTL: 64,
IHL: 5,
Id: 55664,
},
&ICMPv4{
TypeCode: CreateICMPv4TypeCode(ICMPv4TypeEchoRequest, 0),
Id: 3842,
Seq: 1,
},
gopacket.Payload{
0x82, 0xd9, 0xb1, 0x54, 0x00, 0x00, 0x00, 0x00, 0xb5, 0xe6, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00,
0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
},
}
func TestEthernetOverGREEncode(t *testing.T) {
b := gopacket.NewSerializeBuffer()
opts := gopacket.SerializeOptions{
ComputeChecksums: true,
FixLengths: true,
}
if err := gopacket.SerializeLayers(b, opts, testEthernetOverGRE...); err != nil {
t.Errorf("Unable to serialize: %v", err)
}
p := gopacket.NewPacket(b.Bytes(), LinkTypeEthernet, gopacket.Default)
if p.ErrorLayer() != nil {
t.Error("Failed to decode packet:", p.ErrorLayer().Error())
}
checkLayers(p, []gopacket.LayerType{LayerTypeEthernet, LayerTypeIPv4, LayerTypeGRE, LayerTypeEthernet, LayerTypeIPv4, LayerTypeICMPv4, gopacket.LayerTypePayload}, t)
if got, want := b.Bytes(), testPacketEthernetOverGRE; !reflect.DeepEqual(want, got) {
t.Errorf("Encoding mismatch, \nwant: %v\ngot %v\n", want, got)
}
}
func BenchmarkEncodePacketEthernetOverGRE(b *testing.B) {
buf := gopacket.NewSerializeBuffer()
opts := gopacket.SerializeOptions{
ComputeChecksums: true,
FixLengths: true,
}
for i := 0; i < b.N; i++ {
gopacket.SerializeLayers(buf, opts, testEthernetOverGRE...)
buf.Clear()
}
}
var testGREChecksum = map[uint16][]gopacket.SerializableLayer{
0x77ff: {
&Ethernet{
SrcMAC: net.HardwareAddr{0xc2, 0x00, 0x57, 0x75, 0x00, 0x00},
DstMAC: net.HardwareAddr{0xc2, 0x01, 0x57, 0x75, 0x00, 0x00},
EthernetType: EthernetTypeIPv4,
},
&IPv4{
Version: 4,
SrcIP: net.IP{10, 0, 0, 1},
DstIP: net.IP{10, 0, 0, 2},
Protocol: IPProtocolGRE,
TTL: 255,
Id: 10,
IHL: 5,
},
&GRE{
Protocol: EthernetTypeIPv4,
ChecksumPresent: true,
},
&IPv4{
Version: 4,
SrcIP: net.IP{1, 1, 1, 1},
DstIP: net.IP{2, 2, 2, 2},
Protocol: IPProtocolICMPv4,
TTL: 255,
IHL: 5,
Id: 10,
},
&ICMPv4{
TypeCode: CreateICMPv4TypeCode(ICMPv4TypeEchoRequest, 0),
Id: 2,
Seq: 0,
},
gopacket.Payload{
0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0xbe, 0x70, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd,
0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd,
0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd,
0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd,
0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd, 0xab, 0xcd,
},
},
0x8475: {
&Ethernet{
SrcMAC: net.HardwareAddr{0xc2, 0x00, 0x57, 0x75, 0x00, 0x00},
DstMAC: net.HardwareAddr{0xc2, 0x01, 0x57, 0x75, 0x00, 0x00},
EthernetType: EthernetTypeIPv4,
},
&IPv4{
Version: 4,
SrcIP: net.IP{10, 0, 0, 1},
DstIP: net.IP{10, 0, 0, 2},
Protocol: IPProtocolGRE,
TTL: 255,
Id: 10,
IHL: 5,
},
&GRE{
Protocol: EthernetTypeIPv4,
ChecksumPresent: true,
},
&IPv4{
Version: 4,
SrcIP: net.IP{2, 3, 4, 5},
DstIP: net.IP{2, 3, 4, 50},
Protocol: IPProtocolUDP,
TTL: 1,
IHL: 5,
Flags: IPv4DontFragment,
Id: 964,
},
&UDP{
SrcPort: 41781,
DstPort: 33434,
},
gopacket.Payload{
0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,
0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f,
},
},
}
func TestGREChecksum(t *testing.T) {
buf := gopacket.NewSerializeBuffer()
opts := gopacket.SerializeOptions{
ComputeChecksums: true,
FixLengths: true,
}
for cksum, packet := range testGREChecksum {
buf.Clear()
if err := setNetworkLayer(packet); err != nil {
t.Errorf("Failed to set network layer: %v", err)
continue
}
if err := gopacket.SerializeLayers(buf, opts, packet...); err != nil {
t.Errorf("Failed to serialize packet: %v", err)
continue
}
p := gopacket.NewPacket(buf.Bytes(), LinkTypeEthernet, gopacket.Default)
t.Log(p)
if p.ErrorLayer() != nil {
t.Error("Failed to decode packet:", p.ErrorLayer().Error())
continue
}
if got, ok := p.Layer(LayerTypeGRE).(*GRE); ok {
if got.Checksum != cksum {
t.Errorf("Incorrect checksum calculated for GRE packet: want %v, got %v", cksum, got.Checksum)
}
}
}
}
func setNetworkLayer(layers []gopacket.SerializableLayer) error {
type setNetworkLayerForChecksum interface {
SetNetworkLayerForChecksum(gopacket.NetworkLayer) error
}
var l gopacket.NetworkLayer
for _, layer := range layers {
if n, ok := layer.(gopacket.NetworkLayer); ok {
l = n
}
if s, ok := layer.(setNetworkLayerForChecksum); ok {
if l == nil {
return fmt.Errorf("no enclosing network layer found before: %v", s)
}
if err := s.SetNetworkLayerForChecksum(l); err != nil {
return fmt.Errorf("failed to set network layer(%v) on layer(%v): %v", l, s, err)
}
}
}
return nil
}
|
