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
|
// Package wireguard implements a few helpers for the WireGuard protocol
package wireguard
import (
"errors"
"fmt"
"net"
"codeberg.org/eduVPN/eduvpn-common/internal/wireguard/ini"
"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
)
func availableTCPPort() (int, error) {
tcpaddr, err := net.ResolveTCPAddr("tcp", "127.0.0.1:0")
if err != nil {
return -1, err
}
ltcp, err := net.ListenTCP("tcp", tcpaddr)
if err != nil {
return -1, err
}
defer ltcp.Close()
return ltcp.Addr().(*net.TCPAddr).Port, nil
}
func availableUDPPort() (int, error) {
udpaddr, err := net.ResolveUDPAddr("udp", "127.0.0.1:0")
if err != nil {
return -1, err
}
ludp, err := net.ListenUDP("udp", udpaddr)
if err != nil {
return -1, err
}
defer ludp.Close()
return ludp.LocalAddr().(*net.UDPAddr).Port, nil
}
// Proxy is the proxyguard information
type Proxy struct {
// SourcePort is the source port of the TCP socket
SourcePort int
// ListenPort is the PORT of the udp listener
ListenPort int
// Peer is the hostname/ip:port of the WireGuard peer
Peer string
}
// Config gets a wireguard config with API config `cfg`, wg key `key` and whether to use proxyguard `proxy`
func Config(cfg string, key *wgtypes.Key, proxy bool) (string, *Proxy, error) {
// the key is nil if the client does not accept WireGuard
if key == nil {
return "", nil, errors.New("the server sent us a WireGuard profile but the client does not accept WireGuard")
}
var tcpp int
var udpp int
var err error
var udpl string
if proxy {
tcpp, err = availableTCPPort()
if err != nil {
return "", nil, err
}
udpp, err = availableUDPPort()
if err != nil {
return "", nil, err
}
udpl = fmt.Sprintf("127.0.0.1:%d", udpp)
}
rcfg, peer, err := configReplace(cfg, *key, udpl)
if err != nil {
return "", nil, err
}
var retP *Proxy
if proxy {
retP = &Proxy{
SourcePort: tcpp,
ListenPort: udpp,
Peer: peer,
}
}
return rcfg, retP, nil
}
// ConfigReplace replaces the wireguard config with our private key and proxy in case of TCP
func configReplace(cfg string, key wgtypes.Key, proxy string) (string, string, error) {
// first parse the config
secs := ini.Parse(cfg)
if secs.Empty() {
return "", "", errors.New("parsed ini is empty")
}
// find the interface section
// and set the private key
is, err := secs.Section("Interface")
if err != nil {
return "", "", err
}
is.AddOrReplaceKeyValue("PrivateKey", key.String())
peer := ""
if proxy != "" {
ps, err := secs.Section("Peer")
if err != nil {
return "", "", err
}
peer, err = ps.RemoveKey("ProxyEndpoint")
if err != nil {
return "", "", err
}
ps.AddOrReplaceKeyValue("Endpoint", proxy)
}
return secs.String(), peer, nil
}
|
