forked from moby/libnetwork
-
Notifications
You must be signed in to change notification settings - Fork 0
/
pipe.go
280 lines (252 loc) · 6.7 KB
/
pipe.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
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
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
package winio
import (
"errors"
"net"
"os"
"syscall"
"time"
"unsafe"
)
//sys connectNamedPipe(pipe syscall.Handle, o *syscall.Overlapped) (err error) = ConnectNamedPipe
//sys createNamedPipe(name string, flags uint32, pipeMode uint32, maxInstances uint32, outSize uint32, inSize uint32, defaultTimeout uint32, sa *securityAttributes) (handle syscall.Handle, err error) [failretval==syscall.InvalidHandle] = CreateNamedPipeW
//sys createFile(name string, access uint32, mode uint32, sa *securityAttributes, createmode uint32, attrs uint32, templatefile syscall.Handle) (handle syscall.Handle, err error) [failretval==syscall.InvalidHandle] = CreateFileW
//sys waitNamedPipe(name string, timeout uint32) (err error) = WaitNamedPipeW
type securityAttributes struct {
Length uint32
SecurityDescriptor *byte
InheritHandle uint32
}
const (
cERROR_PIPE_BUSY = syscall.Errno(231)
cERROR_PIPE_CONNECTED = syscall.Errno(535)
cERROR_SEM_TIMEOUT = syscall.Errno(121)
cPIPE_ACCESS_DUPLEX = 0x3
cFILE_FLAG_FIRST_PIPE_INSTANCE = 0x80000
cSECURITY_SQOS_PRESENT = 0x100000
cSECURITY_ANONYMOUS = 0
cPIPE_REJECT_REMOTE_CLIENTS = 0x8
cPIPE_UNLIMITED_INSTANCES = 255
cNMPWAIT_USE_DEFAULT_WAIT = 0
cNMPWAIT_NOWAIT = 1
)
var (
// This error should match net.errClosing since docker takes a dependency on its text
ErrPipeListenerClosed = errors.New("use of closed network connection")
)
type win32Pipe struct {
*win32File
path string
}
type pipeAddress string
func (f *win32Pipe) LocalAddr() net.Addr {
return pipeAddress(f.path)
}
func (f *win32Pipe) RemoteAddr() net.Addr {
return pipeAddress(f.path)
}
func (f *win32Pipe) SetDeadline(t time.Time) error {
f.SetReadDeadline(t)
f.SetWriteDeadline(t)
return nil
}
func (s pipeAddress) Network() string {
return "pipe"
}
func (s pipeAddress) String() string {
return string(s)
}
func makeWin32Pipe(h syscall.Handle, path string) (*win32Pipe, error) {
f, err := makeWin32File(h)
if err != nil {
return nil, err
}
return &win32Pipe{f, path}, nil
}
// DialPipe connects to a named pipe by path, timing out if the connection
// takes longer than the specified duration. If timeout is nil, then the timeout
// is the default timeout established by the pipe server.
func DialPipe(path string, timeout *time.Duration) (net.Conn, error) {
var absTimeout time.Time
if timeout != nil {
absTimeout = time.Now().Add(*timeout)
}
var err error
var h syscall.Handle
for {
h, err = createFile(path, syscall.GENERIC_READ|syscall.GENERIC_WRITE, 0, nil, syscall.OPEN_EXISTING, syscall.FILE_FLAG_OVERLAPPED|cSECURITY_SQOS_PRESENT|cSECURITY_ANONYMOUS, 0)
if err != cERROR_PIPE_BUSY {
break
}
now := time.Now()
var ms uint32
if absTimeout.IsZero() {
ms = cNMPWAIT_USE_DEFAULT_WAIT
} else if now.After(absTimeout) {
ms = cNMPWAIT_NOWAIT
} else {
ms = uint32(absTimeout.Sub(now).Nanoseconds() / 1000 / 1000)
}
err = waitNamedPipe(path, ms)
if err != nil {
if err == cERROR_SEM_TIMEOUT {
return nil, ErrTimeout
}
break
}
}
if err != nil {
return nil, &os.PathError{"open", path, err}
}
p, err := makeWin32Pipe(h, path)
if err != nil {
syscall.Close(h)
return nil, err
}
return p, nil
}
type acceptResponse struct {
p *win32Pipe
err error
}
type win32PipeListener struct {
firstHandle syscall.Handle
path string
securityDescriptor []byte
acceptCh chan (chan acceptResponse)
closeCh chan int
doneCh chan int
}
func makeServerPipeHandle(path string, securityDescriptor []byte, first bool) (syscall.Handle, error) {
var flags uint32 = cPIPE_ACCESS_DUPLEX | syscall.FILE_FLAG_OVERLAPPED
if first {
flags |= cFILE_FLAG_FIRST_PIPE_INSTANCE
}
var sa securityAttributes
sa.Length = uint32(unsafe.Sizeof(sa))
if securityDescriptor != nil {
sa.SecurityDescriptor = &securityDescriptor[0]
}
h, err := createNamedPipe(path, flags, cPIPE_REJECT_REMOTE_CLIENTS, cPIPE_UNLIMITED_INSTANCES, 4096, 4096, 0, &sa)
if err != nil {
return 0, &os.PathError{"open", path, err}
}
return h, nil
}
func (l *win32PipeListener) makeServerPipe() (*win32Pipe, error) {
h, err := makeServerPipeHandle(l.path, l.securityDescriptor, false)
if err != nil {
return nil, err
}
p, err := makeWin32Pipe(h, l.path)
if err != nil {
syscall.Close(h)
return nil, err
}
return p, nil
}
func (l *win32PipeListener) listenerRoutine() {
closed := false
for !closed {
select {
case <-l.closeCh:
closed = true
case responseCh := <-l.acceptCh:
p, err := l.makeServerPipe()
if err == nil {
// Wait for the client to connect.
ch := make(chan error)
go func() {
ch <- connectPipe(p)
}()
select {
case err = <-ch:
if err != nil {
p.Close()
p = nil
}
case <-l.closeCh:
// Abort the connect request by closing the handle.
p.Close()
p = nil
err = <-ch
if err == nil || err == ErrFileClosed {
err = ErrPipeListenerClosed
}
closed = true
}
}
responseCh <- acceptResponse{p, err}
}
}
syscall.Close(l.firstHandle)
l.firstHandle = 0
// Notify Close() and Accept() callers that the handle has been closed.
close(l.doneCh)
}
func ListenPipe(path, sddl string) (net.Listener, error) {
var (
sd []byte
err error
)
if sddl != "" {
sd, err = sddlToSecurityDescriptor(sddl)
if err != nil {
return nil, err
}
}
h, err := makeServerPipeHandle(path, sd, true)
if err != nil {
return nil, err
}
// Immediately open and then close a client handle so that the named pipe is
// created but not currently accepting connections.
h2, err := createFile(path, 0, 0, nil, syscall.OPEN_EXISTING, cSECURITY_SQOS_PRESENT|cSECURITY_ANONYMOUS, 0)
if err != nil {
syscall.Close(h)
return nil, err
}
syscall.Close(h2)
l := &win32PipeListener{
firstHandle: h,
path: path,
securityDescriptor: sd,
acceptCh: make(chan (chan acceptResponse)),
closeCh: make(chan int),
doneCh: make(chan int),
}
go l.listenerRoutine()
return l, nil
}
func connectPipe(p *win32Pipe) error {
c, err := p.prepareIo()
if err != nil {
return err
}
err = connectNamedPipe(p.handle, &c.o)
_, err = p.asyncIo(c, time.Time{}, 0, err)
if err != nil && err != cERROR_PIPE_CONNECTED {
return err
}
return nil
}
func (l *win32PipeListener) Accept() (net.Conn, error) {
ch := make(chan acceptResponse)
select {
case l.acceptCh <- ch:
response := <-ch
return response.p, response.err
case <-l.doneCh:
return nil, ErrPipeListenerClosed
}
}
func (l *win32PipeListener) Close() error {
select {
case l.closeCh <- 1:
<-l.doneCh
case <-l.doneCh:
}
return nil
}
func (l *win32PipeListener) Addr() net.Addr {
return pipeAddress(l.path)
}