1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 Copyright (c) 2011,2012 Intel Corp.
4
5 */
6
7 #include <net/bluetooth/bluetooth.h>
8 #include <net/bluetooth/hci.h>
9 #include <net/bluetooth/hci_core.h>
10 #include <crypto/hash.h>
11
12 #include "hci_request.h"
13 #include "a2mp.h"
14 #include "amp.h"
15
16 /* Remote AMP Controllers interface */
amp_ctrl_get(struct amp_ctrl * ctrl)17 void amp_ctrl_get(struct amp_ctrl *ctrl)
18 {
19 BT_DBG("ctrl %p orig refcnt %d", ctrl,
20 kref_read(&ctrl->kref));
21
22 kref_get(&ctrl->kref);
23 }
24
amp_ctrl_destroy(struct kref * kref)25 static void amp_ctrl_destroy(struct kref *kref)
26 {
27 struct amp_ctrl *ctrl = container_of(kref, struct amp_ctrl, kref);
28
29 BT_DBG("ctrl %p", ctrl);
30
31 kfree(ctrl->assoc);
32 kfree(ctrl);
33 }
34
amp_ctrl_put(struct amp_ctrl * ctrl)35 int amp_ctrl_put(struct amp_ctrl *ctrl)
36 {
37 BT_DBG("ctrl %p orig refcnt %d", ctrl,
38 kref_read(&ctrl->kref));
39
40 return kref_put(&ctrl->kref, &_ctrl_destroy);
41 }
42
amp_ctrl_add(struct amp_mgr * mgr,u8 id)43 struct amp_ctrl *amp_ctrl_add(struct amp_mgr *mgr, u8 id)
44 {
45 struct amp_ctrl *ctrl;
46
47 ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
48 if (!ctrl)
49 return NULL;
50
51 kref_init(&ctrl->kref);
52 ctrl->id = id;
53
54 mutex_lock(&mgr->amp_ctrls_lock);
55 list_add(&ctrl->list, &mgr->amp_ctrls);
56 mutex_unlock(&mgr->amp_ctrls_lock);
57
58 BT_DBG("mgr %p ctrl %p", mgr, ctrl);
59
60 return ctrl;
61 }
62
amp_ctrl_list_flush(struct amp_mgr * mgr)63 void amp_ctrl_list_flush(struct amp_mgr *mgr)
64 {
65 struct amp_ctrl *ctrl, *n;
66
67 BT_DBG("mgr %p", mgr);
68
69 mutex_lock(&mgr->amp_ctrls_lock);
70 list_for_each_entry_safe(ctrl, n, &mgr->amp_ctrls, list) {
71 list_del(&ctrl->list);
72 amp_ctrl_put(ctrl);
73 }
74 mutex_unlock(&mgr->amp_ctrls_lock);
75 }
76
amp_ctrl_lookup(struct amp_mgr * mgr,u8 id)77 struct amp_ctrl *amp_ctrl_lookup(struct amp_mgr *mgr, u8 id)
78 {
79 struct amp_ctrl *ctrl;
80
81 BT_DBG("mgr %p id %u", mgr, id);
82
83 mutex_lock(&mgr->amp_ctrls_lock);
84 list_for_each_entry(ctrl, &mgr->amp_ctrls, list) {
85 if (ctrl->id == id) {
86 amp_ctrl_get(ctrl);
87 mutex_unlock(&mgr->amp_ctrls_lock);
88 return ctrl;
89 }
90 }
91 mutex_unlock(&mgr->amp_ctrls_lock);
92
93 return NULL;
94 }
95
96 /* Physical Link interface */
__next_handle(struct amp_mgr * mgr)97 static u8 __next_handle(struct amp_mgr *mgr)
98 {
99 if (++mgr->handle == 0)
100 mgr->handle = 1;
101
102 return mgr->handle;
103 }
104
phylink_add(struct hci_dev * hdev,struct amp_mgr * mgr,u8 remote_id,bool out)105 struct hci_conn *phylink_add(struct hci_dev *hdev, struct amp_mgr *mgr,
106 u8 remote_id, bool out)
107 {
108 bdaddr_t *dst = &mgr->l2cap_conn->hcon->dst;
109 struct hci_conn *hcon;
110 u8 role = out ? HCI_ROLE_MASTER : HCI_ROLE_SLAVE;
111
112 hcon = hci_conn_add(hdev, AMP_LINK, dst, role);
113 if (!hcon)
114 return NULL;
115
116 BT_DBG("hcon %p dst %pMR", hcon, dst);
117
118 hcon->state = BT_CONNECT;
119 hcon->attempt++;
120 hcon->handle = __next_handle(mgr);
121 hcon->remote_id = remote_id;
122 hcon->amp_mgr = amp_mgr_get(mgr);
123
124 return hcon;
125 }
126
127 /* AMP crypto key generation interface */
hmac_sha256(u8 * key,u8 ksize,char * plaintext,u8 psize,u8 * output)128 static int hmac_sha256(u8 *key, u8 ksize, char *plaintext, u8 psize, u8 *output)
129 {
130 struct crypto_shash *tfm;
131 struct shash_desc *shash;
132 int ret;
133
134 if (!ksize)
135 return -EINVAL;
136
137 tfm = crypto_alloc_shash("hmac(sha256)", 0, 0);
138 if (IS_ERR(tfm)) {
139 BT_DBG("crypto_alloc_ahash failed: err %ld", PTR_ERR(tfm));
140 return PTR_ERR(tfm);
141 }
142
143 ret = crypto_shash_setkey(tfm, key, ksize);
144 if (ret) {
145 BT_DBG("crypto_ahash_setkey failed: err %d", ret);
146 goto failed;
147 }
148
149 shash = kzalloc(sizeof(*shash) + crypto_shash_descsize(tfm),
150 GFP_KERNEL);
151 if (!shash) {
152 ret = -ENOMEM;
153 goto failed;
154 }
155
156 shash->tfm = tfm;
157
158 ret = crypto_shash_digest(shash, plaintext, psize, output);
159
160 kfree(shash);
161
162 failed:
163 crypto_free_shash(tfm);
164 return ret;
165 }
166
phylink_gen_key(struct hci_conn * conn,u8 * data,u8 * len,u8 * type)167 int phylink_gen_key(struct hci_conn *conn, u8 *data, u8 *len, u8 *type)
168 {
169 struct hci_dev *hdev = conn->hdev;
170 struct link_key *key;
171 u8 keybuf[HCI_AMP_LINK_KEY_SIZE];
172 u8 gamp_key[HCI_AMP_LINK_KEY_SIZE];
173 int err;
174
175 if (!hci_conn_check_link_mode(conn))
176 return -EACCES;
177
178 BT_DBG("conn %p key_type %d", conn, conn->key_type);
179
180 /* Legacy key */
181 if (conn->key_type < 3) {
182 bt_dev_err(hdev, "legacy key type %u", conn->key_type);
183 return -EACCES;
184 }
185
186 *type = conn->key_type;
187 *len = HCI_AMP_LINK_KEY_SIZE;
188
189 key = hci_find_link_key(hdev, &conn->dst);
190 if (!key) {
191 BT_DBG("No Link key for conn %p dst %pMR", conn, &conn->dst);
192 return -EACCES;
193 }
194
195 /* BR/EDR Link Key concatenated together with itself */
196 memcpy(&keybuf[0], key->val, HCI_LINK_KEY_SIZE);
197 memcpy(&keybuf[HCI_LINK_KEY_SIZE], key->val, HCI_LINK_KEY_SIZE);
198
199 /* Derive Generic AMP Link Key (gamp) */
200 err = hmac_sha256(keybuf, HCI_AMP_LINK_KEY_SIZE, "gamp", 4, gamp_key);
201 if (err) {
202 bt_dev_err(hdev, "could not derive Generic AMP Key: err %d", err);
203 return err;
204 }
205
206 if (conn->key_type == HCI_LK_DEBUG_COMBINATION) {
207 BT_DBG("Use Generic AMP Key (gamp)");
208 memcpy(data, gamp_key, HCI_AMP_LINK_KEY_SIZE);
209 return err;
210 }
211
212 /* Derive Dedicated AMP Link Key: "802b" is 802.11 PAL keyID */
213 return hmac_sha256(gamp_key, HCI_AMP_LINK_KEY_SIZE, "802b", 4, data);
214 }
215
read_local_amp_assoc_complete(struct hci_dev * hdev,u8 status,u16 opcode,struct sk_buff * skb)216 static void read_local_amp_assoc_complete(struct hci_dev *hdev, u8 status,
217 u16 opcode, struct sk_buff *skb)
218 {
219 struct hci_rp_read_local_amp_assoc *rp = (void *)skb->data;
220 struct amp_assoc *assoc = &hdev->loc_assoc;
221 size_t rem_len, frag_len;
222
223 BT_DBG("%s status 0x%2.2x", hdev->name, rp->status);
224
225 if (rp->status)
226 goto send_rsp;
227
228 frag_len = skb->len - sizeof(*rp);
229 rem_len = __le16_to_cpu(rp->rem_len);
230
231 if (rem_len > frag_len) {
232 BT_DBG("frag_len %zu rem_len %zu", frag_len, rem_len);
233
234 memcpy(assoc->data + assoc->offset, rp->frag, frag_len);
235 assoc->offset += frag_len;
236
237 /* Read other fragments */
238 amp_read_loc_assoc_frag(hdev, rp->phy_handle);
239
240 return;
241 }
242
243 memcpy(assoc->data + assoc->offset, rp->frag, rem_len);
244 assoc->len = assoc->offset + rem_len;
245 assoc->offset = 0;
246
247 send_rsp:
248 /* Send A2MP Rsp when all fragments are received */
249 a2mp_send_getampassoc_rsp(hdev, rp->status);
250 a2mp_send_create_phy_link_req(hdev, rp->status);
251 }
252
amp_read_loc_assoc_frag(struct hci_dev * hdev,u8 phy_handle)253 void amp_read_loc_assoc_frag(struct hci_dev *hdev, u8 phy_handle)
254 {
255 struct hci_cp_read_local_amp_assoc cp;
256 struct amp_assoc *loc_assoc = &hdev->loc_assoc;
257 struct hci_request req;
258 int err;
259
260 BT_DBG("%s handle %u", hdev->name, phy_handle);
261
262 cp.phy_handle = phy_handle;
263 cp.max_len = cpu_to_le16(hdev->amp_assoc_size);
264 cp.len_so_far = cpu_to_le16(loc_assoc->offset);
265
266 hci_req_init(&req, hdev);
267 hci_req_add(&req, HCI_OP_READ_LOCAL_AMP_ASSOC, sizeof(cp), &cp);
268 err = hci_req_run_skb(&req, read_local_amp_assoc_complete);
269 if (err < 0)
270 a2mp_send_getampassoc_rsp(hdev, A2MP_STATUS_INVALID_CTRL_ID);
271 }
272
amp_read_loc_assoc(struct hci_dev * hdev,struct amp_mgr * mgr)273 void amp_read_loc_assoc(struct hci_dev *hdev, struct amp_mgr *mgr)
274 {
275 struct hci_cp_read_local_amp_assoc cp;
276 struct hci_request req;
277 int err;
278
279 memset(&hdev->loc_assoc, 0, sizeof(struct amp_assoc));
280 memset(&cp, 0, sizeof(cp));
281
282 cp.max_len = cpu_to_le16(hdev->amp_assoc_size);
283
284 set_bit(READ_LOC_AMP_ASSOC, &mgr->state);
285 hci_req_init(&req, hdev);
286 hci_req_add(&req, HCI_OP_READ_LOCAL_AMP_ASSOC, sizeof(cp), &cp);
287 err = hci_req_run_skb(&req, read_local_amp_assoc_complete);
288 if (err < 0)
289 a2mp_send_getampassoc_rsp(hdev, A2MP_STATUS_INVALID_CTRL_ID);
290 }
291
amp_read_loc_assoc_final_data(struct hci_dev * hdev,struct hci_conn * hcon)292 void amp_read_loc_assoc_final_data(struct hci_dev *hdev,
293 struct hci_conn *hcon)
294 {
295 struct hci_cp_read_local_amp_assoc cp;
296 struct amp_mgr *mgr = hcon->amp_mgr;
297 struct hci_request req;
298 int err;
299
300 if (!mgr)
301 return;
302
303 cp.phy_handle = hcon->handle;
304 cp.len_so_far = cpu_to_le16(0);
305 cp.max_len = cpu_to_le16(hdev->amp_assoc_size);
306
307 set_bit(READ_LOC_AMP_ASSOC_FINAL, &mgr->state);
308
309 /* Read Local AMP Assoc final link information data */
310 hci_req_init(&req, hdev);
311 hci_req_add(&req, HCI_OP_READ_LOCAL_AMP_ASSOC, sizeof(cp), &cp);
312 err = hci_req_run_skb(&req, read_local_amp_assoc_complete);
313 if (err < 0)
314 a2mp_send_getampassoc_rsp(hdev, A2MP_STATUS_INVALID_CTRL_ID);
315 }
316
write_remote_amp_assoc_complete(struct hci_dev * hdev,u8 status,u16 opcode,struct sk_buff * skb)317 static void write_remote_amp_assoc_complete(struct hci_dev *hdev, u8 status,
318 u16 opcode, struct sk_buff *skb)
319 {
320 struct hci_rp_write_remote_amp_assoc *rp = (void *)skb->data;
321
322 BT_DBG("%s status 0x%2.2x phy_handle 0x%2.2x",
323 hdev->name, rp->status, rp->phy_handle);
324
325 if (rp->status)
326 return;
327
328 amp_write_rem_assoc_continue(hdev, rp->phy_handle);
329 }
330
331 /* Write AMP Assoc data fragments, returns true with last fragment written*/
amp_write_rem_assoc_frag(struct hci_dev * hdev,struct hci_conn * hcon)332 static bool amp_write_rem_assoc_frag(struct hci_dev *hdev,
333 struct hci_conn *hcon)
334 {
335 struct hci_cp_write_remote_amp_assoc *cp;
336 struct amp_mgr *mgr = hcon->amp_mgr;
337 struct amp_ctrl *ctrl;
338 struct hci_request req;
339 u16 frag_len, len;
340
341 ctrl = amp_ctrl_lookup(mgr, hcon->remote_id);
342 if (!ctrl)
343 return false;
344
345 if (!ctrl->assoc_rem_len) {
346 BT_DBG("all fragments are written");
347 ctrl->assoc_rem_len = ctrl->assoc_len;
348 ctrl->assoc_len_so_far = 0;
349
350 amp_ctrl_put(ctrl);
351 return true;
352 }
353
354 frag_len = min_t(u16, 248, ctrl->assoc_rem_len);
355 len = frag_len + sizeof(*cp);
356
357 cp = kzalloc(len, GFP_KERNEL);
358 if (!cp) {
359 amp_ctrl_put(ctrl);
360 return false;
361 }
362
363 BT_DBG("hcon %p ctrl %p frag_len %u assoc_len %u rem_len %u",
364 hcon, ctrl, frag_len, ctrl->assoc_len, ctrl->assoc_rem_len);
365
366 cp->phy_handle = hcon->handle;
367 cp->len_so_far = cpu_to_le16(ctrl->assoc_len_so_far);
368 cp->rem_len = cpu_to_le16(ctrl->assoc_rem_len);
369 memcpy(cp->frag, ctrl->assoc, frag_len);
370
371 ctrl->assoc_len_so_far += frag_len;
372 ctrl->assoc_rem_len -= frag_len;
373
374 amp_ctrl_put(ctrl);
375
376 hci_req_init(&req, hdev);
377 hci_req_add(&req, HCI_OP_WRITE_REMOTE_AMP_ASSOC, len, cp);
378 hci_req_run_skb(&req, write_remote_amp_assoc_complete);
379
380 kfree(cp);
381
382 return false;
383 }
384
amp_write_rem_assoc_continue(struct hci_dev * hdev,u8 handle)385 void amp_write_rem_assoc_continue(struct hci_dev *hdev, u8 handle)
386 {
387 struct hci_conn *hcon;
388
389 BT_DBG("%s phy handle 0x%2.2x", hdev->name, handle);
390
391 hcon = hci_conn_hash_lookup_handle(hdev, handle);
392 if (!hcon)
393 return;
394
395 /* Send A2MP create phylink rsp when all fragments are written */
396 if (amp_write_rem_assoc_frag(hdev, hcon))
397 a2mp_send_create_phy_link_rsp(hdev, 0);
398 }
399
amp_write_remote_assoc(struct hci_dev * hdev,u8 handle)400 void amp_write_remote_assoc(struct hci_dev *hdev, u8 handle)
401 {
402 struct hci_conn *hcon;
403
404 BT_DBG("%s phy handle 0x%2.2x", hdev->name, handle);
405
406 hcon = hci_conn_hash_lookup_handle(hdev, handle);
407 if (!hcon)
408 return;
409
410 BT_DBG("%s phy handle 0x%2.2x hcon %p", hdev->name, handle, hcon);
411
412 amp_write_rem_assoc_frag(hdev, hcon);
413 }
414
create_phylink_complete(struct hci_dev * hdev,u8 status,u16 opcode)415 static void create_phylink_complete(struct hci_dev *hdev, u8 status,
416 u16 opcode)
417 {
418 struct hci_cp_create_phy_link *cp;
419
420 BT_DBG("%s status 0x%2.2x", hdev->name, status);
421
422 cp = hci_sent_cmd_data(hdev, HCI_OP_CREATE_PHY_LINK);
423 if (!cp)
424 return;
425
426 hci_dev_lock(hdev);
427
428 if (status) {
429 struct hci_conn *hcon;
430
431 hcon = hci_conn_hash_lookup_handle(hdev, cp->phy_handle);
432 if (hcon)
433 hci_conn_del(hcon);
434 } else {
435 amp_write_remote_assoc(hdev, cp->phy_handle);
436 }
437
438 hci_dev_unlock(hdev);
439 }
440
amp_create_phylink(struct hci_dev * hdev,struct amp_mgr * mgr,struct hci_conn * hcon)441 void amp_create_phylink(struct hci_dev *hdev, struct amp_mgr *mgr,
442 struct hci_conn *hcon)
443 {
444 struct hci_cp_create_phy_link cp;
445 struct hci_request req;
446
447 cp.phy_handle = hcon->handle;
448
449 BT_DBG("%s hcon %p phy handle 0x%2.2x", hdev->name, hcon,
450 hcon->handle);
451
452 if (phylink_gen_key(mgr->l2cap_conn->hcon, cp.key, &cp.key_len,
453 &cp.key_type)) {
454 BT_DBG("Cannot create link key");
455 return;
456 }
457
458 hci_req_init(&req, hdev);
459 hci_req_add(&req, HCI_OP_CREATE_PHY_LINK, sizeof(cp), &cp);
460 hci_req_run(&req, create_phylink_complete);
461 }
462
accept_phylink_complete(struct hci_dev * hdev,u8 status,u16 opcode)463 static void accept_phylink_complete(struct hci_dev *hdev, u8 status,
464 u16 opcode)
465 {
466 struct hci_cp_accept_phy_link *cp;
467
468 BT_DBG("%s status 0x%2.2x", hdev->name, status);
469
470 if (status)
471 return;
472
473 cp = hci_sent_cmd_data(hdev, HCI_OP_ACCEPT_PHY_LINK);
474 if (!cp)
475 return;
476
477 amp_write_remote_assoc(hdev, cp->phy_handle);
478 }
479
amp_accept_phylink(struct hci_dev * hdev,struct amp_mgr * mgr,struct hci_conn * hcon)480 void amp_accept_phylink(struct hci_dev *hdev, struct amp_mgr *mgr,
481 struct hci_conn *hcon)
482 {
483 struct hci_cp_accept_phy_link cp;
484 struct hci_request req;
485
486 cp.phy_handle = hcon->handle;
487
488 BT_DBG("%s hcon %p phy handle 0x%2.2x", hdev->name, hcon,
489 hcon->handle);
490
491 if (phylink_gen_key(mgr->l2cap_conn->hcon, cp.key, &cp.key_len,
492 &cp.key_type)) {
493 BT_DBG("Cannot create link key");
494 return;
495 }
496
497 hci_req_init(&req, hdev);
498 hci_req_add(&req, HCI_OP_ACCEPT_PHY_LINK, sizeof(cp), &cp);
499 hci_req_run(&req, accept_phylink_complete);
500 }
501
amp_physical_cfm(struct hci_conn * bredr_hcon,struct hci_conn * hs_hcon)502 void amp_physical_cfm(struct hci_conn *bredr_hcon, struct hci_conn *hs_hcon)
503 {
504 struct hci_dev *bredr_hdev = hci_dev_hold(bredr_hcon->hdev);
505 struct amp_mgr *mgr = hs_hcon->amp_mgr;
506 struct l2cap_chan *bredr_chan;
507
508 BT_DBG("bredr_hcon %p hs_hcon %p mgr %p", bredr_hcon, hs_hcon, mgr);
509
510 if (!bredr_hdev || !mgr || !mgr->bredr_chan)
511 return;
512
513 bredr_chan = mgr->bredr_chan;
514
515 l2cap_chan_lock(bredr_chan);
516
517 set_bit(FLAG_EFS_ENABLE, &bredr_chan->flags);
518 bredr_chan->remote_amp_id = hs_hcon->remote_id;
519 bredr_chan->local_amp_id = hs_hcon->hdev->id;
520 bredr_chan->hs_hcon = hs_hcon;
521 bredr_chan->conn->mtu = hs_hcon->hdev->block_mtu;
522
523 __l2cap_physical_cfm(bredr_chan, 0);
524
525 l2cap_chan_unlock(bredr_chan);
526
527 hci_dev_put(bredr_hdev);
528 }
529
amp_create_logical_link(struct l2cap_chan * chan)530 void amp_create_logical_link(struct l2cap_chan *chan)
531 {
532 struct hci_conn *hs_hcon = chan->hs_hcon;
533 struct hci_cp_create_accept_logical_link cp;
534 struct hci_dev *hdev;
535
536 BT_DBG("chan %p hs_hcon %p dst %pMR", chan, hs_hcon,
537 &chan->conn->hcon->dst);
538
539 if (!hs_hcon)
540 return;
541
542 hdev = hci_dev_hold(chan->hs_hcon->hdev);
543 if (!hdev)
544 return;
545
546 cp.phy_handle = hs_hcon->handle;
547
548 cp.tx_flow_spec.id = chan->local_id;
549 cp.tx_flow_spec.stype = chan->local_stype;
550 cp.tx_flow_spec.msdu = cpu_to_le16(chan->local_msdu);
551 cp.tx_flow_spec.sdu_itime = cpu_to_le32(chan->local_sdu_itime);
552 cp.tx_flow_spec.acc_lat = cpu_to_le32(chan->local_acc_lat);
553 cp.tx_flow_spec.flush_to = cpu_to_le32(chan->local_flush_to);
554
555 cp.rx_flow_spec.id = chan->remote_id;
556 cp.rx_flow_spec.stype = chan->remote_stype;
557 cp.rx_flow_spec.msdu = cpu_to_le16(chan->remote_msdu);
558 cp.rx_flow_spec.sdu_itime = cpu_to_le32(chan->remote_sdu_itime);
559 cp.rx_flow_spec.acc_lat = cpu_to_le32(chan->remote_acc_lat);
560 cp.rx_flow_spec.flush_to = cpu_to_le32(chan->remote_flush_to);
561
562 if (hs_hcon->out)
563 hci_send_cmd(hdev, HCI_OP_CREATE_LOGICAL_LINK, sizeof(cp),
564 &cp);
565 else
566 hci_send_cmd(hdev, HCI_OP_ACCEPT_LOGICAL_LINK, sizeof(cp),
567 &cp);
568
569 hci_dev_put(hdev);
570 }
571
amp_disconnect_logical_link(struct hci_chan * hchan)572 void amp_disconnect_logical_link(struct hci_chan *hchan)
573 {
574 struct hci_conn *hcon = hchan->conn;
575 struct hci_cp_disconn_logical_link cp;
576
577 if (hcon->state != BT_CONNECTED) {
578 BT_DBG("hchan %p not connected", hchan);
579 return;
580 }
581
582 cp.log_handle = cpu_to_le16(hchan->handle);
583 hci_send_cmd(hcon->hdev, HCI_OP_DISCONN_LOGICAL_LINK, sizeof(cp), &cp);
584 }
585
amp_destroy_logical_link(struct hci_chan * hchan,u8 reason)586 void amp_destroy_logical_link(struct hci_chan *hchan, u8 reason)
587 {
588 BT_DBG("hchan %p", hchan);
589
590 hci_chan_del(hchan);
591 }
592