xref: /linux/net/bluetooth/hci_conn.c (revision 2c63221cd9e5c0dad0424029aeb1c40faada8330)
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 	/* Set Default Authenticated payload timeout to 30s */
524 	conn->auth_payload_timeout = DEFAULT_AUTH_PAYLOAD_TIMEOUT;
525 
526 	if (conn->role == HCI_ROLE_MASTER)
527 		conn->out = true;
528 
529 	switch (type) {
530 	case ACL_LINK:
531 		conn->pkt_type = hdev->pkt_type & ACL_PTYPE_MASK;
532 		break;
533 	case LE_LINK:
534 		/* conn->src should reflect the local identity address */
535 		hci_copy_identity_address(hdev, &conn->src, &conn->src_type);
536 		break;
537 	case SCO_LINK:
538 		if (lmp_esco_capable(hdev))
539 			conn->pkt_type = (hdev->esco_type & SCO_ESCO_MASK) |
540 					(hdev->esco_type & EDR_ESCO_MASK);
541 		else
542 			conn->pkt_type = hdev->pkt_type & SCO_PTYPE_MASK;
543 		break;
544 	case ESCO_LINK:
545 		conn->pkt_type = hdev->esco_type & ~EDR_ESCO_MASK;
546 		break;
547 	}
548 
549 	skb_queue_head_init(&conn->data_q);
550 
551 	INIT_LIST_HEAD(&conn->chan_list);
552 
553 	INIT_DELAYED_WORK(&conn->disc_work, hci_conn_timeout);
554 	INIT_DELAYED_WORK(&conn->auto_accept_work, hci_conn_auto_accept);
555 	INIT_DELAYED_WORK(&conn->idle_work, hci_conn_idle);
556 	INIT_DELAYED_WORK(&conn->le_conn_timeout, le_conn_timeout);
557 	INIT_WORK(&conn->le_scan_cleanup, le_scan_cleanup);
558 
559 	atomic_set(&conn->refcnt, 0);
560 
561 	hci_dev_hold(hdev);
562 
563 	hci_conn_hash_add(hdev, conn);
564 	if (hdev->notify)
565 		hdev->notify(hdev, HCI_NOTIFY_CONN_ADD);
566 
567 	hci_conn_init_sysfs(conn);
568 
569 	return conn;
570 }
571 
572 int hci_conn_del(struct hci_conn *conn)
573 {
574 	struct hci_dev *hdev = conn->hdev;
575 
576 	BT_DBG("%s hcon %p handle %d", hdev->name, conn, conn->handle);
577 
578 	cancel_delayed_work_sync(&conn->disc_work);
579 	cancel_delayed_work_sync(&conn->auto_accept_work);
580 	cancel_delayed_work_sync(&conn->idle_work);
581 
582 	if (conn->type == ACL_LINK) {
583 		struct hci_conn *sco = conn->link;
584 		if (sco)
585 			sco->link = NULL;
586 
587 		/* Unacked frames */
588 		hdev->acl_cnt += conn->sent;
589 	} else if (conn->type == LE_LINK) {
590 		cancel_delayed_work(&conn->le_conn_timeout);
591 
592 		if (hdev->le_pkts)
593 			hdev->le_cnt += conn->sent;
594 		else
595 			hdev->acl_cnt += conn->sent;
596 	} else {
597 		struct hci_conn *acl = conn->link;
598 		if (acl) {
599 			acl->link = NULL;
600 			hci_conn_drop(acl);
601 		}
602 	}
603 
604 	if (conn->amp_mgr)
605 		amp_mgr_put(conn->amp_mgr);
606 
607 	skb_queue_purge(&conn->data_q);
608 
609 	/* Remove the connection from the list and cleanup its remaining
610 	 * state. This is a separate function since for some cases like
611 	 * BT_CONNECT_SCAN we *only* want the cleanup part without the
612 	 * rest of hci_conn_del.
613 	 */
614 	hci_conn_cleanup(conn);
615 
616 	return 0;
617 }
618 
619 struct hci_dev *hci_get_route(bdaddr_t *dst, bdaddr_t *src, uint8_t src_type)
620 {
621 	int use_src = bacmp(src, BDADDR_ANY);
622 	struct hci_dev *hdev = NULL, *d;
623 
624 	BT_DBG("%pMR -> %pMR", src, dst);
625 
626 	read_lock(&hci_dev_list_lock);
627 
628 	list_for_each_entry(d, &hci_dev_list, list) {
629 		if (!test_bit(HCI_UP, &d->flags) ||
630 		    hci_dev_test_flag(d, HCI_USER_CHANNEL) ||
631 		    d->dev_type != HCI_PRIMARY)
632 			continue;
633 
634 		/* Simple routing:
635 		 *   No source address - find interface with bdaddr != dst
636 		 *   Source address    - find interface with bdaddr == src
637 		 */
638 
639 		if (use_src) {
640 			bdaddr_t id_addr;
641 			u8 id_addr_type;
642 
643 			if (src_type == BDADDR_BREDR) {
644 				if (!lmp_bredr_capable(d))
645 					continue;
646 				bacpy(&id_addr, &d->bdaddr);
647 				id_addr_type = BDADDR_BREDR;
648 			} else {
649 				if (!lmp_le_capable(d))
650 					continue;
651 
652 				hci_copy_identity_address(d, &id_addr,
653 							  &id_addr_type);
654 
655 				/* Convert from HCI to three-value type */
656 				if (id_addr_type == ADDR_LE_DEV_PUBLIC)
657 					id_addr_type = BDADDR_LE_PUBLIC;
658 				else
659 					id_addr_type = BDADDR_LE_RANDOM;
660 			}
661 
662 			if (!bacmp(&id_addr, src) && id_addr_type == src_type) {
663 				hdev = d; break;
664 			}
665 		} else {
666 			if (bacmp(&d->bdaddr, dst)) {
667 				hdev = d; break;
668 			}
669 		}
670 	}
671 
672 	if (hdev)
673 		hdev = hci_dev_hold(hdev);
674 
675 	read_unlock(&hci_dev_list_lock);
676 	return hdev;
677 }
678 EXPORT_SYMBOL(hci_get_route);
679 
680 /* This function requires the caller holds hdev->lock */
681 void hci_le_conn_failed(struct hci_conn *conn, u8 status)
682 {
683 	struct hci_dev *hdev = conn->hdev;
684 	struct hci_conn_params *params;
685 
686 	params = hci_pend_le_action_lookup(&hdev->pend_le_conns, &conn->dst,
687 					   conn->dst_type);
688 	if (params && params->conn) {
689 		hci_conn_drop(params->conn);
690 		hci_conn_put(params->conn);
691 		params->conn = NULL;
692 	}
693 
694 	conn->state = BT_CLOSED;
695 
696 	/* If the status indicates successful cancellation of
697 	 * the attempt (i.e. Unkown Connection Id) there's no point of
698 	 * notifying failure since we'll go back to keep trying to
699 	 * connect. The only exception is explicit connect requests
700 	 * where a timeout + cancel does indicate an actual failure.
701 	 */
702 	if (status != HCI_ERROR_UNKNOWN_CONN_ID ||
703 	    (params && params->explicit_connect))
704 		mgmt_connect_failed(hdev, &conn->dst, conn->type,
705 				    conn->dst_type, status);
706 
707 	hci_connect_cfm(conn, status);
708 
709 	hci_conn_del(conn);
710 
711 	/* Since we may have temporarily stopped the background scanning in
712 	 * favor of connection establishment, we should restart it.
713 	 */
714 	hci_update_background_scan(hdev);
715 
716 	/* Re-enable advertising in case this was a failed connection
717 	 * attempt as a peripheral.
718 	 */
719 	hci_req_reenable_advertising(hdev);
720 }
721 
722 static void create_le_conn_complete(struct hci_dev *hdev, u8 status, u16 opcode)
723 {
724 	struct hci_conn *conn;
725 
726 	hci_dev_lock(hdev);
727 
728 	conn = hci_lookup_le_connect(hdev);
729 
730 	if (!status) {
731 		hci_connect_le_scan_cleanup(conn);
732 		goto done;
733 	}
734 
735 	bt_dev_err(hdev, "request failed to create LE connection: "
736 		   "status 0x%2.2x", status);
737 
738 	if (!conn)
739 		goto done;
740 
741 	hci_le_conn_failed(conn, status);
742 
743 done:
744 	hci_dev_unlock(hdev);
745 }
746 
747 static bool conn_use_rpa(struct hci_conn *conn)
748 {
749 	struct hci_dev *hdev = conn->hdev;
750 
751 	return hci_dev_test_flag(hdev, HCI_PRIVACY);
752 }
753 
754 static void set_ext_conn_params(struct hci_conn *conn,
755 				struct hci_cp_le_ext_conn_param *p)
756 {
757 	struct hci_dev *hdev = conn->hdev;
758 
759 	memset(p, 0, sizeof(*p));
760 
761 	/* Set window to be the same value as the interval to
762 	 * enable continuous scanning.
763 	 */
764 	p->scan_interval = cpu_to_le16(hdev->le_scan_interval);
765 	p->scan_window = p->scan_interval;
766 	p->conn_interval_min = cpu_to_le16(conn->le_conn_min_interval);
767 	p->conn_interval_max = cpu_to_le16(conn->le_conn_max_interval);
768 	p->conn_latency = cpu_to_le16(conn->le_conn_latency);
769 	p->supervision_timeout = cpu_to_le16(conn->le_supv_timeout);
770 	p->min_ce_len = cpu_to_le16(0x0000);
771 	p->max_ce_len = cpu_to_le16(0x0000);
772 }
773 
774 static void hci_req_add_le_create_conn(struct hci_request *req,
775 				       struct hci_conn *conn,
776 				       bdaddr_t *direct_rpa)
777 {
778 	struct hci_dev *hdev = conn->hdev;
779 	u8 own_addr_type;
780 
781 	/* If direct address was provided we use it instead of current
782 	 * address.
783 	 */
784 	if (direct_rpa) {
785 		if (bacmp(&req->hdev->random_addr, direct_rpa))
786 			hci_req_add(req, HCI_OP_LE_SET_RANDOM_ADDR, 6,
787 								direct_rpa);
788 
789 		/* direct address is always RPA */
790 		own_addr_type = ADDR_LE_DEV_RANDOM;
791 	} else {
792 		/* Update random address, but set require_privacy to false so
793 		 * that we never connect with an non-resolvable address.
794 		 */
795 		if (hci_update_random_address(req, false, conn_use_rpa(conn),
796 					      &own_addr_type))
797 			return;
798 	}
799 
800 	if (use_ext_conn(hdev)) {
801 		struct hci_cp_le_ext_create_conn *cp;
802 		struct hci_cp_le_ext_conn_param *p;
803 		u8 data[sizeof(*cp) + sizeof(*p) * 3];
804 		u32 plen;
805 
806 		cp = (void *) data;
807 		p = (void *) cp->data;
808 
809 		memset(cp, 0, sizeof(*cp));
810 
811 		bacpy(&cp->peer_addr, &conn->dst);
812 		cp->peer_addr_type = conn->dst_type;
813 		cp->own_addr_type = own_addr_type;
814 
815 		plen = sizeof(*cp);
816 
817 		if (scan_1m(hdev)) {
818 			cp->phys |= LE_SCAN_PHY_1M;
819 			set_ext_conn_params(conn, p);
820 
821 			p++;
822 			plen += sizeof(*p);
823 		}
824 
825 		if (scan_2m(hdev)) {
826 			cp->phys |= LE_SCAN_PHY_2M;
827 			set_ext_conn_params(conn, p);
828 
829 			p++;
830 			plen += sizeof(*p);
831 		}
832 
833 		if (scan_coded(hdev)) {
834 			cp->phys |= LE_SCAN_PHY_CODED;
835 			set_ext_conn_params(conn, p);
836 
837 			plen += sizeof(*p);
838 		}
839 
840 		hci_req_add(req, HCI_OP_LE_EXT_CREATE_CONN, plen, data);
841 
842 	} else {
843 		struct hci_cp_le_create_conn cp;
844 
845 		memset(&cp, 0, sizeof(cp));
846 
847 		/* Set window to be the same value as the interval to enable
848 		 * continuous scanning.
849 		 */
850 		cp.scan_interval = cpu_to_le16(hdev->le_scan_interval);
851 		cp.scan_window = cp.scan_interval;
852 
853 		bacpy(&cp.peer_addr, &conn->dst);
854 		cp.peer_addr_type = conn->dst_type;
855 		cp.own_address_type = own_addr_type;
856 		cp.conn_interval_min = cpu_to_le16(conn->le_conn_min_interval);
857 		cp.conn_interval_max = cpu_to_le16(conn->le_conn_max_interval);
858 		cp.conn_latency = cpu_to_le16(conn->le_conn_latency);
859 		cp.supervision_timeout = cpu_to_le16(conn->le_supv_timeout);
860 		cp.min_ce_len = cpu_to_le16(0x0000);
861 		cp.max_ce_len = cpu_to_le16(0x0000);
862 
863 		hci_req_add(req, HCI_OP_LE_CREATE_CONN, sizeof(cp), &cp);
864 	}
865 
866 	conn->state = BT_CONNECT;
867 	clear_bit(HCI_CONN_SCANNING, &conn->flags);
868 }
869 
870 static void hci_req_directed_advertising(struct hci_request *req,
871 					 struct hci_conn *conn)
872 {
873 	struct hci_dev *hdev = req->hdev;
874 	u8 own_addr_type;
875 	u8 enable;
876 
877 	if (ext_adv_capable(hdev)) {
878 		struct hci_cp_le_set_ext_adv_params cp;
879 		bdaddr_t random_addr;
880 
881 		/* Set require_privacy to false so that the remote device has a
882 		 * chance of identifying us.
883 		 */
884 		if (hci_get_random_address(hdev, false, conn_use_rpa(conn), NULL,
885 					   &own_addr_type, &random_addr) < 0)
886 			return;
887 
888 		memset(&cp, 0, sizeof(cp));
889 
890 		cp.evt_properties = cpu_to_le16(LE_LEGACY_ADV_DIRECT_IND);
891 		cp.own_addr_type = own_addr_type;
892 		cp.channel_map = hdev->le_adv_channel_map;
893 		cp.tx_power = HCI_TX_POWER_INVALID;
894 		cp.primary_phy = HCI_ADV_PHY_1M;
895 		cp.secondary_phy = HCI_ADV_PHY_1M;
896 		cp.handle = 0; /* Use instance 0 for directed adv */
897 		cp.own_addr_type = own_addr_type;
898 		cp.peer_addr_type = conn->dst_type;
899 		bacpy(&cp.peer_addr, &conn->dst);
900 
901 		hci_req_add(req, HCI_OP_LE_SET_EXT_ADV_PARAMS, sizeof(cp), &cp);
902 
903 		if (own_addr_type == ADDR_LE_DEV_RANDOM &&
904 		    bacmp(&random_addr, BDADDR_ANY) &&
905 		    bacmp(&random_addr, &hdev->random_addr)) {
906 			struct hci_cp_le_set_adv_set_rand_addr cp;
907 
908 			memset(&cp, 0, sizeof(cp));
909 
910 			cp.handle = 0;
911 			bacpy(&cp.bdaddr, &random_addr);
912 
913 			hci_req_add(req,
914 				    HCI_OP_LE_SET_ADV_SET_RAND_ADDR,
915 				    sizeof(cp), &cp);
916 		}
917 
918 		__hci_req_enable_ext_advertising(req, 0x00);
919 	} else {
920 		struct hci_cp_le_set_adv_param cp;
921 
922 		/* Clear the HCI_LE_ADV bit temporarily so that the
923 		 * hci_update_random_address knows that it's safe to go ahead
924 		 * and write a new random address. The flag will be set back on
925 		 * as soon as the SET_ADV_ENABLE HCI command completes.
926 		 */
927 		hci_dev_clear_flag(hdev, HCI_LE_ADV);
928 
929 		/* Set require_privacy to false so that the remote device has a
930 		 * chance of identifying us.
931 		 */
932 		if (hci_update_random_address(req, false, conn_use_rpa(conn),
933 					      &own_addr_type) < 0)
934 			return;
935 
936 		memset(&cp, 0, sizeof(cp));
937 
938 		/* Some controllers might reject command if intervals are not
939 		 * within range for undirected advertising.
940 		 * BCM20702A0 is known to be affected by this.
941 		 */
942 		cp.min_interval = cpu_to_le16(0x0020);
943 		cp.max_interval = cpu_to_le16(0x0020);
944 
945 		cp.type = LE_ADV_DIRECT_IND;
946 		cp.own_address_type = own_addr_type;
947 		cp.direct_addr_type = conn->dst_type;
948 		bacpy(&cp.direct_addr, &conn->dst);
949 		cp.channel_map = hdev->le_adv_channel_map;
950 
951 		hci_req_add(req, HCI_OP_LE_SET_ADV_PARAM, sizeof(cp), &cp);
952 
953 		enable = 0x01;
954 		hci_req_add(req, HCI_OP_LE_SET_ADV_ENABLE, sizeof(enable),
955 			    &enable);
956 	}
957 
958 	conn->state = BT_CONNECT;
959 }
960 
961 struct hci_conn *hci_connect_le(struct hci_dev *hdev, bdaddr_t *dst,
962 				u8 dst_type, u8 sec_level, u16 conn_timeout,
963 				u8 role, bdaddr_t *direct_rpa)
964 {
965 	struct hci_conn_params *params;
966 	struct hci_conn *conn;
967 	struct smp_irk *irk;
968 	struct hci_request req;
969 	int err;
970 
971 	/* Let's make sure that le is enabled.*/
972 	if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED)) {
973 		if (lmp_le_capable(hdev))
974 			return ERR_PTR(-ECONNREFUSED);
975 
976 		return ERR_PTR(-EOPNOTSUPP);
977 	}
978 
979 	/* Since the controller supports only one LE connection attempt at a
980 	 * time, we return -EBUSY if there is any connection attempt running.
981 	 */
982 	if (hci_lookup_le_connect(hdev))
983 		return ERR_PTR(-EBUSY);
984 
985 	/* If there's already a connection object but it's not in
986 	 * scanning state it means it must already be established, in
987 	 * which case we can't do anything else except report a failure
988 	 * to connect.
989 	 */
990 	conn = hci_conn_hash_lookup_le(hdev, dst, dst_type);
991 	if (conn && !test_bit(HCI_CONN_SCANNING, &conn->flags)) {
992 		return ERR_PTR(-EBUSY);
993 	}
994 
995 	/* When given an identity address with existing identity
996 	 * resolving key, the connection needs to be established
997 	 * to a resolvable random address.
998 	 *
999 	 * Storing the resolvable random address is required here
1000 	 * to handle connection failures. The address will later
1001 	 * be resolved back into the original identity address
1002 	 * from the connect request.
1003 	 */
1004 	irk = hci_find_irk_by_addr(hdev, dst, dst_type);
1005 	if (irk && bacmp(&irk->rpa, BDADDR_ANY)) {
1006 		dst = &irk->rpa;
1007 		dst_type = ADDR_LE_DEV_RANDOM;
1008 	}
1009 
1010 	if (conn) {
1011 		bacpy(&conn->dst, dst);
1012 	} else {
1013 		conn = hci_conn_add(hdev, LE_LINK, dst, role);
1014 		if (!conn)
1015 			return ERR_PTR(-ENOMEM);
1016 		hci_conn_hold(conn);
1017 		conn->pending_sec_level = sec_level;
1018 	}
1019 
1020 	conn->dst_type = dst_type;
1021 	conn->sec_level = BT_SECURITY_LOW;
1022 	conn->conn_timeout = conn_timeout;
1023 
1024 	hci_req_init(&req, hdev);
1025 
1026 	/* Disable advertising if we're active. For master role
1027 	 * connections most controllers will refuse to connect if
1028 	 * advertising is enabled, and for slave role connections we
1029 	 * anyway have to disable it in order to start directed
1030 	 * advertising.
1031 	 */
1032 	if (hci_dev_test_flag(hdev, HCI_LE_ADV)) {
1033 		u8 enable = 0x00;
1034 		hci_req_add(&req, HCI_OP_LE_SET_ADV_ENABLE, sizeof(enable),
1035 			    &enable);
1036 	}
1037 
1038 	/* If requested to connect as slave use directed advertising */
1039 	if (conn->role == HCI_ROLE_SLAVE) {
1040 		/* If we're active scanning most controllers are unable
1041 		 * to initiate advertising. Simply reject the attempt.
1042 		 */
1043 		if (hci_dev_test_flag(hdev, HCI_LE_SCAN) &&
1044 		    hdev->le_scan_type == LE_SCAN_ACTIVE) {
1045 			hci_req_purge(&req);
1046 			hci_conn_del(conn);
1047 			return ERR_PTR(-EBUSY);
1048 		}
1049 
1050 		hci_req_directed_advertising(&req, conn);
1051 		goto create_conn;
1052 	}
1053 
1054 	params = hci_conn_params_lookup(hdev, &conn->dst, conn->dst_type);
1055 	if (params) {
1056 		conn->le_conn_min_interval = params->conn_min_interval;
1057 		conn->le_conn_max_interval = params->conn_max_interval;
1058 		conn->le_conn_latency = params->conn_latency;
1059 		conn->le_supv_timeout = params->supervision_timeout;
1060 	} else {
1061 		conn->le_conn_min_interval = hdev->le_conn_min_interval;
1062 		conn->le_conn_max_interval = hdev->le_conn_max_interval;
1063 		conn->le_conn_latency = hdev->le_conn_latency;
1064 		conn->le_supv_timeout = hdev->le_supv_timeout;
1065 	}
1066 
1067 	/* If controller is scanning, we stop it since some controllers are
1068 	 * not able to scan and connect at the same time. Also set the
1069 	 * HCI_LE_SCAN_INTERRUPTED flag so that the command complete
1070 	 * handler for scan disabling knows to set the correct discovery
1071 	 * state.
1072 	 */
1073 	if (hci_dev_test_flag(hdev, HCI_LE_SCAN)) {
1074 		hci_req_add_le_scan_disable(&req);
1075 		hci_dev_set_flag(hdev, HCI_LE_SCAN_INTERRUPTED);
1076 	}
1077 
1078 	hci_req_add_le_create_conn(&req, conn, direct_rpa);
1079 
1080 create_conn:
1081 	err = hci_req_run(&req, create_le_conn_complete);
1082 	if (err) {
1083 		hci_conn_del(conn);
1084 		return ERR_PTR(err);
1085 	}
1086 
1087 	return conn;
1088 }
1089 
1090 static bool is_connected(struct hci_dev *hdev, bdaddr_t *addr, u8 type)
1091 {
1092 	struct hci_conn *conn;
1093 
1094 	conn = hci_conn_hash_lookup_le(hdev, addr, type);
1095 	if (!conn)
1096 		return false;
1097 
1098 	if (conn->state != BT_CONNECTED)
1099 		return false;
1100 
1101 	return true;
1102 }
1103 
1104 /* This function requires the caller holds hdev->lock */
1105 static int hci_explicit_conn_params_set(struct hci_dev *hdev,
1106 					bdaddr_t *addr, u8 addr_type)
1107 {
1108 	struct hci_conn_params *params;
1109 
1110 	if (is_connected(hdev, addr, addr_type))
1111 		return -EISCONN;
1112 
1113 	params = hci_conn_params_lookup(hdev, addr, addr_type);
1114 	if (!params) {
1115 		params = hci_conn_params_add(hdev, addr, addr_type);
1116 		if (!params)
1117 			return -ENOMEM;
1118 
1119 		/* If we created new params, mark them to be deleted in
1120 		 * hci_connect_le_scan_cleanup. It's different case than
1121 		 * existing disabled params, those will stay after cleanup.
1122 		 */
1123 		params->auto_connect = HCI_AUTO_CONN_EXPLICIT;
1124 	}
1125 
1126 	/* We're trying to connect, so make sure params are at pend_le_conns */
1127 	if (params->auto_connect == HCI_AUTO_CONN_DISABLED ||
1128 	    params->auto_connect == HCI_AUTO_CONN_REPORT ||
1129 	    params->auto_connect == HCI_AUTO_CONN_EXPLICIT) {
1130 		list_del_init(&params->action);
1131 		list_add(&params->action, &hdev->pend_le_conns);
1132 	}
1133 
1134 	params->explicit_connect = true;
1135 
1136 	BT_DBG("addr %pMR (type %u) auto_connect %u", addr, addr_type,
1137 	       params->auto_connect);
1138 
1139 	return 0;
1140 }
1141 
1142 /* This function requires the caller holds hdev->lock */
1143 struct hci_conn *hci_connect_le_scan(struct hci_dev *hdev, bdaddr_t *dst,
1144 				     u8 dst_type, u8 sec_level,
1145 				     u16 conn_timeout)
1146 {
1147 	struct hci_conn *conn;
1148 
1149 	/* Let's make sure that le is enabled.*/
1150 	if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED)) {
1151 		if (lmp_le_capable(hdev))
1152 			return ERR_PTR(-ECONNREFUSED);
1153 
1154 		return ERR_PTR(-EOPNOTSUPP);
1155 	}
1156 
1157 	/* Some devices send ATT messages as soon as the physical link is
1158 	 * established. To be able to handle these ATT messages, the user-
1159 	 * space first establishes the connection and then starts the pairing
1160 	 * process.
1161 	 *
1162 	 * So if a hci_conn object already exists for the following connection
1163 	 * attempt, we simply update pending_sec_level and auth_type fields
1164 	 * and return the object found.
1165 	 */
1166 	conn = hci_conn_hash_lookup_le(hdev, dst, dst_type);
1167 	if (conn) {
1168 		if (conn->pending_sec_level < sec_level)
1169 			conn->pending_sec_level = sec_level;
1170 		goto done;
1171 	}
1172 
1173 	BT_DBG("requesting refresh of dst_addr");
1174 
1175 	conn = hci_conn_add(hdev, LE_LINK, dst, HCI_ROLE_MASTER);
1176 	if (!conn)
1177 		return ERR_PTR(-ENOMEM);
1178 
1179 	if (hci_explicit_conn_params_set(hdev, dst, dst_type) < 0)
1180 		return ERR_PTR(-EBUSY);
1181 
1182 	conn->state = BT_CONNECT;
1183 	set_bit(HCI_CONN_SCANNING, &conn->flags);
1184 	conn->dst_type = dst_type;
1185 	conn->sec_level = BT_SECURITY_LOW;
1186 	conn->pending_sec_level = sec_level;
1187 	conn->conn_timeout = conn_timeout;
1188 
1189 	hci_update_background_scan(hdev);
1190 
1191 done:
1192 	hci_conn_hold(conn);
1193 	return conn;
1194 }
1195 
1196 struct hci_conn *hci_connect_acl(struct hci_dev *hdev, bdaddr_t *dst,
1197 				 u8 sec_level, u8 auth_type)
1198 {
1199 	struct hci_conn *acl;
1200 
1201 	if (!hci_dev_test_flag(hdev, HCI_BREDR_ENABLED)) {
1202 		if (lmp_bredr_capable(hdev))
1203 			return ERR_PTR(-ECONNREFUSED);
1204 
1205 		return ERR_PTR(-EOPNOTSUPP);
1206 	}
1207 
1208 	acl = hci_conn_hash_lookup_ba(hdev, ACL_LINK, dst);
1209 	if (!acl) {
1210 		acl = hci_conn_add(hdev, ACL_LINK, dst, HCI_ROLE_MASTER);
1211 		if (!acl)
1212 			return ERR_PTR(-ENOMEM);
1213 	}
1214 
1215 	hci_conn_hold(acl);
1216 
1217 	if (acl->state == BT_OPEN || acl->state == BT_CLOSED) {
1218 		acl->sec_level = BT_SECURITY_LOW;
1219 		acl->pending_sec_level = sec_level;
1220 		acl->auth_type = auth_type;
1221 		hci_acl_create_connection(acl);
1222 	}
1223 
1224 	return acl;
1225 }
1226 
1227 struct hci_conn *hci_connect_sco(struct hci_dev *hdev, int type, bdaddr_t *dst,
1228 				 __u16 setting)
1229 {
1230 	struct hci_conn *acl;
1231 	struct hci_conn *sco;
1232 
1233 	acl = hci_connect_acl(hdev, dst, BT_SECURITY_LOW, HCI_AT_NO_BONDING);
1234 	if (IS_ERR(acl))
1235 		return acl;
1236 
1237 	sco = hci_conn_hash_lookup_ba(hdev, type, dst);
1238 	if (!sco) {
1239 		sco = hci_conn_add(hdev, type, dst, HCI_ROLE_MASTER);
1240 		if (!sco) {
1241 			hci_conn_drop(acl);
1242 			return ERR_PTR(-ENOMEM);
1243 		}
1244 	}
1245 
1246 	acl->link = sco;
1247 	sco->link = acl;
1248 
1249 	hci_conn_hold(sco);
1250 
1251 	sco->setting = setting;
1252 
1253 	if (acl->state == BT_CONNECTED &&
1254 	    (sco->state == BT_OPEN || sco->state == BT_CLOSED)) {
1255 		set_bit(HCI_CONN_POWER_SAVE, &acl->flags);
1256 		hci_conn_enter_active_mode(acl, BT_POWER_FORCE_ACTIVE_ON);
1257 
1258 		if (test_bit(HCI_CONN_MODE_CHANGE_PEND, &acl->flags)) {
1259 			/* defer SCO setup until mode change completed */
1260 			set_bit(HCI_CONN_SCO_SETUP_PEND, &acl->flags);
1261 			return sco;
1262 		}
1263 
1264 		hci_sco_setup(acl, 0x00);
1265 	}
1266 
1267 	return sco;
1268 }
1269 
1270 /* Check link security requirement */
1271 int hci_conn_check_link_mode(struct hci_conn *conn)
1272 {
1273 	BT_DBG("hcon %p", conn);
1274 
1275 	/* In Secure Connections Only mode, it is required that Secure
1276 	 * Connections is used and the link is encrypted with AES-CCM
1277 	 * using a P-256 authenticated combination key.
1278 	 */
1279 	if (hci_dev_test_flag(conn->hdev, HCI_SC_ONLY)) {
1280 		if (!hci_conn_sc_enabled(conn) ||
1281 		    !test_bit(HCI_CONN_AES_CCM, &conn->flags) ||
1282 		    conn->key_type != HCI_LK_AUTH_COMBINATION_P256)
1283 			return 0;
1284 	}
1285 
1286 	if (hci_conn_ssp_enabled(conn) &&
1287 	    !test_bit(HCI_CONN_ENCRYPT, &conn->flags))
1288 		return 0;
1289 
1290 	return 1;
1291 }
1292 
1293 /* Authenticate remote device */
1294 static int hci_conn_auth(struct hci_conn *conn, __u8 sec_level, __u8 auth_type)
1295 {
1296 	BT_DBG("hcon %p", conn);
1297 
1298 	if (conn->pending_sec_level > sec_level)
1299 		sec_level = conn->pending_sec_level;
1300 
1301 	if (sec_level > conn->sec_level)
1302 		conn->pending_sec_level = sec_level;
1303 	else if (test_bit(HCI_CONN_AUTH, &conn->flags))
1304 		return 1;
1305 
1306 	/* Make sure we preserve an existing MITM requirement*/
1307 	auth_type |= (conn->auth_type & 0x01);
1308 
1309 	conn->auth_type = auth_type;
1310 
1311 	if (!test_and_set_bit(HCI_CONN_AUTH_PEND, &conn->flags)) {
1312 		struct hci_cp_auth_requested cp;
1313 
1314 		cp.handle = cpu_to_le16(conn->handle);
1315 		hci_send_cmd(conn->hdev, HCI_OP_AUTH_REQUESTED,
1316 			     sizeof(cp), &cp);
1317 
1318 		/* If we're already encrypted set the REAUTH_PEND flag,
1319 		 * otherwise set the ENCRYPT_PEND.
1320 		 */
1321 		if (test_bit(HCI_CONN_ENCRYPT, &conn->flags))
1322 			set_bit(HCI_CONN_REAUTH_PEND, &conn->flags);
1323 		else
1324 			set_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags);
1325 	}
1326 
1327 	return 0;
1328 }
1329 
1330 /* Encrypt the the link */
1331 static void hci_conn_encrypt(struct hci_conn *conn)
1332 {
1333 	BT_DBG("hcon %p", conn);
1334 
1335 	if (!test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags)) {
1336 		struct hci_cp_set_conn_encrypt cp;
1337 		cp.handle  = cpu_to_le16(conn->handle);
1338 		cp.encrypt = 0x01;
1339 		hci_send_cmd(conn->hdev, HCI_OP_SET_CONN_ENCRYPT, sizeof(cp),
1340 			     &cp);
1341 	}
1342 }
1343 
1344 /* Enable security */
1345 int hci_conn_security(struct hci_conn *conn, __u8 sec_level, __u8 auth_type,
1346 		      bool initiator)
1347 {
1348 	BT_DBG("hcon %p", conn);
1349 
1350 	if (conn->type == LE_LINK)
1351 		return smp_conn_security(conn, sec_level);
1352 
1353 	/* For sdp we don't need the link key. */
1354 	if (sec_level == BT_SECURITY_SDP)
1355 		return 1;
1356 
1357 	/* For non 2.1 devices and low security level we don't need the link
1358 	   key. */
1359 	if (sec_level == BT_SECURITY_LOW && !hci_conn_ssp_enabled(conn))
1360 		return 1;
1361 
1362 	/* For other security levels we need the link key. */
1363 	if (!test_bit(HCI_CONN_AUTH, &conn->flags))
1364 		goto auth;
1365 
1366 	/* An authenticated FIPS approved combination key has sufficient
1367 	 * security for security level 4. */
1368 	if (conn->key_type == HCI_LK_AUTH_COMBINATION_P256 &&
1369 	    sec_level == BT_SECURITY_FIPS)
1370 		goto encrypt;
1371 
1372 	/* An authenticated combination key has sufficient security for
1373 	   security level 3. */
1374 	if ((conn->key_type == HCI_LK_AUTH_COMBINATION_P192 ||
1375 	     conn->key_type == HCI_LK_AUTH_COMBINATION_P256) &&
1376 	    sec_level == BT_SECURITY_HIGH)
1377 		goto encrypt;
1378 
1379 	/* An unauthenticated combination key has sufficient security for
1380 	   security level 1 and 2. */
1381 	if ((conn->key_type == HCI_LK_UNAUTH_COMBINATION_P192 ||
1382 	     conn->key_type == HCI_LK_UNAUTH_COMBINATION_P256) &&
1383 	    (sec_level == BT_SECURITY_MEDIUM || sec_level == BT_SECURITY_LOW))
1384 		goto encrypt;
1385 
1386 	/* A combination key has always sufficient security for the security
1387 	   levels 1 or 2. High security level requires the combination key
1388 	   is generated using maximum PIN code length (16).
1389 	   For pre 2.1 units. */
1390 	if (conn->key_type == HCI_LK_COMBINATION &&
1391 	    (sec_level == BT_SECURITY_MEDIUM || sec_level == BT_SECURITY_LOW ||
1392 	     conn->pin_length == 16))
1393 		goto encrypt;
1394 
1395 auth:
1396 	if (test_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags))
1397 		return 0;
1398 
1399 	if (initiator)
1400 		set_bit(HCI_CONN_AUTH_INITIATOR, &conn->flags);
1401 
1402 	if (!hci_conn_auth(conn, sec_level, auth_type))
1403 		return 0;
1404 
1405 encrypt:
1406 	if (test_bit(HCI_CONN_ENCRYPT, &conn->flags)) {
1407 		/* Ensure that the encryption key size has been read,
1408 		 * otherwise stall the upper layer responses.
1409 		 */
1410 		if (!conn->enc_key_size)
1411 			return 0;
1412 
1413 		/* Nothing else needed, all requirements are met */
1414 		return 1;
1415 	}
1416 
1417 	hci_conn_encrypt(conn);
1418 	return 0;
1419 }
1420 EXPORT_SYMBOL(hci_conn_security);
1421 
1422 /* Check secure link requirement */
1423 int hci_conn_check_secure(struct hci_conn *conn, __u8 sec_level)
1424 {
1425 	BT_DBG("hcon %p", conn);
1426 
1427 	/* Accept if non-secure or higher security level is required */
1428 	if (sec_level != BT_SECURITY_HIGH && sec_level != BT_SECURITY_FIPS)
1429 		return 1;
1430 
1431 	/* Accept if secure or higher security level is already present */
1432 	if (conn->sec_level == BT_SECURITY_HIGH ||
1433 	    conn->sec_level == BT_SECURITY_FIPS)
1434 		return 1;
1435 
1436 	/* Reject not secure link */
1437 	return 0;
1438 }
1439 EXPORT_SYMBOL(hci_conn_check_secure);
1440 
1441 /* Switch role */
1442 int hci_conn_switch_role(struct hci_conn *conn, __u8 role)
1443 {
1444 	BT_DBG("hcon %p", conn);
1445 
1446 	if (role == conn->role)
1447 		return 1;
1448 
1449 	if (!test_and_set_bit(HCI_CONN_RSWITCH_PEND, &conn->flags)) {
1450 		struct hci_cp_switch_role cp;
1451 		bacpy(&cp.bdaddr, &conn->dst);
1452 		cp.role = role;
1453 		hci_send_cmd(conn->hdev, HCI_OP_SWITCH_ROLE, sizeof(cp), &cp);
1454 	}
1455 
1456 	return 0;
1457 }
1458 EXPORT_SYMBOL(hci_conn_switch_role);
1459 
1460 /* Enter active mode */
1461 void hci_conn_enter_active_mode(struct hci_conn *conn, __u8 force_active)
1462 {
1463 	struct hci_dev *hdev = conn->hdev;
1464 
1465 	BT_DBG("hcon %p mode %d", conn, conn->mode);
1466 
1467 	if (conn->mode != HCI_CM_SNIFF)
1468 		goto timer;
1469 
1470 	if (!test_bit(HCI_CONN_POWER_SAVE, &conn->flags) && !force_active)
1471 		goto timer;
1472 
1473 	if (!test_and_set_bit(HCI_CONN_MODE_CHANGE_PEND, &conn->flags)) {
1474 		struct hci_cp_exit_sniff_mode cp;
1475 		cp.handle = cpu_to_le16(conn->handle);
1476 		hci_send_cmd(hdev, HCI_OP_EXIT_SNIFF_MODE, sizeof(cp), &cp);
1477 	}
1478 
1479 timer:
1480 	if (hdev->idle_timeout > 0)
1481 		queue_delayed_work(hdev->workqueue, &conn->idle_work,
1482 				   msecs_to_jiffies(hdev->idle_timeout));
1483 }
1484 
1485 /* Drop all connection on the device */
1486 void hci_conn_hash_flush(struct hci_dev *hdev)
1487 {
1488 	struct hci_conn_hash *h = &hdev->conn_hash;
1489 	struct hci_conn *c, *n;
1490 
1491 	BT_DBG("hdev %s", hdev->name);
1492 
1493 	list_for_each_entry_safe(c, n, &h->list, list) {
1494 		c->state = BT_CLOSED;
1495 
1496 		hci_disconn_cfm(c, HCI_ERROR_LOCAL_HOST_TERM);
1497 		hci_conn_del(c);
1498 	}
1499 }
1500 
1501 /* Check pending connect attempts */
1502 void hci_conn_check_pending(struct hci_dev *hdev)
1503 {
1504 	struct hci_conn *conn;
1505 
1506 	BT_DBG("hdev %s", hdev->name);
1507 
1508 	hci_dev_lock(hdev);
1509 
1510 	conn = hci_conn_hash_lookup_state(hdev, ACL_LINK, BT_CONNECT2);
1511 	if (conn)
1512 		hci_acl_create_connection(conn);
1513 
1514 	hci_dev_unlock(hdev);
1515 }
1516 
1517 static u32 get_link_mode(struct hci_conn *conn)
1518 {
1519 	u32 link_mode = 0;
1520 
1521 	if (conn->role == HCI_ROLE_MASTER)
1522 		link_mode |= HCI_LM_MASTER;
1523 
1524 	if (test_bit(HCI_CONN_ENCRYPT, &conn->flags))
1525 		link_mode |= HCI_LM_ENCRYPT;
1526 
1527 	if (test_bit(HCI_CONN_AUTH, &conn->flags))
1528 		link_mode |= HCI_LM_AUTH;
1529 
1530 	if (test_bit(HCI_CONN_SECURE, &conn->flags))
1531 		link_mode |= HCI_LM_SECURE;
1532 
1533 	if (test_bit(HCI_CONN_FIPS, &conn->flags))
1534 		link_mode |= HCI_LM_FIPS;
1535 
1536 	return link_mode;
1537 }
1538 
1539 int hci_get_conn_list(void __user *arg)
1540 {
1541 	struct hci_conn *c;
1542 	struct hci_conn_list_req req, *cl;
1543 	struct hci_conn_info *ci;
1544 	struct hci_dev *hdev;
1545 	int n = 0, size, err;
1546 
1547 	if (copy_from_user(&req, arg, sizeof(req)))
1548 		return -EFAULT;
1549 
1550 	if (!req.conn_num || req.conn_num > (PAGE_SIZE * 2) / sizeof(*ci))
1551 		return -EINVAL;
1552 
1553 	size = sizeof(req) + req.conn_num * sizeof(*ci);
1554 
1555 	cl = kmalloc(size, GFP_KERNEL);
1556 	if (!cl)
1557 		return -ENOMEM;
1558 
1559 	hdev = hci_dev_get(req.dev_id);
1560 	if (!hdev) {
1561 		kfree(cl);
1562 		return -ENODEV;
1563 	}
1564 
1565 	ci = cl->conn_info;
1566 
1567 	hci_dev_lock(hdev);
1568 	list_for_each_entry(c, &hdev->conn_hash.list, list) {
1569 		bacpy(&(ci + n)->bdaddr, &c->dst);
1570 		(ci + n)->handle = c->handle;
1571 		(ci + n)->type  = c->type;
1572 		(ci + n)->out   = c->out;
1573 		(ci + n)->state = c->state;
1574 		(ci + n)->link_mode = get_link_mode(c);
1575 		if (++n >= req.conn_num)
1576 			break;
1577 	}
1578 	hci_dev_unlock(hdev);
1579 
1580 	cl->dev_id = hdev->id;
1581 	cl->conn_num = n;
1582 	size = sizeof(req) + n * sizeof(*ci);
1583 
1584 	hci_dev_put(hdev);
1585 
1586 	err = copy_to_user(arg, cl, size);
1587 	kfree(cl);
1588 
1589 	return err ? -EFAULT : 0;
1590 }
1591 
1592 int hci_get_conn_info(struct hci_dev *hdev, void __user *arg)
1593 {
1594 	struct hci_conn_info_req req;
1595 	struct hci_conn_info ci;
1596 	struct hci_conn *conn;
1597 	char __user *ptr = arg + sizeof(req);
1598 
1599 	if (copy_from_user(&req, arg, sizeof(req)))
1600 		return -EFAULT;
1601 
1602 	hci_dev_lock(hdev);
1603 	conn = hci_conn_hash_lookup_ba(hdev, req.type, &req.bdaddr);
1604 	if (conn) {
1605 		bacpy(&ci.bdaddr, &conn->dst);
1606 		ci.handle = conn->handle;
1607 		ci.type  = conn->type;
1608 		ci.out   = conn->out;
1609 		ci.state = conn->state;
1610 		ci.link_mode = get_link_mode(conn);
1611 	}
1612 	hci_dev_unlock(hdev);
1613 
1614 	if (!conn)
1615 		return -ENOENT;
1616 
1617 	return copy_to_user(ptr, &ci, sizeof(ci)) ? -EFAULT : 0;
1618 }
1619 
1620 int hci_get_auth_info(struct hci_dev *hdev, void __user *arg)
1621 {
1622 	struct hci_auth_info_req req;
1623 	struct hci_conn *conn;
1624 
1625 	if (copy_from_user(&req, arg, sizeof(req)))
1626 		return -EFAULT;
1627 
1628 	hci_dev_lock(hdev);
1629 	conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, &req.bdaddr);
1630 	if (conn)
1631 		req.type = conn->auth_type;
1632 	hci_dev_unlock(hdev);
1633 
1634 	if (!conn)
1635 		return -ENOENT;
1636 
1637 	return copy_to_user(arg, &req, sizeof(req)) ? -EFAULT : 0;
1638 }
1639 
1640 struct hci_chan *hci_chan_create(struct hci_conn *conn)
1641 {
1642 	struct hci_dev *hdev = conn->hdev;
1643 	struct hci_chan *chan;
1644 
1645 	BT_DBG("%s hcon %p", hdev->name, conn);
1646 
1647 	if (test_bit(HCI_CONN_DROP, &conn->flags)) {
1648 		BT_DBG("Refusing to create new hci_chan");
1649 		return NULL;
1650 	}
1651 
1652 	chan = kzalloc(sizeof(*chan), GFP_KERNEL);
1653 	if (!chan)
1654 		return NULL;
1655 
1656 	chan->conn = hci_conn_get(conn);
1657 	skb_queue_head_init(&chan->data_q);
1658 	chan->state = BT_CONNECTED;
1659 
1660 	list_add_rcu(&chan->list, &conn->chan_list);
1661 
1662 	return chan;
1663 }
1664 
1665 void hci_chan_del(struct hci_chan *chan)
1666 {
1667 	struct hci_conn *conn = chan->conn;
1668 	struct hci_dev *hdev = conn->hdev;
1669 
1670 	BT_DBG("%s hcon %p chan %p", hdev->name, conn, chan);
1671 
1672 	list_del_rcu(&chan->list);
1673 
1674 	synchronize_rcu();
1675 
1676 	/* Prevent new hci_chan's to be created for this hci_conn */
1677 	set_bit(HCI_CONN_DROP, &conn->flags);
1678 
1679 	hci_conn_put(conn);
1680 
1681 	skb_queue_purge(&chan->data_q);
1682 	kfree(chan);
1683 }
1684 
1685 void hci_chan_list_flush(struct hci_conn *conn)
1686 {
1687 	struct hci_chan *chan, *n;
1688 
1689 	BT_DBG("hcon %p", conn);
1690 
1691 	list_for_each_entry_safe(chan, n, &conn->chan_list, list)
1692 		hci_chan_del(chan);
1693 }
1694 
1695 static struct hci_chan *__hci_chan_lookup_handle(struct hci_conn *hcon,
1696 						 __u16 handle)
1697 {
1698 	struct hci_chan *hchan;
1699 
1700 	list_for_each_entry(hchan, &hcon->chan_list, list) {
1701 		if (hchan->handle == handle)
1702 			return hchan;
1703 	}
1704 
1705 	return NULL;
1706 }
1707 
1708 struct hci_chan *hci_chan_lookup_handle(struct hci_dev *hdev, __u16 handle)
1709 {
1710 	struct hci_conn_hash *h = &hdev->conn_hash;
1711 	struct hci_conn *hcon;
1712 	struct hci_chan *hchan = NULL;
1713 
1714 	rcu_read_lock();
1715 
1716 	list_for_each_entry_rcu(hcon, &h->list, list) {
1717 		hchan = __hci_chan_lookup_handle(hcon, handle);
1718 		if (hchan)
1719 			break;
1720 	}
1721 
1722 	rcu_read_unlock();
1723 
1724 	return hchan;
1725 }
1726