blob: d2fb708d8e72b8ac6e988477956cfa52eb4de2af (
plain)
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
|
/* SPDX-License-Identifier: GPL-2.0
*
* Copyright (C) 2017-2018 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
* Copyright (C) 2017-2018 Mathias N. Hall-Andersen <mathias@hall-andersen.dk>.
*/
package main
import (
"os"
"sync/atomic"
)
const DefaultMTU = 1420
type TUNEvent int
const (
TUNEventUp = 1 << iota
TUNEventDown
TUNEventMTUUpdate
)
type TUNDevice interface {
File() *os.File // returns the file descriptor of the device
Read([]byte, int) (int, error) // read a packet from the device (without any additional headers)
Write([]byte, int) (int, error) // writes a packet to the device (without any additional headers)
MTU() (int, error) // returns the MTU of the device
Name() (string, error) // fetches and returns the current name
Events() chan TUNEvent // returns a constant channel of events related to the device
Close() error // stops the device and closes the event channel
}
func (device *Device) RoutineTUNEventReader() {
setUp := false
logDebug := device.log.Debug
logInfo := device.log.Info
logError := device.log.Error
logDebug.Println("Routine: event worker - started")
device.state.starting.Done()
for event := range device.tun.device.Events() {
if event&TUNEventMTUUpdate != 0 {
mtu, err := device.tun.device.MTU()
old := atomic.LoadInt32(&device.tun.mtu)
if err != nil {
logError.Println("Failed to load updated MTU of device:", err)
} else if int(old) != mtu {
if mtu+MessageTransportSize > MaxMessageSize {
logInfo.Println("MTU updated:", mtu, "(too large)")
} else {
logInfo.Println("MTU updated:", mtu)
}
atomic.StoreInt32(&device.tun.mtu, int32(mtu))
}
}
if event&TUNEventUp != 0 && !setUp {
logInfo.Println("Interface set up")
setUp = true
device.Up()
}
if event&TUNEventDown != 0 && setUp {
logInfo.Println("Interface set down")
setUp = false
device.Down()
}
}
logDebug.Println("Routine: event worker - stopped")
device.state.stopping.Done()
}
|
