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// Copyright 2016 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 (
"crypto/rand"
"github.com/google/gopacket"
"io"
"reflect"
"testing"
)
//******************************************************************************
// checkNTP() uses the ntp.go code to analyse the packet bytes as an NTP UDP
// packet and generate an NTP object. It then compares the generated NTP object
// with the one provided and throws an error if there is any difference.
// The desc argument is output with any failure message to identify the test.
func checkNTP(desc string, t *testing.T, packetBytes []byte, pExpectedNTP *NTP) {
// Analyse the packet bytes, yielding a new packet object p.
p := gopacket.NewPacket(packetBytes, LinkTypeEthernet, gopacket.Default)
if p.ErrorLayer() != nil {
t.Errorf("Failed to decode packet %s: %v", desc, p.ErrorLayer().Error())
}
// Ensure that the packet analysis yielded the correct set of layers:
// Link Layer = Ethernet.
// Network Layer = IPv4.
// Transport Layer = UDP.
// Application Layer = NTP.
checkLayers(p, []gopacket.LayerType{
LayerTypeEthernet,
LayerTypeIPv4,
LayerTypeUDP,
LayerTypeNTP}, t)
// Select the Application (NTP) layer.
pResultNTP, ok := p.ApplicationLayer().(*NTP)
if !ok {
t.Error("No NTP layer type found in packet in " + desc + ".")
}
// Compare the generated NTP object with the expected NTP object.
if !reflect.DeepEqual(pResultNTP, pExpectedNTP) {
t.Errorf("NTP packet processing failed for packet "+desc+
":\ngot :\n%#v\n\nwant :\n%#v\n\n", pResultNTP, pExpectedNTP)
}
buf := gopacket.NewSerializeBuffer()
opts := gopacket.SerializeOptions{}
err := pResultNTP.SerializeTo(buf, opts)
if err != nil {
t.Error(err)
}
if !reflect.DeepEqual(pResultNTP.BaseLayer.Contents, buf.Bytes()) {
t.Errorf("NTP packet serialization failed for packet "+desc+
":\ngot :\n%x\n\nwant :\n%x\n\n", buf.Bytes(), packetBytes)
}
}
//******************************************************************************
func TestNTPOne(t *testing.T) {
// This test packet is the first NTP packet in the NTP sample capture
// pcap file NTP_sync.pcap on the Wireshark sample captures page:
//
// https://wiki.wireshark.org/SampleCaptures
// https://wiki.wireshark.org/SampleCaptures?action=AttachFile&do=get&target=NTP_sync.pcap
var testPacketNTP = []byte{
0x00, 0x0c, 0x41, 0x82, 0xb2, 0x53, 0x00, 0xd0,
0x59, 0x6c, 0x40, 0x4e, 0x08, 0x00, 0x45, 0x00,
0x00, 0x4c, 0x0a, 0x42, 0x00, 0x00, 0x80, 0x11,
0xb5, 0xfa, 0xc0, 0xa8, 0x32, 0x32, 0x43, 0x81,
0x44, 0x09, 0x00, 0x7b, 0x00, 0x7b, 0x00, 0x38,
0xf8, 0xd2, 0xd9, 0x00, 0x0a, 0xfa, 0x00, 0x00,
0x00, 0x00, 0x00, 0x01, 0x02, 0x90, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0xc5, 0x02, 0x04, 0xec, 0xec, 0x42,
0xee, 0x92,
}
// Assemble the NTP object that we expect to emerge from this test.
pExpectedNTP := &NTP{
BaseLayer: BaseLayer{
Contents: []byte{0xd9, 0x0, 0xa, 0xfa, 0x0, 0x0, 0x0, 0x0, 0x0,
0x1, 0x2, 0x90, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0,
0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0,
0x0, 0x0, 0x0, 0x0, 0x0, 0xc5, 0x2, 0x4, 0xec, 0xec, 0x42, 0xee, 0x92},
Payload: nil,
},
LeapIndicator: 3,
Version: 3,
Mode: 1,
Stratum: 0,
Poll: 10,
Precision: -6,
RootDelay: 0,
RootDispersion: 0x10290,
ReferenceID: 0,
ReferenceTimestamp: 0,
OriginTimestamp: 0,
ReceiveTimestamp: 0,
TransmitTimestamp: 0xc50204ecec42ee92,
ExtensionBytes: []byte{},
}
checkNTP("test01", t, testPacketNTP, pExpectedNTP)
}
//******************************************************************************
func TestNTPTwo(t *testing.T) {
// This test packet is packet #18 in the NTP sample capture
// pcap file NTP_sync.pcap on the Wireshark sample captures page:
//
// https://wiki.wireshark.org/SampleCaptures
// https://wiki.wireshark.org/SampleCaptures?action=AttachFile&do=get&target=NTP_sync.pcap
//
// This packet was chosen because it is the first NTP packet after the first
// NTP packet that has non-zero timestamps.
var testPacketNTP = []byte{
0x00, 0xd0, 0x59, 0x6c, 0x40, 0x4e, 0x00, 0x0c,
0x41, 0x82, 0xb2, 0x53, 0x08, 0x00, 0x45, 0x00,
0x00, 0x4c, 0x32, 0x46, 0x40, 0x00, 0x2f, 0x11,
0xa8, 0x18, 0x45, 0x2c, 0x39, 0x3c, 0xc0, 0xa8,
0x32, 0x32, 0x00, 0x7b, 0x00, 0x7b, 0x00, 0x38,
0x09, 0x58, 0x1a, 0x03, 0x0a, 0xee, 0x00, 0x00,
0x1b, 0xf7, 0x00, 0x00, 0x14, 0xec, 0x51, 0xae,
0x80, 0xb7, 0xc5, 0x02, 0x03, 0x4c, 0x8d, 0x0e,
0x66, 0xcb, 0xc5, 0x02, 0x04, 0xec, 0xec, 0x42,
0xee, 0x92, 0xc5, 0x02, 0x04, 0xeb, 0xcf, 0x49,
0x59, 0xe6, 0xc5, 0x02, 0x04, 0xeb, 0xcf, 0x4c,
0x6e, 0x6e,
}
// Assemble the NTP object that we expect to emerge from this test.
pExpectedNTP := &NTP{
BaseLayer: BaseLayer{
Contents: []byte{0x1a, 0x03, 0x0a, 0xee, 0x00, 0x00,
0x1b, 0xf7, 0x00, 0x00, 0x14, 0xec, 0x51, 0xae,
0x80, 0xb7, 0xc5, 0x02, 0x03, 0x4c, 0x8d, 0x0e,
0x66, 0xcb, 0xc5, 0x02, 0x04, 0xec, 0xec, 0x42,
0xee, 0x92, 0xc5, 0x02, 0x04, 0xeb, 0xcf, 0x49,
0x59, 0xe6, 0xc5, 0x02, 0x04, 0xeb, 0xcf, 0x4c,
0x6e, 0x6e},
Payload: nil,
},
LeapIndicator: 0,
Version: 3,
Mode: 2,
Stratum: 3,
Poll: 10,
Precision: -18,
RootDelay: 0x1bf7,
RootDispersion: 0x14ec,
ReferenceID: 0x51ae80b7,
ReferenceTimestamp: 0xc502034c8d0e66cb,
OriginTimestamp: 0xc50204ecec42ee92,
ReceiveTimestamp: 0xc50204ebcf4959e6,
TransmitTimestamp: 0xc50204ebcf4c6e6e,
ExtensionBytes: []byte{},
}
checkNTP("test02", t, testPacketNTP, pExpectedNTP)
}
//******************************************************************************
func TestNTPThree(t *testing.T) {
// This test packet is packet #19 in the NTP sample capture
// pcap file NTP_sync.pcap on the Wireshark sample captures page:
//
// https://wiki.wireshark.org/SampleCaptures
// https://wiki.wireshark.org/SampleCaptures?action=AttachFile&do=get&target=NTP_sync.pcap
var testPacketNTP = []byte{
0x00, 0xd0, 0x59, 0x6c, 0x40, 0x4e, 0x00, 0x0c,
0x41, 0x82, 0xb2, 0x53, 0x08, 0x00, 0x45, 0x00,
0x00, 0x4c, 0x00, 0x00, 0x40, 0x00, 0x30, 0x11,
0x74, 0x65, 0x18, 0x7b, 0xca, 0xe6, 0xc0, 0xa8,
0x32, 0x32, 0x00, 0x7b, 0x00, 0x7b, 0x00, 0x38,
0x44, 0x05, 0x1a, 0x02, 0x0a, 0xec, 0x00, 0x00,
0x07, 0xc3, 0x00, 0x00, 0x2f, 0x80, 0xc6, 0x1e,
0x5c, 0x02, 0xc5, 0x01, 0xf9, 0x95, 0x42, 0x50,
0x82, 0xcf, 0xc5, 0x02, 0x04, 0xec, 0xec, 0x42,
0xee, 0x92, 0xc5, 0x02, 0x04, 0xeb, 0xd2, 0x35,
0x2e, 0xb5, 0xc5, 0x02, 0x04, 0xeb, 0xd2, 0x35,
0xd6, 0x7b,
}
// Assemble the NTP object that we expect to emerge from this test.
pExpectedNTP := &NTP{
BaseLayer: BaseLayer{
Contents: []byte{0x1a, 0x02, 0x0a, 0xec, 0x00, 0x00,
0x07, 0xc3, 0x00, 0x00, 0x2f, 0x80, 0xc6, 0x1e,
0x5c, 0x02, 0xc5, 0x01, 0xf9, 0x95, 0x42, 0x50,
0x82, 0xcf, 0xc5, 0x02, 0x04, 0xec, 0xec, 0x42,
0xee, 0x92, 0xc5, 0x02, 0x04, 0xeb, 0xd2, 0x35,
0x2e, 0xb5, 0xc5, 0x02, 0x04, 0xeb, 0xd2, 0x35,
0xd6, 0x7b},
Payload: nil,
},
LeapIndicator: 0,
Version: 3,
Mode: 2,
Stratum: 2,
Poll: 10,
Precision: -20,
RootDelay: 0x7c3,
RootDispersion: 0x2f80,
ReferenceID: 0xc61e5c02,
ReferenceTimestamp: 0xc501f995425082cf,
OriginTimestamp: 0xc50204ecec42ee92,
ReceiveTimestamp: 0xc50204ebd2352eb5,
TransmitTimestamp: 0xc50204ebd235d67b,
ExtensionBytes: []byte{},
}
checkNTP("test03", t, testPacketNTP, pExpectedNTP)
}
//******************************************************************************
// TestNTPIsomorphism tests whether random data gets parsed into NTP layer and
// gets serialized back from it to the same value.
func TestNTPIsomorphism(t *testing.T) {
NTPData := make([]byte, ntpMinimumRecordSizeInBytes+7)
_, err := io.ReadFull(rand.Reader, NTPData)
if err != nil {
t.Error(err)
}
ntpLayer := &NTP{}
err = ntpLayer.DecodeFromBytes(NTPData, gopacket.NilDecodeFeedback)
if err != nil {
t.Error(err)
}
buf := gopacket.NewSerializeBuffer()
opts := gopacket.SerializeOptions{}
err = ntpLayer.SerializeTo(buf, opts)
if err != nil {
t.Error(err)
}
if !reflect.DeepEqual(NTPData, buf.Bytes()) {
t.Errorf("NTP packet is not isomorphic:\ngot :\n%x\n\nwant :\n%x\n\n", buf.Bytes(), NTPData)
}
}
|
