xref: /linux/net/bluetooth/hci_conn.c (revision 7aacf86b75bc5523d20fd9127104384fce51ce9c)
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_ERR("HCI request failed to create LE connection: status 0x%2.2x",
733 	       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 hci_req_add_le_create_conn(struct hci_request *req,
752 				       struct hci_conn *conn)
753 {
754 	struct hci_cp_le_create_conn cp;
755 	struct hci_dev *hdev = conn->hdev;
756 	u8 own_addr_type;
757 
758 	/* Update random address, but set require_privacy to false so
759 	 * that we never connect with an non-resolvable address.
760 	 */
761 	if (hci_update_random_address(req, false, conn_use_rpa(conn),
762 				      &own_addr_type))
763 		return;
764 
765 	memset(&cp, 0, sizeof(cp));
766 
767 	/* Set window to be the same value as the interval to enable
768 	 * continuous scanning.
769 	 */
770 	cp.scan_interval = cpu_to_le16(hdev->le_scan_interval);
771 	cp.scan_window = cp.scan_interval;
772 
773 	bacpy(&cp.peer_addr, &conn->dst);
774 	cp.peer_addr_type = conn->dst_type;
775 	cp.own_address_type = own_addr_type;
776 	cp.conn_interval_min = cpu_to_le16(conn->le_conn_min_interval);
777 	cp.conn_interval_max = cpu_to_le16(conn->le_conn_max_interval);
778 	cp.conn_latency = cpu_to_le16(conn->le_conn_latency);
779 	cp.supervision_timeout = cpu_to_le16(conn->le_supv_timeout);
780 	cp.min_ce_len = cpu_to_le16(0x0000);
781 	cp.max_ce_len = cpu_to_le16(0x0000);
782 
783 	hci_req_add(req, HCI_OP_LE_CREATE_CONN, sizeof(cp), &cp);
784 
785 	conn->state = BT_CONNECT;
786 	clear_bit(HCI_CONN_SCANNING, &conn->flags);
787 }
788 
789 static void hci_req_directed_advertising(struct hci_request *req,
790 					 struct hci_conn *conn)
791 {
792 	struct hci_dev *hdev = req->hdev;
793 	struct hci_cp_le_set_adv_param cp;
794 	u8 own_addr_type;
795 	u8 enable;
796 
797 	/* Clear the HCI_LE_ADV bit temporarily so that the
798 	 * hci_update_random_address knows that it's safe to go ahead
799 	 * and write a new random address. The flag will be set back on
800 	 * as soon as the SET_ADV_ENABLE HCI command completes.
801 	 */
802 	hci_dev_clear_flag(hdev, HCI_LE_ADV);
803 
804 	/* Set require_privacy to false so that the remote device has a
805 	 * chance of identifying us.
806 	 */
807 	if (hci_update_random_address(req, false, conn_use_rpa(conn),
808 				      &own_addr_type) < 0)
809 		return;
810 
811 	memset(&cp, 0, sizeof(cp));
812 	cp.type = LE_ADV_DIRECT_IND;
813 	cp.own_address_type = own_addr_type;
814 	cp.direct_addr_type = conn->dst_type;
815 	bacpy(&cp.direct_addr, &conn->dst);
816 	cp.channel_map = hdev->le_adv_channel_map;
817 
818 	hci_req_add(req, HCI_OP_LE_SET_ADV_PARAM, sizeof(cp), &cp);
819 
820 	enable = 0x01;
821 	hci_req_add(req, HCI_OP_LE_SET_ADV_ENABLE, sizeof(enable), &enable);
822 
823 	conn->state = BT_CONNECT;
824 }
825 
826 struct hci_conn *hci_connect_le(struct hci_dev *hdev, bdaddr_t *dst,
827 				u8 dst_type, u8 sec_level, u16 conn_timeout,
828 				u8 role)
829 {
830 	struct hci_conn_params *params;
831 	struct hci_conn *conn;
832 	struct smp_irk *irk;
833 	struct hci_request req;
834 	int err;
835 
836 	/* Let's make sure that le is enabled.*/
837 	if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED)) {
838 		if (lmp_le_capable(hdev))
839 			return ERR_PTR(-ECONNREFUSED);
840 
841 		return ERR_PTR(-EOPNOTSUPP);
842 	}
843 
844 	/* Since the controller supports only one LE connection attempt at a
845 	 * time, we return -EBUSY if there is any connection attempt running.
846 	 */
847 	if (hci_lookup_le_connect(hdev))
848 		return ERR_PTR(-EBUSY);
849 
850 	/* If there's already a connection object but it's not in
851 	 * scanning state it means it must already be established, in
852 	 * which case we can't do anything else except report a failure
853 	 * to connect.
854 	 */
855 	conn = hci_conn_hash_lookup_le(hdev, dst, dst_type);
856 	if (conn && !test_bit(HCI_CONN_SCANNING, &conn->flags)) {
857 		return ERR_PTR(-EBUSY);
858 	}
859 
860 	/* When given an identity address with existing identity
861 	 * resolving key, the connection needs to be established
862 	 * to a resolvable random address.
863 	 *
864 	 * Storing the resolvable random address is required here
865 	 * to handle connection failures. The address will later
866 	 * be resolved back into the original identity address
867 	 * from the connect request.
868 	 */
869 	irk = hci_find_irk_by_addr(hdev, dst, dst_type);
870 	if (irk && bacmp(&irk->rpa, BDADDR_ANY)) {
871 		dst = &irk->rpa;
872 		dst_type = ADDR_LE_DEV_RANDOM;
873 	}
874 
875 	if (conn) {
876 		bacpy(&conn->dst, dst);
877 	} else {
878 		conn = hci_conn_add(hdev, LE_LINK, dst, role);
879 		if (!conn)
880 			return ERR_PTR(-ENOMEM);
881 		hci_conn_hold(conn);
882 		conn->pending_sec_level = sec_level;
883 	}
884 
885 	conn->dst_type = dst_type;
886 	conn->sec_level = BT_SECURITY_LOW;
887 	conn->conn_timeout = conn_timeout;
888 
889 	hci_req_init(&req, hdev);
890 
891 	/* Disable advertising if we're active. For master role
892 	 * connections most controllers will refuse to connect if
893 	 * advertising is enabled, and for slave role connections we
894 	 * anyway have to disable it in order to start directed
895 	 * advertising.
896 	 */
897 	if (hci_dev_test_flag(hdev, HCI_LE_ADV)) {
898 		u8 enable = 0x00;
899 		hci_req_add(&req, HCI_OP_LE_SET_ADV_ENABLE, sizeof(enable),
900 			    &enable);
901 	}
902 
903 	/* If requested to connect as slave use directed advertising */
904 	if (conn->role == HCI_ROLE_SLAVE) {
905 		/* If we're active scanning most controllers are unable
906 		 * to initiate advertising. Simply reject the attempt.
907 		 */
908 		if (hci_dev_test_flag(hdev, HCI_LE_SCAN) &&
909 		    hdev->le_scan_type == LE_SCAN_ACTIVE) {
910 			skb_queue_purge(&req.cmd_q);
911 			hci_conn_del(conn);
912 			return ERR_PTR(-EBUSY);
913 		}
914 
915 		hci_req_directed_advertising(&req, conn);
916 		goto create_conn;
917 	}
918 
919 	params = hci_conn_params_lookup(hdev, &conn->dst, conn->dst_type);
920 	if (params) {
921 		conn->le_conn_min_interval = params->conn_min_interval;
922 		conn->le_conn_max_interval = params->conn_max_interval;
923 		conn->le_conn_latency = params->conn_latency;
924 		conn->le_supv_timeout = params->supervision_timeout;
925 	} else {
926 		conn->le_conn_min_interval = hdev->le_conn_min_interval;
927 		conn->le_conn_max_interval = hdev->le_conn_max_interval;
928 		conn->le_conn_latency = hdev->le_conn_latency;
929 		conn->le_supv_timeout = hdev->le_supv_timeout;
930 	}
931 
932 	/* If controller is scanning, we stop it since some controllers are
933 	 * not able to scan and connect at the same time. Also set the
934 	 * HCI_LE_SCAN_INTERRUPTED flag so that the command complete
935 	 * handler for scan disabling knows to set the correct discovery
936 	 * state.
937 	 */
938 	if (hci_dev_test_flag(hdev, HCI_LE_SCAN)) {
939 		hci_req_add_le_scan_disable(&req);
940 		hci_dev_set_flag(hdev, HCI_LE_SCAN_INTERRUPTED);
941 	}
942 
943 	hci_req_add_le_create_conn(&req, conn);
944 
945 create_conn:
946 	err = hci_req_run(&req, create_le_conn_complete);
947 	if (err) {
948 		hci_conn_del(conn);
949 		return ERR_PTR(err);
950 	}
951 
952 	return conn;
953 }
954 
955 static bool is_connected(struct hci_dev *hdev, bdaddr_t *addr, u8 type)
956 {
957 	struct hci_conn *conn;
958 
959 	conn = hci_conn_hash_lookup_le(hdev, addr, type);
960 	if (!conn)
961 		return false;
962 
963 	if (conn->state != BT_CONNECTED)
964 		return false;
965 
966 	return true;
967 }
968 
969 /* This function requires the caller holds hdev->lock */
970 static int hci_explicit_conn_params_set(struct hci_dev *hdev,
971 					bdaddr_t *addr, u8 addr_type)
972 {
973 	struct hci_conn_params *params;
974 
975 	if (is_connected(hdev, addr, addr_type))
976 		return -EISCONN;
977 
978 	params = hci_conn_params_lookup(hdev, addr, addr_type);
979 	if (!params) {
980 		params = hci_conn_params_add(hdev, addr, addr_type);
981 		if (!params)
982 			return -ENOMEM;
983 
984 		/* If we created new params, mark them to be deleted in
985 		 * hci_connect_le_scan_cleanup. It's different case than
986 		 * existing disabled params, those will stay after cleanup.
987 		 */
988 		params->auto_connect = HCI_AUTO_CONN_EXPLICIT;
989 	}
990 
991 	/* We're trying to connect, so make sure params are at pend_le_conns */
992 	if (params->auto_connect == HCI_AUTO_CONN_DISABLED ||
993 	    params->auto_connect == HCI_AUTO_CONN_REPORT ||
994 	    params->auto_connect == HCI_AUTO_CONN_EXPLICIT) {
995 		list_del_init(&params->action);
996 		list_add(&params->action, &hdev->pend_le_conns);
997 	}
998 
999 	params->explicit_connect = true;
1000 
1001 	BT_DBG("addr %pMR (type %u) auto_connect %u", addr, addr_type,
1002 	       params->auto_connect);
1003 
1004 	return 0;
1005 }
1006 
1007 /* This function requires the caller holds hdev->lock */
1008 struct hci_conn *hci_connect_le_scan(struct hci_dev *hdev, bdaddr_t *dst,
1009 				     u8 dst_type, u8 sec_level,
1010 				     u16 conn_timeout)
1011 {
1012 	struct hci_conn *conn;
1013 
1014 	/* Let's make sure that le is enabled.*/
1015 	if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED)) {
1016 		if (lmp_le_capable(hdev))
1017 			return ERR_PTR(-ECONNREFUSED);
1018 
1019 		return ERR_PTR(-EOPNOTSUPP);
1020 	}
1021 
1022 	/* Some devices send ATT messages as soon as the physical link is
1023 	 * established. To be able to handle these ATT messages, the user-
1024 	 * space first establishes the connection and then starts the pairing
1025 	 * process.
1026 	 *
1027 	 * So if a hci_conn object already exists for the following connection
1028 	 * attempt, we simply update pending_sec_level and auth_type fields
1029 	 * and return the object found.
1030 	 */
1031 	conn = hci_conn_hash_lookup_le(hdev, dst, dst_type);
1032 	if (conn) {
1033 		if (conn->pending_sec_level < sec_level)
1034 			conn->pending_sec_level = sec_level;
1035 		goto done;
1036 	}
1037 
1038 	BT_DBG("requesting refresh of dst_addr");
1039 
1040 	conn = hci_conn_add(hdev, LE_LINK, dst, HCI_ROLE_MASTER);
1041 	if (!conn)
1042 		return ERR_PTR(-ENOMEM);
1043 
1044 	if (hci_explicit_conn_params_set(hdev, dst, dst_type) < 0)
1045 		return ERR_PTR(-EBUSY);
1046 
1047 	conn->state = BT_CONNECT;
1048 	set_bit(HCI_CONN_SCANNING, &conn->flags);
1049 	conn->dst_type = dst_type;
1050 	conn->sec_level = BT_SECURITY_LOW;
1051 	conn->pending_sec_level = sec_level;
1052 	conn->conn_timeout = conn_timeout;
1053 
1054 	hci_update_background_scan(hdev);
1055 
1056 done:
1057 	hci_conn_hold(conn);
1058 	return conn;
1059 }
1060 
1061 struct hci_conn *hci_connect_acl(struct hci_dev *hdev, bdaddr_t *dst,
1062 				 u8 sec_level, u8 auth_type)
1063 {
1064 	struct hci_conn *acl;
1065 
1066 	if (!hci_dev_test_flag(hdev, HCI_BREDR_ENABLED)) {
1067 		if (lmp_bredr_capable(hdev))
1068 			return ERR_PTR(-ECONNREFUSED);
1069 
1070 		return ERR_PTR(-EOPNOTSUPP);
1071 	}
1072 
1073 	acl = hci_conn_hash_lookup_ba(hdev, ACL_LINK, dst);
1074 	if (!acl) {
1075 		acl = hci_conn_add(hdev, ACL_LINK, dst, HCI_ROLE_MASTER);
1076 		if (!acl)
1077 			return ERR_PTR(-ENOMEM);
1078 	}
1079 
1080 	hci_conn_hold(acl);
1081 
1082 	if (acl->state == BT_OPEN || acl->state == BT_CLOSED) {
1083 		acl->sec_level = BT_SECURITY_LOW;
1084 		acl->pending_sec_level = sec_level;
1085 		acl->auth_type = auth_type;
1086 		hci_acl_create_connection(acl);
1087 	}
1088 
1089 	return acl;
1090 }
1091 
1092 struct hci_conn *hci_connect_sco(struct hci_dev *hdev, int type, bdaddr_t *dst,
1093 				 __u16 setting)
1094 {
1095 	struct hci_conn *acl;
1096 	struct hci_conn *sco;
1097 
1098 	acl = hci_connect_acl(hdev, dst, BT_SECURITY_LOW, HCI_AT_NO_BONDING);
1099 	if (IS_ERR(acl))
1100 		return acl;
1101 
1102 	sco = hci_conn_hash_lookup_ba(hdev, type, dst);
1103 	if (!sco) {
1104 		sco = hci_conn_add(hdev, type, dst, HCI_ROLE_MASTER);
1105 		if (!sco) {
1106 			hci_conn_drop(acl);
1107 			return ERR_PTR(-ENOMEM);
1108 		}
1109 	}
1110 
1111 	acl->link = sco;
1112 	sco->link = acl;
1113 
1114 	hci_conn_hold(sco);
1115 
1116 	sco->setting = setting;
1117 
1118 	if (acl->state == BT_CONNECTED &&
1119 	    (sco->state == BT_OPEN || sco->state == BT_CLOSED)) {
1120 		set_bit(HCI_CONN_POWER_SAVE, &acl->flags);
1121 		hci_conn_enter_active_mode(acl, BT_POWER_FORCE_ACTIVE_ON);
1122 
1123 		if (test_bit(HCI_CONN_MODE_CHANGE_PEND, &acl->flags)) {
1124 			/* defer SCO setup until mode change completed */
1125 			set_bit(HCI_CONN_SCO_SETUP_PEND, &acl->flags);
1126 			return sco;
1127 		}
1128 
1129 		hci_sco_setup(acl, 0x00);
1130 	}
1131 
1132 	return sco;
1133 }
1134 
1135 /* Check link security requirement */
1136 int hci_conn_check_link_mode(struct hci_conn *conn)
1137 {
1138 	BT_DBG("hcon %p", conn);
1139 
1140 	/* In Secure Connections Only mode, it is required that Secure
1141 	 * Connections is used and the link is encrypted with AES-CCM
1142 	 * using a P-256 authenticated combination key.
1143 	 */
1144 	if (hci_dev_test_flag(conn->hdev, HCI_SC_ONLY)) {
1145 		if (!hci_conn_sc_enabled(conn) ||
1146 		    !test_bit(HCI_CONN_AES_CCM, &conn->flags) ||
1147 		    conn->key_type != HCI_LK_AUTH_COMBINATION_P256)
1148 			return 0;
1149 	}
1150 
1151 	if (hci_conn_ssp_enabled(conn) &&
1152 	    !test_bit(HCI_CONN_ENCRYPT, &conn->flags))
1153 		return 0;
1154 
1155 	return 1;
1156 }
1157 
1158 /* Authenticate remote device */
1159 static int hci_conn_auth(struct hci_conn *conn, __u8 sec_level, __u8 auth_type)
1160 {
1161 	BT_DBG("hcon %p", conn);
1162 
1163 	if (conn->pending_sec_level > sec_level)
1164 		sec_level = conn->pending_sec_level;
1165 
1166 	if (sec_level > conn->sec_level)
1167 		conn->pending_sec_level = sec_level;
1168 	else if (test_bit(HCI_CONN_AUTH, &conn->flags))
1169 		return 1;
1170 
1171 	/* Make sure we preserve an existing MITM requirement*/
1172 	auth_type |= (conn->auth_type & 0x01);
1173 
1174 	conn->auth_type = auth_type;
1175 
1176 	if (!test_and_set_bit(HCI_CONN_AUTH_PEND, &conn->flags)) {
1177 		struct hci_cp_auth_requested cp;
1178 
1179 		cp.handle = cpu_to_le16(conn->handle);
1180 		hci_send_cmd(conn->hdev, HCI_OP_AUTH_REQUESTED,
1181 			     sizeof(cp), &cp);
1182 
1183 		/* If we're already encrypted set the REAUTH_PEND flag,
1184 		 * otherwise set the ENCRYPT_PEND.
1185 		 */
1186 		if (test_bit(HCI_CONN_ENCRYPT, &conn->flags))
1187 			set_bit(HCI_CONN_REAUTH_PEND, &conn->flags);
1188 		else
1189 			set_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags);
1190 	}
1191 
1192 	return 0;
1193 }
1194 
1195 /* Encrypt the the link */
1196 static void hci_conn_encrypt(struct hci_conn *conn)
1197 {
1198 	BT_DBG("hcon %p", conn);
1199 
1200 	if (!test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags)) {
1201 		struct hci_cp_set_conn_encrypt cp;
1202 		cp.handle  = cpu_to_le16(conn->handle);
1203 		cp.encrypt = 0x01;
1204 		hci_send_cmd(conn->hdev, HCI_OP_SET_CONN_ENCRYPT, sizeof(cp),
1205 			     &cp);
1206 	}
1207 }
1208 
1209 /* Enable security */
1210 int hci_conn_security(struct hci_conn *conn, __u8 sec_level, __u8 auth_type,
1211 		      bool initiator)
1212 {
1213 	BT_DBG("hcon %p", conn);
1214 
1215 	if (conn->type == LE_LINK)
1216 		return smp_conn_security(conn, sec_level);
1217 
1218 	/* For sdp we don't need the link key. */
1219 	if (sec_level == BT_SECURITY_SDP)
1220 		return 1;
1221 
1222 	/* For non 2.1 devices and low security level we don't need the link
1223 	   key. */
1224 	if (sec_level == BT_SECURITY_LOW && !hci_conn_ssp_enabled(conn))
1225 		return 1;
1226 
1227 	/* For other security levels we need the link key. */
1228 	if (!test_bit(HCI_CONN_AUTH, &conn->flags))
1229 		goto auth;
1230 
1231 	/* An authenticated FIPS approved combination key has sufficient
1232 	 * security for security level 4. */
1233 	if (conn->key_type == HCI_LK_AUTH_COMBINATION_P256 &&
1234 	    sec_level == BT_SECURITY_FIPS)
1235 		goto encrypt;
1236 
1237 	/* An authenticated combination key has sufficient security for
1238 	   security level 3. */
1239 	if ((conn->key_type == HCI_LK_AUTH_COMBINATION_P192 ||
1240 	     conn->key_type == HCI_LK_AUTH_COMBINATION_P256) &&
1241 	    sec_level == BT_SECURITY_HIGH)
1242 		goto encrypt;
1243 
1244 	/* An unauthenticated combination key has sufficient security for
1245 	   security level 1 and 2. */
1246 	if ((conn->key_type == HCI_LK_UNAUTH_COMBINATION_P192 ||
1247 	     conn->key_type == HCI_LK_UNAUTH_COMBINATION_P256) &&
1248 	    (sec_level == BT_SECURITY_MEDIUM || sec_level == BT_SECURITY_LOW))
1249 		goto encrypt;
1250 
1251 	/* A combination key has always sufficient security for the security
1252 	   levels 1 or 2. High security level requires the combination key
1253 	   is generated using maximum PIN code length (16).
1254 	   For pre 2.1 units. */
1255 	if (conn->key_type == HCI_LK_COMBINATION &&
1256 	    (sec_level == BT_SECURITY_MEDIUM || sec_level == BT_SECURITY_LOW ||
1257 	     conn->pin_length == 16))
1258 		goto encrypt;
1259 
1260 auth:
1261 	if (test_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags))
1262 		return 0;
1263 
1264 	if (initiator)
1265 		set_bit(HCI_CONN_AUTH_INITIATOR, &conn->flags);
1266 
1267 	if (!hci_conn_auth(conn, sec_level, auth_type))
1268 		return 0;
1269 
1270 encrypt:
1271 	if (test_bit(HCI_CONN_ENCRYPT, &conn->flags))
1272 		return 1;
1273 
1274 	hci_conn_encrypt(conn);
1275 	return 0;
1276 }
1277 EXPORT_SYMBOL(hci_conn_security);
1278 
1279 /* Check secure link requirement */
1280 int hci_conn_check_secure(struct hci_conn *conn, __u8 sec_level)
1281 {
1282 	BT_DBG("hcon %p", conn);
1283 
1284 	/* Accept if non-secure or higher security level is required */
1285 	if (sec_level != BT_SECURITY_HIGH && sec_level != BT_SECURITY_FIPS)
1286 		return 1;
1287 
1288 	/* Accept if secure or higher security level is already present */
1289 	if (conn->sec_level == BT_SECURITY_HIGH ||
1290 	    conn->sec_level == BT_SECURITY_FIPS)
1291 		return 1;
1292 
1293 	/* Reject not secure link */
1294 	return 0;
1295 }
1296 EXPORT_SYMBOL(hci_conn_check_secure);
1297 
1298 /* Switch role */
1299 int hci_conn_switch_role(struct hci_conn *conn, __u8 role)
1300 {
1301 	BT_DBG("hcon %p", conn);
1302 
1303 	if (role == conn->role)
1304 		return 1;
1305 
1306 	if (!test_and_set_bit(HCI_CONN_RSWITCH_PEND, &conn->flags)) {
1307 		struct hci_cp_switch_role cp;
1308 		bacpy(&cp.bdaddr, &conn->dst);
1309 		cp.role = role;
1310 		hci_send_cmd(conn->hdev, HCI_OP_SWITCH_ROLE, sizeof(cp), &cp);
1311 	}
1312 
1313 	return 0;
1314 }
1315 EXPORT_SYMBOL(hci_conn_switch_role);
1316 
1317 /* Enter active mode */
1318 void hci_conn_enter_active_mode(struct hci_conn *conn, __u8 force_active)
1319 {
1320 	struct hci_dev *hdev = conn->hdev;
1321 
1322 	BT_DBG("hcon %p mode %d", conn, conn->mode);
1323 
1324 	if (conn->mode != HCI_CM_SNIFF)
1325 		goto timer;
1326 
1327 	if (!test_bit(HCI_CONN_POWER_SAVE, &conn->flags) && !force_active)
1328 		goto timer;
1329 
1330 	if (!test_and_set_bit(HCI_CONN_MODE_CHANGE_PEND, &conn->flags)) {
1331 		struct hci_cp_exit_sniff_mode cp;
1332 		cp.handle = cpu_to_le16(conn->handle);
1333 		hci_send_cmd(hdev, HCI_OP_EXIT_SNIFF_MODE, sizeof(cp), &cp);
1334 	}
1335 
1336 timer:
1337 	if (hdev->idle_timeout > 0)
1338 		queue_delayed_work(hdev->workqueue, &conn->idle_work,
1339 				   msecs_to_jiffies(hdev->idle_timeout));
1340 }
1341 
1342 /* Drop all connection on the device */
1343 void hci_conn_hash_flush(struct hci_dev *hdev)
1344 {
1345 	struct hci_conn_hash *h = &hdev->conn_hash;
1346 	struct hci_conn *c, *n;
1347 
1348 	BT_DBG("hdev %s", hdev->name);
1349 
1350 	list_for_each_entry_safe(c, n, &h->list, list) {
1351 		c->state = BT_CLOSED;
1352 
1353 		hci_disconn_cfm(c, HCI_ERROR_LOCAL_HOST_TERM);
1354 		hci_conn_del(c);
1355 	}
1356 }
1357 
1358 /* Check pending connect attempts */
1359 void hci_conn_check_pending(struct hci_dev *hdev)
1360 {
1361 	struct hci_conn *conn;
1362 
1363 	BT_DBG("hdev %s", hdev->name);
1364 
1365 	hci_dev_lock(hdev);
1366 
1367 	conn = hci_conn_hash_lookup_state(hdev, ACL_LINK, BT_CONNECT2);
1368 	if (conn)
1369 		hci_acl_create_connection(conn);
1370 
1371 	hci_dev_unlock(hdev);
1372 }
1373 
1374 static u32 get_link_mode(struct hci_conn *conn)
1375 {
1376 	u32 link_mode = 0;
1377 
1378 	if (conn->role == HCI_ROLE_MASTER)
1379 		link_mode |= HCI_LM_MASTER;
1380 
1381 	if (test_bit(HCI_CONN_ENCRYPT, &conn->flags))
1382 		link_mode |= HCI_LM_ENCRYPT;
1383 
1384 	if (test_bit(HCI_CONN_AUTH, &conn->flags))
1385 		link_mode |= HCI_LM_AUTH;
1386 
1387 	if (test_bit(HCI_CONN_SECURE, &conn->flags))
1388 		link_mode |= HCI_LM_SECURE;
1389 
1390 	if (test_bit(HCI_CONN_FIPS, &conn->flags))
1391 		link_mode |= HCI_LM_FIPS;
1392 
1393 	return link_mode;
1394 }
1395 
1396 int hci_get_conn_list(void __user *arg)
1397 {
1398 	struct hci_conn *c;
1399 	struct hci_conn_list_req req, *cl;
1400 	struct hci_conn_info *ci;
1401 	struct hci_dev *hdev;
1402 	int n = 0, size, err;
1403 
1404 	if (copy_from_user(&req, arg, sizeof(req)))
1405 		return -EFAULT;
1406 
1407 	if (!req.conn_num || req.conn_num > (PAGE_SIZE * 2) / sizeof(*ci))
1408 		return -EINVAL;
1409 
1410 	size = sizeof(req) + req.conn_num * sizeof(*ci);
1411 
1412 	cl = kmalloc(size, GFP_KERNEL);
1413 	if (!cl)
1414 		return -ENOMEM;
1415 
1416 	hdev = hci_dev_get(req.dev_id);
1417 	if (!hdev) {
1418 		kfree(cl);
1419 		return -ENODEV;
1420 	}
1421 
1422 	ci = cl->conn_info;
1423 
1424 	hci_dev_lock(hdev);
1425 	list_for_each_entry(c, &hdev->conn_hash.list, list) {
1426 		bacpy(&(ci + n)->bdaddr, &c->dst);
1427 		(ci + n)->handle = c->handle;
1428 		(ci + n)->type  = c->type;
1429 		(ci + n)->out   = c->out;
1430 		(ci + n)->state = c->state;
1431 		(ci + n)->link_mode = get_link_mode(c);
1432 		if (++n >= req.conn_num)
1433 			break;
1434 	}
1435 	hci_dev_unlock(hdev);
1436 
1437 	cl->dev_id = hdev->id;
1438 	cl->conn_num = n;
1439 	size = sizeof(req) + n * sizeof(*ci);
1440 
1441 	hci_dev_put(hdev);
1442 
1443 	err = copy_to_user(arg, cl, size);
1444 	kfree(cl);
1445 
1446 	return err ? -EFAULT : 0;
1447 }
1448 
1449 int hci_get_conn_info(struct hci_dev *hdev, void __user *arg)
1450 {
1451 	struct hci_conn_info_req req;
1452 	struct hci_conn_info ci;
1453 	struct hci_conn *conn;
1454 	char __user *ptr = arg + sizeof(req);
1455 
1456 	if (copy_from_user(&req, arg, sizeof(req)))
1457 		return -EFAULT;
1458 
1459 	hci_dev_lock(hdev);
1460 	conn = hci_conn_hash_lookup_ba(hdev, req.type, &req.bdaddr);
1461 	if (conn) {
1462 		bacpy(&ci.bdaddr, &conn->dst);
1463 		ci.handle = conn->handle;
1464 		ci.type  = conn->type;
1465 		ci.out   = conn->out;
1466 		ci.state = conn->state;
1467 		ci.link_mode = get_link_mode(conn);
1468 	}
1469 	hci_dev_unlock(hdev);
1470 
1471 	if (!conn)
1472 		return -ENOENT;
1473 
1474 	return copy_to_user(ptr, &ci, sizeof(ci)) ? -EFAULT : 0;
1475 }
1476 
1477 int hci_get_auth_info(struct hci_dev *hdev, void __user *arg)
1478 {
1479 	struct hci_auth_info_req req;
1480 	struct hci_conn *conn;
1481 
1482 	if (copy_from_user(&req, arg, sizeof(req)))
1483 		return -EFAULT;
1484 
1485 	hci_dev_lock(hdev);
1486 	conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, &req.bdaddr);
1487 	if (conn)
1488 		req.type = conn->auth_type;
1489 	hci_dev_unlock(hdev);
1490 
1491 	if (!conn)
1492 		return -ENOENT;
1493 
1494 	return copy_to_user(arg, &req, sizeof(req)) ? -EFAULT : 0;
1495 }
1496 
1497 struct hci_chan *hci_chan_create(struct hci_conn *conn)
1498 {
1499 	struct hci_dev *hdev = conn->hdev;
1500 	struct hci_chan *chan;
1501 
1502 	BT_DBG("%s hcon %p", hdev->name, conn);
1503 
1504 	if (test_bit(HCI_CONN_DROP, &conn->flags)) {
1505 		BT_DBG("Refusing to create new hci_chan");
1506 		return NULL;
1507 	}
1508 
1509 	chan = kzalloc(sizeof(*chan), GFP_KERNEL);
1510 	if (!chan)
1511 		return NULL;
1512 
1513 	chan->conn = hci_conn_get(conn);
1514 	skb_queue_head_init(&chan->data_q);
1515 	chan->state = BT_CONNECTED;
1516 
1517 	list_add_rcu(&chan->list, &conn->chan_list);
1518 
1519 	return chan;
1520 }
1521 
1522 void hci_chan_del(struct hci_chan *chan)
1523 {
1524 	struct hci_conn *conn = chan->conn;
1525 	struct hci_dev *hdev = conn->hdev;
1526 
1527 	BT_DBG("%s hcon %p chan %p", hdev->name, conn, chan);
1528 
1529 	list_del_rcu(&chan->list);
1530 
1531 	synchronize_rcu();
1532 
1533 	/* Prevent new hci_chan's to be created for this hci_conn */
1534 	set_bit(HCI_CONN_DROP, &conn->flags);
1535 
1536 	hci_conn_put(conn);
1537 
1538 	skb_queue_purge(&chan->data_q);
1539 	kfree(chan);
1540 }
1541 
1542 void hci_chan_list_flush(struct hci_conn *conn)
1543 {
1544 	struct hci_chan *chan, *n;
1545 
1546 	BT_DBG("hcon %p", conn);
1547 
1548 	list_for_each_entry_safe(chan, n, &conn->chan_list, list)
1549 		hci_chan_del(chan);
1550 }
1551 
1552 static struct hci_chan *__hci_chan_lookup_handle(struct hci_conn *hcon,
1553 						 __u16 handle)
1554 {
1555 	struct hci_chan *hchan;
1556 
1557 	list_for_each_entry(hchan, &hcon->chan_list, list) {
1558 		if (hchan->handle == handle)
1559 			return hchan;
1560 	}
1561 
1562 	return NULL;
1563 }
1564 
1565 struct hci_chan *hci_chan_lookup_handle(struct hci_dev *hdev, __u16 handle)
1566 {
1567 	struct hci_conn_hash *h = &hdev->conn_hash;
1568 	struct hci_conn *hcon;
1569 	struct hci_chan *hchan = NULL;
1570 
1571 	rcu_read_lock();
1572 
1573 	list_for_each_entry_rcu(hcon, &h->list, list) {
1574 		hchan = __hci_chan_lookup_handle(hcon, handle);
1575 		if (hchan)
1576 			break;
1577 	}
1578 
1579 	rcu_read_unlock();
1580 
1581 	return hchan;
1582 }
1583