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1/*
2 * Copyright (c) 2012 Smith Micro Software, Inc.
3 * Copyright (c) 2012 Bjørn Mork <bjorn@mork.no>
4 *
5 * This driver is based on and reuse most of cdc_ncm, which is
6 * Copyright (C) ST-Ericsson 2010-2012
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * version 2 as published by the Free Software Foundation.
11 */
12
13#include <linux/module.h>
14#include <linux/netdevice.h>
15#include <linux/ethtool.h>
16#include <linux/if_vlan.h>
17#include <linux/ip.h>
18#include <linux/mii.h>
19#include <linux/usb.h>
20#include <linux/usb/cdc.h>
21#include <linux/usb/usbnet.h>
22#include <linux/usb/cdc-wdm.h>
23#include <linux/usb/cdc_ncm.h>
24#include <net/ipv6.h>
25#include <net/addrconf.h>
26
27/* driver specific data - must match cdc_ncm usage */
28struct cdc_mbim_state {
29 struct cdc_ncm_ctx *ctx;
30 atomic_t pmcount;
31 struct usb_driver *subdriver;
32 struct usb_interface *control;
33 struct usb_interface *data;
34};
35
36/* using a counter to merge subdriver requests with our own into a combined state */
37static int cdc_mbim_manage_power(struct usbnet *dev, int on)
38{
39 struct cdc_mbim_state *info = (void *)&dev->data;
40 int rv = 0;
41
42 dev_dbg(&dev->intf->dev, "%s() pmcount=%d, on=%d\n", __func__, atomic_read(&info->pmcount), on);
43
44 if ((on && atomic_add_return(1, &info->pmcount) == 1) || (!on && atomic_dec_and_test(&info->pmcount))) {
45 /* need autopm_get/put here to ensure the usbcore sees the new value */
46 rv = usb_autopm_get_interface(dev->intf);
47 dev->intf->needs_remote_wakeup = on;
48 if (!rv)
49 usb_autopm_put_interface(dev->intf);
50 }
51 return 0;
52}
53
54static int cdc_mbim_wdm_manage_power(struct usb_interface *intf, int status)
55{
56 struct usbnet *dev = usb_get_intfdata(intf);
57
58 /* can be called while disconnecting */
59 if (!dev)
60 return 0;
61
62 return cdc_mbim_manage_power(dev, status);
63}
64
65
66static int cdc_mbim_bind(struct usbnet *dev, struct usb_interface *intf)
67{
68 struct cdc_ncm_ctx *ctx;
69 struct usb_driver *subdriver = ERR_PTR(-ENODEV);
70 int ret = -ENODEV;
71 u8 data_altsetting = cdc_ncm_select_altsetting(dev, intf);
72 struct cdc_mbim_state *info = (void *)&dev->data;
73
74 /* Probably NCM, defer for cdc_ncm_bind */
75 if (!cdc_ncm_comm_intf_is_mbim(intf->cur_altsetting))
76 goto err;
77
78 ret = cdc_ncm_bind_common(dev, intf, data_altsetting);
79 if (ret)
80 goto err;
81
82 ctx = info->ctx;
83
84 /* The MBIM descriptor and the status endpoint are required */
85 if (ctx->mbim_desc && dev->status)
86 subdriver = usb_cdc_wdm_register(ctx->control,
87 &dev->status->desc,
88 le16_to_cpu(ctx->mbim_desc->wMaxControlMessage),
89 cdc_mbim_wdm_manage_power);
90 if (IS_ERR(subdriver)) {
91 ret = PTR_ERR(subdriver);
92 cdc_ncm_unbind(dev, intf);
93 goto err;
94 }
95
96 /* can't let usbnet use the interrupt endpoint */
97 dev->status = NULL;
98 info->subdriver = subdriver;
99
100 /* MBIM cannot do ARP */
101 dev->net->flags |= IFF_NOARP;
102
103 /* no need to put the VLAN tci in the packet headers */
104 dev->net->features |= NETIF_F_HW_VLAN_CTAG_TX;
105err:
106 return ret;
107}
108
109static void cdc_mbim_unbind(struct usbnet *dev, struct usb_interface *intf)
110{
111 struct cdc_mbim_state *info = (void *)&dev->data;
112 struct cdc_ncm_ctx *ctx = info->ctx;
113
114 /* disconnect subdriver from control interface */
115 if (info->subdriver && info->subdriver->disconnect)
116 info->subdriver->disconnect(ctx->control);
117 info->subdriver = NULL;
118
119 /* let NCM unbind clean up both control and data interface */
120 cdc_ncm_unbind(dev, intf);
121}
122
123/* verify that the ethernet protocol is IPv4 or IPv6 */
124static bool is_ip_proto(__be16 proto)
125{
126 switch (proto) {
127 case htons(ETH_P_IP):
128 case htons(ETH_P_IPV6):
129 return true;
130 }
131 return false;
132}
133
134static struct sk_buff *cdc_mbim_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
135{
136 struct sk_buff *skb_out;
137 struct cdc_mbim_state *info = (void *)&dev->data;
138 struct cdc_ncm_ctx *ctx = info->ctx;
139 __le32 sign = cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN);
140 u16 tci = 0;
141 bool is_ip;
142 u8 *c;
143
144 if (!ctx)
145 goto error;
146
147 if (skb) {
148 if (skb->len <= ETH_HLEN)
149 goto error;
150
151 /* Some applications using e.g. packet sockets will
152 * bypass the VLAN acceleration and create tagged
153 * ethernet frames directly. We primarily look for
154 * the accelerated out-of-band tag, but fall back if
155 * required
156 */
157 skb_reset_mac_header(skb);
158 if (vlan_get_tag(skb, &tci) < 0 && skb->len > VLAN_ETH_HLEN &&
159 __vlan_get_tag(skb, &tci) == 0) {
160 is_ip = is_ip_proto(vlan_eth_hdr(skb)->h_vlan_encapsulated_proto);
161 skb_pull(skb, VLAN_ETH_HLEN);
162 } else {
163 is_ip = is_ip_proto(eth_hdr(skb)->h_proto);
164 skb_pull(skb, ETH_HLEN);
165 }
166
167 /* mapping VLANs to MBIM sessions:
168 * no tag => IPS session <0>
169 * 1 - 255 => IPS session <vlanid>
170 * 256 - 511 => DSS session <vlanid - 256>
171 * 512 - 4095 => unsupported, drop
172 */
173 switch (tci & 0x0f00) {
174 case 0x0000: /* VLAN ID 0 - 255 */
175 if (!is_ip)
176 goto error;
177 c = (u8 *)&sign;
178 c[3] = tci;
179 break;
180 case 0x0100: /* VLAN ID 256 - 511 */
181 sign = cpu_to_le32(USB_CDC_MBIM_NDP16_DSS_SIGN);
182 c = (u8 *)&sign;
183 c[3] = tci;
184 break;
185 default:
186 netif_err(dev, tx_err, dev->net,
187 "unsupported tci=0x%04x\n", tci);
188 goto error;
189 }
190 }
191
192 spin_lock_bh(&ctx->mtx);
193 skb_out = cdc_ncm_fill_tx_frame(dev, skb, sign);
194 spin_unlock_bh(&ctx->mtx);
195 return skb_out;
196
197error:
198 if (skb)
199 dev_kfree_skb_any(skb);
200
201 return NULL;
202}
203
204/* Some devices are known to send Neigbor Solicitation messages and
205 * require Neigbor Advertisement replies. The IPv6 core will not
206 * respond since IFF_NOARP is set, so we must handle them ourselves.
207 */
208static void do_neigh_solicit(struct usbnet *dev, u8 *buf, u16 tci)
209{
210 struct ipv6hdr *iph = (void *)buf;
211 struct nd_msg *msg = (void *)(iph + 1);
212 struct net_device *netdev;
213 struct inet6_dev *in6_dev;
214 bool is_router;
215
216 /* we'll only respond to requests from unicast addresses to
217 * our solicited node addresses.
218 */
219 if (!ipv6_addr_is_solict_mult(&iph->daddr) ||
220 !(ipv6_addr_type(&iph->saddr) & IPV6_ADDR_UNICAST))
221 return;
222
223 /* need to send the NA on the VLAN dev, if any */
224 rcu_read_lock();
225 if (tci) {
226 netdev = __vlan_find_dev_deep(dev->net, htons(ETH_P_8021Q),
227 tci);
228 if (!netdev) {
229 rcu_read_unlock();
230 return;
231 }
232 } else {
233 netdev = dev->net;
234 }
235 dev_hold(netdev);
236 rcu_read_unlock();
237
238 in6_dev = in6_dev_get(netdev);
239 if (!in6_dev)
240 goto out;
241 is_router = !!in6_dev->cnf.forwarding;
242 in6_dev_put(in6_dev);
243
244 /* ipv6_stub != NULL if in6_dev_get returned an inet6_dev */
245 ipv6_stub->ndisc_send_na(netdev, NULL, &iph->saddr, &msg->target,
246 is_router /* router */,
247 true /* solicited */,
248 false /* override */,
249 true /* inc_opt */);
250out:
251 dev_put(netdev);
252}
253
254static bool is_neigh_solicit(u8 *buf, size_t len)
255{
256 struct ipv6hdr *iph = (void *)buf;
257 struct nd_msg *msg = (void *)(iph + 1);
258
259 return (len >= sizeof(struct ipv6hdr) + sizeof(struct nd_msg) &&
260 iph->nexthdr == IPPROTO_ICMPV6 &&
261 msg->icmph.icmp6_code == 0 &&
262 msg->icmph.icmp6_type == NDISC_NEIGHBOUR_SOLICITATION);
263}
264
265
266static struct sk_buff *cdc_mbim_process_dgram(struct usbnet *dev, u8 *buf, size_t len, u16 tci)
267{
268 __be16 proto = htons(ETH_P_802_3);
269 struct sk_buff *skb = NULL;
270
271 if (tci < 256) { /* IPS session? */
272 if (len < sizeof(struct iphdr))
273 goto err;
274
275 switch (*buf & 0xf0) {
276 case 0x40:
277 proto = htons(ETH_P_IP);
278 break;
279 case 0x60:
280 if (is_neigh_solicit(buf, len))
281 do_neigh_solicit(dev, buf, tci);
282 proto = htons(ETH_P_IPV6);
283 break;
284 default:
285 goto err;
286 }
287 }
288
289 skb = netdev_alloc_skb_ip_align(dev->net, len + ETH_HLEN);
290 if (!skb)
291 goto err;
292
293 /* add an ethernet header */
294 skb_put(skb, ETH_HLEN);
295 skb_reset_mac_header(skb);
296 eth_hdr(skb)->h_proto = proto;
297 memset(eth_hdr(skb)->h_source, 0, ETH_ALEN);
298 memcpy(eth_hdr(skb)->h_dest, dev->net->dev_addr, ETH_ALEN);
299
300 /* add datagram */
301 memcpy(skb_put(skb, len), buf, len);
302
303 /* map MBIM session to VLAN */
304 if (tci)
305 vlan_put_tag(skb, htons(ETH_P_8021Q), tci);
306err:
307 return skb;
308}
309
310static int cdc_mbim_rx_fixup(struct usbnet *dev, struct sk_buff *skb_in)
311{
312 struct sk_buff *skb;
313 struct cdc_mbim_state *info = (void *)&dev->data;
314 struct cdc_ncm_ctx *ctx = info->ctx;
315 int len;
316 int nframes;
317 int x;
318 int offset;
319 struct usb_cdc_ncm_ndp16 *ndp16;
320 struct usb_cdc_ncm_dpe16 *dpe16;
321 int ndpoffset;
322 int loopcount = 50; /* arbitrary max preventing infinite loop */
323 u8 *c;
324 u16 tci;
325
326 ndpoffset = cdc_ncm_rx_verify_nth16(ctx, skb_in);
327 if (ndpoffset < 0)
328 goto error;
329
330next_ndp:
331 nframes = cdc_ncm_rx_verify_ndp16(skb_in, ndpoffset);
332 if (nframes < 0)
333 goto error;
334
335 ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb_in->data + ndpoffset);
336
337 switch (ndp16->dwSignature & cpu_to_le32(0x00ffffff)) {
338 case cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN):
339 c = (u8 *)&ndp16->dwSignature;
340 tci = c[3];
341 break;
342 case cpu_to_le32(USB_CDC_MBIM_NDP16_DSS_SIGN):
343 c = (u8 *)&ndp16->dwSignature;
344 tci = c[3] + 256;
345 break;
346 default:
347 netif_dbg(dev, rx_err, dev->net,
348 "unsupported NDP signature <0x%08x>\n",
349 le32_to_cpu(ndp16->dwSignature));
350 goto err_ndp;
351
352 }
353
354 dpe16 = ndp16->dpe16;
355 for (x = 0; x < nframes; x++, dpe16++) {
356 offset = le16_to_cpu(dpe16->wDatagramIndex);
357 len = le16_to_cpu(dpe16->wDatagramLength);
358
359 /*
360 * CDC NCM ch. 3.7
361 * All entries after first NULL entry are to be ignored
362 */
363 if ((offset == 0) || (len == 0)) {
364 if (!x)
365 goto err_ndp; /* empty NTB */
366 break;
367 }
368
369 /* sanity checking */
370 if (((offset + len) > skb_in->len) || (len > ctx->rx_max)) {
371 netif_dbg(dev, rx_err, dev->net,
372 "invalid frame detected (ignored) offset[%u]=%u, length=%u, skb=%p\n",
373 x, offset, len, skb_in);
374 if (!x)
375 goto err_ndp;
376 break;
377 } else {
378 skb = cdc_mbim_process_dgram(dev, skb_in->data + offset, len, tci);
379 if (!skb)
380 goto error;
381 usbnet_skb_return(dev, skb);
382 }
383 }
384err_ndp:
385 /* are there more NDPs to process? */
386 ndpoffset = le16_to_cpu(ndp16->wNextNdpIndex);
387 if (ndpoffset && loopcount--)
388 goto next_ndp;
389
390 return 1;
391error:
392 return 0;
393}
394
395static int cdc_mbim_suspend(struct usb_interface *intf, pm_message_t message)
396{
397 int ret = -ENODEV;
398 struct usbnet *dev = usb_get_intfdata(intf);
399 struct cdc_mbim_state *info = (void *)&dev->data;
400 struct cdc_ncm_ctx *ctx = info->ctx;
401
402 if (!ctx)
403 goto error;
404
405 /*
406 * Both usbnet_suspend() and subdriver->suspend() MUST return 0
407 * in system sleep context, otherwise, the resume callback has
408 * to recover device from previous suspend failure.
409 */
410 ret = usbnet_suspend(intf, message);
411 if (ret < 0)
412 goto error;
413
414 if (intf == ctx->control && info->subdriver && info->subdriver->suspend)
415 ret = info->subdriver->suspend(intf, message);
416 if (ret < 0)
417 usbnet_resume(intf);
418
419error:
420 return ret;
421}
422
423static int cdc_mbim_resume(struct usb_interface *intf)
424{
425 int ret = 0;
426 struct usbnet *dev = usb_get_intfdata(intf);
427 struct cdc_mbim_state *info = (void *)&dev->data;
428 struct cdc_ncm_ctx *ctx = info->ctx;
429 bool callsub = (intf == ctx->control && info->subdriver && info->subdriver->resume);
430
431 if (callsub)
432 ret = info->subdriver->resume(intf);
433 if (ret < 0)
434 goto err;
435 ret = usbnet_resume(intf);
436 if (ret < 0 && callsub)
437 info->subdriver->suspend(intf, PMSG_SUSPEND);
438err:
439 return ret;
440}
441
442static const struct driver_info cdc_mbim_info = {
443 .description = "CDC MBIM",
444 .flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN,
445 .bind = cdc_mbim_bind,
446 .unbind = cdc_mbim_unbind,
447 .manage_power = cdc_mbim_manage_power,
448 .rx_fixup = cdc_mbim_rx_fixup,
449 .tx_fixup = cdc_mbim_tx_fixup,
450};
451
452/* MBIM and NCM devices should not need a ZLP after NTBs with
453 * dwNtbOutMaxSize length. Nevertheless, a number of devices from
454 * different vendor IDs will fail unless we send ZLPs, forcing us
455 * to make this the default.
456 *
457 * This default may cause a performance penalty for spec conforming
458 * devices wanting to take advantage of optimizations possible without
459 * ZLPs. A whitelist is added in an attempt to avoid this for devices
460 * known to conform to the MBIM specification.
461 *
462 * All known devices supporting NCM compatibility mode are also
463 * conforming to the NCM and MBIM specifications. For this reason, the
464 * NCM subclass entry is also in the ZLP whitelist.
465 */
466static const struct driver_info cdc_mbim_info_zlp = {
467 .description = "CDC MBIM",
468 .flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN | FLAG_SEND_ZLP,
469 .bind = cdc_mbim_bind,
470 .unbind = cdc_mbim_unbind,
471 .manage_power = cdc_mbim_manage_power,
472 .rx_fixup = cdc_mbim_rx_fixup,
473 .tx_fixup = cdc_mbim_tx_fixup,
474};
475
476static const struct usb_device_id mbim_devs[] = {
477 /* This duplicate NCM entry is intentional. MBIM devices can
478 * be disguised as NCM by default, and this is necessary to
479 * allow us to bind the correct driver_info to such devices.
480 *
481 * bind() will sort out this for us, selecting the correct
482 * entry and reject the other
483 */
484 { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
485 .driver_info = (unsigned long)&cdc_mbim_info,
486 },
487 /* ZLP conformance whitelist: All Ericsson MBIM devices */
488 { USB_VENDOR_AND_INTERFACE_INFO(0x0bdb, USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
489 .driver_info = (unsigned long)&cdc_mbim_info,
490 },
491 /* default entry */
492 { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
493 .driver_info = (unsigned long)&cdc_mbim_info_zlp,
494 },
495 {
496 },
497};
498MODULE_DEVICE_TABLE(usb, mbim_devs);
499
500static struct usb_driver cdc_mbim_driver = {
501 .name = "cdc_mbim",
502 .id_table = mbim_devs,
503 .probe = usbnet_probe,
504 .disconnect = usbnet_disconnect,
505 .suspend = cdc_mbim_suspend,
506 .resume = cdc_mbim_resume,
507 .reset_resume = cdc_mbim_resume,
508 .supports_autosuspend = 1,
509 .disable_hub_initiated_lpm = 1,
510};
511module_usb_driver(cdc_mbim_driver);
512
513MODULE_AUTHOR("Greg Suarez <gsuarez@smithmicro.com>");
514MODULE_AUTHOR("Bjørn Mork <bjorn@mork.no>");
515MODULE_DESCRIPTION("USB CDC MBIM host driver");
516MODULE_LICENSE("GPL");
1/*
2 * Copyright (c) 2012 Smith Micro Software, Inc.
3 * Copyright (c) 2012 Bjørn Mork <bjorn@mork.no>
4 *
5 * This driver is based on and reuse most of cdc_ncm, which is
6 * Copyright (C) ST-Ericsson 2010-2012
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * version 2 as published by the Free Software Foundation.
11 */
12
13#include <linux/module.h>
14#include <linux/netdevice.h>
15#include <linux/ethtool.h>
16#include <linux/if_vlan.h>
17#include <linux/ip.h>
18#include <linux/mii.h>
19#include <linux/usb.h>
20#include <linux/usb/cdc.h>
21#include <linux/usb/usbnet.h>
22#include <linux/usb/cdc-wdm.h>
23#include <linux/usb/cdc_ncm.h>
24#include <net/ipv6.h>
25#include <net/addrconf.h>
26
27/* alternative VLAN for IP session 0 if not untagged */
28#define MBIM_IPS0_VID 4094
29
30/* driver specific data - must match cdc_ncm usage */
31struct cdc_mbim_state {
32 struct cdc_ncm_ctx *ctx;
33 atomic_t pmcount;
34 struct usb_driver *subdriver;
35 unsigned long _unused;
36 unsigned long flags;
37};
38
39/* flags for the cdc_mbim_state.flags field */
40enum cdc_mbim_flags {
41 FLAG_IPS0_VLAN = 1 << 0, /* IP session 0 is tagged */
42};
43
44/* using a counter to merge subdriver requests with our own into a combined state */
45static int cdc_mbim_manage_power(struct usbnet *dev, int on)
46{
47 struct cdc_mbim_state *info = (void *)&dev->data;
48 int rv = 0;
49
50 dev_dbg(&dev->intf->dev, "%s() pmcount=%d, on=%d\n", __func__, atomic_read(&info->pmcount), on);
51
52 if ((on && atomic_add_return(1, &info->pmcount) == 1) || (!on && atomic_dec_and_test(&info->pmcount))) {
53 /* need autopm_get/put here to ensure the usbcore sees the new value */
54 rv = usb_autopm_get_interface(dev->intf);
55 dev->intf->needs_remote_wakeup = on;
56 if (!rv)
57 usb_autopm_put_interface(dev->intf);
58 }
59 return 0;
60}
61
62static int cdc_mbim_wdm_manage_power(struct usb_interface *intf, int status)
63{
64 struct usbnet *dev = usb_get_intfdata(intf);
65
66 /* can be called while disconnecting */
67 if (!dev)
68 return 0;
69
70 return cdc_mbim_manage_power(dev, status);
71}
72
73static int cdc_mbim_rx_add_vid(struct net_device *netdev, __be16 proto, u16 vid)
74{
75 struct usbnet *dev = netdev_priv(netdev);
76 struct cdc_mbim_state *info = (void *)&dev->data;
77
78 /* creation of this VLAN is a request to tag IP session 0 */
79 if (vid == MBIM_IPS0_VID)
80 info->flags |= FLAG_IPS0_VLAN;
81 else
82 if (vid >= 512) /* we don't map these to MBIM session */
83 return -EINVAL;
84 return 0;
85}
86
87static int cdc_mbim_rx_kill_vid(struct net_device *netdev, __be16 proto, u16 vid)
88{
89 struct usbnet *dev = netdev_priv(netdev);
90 struct cdc_mbim_state *info = (void *)&dev->data;
91
92 /* this is a request for an untagged IP session 0 */
93 if (vid == MBIM_IPS0_VID)
94 info->flags &= ~FLAG_IPS0_VLAN;
95 return 0;
96}
97
98static const struct net_device_ops cdc_mbim_netdev_ops = {
99 .ndo_open = usbnet_open,
100 .ndo_stop = usbnet_stop,
101 .ndo_start_xmit = usbnet_start_xmit,
102 .ndo_tx_timeout = usbnet_tx_timeout,
103 .ndo_change_mtu = cdc_ncm_change_mtu,
104 .ndo_set_mac_address = eth_mac_addr,
105 .ndo_validate_addr = eth_validate_addr,
106 .ndo_vlan_rx_add_vid = cdc_mbim_rx_add_vid,
107 .ndo_vlan_rx_kill_vid = cdc_mbim_rx_kill_vid,
108};
109
110/* Change the control interface altsetting and update the .driver_info
111 * pointer if the matching entry after changing class codes points to
112 * a different struct
113 */
114static int cdc_mbim_set_ctrlalt(struct usbnet *dev, struct usb_interface *intf, u8 alt)
115{
116 struct usb_driver *driver = to_usb_driver(intf->dev.driver);
117 const struct usb_device_id *id;
118 struct driver_info *info;
119 int ret;
120
121 ret = usb_set_interface(dev->udev,
122 intf->cur_altsetting->desc.bInterfaceNumber,
123 alt);
124 if (ret)
125 return ret;
126
127 id = usb_match_id(intf, driver->id_table);
128 if (!id)
129 return -ENODEV;
130
131 info = (struct driver_info *)id->driver_info;
132 if (info != dev->driver_info) {
133 dev_dbg(&intf->dev, "driver_info updated to '%s'\n",
134 info->description);
135 dev->driver_info = info;
136 }
137 return 0;
138}
139
140static int cdc_mbim_bind(struct usbnet *dev, struct usb_interface *intf)
141{
142 struct cdc_ncm_ctx *ctx;
143 struct usb_driver *subdriver = ERR_PTR(-ENODEV);
144 int ret = -ENODEV;
145 u8 data_altsetting = 1;
146 struct cdc_mbim_state *info = (void *)&dev->data;
147
148 /* should we change control altsetting on a NCM/MBIM function? */
149 if (cdc_ncm_select_altsetting(intf) == CDC_NCM_COMM_ALTSETTING_MBIM) {
150 data_altsetting = CDC_NCM_DATA_ALTSETTING_MBIM;
151 ret = cdc_mbim_set_ctrlalt(dev, intf, CDC_NCM_COMM_ALTSETTING_MBIM);
152 if (ret)
153 goto err;
154 ret = -ENODEV;
155 }
156
157 /* we will hit this for NCM/MBIM functions if prefer_mbim is false */
158 if (!cdc_ncm_comm_intf_is_mbim(intf->cur_altsetting))
159 goto err;
160
161 ret = cdc_ncm_bind_common(dev, intf, data_altsetting, dev->driver_info->data);
162 if (ret)
163 goto err;
164
165 ctx = info->ctx;
166
167 /* The MBIM descriptor and the status endpoint are required */
168 if (ctx->mbim_desc && dev->status)
169 subdriver = usb_cdc_wdm_register(ctx->control,
170 &dev->status->desc,
171 le16_to_cpu(ctx->mbim_desc->wMaxControlMessage),
172 cdc_mbim_wdm_manage_power);
173 if (IS_ERR(subdriver)) {
174 ret = PTR_ERR(subdriver);
175 cdc_ncm_unbind(dev, intf);
176 goto err;
177 }
178
179 /* can't let usbnet use the interrupt endpoint */
180 dev->status = NULL;
181 info->subdriver = subdriver;
182
183 /* MBIM cannot do ARP */
184 dev->net->flags |= IFF_NOARP;
185
186 /* no need to put the VLAN tci in the packet headers */
187 dev->net->features |= NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_FILTER;
188
189 /* monitor VLAN additions and removals */
190 dev->net->netdev_ops = &cdc_mbim_netdev_ops;
191err:
192 return ret;
193}
194
195static void cdc_mbim_unbind(struct usbnet *dev, struct usb_interface *intf)
196{
197 struct cdc_mbim_state *info = (void *)&dev->data;
198 struct cdc_ncm_ctx *ctx = info->ctx;
199
200 /* disconnect subdriver from control interface */
201 if (info->subdriver && info->subdriver->disconnect)
202 info->subdriver->disconnect(ctx->control);
203 info->subdriver = NULL;
204
205 /* let NCM unbind clean up both control and data interface */
206 cdc_ncm_unbind(dev, intf);
207}
208
209/* verify that the ethernet protocol is IPv4 or IPv6 */
210static bool is_ip_proto(__be16 proto)
211{
212 switch (proto) {
213 case htons(ETH_P_IP):
214 case htons(ETH_P_IPV6):
215 return true;
216 }
217 return false;
218}
219
220static struct sk_buff *cdc_mbim_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
221{
222 struct sk_buff *skb_out;
223 struct cdc_mbim_state *info = (void *)&dev->data;
224 struct cdc_ncm_ctx *ctx = info->ctx;
225 __le32 sign = cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN);
226 u16 tci = 0;
227 bool is_ip;
228 u8 *c;
229
230 if (!ctx)
231 goto error;
232
233 if (skb) {
234 if (skb->len <= ETH_HLEN)
235 goto error;
236
237 /* Some applications using e.g. packet sockets will
238 * bypass the VLAN acceleration and create tagged
239 * ethernet frames directly. We primarily look for
240 * the accelerated out-of-band tag, but fall back if
241 * required
242 */
243 skb_reset_mac_header(skb);
244 if (vlan_get_tag(skb, &tci) < 0 && skb->len > VLAN_ETH_HLEN &&
245 __vlan_get_tag(skb, &tci) == 0) {
246 is_ip = is_ip_proto(vlan_eth_hdr(skb)->h_vlan_encapsulated_proto);
247 skb_pull(skb, VLAN_ETH_HLEN);
248 } else {
249 is_ip = is_ip_proto(eth_hdr(skb)->h_proto);
250 skb_pull(skb, ETH_HLEN);
251 }
252
253 /* Is IP session <0> tagged too? */
254 if (info->flags & FLAG_IPS0_VLAN) {
255 /* drop all untagged packets */
256 if (!tci)
257 goto error;
258 /* map MBIM_IPS0_VID to IPS<0> */
259 if (tci == MBIM_IPS0_VID)
260 tci = 0;
261 }
262
263 /* mapping VLANs to MBIM sessions:
264 * no tag => IPS session <0> if !FLAG_IPS0_VLAN
265 * 1 - 255 => IPS session <vlanid>
266 * 256 - 511 => DSS session <vlanid - 256>
267 * 512 - 4093 => unsupported, drop
268 * 4094 => IPS session <0> if FLAG_IPS0_VLAN
269 */
270
271 switch (tci & 0x0f00) {
272 case 0x0000: /* VLAN ID 0 - 255 */
273 if (!is_ip)
274 goto error;
275 c = (u8 *)&sign;
276 c[3] = tci;
277 break;
278 case 0x0100: /* VLAN ID 256 - 511 */
279 if (is_ip)
280 goto error;
281 sign = cpu_to_le32(USB_CDC_MBIM_NDP16_DSS_SIGN);
282 c = (u8 *)&sign;
283 c[3] = tci;
284 break;
285 default:
286 netif_err(dev, tx_err, dev->net,
287 "unsupported tci=0x%04x\n", tci);
288 goto error;
289 }
290 }
291
292 spin_lock_bh(&ctx->mtx);
293 skb_out = cdc_ncm_fill_tx_frame(dev, skb, sign);
294 spin_unlock_bh(&ctx->mtx);
295 return skb_out;
296
297error:
298 if (skb)
299 dev_kfree_skb_any(skb);
300
301 return NULL;
302}
303
304/* Some devices are known to send Neigbor Solicitation messages and
305 * require Neigbor Advertisement replies. The IPv6 core will not
306 * respond since IFF_NOARP is set, so we must handle them ourselves.
307 */
308static void do_neigh_solicit(struct usbnet *dev, u8 *buf, u16 tci)
309{
310 struct ipv6hdr *iph = (void *)buf;
311 struct nd_msg *msg = (void *)(iph + 1);
312 struct net_device *netdev;
313 struct inet6_dev *in6_dev;
314 bool is_router;
315
316 /* we'll only respond to requests from unicast addresses to
317 * our solicited node addresses.
318 */
319 if (!ipv6_addr_is_solict_mult(&iph->daddr) ||
320 !(ipv6_addr_type(&iph->saddr) & IPV6_ADDR_UNICAST))
321 return;
322
323 /* need to send the NA on the VLAN dev, if any */
324 rcu_read_lock();
325 if (tci) {
326 netdev = __vlan_find_dev_deep_rcu(dev->net, htons(ETH_P_8021Q),
327 tci);
328 if (!netdev) {
329 rcu_read_unlock();
330 return;
331 }
332 } else {
333 netdev = dev->net;
334 }
335 dev_hold(netdev);
336 rcu_read_unlock();
337
338 in6_dev = in6_dev_get(netdev);
339 if (!in6_dev)
340 goto out;
341 is_router = !!in6_dev->cnf.forwarding;
342 in6_dev_put(in6_dev);
343
344 /* ipv6_stub != NULL if in6_dev_get returned an inet6_dev */
345 ipv6_stub->ndisc_send_na(netdev, &iph->saddr, &msg->target,
346 is_router /* router */,
347 true /* solicited */,
348 false /* override */,
349 true /* inc_opt */);
350out:
351 dev_put(netdev);
352}
353
354static bool is_neigh_solicit(u8 *buf, size_t len)
355{
356 struct ipv6hdr *iph = (void *)buf;
357 struct nd_msg *msg = (void *)(iph + 1);
358
359 return (len >= sizeof(struct ipv6hdr) + sizeof(struct nd_msg) &&
360 iph->nexthdr == IPPROTO_ICMPV6 &&
361 msg->icmph.icmp6_code == 0 &&
362 msg->icmph.icmp6_type == NDISC_NEIGHBOUR_SOLICITATION);
363}
364
365
366static struct sk_buff *cdc_mbim_process_dgram(struct usbnet *dev, u8 *buf, size_t len, u16 tci)
367{
368 __be16 proto = htons(ETH_P_802_3);
369 struct sk_buff *skb = NULL;
370
371 if (tci < 256 || tci == MBIM_IPS0_VID) { /* IPS session? */
372 if (len < sizeof(struct iphdr))
373 goto err;
374
375 switch (*buf & 0xf0) {
376 case 0x40:
377 proto = htons(ETH_P_IP);
378 break;
379 case 0x60:
380 if (is_neigh_solicit(buf, len))
381 do_neigh_solicit(dev, buf, tci);
382 proto = htons(ETH_P_IPV6);
383 break;
384 default:
385 goto err;
386 }
387 }
388
389 skb = netdev_alloc_skb_ip_align(dev->net, len + ETH_HLEN);
390 if (!skb)
391 goto err;
392
393 /* add an ethernet header */
394 skb_put(skb, ETH_HLEN);
395 skb_reset_mac_header(skb);
396 eth_hdr(skb)->h_proto = proto;
397 eth_zero_addr(eth_hdr(skb)->h_source);
398 memcpy(eth_hdr(skb)->h_dest, dev->net->dev_addr, ETH_ALEN);
399
400 /* add datagram */
401 memcpy(skb_put(skb, len), buf, len);
402
403 /* map MBIM session to VLAN */
404 if (tci)
405 __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), tci);
406err:
407 return skb;
408}
409
410static int cdc_mbim_rx_fixup(struct usbnet *dev, struct sk_buff *skb_in)
411{
412 struct sk_buff *skb;
413 struct cdc_mbim_state *info = (void *)&dev->data;
414 struct cdc_ncm_ctx *ctx = info->ctx;
415 int len;
416 int nframes;
417 int x;
418 int offset;
419 struct usb_cdc_ncm_ndp16 *ndp16;
420 struct usb_cdc_ncm_dpe16 *dpe16;
421 int ndpoffset;
422 int loopcount = 50; /* arbitrary max preventing infinite loop */
423 u32 payload = 0;
424 u8 *c;
425 u16 tci;
426
427 ndpoffset = cdc_ncm_rx_verify_nth16(ctx, skb_in);
428 if (ndpoffset < 0)
429 goto error;
430
431next_ndp:
432 nframes = cdc_ncm_rx_verify_ndp16(skb_in, ndpoffset);
433 if (nframes < 0)
434 goto error;
435
436 ndp16 = (struct usb_cdc_ncm_ndp16 *)(skb_in->data + ndpoffset);
437
438 switch (ndp16->dwSignature & cpu_to_le32(0x00ffffff)) {
439 case cpu_to_le32(USB_CDC_MBIM_NDP16_IPS_SIGN):
440 c = (u8 *)&ndp16->dwSignature;
441 tci = c[3];
442 /* tag IPS<0> packets too if MBIM_IPS0_VID exists */
443 if (!tci && info->flags & FLAG_IPS0_VLAN)
444 tci = MBIM_IPS0_VID;
445 break;
446 case cpu_to_le32(USB_CDC_MBIM_NDP16_DSS_SIGN):
447 c = (u8 *)&ndp16->dwSignature;
448 tci = c[3] + 256;
449 break;
450 default:
451 netif_dbg(dev, rx_err, dev->net,
452 "unsupported NDP signature <0x%08x>\n",
453 le32_to_cpu(ndp16->dwSignature));
454 goto err_ndp;
455
456 }
457
458 dpe16 = ndp16->dpe16;
459 for (x = 0; x < nframes; x++, dpe16++) {
460 offset = le16_to_cpu(dpe16->wDatagramIndex);
461 len = le16_to_cpu(dpe16->wDatagramLength);
462
463 /*
464 * CDC NCM ch. 3.7
465 * All entries after first NULL entry are to be ignored
466 */
467 if ((offset == 0) || (len == 0)) {
468 if (!x)
469 goto err_ndp; /* empty NTB */
470 break;
471 }
472
473 /* sanity checking */
474 if (((offset + len) > skb_in->len) || (len > ctx->rx_max)) {
475 netif_dbg(dev, rx_err, dev->net,
476 "invalid frame detected (ignored) offset[%u]=%u, length=%u, skb=%p\n",
477 x, offset, len, skb_in);
478 if (!x)
479 goto err_ndp;
480 break;
481 } else {
482 skb = cdc_mbim_process_dgram(dev, skb_in->data + offset, len, tci);
483 if (!skb)
484 goto error;
485 usbnet_skb_return(dev, skb);
486 payload += len; /* count payload bytes in this NTB */
487 }
488 }
489err_ndp:
490 /* are there more NDPs to process? */
491 ndpoffset = le16_to_cpu(ndp16->wNextNdpIndex);
492 if (ndpoffset && loopcount--)
493 goto next_ndp;
494
495 /* update stats */
496 ctx->rx_overhead += skb_in->len - payload;
497 ctx->rx_ntbs++;
498
499 return 1;
500error:
501 return 0;
502}
503
504static int cdc_mbim_suspend(struct usb_interface *intf, pm_message_t message)
505{
506 int ret = -ENODEV;
507 struct usbnet *dev = usb_get_intfdata(intf);
508 struct cdc_mbim_state *info = (void *)&dev->data;
509 struct cdc_ncm_ctx *ctx = info->ctx;
510
511 if (!ctx)
512 goto error;
513
514 /*
515 * Both usbnet_suspend() and subdriver->suspend() MUST return 0
516 * in system sleep context, otherwise, the resume callback has
517 * to recover device from previous suspend failure.
518 */
519 ret = usbnet_suspend(intf, message);
520 if (ret < 0)
521 goto error;
522
523 if (intf == ctx->control && info->subdriver && info->subdriver->suspend)
524 ret = info->subdriver->suspend(intf, message);
525 if (ret < 0)
526 usbnet_resume(intf);
527
528error:
529 return ret;
530}
531
532static int cdc_mbim_resume(struct usb_interface *intf)
533{
534 int ret = 0;
535 struct usbnet *dev = usb_get_intfdata(intf);
536 struct cdc_mbim_state *info = (void *)&dev->data;
537 struct cdc_ncm_ctx *ctx = info->ctx;
538 bool callsub = (intf == ctx->control && info->subdriver && info->subdriver->resume);
539
540 if (callsub)
541 ret = info->subdriver->resume(intf);
542 if (ret < 0)
543 goto err;
544 ret = usbnet_resume(intf);
545 if (ret < 0 && callsub)
546 info->subdriver->suspend(intf, PMSG_SUSPEND);
547err:
548 return ret;
549}
550
551static const struct driver_info cdc_mbim_info = {
552 .description = "CDC MBIM",
553 .flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN,
554 .bind = cdc_mbim_bind,
555 .unbind = cdc_mbim_unbind,
556 .manage_power = cdc_mbim_manage_power,
557 .rx_fixup = cdc_mbim_rx_fixup,
558 .tx_fixup = cdc_mbim_tx_fixup,
559};
560
561/* MBIM and NCM devices should not need a ZLP after NTBs with
562 * dwNtbOutMaxSize length. Nevertheless, a number of devices from
563 * different vendor IDs will fail unless we send ZLPs, forcing us
564 * to make this the default.
565 *
566 * This default may cause a performance penalty for spec conforming
567 * devices wanting to take advantage of optimizations possible without
568 * ZLPs. A whitelist is added in an attempt to avoid this for devices
569 * known to conform to the MBIM specification.
570 *
571 * All known devices supporting NCM compatibility mode are also
572 * conforming to the NCM and MBIM specifications. For this reason, the
573 * NCM subclass entry is also in the ZLP whitelist.
574 */
575static const struct driver_info cdc_mbim_info_zlp = {
576 .description = "CDC MBIM",
577 .flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN | FLAG_SEND_ZLP,
578 .bind = cdc_mbim_bind,
579 .unbind = cdc_mbim_unbind,
580 .manage_power = cdc_mbim_manage_power,
581 .rx_fixup = cdc_mbim_rx_fixup,
582 .tx_fixup = cdc_mbim_tx_fixup,
583};
584
585/* The spefication explicitly allows NDPs to be placed anywhere in the
586 * frame, but some devices fail unless the NDP is placed after the IP
587 * packets. Using the CDC_NCM_FLAG_NDP_TO_END flags to force this
588 * behaviour.
589 *
590 * Note: The current implementation of this feature restricts each NTB
591 * to a single NDP, implying that multiplexed sessions cannot share an
592 * NTB. This might affect performace for multiplexed sessions.
593 */
594static const struct driver_info cdc_mbim_info_ndp_to_end = {
595 .description = "CDC MBIM",
596 .flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN,
597 .bind = cdc_mbim_bind,
598 .unbind = cdc_mbim_unbind,
599 .manage_power = cdc_mbim_manage_power,
600 .rx_fixup = cdc_mbim_rx_fixup,
601 .tx_fixup = cdc_mbim_tx_fixup,
602 .data = CDC_NCM_FLAG_NDP_TO_END,
603};
604
605static const struct usb_device_id mbim_devs[] = {
606 /* This duplicate NCM entry is intentional. MBIM devices can
607 * be disguised as NCM by default, and this is necessary to
608 * allow us to bind the correct driver_info to such devices.
609 *
610 * bind() will sort out this for us, selecting the correct
611 * entry and reject the other
612 */
613 { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_NCM, USB_CDC_PROTO_NONE),
614 .driver_info = (unsigned long)&cdc_mbim_info,
615 },
616 /* ZLP conformance whitelist: All Ericsson MBIM devices */
617 { USB_VENDOR_AND_INTERFACE_INFO(0x0bdb, USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
618 .driver_info = (unsigned long)&cdc_mbim_info,
619 },
620
621 /* Some Huawei devices, ME906s-158 (12d1:15c1) and E3372
622 * (12d1:157d), are known to fail unless the NDP is placed
623 * after the IP packets. Applying the quirk to all Huawei
624 * devices is broader than necessary, but harmless.
625 */
626 { USB_VENDOR_AND_INTERFACE_INFO(0x12d1, USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
627 .driver_info = (unsigned long)&cdc_mbim_info_ndp_to_end,
628 },
629 /* default entry */
630 { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_MBIM, USB_CDC_PROTO_NONE),
631 .driver_info = (unsigned long)&cdc_mbim_info_zlp,
632 },
633 {
634 },
635};
636MODULE_DEVICE_TABLE(usb, mbim_devs);
637
638static struct usb_driver cdc_mbim_driver = {
639 .name = "cdc_mbim",
640 .id_table = mbim_devs,
641 .probe = usbnet_probe,
642 .disconnect = usbnet_disconnect,
643 .suspend = cdc_mbim_suspend,
644 .resume = cdc_mbim_resume,
645 .reset_resume = cdc_mbim_resume,
646 .supports_autosuspend = 1,
647 .disable_hub_initiated_lpm = 1,
648};
649module_usb_driver(cdc_mbim_driver);
650
651MODULE_AUTHOR("Greg Suarez <gsuarez@smithmicro.com>");
652MODULE_AUTHOR("Bjørn Mork <bjorn@mork.no>");
653MODULE_DESCRIPTION("USB CDC MBIM host driver");
654MODULE_LICENSE("GPL");