2 * Host Side support for RNDIS Networking Links
3 * Copyright (C) 2005 by David Brownell
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.
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.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, see <http://www.gnu.org/licenses/>.
18 #include <linux/module.h>
19 #include <linux/netdevice.h>
20 #include <linux/etherdevice.h>
21 #include <linux/ethtool.h>
22 #include <linux/workqueue.h>
23 #include <linux/slab.h>
24 #include <linux/mii.h>
25 #include <linux/usb.h>
26 #include <linux/usb/cdc.h>
27 #include <linux/usb/usbnet.h>
28 #include <linux/usb/rndis_host.h>
32 * RNDIS is NDIS remoted over USB. It's a MSFT variant of CDC ACM ... of
33 * course ACM was intended for modems, not Ethernet links! USB's standard
34 * for Ethernet links is "CDC Ethernet", which is significantly simpler.
36 * NOTE that Microsoft's "RNDIS 1.0" specification is incomplete. Issues
38 * - Power management in particular relies on information that's scattered
39 * through other documentation, and which is incomplete or incorrect even
41 * - There are various undocumented protocol requirements, such as the
42 * need to send unused garbage in control-OUT messages.
43 * - In some cases, MS-Windows will emit undocumented requests; this
44 * matters more to peripheral implementations than host ones.
46 * Moreover there's a no-open-specs variant of RNDIS called "ActiveSync".
48 * For these reasons and others, ** USE OF RNDIS IS STRONGLY DISCOURAGED ** in
49 * favor of such non-proprietary alternatives as CDC Ethernet or the newer (and
50 * currently rare) "Ethernet Emulation Model" (EEM).
54 * RNDIS notifications from device: command completion; "reverse"
57 void rndis_status(struct usbnet *dev, struct urb *urb)
59 netdev_dbg(dev->net, "rndis status urb, len %d stat %d\n",
60 urb->actual_length, urb->status);
61 // FIXME for keepalives, respond immediately (asynchronously)
62 // if not an RNDIS status, do like cdc_status(dev,urb) does
64 EXPORT_SYMBOL_GPL(rndis_status);
67 * RNDIS indicate messages.
69 static void rndis_msg_indicate(struct usbnet *dev, struct rndis_indicate *msg,
72 struct cdc_state *info = (void *)&dev->data;
73 struct device *udev = &info->control->dev;
75 if (dev->driver_info->indication) {
76 dev->driver_info->indication(dev, msg, buflen);
78 u32 status = le32_to_cpu(msg->status);
81 case RNDIS_STATUS_MEDIA_CONNECT:
82 dev_info(udev, "rndis media connect\n");
84 case RNDIS_STATUS_MEDIA_DISCONNECT:
85 dev_info(udev, "rndis media disconnect\n");
88 dev_info(udev, "rndis indication: 0x%08x\n", status);
94 * RPC done RNDIS-style. Caller guarantees:
95 * - message is properly byteswapped
96 * - there's no other request pending
97 * - buf can hold up to 1KB response (required by RNDIS spec)
98 * On return, the first few entries are already byteswapped.
100 * Call context is likely probe(), before interface name is known,
101 * which is why we won't try to use it in the diagnostics.
103 int rndis_command(struct usbnet *dev, struct rndis_msg_hdr *buf, int buflen)
105 struct cdc_state *info = (void *) &dev->data;
106 struct usb_cdc_notification notification;
111 u32 xid = 0, msg_len, request_id, msg_type, rsp,
114 /* REVISIT when this gets called from contexts other than probe() or
115 * disconnect(): either serialize, or dispatch responses on xid
118 msg_type = le32_to_cpu(buf->msg_type);
120 /* Issue the request; xid is unique, don't bother byteswapping it */
121 if (likely(msg_type != RNDIS_MSG_HALT && msg_type != RNDIS_MSG_RESET)) {
125 buf->request_id = (__force __le32) xid;
127 master_ifnum = info->control->cur_altsetting->desc.bInterfaceNumber;
128 retval = usb_control_msg(dev->udev,
129 usb_sndctrlpipe(dev->udev, 0),
130 USB_CDC_SEND_ENCAPSULATED_COMMAND,
131 USB_TYPE_CLASS | USB_RECIP_INTERFACE,
133 buf, le32_to_cpu(buf->msg_len),
134 RNDIS_CONTROL_TIMEOUT_MS);
135 if (unlikely(retval < 0 || xid == 0))
138 /* Some devices don't respond on the control channel until
139 * polled on the status channel, so do that first. */
140 if (dev->driver_info->data & RNDIS_DRIVER_DATA_POLL_STATUS) {
141 retval = usb_interrupt_msg(
143 usb_rcvintpipe(dev->udev,
144 dev->status->desc.bEndpointAddress),
145 ¬ification, sizeof(notification), &partial,
146 RNDIS_CONTROL_TIMEOUT_MS);
147 if (unlikely(retval < 0))
151 /* Poll the control channel; the request probably completed immediately */
152 rsp = le32_to_cpu(buf->msg_type) | RNDIS_MSG_COMPLETION;
153 for (count = 0; count < 10; count++) {
154 memset(buf, 0, CONTROL_BUFFER_SIZE);
155 retval = usb_control_msg(dev->udev,
156 usb_rcvctrlpipe(dev->udev, 0),
157 USB_CDC_GET_ENCAPSULATED_RESPONSE,
158 USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
161 RNDIS_CONTROL_TIMEOUT_MS);
162 if (likely(retval >= 8)) {
163 msg_type = le32_to_cpu(buf->msg_type);
164 msg_len = le32_to_cpu(buf->msg_len);
165 status = le32_to_cpu(buf->status);
166 request_id = (__force u32) buf->request_id;
167 if (likely(msg_type == rsp)) {
168 if (likely(request_id == xid)) {
169 if (unlikely(rsp == RNDIS_MSG_RESET_C))
171 if (likely(RNDIS_STATUS_SUCCESS ==
174 dev_dbg(&info->control->dev,
175 "rndis reply status %08x\n",
179 dev_dbg(&info->control->dev,
180 "rndis reply id %d expected %d\n",
182 /* then likely retry */
183 } else switch (msg_type) {
184 case RNDIS_MSG_INDICATE: /* fault/event */
185 rndis_msg_indicate(dev, (void *)buf, buflen);
187 case RNDIS_MSG_KEEPALIVE: { /* ping */
188 struct rndis_keepalive_c *msg = (void *)buf;
190 msg->msg_type = cpu_to_le32(RNDIS_MSG_KEEPALIVE_C);
191 msg->msg_len = cpu_to_le32(sizeof *msg);
192 msg->status = cpu_to_le32(RNDIS_STATUS_SUCCESS);
193 retval = usb_control_msg(dev->udev,
194 usb_sndctrlpipe(dev->udev, 0),
195 USB_CDC_SEND_ENCAPSULATED_COMMAND,
196 USB_TYPE_CLASS | USB_RECIP_INTERFACE,
199 RNDIS_CONTROL_TIMEOUT_MS);
200 if (unlikely(retval < 0))
201 dev_dbg(&info->control->dev,
202 "rndis keepalive err %d\n",
207 dev_dbg(&info->control->dev,
208 "unexpected rndis msg %08x len %d\n",
209 le32_to_cpu(buf->msg_type), msg_len);
212 /* device probably issued a protocol stall; ignore */
213 dev_dbg(&info->control->dev,
214 "rndis response error, code %d\n", retval);
218 dev_dbg(&info->control->dev, "rndis response timeout\n");
221 EXPORT_SYMBOL_GPL(rndis_command);
226 * Performs a query for @oid along with 0 or more bytes of payload as
227 * specified by @in_len. If @reply_len is not set to -1 then the reply
228 * length is checked against this value, resulting in an error if it
231 * NOTE: Adding a payload exactly or greater than the size of the expected
232 * response payload is an evident requirement MSFT added for ActiveSync.
234 * The only exception is for OIDs that return a variably sized response,
235 * in which case no payload should be added. This undocumented (and
236 * nonsensical!) issue was found by sniffing protocol requests from the
237 * ActiveSync 4.1 Windows driver.
239 static int rndis_query(struct usbnet *dev, struct usb_interface *intf,
240 void *buf, u32 oid, u32 in_len,
241 void **reply, int *reply_len)
246 struct rndis_msg_hdr *header;
247 struct rndis_query *get;
248 struct rndis_query_c *get_c;
254 memset(u.get, 0, sizeof *u.get + in_len);
255 u.get->msg_type = cpu_to_le32(RNDIS_MSG_QUERY);
256 u.get->msg_len = cpu_to_le32(sizeof *u.get + in_len);
257 u.get->oid = cpu_to_le32(oid);
258 u.get->len = cpu_to_le32(in_len);
259 u.get->offset = cpu_to_le32(20);
261 retval = rndis_command(dev, u.header, CONTROL_BUFFER_SIZE);
262 if (unlikely(retval < 0)) {
263 dev_err(&intf->dev, "RNDIS_MSG_QUERY(0x%08x) failed, %d\n",
268 off = le32_to_cpu(u.get_c->offset);
269 len = le32_to_cpu(u.get_c->len);
270 if (unlikely((off > CONTROL_BUFFER_SIZE - 8) ||
271 (len > CONTROL_BUFFER_SIZE - 8 - off)))
274 if (*reply_len != -1 && len != *reply_len)
277 *reply = (unsigned char *) &u.get_c->request_id + off;
283 dev_err(&intf->dev, "RNDIS_MSG_QUERY(0x%08x) "
284 "invalid response - off %d len %d\n",
289 /* same as usbnet_netdev_ops but MTU change not allowed */
290 static const struct net_device_ops rndis_netdev_ops = {
291 .ndo_open = usbnet_open,
292 .ndo_stop = usbnet_stop,
293 .ndo_start_xmit = usbnet_start_xmit,
294 .ndo_tx_timeout = usbnet_tx_timeout,
295 .ndo_get_stats64 = usbnet_get_stats64,
296 .ndo_set_mac_address = eth_mac_addr,
297 .ndo_validate_addr = eth_validate_addr,
301 generic_rndis_bind(struct usbnet *dev, struct usb_interface *intf, int flags)
304 struct net_device *net = dev->net;
305 struct cdc_state *info = (void *) &dev->data;
308 struct rndis_msg_hdr *header;
309 struct rndis_init *init;
310 struct rndis_init_c *init_c;
311 struct rndis_query *get;
312 struct rndis_query_c *get_c;
313 struct rndis_set *set;
314 struct rndis_set_c *set_c;
315 struct rndis_halt *halt;
318 __le32 phym_unspec, *phym;
322 /* we can't rely on i/o from stack working, or stack allocation */
323 u.buf = kmalloc(CONTROL_BUFFER_SIZE, GFP_KERNEL);
326 retval = usbnet_generic_cdc_bind(dev, intf);
330 u.init->msg_type = cpu_to_le32(RNDIS_MSG_INIT);
331 u.init->msg_len = cpu_to_le32(sizeof *u.init);
332 u.init->major_version = cpu_to_le32(1);
333 u.init->minor_version = cpu_to_le32(0);
335 /* max transfer (in spec) is 0x4000 at full speed, but for
336 * TX we'll stick to one Ethernet packet plus RNDIS framing.
337 * For RX we handle drivers that zero-pad to end-of-packet.
338 * Don't let userspace change these settings.
340 * NOTE: there still seems to be wierdness here, as if we need
341 * to do some more things to make sure WinCE targets accept this.
342 * They default to jumbograms of 8KB or 16KB, which is absurd
343 * for such low data rates and which is also more than Linux
344 * can usually expect to allocate for SKB data...
346 net->hard_header_len += sizeof (struct rndis_data_hdr);
347 dev->hard_mtu = net->mtu + net->hard_header_len;
349 dev->maxpacket = usb_maxpacket(dev->udev, dev->out, 1);
350 if (dev->maxpacket == 0) {
351 netif_dbg(dev, probe, dev->net,
352 "dev->maxpacket can't be 0\n");
354 goto fail_and_release;
357 dev->rx_urb_size = dev->hard_mtu + (dev->maxpacket + 1);
358 dev->rx_urb_size &= ~(dev->maxpacket - 1);
359 u.init->max_transfer_size = cpu_to_le32(dev->rx_urb_size);
361 net->netdev_ops = &rndis_netdev_ops;
363 retval = rndis_command(dev, u.header, CONTROL_BUFFER_SIZE);
364 if (unlikely(retval < 0)) {
365 /* it might not even be an RNDIS device!! */
366 dev_err(&intf->dev, "RNDIS init failed, %d\n", retval);
367 goto fail_and_release;
369 tmp = le32_to_cpu(u.init_c->max_transfer_size);
370 if (tmp < dev->hard_mtu) {
371 if (tmp <= net->hard_header_len) {
373 "dev can't take %u byte packets (max %u)\n",
376 goto halt_fail_and_release;
379 "dev can't take %u byte packets (max %u), "
380 "adjusting MTU to %u\n",
381 dev->hard_mtu, tmp, tmp - net->hard_header_len);
383 net->mtu = dev->hard_mtu - net->hard_header_len;
386 /* REVISIT: peripheral "alignment" request is ignored ... */
388 "hard mtu %u (%u from dev), rx buflen %zu, align %d\n",
389 dev->hard_mtu, tmp, dev->rx_urb_size,
390 1 << le32_to_cpu(u.init_c->packet_alignment));
392 /* module has some device initialization code needs to be done right
393 * after RNDIS_INIT */
394 if (dev->driver_info->early_init &&
395 dev->driver_info->early_init(dev) != 0)
396 goto halt_fail_and_release;
398 /* Check physical medium */
400 reply_len = sizeof *phym;
401 retval = rndis_query(dev, intf, u.buf,
402 RNDIS_OID_GEN_PHYSICAL_MEDIUM,
403 reply_len, (void **)&phym, &reply_len);
404 if (retval != 0 || !phym) {
405 /* OID is optional so don't fail here. */
406 phym_unspec = cpu_to_le32(RNDIS_PHYSICAL_MEDIUM_UNSPECIFIED);
409 if ((flags & FLAG_RNDIS_PHYM_WIRELESS) &&
410 le32_to_cpup(phym) != RNDIS_PHYSICAL_MEDIUM_WIRELESS_LAN) {
411 netif_dbg(dev, probe, dev->net,
412 "driver requires wireless physical medium, but device is not\n");
414 goto halt_fail_and_release;
416 if ((flags & FLAG_RNDIS_PHYM_NOT_WIRELESS) &&
417 le32_to_cpup(phym) == RNDIS_PHYSICAL_MEDIUM_WIRELESS_LAN) {
418 netif_dbg(dev, probe, dev->net,
419 "driver requires non-wireless physical medium, but device is wireless.\n");
421 goto halt_fail_and_release;
424 /* Get designated host ethernet address */
425 reply_len = ETH_ALEN;
426 retval = rndis_query(dev, intf, u.buf,
427 RNDIS_OID_802_3_PERMANENT_ADDRESS,
428 48, (void **) &bp, &reply_len);
429 if (unlikely(retval< 0)) {
430 dev_err(&intf->dev, "rndis get ethaddr, %d\n", retval);
431 goto halt_fail_and_release;
435 eth_hw_addr_random(net);
437 ether_addr_copy(net->dev_addr, bp);
439 /* set a nonzero filter to enable data transfers */
440 memset(u.set, 0, sizeof *u.set);
441 u.set->msg_type = cpu_to_le32(RNDIS_MSG_SET);
442 u.set->msg_len = cpu_to_le32(4 + sizeof *u.set);
443 u.set->oid = cpu_to_le32(RNDIS_OID_GEN_CURRENT_PACKET_FILTER);
444 u.set->len = cpu_to_le32(4);
445 u.set->offset = cpu_to_le32((sizeof *u.set) - 8);
446 *(__le32 *)(u.buf + sizeof *u.set) = cpu_to_le32(RNDIS_DEFAULT_FILTER);
448 retval = rndis_command(dev, u.header, CONTROL_BUFFER_SIZE);
449 if (unlikely(retval < 0)) {
450 dev_err(&intf->dev, "rndis set packet filter, %d\n", retval);
451 goto halt_fail_and_release;
459 halt_fail_and_release:
460 memset(u.halt, 0, sizeof *u.halt);
461 u.halt->msg_type = cpu_to_le32(RNDIS_MSG_HALT);
462 u.halt->msg_len = cpu_to_le32(sizeof *u.halt);
463 (void) rndis_command(dev, (void *)u.halt, CONTROL_BUFFER_SIZE);
465 usb_set_intfdata(info->data, NULL);
466 usb_driver_release_interface(driver_of(intf), info->data);
472 EXPORT_SYMBOL_GPL(generic_rndis_bind);
474 static int rndis_bind(struct usbnet *dev, struct usb_interface *intf)
476 return generic_rndis_bind(dev, intf, FLAG_RNDIS_PHYM_NOT_WIRELESS);
479 void rndis_unbind(struct usbnet *dev, struct usb_interface *intf)
481 struct rndis_halt *halt;
483 /* try to clear any rndis state/activity (no i/o from stack!) */
484 halt = kzalloc(CONTROL_BUFFER_SIZE, GFP_KERNEL);
486 halt->msg_type = cpu_to_le32(RNDIS_MSG_HALT);
487 halt->msg_len = cpu_to_le32(sizeof *halt);
488 (void) rndis_command(dev, (void *)halt, CONTROL_BUFFER_SIZE);
492 usbnet_cdc_unbind(dev, intf);
494 EXPORT_SYMBOL_GPL(rndis_unbind);
497 * DATA -- host must not write zlps
499 int rndis_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
501 /* This check is no longer done by usbnet */
502 if (skb->len < dev->net->hard_header_len)
505 /* peripheral may have batched packets to us... */
506 while (likely(skb->len)) {
507 struct rndis_data_hdr *hdr = (void *)skb->data;
508 struct sk_buff *skb2;
509 u32 msg_type, msg_len, data_offset, data_len;
511 msg_type = le32_to_cpu(hdr->msg_type);
512 msg_len = le32_to_cpu(hdr->msg_len);
513 data_offset = le32_to_cpu(hdr->data_offset);
514 data_len = le32_to_cpu(hdr->data_len);
516 /* don't choke if we see oob, per-packet data, etc */
517 if (unlikely(msg_type != RNDIS_MSG_PACKET || skb->len < msg_len
518 || (data_offset + data_len + 8) > msg_len)) {
519 dev->net->stats.rx_frame_errors++;
520 netdev_dbg(dev->net, "bad rndis message %d/%d/%d/%d, len %d\n",
521 le32_to_cpu(hdr->msg_type),
522 msg_len, data_offset, data_len, skb->len);
525 skb_pull(skb, 8 + data_offset);
527 /* at most one packet left? */
528 if (likely((data_len - skb->len) <= sizeof *hdr)) {
529 skb_trim(skb, data_len);
533 /* try to return all the packets in the batch */
534 skb2 = skb_clone(skb, GFP_ATOMIC);
537 skb_pull(skb, msg_len - sizeof *hdr);
538 skb_trim(skb2, data_len);
539 usbnet_skb_return(dev, skb2);
542 /* caller will usbnet_skb_return the remaining packet */
545 EXPORT_SYMBOL_GPL(rndis_rx_fixup);
548 rndis_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
550 struct rndis_data_hdr *hdr;
551 struct sk_buff *skb2;
552 unsigned len = skb->len;
554 if (likely(!skb_cloned(skb))) {
555 int room = skb_headroom(skb);
557 /* enough head room as-is? */
558 if (unlikely((sizeof *hdr) <= room))
561 /* enough room, but needs to be readjusted? */
562 room += skb_tailroom(skb);
563 if (likely((sizeof *hdr) <= room)) {
564 skb->data = memmove(skb->head + sizeof *hdr,
566 skb_set_tail_pointer(skb, len);
571 /* create a new skb, with the correct size (and tailpad) */
572 skb2 = skb_copy_expand(skb, sizeof *hdr, 1, flags);
573 dev_kfree_skb_any(skb);
578 /* fill out the RNDIS header. we won't bother trying to batch
579 * packets; Linux minimizes wasted bandwidth through tx queues.
582 hdr = __skb_push(skb, sizeof *hdr);
583 memset(hdr, 0, sizeof *hdr);
584 hdr->msg_type = cpu_to_le32(RNDIS_MSG_PACKET);
585 hdr->msg_len = cpu_to_le32(skb->len);
586 hdr->data_offset = cpu_to_le32(sizeof(*hdr) - 8);
587 hdr->data_len = cpu_to_le32(len);
589 /* FIXME make the last packet always be short ... */
592 EXPORT_SYMBOL_GPL(rndis_tx_fixup);
595 static const struct driver_info rndis_info = {
596 .description = "RNDIS device",
597 .flags = FLAG_ETHER | FLAG_POINTTOPOINT | FLAG_FRAMING_RN | FLAG_NO_SETINT,
599 .unbind = rndis_unbind,
600 .status = rndis_status,
601 .rx_fixup = rndis_rx_fixup,
602 .tx_fixup = rndis_tx_fixup,
605 static const struct driver_info rndis_poll_status_info = {
606 .description = "RNDIS device (poll status before control)",
607 .flags = FLAG_ETHER | FLAG_POINTTOPOINT | FLAG_FRAMING_RN | FLAG_NO_SETINT,
608 .data = RNDIS_DRIVER_DATA_POLL_STATUS,
610 .unbind = rndis_unbind,
611 .status = rndis_status,
612 .rx_fixup = rndis_rx_fixup,
613 .tx_fixup = rndis_tx_fixup,
616 /*-------------------------------------------------------------------------*/
618 static const struct usb_device_id products [] = {
620 /* 2Wire HomePortal 1000SW */
621 USB_DEVICE_AND_INTERFACE_INFO(0x1630, 0x0042,
622 USB_CLASS_COMM, 2 /* ACM */, 0x0ff),
623 .driver_info = (unsigned long) &rndis_poll_status_info,
625 /* Hytera Communications DMR radios' "Radio to PC Network" */
626 USB_VENDOR_AND_INTERFACE_INFO(0x238b,
627 USB_CLASS_COMM, 2 /* ACM */, 0x0ff),
628 .driver_info = (unsigned long)&rndis_info,
630 /* RNDIS is MSFT's un-official variant of CDC ACM */
631 USB_INTERFACE_INFO(USB_CLASS_COMM, 2 /* ACM */, 0x0ff),
632 .driver_info = (unsigned long) &rndis_info,
634 /* "ActiveSync" is an undocumented variant of RNDIS, used in WM5 */
635 USB_INTERFACE_INFO(USB_CLASS_MISC, 1, 1),
636 .driver_info = (unsigned long) &rndis_poll_status_info,
638 /* RNDIS for tethering */
639 USB_INTERFACE_INFO(USB_CLASS_WIRELESS_CONTROLLER, 1, 3),
640 .driver_info = (unsigned long) &rndis_info,
642 /* Novatel Verizon USB730L */
643 USB_INTERFACE_INFO(USB_CLASS_MISC, 4, 1),
644 .driver_info = (unsigned long) &rndis_info,
648 MODULE_DEVICE_TABLE(usb, products);
650 static struct usb_driver rndis_driver = {
651 .name = "rndis_host",
652 .id_table = products,
653 .probe = usbnet_probe,
654 .disconnect = usbnet_disconnect,
655 .suspend = usbnet_suspend,
656 .resume = usbnet_resume,
657 .disable_hub_initiated_lpm = 1,
660 module_usb_driver(rndis_driver);
662 MODULE_AUTHOR("David Brownell");
663 MODULE_DESCRIPTION("USB Host side RNDIS driver");
664 MODULE_LICENSE("GPL");