-
Notifications
You must be signed in to change notification settings - Fork 23
/
usbip_protocol.txt
358 lines (332 loc) · 22.9 KB
/
usbip_protocol.txt
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
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
PRELIMINARY DRAFT, MAY CONTAIN MISTAKES!
28 Jun 2011
The USB/IP protocol follows a server/client architecture. The server exports the
USB devices and the clients imports them. The device driver for the exported
USB device runs on the client machine.
The client may ask for the list of the exported USB devices. To get the list the
client opens a TCP/IP connection towards the server, and sends an OP_REQ_DEVLIST
packet on top of the TCP/IP connection (so the actual OP_REQ_DEVLIST may be sent
in one or more pieces at the low level transport layer). The server sends back
the OP_REP_DEVLIST packet which lists the exported USB devices. Finally the
TCP/IP connection is closed.
virtual host controller usb host
"client" "server"
(imports USB devices) (exports USB devices)
| |
| OP_REQ_DEVLIST |
| ----------------------------------------------> |
| |
| OP_REP_DEVLIST |
| <---------------------------------------------- |
| |
Once the client knows the list of exported USB devices it may decide to use one
of them. First the client opens a TCP/IP connection towards the server and
sends an OP_REQ_IMPORT packet. The server replies with OP_REP_IMPORT. If the
import was successful the TCP/IP connection remains open and will be used
to transfer the URB traffic between the client and the server. The client may
send two types of packets: the USBIP_CMD_SUBMIT to submit an URB, and
USBIP_CMD_UNLINK to unlink a previously submitted URB. The answers of the
server may be USBIP_RET_SUBMIT and USBIP_RET_UNLINK respectively.
virtual host controller usb host
"client" "server"
(imports USB devices) (exports USB devices)
| |
| OP_REQ_IMPORT |
| ----------------------------------------------> |
| |
| OP_REP_IMPORT |
| <---------------------------------------------- |
| |
| |
| USBIP_CMD_SUBMIT(seqnum = n) |
| ----------------------------------------------> |
| |
| USBIP_RET_SUBMIT(seqnum = n) |
| <---------------------------------------------- |
| . |
| : |
| |
| USBIP_CMD_SUBMIT(seqnum = m) |
| ----------------------------------------------> |
| |
| USBIP_CMD_SUBMIT(seqnum = m+1) |
| ----------------------------------------------> |
| |
| USBIP_CMD_SUBMIT(seqnum = m+2) |
| ----------------------------------------------> |
| |
| USBIP_RET_SUBMIT(seqnum = m) |
| <---------------------------------------------- |
| |
| USBIP_CMD_SUBMIT(seqnum = m+3) |
| ----------------------------------------------> |
| |
| USBIP_RET_SUBMIT(seqnum = m+1) |
| <---------------------------------------------- |
| |
| USBIP_CMD_SUBMIT(seqnum = m+4) |
| ----------------------------------------------> |
| |
| USBIP_RET_SUBMIT(seqnum = m+2) |
| <---------------------------------------------- |
| . |
| : |
| |
| USBIP_CMD_UNLINK |
| ----------------------------------------------> |
| |
| USBIP_RET_UNLINK |
| <---------------------------------------------- |
| |
The fields are in network (big endian) byte order meaning that the most significant
byte (MSB) is stored at the lowest address.
OP_REQ_DEVLIST: Retrieve the list of exported USB devices.
Offset | Length | Value | Description
-----------+--------+------------+---------------------------------------------------
0 | 2 | 0x0100 | Binary-coded decimal USBIP version number: v1.0.0
-----------+--------+------------+---------------------------------------------------
2 | 2 | 0x8005 | Command code: Retrieve the list of exported USB
| | | devices.
-----------+--------+------------+---------------------------------------------------
4 | 4 | 0x00000000 | Status: unused, shall be set to 0
OP_REP_DEVLIST: Reply with the list of exported USB devices.
Offset | Length | Value | Description
-----------+--------+------------+---------------------------------------------------
0 | 2 | 0x0100 | Binary-coded decimal USBIP version number: v1.0.0.
-----------+--------+------------+---------------------------------------------------
2 | 2 | 0x0005 | Reply code: The list of exported USB devices.
-----------+--------+------------+---------------------------------------------------
4 | 4 | 0x00000000 | Status: 0 for OK
-----------+--------+------------+---------------------------------------------------
8 | 4 | n | Number of exported devices: 0 means no exported
| | | devices.
-----------+--------+------------+---------------------------------------------------
0x0C | | | From now on the exported n devices are described,
| | | if any. If no devices are exported the message
| | | ends with the previous "number of exported
| | | devices" field.
-----------+--------+------------+---------------------------------------------------
| 256 | | path: Path of the device on the host exporting the
| | | USB device, string closed with zero byte, e.g.
| | | "/sys/devices/pci0000:00/0000:00:1d.1/usb3/3-2"
| | | The unused bytes shall be filled with zero
| | | bytes.
-----------+--------+------------+---------------------------------------------------
0x10C | 32 | | busid: Bus ID of the exported device, string
| | | closed with zero byte, e.g. "3-2". The unused
| | | bytes shall be filled with zero bytes.
-----------+--------+------------+---------------------------------------------------
0x12C | 4 | | busnum
-----------+--------+------------+---------------------------------------------------
0x130 | 4 | | devnum
-----------+--------+------------+---------------------------------------------------
0x134 | 4 | | speed
-----------+--------+------------+---------------------------------------------------
0x138 | 2 | | idVendor
-----------+--------+------------+---------------------------------------------------
0x13A | 2 | | idProduct
-----------+--------+------------+---------------------------------------------------
0x13C | 2 | | bcdDevice
-----------+--------+------------+---------------------------------------------------
0x13E | 1 | | bDeviceClass
-----------+--------+------------+---------------------------------------------------
0x13F | 1 | | bDeviceSubClass
-----------+--------+------------+---------------------------------------------------
0x140 | 1 | | bDeviceProtocol
-----------+--------+------------+---------------------------------------------------
0x141 | 1 | | bConfigurationValue
-----------+--------+------------+---------------------------------------------------
0x142 | 1 | | bNumConfigurations
-----------+--------+------------+---------------------------------------------------
0x143 | 1 | | bNumInterfaces
-----------+--------+------------+---------------------------------------------------
0x144 | | m_0 | From now on each interface is described, all
| | | together bNumInterfaces times, with the
| | | the following 4 fields:
-----------+--------+------------+---------------------------------------------------
| 1 | | bInterfaceClass
-----------+--------+------------+---------------------------------------------------
0x145 | 1 | | bInterfaceSubClass
-----------+--------+------------+---------------------------------------------------
0x146 | 1 | | bInterfaceProtocol
-----------+--------+------------+---------------------------------------------------
0x147 | 1 | | padding byte for alignment, shall be set to zero
-----------+--------+------------+---------------------------------------------------
0xC + | | | The second exported USB device starts at i=1
i*0x138 + | | | with the busid field.
m_(i-1)*4 | | |
OP_REQ_IMPORT: Request to import (attach) a remote USB device.
Offset | Length | Value | Description
-----------+--------+------------+---------------------------------------------------
0 | 2 | 0x0100 | Binary-coded decimal USBIP version number: v1.0.0
-----------+--------+------------+---------------------------------------------------
2 | 2 | 0x8003 | Command code: import a remote USB device.
-----------+--------+------------+---------------------------------------------------
4 | 4 | 0x00000000 | Status: unused, shall be set to 0
-----------+--------+------------+---------------------------------------------------
8 | 32 | | busid: the busid of the exported device on the
| | | remote host. The possible values are taken
| | | from the message field OP_REP_DEVLIST.busid.
| | | A string closed with zero, the unused bytes
| | | shall be filled with zeros.
-----------+--------+------------+---------------------------------------------------
OP_REP_IMPORT: Reply to import (attach) a remote USB device.
Offset | Length | Value | Description
-----------+--------+------------+---------------------------------------------------
0 | 2 | 0x0100 | Binary-coded decimal USBIP version number: v1.0.0
-----------+--------+------------+---------------------------------------------------
2 | 2 | 0x0003 | Reply code: Reply to import.
-----------+--------+------------+---------------------------------------------------
4 | 4 | 0x00000000 | Status: 0 for OK
| | | 1 for error
-----------+--------+------------+---------------------------------------------------
8 | | | From now on comes the details of the imported
| | | device, if the previous status field was OK (0),
| | | otherwise the reply ends with the status field.
-----------+--------+------------+---------------------------------------------------
| 256 | | path: Path of the device on the host exporting the
| | | USB device, string closed with zero byte, e.g.
| | | "/sys/devices/pci0000:00/0000:00:1d.1/usb3/3-2"
| | | The unused bytes shall be filled with zero
| | | bytes.
-----------+--------+------------+---------------------------------------------------
0x108 | 32 | | busid: Bus ID of the exported device, string
| | | closed with zero byte, e.g. "3-2". The unused
| | | bytes shall be filled with zero bytes.
-----------+--------+------------+---------------------------------------------------
0x128 | 4 | | busnum
-----------+--------+------------+---------------------------------------------------
0x12C | 4 | | devnum
-----------+--------+------------+---------------------------------------------------
0x130 | 4 | | speed
-----------+--------+------------+---------------------------------------------------
0x134 | 2 | | idVendor
-----------+--------+------------+---------------------------------------------------
0x136 | 2 | | idProduct
-----------+--------+------------+---------------------------------------------------
0x138 | 2 | | bcdDevice
-----------+--------+------------+---------------------------------------------------
0x139 | 1 | | bDeviceClass
-----------+--------+------------+---------------------------------------------------
0x13A | 1 | | bDeviceSubClass
-----------+--------+------------+---------------------------------------------------
0x13B | 1 | | bDeviceProtocol
-----------+--------+------------+---------------------------------------------------
0x13C | 1 | | bConfigurationValue
-----------+--------+------------+---------------------------------------------------
0x13D | 1 | | bNumConfigurations
-----------+--------+------------+---------------------------------------------------
0x13E | 1 | | bNumInterfaces
USBIP_CMD_SUBMIT: Submit an URB
Offset | Length | Value | Description
-----------+--------+------------+---------------------------------------------------
0 | 4 | 0x00000001 | command: Submit an URB
-----------+--------+------------+---------------------------------------------------
4 | 4 | | seqnum: the sequence number of the URB to submit
-----------+--------+------------+---------------------------------------------------
8 | 4 | | devid
-----------+--------+------------+---------------------------------------------------
0xC | 4 | | direction: 0: USBIP_DIR_OUT
| | | 1: USBIP_DIR_IN
-----------+--------+------------+---------------------------------------------------
0x10 | 4 | | ep: endpoint number, possible values are: 0...15
-----------+--------+------------+---------------------------------------------------
0x14 | 4 | | transfer_flags: possible values depend on the
| | | URB transfer type, see below
-----------+--------+------------+---------------------------------------------------
0x18 | 4 | | transfer_buffer_length
-----------+--------+------------+---------------------------------------------------
0x1C | 4 | | start_frame: specify the selected frame to
| | | transmit an ISO frame, ignored if URB_ISO_ASAP
| | | is specified at transfer_flags
-----------+--------+------------+---------------------------------------------------
0x20 | 4 | | number_of_packets: number of ISO packets
-----------+--------+------------+---------------------------------------------------
0x24 | 4 | | interval: maximum time for the request on the
| | | server-side host controller
-----------+--------+------------+---------------------------------------------------
0x28 | 8 | | setup: data bytes for USB setup, filled with
| | | zeros if not used
-----------+--------+------------+---------------------------------------------------
0x30 | | | URB data. For ISO transfers the padding between
| | | each ISO packets is not transmitted.
Allowed transfer_flags | value | control | interrupt | bulk | isochronous
-------------------------+------------+---------+-----------+----------+-------------
URB_SHORT_NOT_OK | 0x00000001 | only in | only in | only in | no
URB_ISO_ASAP | 0x00000002 | no | no | no | yes
URB_NO_TRANSFER_DMA_MAP | 0x00000004 | yes | yes | yes | yes
URB_NO_FSBR | 0x00000020 | yes | no | no | no
URB_ZERO_PACKET | 0x00000040 | no | no | only out | no
URB_NO_INTERRUPT | 0x00000080 | yes | yes | yes | yes
URB_FREE_BUFFER | 0x00000100 | yes | yes | yes | yes
URB_DIR_MASK | 0x00000200 | yes | yes | yes | yes
USBIP_RET_SUBMIT: Reply for submitting an URB
Offset | Length | Value | Description
-----------+--------+------------+---------------------------------------------------
0 | 4 | 0x00000003 | command
-----------+--------+------------+---------------------------------------------------
4 | 4 | | seqnum: URB sequence number
-----------+--------+------------+---------------------------------------------------
8 | 4 | | devid
-----------+--------+------------+---------------------------------------------------
0xC | 4 | | direction: 0: USBIP_DIR_OUT
| | | 1: USBIP_DIR_IN
-----------+--------+------------+---------------------------------------------------
0x10 | 4 | | ep: endpoint number
-----------+--------+------------+---------------------------------------------------
0x14 | 4 | | status: zero for successful URB transaction,
| | | otherwise some kind of error happened.
-----------+--------+------------+---------------------------------------------------
0x18 | 4 | n | actual_length: number of URB data bytes
-----------+--------+------------+---------------------------------------------------
0x1C | 4 | | start_frame: for an ISO frame the actually
| | | selected frame for transmit.
-----------+--------+------------+---------------------------------------------------
0x20 | 4 | | number_of_packets
-----------+--------+------------+---------------------------------------------------
0x24 | 4 | | error_count
-----------+--------+------------+---------------------------------------------------
0x28 | 8 | | setup: data bytes for USB setup, filled with
| | | zeros if not used
-----------+--------+------------+---------------------------------------------------
0x30 | n | | URB data bytes. For ISO transfers the padding
| | | between each ISO packets is not transmitted.
USBIP_CMD_UNLINK: Unlink an URB
Offset | Length | Value | Description
-----------+--------+------------+---------------------------------------------------
0 | 4 | 0x00000002 | command: URB unlink command
-----------+--------+------------+---------------------------------------------------
4 | 4 | | seqnum: URB sequence number to unlink: FIXME: is this so?
-----------+--------+------------+---------------------------------------------------
8 | 4 | | devid
-----------+--------+------------+---------------------------------------------------
0xC | 4 | | direction: 0: USBIP_DIR_OUT
| | | 1: USBIP_DIR_IN
-----------+--------+------------+---------------------------------------------------
0x10 | 4 | | ep: endpoint number: zero
-----------+--------+------------+---------------------------------------------------
0x14 | 4 | | seqnum: the URB sequence number given previously
| | | at USBIP_CMD_SUBMIT.seqnum field
-----------+--------+------------+---------------------------------------------------
0x30 | n | | URB data bytes. For ISO transfers the padding
| | | between each ISO packets is not transmitted.
USBIP_RET_UNLINK: Reply for URB unlink
Offset | Length | Value | Description
-----------+--------+------------+---------------------------------------------------
0 | 4 | 0x00000004 | command: reply for the URB unlink command
-----------+--------+------------+---------------------------------------------------
4 | 4 | | seqnum: the unlinked URB sequence number
-----------+--------+------------+---------------------------------------------------
8 | 4 | | devid
-----------+--------+------------+---------------------------------------------------
0xC | 4 | | direction: 0: USBIP_DIR_OUT
| | | 1: USBIP_DIR_IN
-----------+--------+------------+---------------------------------------------------
0x10 | 4 | | ep: endpoint number
-----------+--------+------------+---------------------------------------------------
0x14 | 4 | | status: This is the value contained in the
| | | urb->status in the URB completition handler.
| | | FIXME: a better explanation needed.
-----------+--------+------------+---------------------------------------------------
0x30 | n | | URB data bytes. For ISO transfers the padding
| | | between each ISO packets is not transmitted.