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25#include <linux/types.h>
26#include <linux/usb/ch9.h>
27#include <linux/random.h>
28#include "wusbhc.h"
29
30static void wusbhc_set_gtk_callback(struct urb *urb);
31static void wusbhc_gtk_rekey_done_work(struct work_struct *work);
32
33int wusbhc_sec_create(struct wusbhc *wusbhc)
34{
35 wusbhc->gtk.descr.bLength = sizeof(wusbhc->gtk.descr) + sizeof(wusbhc->gtk.data);
36 wusbhc->gtk.descr.bDescriptorType = USB_DT_KEY;
37 wusbhc->gtk.descr.bReserved = 0;
38
39 wusbhc->gtk_index = wusb_key_index(0, WUSB_KEY_INDEX_TYPE_GTK,
40 WUSB_KEY_INDEX_ORIGINATOR_HOST);
41
42 INIT_WORK(&wusbhc->gtk_rekey_done_work, wusbhc_gtk_rekey_done_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_done_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, 1000 );
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
187 return usb_control_msg(
188 usb_dev, usb_sndctrlpipe(usb_dev, 0),
189 USB_REQ_SET_DESCRIPTOR,
190 USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
191 USB_DT_KEY << 8 | wusbhc->gtk_index, 0,
192 &wusbhc->gtk.descr, wusbhc->gtk.descr.bLength,
193 1000);
194}
195
196
197
198int wusb_dev_sec_add(struct wusbhc *wusbhc,
199 struct usb_device *usb_dev, struct wusb_dev *wusb_dev)
200{
201 int result, bytes, secd_size;
202 struct device *dev = &usb_dev->dev;
203 struct usb_security_descriptor *secd;
204 const struct usb_encryption_descriptor *etd, *ccm1_etd = NULL;
205 const void *itr, *top;
206 char buf[64];
207
208 secd = kmalloc(sizeof(struct usb_security_descriptor), GFP_KERNEL);
209 if (secd == NULL) {
210 result = -ENOMEM;
211 goto out;
212 }
213
214 result = usb_get_descriptor(usb_dev, USB_DT_SECURITY,
215 0, secd, sizeof(struct usb_security_descriptor));
216 if (result < sizeof(secd)) {
217 dev_err(dev, "Can't read security descriptor or "
218 "not enough data: %d\n", result);
219 goto out;
220 }
221 secd_size = le16_to_cpu(secd->wTotalLength);
222 secd = krealloc(secd, secd_size, GFP_KERNEL);
223 if (secd == NULL) {
224 dev_err(dev, "Can't allocate space for security descriptors\n");
225 goto out;
226 }
227 result = usb_get_descriptor(usb_dev, USB_DT_SECURITY,
228 0, secd, secd_size);
229 if (result < secd_size) {
230 dev_err(dev, "Can't read security descriptor or "
231 "not enough data: %d\n", result);
232 goto out;
233 }
234 bytes = 0;
235 itr = &secd[1];
236 top = (void *)secd + result;
237 while (itr < top) {
238 etd = itr;
239 if (top - itr < sizeof(*etd)) {
240 dev_err(dev, "BUG: bad device security descriptor; "
241 "not enough data (%zu vs %zu bytes left)\n",
242 top - itr, sizeof(*etd));
243 break;
244 }
245 if (etd->bLength < sizeof(*etd)) {
246 dev_err(dev, "BUG: bad device encryption descriptor; "
247 "descriptor is too short "
248 "(%u vs %zu needed)\n",
249 etd->bLength, sizeof(*etd));
250 break;
251 }
252 itr += etd->bLength;
253 bytes += snprintf(buf + bytes, sizeof(buf) - bytes,
254 "%s (0x%02x/%02x) ",
255 wusb_et_name(etd->bEncryptionType),
256 etd->bEncryptionValue, etd->bAuthKeyIndex);
257 if (etd->bEncryptionType == USB_ENC_TYPE_CCM_1)
258 ccm1_etd = etd;
259 }
260
261
262
263 if (ccm1_etd == NULL) {
264 dev_err(dev, "WUSB device doesn't support CCM1 encryption, "
265 "can't use!\n");
266 result = -EINVAL;
267 goto out;
268 }
269 wusb_dev->ccm1_etd = *ccm1_etd;
270 dev_dbg(dev, "supported encryption: %s; using %s (0x%02x/%02x)\n",
271 buf, wusb_et_name(ccm1_etd->bEncryptionType),
272 ccm1_etd->bEncryptionValue, ccm1_etd->bAuthKeyIndex);
273 result = 0;
274out:
275 kfree(secd);
276 return result;
277}
278
279void wusb_dev_sec_rm(struct wusb_dev *wusb_dev)
280{
281
282}
283
284
285
286
287
288
289
290
291
292
293int wusb_dev_update_address(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev)
294{
295 int result = -ENOMEM;
296 struct usb_device *usb_dev = wusb_dev->usb_dev;
297 struct device *dev = &usb_dev->dev;
298 u8 new_address = wusb_dev->addr & 0x7F;
299
300
301 result = usb_control_msg(usb_dev, usb_sndctrlpipe(usb_dev, 0),
302 USB_REQ_SET_ADDRESS, 0,
303 0, 0, NULL, 0, 1000 );
304 if (result < 0) {
305 dev_err(dev, "auth failed: can't set address 0: %d\n",
306 result);
307 goto error_addr0;
308 }
309 result = wusb_set_dev_addr(wusbhc, wusb_dev, 0);
310 if (result < 0)
311 goto error_addr0;
312 usb_set_device_state(usb_dev, USB_STATE_DEFAULT);
313 usb_ep0_reinit(usb_dev);
314
315
316 result = usb_control_msg(usb_dev, usb_sndctrlpipe(usb_dev, 0),
317 USB_REQ_SET_ADDRESS, 0,
318 new_address, 0, NULL, 0,
319 1000 );
320 if (result < 0) {
321 dev_err(dev, "auth failed: can't set address %u: %d\n",
322 new_address, result);
323 goto error_addr;
324 }
325 result = wusb_set_dev_addr(wusbhc, wusb_dev, new_address);
326 if (result < 0)
327 goto error_addr;
328 usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
329 usb_ep0_reinit(usb_dev);
330 usb_dev->authenticated = 1;
331error_addr:
332error_addr0:
333 return result;
334}
335
336
337
338
339
340
341int wusb_dev_4way_handshake(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev,
342 struct wusb_ckhdid *ck)
343{
344 int result = -ENOMEM;
345 struct usb_device *usb_dev = wusb_dev->usb_dev;
346 struct device *dev = &usb_dev->dev;
347 u32 tkid;
348 __le32 tkid_le;
349 struct usb_handshake *hs;
350 struct aes_ccm_nonce ccm_n;
351 u8 mic[8];
352 struct wusb_keydvt_in keydvt_in;
353 struct wusb_keydvt_out keydvt_out;
354
355 hs = kzalloc(3*sizeof(hs[0]), GFP_KERNEL);
356 if (hs == NULL) {
357 dev_err(dev, "can't allocate handshake data\n");
358 goto error_kzalloc;
359 }
360
361
362
363 result = wusb_dev_set_encryption(usb_dev, 1);
364 if (result < 0)
365 goto error_dev_set_encryption;
366
367 tkid = wusbhc_next_tkid(wusbhc, wusb_dev);
368 tkid_le = cpu_to_le32(tkid);
369
370 hs[0].bMessageNumber = 1;
371 hs[0].bStatus = 0;
372 memcpy(hs[0].tTKID, &tkid_le, sizeof(hs[0].tTKID));
373 hs[0].bReserved = 0;
374 memcpy(hs[0].CDID, &wusb_dev->cdid, sizeof(hs[0].CDID));
375 get_random_bytes(&hs[0].nonce, sizeof(hs[0].nonce));
376 memset(hs[0].MIC, 0, sizeof(hs[0].MIC));
377
378 result = usb_control_msg(
379 usb_dev, usb_sndctrlpipe(usb_dev, 0),
380 USB_REQ_SET_HANDSHAKE,
381 USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
382 1, 0, &hs[0], sizeof(hs[0]), 1000 );
383 if (result < 0) {
384 dev_err(dev, "Handshake1: request failed: %d\n", result);
385 goto error_hs1;
386 }
387
388
389 result = usb_control_msg(
390 usb_dev, usb_rcvctrlpipe(usb_dev, 0),
391 USB_REQ_GET_HANDSHAKE,
392 USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
393 2, 0, &hs[1], sizeof(hs[1]), 1000 );
394 if (result < 0) {
395 dev_err(dev, "Handshake2: request failed: %d\n", result);
396 goto error_hs2;
397 }
398
399 result = -EINVAL;
400 if (hs[1].bMessageNumber != 2) {
401 dev_err(dev, "Handshake2 failed: bad message number %u\n",
402 hs[1].bMessageNumber);
403 goto error_hs2;
404 }
405 if (hs[1].bStatus != 0) {
406 dev_err(dev, "Handshake2 failed: bad status %u\n",
407 hs[1].bStatus);
408 goto error_hs2;
409 }
410 if (memcmp(hs[0].tTKID, hs[1].tTKID, sizeof(hs[0].tTKID))) {
411 dev_err(dev, "Handshake2 failed: TKID mismatch "
412 "(#1 0x%02x%02x%02x vs #2 0x%02x%02x%02x)\n",
413 hs[0].tTKID[0], hs[0].tTKID[1], hs[0].tTKID[2],
414 hs[1].tTKID[0], hs[1].tTKID[1], hs[1].tTKID[2]);
415 goto error_hs2;
416 }
417 if (memcmp(hs[0].CDID, hs[1].CDID, sizeof(hs[0].CDID))) {
418 dev_err(dev, "Handshake2 failed: CDID mismatch\n");
419 goto error_hs2;
420 }
421
422
423 memset(&ccm_n.sfn, 0, sizeof(ccm_n.sfn));
424 memcpy(ccm_n.tkid, &tkid_le, sizeof(ccm_n.tkid));
425 ccm_n.src_addr = wusbhc->uwb_rc->uwb_dev.dev_addr;
426 ccm_n.dest_addr.data[0] = wusb_dev->addr;
427 ccm_n.dest_addr.data[1] = 0;
428
429
430 memcpy(keydvt_in.hnonce, hs[0].nonce, sizeof(keydvt_in.hnonce));
431 memcpy(keydvt_in.dnonce, hs[1].nonce, sizeof(keydvt_in.dnonce));
432 result = wusb_key_derive(&keydvt_out, ck->data, &ccm_n, &keydvt_in);
433 if (result < 0) {
434 dev_err(dev, "Handshake2 failed: cannot derive keys: %d\n",
435 result);
436 goto error_hs2;
437 }
438
439
440 result = wusb_oob_mic(mic, keydvt_out.kck, &ccm_n, &hs[1]);
441 if (result < 0) {
442 dev_err(dev, "Handshake2 failed: cannot compute MIC: %d\n",
443 result);
444 goto error_hs2;
445 }
446
447 if (memcmp(hs[1].MIC, mic, sizeof(hs[1].MIC))) {
448 dev_err(dev, "Handshake2 failed: MIC mismatch\n");
449 goto error_hs2;
450 }
451
452
453 hs[2].bMessageNumber = 3;
454 hs[2].bStatus = 0;
455 memcpy(hs[2].tTKID, &tkid_le, sizeof(hs[2].tTKID));
456 hs[2].bReserved = 0;
457 memcpy(hs[2].CDID, &wusb_dev->cdid, sizeof(hs[2].CDID));
458 memcpy(hs[2].nonce, hs[0].nonce, sizeof(hs[2].nonce));
459 result = wusb_oob_mic(hs[2].MIC, keydvt_out.kck, &ccm_n, &hs[2]);
460 if (result < 0) {
461 dev_err(dev, "Handshake3 failed: cannot compute MIC: %d\n",
462 result);
463 goto error_hs2;
464 }
465
466 result = usb_control_msg(
467 usb_dev, usb_sndctrlpipe(usb_dev, 0),
468 USB_REQ_SET_HANDSHAKE,
469 USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
470 3, 0, &hs[2], sizeof(hs[2]), 1000 );
471 if (result < 0) {
472 dev_err(dev, "Handshake3: request failed: %d\n", result);
473 goto error_hs3;
474 }
475
476 result = wusbhc->set_ptk(wusbhc, wusb_dev->port_idx, tkid,
477 keydvt_out.ptk, sizeof(keydvt_out.ptk));
478 if (result < 0)
479 goto error_wusbhc_set_ptk;
480
481 result = wusb_dev_set_gtk(wusbhc, wusb_dev);
482 if (result < 0) {
483 dev_err(dev, "Set GTK for device: request failed: %d\n",
484 result);
485 goto error_wusbhc_set_gtk;
486 }
487
488
489 if (usb_dev->authenticated == 0) {
490 result = wusb_dev_update_address(wusbhc, wusb_dev);
491 if (result < 0)
492 goto error_dev_update_address;
493 }
494 result = 0;
495 dev_info(dev, "device authenticated\n");
496
497error_dev_update_address:
498error_wusbhc_set_gtk:
499error_wusbhc_set_ptk:
500error_hs3:
501error_hs2:
502error_hs1:
503 memset(hs, 0, 3*sizeof(hs[0]));
504 memset(&keydvt_out, 0, sizeof(keydvt_out));
505 memset(&keydvt_in, 0, sizeof(keydvt_in));
506 memset(&ccm_n, 0, sizeof(ccm_n));
507 memset(mic, 0, sizeof(mic));
508 if (result < 0)
509 wusb_dev_set_encryption(usb_dev, 0);
510error_dev_set_encryption:
511 kfree(hs);
512error_kzalloc:
513 return result;
514}
515
516
517
518
519
520static void wusbhc_gtk_rekey_done_work(struct work_struct *work)
521{
522 struct wusbhc *wusbhc = container_of(work, struct wusbhc, gtk_rekey_done_work);
523 size_t key_size = sizeof(wusbhc->gtk.data);
524
525 mutex_lock(&wusbhc->mutex);
526
527 if (--wusbhc->pending_set_gtks == 0)
528 wusbhc->set_gtk(wusbhc, wusbhc->gtk_tkid, &wusbhc->gtk.descr.bKeyData, key_size);
529
530 mutex_unlock(&wusbhc->mutex);
531}
532
533static void wusbhc_set_gtk_callback(struct urb *urb)
534{
535 struct wusbhc *wusbhc = urb->context;
536
537 queue_work(wusbd, &wusbhc->gtk_rekey_done_work);
538}
539
540
541
542
543
544
545
546
547
548
549
550
551void wusbhc_gtk_rekey(struct wusbhc *wusbhc)
552{
553 static const size_t key_size = sizeof(wusbhc->gtk.data);
554 int p;
555
556 wusbhc_generate_gtk(wusbhc);
557
558 for (p = 0; p < wusbhc->ports_max; p++) {
559 struct wusb_dev *wusb_dev;
560
561 wusb_dev = wusbhc->port[p].wusb_dev;
562 if (!wusb_dev || !wusb_dev->usb_dev || !wusb_dev->usb_dev->authenticated)
563 continue;
564
565 usb_fill_control_urb(wusb_dev->set_gtk_urb, wusb_dev->usb_dev,
566 usb_sndctrlpipe(wusb_dev->usb_dev, 0),
567 (void *)wusb_dev->set_gtk_req,
568 &wusbhc->gtk.descr, wusbhc->gtk.descr.bLength,
569 wusbhc_set_gtk_callback, wusbhc);
570 if (usb_submit_urb(wusb_dev->set_gtk_urb, GFP_KERNEL) == 0)
571 wusbhc->pending_set_gtks++;
572 }
573 if (wusbhc->pending_set_gtks == 0)
574 wusbhc->set_gtk(wusbhc, wusbhc->gtk_tkid, &wusbhc->gtk.descr.bKeyData, key_size);
575}
576