xref: /openbmc/linux/net/bluetooth/hci_conn.c (revision 22d55f02)
1 /*
2    BlueZ - Bluetooth protocol stack for Linux
3    Copyright (c) 2000-2001, 2010, Code Aurora Forum. All rights reserved.
4 
5    Written 2000,2001 by Maxim Krasnyansky <maxk@qualcomm.com>
6 
7    This program is free software; you can redistribute it and/or modify
8    it under the terms of the GNU General Public License version 2 as
9    published by the Free Software Foundation;
10 
11    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
12    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
13    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
14    IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
15    CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
16    WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
17    ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
18    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
19 
20    ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
21    COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
22    SOFTWARE IS DISCLAIMED.
23 */
24 
25 /* Bluetooth HCI connection handling. */
26 
27 #include <linux/export.h>
28 #include <linux/debugfs.h>
29 
30 #include <net/bluetooth/bluetooth.h>
31 #include <net/bluetooth/hci_core.h>
32 #include <net/bluetooth/l2cap.h>
33 
34 #include "hci_request.h"
35 #include "smp.h"
36 #include "a2mp.h"
37 
38 struct sco_param {
39 	u16 pkt_type;
40 	u16 max_latency;
41 	u8  retrans_effort;
42 };
43 
44 static const struct sco_param esco_param_cvsd[] = {
45 	{ EDR_ESCO_MASK & ~ESCO_2EV3, 0x000a,	0x01 }, /* S3 */
46 	{ EDR_ESCO_MASK & ~ESCO_2EV3, 0x0007,	0x01 }, /* S2 */
47 	{ EDR_ESCO_MASK | ESCO_EV3,   0x0007,	0x01 }, /* S1 */
48 	{ EDR_ESCO_MASK | ESCO_HV3,   0xffff,	0x01 }, /* D1 */
49 	{ EDR_ESCO_MASK | ESCO_HV1,   0xffff,	0x01 }, /* D0 */
50 };
51 
52 static const struct sco_param sco_param_cvsd[] = {
53 	{ EDR_ESCO_MASK | ESCO_HV3,   0xffff,	0xff }, /* D1 */
54 	{ EDR_ESCO_MASK | ESCO_HV1,   0xffff,	0xff }, /* D0 */
55 };
56 
57 static const struct sco_param esco_param_msbc[] = {
58 	{ EDR_ESCO_MASK & ~ESCO_2EV3, 0x000d,	0x02 }, /* T2 */
59 	{ EDR_ESCO_MASK | ESCO_EV3,   0x0008,	0x02 }, /* T1 */
60 };
61 
62 /* This function requires the caller holds hdev->lock */
63 static void hci_connect_le_scan_cleanup(struct hci_conn *conn)
64 {
65 	struct hci_conn_params *params;
66 	struct hci_dev *hdev = conn->hdev;
67 	struct smp_irk *irk;
68 	bdaddr_t *bdaddr;
69 	u8 bdaddr_type;
70 
71 	bdaddr = &conn->dst;
72 	bdaddr_type = conn->dst_type;
73 
74 	/* Check if we need to convert to identity address */
75 	irk = hci_get_irk(hdev, bdaddr, bdaddr_type);
76 	if (irk) {
77 		bdaddr = &irk->bdaddr;
78 		bdaddr_type = irk->addr_type;
79 	}
80 
81 	params = hci_pend_le_action_lookup(&hdev->pend_le_conns, bdaddr,
82 					   bdaddr_type);
83 	if (!params || !params->explicit_connect)
84 		return;
85 
86 	/* The connection attempt was doing scan for new RPA, and is
87 	 * in scan phase. If params are not associated with any other
88 	 * autoconnect action, remove them completely. If they are, just unmark
89 	 * them as waiting for connection, by clearing explicit_connect field.
90 	 */
91 	params->explicit_connect = false;
92 
93 	list_del_init(&params->action);
94 
95 	switch (params->auto_connect) {
96 	case HCI_AUTO_CONN_EXPLICIT:
97 		hci_conn_params_del(hdev, bdaddr, bdaddr_type);
98 		/* return instead of break to avoid duplicate scan update */
99 		return;
100 	case HCI_AUTO_CONN_DIRECT:
101 	case HCI_AUTO_CONN_ALWAYS:
102 		list_add(&params->action, &hdev->pend_le_conns);
103 		break;
104 	case HCI_AUTO_CONN_REPORT:
105 		list_add(&params->action, &hdev->pend_le_reports);
106 		break;
107 	default:
108 		break;
109 	}
110 
111 	hci_update_background_scan(hdev);
112 }
113 
114 static void hci_conn_cleanup(struct hci_conn *conn)
115 {
116 	struct hci_dev *hdev = conn->hdev;
117 
118 	if (test_bit(HCI_CONN_PARAM_REMOVAL_PEND, &conn->flags))
119 		hci_conn_params_del(conn->hdev, &conn->dst, conn->dst_type);
120 
121 	hci_chan_list_flush(conn);
122 
123 	hci_conn_hash_del(hdev, conn);
124 
125 	if (hdev->notify)
126 		hdev->notify(hdev, HCI_NOTIFY_CONN_DEL);
127 
128 	hci_conn_del_sysfs(conn);
129 
130 	debugfs_remove_recursive(conn->debugfs);
131 
132 	hci_dev_put(hdev);
133 
134 	hci_conn_put(conn);
135 }
136 
137 static void le_scan_cleanup(struct work_struct *work)
138 {
139 	struct hci_conn *conn = container_of(work, struct hci_conn,
140 					     le_scan_cleanup);
141 	struct hci_dev *hdev = conn->hdev;
142 	struct hci_conn *c = NULL;
143 
144 	BT_DBG("%s hcon %p", hdev->name, conn);
145 
146 	hci_dev_lock(hdev);
147 
148 	/* Check that the hci_conn is still around */
149 	rcu_read_lock();
150 	list_for_each_entry_rcu(c, &hdev->conn_hash.list, list) {
151 		if (c == conn)
152 			break;
153 	}
154 	rcu_read_unlock();
155 
156 	if (c == conn) {
157 		hci_connect_le_scan_cleanup(conn);
158 		hci_conn_cleanup(conn);
159 	}
160 
161 	hci_dev_unlock(hdev);
162 	hci_dev_put(hdev);
163 	hci_conn_put(conn);
164 }
165 
166 static void hci_connect_le_scan_remove(struct hci_conn *conn)
167 {
168 	BT_DBG("%s hcon %p", conn->hdev->name, conn);
169 
170 	/* We can't call hci_conn_del/hci_conn_cleanup here since that
171 	 * could deadlock with another hci_conn_del() call that's holding
172 	 * hci_dev_lock and doing cancel_delayed_work_sync(&conn->disc_work).
173 	 * Instead, grab temporary extra references to the hci_dev and
174 	 * hci_conn and perform the necessary cleanup in a separate work
175 	 * callback.
176 	 */
177 
178 	hci_dev_hold(conn->hdev);
179 	hci_conn_get(conn);
180 
181 	/* Even though we hold a reference to the hdev, many other
182 	 * things might get cleaned up meanwhile, including the hdev's
183 	 * own workqueue, so we can't use that for scheduling.
184 	 */
185 	schedule_work(&conn->le_scan_cleanup);
186 }
187 
188 static void hci_acl_create_connection(struct hci_conn *conn)
189 {
190 	struct hci_dev *hdev = conn->hdev;
191 	struct inquiry_entry *ie;
192 	struct hci_cp_create_conn cp;
193 
194 	BT_DBG("hcon %p", conn);
195 
196 	conn->state = BT_CONNECT;
197 	conn->out = true;
198 	conn->role = HCI_ROLE_MASTER;
199 
200 	conn->attempt++;
201 
202 	conn->link_policy = hdev->link_policy;
203 
204 	memset(&cp, 0, sizeof(cp));
205 	bacpy(&cp.bdaddr, &conn->dst);
206 	cp.pscan_rep_mode = 0x02;
207 
208 	ie = hci_inquiry_cache_lookup(hdev, &conn->dst);
209 	if (ie) {
210 		if (inquiry_entry_age(ie) <= INQUIRY_ENTRY_AGE_MAX) {
211 			cp.pscan_rep_mode = ie->data.pscan_rep_mode;
212 			cp.pscan_mode     = ie->data.pscan_mode;
213 			cp.clock_offset   = ie->data.clock_offset |
214 					    cpu_to_le16(0x8000);
215 		}
216 
217 		memcpy(conn->dev_class, ie->data.dev_class, 3);
218 		if (ie->data.ssp_mode > 0)
219 			set_bit(HCI_CONN_SSP_ENABLED, &conn->flags);
220 	}
221 
222 	cp.pkt_type = cpu_to_le16(conn->pkt_type);
223 	if (lmp_rswitch_capable(hdev) && !(hdev->link_mode & HCI_LM_MASTER))
224 		cp.role_switch = 0x01;
225 	else
226 		cp.role_switch = 0x00;
227 
228 	hci_send_cmd(hdev, HCI_OP_CREATE_CONN, sizeof(cp), &cp);
229 }
230 
231 int hci_disconnect(struct hci_conn *conn, __u8 reason)
232 {
233 	BT_DBG("hcon %p", conn);
234 
235 	/* When we are master of an established connection and it enters
236 	 * the disconnect timeout, then go ahead and try to read the
237 	 * current clock offset.  Processing of the result is done
238 	 * within the event handling and hci_clock_offset_evt function.
239 	 */
240 	if (conn->type == ACL_LINK && conn->role == HCI_ROLE_MASTER &&
241 	    (conn->state == BT_CONNECTED || conn->state == BT_CONFIG)) {
242 		struct hci_dev *hdev = conn->hdev;
243 		struct hci_cp_read_clock_offset clkoff_cp;
244 
245 		clkoff_cp.handle = cpu_to_le16(conn->handle);
246 		hci_send_cmd(hdev, HCI_OP_READ_CLOCK_OFFSET, sizeof(clkoff_cp),
247 			     &clkoff_cp);
248 	}
249 
250 	return hci_abort_conn(conn, reason);
251 }
252 
253 static void hci_add_sco(struct hci_conn *conn, __u16 handle)
254 {
255 	struct hci_dev *hdev = conn->hdev;
256 	struct hci_cp_add_sco cp;
257 
258 	BT_DBG("hcon %p", conn);
259 
260 	conn->state = BT_CONNECT;
261 	conn->out = true;
262 
263 	conn->attempt++;
264 
265 	cp.handle   = cpu_to_le16(handle);
266 	cp.pkt_type = cpu_to_le16(conn->pkt_type);
267 
268 	hci_send_cmd(hdev, HCI_OP_ADD_SCO, sizeof(cp), &cp);
269 }
270 
271 bool hci_setup_sync(struct hci_conn *conn, __u16 handle)
272 {
273 	struct hci_dev *hdev = conn->hdev;
274 	struct hci_cp_setup_sync_conn cp;
275 	const struct sco_param *param;
276 
277 	BT_DBG("hcon %p", conn);
278 
279 	conn->state = BT_CONNECT;
280 	conn->out = true;
281 
282 	conn->attempt++;
283 
284 	cp.handle   = cpu_to_le16(handle);
285 
286 	cp.tx_bandwidth   = cpu_to_le32(0x00001f40);
287 	cp.rx_bandwidth   = cpu_to_le32(0x00001f40);
288 	cp.voice_setting  = cpu_to_le16(conn->setting);
289 
290 	switch (conn->setting & SCO_AIRMODE_MASK) {
291 	case SCO_AIRMODE_TRANSP:
292 		if (conn->attempt > ARRAY_SIZE(esco_param_msbc))
293 			return false;
294 		param = &esco_param_msbc[conn->attempt - 1];
295 		break;
296 	case SCO_AIRMODE_CVSD:
297 		if (lmp_esco_capable(conn->link)) {
298 			if (conn->attempt > ARRAY_SIZE(esco_param_cvsd))
299 				return false;
300 			param = &esco_param_cvsd[conn->attempt - 1];
301 		} else {
302 			if (conn->attempt > ARRAY_SIZE(sco_param_cvsd))
303 				return false;
304 			param = &sco_param_cvsd[conn->attempt - 1];
305 		}
306 		break;
307 	default:
308 		return false;
309 	}
310 
311 	cp.retrans_effort = param->retrans_effort;
312 	cp.pkt_type = __cpu_to_le16(param->pkt_type);
313 	cp.max_latency = __cpu_to_le16(param->max_latency);
314 
315 	if (hci_send_cmd(hdev, HCI_OP_SETUP_SYNC_CONN, sizeof(cp), &cp) < 0)
316 		return false;
317 
318 	return true;
319 }
320 
321 u8 hci_le_conn_update(struct hci_conn *conn, u16 min, u16 max, u16 latency,
322 		      u16 to_multiplier)
323 {
324 	struct hci_dev *hdev = conn->hdev;
325 	struct hci_conn_params *params;
326 	struct hci_cp_le_conn_update cp;
327 
328 	hci_dev_lock(hdev);
329 
330 	params = hci_conn_params_lookup(hdev, &conn->dst, conn->dst_type);
331 	if (params) {
332 		params->conn_min_interval = min;
333 		params->conn_max_interval = max;
334 		params->conn_latency = latency;
335 		params->supervision_timeout = to_multiplier;
336 	}
337 
338 	hci_dev_unlock(hdev);
339 
340 	memset(&cp, 0, sizeof(cp));
341 	cp.handle		= cpu_to_le16(conn->handle);
342 	cp.conn_interval_min	= cpu_to_le16(min);
343 	cp.conn_interval_max	= cpu_to_le16(max);
344 	cp.conn_latency		= cpu_to_le16(latency);
345 	cp.supervision_timeout	= cpu_to_le16(to_multiplier);
346 	cp.min_ce_len		= cpu_to_le16(0x0000);
347 	cp.max_ce_len		= cpu_to_le16(0x0000);
348 
349 	hci_send_cmd(hdev, HCI_OP_LE_CONN_UPDATE, sizeof(cp), &cp);
350 
351 	if (params)
352 		return 0x01;
353 
354 	return 0x00;
355 }
356 
357 void hci_le_start_enc(struct hci_conn *conn, __le16 ediv, __le64 rand,
358 		      __u8 ltk[16], __u8 key_size)
359 {
360 	struct hci_dev *hdev = conn->hdev;
361 	struct hci_cp_le_start_enc cp;
362 
363 	BT_DBG("hcon %p", conn);
364 
365 	memset(&cp, 0, sizeof(cp));
366 
367 	cp.handle = cpu_to_le16(conn->handle);
368 	cp.rand = rand;
369 	cp.ediv = ediv;
370 	memcpy(cp.ltk, ltk, key_size);
371 
372 	hci_send_cmd(hdev, HCI_OP_LE_START_ENC, sizeof(cp), &cp);
373 }
374 
375 /* Device _must_ be locked */
376 void hci_sco_setup(struct hci_conn *conn, __u8 status)
377 {
378 	struct hci_conn *sco = conn->link;
379 
380 	if (!sco)
381 		return;
382 
383 	BT_DBG("hcon %p", conn);
384 
385 	if (!status) {
386 		if (lmp_esco_capable(conn->hdev))
387 			hci_setup_sync(sco, conn->handle);
388 		else
389 			hci_add_sco(sco, conn->handle);
390 	} else {
391 		hci_connect_cfm(sco, status);
392 		hci_conn_del(sco);
393 	}
394 }
395 
396 static void hci_conn_timeout(struct work_struct *work)
397 {
398 	struct hci_conn *conn = container_of(work, struct hci_conn,
399 					     disc_work.work);
400 	int refcnt = atomic_read(&conn->refcnt);
401 
402 	BT_DBG("hcon %p state %s", conn, state_to_string(conn->state));
403 
404 	WARN_ON(refcnt < 0);
405 
406 	/* FIXME: It was observed that in pairing failed scenario, refcnt
407 	 * drops below 0. Probably this is because l2cap_conn_del calls
408 	 * l2cap_chan_del for each channel, and inside l2cap_chan_del conn is
409 	 * dropped. After that loop hci_chan_del is called which also drops
410 	 * conn. For now make sure that ACL is alive if refcnt is higher then 0,
411 	 * otherwise drop it.
412 	 */
413 	if (refcnt > 0)
414 		return;
415 
416 	/* LE connections in scanning state need special handling */
417 	if (conn->state == BT_CONNECT && conn->type == LE_LINK &&
418 	    test_bit(HCI_CONN_SCANNING, &conn->flags)) {
419 		hci_connect_le_scan_remove(conn);
420 		return;
421 	}
422 
423 	hci_abort_conn(conn, hci_proto_disconn_ind(conn));
424 }
425 
426 /* Enter sniff mode */
427 static void hci_conn_idle(struct work_struct *work)
428 {
429 	struct hci_conn *conn = container_of(work, struct hci_conn,
430 					     idle_work.work);
431 	struct hci_dev *hdev = conn->hdev;
432 
433 	BT_DBG("hcon %p mode %d", conn, conn->mode);
434 
435 	if (!lmp_sniff_capable(hdev) || !lmp_sniff_capable(conn))
436 		return;
437 
438 	if (conn->mode != HCI_CM_ACTIVE || !(conn->link_policy & HCI_LP_SNIFF))
439 		return;
440 
441 	if (lmp_sniffsubr_capable(hdev) && lmp_sniffsubr_capable(conn)) {
442 		struct hci_cp_sniff_subrate cp;
443 		cp.handle             = cpu_to_le16(conn->handle);
444 		cp.max_latency        = cpu_to_le16(0);
445 		cp.min_remote_timeout = cpu_to_le16(0);
446 		cp.min_local_timeout  = cpu_to_le16(0);
447 		hci_send_cmd(hdev, HCI_OP_SNIFF_SUBRATE, sizeof(cp), &cp);
448 	}
449 
450 	if (!test_and_set_bit(HCI_CONN_MODE_CHANGE_PEND, &conn->flags)) {
451 		struct hci_cp_sniff_mode cp;
452 		cp.handle       = cpu_to_le16(conn->handle);
453 		cp.max_interval = cpu_to_le16(hdev->sniff_max_interval);
454 		cp.min_interval = cpu_to_le16(hdev->sniff_min_interval);
455 		cp.attempt      = cpu_to_le16(4);
456 		cp.timeout      = cpu_to_le16(1);
457 		hci_send_cmd(hdev, HCI_OP_SNIFF_MODE, sizeof(cp), &cp);
458 	}
459 }
460 
461 static void hci_conn_auto_accept(struct work_struct *work)
462 {
463 	struct hci_conn *conn = container_of(work, struct hci_conn,
464 					     auto_accept_work.work);
465 
466 	hci_send_cmd(conn->hdev, HCI_OP_USER_CONFIRM_REPLY, sizeof(conn->dst),
467 		     &conn->dst);
468 }
469 
470 static void le_conn_timeout(struct work_struct *work)
471 {
472 	struct hci_conn *conn = container_of(work, struct hci_conn,
473 					     le_conn_timeout.work);
474 	struct hci_dev *hdev = conn->hdev;
475 
476 	BT_DBG("");
477 
478 	/* We could end up here due to having done directed advertising,
479 	 * so clean up the state if necessary. This should however only
480 	 * happen with broken hardware or if low duty cycle was used
481 	 * (which doesn't have a timeout of its own).
482 	 */
483 	if (conn->role == HCI_ROLE_SLAVE) {
484 		u8 enable = 0x00;
485 		hci_send_cmd(hdev, HCI_OP_LE_SET_ADV_ENABLE, sizeof(enable),
486 			     &enable);
487 		hci_le_conn_failed(conn, HCI_ERROR_ADVERTISING_TIMEOUT);
488 		return;
489 	}
490 
491 	hci_abort_conn(conn, HCI_ERROR_REMOTE_USER_TERM);
492 }
493 
494 struct hci_conn *hci_conn_add(struct hci_dev *hdev, int type, bdaddr_t *dst,
495 			      u8 role)
496 {
497 	struct hci_conn *conn;
498 
499 	BT_DBG("%s dst %pMR", hdev->name, dst);
500 
501 	conn = kzalloc(sizeof(*conn), GFP_KERNEL);
502 	if (!conn)
503 		return NULL;
504 
505 	bacpy(&conn->dst, dst);
506 	bacpy(&conn->src, &hdev->bdaddr);
507 	conn->hdev  = hdev;
508 	conn->type  = type;
509 	conn->role  = role;
510 	conn->mode  = HCI_CM_ACTIVE;
511 	conn->state = BT_OPEN;
512 	conn->auth_type = HCI_AT_GENERAL_BONDING;
513 	conn->io_capability = hdev->io_capability;
514 	conn->remote_auth = 0xff;
515 	conn->key_type = 0xff;
516 	conn->rssi = HCI_RSSI_INVALID;
517 	conn->tx_power = HCI_TX_POWER_INVALID;
518 	conn->max_tx_power = HCI_TX_POWER_INVALID;
519 
520 	set_bit(HCI_CONN_POWER_SAVE, &conn->flags);
521 	conn->disc_timeout = HCI_DISCONN_TIMEOUT;
522 
523 	if (conn->role == HCI_ROLE_MASTER)
524 		conn->out = true;
525 
526 	switch (type) {
527 	case ACL_LINK:
528 		conn->pkt_type = hdev->pkt_type & ACL_PTYPE_MASK;
529 		break;
530 	case LE_LINK:
531 		/* conn->src should reflect the local identity address */
532 		hci_copy_identity_address(hdev, &conn->src, &conn->src_type);
533 		break;
534 	case SCO_LINK:
535 		if (lmp_esco_capable(hdev))
536 			conn->pkt_type = (hdev->esco_type & SCO_ESCO_MASK) |
537 					(hdev->esco_type & EDR_ESCO_MASK);
538 		else
539 			conn->pkt_type = hdev->pkt_type & SCO_PTYPE_MASK;
540 		break;
541 	case ESCO_LINK:
542 		conn->pkt_type = hdev->esco_type & ~EDR_ESCO_MASK;
543 		break;
544 	}
545 
546 	skb_queue_head_init(&conn->data_q);
547 
548 	INIT_LIST_HEAD(&conn->chan_list);
549 
550 	INIT_DELAYED_WORK(&conn->disc_work, hci_conn_timeout);
551 	INIT_DELAYED_WORK(&conn->auto_accept_work, hci_conn_auto_accept);
552 	INIT_DELAYED_WORK(&conn->idle_work, hci_conn_idle);
553 	INIT_DELAYED_WORK(&conn->le_conn_timeout, le_conn_timeout);
554 	INIT_WORK(&conn->le_scan_cleanup, le_scan_cleanup);
555 
556 	atomic_set(&conn->refcnt, 0);
557 
558 	hci_dev_hold(hdev);
559 
560 	hci_conn_hash_add(hdev, conn);
561 	if (hdev->notify)
562 		hdev->notify(hdev, HCI_NOTIFY_CONN_ADD);
563 
564 	hci_conn_init_sysfs(conn);
565 
566 	return conn;
567 }
568 
569 int hci_conn_del(struct hci_conn *conn)
570 {
571 	struct hci_dev *hdev = conn->hdev;
572 
573 	BT_DBG("%s hcon %p handle %d", hdev->name, conn, conn->handle);
574 
575 	cancel_delayed_work_sync(&conn->disc_work);
576 	cancel_delayed_work_sync(&conn->auto_accept_work);
577 	cancel_delayed_work_sync(&conn->idle_work);
578 
579 	if (conn->type == ACL_LINK) {
580 		struct hci_conn *sco = conn->link;
581 		if (sco)
582 			sco->link = NULL;
583 
584 		/* Unacked frames */
585 		hdev->acl_cnt += conn->sent;
586 	} else if (conn->type == LE_LINK) {
587 		cancel_delayed_work(&conn->le_conn_timeout);
588 
589 		if (hdev->le_pkts)
590 			hdev->le_cnt += conn->sent;
591 		else
592 			hdev->acl_cnt += conn->sent;
593 	} else {
594 		struct hci_conn *acl = conn->link;
595 		if (acl) {
596 			acl->link = NULL;
597 			hci_conn_drop(acl);
598 		}
599 	}
600 
601 	if (conn->amp_mgr)
602 		amp_mgr_put(conn->amp_mgr);
603 
604 	skb_queue_purge(&conn->data_q);
605 
606 	/* Remove the connection from the list and cleanup its remaining
607 	 * state. This is a separate function since for some cases like
608 	 * BT_CONNECT_SCAN we *only* want the cleanup part without the
609 	 * rest of hci_conn_del.
610 	 */
611 	hci_conn_cleanup(conn);
612 
613 	return 0;
614 }
615 
616 struct hci_dev *hci_get_route(bdaddr_t *dst, bdaddr_t *src, uint8_t src_type)
617 {
618 	int use_src = bacmp(src, BDADDR_ANY);
619 	struct hci_dev *hdev = NULL, *d;
620 
621 	BT_DBG("%pMR -> %pMR", src, dst);
622 
623 	read_lock(&hci_dev_list_lock);
624 
625 	list_for_each_entry(d, &hci_dev_list, list) {
626 		if (!test_bit(HCI_UP, &d->flags) ||
627 		    hci_dev_test_flag(d, HCI_USER_CHANNEL) ||
628 		    d->dev_type != HCI_PRIMARY)
629 			continue;
630 
631 		/* Simple routing:
632 		 *   No source address - find interface with bdaddr != dst
633 		 *   Source address    - find interface with bdaddr == src
634 		 */
635 
636 		if (use_src) {
637 			bdaddr_t id_addr;
638 			u8 id_addr_type;
639 
640 			if (src_type == BDADDR_BREDR) {
641 				if (!lmp_bredr_capable(d))
642 					continue;
643 				bacpy(&id_addr, &d->bdaddr);
644 				id_addr_type = BDADDR_BREDR;
645 			} else {
646 				if (!lmp_le_capable(d))
647 					continue;
648 
649 				hci_copy_identity_address(d, &id_addr,
650 							  &id_addr_type);
651 
652 				/* Convert from HCI to three-value type */
653 				if (id_addr_type == ADDR_LE_DEV_PUBLIC)
654 					id_addr_type = BDADDR_LE_PUBLIC;
655 				else
656 					id_addr_type = BDADDR_LE_RANDOM;
657 			}
658 
659 			if (!bacmp(&id_addr, src) && id_addr_type == src_type) {
660 				hdev = d; break;
661 			}
662 		} else {
663 			if (bacmp(&d->bdaddr, dst)) {
664 				hdev = d; break;
665 			}
666 		}
667 	}
668 
669 	if (hdev)
670 		hdev = hci_dev_hold(hdev);
671 
672 	read_unlock(&hci_dev_list_lock);
673 	return hdev;
674 }
675 EXPORT_SYMBOL(hci_get_route);
676 
677 /* This function requires the caller holds hdev->lock */
678 void hci_le_conn_failed(struct hci_conn *conn, u8 status)
679 {
680 	struct hci_dev *hdev = conn->hdev;
681 	struct hci_conn_params *params;
682 
683 	params = hci_pend_le_action_lookup(&hdev->pend_le_conns, &conn->dst,
684 					   conn->dst_type);
685 	if (params && params->conn) {
686 		hci_conn_drop(params->conn);
687 		hci_conn_put(params->conn);
688 		params->conn = NULL;
689 	}
690 
691 	conn->state = BT_CLOSED;
692 
693 	/* If the status indicates successful cancellation of
694 	 * the attempt (i.e. Unkown Connection Id) there's no point of
695 	 * notifying failure since we'll go back to keep trying to
696 	 * connect. The only exception is explicit connect requests
697 	 * where a timeout + cancel does indicate an actual failure.
698 	 */
699 	if (status != HCI_ERROR_UNKNOWN_CONN_ID ||
700 	    (params && params->explicit_connect))
701 		mgmt_connect_failed(hdev, &conn->dst, conn->type,
702 				    conn->dst_type, status);
703 
704 	hci_connect_cfm(conn, status);
705 
706 	hci_conn_del(conn);
707 
708 	/* Since we may have temporarily stopped the background scanning in
709 	 * favor of connection establishment, we should restart it.
710 	 */
711 	hci_update_background_scan(hdev);
712 
713 	/* Re-enable advertising in case this was a failed connection
714 	 * attempt as a peripheral.
715 	 */
716 	hci_req_reenable_advertising(hdev);
717 }
718 
719 static void create_le_conn_complete(struct hci_dev *hdev, u8 status, u16 opcode)
720 {
721 	struct hci_conn *conn;
722 
723 	hci_dev_lock(hdev);
724 
725 	conn = hci_lookup_le_connect(hdev);
726 
727 	if (!status) {
728 		hci_connect_le_scan_cleanup(conn);
729 		goto done;
730 	}
731 
732 	bt_dev_err(hdev, "request failed to create LE connection: "
733 		   "status 0x%2.2x", status);
734 
735 	if (!conn)
736 		goto done;
737 
738 	hci_le_conn_failed(conn, status);
739 
740 done:
741 	hci_dev_unlock(hdev);
742 }
743 
744 static bool conn_use_rpa(struct hci_conn *conn)
745 {
746 	struct hci_dev *hdev = conn->hdev;
747 
748 	return hci_dev_test_flag(hdev, HCI_PRIVACY);
749 }
750 
751 static void set_ext_conn_params(struct hci_conn *conn,
752 				struct hci_cp_le_ext_conn_param *p)
753 {
754 	struct hci_dev *hdev = conn->hdev;
755 
756 	memset(p, 0, sizeof(*p));
757 
758 	/* Set window to be the same value as the interval to
759 	 * enable continuous scanning.
760 	 */
761 	p->scan_interval = cpu_to_le16(hdev->le_scan_interval);
762 	p->scan_window = p->scan_interval;
763 	p->conn_interval_min = cpu_to_le16(conn->le_conn_min_interval);
764 	p->conn_interval_max = cpu_to_le16(conn->le_conn_max_interval);
765 	p->conn_latency = cpu_to_le16(conn->le_conn_latency);
766 	p->supervision_timeout = cpu_to_le16(conn->le_supv_timeout);
767 	p->min_ce_len = cpu_to_le16(0x0000);
768 	p->max_ce_len = cpu_to_le16(0x0000);
769 }
770 
771 static void hci_req_add_le_create_conn(struct hci_request *req,
772 				       struct hci_conn *conn,
773 				       bdaddr_t *direct_rpa)
774 {
775 	struct hci_dev *hdev = conn->hdev;
776 	u8 own_addr_type;
777 
778 	/* If direct address was provided we use it instead of current
779 	 * address.
780 	 */
781 	if (direct_rpa) {
782 		if (bacmp(&req->hdev->random_addr, direct_rpa))
783 			hci_req_add(req, HCI_OP_LE_SET_RANDOM_ADDR, 6,
784 								direct_rpa);
785 
786 		/* direct address is always RPA */
787 		own_addr_type = ADDR_LE_DEV_RANDOM;
788 	} else {
789 		/* Update random address, but set require_privacy to false so
790 		 * that we never connect with an non-resolvable address.
791 		 */
792 		if (hci_update_random_address(req, false, conn_use_rpa(conn),
793 					      &own_addr_type))
794 			return;
795 	}
796 
797 	if (use_ext_conn(hdev)) {
798 		struct hci_cp_le_ext_create_conn *cp;
799 		struct hci_cp_le_ext_conn_param *p;
800 		u8 data[sizeof(*cp) + sizeof(*p) * 3];
801 		u32 plen;
802 
803 		cp = (void *) data;
804 		p = (void *) cp->data;
805 
806 		memset(cp, 0, sizeof(*cp));
807 
808 		bacpy(&cp->peer_addr, &conn->dst);
809 		cp->peer_addr_type = conn->dst_type;
810 		cp->own_addr_type = own_addr_type;
811 
812 		plen = sizeof(*cp);
813 
814 		if (scan_1m(hdev)) {
815 			cp->phys |= LE_SCAN_PHY_1M;
816 			set_ext_conn_params(conn, p);
817 
818 			p++;
819 			plen += sizeof(*p);
820 		}
821 
822 		if (scan_2m(hdev)) {
823 			cp->phys |= LE_SCAN_PHY_2M;
824 			set_ext_conn_params(conn, p);
825 
826 			p++;
827 			plen += sizeof(*p);
828 		}
829 
830 		if (scan_coded(hdev)) {
831 			cp->phys |= LE_SCAN_PHY_CODED;
832 			set_ext_conn_params(conn, p);
833 
834 			plen += sizeof(*p);
835 		}
836 
837 		hci_req_add(req, HCI_OP_LE_EXT_CREATE_CONN, plen, data);
838 
839 	} else {
840 		struct hci_cp_le_create_conn cp;
841 
842 		memset(&cp, 0, sizeof(cp));
843 
844 		/* Set window to be the same value as the interval to enable
845 		 * continuous scanning.
846 		 */
847 		cp.scan_interval = cpu_to_le16(hdev->le_scan_interval);
848 		cp.scan_window = cp.scan_interval;
849 
850 		bacpy(&cp.peer_addr, &conn->dst);
851 		cp.peer_addr_type = conn->dst_type;
852 		cp.own_address_type = own_addr_type;
853 		cp.conn_interval_min = cpu_to_le16(conn->le_conn_min_interval);
854 		cp.conn_interval_max = cpu_to_le16(conn->le_conn_max_interval);
855 		cp.conn_latency = cpu_to_le16(conn->le_conn_latency);
856 		cp.supervision_timeout = cpu_to_le16(conn->le_supv_timeout);
857 		cp.min_ce_len = cpu_to_le16(0x0000);
858 		cp.max_ce_len = cpu_to_le16(0x0000);
859 
860 		hci_req_add(req, HCI_OP_LE_CREATE_CONN, sizeof(cp), &cp);
861 	}
862 
863 	conn->state = BT_CONNECT;
864 	clear_bit(HCI_CONN_SCANNING, &conn->flags);
865 }
866 
867 static void hci_req_directed_advertising(struct hci_request *req,
868 					 struct hci_conn *conn)
869 {
870 	struct hci_dev *hdev = req->hdev;
871 	u8 own_addr_type;
872 	u8 enable;
873 
874 	if (ext_adv_capable(hdev)) {
875 		struct hci_cp_le_set_ext_adv_params cp;
876 		bdaddr_t random_addr;
877 
878 		/* Set require_privacy to false so that the remote device has a
879 		 * chance of identifying us.
880 		 */
881 		if (hci_get_random_address(hdev, false, conn_use_rpa(conn), NULL,
882 					   &own_addr_type, &random_addr) < 0)
883 			return;
884 
885 		memset(&cp, 0, sizeof(cp));
886 
887 		cp.evt_properties = cpu_to_le16(LE_LEGACY_ADV_DIRECT_IND);
888 		cp.own_addr_type = own_addr_type;
889 		cp.channel_map = hdev->le_adv_channel_map;
890 		cp.tx_power = HCI_TX_POWER_INVALID;
891 		cp.primary_phy = HCI_ADV_PHY_1M;
892 		cp.secondary_phy = HCI_ADV_PHY_1M;
893 		cp.handle = 0; /* Use instance 0 for directed adv */
894 		cp.own_addr_type = own_addr_type;
895 		cp.peer_addr_type = conn->dst_type;
896 		bacpy(&cp.peer_addr, &conn->dst);
897 
898 		hci_req_add(req, HCI_OP_LE_SET_EXT_ADV_PARAMS, sizeof(cp), &cp);
899 
900 		if (own_addr_type == ADDR_LE_DEV_RANDOM &&
901 		    bacmp(&random_addr, BDADDR_ANY) &&
902 		    bacmp(&random_addr, &hdev->random_addr)) {
903 			struct hci_cp_le_set_adv_set_rand_addr cp;
904 
905 			memset(&cp, 0, sizeof(cp));
906 
907 			cp.handle = 0;
908 			bacpy(&cp.bdaddr, &random_addr);
909 
910 			hci_req_add(req,
911 				    HCI_OP_LE_SET_ADV_SET_RAND_ADDR,
912 				    sizeof(cp), &cp);
913 		}
914 
915 		__hci_req_enable_ext_advertising(req);
916 	} else {
917 		struct hci_cp_le_set_adv_param cp;
918 
919 		/* Clear the HCI_LE_ADV bit temporarily so that the
920 		 * hci_update_random_address knows that it's safe to go ahead
921 		 * and write a new random address. The flag will be set back on
922 		 * as soon as the SET_ADV_ENABLE HCI command completes.
923 		 */
924 		hci_dev_clear_flag(hdev, HCI_LE_ADV);
925 
926 		/* Set require_privacy to false so that the remote device has a
927 		 * chance of identifying us.
928 		 */
929 		if (hci_update_random_address(req, false, conn_use_rpa(conn),
930 					      &own_addr_type) < 0)
931 			return;
932 
933 		memset(&cp, 0, sizeof(cp));
934 		cp.type = LE_ADV_DIRECT_IND;
935 		cp.own_address_type = own_addr_type;
936 		cp.direct_addr_type = conn->dst_type;
937 		bacpy(&cp.direct_addr, &conn->dst);
938 		cp.channel_map = hdev->le_adv_channel_map;
939 
940 		hci_req_add(req, HCI_OP_LE_SET_ADV_PARAM, sizeof(cp), &cp);
941 
942 		enable = 0x01;
943 		hci_req_add(req, HCI_OP_LE_SET_ADV_ENABLE, sizeof(enable),
944 			    &enable);
945 	}
946 
947 	conn->state = BT_CONNECT;
948 }
949 
950 struct hci_conn *hci_connect_le(struct hci_dev *hdev, bdaddr_t *dst,
951 				u8 dst_type, u8 sec_level, u16 conn_timeout,
952 				u8 role, bdaddr_t *direct_rpa)
953 {
954 	struct hci_conn_params *params;
955 	struct hci_conn *conn;
956 	struct smp_irk *irk;
957 	struct hci_request req;
958 	int err;
959 
960 	/* Let's make sure that le is enabled.*/
961 	if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED)) {
962 		if (lmp_le_capable(hdev))
963 			return ERR_PTR(-ECONNREFUSED);
964 
965 		return ERR_PTR(-EOPNOTSUPP);
966 	}
967 
968 	/* Since the controller supports only one LE connection attempt at a
969 	 * time, we return -EBUSY if there is any connection attempt running.
970 	 */
971 	if (hci_lookup_le_connect(hdev))
972 		return ERR_PTR(-EBUSY);
973 
974 	/* If there's already a connection object but it's not in
975 	 * scanning state it means it must already be established, in
976 	 * which case we can't do anything else except report a failure
977 	 * to connect.
978 	 */
979 	conn = hci_conn_hash_lookup_le(hdev, dst, dst_type);
980 	if (conn && !test_bit(HCI_CONN_SCANNING, &conn->flags)) {
981 		return ERR_PTR(-EBUSY);
982 	}
983 
984 	/* When given an identity address with existing identity
985 	 * resolving key, the connection needs to be established
986 	 * to a resolvable random address.
987 	 *
988 	 * Storing the resolvable random address is required here
989 	 * to handle connection failures. The address will later
990 	 * be resolved back into the original identity address
991 	 * from the connect request.
992 	 */
993 	irk = hci_find_irk_by_addr(hdev, dst, dst_type);
994 	if (irk && bacmp(&irk->rpa, BDADDR_ANY)) {
995 		dst = &irk->rpa;
996 		dst_type = ADDR_LE_DEV_RANDOM;
997 	}
998 
999 	if (conn) {
1000 		bacpy(&conn->dst, dst);
1001 	} else {
1002 		conn = hci_conn_add(hdev, LE_LINK, dst, role);
1003 		if (!conn)
1004 			return ERR_PTR(-ENOMEM);
1005 		hci_conn_hold(conn);
1006 		conn->pending_sec_level = sec_level;
1007 	}
1008 
1009 	conn->dst_type = dst_type;
1010 	conn->sec_level = BT_SECURITY_LOW;
1011 	conn->conn_timeout = conn_timeout;
1012 
1013 	hci_req_init(&req, hdev);
1014 
1015 	/* Disable advertising if we're active. For master role
1016 	 * connections most controllers will refuse to connect if
1017 	 * advertising is enabled, and for slave role connections we
1018 	 * anyway have to disable it in order to start directed
1019 	 * advertising.
1020 	 */
1021 	if (hci_dev_test_flag(hdev, HCI_LE_ADV)) {
1022 		u8 enable = 0x00;
1023 		hci_req_add(&req, HCI_OP_LE_SET_ADV_ENABLE, sizeof(enable),
1024 			    &enable);
1025 	}
1026 
1027 	/* If requested to connect as slave use directed advertising */
1028 	if (conn->role == HCI_ROLE_SLAVE) {
1029 		/* If we're active scanning most controllers are unable
1030 		 * to initiate advertising. Simply reject the attempt.
1031 		 */
1032 		if (hci_dev_test_flag(hdev, HCI_LE_SCAN) &&
1033 		    hdev->le_scan_type == LE_SCAN_ACTIVE) {
1034 			hci_req_purge(&req);
1035 			hci_conn_del(conn);
1036 			return ERR_PTR(-EBUSY);
1037 		}
1038 
1039 		hci_req_directed_advertising(&req, conn);
1040 		goto create_conn;
1041 	}
1042 
1043 	params = hci_conn_params_lookup(hdev, &conn->dst, conn->dst_type);
1044 	if (params) {
1045 		conn->le_conn_min_interval = params->conn_min_interval;
1046 		conn->le_conn_max_interval = params->conn_max_interval;
1047 		conn->le_conn_latency = params->conn_latency;
1048 		conn->le_supv_timeout = params->supervision_timeout;
1049 	} else {
1050 		conn->le_conn_min_interval = hdev->le_conn_min_interval;
1051 		conn->le_conn_max_interval = hdev->le_conn_max_interval;
1052 		conn->le_conn_latency = hdev->le_conn_latency;
1053 		conn->le_supv_timeout = hdev->le_supv_timeout;
1054 	}
1055 
1056 	/* If controller is scanning, we stop it since some controllers are
1057 	 * not able to scan and connect at the same time. Also set the
1058 	 * HCI_LE_SCAN_INTERRUPTED flag so that the command complete
1059 	 * handler for scan disabling knows to set the correct discovery
1060 	 * state.
1061 	 */
1062 	if (hci_dev_test_flag(hdev, HCI_LE_SCAN)) {
1063 		hci_req_add_le_scan_disable(&req);
1064 		hci_dev_set_flag(hdev, HCI_LE_SCAN_INTERRUPTED);
1065 	}
1066 
1067 	hci_req_add_le_create_conn(&req, conn, direct_rpa);
1068 
1069 create_conn:
1070 	err = hci_req_run(&req, create_le_conn_complete);
1071 	if (err) {
1072 		hci_conn_del(conn);
1073 		return ERR_PTR(err);
1074 	}
1075 
1076 	return conn;
1077 }
1078 
1079 static bool is_connected(struct hci_dev *hdev, bdaddr_t *addr, u8 type)
1080 {
1081 	struct hci_conn *conn;
1082 
1083 	conn = hci_conn_hash_lookup_le(hdev, addr, type);
1084 	if (!conn)
1085 		return false;
1086 
1087 	if (conn->state != BT_CONNECTED)
1088 		return false;
1089 
1090 	return true;
1091 }
1092 
1093 /* This function requires the caller holds hdev->lock */
1094 static int hci_explicit_conn_params_set(struct hci_dev *hdev,
1095 					bdaddr_t *addr, u8 addr_type)
1096 {
1097 	struct hci_conn_params *params;
1098 
1099 	if (is_connected(hdev, addr, addr_type))
1100 		return -EISCONN;
1101 
1102 	params = hci_conn_params_lookup(hdev, addr, addr_type);
1103 	if (!params) {
1104 		params = hci_conn_params_add(hdev, addr, addr_type);
1105 		if (!params)
1106 			return -ENOMEM;
1107 
1108 		/* If we created new params, mark them to be deleted in
1109 		 * hci_connect_le_scan_cleanup. It's different case than
1110 		 * existing disabled params, those will stay after cleanup.
1111 		 */
1112 		params->auto_connect = HCI_AUTO_CONN_EXPLICIT;
1113 	}
1114 
1115 	/* We're trying to connect, so make sure params are at pend_le_conns */
1116 	if (params->auto_connect == HCI_AUTO_CONN_DISABLED ||
1117 	    params->auto_connect == HCI_AUTO_CONN_REPORT ||
1118 	    params->auto_connect == HCI_AUTO_CONN_EXPLICIT) {
1119 		list_del_init(&params->action);
1120 		list_add(&params->action, &hdev->pend_le_conns);
1121 	}
1122 
1123 	params->explicit_connect = true;
1124 
1125 	BT_DBG("addr %pMR (type %u) auto_connect %u", addr, addr_type,
1126 	       params->auto_connect);
1127 
1128 	return 0;
1129 }
1130 
1131 /* This function requires the caller holds hdev->lock */
1132 struct hci_conn *hci_connect_le_scan(struct hci_dev *hdev, bdaddr_t *dst,
1133 				     u8 dst_type, u8 sec_level,
1134 				     u16 conn_timeout)
1135 {
1136 	struct hci_conn *conn;
1137 
1138 	/* Let's make sure that le is enabled.*/
1139 	if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED)) {
1140 		if (lmp_le_capable(hdev))
1141 			return ERR_PTR(-ECONNREFUSED);
1142 
1143 		return ERR_PTR(-EOPNOTSUPP);
1144 	}
1145 
1146 	/* Some devices send ATT messages as soon as the physical link is
1147 	 * established. To be able to handle these ATT messages, the user-
1148 	 * space first establishes the connection and then starts the pairing
1149 	 * process.
1150 	 *
1151 	 * So if a hci_conn object already exists for the following connection
1152 	 * attempt, we simply update pending_sec_level and auth_type fields
1153 	 * and return the object found.
1154 	 */
1155 	conn = hci_conn_hash_lookup_le(hdev, dst, dst_type);
1156 	if (conn) {
1157 		if (conn->pending_sec_level < sec_level)
1158 			conn->pending_sec_level = sec_level;
1159 		goto done;
1160 	}
1161 
1162 	BT_DBG("requesting refresh of dst_addr");
1163 
1164 	conn = hci_conn_add(hdev, LE_LINK, dst, HCI_ROLE_MASTER);
1165 	if (!conn)
1166 		return ERR_PTR(-ENOMEM);
1167 
1168 	if (hci_explicit_conn_params_set(hdev, dst, dst_type) < 0)
1169 		return ERR_PTR(-EBUSY);
1170 
1171 	conn->state = BT_CONNECT;
1172 	set_bit(HCI_CONN_SCANNING, &conn->flags);
1173 	conn->dst_type = dst_type;
1174 	conn->sec_level = BT_SECURITY_LOW;
1175 	conn->pending_sec_level = sec_level;
1176 	conn->conn_timeout = conn_timeout;
1177 
1178 	hci_update_background_scan(hdev);
1179 
1180 done:
1181 	hci_conn_hold(conn);
1182 	return conn;
1183 }
1184 
1185 struct hci_conn *hci_connect_acl(struct hci_dev *hdev, bdaddr_t *dst,
1186 				 u8 sec_level, u8 auth_type)
1187 {
1188 	struct hci_conn *acl;
1189 
1190 	if (!hci_dev_test_flag(hdev, HCI_BREDR_ENABLED)) {
1191 		if (lmp_bredr_capable(hdev))
1192 			return ERR_PTR(-ECONNREFUSED);
1193 
1194 		return ERR_PTR(-EOPNOTSUPP);
1195 	}
1196 
1197 	acl = hci_conn_hash_lookup_ba(hdev, ACL_LINK, dst);
1198 	if (!acl) {
1199 		acl = hci_conn_add(hdev, ACL_LINK, dst, HCI_ROLE_MASTER);
1200 		if (!acl)
1201 			return ERR_PTR(-ENOMEM);
1202 	}
1203 
1204 	hci_conn_hold(acl);
1205 
1206 	if (acl->state == BT_OPEN || acl->state == BT_CLOSED) {
1207 		acl->sec_level = BT_SECURITY_LOW;
1208 		acl->pending_sec_level = sec_level;
1209 		acl->auth_type = auth_type;
1210 		hci_acl_create_connection(acl);
1211 	}
1212 
1213 	return acl;
1214 }
1215 
1216 struct hci_conn *hci_connect_sco(struct hci_dev *hdev, int type, bdaddr_t *dst,
1217 				 __u16 setting)
1218 {
1219 	struct hci_conn *acl;
1220 	struct hci_conn *sco;
1221 
1222 	acl = hci_connect_acl(hdev, dst, BT_SECURITY_LOW, HCI_AT_NO_BONDING);
1223 	if (IS_ERR(acl))
1224 		return acl;
1225 
1226 	sco = hci_conn_hash_lookup_ba(hdev, type, dst);
1227 	if (!sco) {
1228 		sco = hci_conn_add(hdev, type, dst, HCI_ROLE_MASTER);
1229 		if (!sco) {
1230 			hci_conn_drop(acl);
1231 			return ERR_PTR(-ENOMEM);
1232 		}
1233 	}
1234 
1235 	acl->link = sco;
1236 	sco->link = acl;
1237 
1238 	hci_conn_hold(sco);
1239 
1240 	sco->setting = setting;
1241 
1242 	if (acl->state == BT_CONNECTED &&
1243 	    (sco->state == BT_OPEN || sco->state == BT_CLOSED)) {
1244 		set_bit(HCI_CONN_POWER_SAVE, &acl->flags);
1245 		hci_conn_enter_active_mode(acl, BT_POWER_FORCE_ACTIVE_ON);
1246 
1247 		if (test_bit(HCI_CONN_MODE_CHANGE_PEND, &acl->flags)) {
1248 			/* defer SCO setup until mode change completed */
1249 			set_bit(HCI_CONN_SCO_SETUP_PEND, &acl->flags);
1250 			return sco;
1251 		}
1252 
1253 		hci_sco_setup(acl, 0x00);
1254 	}
1255 
1256 	return sco;
1257 }
1258 
1259 /* Check link security requirement */
1260 int hci_conn_check_link_mode(struct hci_conn *conn)
1261 {
1262 	BT_DBG("hcon %p", conn);
1263 
1264 	/* In Secure Connections Only mode, it is required that Secure
1265 	 * Connections is used and the link is encrypted with AES-CCM
1266 	 * using a P-256 authenticated combination key.
1267 	 */
1268 	if (hci_dev_test_flag(conn->hdev, HCI_SC_ONLY)) {
1269 		if (!hci_conn_sc_enabled(conn) ||
1270 		    !test_bit(HCI_CONN_AES_CCM, &conn->flags) ||
1271 		    conn->key_type != HCI_LK_AUTH_COMBINATION_P256)
1272 			return 0;
1273 	}
1274 
1275 	if (hci_conn_ssp_enabled(conn) &&
1276 	    !test_bit(HCI_CONN_ENCRYPT, &conn->flags))
1277 		return 0;
1278 
1279 	return 1;
1280 }
1281 
1282 /* Authenticate remote device */
1283 static int hci_conn_auth(struct hci_conn *conn, __u8 sec_level, __u8 auth_type)
1284 {
1285 	BT_DBG("hcon %p", conn);
1286 
1287 	if (conn->pending_sec_level > sec_level)
1288 		sec_level = conn->pending_sec_level;
1289 
1290 	if (sec_level > conn->sec_level)
1291 		conn->pending_sec_level = sec_level;
1292 	else if (test_bit(HCI_CONN_AUTH, &conn->flags))
1293 		return 1;
1294 
1295 	/* Make sure we preserve an existing MITM requirement*/
1296 	auth_type |= (conn->auth_type & 0x01);
1297 
1298 	conn->auth_type = auth_type;
1299 
1300 	if (!test_and_set_bit(HCI_CONN_AUTH_PEND, &conn->flags)) {
1301 		struct hci_cp_auth_requested cp;
1302 
1303 		cp.handle = cpu_to_le16(conn->handle);
1304 		hci_send_cmd(conn->hdev, HCI_OP_AUTH_REQUESTED,
1305 			     sizeof(cp), &cp);
1306 
1307 		/* If we're already encrypted set the REAUTH_PEND flag,
1308 		 * otherwise set the ENCRYPT_PEND.
1309 		 */
1310 		if (test_bit(HCI_CONN_ENCRYPT, &conn->flags))
1311 			set_bit(HCI_CONN_REAUTH_PEND, &conn->flags);
1312 		else
1313 			set_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags);
1314 	}
1315 
1316 	return 0;
1317 }
1318 
1319 /* Encrypt the the link */
1320 static void hci_conn_encrypt(struct hci_conn *conn)
1321 {
1322 	BT_DBG("hcon %p", conn);
1323 
1324 	if (!test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags)) {
1325 		struct hci_cp_set_conn_encrypt cp;
1326 		cp.handle  = cpu_to_le16(conn->handle);
1327 		cp.encrypt = 0x01;
1328 		hci_send_cmd(conn->hdev, HCI_OP_SET_CONN_ENCRYPT, sizeof(cp),
1329 			     &cp);
1330 	}
1331 }
1332 
1333 /* Enable security */
1334 int hci_conn_security(struct hci_conn *conn, __u8 sec_level, __u8 auth_type,
1335 		      bool initiator)
1336 {
1337 	BT_DBG("hcon %p", conn);
1338 
1339 	if (conn->type == LE_LINK)
1340 		return smp_conn_security(conn, sec_level);
1341 
1342 	/* For sdp we don't need the link key. */
1343 	if (sec_level == BT_SECURITY_SDP)
1344 		return 1;
1345 
1346 	/* For non 2.1 devices and low security level we don't need the link
1347 	   key. */
1348 	if (sec_level == BT_SECURITY_LOW && !hci_conn_ssp_enabled(conn))
1349 		return 1;
1350 
1351 	/* For other security levels we need the link key. */
1352 	if (!test_bit(HCI_CONN_AUTH, &conn->flags))
1353 		goto auth;
1354 
1355 	/* An authenticated FIPS approved combination key has sufficient
1356 	 * security for security level 4. */
1357 	if (conn->key_type == HCI_LK_AUTH_COMBINATION_P256 &&
1358 	    sec_level == BT_SECURITY_FIPS)
1359 		goto encrypt;
1360 
1361 	/* An authenticated combination key has sufficient security for
1362 	   security level 3. */
1363 	if ((conn->key_type == HCI_LK_AUTH_COMBINATION_P192 ||
1364 	     conn->key_type == HCI_LK_AUTH_COMBINATION_P256) &&
1365 	    sec_level == BT_SECURITY_HIGH)
1366 		goto encrypt;
1367 
1368 	/* An unauthenticated combination key has sufficient security for
1369 	   security level 1 and 2. */
1370 	if ((conn->key_type == HCI_LK_UNAUTH_COMBINATION_P192 ||
1371 	     conn->key_type == HCI_LK_UNAUTH_COMBINATION_P256) &&
1372 	    (sec_level == BT_SECURITY_MEDIUM || sec_level == BT_SECURITY_LOW))
1373 		goto encrypt;
1374 
1375 	/* A combination key has always sufficient security for the security
1376 	   levels 1 or 2. High security level requires the combination key
1377 	   is generated using maximum PIN code length (16).
1378 	   For pre 2.1 units. */
1379 	if (conn->key_type == HCI_LK_COMBINATION &&
1380 	    (sec_level == BT_SECURITY_MEDIUM || sec_level == BT_SECURITY_LOW ||
1381 	     conn->pin_length == 16))
1382 		goto encrypt;
1383 
1384 auth:
1385 	if (test_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags))
1386 		return 0;
1387 
1388 	if (initiator)
1389 		set_bit(HCI_CONN_AUTH_INITIATOR, &conn->flags);
1390 
1391 	if (!hci_conn_auth(conn, sec_level, auth_type))
1392 		return 0;
1393 
1394 encrypt:
1395 	if (test_bit(HCI_CONN_ENCRYPT, &conn->flags)) {
1396 		/* Ensure that the encryption key size has been read,
1397 		 * otherwise stall the upper layer responses.
1398 		 */
1399 		if (!conn->enc_key_size)
1400 			return 0;
1401 
1402 		/* Nothing else needed, all requirements are met */
1403 		return 1;
1404 	}
1405 
1406 	hci_conn_encrypt(conn);
1407 	return 0;
1408 }
1409 EXPORT_SYMBOL(hci_conn_security);
1410 
1411 /* Check secure link requirement */
1412 int hci_conn_check_secure(struct hci_conn *conn, __u8 sec_level)
1413 {
1414 	BT_DBG("hcon %p", conn);
1415 
1416 	/* Accept if non-secure or higher security level is required */
1417 	if (sec_level != BT_SECURITY_HIGH && sec_level != BT_SECURITY_FIPS)
1418 		return 1;
1419 
1420 	/* Accept if secure or higher security level is already present */
1421 	if (conn->sec_level == BT_SECURITY_HIGH ||
1422 	    conn->sec_level == BT_SECURITY_FIPS)
1423 		return 1;
1424 
1425 	/* Reject not secure link */
1426 	return 0;
1427 }
1428 EXPORT_SYMBOL(hci_conn_check_secure);
1429 
1430 /* Switch role */
1431 int hci_conn_switch_role(struct hci_conn *conn, __u8 role)
1432 {
1433 	BT_DBG("hcon %p", conn);
1434 
1435 	if (role == conn->role)
1436 		return 1;
1437 
1438 	if (!test_and_set_bit(HCI_CONN_RSWITCH_PEND, &conn->flags)) {
1439 		struct hci_cp_switch_role cp;
1440 		bacpy(&cp.bdaddr, &conn->dst);
1441 		cp.role = role;
1442 		hci_send_cmd(conn->hdev, HCI_OP_SWITCH_ROLE, sizeof(cp), &cp);
1443 	}
1444 
1445 	return 0;
1446 }
1447 EXPORT_SYMBOL(hci_conn_switch_role);
1448 
1449 /* Enter active mode */
1450 void hci_conn_enter_active_mode(struct hci_conn *conn, __u8 force_active)
1451 {
1452 	struct hci_dev *hdev = conn->hdev;
1453 
1454 	BT_DBG("hcon %p mode %d", conn, conn->mode);
1455 
1456 	if (conn->mode != HCI_CM_SNIFF)
1457 		goto timer;
1458 
1459 	if (!test_bit(HCI_CONN_POWER_SAVE, &conn->flags) && !force_active)
1460 		goto timer;
1461 
1462 	if (!test_and_set_bit(HCI_CONN_MODE_CHANGE_PEND, &conn->flags)) {
1463 		struct hci_cp_exit_sniff_mode cp;
1464 		cp.handle = cpu_to_le16(conn->handle);
1465 		hci_send_cmd(hdev, HCI_OP_EXIT_SNIFF_MODE, sizeof(cp), &cp);
1466 	}
1467 
1468 timer:
1469 	if (hdev->idle_timeout > 0)
1470 		queue_delayed_work(hdev->workqueue, &conn->idle_work,
1471 				   msecs_to_jiffies(hdev->idle_timeout));
1472 }
1473 
1474 /* Drop all connection on the device */
1475 void hci_conn_hash_flush(struct hci_dev *hdev)
1476 {
1477 	struct hci_conn_hash *h = &hdev->conn_hash;
1478 	struct hci_conn *c, *n;
1479 
1480 	BT_DBG("hdev %s", hdev->name);
1481 
1482 	list_for_each_entry_safe(c, n, &h->list, list) {
1483 		c->state = BT_CLOSED;
1484 
1485 		hci_disconn_cfm(c, HCI_ERROR_LOCAL_HOST_TERM);
1486 		hci_conn_del(c);
1487 	}
1488 }
1489 
1490 /* Check pending connect attempts */
1491 void hci_conn_check_pending(struct hci_dev *hdev)
1492 {
1493 	struct hci_conn *conn;
1494 
1495 	BT_DBG("hdev %s", hdev->name);
1496 
1497 	hci_dev_lock(hdev);
1498 
1499 	conn = hci_conn_hash_lookup_state(hdev, ACL_LINK, BT_CONNECT2);
1500 	if (conn)
1501 		hci_acl_create_connection(conn);
1502 
1503 	hci_dev_unlock(hdev);
1504 }
1505 
1506 static u32 get_link_mode(struct hci_conn *conn)
1507 {
1508 	u32 link_mode = 0;
1509 
1510 	if (conn->role == HCI_ROLE_MASTER)
1511 		link_mode |= HCI_LM_MASTER;
1512 
1513 	if (test_bit(HCI_CONN_ENCRYPT, &conn->flags))
1514 		link_mode |= HCI_LM_ENCRYPT;
1515 
1516 	if (test_bit(HCI_CONN_AUTH, &conn->flags))
1517 		link_mode |= HCI_LM_AUTH;
1518 
1519 	if (test_bit(HCI_CONN_SECURE, &conn->flags))
1520 		link_mode |= HCI_LM_SECURE;
1521 
1522 	if (test_bit(HCI_CONN_FIPS, &conn->flags))
1523 		link_mode |= HCI_LM_FIPS;
1524 
1525 	return link_mode;
1526 }
1527 
1528 int hci_get_conn_list(void __user *arg)
1529 {
1530 	struct hci_conn *c;
1531 	struct hci_conn_list_req req, *cl;
1532 	struct hci_conn_info *ci;
1533 	struct hci_dev *hdev;
1534 	int n = 0, size, err;
1535 
1536 	if (copy_from_user(&req, arg, sizeof(req)))
1537 		return -EFAULT;
1538 
1539 	if (!req.conn_num || req.conn_num > (PAGE_SIZE * 2) / sizeof(*ci))
1540 		return -EINVAL;
1541 
1542 	size = sizeof(req) + req.conn_num * sizeof(*ci);
1543 
1544 	cl = kmalloc(size, GFP_KERNEL);
1545 	if (!cl)
1546 		return -ENOMEM;
1547 
1548 	hdev = hci_dev_get(req.dev_id);
1549 	if (!hdev) {
1550 		kfree(cl);
1551 		return -ENODEV;
1552 	}
1553 
1554 	ci = cl->conn_info;
1555 
1556 	hci_dev_lock(hdev);
1557 	list_for_each_entry(c, &hdev->conn_hash.list, list) {
1558 		bacpy(&(ci + n)->bdaddr, &c->dst);
1559 		(ci + n)->handle = c->handle;
1560 		(ci + n)->type  = c->type;
1561 		(ci + n)->out   = c->out;
1562 		(ci + n)->state = c->state;
1563 		(ci + n)->link_mode = get_link_mode(c);
1564 		if (++n >= req.conn_num)
1565 			break;
1566 	}
1567 	hci_dev_unlock(hdev);
1568 
1569 	cl->dev_id = hdev->id;
1570 	cl->conn_num = n;
1571 	size = sizeof(req) + n * sizeof(*ci);
1572 
1573 	hci_dev_put(hdev);
1574 
1575 	err = copy_to_user(arg, cl, size);
1576 	kfree(cl);
1577 
1578 	return err ? -EFAULT : 0;
1579 }
1580 
1581 int hci_get_conn_info(struct hci_dev *hdev, void __user *arg)
1582 {
1583 	struct hci_conn_info_req req;
1584 	struct hci_conn_info ci;
1585 	struct hci_conn *conn;
1586 	char __user *ptr = arg + sizeof(req);
1587 
1588 	if (copy_from_user(&req, arg, sizeof(req)))
1589 		return -EFAULT;
1590 
1591 	hci_dev_lock(hdev);
1592 	conn = hci_conn_hash_lookup_ba(hdev, req.type, &req.bdaddr);
1593 	if (conn) {
1594 		bacpy(&ci.bdaddr, &conn->dst);
1595 		ci.handle = conn->handle;
1596 		ci.type  = conn->type;
1597 		ci.out   = conn->out;
1598 		ci.state = conn->state;
1599 		ci.link_mode = get_link_mode(conn);
1600 	}
1601 	hci_dev_unlock(hdev);
1602 
1603 	if (!conn)
1604 		return -ENOENT;
1605 
1606 	return copy_to_user(ptr, &ci, sizeof(ci)) ? -EFAULT : 0;
1607 }
1608 
1609 int hci_get_auth_info(struct hci_dev *hdev, void __user *arg)
1610 {
1611 	struct hci_auth_info_req req;
1612 	struct hci_conn *conn;
1613 
1614 	if (copy_from_user(&req, arg, sizeof(req)))
1615 		return -EFAULT;
1616 
1617 	hci_dev_lock(hdev);
1618 	conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, &req.bdaddr);
1619 	if (conn)
1620 		req.type = conn->auth_type;
1621 	hci_dev_unlock(hdev);
1622 
1623 	if (!conn)
1624 		return -ENOENT;
1625 
1626 	return copy_to_user(arg, &req, sizeof(req)) ? -EFAULT : 0;
1627 }
1628 
1629 struct hci_chan *hci_chan_create(struct hci_conn *conn)
1630 {
1631 	struct hci_dev *hdev = conn->hdev;
1632 	struct hci_chan *chan;
1633 
1634 	BT_DBG("%s hcon %p", hdev->name, conn);
1635 
1636 	if (test_bit(HCI_CONN_DROP, &conn->flags)) {
1637 		BT_DBG("Refusing to create new hci_chan");
1638 		return NULL;
1639 	}
1640 
1641 	chan = kzalloc(sizeof(*chan), GFP_KERNEL);
1642 	if (!chan)
1643 		return NULL;
1644 
1645 	chan->conn = hci_conn_get(conn);
1646 	skb_queue_head_init(&chan->data_q);
1647 	chan->state = BT_CONNECTED;
1648 
1649 	list_add_rcu(&chan->list, &conn->chan_list);
1650 
1651 	return chan;
1652 }
1653 
1654 void hci_chan_del(struct hci_chan *chan)
1655 {
1656 	struct hci_conn *conn = chan->conn;
1657 	struct hci_dev *hdev = conn->hdev;
1658 
1659 	BT_DBG("%s hcon %p chan %p", hdev->name, conn, chan);
1660 
1661 	list_del_rcu(&chan->list);
1662 
1663 	synchronize_rcu();
1664 
1665 	/* Prevent new hci_chan's to be created for this hci_conn */
1666 	set_bit(HCI_CONN_DROP, &conn->flags);
1667 
1668 	hci_conn_put(conn);
1669 
1670 	skb_queue_purge(&chan->data_q);
1671 	kfree(chan);
1672 }
1673 
1674 void hci_chan_list_flush(struct hci_conn *conn)
1675 {
1676 	struct hci_chan *chan, *n;
1677 
1678 	BT_DBG("hcon %p", conn);
1679 
1680 	list_for_each_entry_safe(chan, n, &conn->chan_list, list)
1681 		hci_chan_del(chan);
1682 }
1683 
1684 static struct hci_chan *__hci_chan_lookup_handle(struct hci_conn *hcon,
1685 						 __u16 handle)
1686 {
1687 	struct hci_chan *hchan;
1688 
1689 	list_for_each_entry(hchan, &hcon->chan_list, list) {
1690 		if (hchan->handle == handle)
1691 			return hchan;
1692 	}
1693 
1694 	return NULL;
1695 }
1696 
1697 struct hci_chan *hci_chan_lookup_handle(struct hci_dev *hdev, __u16 handle)
1698 {
1699 	struct hci_conn_hash *h = &hdev->conn_hash;
1700 	struct hci_conn *hcon;
1701 	struct hci_chan *hchan = NULL;
1702 
1703 	rcu_read_lock();
1704 
1705 	list_for_each_entry_rcu(hcon, &h->list, list) {
1706 		hchan = __hci_chan_lookup_handle(hcon, handle);
1707 		if (hchan)
1708 			break;
1709 	}
1710 
1711 	rcu_read_unlock();
1712 
1713 	return hchan;
1714 }
1715