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1 | /* | |
2 | * Host Side support for RNDIS Networking Links | |
3 | * Copyright (C) 2005 by David Brownell | |
4 | * | |
5 | * This program is free software; you can redistribute it and/or modify | |
6 | * it under the terms of the GNU General Public License as published by | |
7 | * the Free Software Foundation; either version 2 of the License, or | |
8 | * (at your option) any later version. | |
9 | * | |
10 | * This program is distributed in the hope that it will be useful, | |
11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
13 | * GNU General Public License for more details. | |
14 | * | |
15 | * You should have received a copy of the GNU General Public License | |
16 | * along with this program; if not, write to the Free Software | |
17 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
18 | */ | |
19 | #include <linux/module.h> | |
20 | #include <linux/init.h> | |
21 | #include <linux/netdevice.h> | |
22 | #include <linux/etherdevice.h> | |
23 | #include <linux/ethtool.h> | |
24 | #include <linux/workqueue.h> | |
25 | #include <linux/mii.h> | |
26 | #include <linux/usb.h> | |
27 | #include <linux/usb/cdc.h> | |
28 | #include <linux/usb/usbnet.h> | |
29 | #include <linux/usb/rndis_host.h> | |
30 | ||
31 | ||
32 | /* | |
33 | * RNDIS is NDIS remoted over USB. It's a MSFT variant of CDC ACM ... of | |
34 | * course ACM was intended for modems, not Ethernet links! USB's standard | |
35 | * for Ethernet links is "CDC Ethernet", which is significantly simpler. | |
36 | * | |
37 | * NOTE that Microsoft's "RNDIS 1.0" specification is incomplete. Issues | |
38 | * include: | |
39 | * - Power management in particular relies on information that's scattered | |
40 | * through other documentation, and which is incomplete or incorrect even | |
41 | * there. | |
42 | * - There are various undocumented protocol requirements, such as the | |
43 | * need to send unused garbage in control-OUT messages. | |
44 | * - In some cases, MS-Windows will emit undocumented requests; this | |
45 | * matters more to peripheral implementations than host ones. | |
46 | * | |
47 | * Moreover there's a no-open-specs variant of RNDIS called "ActiveSync". | |
48 | * | |
49 | * For these reasons and others, ** USE OF RNDIS IS STRONGLY DISCOURAGED ** in | |
50 | * favor of such non-proprietary alternatives as CDC Ethernet or the newer (and | |
51 | * currently rare) "Ethernet Emulation Model" (EEM). | |
52 | */ | |
53 | ||
54 | /* | |
55 | * RNDIS notifications from device: command completion; "reverse" | |
56 | * keepalives; etc | |
57 | */ | |
58 | void rndis_status(struct usbnet *dev, struct urb *urb) | |
59 | { | |
60 | devdbg(dev, "rndis status urb, len %d stat %d", | |
61 | urb->actual_length, urb->status); | |
62 | // FIXME for keepalives, respond immediately (asynchronously) | |
63 | // if not an RNDIS status, do like cdc_status(dev,urb) does | |
64 | } | |
65 | EXPORT_SYMBOL_GPL(rndis_status); | |
66 | ||
67 | /* | |
68 | * RPC done RNDIS-style. Caller guarantees: | |
69 | * - message is properly byteswapped | |
70 | * - there's no other request pending | |
71 | * - buf can hold up to 1KB response (required by RNDIS spec) | |
72 | * On return, the first few entries are already byteswapped. | |
73 | * | |
74 | * Call context is likely probe(), before interface name is known, | |
75 | * which is why we won't try to use it in the diagnostics. | |
76 | */ | |
77 | int rndis_command(struct usbnet *dev, struct rndis_msg_hdr *buf) | |
78 | { | |
79 | struct cdc_state *info = (void *) &dev->data; | |
80 | int master_ifnum; | |
81 | int retval; | |
82 | unsigned count; | |
83 | __le32 rsp; | |
84 | u32 xid = 0, msg_len, request_id; | |
85 | ||
86 | /* REVISIT when this gets called from contexts other than probe() or | |
87 | * disconnect(): either serialize, or dispatch responses on xid | |
88 | */ | |
89 | ||
90 | /* Issue the request; xid is unique, don't bother byteswapping it */ | |
91 | if (likely(buf->msg_type != RNDIS_MSG_HALT | |
92 | && buf->msg_type != RNDIS_MSG_RESET)) { | |
93 | xid = dev->xid++; | |
94 | if (!xid) | |
95 | xid = dev->xid++; | |
96 | buf->request_id = (__force __le32) xid; | |
97 | } | |
98 | master_ifnum = info->control->cur_altsetting->desc.bInterfaceNumber; | |
99 | retval = usb_control_msg(dev->udev, | |
100 | usb_sndctrlpipe(dev->udev, 0), | |
101 | USB_CDC_SEND_ENCAPSULATED_COMMAND, | |
102 | USB_TYPE_CLASS | USB_RECIP_INTERFACE, | |
103 | 0, master_ifnum, | |
104 | buf, le32_to_cpu(buf->msg_len), | |
105 | RNDIS_CONTROL_TIMEOUT_MS); | |
106 | if (unlikely(retval < 0 || xid == 0)) | |
107 | return retval; | |
108 | ||
109 | // FIXME Seems like some devices discard responses when | |
110 | // we time out and cancel our "get response" requests... | |
111 | // so, this is fragile. Probably need to poll for status. | |
112 | ||
113 | /* ignore status endpoint, just poll the control channel; | |
114 | * the request probably completed immediately | |
115 | */ | |
116 | rsp = buf->msg_type | RNDIS_MSG_COMPLETION; | |
117 | for (count = 0; count < 10; count++) { | |
118 | memset(buf, 0, CONTROL_BUFFER_SIZE); | |
119 | retval = usb_control_msg(dev->udev, | |
120 | usb_rcvctrlpipe(dev->udev, 0), | |
121 | USB_CDC_GET_ENCAPSULATED_RESPONSE, | |
122 | USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE, | |
123 | 0, master_ifnum, | |
124 | buf, CONTROL_BUFFER_SIZE, | |
125 | RNDIS_CONTROL_TIMEOUT_MS); | |
126 | if (likely(retval >= 8)) { | |
127 | msg_len = le32_to_cpu(buf->msg_len); | |
128 | request_id = (__force u32) buf->request_id; | |
129 | if (likely(buf->msg_type == rsp)) { | |
130 | if (likely(request_id == xid)) { | |
131 | if (unlikely(rsp == RNDIS_MSG_RESET_C)) | |
132 | return 0; | |
133 | if (likely(RNDIS_STATUS_SUCCESS | |
134 | == buf->status)) | |
135 | return 0; | |
136 | dev_dbg(&info->control->dev, | |
137 | "rndis reply status %08x\n", | |
138 | le32_to_cpu(buf->status)); | |
139 | return -EL3RST; | |
140 | } | |
141 | dev_dbg(&info->control->dev, | |
142 | "rndis reply id %d expected %d\n", | |
143 | request_id, xid); | |
144 | /* then likely retry */ | |
145 | } else switch (buf->msg_type) { | |
146 | case RNDIS_MSG_INDICATE: { /* fault/event */ | |
147 | struct rndis_indicate *msg = (void *)buf; | |
148 | int state = 0; | |
149 | ||
150 | switch (msg->status) { | |
151 | case RNDIS_STATUS_MEDIA_CONNECT: | |
152 | state = 1; | |
153 | case RNDIS_STATUS_MEDIA_DISCONNECT: | |
154 | dev_info(&info->control->dev, | |
155 | "rndis media %sconnect\n", | |
156 | !state?"dis":""); | |
157 | if (dev->driver_info->link_change) | |
158 | dev->driver_info->link_change( | |
159 | dev, state); | |
160 | break; | |
161 | default: | |
162 | dev_info(&info->control->dev, | |
163 | "rndis indication: 0x%08x\n", | |
164 | le32_to_cpu(msg->status)); | |
165 | } | |
166 | } | |
167 | break; | |
168 | case RNDIS_MSG_KEEPALIVE: { /* ping */ | |
169 | struct rndis_keepalive_c *msg = (void *)buf; | |
170 | ||
171 | msg->msg_type = RNDIS_MSG_KEEPALIVE_C; | |
172 | msg->msg_len = ccpu2(sizeof *msg); | |
173 | msg->status = RNDIS_STATUS_SUCCESS; | |
174 | retval = usb_control_msg(dev->udev, | |
175 | usb_sndctrlpipe(dev->udev, 0), | |
176 | USB_CDC_SEND_ENCAPSULATED_COMMAND, | |
177 | USB_TYPE_CLASS | USB_RECIP_INTERFACE, | |
178 | 0, master_ifnum, | |
179 | msg, sizeof *msg, | |
180 | RNDIS_CONTROL_TIMEOUT_MS); | |
181 | if (unlikely(retval < 0)) | |
182 | dev_dbg(&info->control->dev, | |
183 | "rndis keepalive err %d\n", | |
184 | retval); | |
185 | } | |
186 | break; | |
187 | default: | |
188 | dev_dbg(&info->control->dev, | |
189 | "unexpected rndis msg %08x len %d\n", | |
190 | le32_to_cpu(buf->msg_type), msg_len); | |
191 | } | |
192 | } else { | |
193 | /* device probably issued a protocol stall; ignore */ | |
194 | dev_dbg(&info->control->dev, | |
195 | "rndis response error, code %d\n", retval); | |
196 | } | |
197 | msleep(2); | |
198 | } | |
199 | dev_dbg(&info->control->dev, "rndis response timeout\n"); | |
200 | return -ETIMEDOUT; | |
201 | } | |
202 | EXPORT_SYMBOL_GPL(rndis_command); | |
203 | ||
204 | /* | |
205 | * rndis_query: | |
206 | * | |
207 | * Performs a query for @oid along with 0 or more bytes of payload as | |
208 | * specified by @in_len. If @reply_len is not set to -1 then the reply | |
209 | * length is checked against this value, resulting in an error if it | |
210 | * doesn't match. | |
211 | * | |
212 | * NOTE: Adding a payload exactly or greater than the size of the expected | |
213 | * response payload is an evident requirement MSFT added for ActiveSync. | |
214 | * | |
215 | * The only exception is for OIDs that return a variably sized response, | |
216 | * in which case no payload should be added. This undocumented (and | |
217 | * nonsensical!) issue was found by sniffing protocol requests from the | |
218 | * ActiveSync 4.1 Windows driver. | |
219 | */ | |
220 | static int rndis_query(struct usbnet *dev, struct usb_interface *intf, | |
221 | void *buf, __le32 oid, u32 in_len, | |
222 | void **reply, int *reply_len) | |
223 | { | |
224 | int retval; | |
225 | union { | |
226 | void *buf; | |
227 | struct rndis_msg_hdr *header; | |
228 | struct rndis_query *get; | |
229 | struct rndis_query_c *get_c; | |
230 | } u; | |
231 | u32 off, len; | |
232 | ||
233 | u.buf = buf; | |
234 | ||
235 | memset(u.get, 0, sizeof *u.get + in_len); | |
236 | u.get->msg_type = RNDIS_MSG_QUERY; | |
237 | u.get->msg_len = cpu_to_le32(sizeof *u.get + in_len); | |
238 | u.get->oid = oid; | |
239 | u.get->len = cpu_to_le32(in_len); | |
240 | u.get->offset = ccpu2(20); | |
241 | ||
242 | retval = rndis_command(dev, u.header); | |
243 | if (unlikely(retval < 0)) { | |
244 | dev_err(&intf->dev, "RNDIS_MSG_QUERY(0x%08x) failed, %d\n", | |
245 | oid, retval); | |
246 | return retval; | |
247 | } | |
248 | ||
249 | off = le32_to_cpu(u.get_c->offset); | |
250 | len = le32_to_cpu(u.get_c->len); | |
251 | if (unlikely((8 + off + len) > CONTROL_BUFFER_SIZE)) | |
252 | goto response_error; | |
253 | ||
254 | if (*reply_len != -1 && len != *reply_len) | |
255 | goto response_error; | |
256 | ||
257 | *reply = (unsigned char *) &u.get_c->request_id + off; | |
258 | *reply_len = len; | |
259 | ||
260 | return retval; | |
261 | ||
262 | response_error: | |
263 | dev_err(&intf->dev, "RNDIS_MSG_QUERY(0x%08x) " | |
264 | "invalid response - off %d len %d\n", | |
265 | oid, off, len); | |
266 | return -EDOM; | |
267 | } | |
268 | ||
269 | int | |
270 | generic_rndis_bind(struct usbnet *dev, struct usb_interface *intf, int flags) | |
271 | { | |
272 | int retval; | |
273 | struct net_device *net = dev->net; | |
274 | struct cdc_state *info = (void *) &dev->data; | |
275 | union { | |
276 | void *buf; | |
277 | struct rndis_msg_hdr *header; | |
278 | struct rndis_init *init; | |
279 | struct rndis_init_c *init_c; | |
280 | struct rndis_query *get; | |
281 | struct rndis_query_c *get_c; | |
282 | struct rndis_set *set; | |
283 | struct rndis_set_c *set_c; | |
284 | struct rndis_halt *halt; | |
285 | } u; | |
286 | u32 tmp, phym_unspec; | |
287 | __le32 *phym; | |
288 | int reply_len; | |
289 | unsigned char *bp; | |
290 | ||
291 | /* we can't rely on i/o from stack working, or stack allocation */ | |
292 | u.buf = kmalloc(CONTROL_BUFFER_SIZE, GFP_KERNEL); | |
293 | if (!u.buf) | |
294 | return -ENOMEM; | |
295 | retval = usbnet_generic_cdc_bind(dev, intf); | |
296 | if (retval < 0) | |
297 | goto fail; | |
298 | ||
299 | u.init->msg_type = RNDIS_MSG_INIT; | |
300 | u.init->msg_len = ccpu2(sizeof *u.init); | |
301 | u.init->major_version = ccpu2(1); | |
302 | u.init->minor_version = ccpu2(0); | |
303 | ||
304 | /* max transfer (in spec) is 0x4000 at full speed, but for | |
305 | * TX we'll stick to one Ethernet packet plus RNDIS framing. | |
306 | * For RX we handle drivers that zero-pad to end-of-packet. | |
307 | * Don't let userspace change these settings. | |
308 | * | |
309 | * NOTE: there still seems to be wierdness here, as if we need | |
310 | * to do some more things to make sure WinCE targets accept this. | |
311 | * They default to jumbograms of 8KB or 16KB, which is absurd | |
312 | * for such low data rates and which is also more than Linux | |
313 | * can usually expect to allocate for SKB data... | |
314 | */ | |
315 | net->hard_header_len += sizeof (struct rndis_data_hdr); | |
316 | dev->hard_mtu = net->mtu + net->hard_header_len; | |
317 | ||
318 | dev->maxpacket = usb_maxpacket(dev->udev, dev->out, 1); | |
319 | if (dev->maxpacket == 0) { | |
320 | if (netif_msg_probe(dev)) | |
321 | dev_dbg(&intf->dev, "dev->maxpacket can't be 0\n"); | |
322 | retval = -EINVAL; | |
323 | goto fail_and_release; | |
324 | } | |
325 | ||
326 | dev->rx_urb_size = dev->hard_mtu + (dev->maxpacket + 1); | |
327 | dev->rx_urb_size &= ~(dev->maxpacket - 1); | |
328 | u.init->max_transfer_size = cpu_to_le32(dev->rx_urb_size); | |
329 | ||
330 | net->change_mtu = NULL; | |
331 | retval = rndis_command(dev, u.header); | |
332 | if (unlikely(retval < 0)) { | |
333 | /* it might not even be an RNDIS device!! */ | |
334 | dev_err(&intf->dev, "RNDIS init failed, %d\n", retval); | |
335 | goto fail_and_release; | |
336 | } | |
337 | tmp = le32_to_cpu(u.init_c->max_transfer_size); | |
338 | if (tmp < dev->hard_mtu) { | |
339 | if (tmp <= net->hard_header_len) { | |
340 | dev_err(&intf->dev, | |
341 | "dev can't take %u byte packets (max %u)\n", | |
342 | dev->hard_mtu, tmp); | |
343 | retval = -EINVAL; | |
344 | goto halt_fail_and_release; | |
345 | } | |
346 | dev->hard_mtu = tmp; | |
347 | net->mtu = dev->hard_mtu - net->hard_header_len; | |
348 | dev_warn(&intf->dev, | |
349 | "dev can't take %u byte packets (max %u), " | |
350 | "adjusting MTU to %u\n", | |
351 | dev->hard_mtu, tmp, net->mtu); | |
352 | } | |
353 | ||
354 | /* REVISIT: peripheral "alignment" request is ignored ... */ | |
355 | dev_dbg(&intf->dev, | |
356 | "hard mtu %u (%u from dev), rx buflen %Zu, align %d\n", | |
357 | dev->hard_mtu, tmp, dev->rx_urb_size, | |
358 | 1 << le32_to_cpu(u.init_c->packet_alignment)); | |
359 | ||
360 | /* module has some device initialization code needs to be done right | |
361 | * after RNDIS_INIT */ | |
362 | if (dev->driver_info->early_init && | |
363 | dev->driver_info->early_init(dev) != 0) | |
364 | goto halt_fail_and_release; | |
365 | ||
366 | /* Check physical medium */ | |
367 | phym = NULL; | |
368 | reply_len = sizeof *phym; | |
369 | retval = rndis_query(dev, intf, u.buf, OID_GEN_PHYSICAL_MEDIUM, | |
370 | 0, (void **) &phym, &reply_len); | |
371 | if (retval != 0 || !phym) { | |
372 | /* OID is optional so don't fail here. */ | |
373 | phym_unspec = RNDIS_PHYSICAL_MEDIUM_UNSPECIFIED; | |
374 | phym = &phym_unspec; | |
375 | } | |
376 | if ((flags & FLAG_RNDIS_PHYM_WIRELESS) && | |
377 | *phym != RNDIS_PHYSICAL_MEDIUM_WIRELESS_LAN) { | |
378 | if (netif_msg_probe(dev)) | |
379 | dev_dbg(&intf->dev, "driver requires wireless " | |
380 | "physical medium, but device is not.\n"); | |
381 | retval = -ENODEV; | |
382 | goto halt_fail_and_release; | |
383 | } | |
384 | if ((flags & FLAG_RNDIS_PHYM_NOT_WIRELESS) && | |
385 | *phym == RNDIS_PHYSICAL_MEDIUM_WIRELESS_LAN) { | |
386 | if (netif_msg_probe(dev)) | |
387 | dev_dbg(&intf->dev, "driver requires non-wireless " | |
388 | "physical medium, but device is wireless.\n"); | |
389 | retval = -ENODEV; | |
390 | goto halt_fail_and_release; | |
391 | } | |
392 | ||
393 | /* Get designated host ethernet address */ | |
394 | reply_len = ETH_ALEN; | |
395 | retval = rndis_query(dev, intf, u.buf, OID_802_3_PERMANENT_ADDRESS, | |
396 | 48, (void **) &bp, &reply_len); | |
397 | if (unlikely(retval< 0)) { | |
398 | dev_err(&intf->dev, "rndis get ethaddr, %d\n", retval); | |
399 | goto halt_fail_and_release; | |
400 | } | |
401 | memcpy(net->dev_addr, bp, ETH_ALEN); | |
402 | ||
403 | /* set a nonzero filter to enable data transfers */ | |
404 | memset(u.set, 0, sizeof *u.set); | |
405 | u.set->msg_type = RNDIS_MSG_SET; | |
406 | u.set->msg_len = ccpu2(4 + sizeof *u.set); | |
407 | u.set->oid = OID_GEN_CURRENT_PACKET_FILTER; | |
408 | u.set->len = ccpu2(4); | |
409 | u.set->offset = ccpu2((sizeof *u.set) - 8); | |
410 | *(__le32 *)(u.buf + sizeof *u.set) = RNDIS_DEFAULT_FILTER; | |
411 | ||
412 | retval = rndis_command(dev, u.header); | |
413 | if (unlikely(retval < 0)) { | |
414 | dev_err(&intf->dev, "rndis set packet filter, %d\n", retval); | |
415 | goto halt_fail_and_release; | |
416 | } | |
417 | ||
418 | retval = 0; | |
419 | ||
420 | kfree(u.buf); | |
421 | return retval; | |
422 | ||
423 | halt_fail_and_release: | |
424 | memset(u.halt, 0, sizeof *u.halt); | |
425 | u.halt->msg_type = RNDIS_MSG_HALT; | |
426 | u.halt->msg_len = ccpu2(sizeof *u.halt); | |
427 | (void) rndis_command(dev, (void *)u.halt); | |
428 | fail_and_release: | |
429 | usb_set_intfdata(info->data, NULL); | |
430 | usb_driver_release_interface(driver_of(intf), info->data); | |
431 | info->data = NULL; | |
432 | fail: | |
433 | kfree(u.buf); | |
434 | return retval; | |
435 | } | |
436 | EXPORT_SYMBOL_GPL(generic_rndis_bind); | |
437 | ||
438 | static int rndis_bind(struct usbnet *dev, struct usb_interface *intf) | |
439 | { | |
440 | return generic_rndis_bind(dev, intf, FLAG_RNDIS_PHYM_NOT_WIRELESS); | |
441 | } | |
442 | ||
443 | void rndis_unbind(struct usbnet *dev, struct usb_interface *intf) | |
444 | { | |
445 | struct rndis_halt *halt; | |
446 | ||
447 | /* try to clear any rndis state/activity (no i/o from stack!) */ | |
448 | halt = kzalloc(CONTROL_BUFFER_SIZE, GFP_KERNEL); | |
449 | if (halt) { | |
450 | halt->msg_type = RNDIS_MSG_HALT; | |
451 | halt->msg_len = ccpu2(sizeof *halt); | |
452 | (void) rndis_command(dev, (void *)halt); | |
453 | kfree(halt); | |
454 | } | |
455 | ||
456 | usbnet_cdc_unbind(dev, intf); | |
457 | } | |
458 | EXPORT_SYMBOL_GPL(rndis_unbind); | |
459 | ||
460 | /* | |
461 | * DATA -- host must not write zlps | |
462 | */ | |
463 | int rndis_rx_fixup(struct usbnet *dev, struct sk_buff *skb) | |
464 | { | |
465 | /* peripheral may have batched packets to us... */ | |
466 | while (likely(skb->len)) { | |
467 | struct rndis_data_hdr *hdr = (void *)skb->data; | |
468 | struct sk_buff *skb2; | |
469 | u32 msg_len, data_offset, data_len; | |
470 | ||
471 | msg_len = le32_to_cpu(hdr->msg_len); | |
472 | data_offset = le32_to_cpu(hdr->data_offset); | |
473 | data_len = le32_to_cpu(hdr->data_len); | |
474 | ||
475 | /* don't choke if we see oob, per-packet data, etc */ | |
476 | if (unlikely(hdr->msg_type != RNDIS_MSG_PACKET | |
477 | || skb->len < msg_len | |
478 | || (data_offset + data_len + 8) > msg_len)) { | |
479 | dev->stats.rx_frame_errors++; | |
480 | devdbg(dev, "bad rndis message %d/%d/%d/%d, len %d", | |
481 | le32_to_cpu(hdr->msg_type), | |
482 | msg_len, data_offset, data_len, skb->len); | |
483 | return 0; | |
484 | } | |
485 | skb_pull(skb, 8 + data_offset); | |
486 | ||
487 | /* at most one packet left? */ | |
488 | if (likely((data_len - skb->len) <= sizeof *hdr)) { | |
489 | skb_trim(skb, data_len); | |
490 | break; | |
491 | } | |
492 | ||
493 | /* try to return all the packets in the batch */ | |
494 | skb2 = skb_clone(skb, GFP_ATOMIC); | |
495 | if (unlikely(!skb2)) | |
496 | break; | |
497 | skb_pull(skb, msg_len - sizeof *hdr); | |
498 | skb_trim(skb2, data_len); | |
499 | usbnet_skb_return(dev, skb2); | |
500 | } | |
501 | ||
502 | /* caller will usbnet_skb_return the remaining packet */ | |
503 | return 1; | |
504 | } | |
505 | EXPORT_SYMBOL_GPL(rndis_rx_fixup); | |
506 | ||
507 | struct sk_buff * | |
508 | rndis_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags) | |
509 | { | |
510 | struct rndis_data_hdr *hdr; | |
511 | struct sk_buff *skb2; | |
512 | unsigned len = skb->len; | |
513 | ||
514 | if (likely(!skb_cloned(skb))) { | |
515 | int room = skb_headroom(skb); | |
516 | ||
517 | /* enough head room as-is? */ | |
518 | if (unlikely((sizeof *hdr) <= room)) | |
519 | goto fill; | |
520 | ||
521 | /* enough room, but needs to be readjusted? */ | |
522 | room += skb_tailroom(skb); | |
523 | if (likely((sizeof *hdr) <= room)) { | |
524 | skb->data = memmove(skb->head + sizeof *hdr, | |
525 | skb->data, len); | |
526 | skb_set_tail_pointer(skb, len); | |
527 | goto fill; | |
528 | } | |
529 | } | |
530 | ||
531 | /* create a new skb, with the correct size (and tailpad) */ | |
532 | skb2 = skb_copy_expand(skb, sizeof *hdr, 1, flags); | |
533 | dev_kfree_skb_any(skb); | |
534 | if (unlikely(!skb2)) | |
535 | return skb2; | |
536 | skb = skb2; | |
537 | ||
538 | /* fill out the RNDIS header. we won't bother trying to batch | |
539 | * packets; Linux minimizes wasted bandwidth through tx queues. | |
540 | */ | |
541 | fill: | |
542 | hdr = (void *) __skb_push(skb, sizeof *hdr); | |
543 | memset(hdr, 0, sizeof *hdr); | |
544 | hdr->msg_type = RNDIS_MSG_PACKET; | |
545 | hdr->msg_len = cpu_to_le32(skb->len); | |
546 | hdr->data_offset = ccpu2(sizeof(*hdr) - 8); | |
547 | hdr->data_len = cpu_to_le32(len); | |
548 | ||
549 | /* FIXME make the last packet always be short ... */ | |
550 | return skb; | |
551 | } | |
552 | EXPORT_SYMBOL_GPL(rndis_tx_fixup); | |
553 | ||
554 | ||
555 | static const struct driver_info rndis_info = { | |
556 | .description = "RNDIS device", | |
557 | .flags = FLAG_ETHER | FLAG_FRAMING_RN | FLAG_NO_SETINT, | |
558 | .bind = rndis_bind, | |
559 | .unbind = rndis_unbind, | |
560 | .status = rndis_status, | |
561 | .rx_fixup = rndis_rx_fixup, | |
562 | .tx_fixup = rndis_tx_fixup, | |
563 | }; | |
564 | ||
565 | #undef ccpu2 | |
566 | ||
567 | ||
568 | /*-------------------------------------------------------------------------*/ | |
569 | ||
570 | static const struct usb_device_id products [] = { | |
571 | { | |
572 | /* RNDIS is MSFT's un-official variant of CDC ACM */ | |
573 | USB_INTERFACE_INFO(USB_CLASS_COMM, 2 /* ACM */, 0x0ff), | |
574 | .driver_info = (unsigned long) &rndis_info, | |
575 | }, { | |
576 | /* "ActiveSync" is an undocumented variant of RNDIS, used in WM5 */ | |
577 | USB_INTERFACE_INFO(USB_CLASS_MISC, 1, 1), | |
578 | .driver_info = (unsigned long) &rndis_info, | |
579 | }, | |
580 | { }, // END | |
581 | }; | |
582 | MODULE_DEVICE_TABLE(usb, products); | |
583 | ||
584 | static struct usb_driver rndis_driver = { | |
585 | .name = "rndis_host", | |
586 | .id_table = products, | |
587 | .probe = usbnet_probe, | |
588 | .disconnect = usbnet_disconnect, | |
589 | .suspend = usbnet_suspend, | |
590 | .resume = usbnet_resume, | |
591 | }; | |
592 | ||
593 | static int __init rndis_init(void) | |
594 | { | |
595 | return usb_register(&rndis_driver); | |
596 | } | |
597 | module_init(rndis_init); | |
598 | ||
599 | static void __exit rndis_exit(void) | |
600 | { | |
601 | usb_deregister(&rndis_driver); | |
602 | } | |
603 | module_exit(rndis_exit); | |
604 | ||
605 | MODULE_AUTHOR("David Brownell"); | |
606 | MODULE_DESCRIPTION("USB Host side RNDIS driver"); | |
607 | MODULE_LICENSE("GPL"); |