1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
|
/* SPDX-License-Identifier: MIT
*
* Copyright (C) 2017-2019 WireGuard LLC. All Rights Reserved.
*/
package device
import (
"bufio"
"bytes"
"encoding/binary"
"io"
"net"
"os"
"strings"
"testing"
"time"
"golang.zx2c4.com/wireguard/tun"
)
func TestTwoDevicePing(t *testing.T) {
// TODO(crawshaw): pick unused ports on localhost
cfg1 := `private_key=481eb0d8113a4a5da532d2c3e9c14b53c8454b34ab109676f6b58c2245e37b58
listen_port=53511
replace_peers=true
public_key=f70dbb6b1b92a1dde1c783b297016af3f572fef13b0abb16a2623d89a58e9725
protocol_version=1
replace_allowed_ips=true
allowed_ip=1.0.0.2/32
endpoint=127.0.0.1:53512`
tun1 := NewChannelTUN()
dev1 := NewDevice(tun1.TUN(), NewLogger(LogLevelDebug, "dev1: "))
dev1.Up()
defer dev1.Close()
if err := dev1.IpcSetOperation(bufio.NewReader(strings.NewReader(cfg1))); err != nil {
t.Fatal(err)
}
cfg2 := `private_key=98c7989b1661a0d64fd6af3502000f87716b7c4bbcf00d04fc6073aa7b539768
listen_port=53512
replace_peers=true
public_key=49e80929259cebdda4f322d6d2b1a6fad819d603acd26fd5d845e7a123036427
protocol_version=1
replace_allowed_ips=true
allowed_ip=1.0.0.1/32
endpoint=127.0.0.1:53511`
tun2 := NewChannelTUN()
dev2 := NewDevice(tun2.TUN(), NewLogger(LogLevelDebug, "dev2: "))
dev2.Up()
defer dev2.Close()
if err := dev2.IpcSetOperation(bufio.NewReader(strings.NewReader(cfg2))); err != nil {
t.Fatal(err)
}
t.Run("ping 1.0.0.1", func(t *testing.T) {
msg2to1 := ping(net.ParseIP("1.0.0.1"), net.ParseIP("1.0.0.2"))
tun2.Outbound <- msg2to1
select {
case msgRecv := <-tun1.Inbound:
if !bytes.Equal(msg2to1, msgRecv) {
t.Error("ping did not transit correctly")
}
case <-time.After(300 * time.Millisecond):
t.Error("ping did not transit")
}
})
t.Run("ping 1.0.0.2", func(t *testing.T) {
msg1to2 := ping(net.ParseIP("1.0.0.2"), net.ParseIP("1.0.0.1"))
tun1.Outbound <- msg1to2
select {
case msgRecv := <-tun2.Inbound:
if !bytes.Equal(msg1to2, msgRecv) {
t.Error("return ping did not transit correctly")
}
case <-time.After(300 * time.Millisecond):
t.Error("return ping did not transit")
}
})
}
func ping(dst, src net.IP) []byte {
localPort := uint16(1337)
seq := uint16(0)
payload := make([]byte, 4)
binary.BigEndian.PutUint16(payload[0:], localPort)
binary.BigEndian.PutUint16(payload[2:], seq)
return genICMPv4(payload, dst, src)
}
// checksum is the "internet checksum" from https://tools.ietf.org/html/rfc1071.
func checksum(buf []byte, initial uint16) uint16 {
v := uint32(initial)
for i := 0; i < len(buf)-1; i += 2 {
v += uint32(binary.BigEndian.Uint16(buf[i:]))
}
if len(buf)%2 == 1 {
v += uint32(buf[len(buf)-1]) << 8
}
for v > 0xffff {
v = (v >> 16) + (v & 0xffff)
}
return ^uint16(v)
}
func genICMPv4(payload []byte, dst, src net.IP) []byte {
const (
icmpv4ProtocolNumber = 1
icmpv4Echo = 8
icmpv4ChecksumOffset = 2
icmpv4Size = 8
ipv4Size = 20
ipv4TotalLenOffset = 2
ipv4ChecksumOffset = 10
ttl = 65
)
hdr := make([]byte, ipv4Size+icmpv4Size)
ip := hdr[0:ipv4Size]
icmpv4 := hdr[ipv4Size : ipv4Size+icmpv4Size]
// https://tools.ietf.org/html/rfc792
icmpv4[0] = icmpv4Echo // type
icmpv4[1] = 0 // code
chksum := ^checksum(icmpv4, checksum(payload, 0))
binary.BigEndian.PutUint16(icmpv4[icmpv4ChecksumOffset:], chksum)
// https://tools.ietf.org/html/rfc760 section 3.1
length := uint16(len(hdr) + len(payload))
ip[0] = (4 << 4) | (ipv4Size / 4)
binary.BigEndian.PutUint16(ip[ipv4TotalLenOffset:], length)
ip[8] = ttl
ip[9] = icmpv4ProtocolNumber
copy(ip[12:], src.To4())
copy(ip[16:], dst.To4())
chksum = ^checksum(ip[:], 0)
binary.BigEndian.PutUint16(ip[ipv4ChecksumOffset:], chksum)
var v []byte
v = append(v, hdr...)
v = append(v, payload...)
return []byte(v)
}
// TODO(crawshaw): find a reusable home for this. package devicetest?
type ChannelTUN struct {
Inbound chan []byte // incoming packets, closed on TUN close
Outbound chan []byte // outbound packets, blocks forever on TUN close
closed chan struct{}
events chan tun.Event
tun chTun
}
func NewChannelTUN() *ChannelTUN {
c := &ChannelTUN{
Inbound: make(chan []byte),
Outbound: make(chan []byte),
closed: make(chan struct{}),
events: make(chan tun.Event, 1),
}
c.tun.c = c
c.events <- tun.EventUp
return c
}
func (c *ChannelTUN) TUN() tun.Device {
return &c.tun
}
type chTun struct {
c *ChannelTUN
}
func (t *chTun) File() *os.File { return nil }
func (t *chTun) Read(data []byte, offset int) (int, error) {
select {
case <-t.c.closed:
return 0, io.EOF // TODO(crawshaw): what is the correct error value?
case msg := <-t.c.Outbound:
return copy(data[offset:], msg), nil
}
}
// Write is called by the wireguard device to deliver a packet for routing.
func (t *chTun) Write(data []byte, offset int) (int, error) {
if offset == -1 {
close(t.c.closed)
close(t.c.events)
return 0, io.EOF
}
msg := make([]byte, len(data)-offset)
copy(msg, data[offset:])
select {
case <-t.c.closed:
return 0, io.EOF // TODO(crawshaw): what is the correct error value?
case t.c.Inbound <- msg:
return len(data) - offset, nil
}
}
func (t *chTun) Flush() error { return nil }
func (t *chTun) MTU() (int, error) { return DefaultMTU, nil }
func (t *chTun) Name() (string, error) { return "loopbackTun1", nil }
func (t *chTun) Events() chan tun.Event { return t.c.events }
func (t *chTun) Close() error {
t.Write(nil, -1)
return nil
}
func assertNil(t *testing.T, err error) {
if err != nil {
t.Fatal(err)
}
}
func assertEqual(t *testing.T, a, b []byte) {
if !bytes.Equal(a, b) {
t.Fatal(a, "!=", b)
}
}
func randDevice(t *testing.T) *Device {
sk, err := newPrivateKey()
if err != nil {
t.Fatal(err)
}
tun := newDummyTUN("dummy")
logger := NewLogger(LogLevelError, "")
device := NewDevice(tun, logger)
device.SetPrivateKey(sk)
return device
}
|
