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
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
|
// Copyright (c) 2021 Tulir Asokan
//
// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at http://mozilla.org/MPL/2.0/.
package socket
import (
"context"
"errors"
"fmt"
"net/http"
"sync"
"time"
"github.com/gorilla/websocket"
waLog "go.mau.fi/whatsmeow/util/log"
)
type FrameSocket struct {
conn *websocket.Conn
ctx context.Context
cancel func()
log waLog.Logger
lock sync.Mutex
Frames chan []byte
OnDisconnect func(remote bool)
WriteTimeout time.Duration
Header []byte
incomingLength int
receivedLength int
incoming []byte
partialHeader []byte
}
func NewFrameSocket(log waLog.Logger, header []byte) *FrameSocket {
return &FrameSocket{
conn: nil,
log: log,
Header: header,
Frames: make(chan []byte),
}
}
func (fs *FrameSocket) IsConnected() bool {
return fs.conn != nil
}
func (fs *FrameSocket) Context() context.Context {
return fs.ctx
}
func (fs *FrameSocket) Close(code int) {
fs.lock.Lock()
defer fs.lock.Unlock()
if fs.conn == nil {
return
}
if code > 0 {
message := websocket.FormatCloseMessage(code, "")
err := fs.conn.WriteControl(websocket.CloseMessage, message, time.Now().Add(time.Second))
if err != nil {
fs.log.Warnf("Error sending close message: %v", err)
}
}
fs.cancel()
err := fs.conn.Close()
if err != nil {
fs.log.Errorf("Error closing websocket: %v", err)
}
fs.conn = nil
fs.ctx = nil
fs.cancel = nil
if fs.OnDisconnect != nil {
go fs.OnDisconnect(code == 0)
}
}
func (fs *FrameSocket) Connect() error {
fs.lock.Lock()
defer fs.lock.Unlock()
if fs.conn != nil {
return ErrSocketAlreadyOpen
}
ctx, cancel := context.WithCancel(context.Background())
dialer := websocket.Dialer{}
headers := http.Header{"Origin": []string{Origin}}
fs.log.Debugf("Dialing %s", URL)
conn, _, err := dialer.Dial(URL, headers)
if err != nil {
cancel()
return fmt.Errorf("couldn't dial whatsapp web websocket: %w", err)
}
fs.ctx, fs.cancel = ctx, cancel
fs.conn = conn
conn.SetCloseHandler(func(code int, text string) error {
fs.log.Debugf("Server closed websocket with status %d/%s", code, text)
cancel()
// from default CloseHandler
message := websocket.FormatCloseMessage(code, "")
_ = conn.WriteControl(websocket.CloseMessage, message, time.Now().Add(time.Second))
return nil
})
go fs.readPump(conn, ctx)
return nil
}
func (fs *FrameSocket) SendFrame(data []byte) error {
conn := fs.conn
if conn == nil {
return ErrSocketClosed
}
dataLength := len(data)
if dataLength >= FrameMaxSize {
return fmt.Errorf("%w (got %d bytes, max %d bytes)", ErrFrameTooLarge, len(data), FrameMaxSize)
}
headerLength := len(fs.Header)
// Whole frame is header + 3 bytes for length + data
wholeFrame := make([]byte, headerLength+FrameLengthSize+dataLength)
// Copy the header if it's there
if fs.Header != nil {
copy(wholeFrame[:headerLength], fs.Header)
// We only want to send the header once
fs.Header = nil
}
// Encode length of frame
wholeFrame[headerLength] = byte(dataLength >> 16)
wholeFrame[headerLength+1] = byte(dataLength >> 8)
wholeFrame[headerLength+2] = byte(dataLength)
// Copy actual frame data
copy(wholeFrame[headerLength+FrameLengthSize:], data)
if fs.WriteTimeout > 0 {
err := conn.SetWriteDeadline(time.Now().Add(fs.WriteTimeout))
if err != nil {
fs.log.Warnf("Failed to set write deadline: %v", err)
}
}
return conn.WriteMessage(websocket.BinaryMessage, wholeFrame)
}
func (fs *FrameSocket) frameComplete() {
data := fs.incoming
fs.incoming = nil
fs.partialHeader = nil
fs.incomingLength = 0
fs.receivedLength = 0
fs.Frames <- data
}
func (fs *FrameSocket) processData(msg []byte) {
for len(msg) > 0 {
// This probably doesn't happen a lot (if at all), so the code is unoptimized
if fs.partialHeader != nil {
msg = append(fs.partialHeader, msg...)
fs.partialHeader = nil
}
if fs.incoming == nil {
if len(msg) >= FrameLengthSize {
length := (int(msg[0]) << 16) + (int(msg[1]) << 8) + int(msg[2])
fs.incomingLength = length
fs.receivedLength = len(msg)
msg = msg[FrameLengthSize:]
if len(msg) >= length {
fs.incoming = msg[:length]
msg = msg[length:]
fs.frameComplete()
} else {
fs.incoming = make([]byte, length)
copy(fs.incoming, msg)
msg = nil
}
} else {
fs.log.Warnf("Received partial header (report if this happens often)")
fs.partialHeader = msg
msg = nil
}
} else {
if len(fs.incoming)+len(msg) >= fs.incomingLength {
copy(fs.incoming[fs.receivedLength:], msg[:fs.incomingLength-fs.receivedLength])
msg = msg[fs.incomingLength-fs.receivedLength:]
fs.frameComplete()
} else {
copy(fs.incoming[fs.receivedLength:], msg)
fs.receivedLength += len(msg)
msg = nil
}
}
}
}
func (fs *FrameSocket) readPump(conn *websocket.Conn, ctx context.Context) {
fs.log.Debugf("Frame websocket read pump starting %p", fs)
defer func() {
fs.log.Debugf("Frame websocket read pump exiting %p", fs)
go fs.Close(0)
}()
for {
msgType, data, err := conn.ReadMessage()
if err != nil {
// Ignore the error if the context has been closed
if !errors.Is(ctx.Err(), context.Canceled) {
fs.log.Errorf("Error reading from websocket: %v", err)
}
return
} else if msgType != websocket.BinaryMessage {
fs.log.Warnf("Got unexpected websocket message type %d", msgType)
continue
}
fs.processData(data)
}
}
|
