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25#include <linux/types.h>
26#include <linux/slab.h>
27#include <linux/usb/ch9.h>
28#include <linux/random.h>
29#include <linux/export.h>
30#include "wusbhc.h"
31
32static void wusbhc_gtk_rekey_work(struct work_struct *work);
33
34int wusbhc_sec_create(struct wusbhc *wusbhc)
35{
36 wusbhc->gtk.descr.bLength = sizeof(wusbhc->gtk.descr) +
37 sizeof(wusbhc->gtk.data);
38 wusbhc->gtk.descr.bDescriptorType = USB_DT_KEY;
39 wusbhc->gtk.descr.bReserved = 0;
40 wusbhc->gtk_index = 0;
41
42 INIT_WORK(&wusbhc->gtk_rekey_work, wusbhc_gtk_rekey_work);
43
44 return 0;
45}
46
47
48
49void wusbhc_sec_destroy(struct wusbhc *wusbhc)
50{
51}
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66static u32 wusbhc_next_tkid(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev)
67{
68 u32 *tkid;
69 u32 addr;
70
71 if (wusb_dev == NULL) {
72 tkid = &wusbhc->gtk_tkid;
73 addr = 0;
74 } else {
75 tkid = &wusb_port_by_idx(wusbhc, wusb_dev->port_idx)->ptk_tkid;
76 addr = wusb_dev->addr & 0x7f;
77 }
78
79 *tkid = (addr << 8) | ((*tkid + 1) & 0xff);
80
81 return *tkid;
82}
83
84static void wusbhc_generate_gtk(struct wusbhc *wusbhc)
85{
86 const size_t key_size = sizeof(wusbhc->gtk.data);
87 u32 tkid;
88
89 tkid = wusbhc_next_tkid(wusbhc, NULL);
90
91 wusbhc->gtk.descr.tTKID[0] = (tkid >> 0) & 0xff;
92 wusbhc->gtk.descr.tTKID[1] = (tkid >> 8) & 0xff;
93 wusbhc->gtk.descr.tTKID[2] = (tkid >> 16) & 0xff;
94
95 get_random_bytes(wusbhc->gtk.descr.bKeyData, key_size);
96}
97
98
99
100
101
102
103
104
105
106int wusbhc_sec_start(struct wusbhc *wusbhc)
107{
108 const size_t key_size = sizeof(wusbhc->gtk.data);
109 int result;
110
111 wusbhc_generate_gtk(wusbhc);
112
113 result = wusbhc->set_gtk(wusbhc, wusbhc->gtk_tkid,
114 &wusbhc->gtk.descr.bKeyData, key_size);
115 if (result < 0)
116 dev_err(wusbhc->dev, "cannot set GTK for the host: %d\n",
117 result);
118
119 return result;
120}
121
122
123
124
125
126
127
128void wusbhc_sec_stop(struct wusbhc *wusbhc)
129{
130 cancel_work_sync(&wusbhc->gtk_rekey_work);
131}
132
133
134
135const char *wusb_et_name(u8 x)
136{
137 switch (x) {
138 case USB_ENC_TYPE_UNSECURE: return "unsecure";
139 case USB_ENC_TYPE_WIRED: return "wired";
140 case USB_ENC_TYPE_CCM_1: return "CCM-1";
141 case USB_ENC_TYPE_RSA_1: return "RSA-1";
142 default: return "unknown";
143 }
144}
145EXPORT_SYMBOL_GPL(wusb_et_name);
146
147
148
149
150
151
152
153static int wusb_dev_set_encryption(struct usb_device *usb_dev, int value)
154{
155 int result;
156 struct device *dev = &usb_dev->dev;
157 struct wusb_dev *wusb_dev = usb_dev->wusb_dev;
158
159 if (value) {
160 value = wusb_dev->ccm1_etd.bEncryptionValue;
161 } else {
162
163 value = 0;
164 }
165
166 result = usb_control_msg(usb_dev, usb_sndctrlpipe(usb_dev, 0),
167 USB_REQ_SET_ENCRYPTION,
168 USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
169 value, 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
170 if (result < 0)
171 dev_err(dev, "Can't set device's WUSB encryption to "
172 "%s (value %d): %d\n",
173 wusb_et_name(wusb_dev->ccm1_etd.bEncryptionType),
174 wusb_dev->ccm1_etd.bEncryptionValue, result);
175 return result;
176}
177
178
179
180
181
182
183static int wusb_dev_set_gtk(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev)
184{
185 struct usb_device *usb_dev = wusb_dev->usb_dev;
186 u8 key_index = wusb_key_index(wusbhc->gtk_index,
187 WUSB_KEY_INDEX_TYPE_GTK, WUSB_KEY_INDEX_ORIGINATOR_HOST);
188
189 return usb_control_msg(
190 usb_dev, usb_sndctrlpipe(usb_dev, 0),
191 USB_REQ_SET_DESCRIPTOR,
192 USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
193 USB_DT_KEY << 8 | key_index, 0,
194 &wusbhc->gtk.descr, wusbhc->gtk.descr.bLength,
195 USB_CTRL_SET_TIMEOUT);
196}
197
198
199
200int wusb_dev_sec_add(struct wusbhc *wusbhc,
201 struct usb_device *usb_dev, struct wusb_dev *wusb_dev)
202{
203 int result, bytes, secd_size;
204 struct device *dev = &usb_dev->dev;
205 struct usb_security_descriptor *secd, *new_secd;
206 const struct usb_encryption_descriptor *etd, *ccm1_etd = NULL;
207 const void *itr, *top;
208 char buf[64];
209
210 secd = kmalloc(sizeof(*secd), GFP_KERNEL);
211 if (secd == NULL) {
212 result = -ENOMEM;
213 goto out;
214 }
215
216 result = usb_get_descriptor(usb_dev, USB_DT_SECURITY,
217 0, secd, sizeof(*secd));
218 if (result < sizeof(*secd)) {
219 dev_err(dev, "Can't read security descriptor or "
220 "not enough data: %d\n", result);
221 goto out;
222 }
223 secd_size = le16_to_cpu(secd->wTotalLength);
224 new_secd = krealloc(secd, secd_size, GFP_KERNEL);
225 if (new_secd == NULL) {
226 dev_err(dev,
227 "Can't allocate space for security descriptors\n");
228 goto out;
229 }
230 secd = new_secd;
231 result = usb_get_descriptor(usb_dev, USB_DT_SECURITY,
232 0, secd, secd_size);
233 if (result < secd_size) {
234 dev_err(dev, "Can't read security descriptor or "
235 "not enough data: %d\n", result);
236 goto out;
237 }
238 bytes = 0;
239 itr = &secd[1];
240 top = (void *)secd + result;
241 while (itr < top) {
242 etd = itr;
243 if (top - itr < sizeof(*etd)) {
244 dev_err(dev, "BUG: bad device security descriptor; "
245 "not enough data (%zu vs %zu bytes left)\n",
246 top - itr, sizeof(*etd));
247 break;
248 }
249 if (etd->bLength < sizeof(*etd)) {
250 dev_err(dev, "BUG: bad device encryption descriptor; "
251 "descriptor is too short "
252 "(%u vs %zu needed)\n",
253 etd->bLength, sizeof(*etd));
254 break;
255 }
256 itr += etd->bLength;
257 bytes += snprintf(buf + bytes, sizeof(buf) - bytes,
258 "%s (0x%02x/%02x) ",
259 wusb_et_name(etd->bEncryptionType),
260 etd->bEncryptionValue, etd->bAuthKeyIndex);
261 if (etd->bEncryptionType == USB_ENC_TYPE_CCM_1)
262 ccm1_etd = etd;
263 }
264
265
266
267 if (ccm1_etd == NULL) {
268 dev_err(dev, "WUSB device doesn't support CCM1 encryption, "
269 "can't use!\n");
270 result = -EINVAL;
271 goto out;
272 }
273 wusb_dev->ccm1_etd = *ccm1_etd;
274 dev_dbg(dev, "supported encryption: %s; using %s (0x%02x/%02x)\n",
275 buf, wusb_et_name(ccm1_etd->bEncryptionType),
276 ccm1_etd->bEncryptionValue, ccm1_etd->bAuthKeyIndex);
277 result = 0;
278out:
279 kfree(secd);
280 return result;
281}
282
283void wusb_dev_sec_rm(struct wusb_dev *wusb_dev)
284{
285
286}
287
288
289
290
291
292
293
294
295
296
297int wusb_dev_update_address(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev)
298{
299 int result = -ENOMEM;
300 struct usb_device *usb_dev = wusb_dev->usb_dev;
301 struct device *dev = &usb_dev->dev;
302 u8 new_address = wusb_dev->addr & 0x7F;
303
304
305 result = usb_control_msg(usb_dev, usb_sndctrlpipe(usb_dev, 0),
306 USB_REQ_SET_ADDRESS,
307 USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
308 0, 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
309 if (result < 0) {
310 dev_err(dev, "auth failed: can't set address 0: %d\n",
311 result);
312 goto error_addr0;
313 }
314 result = wusb_set_dev_addr(wusbhc, wusb_dev, 0);
315 if (result < 0)
316 goto error_addr0;
317 usb_set_device_state(usb_dev, USB_STATE_DEFAULT);
318 usb_ep0_reinit(usb_dev);
319
320
321 result = usb_control_msg(usb_dev, usb_sndctrlpipe(usb_dev, 0),
322 USB_REQ_SET_ADDRESS,
323 USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
324 new_address, 0, NULL, 0,
325 USB_CTRL_SET_TIMEOUT);
326 if (result < 0) {
327 dev_err(dev, "auth failed: can't set address %u: %d\n",
328 new_address, result);
329 goto error_addr;
330 }
331 result = wusb_set_dev_addr(wusbhc, wusb_dev, new_address);
332 if (result < 0)
333 goto error_addr;
334 usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
335 usb_ep0_reinit(usb_dev);
336 usb_dev->authenticated = 1;
337error_addr:
338error_addr0:
339 return result;
340}
341
342
343
344
345
346
347int wusb_dev_4way_handshake(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev,
348 struct wusb_ckhdid *ck)
349{
350 int result = -ENOMEM;
351 struct usb_device *usb_dev = wusb_dev->usb_dev;
352 struct device *dev = &usb_dev->dev;
353 u32 tkid;
354 __le32 tkid_le;
355 struct usb_handshake *hs;
356 struct aes_ccm_nonce ccm_n;
357 u8 mic[8];
358 struct wusb_keydvt_in keydvt_in;
359 struct wusb_keydvt_out keydvt_out;
360
361 hs = kcalloc(3, sizeof(hs[0]), GFP_KERNEL);
362 if (hs == NULL) {
363 dev_err(dev, "can't allocate handshake data\n");
364 goto error_kzalloc;
365 }
366
367
368
369 result = wusb_dev_set_encryption(usb_dev, 1);
370 if (result < 0)
371 goto error_dev_set_encryption;
372
373 tkid = wusbhc_next_tkid(wusbhc, wusb_dev);
374 tkid_le = cpu_to_le32(tkid);
375
376 hs[0].bMessageNumber = 1;
377 hs[0].bStatus = 0;
378 memcpy(hs[0].tTKID, &tkid_le, sizeof(hs[0].tTKID));
379 hs[0].bReserved = 0;
380 memcpy(hs[0].CDID, &wusb_dev->cdid, sizeof(hs[0].CDID));
381 get_random_bytes(&hs[0].nonce, sizeof(hs[0].nonce));
382 memset(hs[0].MIC, 0, sizeof(hs[0].MIC));
383
384 result = usb_control_msg(
385 usb_dev, usb_sndctrlpipe(usb_dev, 0),
386 USB_REQ_SET_HANDSHAKE,
387 USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
388 1, 0, &hs[0], sizeof(hs[0]), USB_CTRL_SET_TIMEOUT);
389 if (result < 0) {
390 dev_err(dev, "Handshake1: request failed: %d\n", result);
391 goto error_hs1;
392 }
393
394
395 result = usb_control_msg(
396 usb_dev, usb_rcvctrlpipe(usb_dev, 0),
397 USB_REQ_GET_HANDSHAKE,
398 USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
399 2, 0, &hs[1], sizeof(hs[1]), USB_CTRL_GET_TIMEOUT);
400 if (result < 0) {
401 dev_err(dev, "Handshake2: request failed: %d\n", result);
402 goto error_hs2;
403 }
404
405 result = -EINVAL;
406 if (hs[1].bMessageNumber != 2) {
407 dev_err(dev, "Handshake2 failed: bad message number %u\n",
408 hs[1].bMessageNumber);
409 goto error_hs2;
410 }
411 if (hs[1].bStatus != 0) {
412 dev_err(dev, "Handshake2 failed: bad status %u\n",
413 hs[1].bStatus);
414 goto error_hs2;
415 }
416 if (memcmp(hs[0].tTKID, hs[1].tTKID, sizeof(hs[0].tTKID))) {
417 dev_err(dev, "Handshake2 failed: TKID mismatch "
418 "(#1 0x%02x%02x%02x vs #2 0x%02x%02x%02x)\n",
419 hs[0].tTKID[0], hs[0].tTKID[1], hs[0].tTKID[2],
420 hs[1].tTKID[0], hs[1].tTKID[1], hs[1].tTKID[2]);
421 goto error_hs2;
422 }
423 if (memcmp(hs[0].CDID, hs[1].CDID, sizeof(hs[0].CDID))) {
424 dev_err(dev, "Handshake2 failed: CDID mismatch\n");
425 goto error_hs2;
426 }
427
428
429 memset(&ccm_n.sfn, 0, sizeof(ccm_n.sfn));
430 memcpy(ccm_n.tkid, &tkid_le, sizeof(ccm_n.tkid));
431 ccm_n.src_addr = wusbhc->uwb_rc->uwb_dev.dev_addr;
432 ccm_n.dest_addr.data[0] = wusb_dev->addr;
433 ccm_n.dest_addr.data[1] = 0;
434
435
436 memcpy(keydvt_in.hnonce, hs[0].nonce, sizeof(keydvt_in.hnonce));
437 memcpy(keydvt_in.dnonce, hs[1].nonce, sizeof(keydvt_in.dnonce));
438 result = wusb_key_derive(&keydvt_out, ck->data, &ccm_n, &keydvt_in);
439 if (result < 0) {
440 dev_err(dev, "Handshake2 failed: cannot derive keys: %d\n",
441 result);
442 goto error_hs2;
443 }
444
445
446 result = wusb_oob_mic(mic, keydvt_out.kck, &ccm_n, &hs[1]);
447 if (result < 0) {
448 dev_err(dev, "Handshake2 failed: cannot compute MIC: %d\n",
449 result);
450 goto error_hs2;
451 }
452
453 if (memcmp(hs[1].MIC, mic, sizeof(hs[1].MIC))) {
454 dev_err(dev, "Handshake2 failed: MIC mismatch\n");
455 goto error_hs2;
456 }
457
458
459 hs[2].bMessageNumber = 3;
460 hs[2].bStatus = 0;
461 memcpy(hs[2].tTKID, &tkid_le, sizeof(hs[2].tTKID));
462 hs[2].bReserved = 0;
463 memcpy(hs[2].CDID, &wusb_dev->cdid, sizeof(hs[2].CDID));
464 memcpy(hs[2].nonce, hs[0].nonce, sizeof(hs[2].nonce));
465 result = wusb_oob_mic(hs[2].MIC, keydvt_out.kck, &ccm_n, &hs[2]);
466 if (result < 0) {
467 dev_err(dev, "Handshake3 failed: cannot compute MIC: %d\n",
468 result);
469 goto error_hs2;
470 }
471
472 result = usb_control_msg(
473 usb_dev, usb_sndctrlpipe(usb_dev, 0),
474 USB_REQ_SET_HANDSHAKE,
475 USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
476 3, 0, &hs[2], sizeof(hs[2]), USB_CTRL_SET_TIMEOUT);
477 if (result < 0) {
478 dev_err(dev, "Handshake3: request failed: %d\n", result);
479 goto error_hs3;
480 }
481
482 result = wusbhc->set_ptk(wusbhc, wusb_dev->port_idx, tkid,
483 keydvt_out.ptk, sizeof(keydvt_out.ptk));
484 if (result < 0)
485 goto error_wusbhc_set_ptk;
486
487 result = wusb_dev_set_gtk(wusbhc, wusb_dev);
488 if (result < 0) {
489 dev_err(dev, "Set GTK for device: request failed: %d\n",
490 result);
491 goto error_wusbhc_set_gtk;
492 }
493
494
495 if (usb_dev->authenticated == 0) {
496 result = wusb_dev_update_address(wusbhc, wusb_dev);
497 if (result < 0)
498 goto error_dev_update_address;
499 }
500 result = 0;
501 dev_info(dev, "device authenticated\n");
502
503error_dev_update_address:
504error_wusbhc_set_gtk:
505error_wusbhc_set_ptk:
506error_hs3:
507error_hs2:
508error_hs1:
509 memset(hs, 0, 3*sizeof(hs[0]));
510 memset(&keydvt_out, 0, sizeof(keydvt_out));
511 memset(&keydvt_in, 0, sizeof(keydvt_in));
512 memset(&ccm_n, 0, sizeof(ccm_n));
513 memset(mic, 0, sizeof(mic));
514 if (result < 0)
515 wusb_dev_set_encryption(usb_dev, 0);
516error_dev_set_encryption:
517 kfree(hs);
518error_kzalloc:
519 return result;
520}
521
522
523
524
525
526static void wusbhc_gtk_rekey_work(struct work_struct *work)
527{
528 struct wusbhc *wusbhc = container_of(work,
529 struct wusbhc, gtk_rekey_work);
530 size_t key_size = sizeof(wusbhc->gtk.data);
531 int port_idx;
532 struct wusb_dev *wusb_dev, *wusb_dev_next;
533 LIST_HEAD(rekey_list);
534
535 mutex_lock(&wusbhc->mutex);
536
537 wusbhc_generate_gtk(wusbhc);
538
539 wusbhc->gtk_index = (wusbhc->gtk_index + 1) % (WUSB_KEY_INDEX_MAX + 1);
540
541
542
543
544
545 for (port_idx = 0; port_idx < wusbhc->ports_max; port_idx++) {
546 wusb_dev = wusbhc->port[port_idx].wusb_dev;
547 if (!wusb_dev || !wusb_dev->usb_dev
548 || !wusb_dev->usb_dev->authenticated)
549 continue;
550
551 wusb_dev_get(wusb_dev);
552 list_add_tail(&wusb_dev->rekey_node, &rekey_list);
553 }
554 mutex_unlock(&wusbhc->mutex);
555
556
557 list_for_each_entry_safe(wusb_dev, wusb_dev_next, &rekey_list,
558 rekey_node) {
559 list_del_init(&wusb_dev->rekey_node);
560 dev_dbg(&wusb_dev->usb_dev->dev,
561 "%s: rekey device at port %d\n",
562 __func__, wusb_dev->port_idx);
563
564 if (wusb_dev_set_gtk(wusbhc, wusb_dev) < 0) {
565 dev_err(&wusb_dev->usb_dev->dev,
566 "%s: rekey device at port %d failed\n",
567 __func__, wusb_dev->port_idx);
568 }
569 wusb_dev_put(wusb_dev);
570 }
571
572
573 mutex_lock(&wusbhc->mutex);
574 wusbhc->set_gtk(wusbhc, wusbhc->gtk_tkid,
575 &wusbhc->gtk.descr.bKeyData, key_size);
576 mutex_unlock(&wusbhc->mutex);
577}
578
579
580
581
582
583
584
585
586
587
588
589
590void wusbhc_gtk_rekey(struct wusbhc *wusbhc)
591{
592
593
594
595
596
597
598
599 queue_work(wusbd, &wusbhc->gtk_rekey_work);
600}
601