-
Notifications
You must be signed in to change notification settings - Fork 5
/
client.go
172 lines (152 loc) · 4.79 KB
/
client.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
package server
import (
"io"
"net"
"time"
"github.com/dgrijalva/jwt-go"
"github.com/fatih/color"
protocol "github.com/gjbae1212/grpc-vpn/grpc/go"
"github.com/gjbae1212/grpc-vpn/internal"
"github.com/pkg/errors"
"github.com/songgao/water/waterutil"
"go.uber.org/atomic"
)
const (
queueSizeForClientIn = 1000
)
type client struct {
user string // user
originIP net.IP // user origin ip
vpnIP net.IP // user vpn ip
jwt *jwt.Token // user jwt token
stream protocol.VPN_ExchangeServer // stream
loop *atomic.Bool // whether break loop or not
exit chan bool // exit
out chan *protocol.IPPacket // out queue
in chan *protocol.IPPacket // in queue
}
// read packet
func (c *client) processReading() {
ReadLoop:
for c.loop.Load() {
packet, err := c.stream.Recv()
if err == io.EOF {
defaultLogger.Error(color.RedString("[ERR] %s (%s, %s) EOF",
c.user, c.originIP.String(), c.vpnIP.String()))
break ReadLoop
}
if err != nil {
defaultLogger.Error(color.RedString("[ERR] %s (%s, %s) %s",
c.user, c.originIP.String(), c.vpnIP.String(), err.Error()))
break ReadLoop
}
// check error code
switch packet.ErrorCode {
case protocol.ErrorCode_EC_SUCCESS:
default:
// send unknown packet
c.stream.Send(&protocol.IPPacket{ErrorCode: protocol.ErrorCode_EC_UNKNOWN})
defaultLogger.Error(color.RedString("[ERR] %s (%s, %s) %s",
c.user, c.originIP.String(), c.vpnIP.String(), internal.ErrorReceiveUnknownPacket.Error()))
break ReadLoop
}
// check packet type
switch packet.PacketType {
case protocol.IPPacketType_IPPT_RAW:
default:
defaultLogger.Error(color.RedString("[ERR] %s (%s, %s) %s",
c.user, c.originIP.String(), c.vpnIP.String(), internal.ErrorReceiveUnknownPacket.Error()))
break ReadLoop
}
// check packet
raw := packet.Packet1
if raw == nil {
defaultLogger.Error(color.RedString("[ERR] %s (%s, %s) %s",
c.user, c.originIP.String(), c.vpnIP.String(), internal.ErrorReceiveUnknownPacket.Error()))
break ReadLoop
}
// check source ip(equals vpn ip)
srcIP := waterutil.IPv4Source(raw.Raw)
if !srcIP.Equal(c.vpnIP) {
defaultLogger.Error(color.RedString("[ERR] %s (%s, %s) %s(%s)",
c.user, c.originIP.String(), c.vpnIP.String(), internal.ErrorReceiveUnknownPacket.Error(), srcIP))
break ReadLoop
}
// out to server
c.out <- packet
}
// flag off
c.loop.Store(false)
// writing exit
c.exit <- true
}
// write packet
func (c *client) processWriting() {
// make jwt checker
jwtChecker := time.NewTicker(5 * time.Minute)
WriteLoop:
for c.loop.Load() {
select {
case packet := <-c.in:
if err := c.stream.Send(packet); err != nil {
defaultLogger.Error(color.RedString("[ERR] %s (%s, %s) %s",
c.user, c.originIP.String(), c.vpnIP.String(), err.Error()))
break WriteLoop
}
case <-c.exit:
defaultLogger.Error(color.RedString("[ERR] %s (%s, %s) exit signal",
c.user, c.originIP.String(), c.vpnIP.String()))
break WriteLoop
case <-jwtChecker.C:
// if JWT is expired, sending to error and break.
if c.jwt.Claims.Valid() != nil {
defaultLogger.Error(color.RedString("[ERR] %s (%s, %s) expired JWT",
c.user, c.originIP.String(), c.vpnIP.String()))
packet := &protocol.IPPacket{
ErrorCode: protocol.ErrorCode_EC_EXPIRED_JWT,
PacketType: protocol.IPPacketType_IPPT_UNKNOWN,
}
if err := c.stream.Send(packet); err != nil {
defaultLogger.Error(color.RedString("[ERR] %s (%s, %s) %s",
c.user, c.originIP.String(), c.vpnIP.String(), err.Error()))
}
break WriteLoop
}
}
}
// stop jwt checker
jwtChecker.Stop()
// flag off
c.loop.Store(false)
}
// hasVpnIP is to check whether to be assigned vpn ip in client or not.
func (c *client) hasVpnIP() bool {
return c.vpnIP != nil
}
// newClient is to create new client.
func newClient(stream protocol.VPN_ExchangeServer, clientToServer chan *protocol.IPPacket) (*client, error) {
if stream == nil {
return nil, errors.Wrapf(internal.ErrorInvalidParams, "Method: newClient")
}
// extract params
ctx := stream.Context()
ip := ctx.Value(ipCtxName)
if ip == nil {
return nil, errors.Wrapf(internal.ErrorInvalidContext, "Method: newClient")
}
j := ctx.Value(jwtCtxName)
if j == nil {
return nil, errors.Wrapf(internal.ErrorInvalidContext, "Method: newClient")
}
c := &client{
user: j.(*jwt.Token).Claims.(*jwt.StandardClaims).Audience,
originIP: ip.(net.IP),
jwt: j.(*jwt.Token),
stream: stream,
loop: atomic.NewBool(true),
exit: make(chan bool, 1),
out: clientToServer, // vpn server queue
in: make(chan *protocol.IPPacket, queueSizeForClientIn), // only exclusive client queue
}
return c, nil
}