forked from fatedier/frp
-
Notifications
You must be signed in to change notification settings - Fork 0
/
ports.go
180 lines (165 loc) · 3.64 KB
/
ports.go
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
package ports
import (
"errors"
"fmt"
"net"
"sync"
"time"
)
const (
MinPort = 1
MaxPort = 65535
MaxPortReservedDuration = time.Duration(24) * time.Hour
CleanReservedPortsInterval = time.Hour
)
var (
ErrPortAlreadyUsed = errors.New("port already used")
ErrPortNotAllowed = errors.New("port not allowed")
ErrPortUnAvailable = errors.New("port unavailable")
ErrNoAvailablePort = errors.New("no available port")
)
type PortCtx struct {
ProxyName string
Port int
Closed bool
UpdateTime time.Time
}
type PortManager struct {
reservedPorts map[string]*PortCtx
usedPorts map[int]*PortCtx
freePorts map[int]struct{}
bindAddr string
netType string
mu sync.Mutex
}
func NewPortManager(netType string, bindAddr string, allowPorts map[int]struct{}) *PortManager {
pm := &PortManager{
reservedPorts: make(map[string]*PortCtx),
usedPorts: make(map[int]*PortCtx),
freePorts: make(map[int]struct{}),
bindAddr: bindAddr,
netType: netType,
}
if len(allowPorts) > 0 {
for port, _ := range allowPorts {
pm.freePorts[port] = struct{}{}
}
} else {
for i := MinPort; i <= MaxPort; i++ {
pm.freePorts[i] = struct{}{}
}
}
go pm.cleanReservedPortsWorker()
return pm
}
func (pm *PortManager) Acquire(name string, port int) (realPort int, err error) {
portCtx := &PortCtx{
ProxyName: name,
Closed: false,
UpdateTime: time.Now(),
}
var ok bool
pm.mu.Lock()
defer func() {
if err == nil {
portCtx.Port = realPort
}
pm.mu.Unlock()
}()
// check reserved ports first
if port == 0 {
if ctx, ok := pm.reservedPorts[name]; ok {
if pm.isPortAvailable(ctx.Port) {
realPort = ctx.Port
pm.usedPorts[realPort] = portCtx
pm.reservedPorts[name] = portCtx
delete(pm.freePorts, realPort)
return
}
}
}
if port == 0 {
// get random port
count := 0
maxTryTimes := 5
for k, _ := range pm.freePorts {
count++
if count > maxTryTimes {
break
}
if pm.isPortAvailable(k) {
realPort = k
pm.usedPorts[realPort] = portCtx
pm.reservedPorts[name] = portCtx
delete(pm.freePorts, realPort)
break
}
}
if realPort == 0 {
err = ErrNoAvailablePort
}
} else {
// specified port
if _, ok = pm.freePorts[port]; ok {
if pm.isPortAvailable(port) {
realPort = port
pm.usedPorts[realPort] = portCtx
pm.reservedPorts[name] = portCtx
delete(pm.freePorts, realPort)
} else {
err = ErrPortUnAvailable
}
} else {
if _, ok = pm.usedPorts[port]; ok {
err = ErrPortAlreadyUsed
} else {
err = ErrPortNotAllowed
}
}
}
return
}
func (pm *PortManager) isPortAvailable(port int) bool {
if pm.netType == "udp" {
addr, err := net.ResolveUDPAddr("udp", fmt.Sprintf("%s:%d", pm.bindAddr, port))
if err != nil {
return false
}
l, err := net.ListenUDP("udp", addr)
if err != nil {
return false
}
l.Close()
return true
} else {
l, err := net.Listen(pm.netType, fmt.Sprintf("%s:%d", pm.bindAddr, port))
if err != nil {
return false
}
l.Close()
return true
}
}
func (pm *PortManager) Release(port int) {
pm.mu.Lock()
defer pm.mu.Unlock()
if ctx, ok := pm.usedPorts[port]; ok {
pm.freePorts[port] = struct{}{}
delete(pm.usedPorts, port)
ctx.Closed = true
ctx.UpdateTime = time.Now()
}
}
// Release reserved port if it isn't used in last 24 hours.
func (pm *PortManager) cleanReservedPortsWorker() {
for {
time.Sleep(CleanReservedPortsInterval)
pm.mu.Lock()
for name, ctx := range pm.reservedPorts {
if ctx.Closed && time.Since(ctx.UpdateTime) > MaxPortReservedDuration {
delete(pm.reservedPorts, name)
}
}
pm.mu.Unlock()
}
}