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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
37
38
39
40
41
42
43
44 wusbhc->wq_security = create_singlethread_workqueue("wusbd_security");
45 if (wusbhc->wq_security == NULL) {
46 pr_err("WUSB-core: Cannot create wusbd_security workqueue\n");
47 return -ENOMEM;
48 }
49
50 wusbhc->gtk.descr.bLength = sizeof(wusbhc->gtk.descr) +
51 sizeof(wusbhc->gtk.data);
52 wusbhc->gtk.descr.bDescriptorType = USB_DT_KEY;
53 wusbhc->gtk.descr.bReserved = 0;
54 wusbhc->gtk_index = 0;
55
56 INIT_WORK(&wusbhc->gtk_rekey_work, wusbhc_gtk_rekey_work);
57
58 return 0;
59}
60
61
62
63void wusbhc_sec_destroy(struct wusbhc *wusbhc)
64{
65 destroy_workqueue(wusbhc->wq_security);
66}
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81static u32 wusbhc_next_tkid(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev)
82{
83 u32 *tkid;
84 u32 addr;
85
86 if (wusb_dev == NULL) {
87 tkid = &wusbhc->gtk_tkid;
88 addr = 0;
89 } else {
90 tkid = &wusb_port_by_idx(wusbhc, wusb_dev->port_idx)->ptk_tkid;
91 addr = wusb_dev->addr & 0x7f;
92 }
93
94 *tkid = (addr << 8) | ((*tkid + 1) & 0xff);
95
96 return *tkid;
97}
98
99static void wusbhc_generate_gtk(struct wusbhc *wusbhc)
100{
101 const size_t key_size = sizeof(wusbhc->gtk.data);
102 u32 tkid;
103
104 tkid = wusbhc_next_tkid(wusbhc, NULL);
105
106 wusbhc->gtk.descr.tTKID[0] = (tkid >> 0) & 0xff;
107 wusbhc->gtk.descr.tTKID[1] = (tkid >> 8) & 0xff;
108 wusbhc->gtk.descr.tTKID[2] = (tkid >> 16) & 0xff;
109
110 get_random_bytes(wusbhc->gtk.descr.bKeyData, key_size);
111}
112
113
114
115
116
117
118
119
120
121int wusbhc_sec_start(struct wusbhc *wusbhc)
122{
123 const size_t key_size = sizeof(wusbhc->gtk.data);
124 int result;
125
126 wusbhc_generate_gtk(wusbhc);
127
128 result = wusbhc->set_gtk(wusbhc, wusbhc->gtk_tkid,
129 &wusbhc->gtk.descr.bKeyData, key_size);
130 if (result < 0)
131 dev_err(wusbhc->dev, "cannot set GTK for the host: %d\n",
132 result);
133
134 return result;
135}
136
137
138
139
140
141
142
143void wusbhc_sec_stop(struct wusbhc *wusbhc)
144{
145 cancel_work_sync(&wusbhc->gtk_rekey_work);
146}
147
148
149
150const char *wusb_et_name(u8 x)
151{
152 switch (x) {
153 case USB_ENC_TYPE_UNSECURE: return "unsecure";
154 case USB_ENC_TYPE_WIRED: return "wired";
155 case USB_ENC_TYPE_CCM_1: return "CCM-1";
156 case USB_ENC_TYPE_RSA_1: return "RSA-1";
157 default: return "unknown";
158 }
159}
160EXPORT_SYMBOL_GPL(wusb_et_name);
161
162
163
164
165
166
167
168static int wusb_dev_set_encryption(struct usb_device *usb_dev, int value)
169{
170 int result;
171 struct device *dev = &usb_dev->dev;
172 struct wusb_dev *wusb_dev = usb_dev->wusb_dev;
173
174 if (value) {
175 value = wusb_dev->ccm1_etd.bEncryptionValue;
176 } else {
177
178 value = 0;
179 }
180
181 result = usb_control_msg(usb_dev, usb_sndctrlpipe(usb_dev, 0),
182 USB_REQ_SET_ENCRYPTION,
183 USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
184 value, 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
185 if (result < 0)
186 dev_err(dev, "Can't set device's WUSB encryption to "
187 "%s (value %d): %d\n",
188 wusb_et_name(wusb_dev->ccm1_etd.bEncryptionType),
189 wusb_dev->ccm1_etd.bEncryptionValue, result);
190 return result;
191}
192
193
194
195
196
197
198static int wusb_dev_set_gtk(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev)
199{
200 struct usb_device *usb_dev = wusb_dev->usb_dev;
201 u8 key_index = wusb_key_index(wusbhc->gtk_index,
202 WUSB_KEY_INDEX_TYPE_GTK, WUSB_KEY_INDEX_ORIGINATOR_HOST);
203
204 return usb_control_msg(
205 usb_dev, usb_sndctrlpipe(usb_dev, 0),
206 USB_REQ_SET_DESCRIPTOR,
207 USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
208 USB_DT_KEY << 8 | key_index, 0,
209 &wusbhc->gtk.descr, wusbhc->gtk.descr.bLength,
210 USB_CTRL_SET_TIMEOUT);
211}
212
213
214
215int wusb_dev_sec_add(struct wusbhc *wusbhc,
216 struct usb_device *usb_dev, struct wusb_dev *wusb_dev)
217{
218 int result, bytes, secd_size;
219 struct device *dev = &usb_dev->dev;
220 struct usb_security_descriptor *secd, *new_secd;
221 const struct usb_encryption_descriptor *etd, *ccm1_etd = NULL;
222 const void *itr, *top;
223 char buf[64];
224
225 secd = kmalloc(sizeof(*secd), GFP_KERNEL);
226 if (secd == NULL) {
227 result = -ENOMEM;
228 goto out;
229 }
230
231 result = usb_get_descriptor(usb_dev, USB_DT_SECURITY,
232 0, secd, sizeof(*secd));
233 if (result < sizeof(*secd)) {
234 dev_err(dev, "Can't read security descriptor or "
235 "not enough data: %d\n", result);
236 goto out;
237 }
238 secd_size = le16_to_cpu(secd->wTotalLength);
239 new_secd = krealloc(secd, secd_size, GFP_KERNEL);
240 if (new_secd == NULL) {
241 dev_err(dev,
242 "Can't allocate space for security descriptors\n");
243 goto out;
244 }
245 secd = new_secd;
246 result = usb_get_descriptor(usb_dev, USB_DT_SECURITY,
247 0, secd, secd_size);
248 if (result < secd_size) {
249 dev_err(dev, "Can't read security descriptor or "
250 "not enough data: %d\n", result);
251 goto out;
252 }
253 bytes = 0;
254 itr = &secd[1];
255 top = (void *)secd + result;
256 while (itr < top) {
257 etd = itr;
258 if (top - itr < sizeof(*etd)) {
259 dev_err(dev, "BUG: bad device security descriptor; "
260 "not enough data (%zu vs %zu bytes left)\n",
261 top - itr, sizeof(*etd));
262 break;
263 }
264 if (etd->bLength < sizeof(*etd)) {
265 dev_err(dev, "BUG: bad device encryption descriptor; "
266 "descriptor is too short "
267 "(%u vs %zu needed)\n",
268 etd->bLength, sizeof(*etd));
269 break;
270 }
271 itr += etd->bLength;
272 bytes += snprintf(buf + bytes, sizeof(buf) - bytes,
273 "%s (0x%02x/%02x) ",
274 wusb_et_name(etd->bEncryptionType),
275 etd->bEncryptionValue, etd->bAuthKeyIndex);
276 if (etd->bEncryptionType == USB_ENC_TYPE_CCM_1)
277 ccm1_etd = etd;
278 }
279
280
281
282 if (ccm1_etd == NULL) {
283 dev_err(dev, "WUSB device doesn't support CCM1 encryption, "
284 "can't use!\n");
285 result = -EINVAL;
286 goto out;
287 }
288 wusb_dev->ccm1_etd = *ccm1_etd;
289 dev_dbg(dev, "supported encryption: %s; using %s (0x%02x/%02x)\n",
290 buf, wusb_et_name(ccm1_etd->bEncryptionType),
291 ccm1_etd->bEncryptionValue, ccm1_etd->bAuthKeyIndex);
292 result = 0;
293out:
294 kfree(secd);
295 return result;
296}
297
298void wusb_dev_sec_rm(struct wusb_dev *wusb_dev)
299{
300
301}
302
303
304
305
306
307
308
309
310
311
312int wusb_dev_update_address(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev)
313{
314 int result = -ENOMEM;
315 struct usb_device *usb_dev = wusb_dev->usb_dev;
316 struct device *dev = &usb_dev->dev;
317 u8 new_address = wusb_dev->addr & 0x7F;
318
319
320 result = usb_control_msg(usb_dev, usb_sndctrlpipe(usb_dev, 0),
321 USB_REQ_SET_ADDRESS,
322 USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
323 0, 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
324 if (result < 0) {
325 dev_err(dev, "auth failed: can't set address 0: %d\n",
326 result);
327 goto error_addr0;
328 }
329 result = wusb_set_dev_addr(wusbhc, wusb_dev, 0);
330 if (result < 0)
331 goto error_addr0;
332 usb_set_device_state(usb_dev, USB_STATE_DEFAULT);
333 usb_ep0_reinit(usb_dev);
334
335
336 result = usb_control_msg(usb_dev, usb_sndctrlpipe(usb_dev, 0),
337 USB_REQ_SET_ADDRESS,
338 USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
339 new_address, 0, NULL, 0,
340 USB_CTRL_SET_TIMEOUT);
341 if (result < 0) {
342 dev_err(dev, "auth failed: can't set address %u: %d\n",
343 new_address, result);
344 goto error_addr;
345 }
346 result = wusb_set_dev_addr(wusbhc, wusb_dev, new_address);
347 if (result < 0)
348 goto error_addr;
349 usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
350 usb_ep0_reinit(usb_dev);
351 usb_dev->authenticated = 1;
352error_addr:
353error_addr0:
354 return result;
355}
356
357
358
359
360
361
362int wusb_dev_4way_handshake(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev,
363 struct wusb_ckhdid *ck)
364{
365 int result = -ENOMEM;
366 struct usb_device *usb_dev = wusb_dev->usb_dev;
367 struct device *dev = &usb_dev->dev;
368 u32 tkid;
369 __le32 tkid_le;
370 struct usb_handshake *hs;
371 struct aes_ccm_nonce ccm_n;
372 u8 mic[8];
373 struct wusb_keydvt_in keydvt_in;
374 struct wusb_keydvt_out keydvt_out;
375
376 hs = kcalloc(3, sizeof(hs[0]), GFP_KERNEL);
377 if (hs == NULL) {
378 dev_err(dev, "can't allocate handshake data\n");
379 goto error_kzalloc;
380 }
381
382
383
384 result = wusb_dev_set_encryption(usb_dev, 1);
385 if (result < 0)
386 goto error_dev_set_encryption;
387
388 tkid = wusbhc_next_tkid(wusbhc, wusb_dev);
389 tkid_le = cpu_to_le32(tkid);
390
391 hs[0].bMessageNumber = 1;
392 hs[0].bStatus = 0;
393 memcpy(hs[0].tTKID, &tkid_le, sizeof(hs[0].tTKID));
394 hs[0].bReserved = 0;
395 memcpy(hs[0].CDID, &wusb_dev->cdid, sizeof(hs[0].CDID));
396 get_random_bytes(&hs[0].nonce, sizeof(hs[0].nonce));
397 memset(hs[0].MIC, 0, sizeof(hs[0].MIC));
398
399 result = usb_control_msg(
400 usb_dev, usb_sndctrlpipe(usb_dev, 0),
401 USB_REQ_SET_HANDSHAKE,
402 USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
403 1, 0, &hs[0], sizeof(hs[0]), USB_CTRL_SET_TIMEOUT);
404 if (result < 0) {
405 dev_err(dev, "Handshake1: request failed: %d\n", result);
406 goto error_hs1;
407 }
408
409
410 result = usb_control_msg(
411 usb_dev, usb_rcvctrlpipe(usb_dev, 0),
412 USB_REQ_GET_HANDSHAKE,
413 USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
414 2, 0, &hs[1], sizeof(hs[1]), USB_CTRL_GET_TIMEOUT);
415 if (result < 0) {
416 dev_err(dev, "Handshake2: request failed: %d\n", result);
417 goto error_hs2;
418 }
419
420 result = -EINVAL;
421 if (hs[1].bMessageNumber != 2) {
422 dev_err(dev, "Handshake2 failed: bad message number %u\n",
423 hs[1].bMessageNumber);
424 goto error_hs2;
425 }
426 if (hs[1].bStatus != 0) {
427 dev_err(dev, "Handshake2 failed: bad status %u\n",
428 hs[1].bStatus);
429 goto error_hs2;
430 }
431 if (memcmp(hs[0].tTKID, hs[1].tTKID, sizeof(hs[0].tTKID))) {
432 dev_err(dev, "Handshake2 failed: TKID mismatch "
433 "(#1 0x%02x%02x%02x vs #2 0x%02x%02x%02x)\n",
434 hs[0].tTKID[0], hs[0].tTKID[1], hs[0].tTKID[2],
435 hs[1].tTKID[0], hs[1].tTKID[1], hs[1].tTKID[2]);
436 goto error_hs2;
437 }
438 if (memcmp(hs[0].CDID, hs[1].CDID, sizeof(hs[0].CDID))) {
439 dev_err(dev, "Handshake2 failed: CDID mismatch\n");
440 goto error_hs2;
441 }
442
443
444 memset(&ccm_n.sfn, 0, sizeof(ccm_n.sfn));
445 memcpy(ccm_n.tkid, &tkid_le, sizeof(ccm_n.tkid));
446 ccm_n.src_addr = wusbhc->uwb_rc->uwb_dev.dev_addr;
447 ccm_n.dest_addr.data[0] = wusb_dev->addr;
448 ccm_n.dest_addr.data[1] = 0;
449
450
451 memcpy(keydvt_in.hnonce, hs[0].nonce, sizeof(keydvt_in.hnonce));
452 memcpy(keydvt_in.dnonce, hs[1].nonce, sizeof(keydvt_in.dnonce));
453 result = wusb_key_derive(&keydvt_out, ck->data, &ccm_n, &keydvt_in);
454 if (result < 0) {
455 dev_err(dev, "Handshake2 failed: cannot derive keys: %d\n",
456 result);
457 goto error_hs2;
458 }
459
460
461 result = wusb_oob_mic(mic, keydvt_out.kck, &ccm_n, &hs[1]);
462 if (result < 0) {
463 dev_err(dev, "Handshake2 failed: cannot compute MIC: %d\n",
464 result);
465 goto error_hs2;
466 }
467
468 if (memcmp(hs[1].MIC, mic, sizeof(hs[1].MIC))) {
469 dev_err(dev, "Handshake2 failed: MIC mismatch\n");
470 goto error_hs2;
471 }
472
473
474 hs[2].bMessageNumber = 3;
475 hs[2].bStatus = 0;
476 memcpy(hs[2].tTKID, &tkid_le, sizeof(hs[2].tTKID));
477 hs[2].bReserved = 0;
478 memcpy(hs[2].CDID, &wusb_dev->cdid, sizeof(hs[2].CDID));
479 memcpy(hs[2].nonce, hs[0].nonce, sizeof(hs[2].nonce));
480 result = wusb_oob_mic(hs[2].MIC, keydvt_out.kck, &ccm_n, &hs[2]);
481 if (result < 0) {
482 dev_err(dev, "Handshake3 failed: cannot compute MIC: %d\n",
483 result);
484 goto error_hs2;
485 }
486
487 result = usb_control_msg(
488 usb_dev, usb_sndctrlpipe(usb_dev, 0),
489 USB_REQ_SET_HANDSHAKE,
490 USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
491 3, 0, &hs[2], sizeof(hs[2]), USB_CTRL_SET_TIMEOUT);
492 if (result < 0) {
493 dev_err(dev, "Handshake3: request failed: %d\n", result);
494 goto error_hs3;
495 }
496
497 result = wusbhc->set_ptk(wusbhc, wusb_dev->port_idx, tkid,
498 keydvt_out.ptk, sizeof(keydvt_out.ptk));
499 if (result < 0)
500 goto error_wusbhc_set_ptk;
501
502 result = wusb_dev_set_gtk(wusbhc, wusb_dev);
503 if (result < 0) {
504 dev_err(dev, "Set GTK for device: request failed: %d\n",
505 result);
506 goto error_wusbhc_set_gtk;
507 }
508
509
510 if (usb_dev->authenticated == 0) {
511 result = wusb_dev_update_address(wusbhc, wusb_dev);
512 if (result < 0)
513 goto error_dev_update_address;
514 }
515 result = 0;
516 dev_info(dev, "device authenticated\n");
517
518error_dev_update_address:
519error_wusbhc_set_gtk:
520error_wusbhc_set_ptk:
521error_hs3:
522error_hs2:
523error_hs1:
524 memset(hs, 0, 3*sizeof(hs[0]));
525 memzero_explicit(&keydvt_out, sizeof(keydvt_out));
526 memzero_explicit(&keydvt_in, sizeof(keydvt_in));
527 memzero_explicit(&ccm_n, sizeof(ccm_n));
528 memzero_explicit(mic, sizeof(mic));
529 if (result < 0)
530 wusb_dev_set_encryption(usb_dev, 0);
531error_dev_set_encryption:
532 kfree(hs);
533error_kzalloc:
534 return result;
535}
536
537
538
539
540
541static void wusbhc_gtk_rekey_work(struct work_struct *work)
542{
543 struct wusbhc *wusbhc = container_of(work,
544 struct wusbhc, gtk_rekey_work);
545 size_t key_size = sizeof(wusbhc->gtk.data);
546 int port_idx;
547 struct wusb_dev *wusb_dev, *wusb_dev_next;
548 LIST_HEAD(rekey_list);
549
550 mutex_lock(&wusbhc->mutex);
551
552 wusbhc_generate_gtk(wusbhc);
553
554 wusbhc->gtk_index = (wusbhc->gtk_index + 1) % (WUSB_KEY_INDEX_MAX + 1);
555
556
557
558
559
560 for (port_idx = 0; port_idx < wusbhc->ports_max; port_idx++) {
561 wusb_dev = wusbhc->port[port_idx].wusb_dev;
562 if (!wusb_dev || !wusb_dev->usb_dev
563 || !wusb_dev->usb_dev->authenticated)
564 continue;
565
566 wusb_dev_get(wusb_dev);
567 list_add_tail(&wusb_dev->rekey_node, &rekey_list);
568 }
569 mutex_unlock(&wusbhc->mutex);
570
571
572 list_for_each_entry_safe(wusb_dev, wusb_dev_next, &rekey_list,
573 rekey_node) {
574 list_del_init(&wusb_dev->rekey_node);
575 dev_dbg(&wusb_dev->usb_dev->dev,
576 "%s: rekey device at port %d\n",
577 __func__, wusb_dev->port_idx);
578
579 if (wusb_dev_set_gtk(wusbhc, wusb_dev) < 0) {
580 dev_err(&wusb_dev->usb_dev->dev,
581 "%s: rekey device at port %d failed\n",
582 __func__, wusb_dev->port_idx);
583 }
584 wusb_dev_put(wusb_dev);
585 }
586
587
588 mutex_lock(&wusbhc->mutex);
589 wusbhc->set_gtk(wusbhc, wusbhc->gtk_tkid,
590 &wusbhc->gtk.descr.bKeyData, key_size);
591 mutex_unlock(&wusbhc->mutex);
592}
593
594
595
596
597
598
599
600
601
602
603
604
605void wusbhc_gtk_rekey(struct wusbhc *wusbhc)
606{
607
608
609
610
611
612
613
614 queue_work(wusbhc->wq_security, &wusbhc->gtk_rekey_work);
615}
616