forked from fengshuai198904/goflyway
/
multiplexer.go
142 lines (112 loc) · 2.18 KB
/
multiplexer.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
package proxy
import (
"github.com/coyove/goflyway/pkg/logg"
"errors"
"io"
"net"
"time"
)
// prefetchReader can prefetch one byte from the reader before Read()
type prefetchReader struct {
src io.Reader
first byte
reseted bool
err error
timeout int
obpool *OneBytePool
}
func (ur *prefetchReader) readTimeout(buf []byte) (n int, err error) {
finish := make(chan bool, 1)
go func() {
n, err = ur.src.Read(buf)
finish <- true
}()
select {
case <-finish:
case <-time.After(time.Duration(ur.timeout) * time.Millisecond):
err = errors.New("io read timeout")
}
return
}
func (ur *prefetchReader) prefetch() (byte, error) {
buf := ur.obpool.Get()
defer ur.obpool.Free(buf)
n, err := ur.readTimeout(buf)
ur.err = err
if n == 1 {
ur.first = buf[0]
return buf[0], nil
}
return buf[0], err
}
func (ur *prefetchReader) Read(p []byte) (int, error) {
if ur.err != nil {
return 0, ur.err
}
if !ur.reseted {
p[0] = ur.first
xp := p[1:]
n, err := ur.src.Read(xp)
ur.reseted = true
return n + 1, err
}
return ur.src.Read(p)
}
type OneBytePool chan []byte
func NewOneBytePool(s int) *OneBytePool {
p := OneBytePool(make(chan []byte, s))
return &p
}
func (p *OneBytePool) Get() []byte {
select {
case buf := <-*p:
return buf
default:
return make([]byte, 1)
}
}
func (p *OneBytePool) Free(buf []byte) {
select {
case *p <- buf:
default:
}
}
type connWrapper struct {
net.Conn
sbuffer *prefetchReader
}
func (cw *connWrapper) Read(p []byte) (int, error) {
return cw.sbuffer.Read(p)
}
type listenerWrapper struct {
net.Listener
proxy *ProxyClient
httpConn connWrapper
socksConn connWrapper
obpool *OneBytePool
}
func (l *listenerWrapper) Accept() (net.Conn, error) {
CONTINUE:
c, err := l.Listener.Accept()
wrapper := &connWrapper{
Conn: c,
sbuffer: &prefetchReader{
src: c,
obpool: l.obpool,
timeout: 2000, // 2 seconds
},
}
b, err := wrapper.sbuffer.prefetch()
if err != nil {
logg.E("mux got err: ", err)
goto CONTINUE
}
switch b {
case 0x04, 0x05:
// we are accepting SOCKS4 in case it goes to the HTTP handler
go l.proxy.handleSocks(wrapper)
goto CONTINUE
default:
return wrapper, err
}
}