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
|
package main
import (
"net"
"runtime"
"sync"
"sync/atomic"
"time"
)
type Device struct {
log *Logger // collection of loggers for levels
idCounter uint // for assigning debug ids to peers
fwMark uint32
tun struct {
device TUNDevice
isUp AtomicBool
mtu int32
}
pool struct {
messageBuffers sync.Pool
}
net struct {
mutex sync.RWMutex
addr *net.UDPAddr // UDP source address
conn *net.UDPConn // UDP "connection"
fwmark uint32
}
mutex sync.RWMutex
privateKey NoisePrivateKey
publicKey NoisePublicKey
routingTable RoutingTable
indices IndexTable
queue struct {
encryption chan *QueueOutboundElement
decryption chan *QueueInboundElement
handshake chan QueueHandshakeElement
}
signal struct {
stop chan struct{} // halts all go routines
newUDPConn chan struct{} // a net.conn was set (consumed by the receiver routine)
}
underLoadUntil atomic.Value
ratelimiter Ratelimiter
peers map[NoisePublicKey]*Peer
mac CookieChecker
}
/* Warning:
* The caller must hold the device mutex (write lock)
*/
func removePeerUnsafe(device *Device, key NoisePublicKey) {
peer, ok := device.peers[key]
if !ok {
return
}
peer.mutex.Lock()
device.routingTable.RemovePeer(peer)
delete(device.peers, key)
peer.Close()
}
func (device *Device) IsUnderLoad() bool {
// check if currently under load
now := time.Now()
underLoad := len(device.queue.handshake) >= UnderLoadQueueSize
if underLoad {
device.underLoadUntil.Store(now.Add(time.Second))
return true
}
// check if recently under load
until := device.underLoadUntil.Load().(time.Time)
return until.After(now)
}
func (device *Device) SetPrivateKey(sk NoisePrivateKey) error {
device.mutex.Lock()
defer device.mutex.Unlock()
// remove peers with matching public keys
publicKey := sk.publicKey()
for key, peer := range device.peers {
h := &peer.handshake
h.mutex.RLock()
if h.remoteStatic.Equals(publicKey) {
removePeerUnsafe(device, key)
}
h.mutex.RUnlock()
}
// update key material
device.privateKey = sk
device.publicKey = publicKey
device.mac.Init(publicKey)
// do DH precomputations
rmKey := device.privateKey.IsZero()
for key, peer := range device.peers {
h := &peer.handshake
h.mutex.Lock()
if rmKey {
h.precomputedStaticStatic = [NoisePublicKeySize]byte{}
} else {
h.precomputedStaticStatic = device.privateKey.sharedSecret(h.remoteStatic)
if isZero(h.precomputedStaticStatic[:]) {
removePeerUnsafe(device, key)
}
}
h.mutex.Unlock()
}
return nil
}
func (device *Device) GetMessageBuffer() *[MaxMessageSize]byte {
return device.pool.messageBuffers.Get().(*[MaxMessageSize]byte)
}
func (device *Device) PutMessageBuffer(msg *[MaxMessageSize]byte) {
device.pool.messageBuffers.Put(msg)
}
func NewDevice(tun TUNDevice, logLevel int) *Device {
device := new(Device)
device.mutex.Lock()
defer device.mutex.Unlock()
device.log = NewLogger(logLevel, "("+tun.Name()+") ")
device.peers = make(map[NoisePublicKey]*Peer)
device.tun.device = tun
device.indices.Init()
device.ratelimiter.Init()
device.routingTable.Reset()
device.underLoadUntil.Store(time.Time{})
// setup pools
device.pool.messageBuffers = sync.Pool{
New: func() interface{} {
return new([MaxMessageSize]byte)
},
}
// create queues
device.queue.handshake = make(chan QueueHandshakeElement, QueueHandshakeSize)
device.queue.encryption = make(chan *QueueOutboundElement, QueueOutboundSize)
device.queue.decryption = make(chan *QueueInboundElement, QueueInboundSize)
// prepare signals
device.signal.stop = make(chan struct{})
device.signal.newUDPConn = make(chan struct{}, 1)
// start workers
for i := 0; i < runtime.NumCPU(); i += 1 {
go device.RoutineEncryption()
go device.RoutineDecryption()
go device.RoutineHandshake()
}
go device.RoutineTUNEventReader()
go device.ratelimiter.RoutineGarbageCollector(device.signal.stop)
go device.RoutineReadFromTUN()
go device.RoutineReceiveIncomming()
return device
}
func (device *Device) LookupPeer(pk NoisePublicKey) *Peer {
device.mutex.RLock()
defer device.mutex.RUnlock()
return device.peers[pk]
}
func (device *Device) RemovePeer(key NoisePublicKey) {
device.mutex.Lock()
defer device.mutex.Unlock()
removePeerUnsafe(device, key)
}
func (device *Device) RemoveAllPeers() {
device.mutex.Lock()
defer device.mutex.Unlock()
for key, peer := range device.peers {
peer.mutex.Lock()
delete(device.peers, key)
peer.Close()
peer.mutex.Unlock()
}
}
func (device *Device) Close() {
device.RemoveAllPeers()
close(device.signal.stop)
closeUDPConn(device)
device.tun.device.Close()
}
func (device *Device) WaitChannel() chan struct{} {
return device.signal.stop
}
|