xref: /linux/net/bluetooth/hci_conn.c (revision 8c749ce93ee69e789e46b3be98de9e0cbfcf8ed8)
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)
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_BREDR)
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 			if (!bacmp(&d->bdaddr, src)) {
638 				hdev = d; break;
639 			}
640 		} else {
641 			if (bacmp(&d->bdaddr, dst)) {
642 				hdev = d; break;
643 			}
644 		}
645 	}
646 
647 	if (hdev)
648 		hdev = hci_dev_hold(hdev);
649 
650 	read_unlock(&hci_dev_list_lock);
651 	return hdev;
652 }
653 EXPORT_SYMBOL(hci_get_route);
654 
655 /* This function requires the caller holds hdev->lock */
656 void hci_le_conn_failed(struct hci_conn *conn, u8 status)
657 {
658 	struct hci_dev *hdev = conn->hdev;
659 	struct hci_conn_params *params;
660 
661 	params = hci_pend_le_action_lookup(&hdev->pend_le_conns, &conn->dst,
662 					   conn->dst_type);
663 	if (params && params->conn) {
664 		hci_conn_drop(params->conn);
665 		hci_conn_put(params->conn);
666 		params->conn = NULL;
667 	}
668 
669 	conn->state = BT_CLOSED;
670 
671 	/* If the status indicates successful cancellation of
672 	 * the attempt (i.e. Unkown Connection Id) there's no point of
673 	 * notifying failure since we'll go back to keep trying to
674 	 * connect. The only exception is explicit connect requests
675 	 * where a timeout + cancel does indicate an actual failure.
676 	 */
677 	if (status != HCI_ERROR_UNKNOWN_CONN_ID ||
678 	    (params && params->explicit_connect))
679 		mgmt_connect_failed(hdev, &conn->dst, conn->type,
680 				    conn->dst_type, status);
681 
682 	hci_connect_cfm(conn, status);
683 
684 	hci_conn_del(conn);
685 
686 	/* Since we may have temporarily stopped the background scanning in
687 	 * favor of connection establishment, we should restart it.
688 	 */
689 	hci_update_background_scan(hdev);
690 
691 	/* Re-enable advertising in case this was a failed connection
692 	 * attempt as a peripheral.
693 	 */
694 	hci_req_reenable_advertising(hdev);
695 }
696 
697 static void create_le_conn_complete(struct hci_dev *hdev, u8 status, u16 opcode)
698 {
699 	struct hci_conn *conn;
700 
701 	hci_dev_lock(hdev);
702 
703 	conn = hci_lookup_le_connect(hdev);
704 
705 	if (!status) {
706 		hci_connect_le_scan_cleanup(conn);
707 		goto done;
708 	}
709 
710 	BT_ERR("HCI request failed to create LE connection: status 0x%2.2x",
711 	       status);
712 
713 	if (!conn)
714 		goto done;
715 
716 	hci_le_conn_failed(conn, status);
717 
718 done:
719 	hci_dev_unlock(hdev);
720 }
721 
722 static void hci_req_add_le_create_conn(struct hci_request *req,
723 				       struct hci_conn *conn)
724 {
725 	struct hci_cp_le_create_conn cp;
726 	struct hci_dev *hdev = conn->hdev;
727 	u8 own_addr_type;
728 
729 	memset(&cp, 0, sizeof(cp));
730 
731 	/* Update random address, but set require_privacy to false so
732 	 * that we never connect with an non-resolvable address.
733 	 */
734 	if (hci_update_random_address(req, false, &own_addr_type))
735 		return;
736 
737 	/* Set window to be the same value as the interval to enable
738 	 * continuous scanning.
739 	 */
740 	cp.scan_interval = cpu_to_le16(hdev->le_scan_interval);
741 	cp.scan_window = cp.scan_interval;
742 
743 	bacpy(&cp.peer_addr, &conn->dst);
744 	cp.peer_addr_type = conn->dst_type;
745 	cp.own_address_type = own_addr_type;
746 	cp.conn_interval_min = cpu_to_le16(conn->le_conn_min_interval);
747 	cp.conn_interval_max = cpu_to_le16(conn->le_conn_max_interval);
748 	cp.conn_latency = cpu_to_le16(conn->le_conn_latency);
749 	cp.supervision_timeout = cpu_to_le16(conn->le_supv_timeout);
750 	cp.min_ce_len = cpu_to_le16(0x0000);
751 	cp.max_ce_len = cpu_to_le16(0x0000);
752 
753 	hci_req_add(req, HCI_OP_LE_CREATE_CONN, sizeof(cp), &cp);
754 
755 	conn->state = BT_CONNECT;
756 	clear_bit(HCI_CONN_SCANNING, &conn->flags);
757 }
758 
759 static void hci_req_directed_advertising(struct hci_request *req,
760 					 struct hci_conn *conn)
761 {
762 	struct hci_dev *hdev = req->hdev;
763 	struct hci_cp_le_set_adv_param cp;
764 	u8 own_addr_type;
765 	u8 enable;
766 
767 	/* Clear the HCI_LE_ADV bit temporarily so that the
768 	 * hci_update_random_address knows that it's safe to go ahead
769 	 * and write a new random address. The flag will be set back on
770 	 * as soon as the SET_ADV_ENABLE HCI command completes.
771 	 */
772 	hci_dev_clear_flag(hdev, HCI_LE_ADV);
773 
774 	/* Set require_privacy to false so that the remote device has a
775 	 * chance of identifying us.
776 	 */
777 	if (hci_update_random_address(req, false, &own_addr_type) < 0)
778 		return;
779 
780 	memset(&cp, 0, sizeof(cp));
781 	cp.type = LE_ADV_DIRECT_IND;
782 	cp.own_address_type = own_addr_type;
783 	cp.direct_addr_type = conn->dst_type;
784 	bacpy(&cp.direct_addr, &conn->dst);
785 	cp.channel_map = hdev->le_adv_channel_map;
786 
787 	hci_req_add(req, HCI_OP_LE_SET_ADV_PARAM, sizeof(cp), &cp);
788 
789 	enable = 0x01;
790 	hci_req_add(req, HCI_OP_LE_SET_ADV_ENABLE, sizeof(enable), &enable);
791 
792 	conn->state = BT_CONNECT;
793 }
794 
795 struct hci_conn *hci_connect_le(struct hci_dev *hdev, bdaddr_t *dst,
796 				u8 dst_type, u8 sec_level, u16 conn_timeout,
797 				u8 role)
798 {
799 	struct hci_conn_params *params;
800 	struct hci_conn *conn;
801 	struct smp_irk *irk;
802 	struct hci_request req;
803 	int err;
804 
805 	/* Let's make sure that le is enabled.*/
806 	if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED)) {
807 		if (lmp_le_capable(hdev))
808 			return ERR_PTR(-ECONNREFUSED);
809 
810 		return ERR_PTR(-EOPNOTSUPP);
811 	}
812 
813 	/* Since the controller supports only one LE connection attempt at a
814 	 * time, we return -EBUSY if there is any connection attempt running.
815 	 */
816 	if (hci_lookup_le_connect(hdev))
817 		return ERR_PTR(-EBUSY);
818 
819 	/* If there's already a connection object but it's not in
820 	 * scanning state it means it must already be established, in
821 	 * which case we can't do anything else except report a failure
822 	 * to connect.
823 	 */
824 	conn = hci_conn_hash_lookup_le(hdev, dst, dst_type);
825 	if (conn && !test_bit(HCI_CONN_SCANNING, &conn->flags)) {
826 		return ERR_PTR(-EBUSY);
827 	}
828 
829 	/* When given an identity address with existing identity
830 	 * resolving key, the connection needs to be established
831 	 * to a resolvable random address.
832 	 *
833 	 * Storing the resolvable random address is required here
834 	 * to handle connection failures. The address will later
835 	 * be resolved back into the original identity address
836 	 * from the connect request.
837 	 */
838 	irk = hci_find_irk_by_addr(hdev, dst, dst_type);
839 	if (irk && bacmp(&irk->rpa, BDADDR_ANY)) {
840 		dst = &irk->rpa;
841 		dst_type = ADDR_LE_DEV_RANDOM;
842 	}
843 
844 	if (conn) {
845 		bacpy(&conn->dst, dst);
846 	} else {
847 		conn = hci_conn_add(hdev, LE_LINK, dst, role);
848 		if (!conn)
849 			return ERR_PTR(-ENOMEM);
850 		hci_conn_hold(conn);
851 		conn->pending_sec_level = sec_level;
852 	}
853 
854 	conn->dst_type = dst_type;
855 	conn->sec_level = BT_SECURITY_LOW;
856 	conn->conn_timeout = conn_timeout;
857 
858 	hci_req_init(&req, hdev);
859 
860 	/* Disable advertising if we're active. For master role
861 	 * connections most controllers will refuse to connect if
862 	 * advertising is enabled, and for slave role connections we
863 	 * anyway have to disable it in order to start directed
864 	 * advertising.
865 	 */
866 	if (hci_dev_test_flag(hdev, HCI_LE_ADV)) {
867 		u8 enable = 0x00;
868 		hci_req_add(&req, HCI_OP_LE_SET_ADV_ENABLE, sizeof(enable),
869 			    &enable);
870 	}
871 
872 	/* If requested to connect as slave use directed advertising */
873 	if (conn->role == HCI_ROLE_SLAVE) {
874 		/* If we're active scanning most controllers are unable
875 		 * to initiate advertising. Simply reject the attempt.
876 		 */
877 		if (hci_dev_test_flag(hdev, HCI_LE_SCAN) &&
878 		    hdev->le_scan_type == LE_SCAN_ACTIVE) {
879 			skb_queue_purge(&req.cmd_q);
880 			hci_conn_del(conn);
881 			return ERR_PTR(-EBUSY);
882 		}
883 
884 		hci_req_directed_advertising(&req, conn);
885 		goto create_conn;
886 	}
887 
888 	params = hci_conn_params_lookup(hdev, &conn->dst, conn->dst_type);
889 	if (params) {
890 		conn->le_conn_min_interval = params->conn_min_interval;
891 		conn->le_conn_max_interval = params->conn_max_interval;
892 		conn->le_conn_latency = params->conn_latency;
893 		conn->le_supv_timeout = params->supervision_timeout;
894 	} else {
895 		conn->le_conn_min_interval = hdev->le_conn_min_interval;
896 		conn->le_conn_max_interval = hdev->le_conn_max_interval;
897 		conn->le_conn_latency = hdev->le_conn_latency;
898 		conn->le_supv_timeout = hdev->le_supv_timeout;
899 	}
900 
901 	/* If controller is scanning, we stop it since some controllers are
902 	 * not able to scan and connect at the same time. Also set the
903 	 * HCI_LE_SCAN_INTERRUPTED flag so that the command complete
904 	 * handler for scan disabling knows to set the correct discovery
905 	 * state.
906 	 */
907 	if (hci_dev_test_flag(hdev, HCI_LE_SCAN)) {
908 		hci_req_add_le_scan_disable(&req);
909 		hci_dev_set_flag(hdev, HCI_LE_SCAN_INTERRUPTED);
910 	}
911 
912 	hci_req_add_le_create_conn(&req, conn);
913 
914 create_conn:
915 	err = hci_req_run(&req, create_le_conn_complete);
916 	if (err) {
917 		hci_conn_del(conn);
918 		return ERR_PTR(err);
919 	}
920 
921 	return conn;
922 }
923 
924 static bool is_connected(struct hci_dev *hdev, bdaddr_t *addr, u8 type)
925 {
926 	struct hci_conn *conn;
927 
928 	conn = hci_conn_hash_lookup_le(hdev, addr, type);
929 	if (!conn)
930 		return false;
931 
932 	if (conn->state != BT_CONNECTED)
933 		return false;
934 
935 	return true;
936 }
937 
938 /* This function requires the caller holds hdev->lock */
939 static int hci_explicit_conn_params_set(struct hci_dev *hdev,
940 					bdaddr_t *addr, u8 addr_type)
941 {
942 	struct hci_conn_params *params;
943 
944 	if (is_connected(hdev, addr, addr_type))
945 		return -EISCONN;
946 
947 	params = hci_conn_params_lookup(hdev, addr, addr_type);
948 	if (!params) {
949 		params = hci_conn_params_add(hdev, addr, addr_type);
950 		if (!params)
951 			return -ENOMEM;
952 
953 		/* If we created new params, mark them to be deleted in
954 		 * hci_connect_le_scan_cleanup. It's different case than
955 		 * existing disabled params, those will stay after cleanup.
956 		 */
957 		params->auto_connect = HCI_AUTO_CONN_EXPLICIT;
958 	}
959 
960 	/* We're trying to connect, so make sure params are at pend_le_conns */
961 	if (params->auto_connect == HCI_AUTO_CONN_DISABLED ||
962 	    params->auto_connect == HCI_AUTO_CONN_REPORT ||
963 	    params->auto_connect == HCI_AUTO_CONN_EXPLICIT) {
964 		list_del_init(&params->action);
965 		list_add(&params->action, &hdev->pend_le_conns);
966 	}
967 
968 	params->explicit_connect = true;
969 
970 	BT_DBG("addr %pMR (type %u) auto_connect %u", addr, addr_type,
971 	       params->auto_connect);
972 
973 	return 0;
974 }
975 
976 /* This function requires the caller holds hdev->lock */
977 struct hci_conn *hci_connect_le_scan(struct hci_dev *hdev, bdaddr_t *dst,
978 				     u8 dst_type, u8 sec_level,
979 				     u16 conn_timeout)
980 {
981 	struct hci_conn *conn;
982 
983 	/* Let's make sure that le is enabled.*/
984 	if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED)) {
985 		if (lmp_le_capable(hdev))
986 			return ERR_PTR(-ECONNREFUSED);
987 
988 		return ERR_PTR(-EOPNOTSUPP);
989 	}
990 
991 	/* Some devices send ATT messages as soon as the physical link is
992 	 * established. To be able to handle these ATT messages, the user-
993 	 * space first establishes the connection and then starts the pairing
994 	 * process.
995 	 *
996 	 * So if a hci_conn object already exists for the following connection
997 	 * attempt, we simply update pending_sec_level and auth_type fields
998 	 * and return the object found.
999 	 */
1000 	conn = hci_conn_hash_lookup_le(hdev, dst, dst_type);
1001 	if (conn) {
1002 		if (conn->pending_sec_level < sec_level)
1003 			conn->pending_sec_level = sec_level;
1004 		goto done;
1005 	}
1006 
1007 	BT_DBG("requesting refresh of dst_addr");
1008 
1009 	conn = hci_conn_add(hdev, LE_LINK, dst, HCI_ROLE_MASTER);
1010 	if (!conn)
1011 		return ERR_PTR(-ENOMEM);
1012 
1013 	if (hci_explicit_conn_params_set(hdev, dst, dst_type) < 0)
1014 		return ERR_PTR(-EBUSY);
1015 
1016 	conn->state = BT_CONNECT;
1017 	set_bit(HCI_CONN_SCANNING, &conn->flags);
1018 	conn->dst_type = dst_type;
1019 	conn->sec_level = BT_SECURITY_LOW;
1020 	conn->pending_sec_level = sec_level;
1021 	conn->conn_timeout = conn_timeout;
1022 
1023 	hci_update_background_scan(hdev);
1024 
1025 done:
1026 	hci_conn_hold(conn);
1027 	return conn;
1028 }
1029 
1030 struct hci_conn *hci_connect_acl(struct hci_dev *hdev, bdaddr_t *dst,
1031 				 u8 sec_level, u8 auth_type)
1032 {
1033 	struct hci_conn *acl;
1034 
1035 	if (!hci_dev_test_flag(hdev, HCI_BREDR_ENABLED)) {
1036 		if (lmp_bredr_capable(hdev))
1037 			return ERR_PTR(-ECONNREFUSED);
1038 
1039 		return ERR_PTR(-EOPNOTSUPP);
1040 	}
1041 
1042 	acl = hci_conn_hash_lookup_ba(hdev, ACL_LINK, dst);
1043 	if (!acl) {
1044 		acl = hci_conn_add(hdev, ACL_LINK, dst, HCI_ROLE_MASTER);
1045 		if (!acl)
1046 			return ERR_PTR(-ENOMEM);
1047 	}
1048 
1049 	hci_conn_hold(acl);
1050 
1051 	if (acl->state == BT_OPEN || acl->state == BT_CLOSED) {
1052 		acl->sec_level = BT_SECURITY_LOW;
1053 		acl->pending_sec_level = sec_level;
1054 		acl->auth_type = auth_type;
1055 		hci_acl_create_connection(acl);
1056 	}
1057 
1058 	return acl;
1059 }
1060 
1061 struct hci_conn *hci_connect_sco(struct hci_dev *hdev, int type, bdaddr_t *dst,
1062 				 __u16 setting)
1063 {
1064 	struct hci_conn *acl;
1065 	struct hci_conn *sco;
1066 
1067 	acl = hci_connect_acl(hdev, dst, BT_SECURITY_LOW, HCI_AT_NO_BONDING);
1068 	if (IS_ERR(acl))
1069 		return acl;
1070 
1071 	sco = hci_conn_hash_lookup_ba(hdev, type, dst);
1072 	if (!sco) {
1073 		sco = hci_conn_add(hdev, type, dst, HCI_ROLE_MASTER);
1074 		if (!sco) {
1075 			hci_conn_drop(acl);
1076 			return ERR_PTR(-ENOMEM);
1077 		}
1078 	}
1079 
1080 	acl->link = sco;
1081 	sco->link = acl;
1082 
1083 	hci_conn_hold(sco);
1084 
1085 	sco->setting = setting;
1086 
1087 	if (acl->state == BT_CONNECTED &&
1088 	    (sco->state == BT_OPEN || sco->state == BT_CLOSED)) {
1089 		set_bit(HCI_CONN_POWER_SAVE, &acl->flags);
1090 		hci_conn_enter_active_mode(acl, BT_POWER_FORCE_ACTIVE_ON);
1091 
1092 		if (test_bit(HCI_CONN_MODE_CHANGE_PEND, &acl->flags)) {
1093 			/* defer SCO setup until mode change completed */
1094 			set_bit(HCI_CONN_SCO_SETUP_PEND, &acl->flags);
1095 			return sco;
1096 		}
1097 
1098 		hci_sco_setup(acl, 0x00);
1099 	}
1100 
1101 	return sco;
1102 }
1103 
1104 /* Check link security requirement */
1105 int hci_conn_check_link_mode(struct hci_conn *conn)
1106 {
1107 	BT_DBG("hcon %p", conn);
1108 
1109 	/* In Secure Connections Only mode, it is required that Secure
1110 	 * Connections is used and the link is encrypted with AES-CCM
1111 	 * using a P-256 authenticated combination key.
1112 	 */
1113 	if (hci_dev_test_flag(conn->hdev, HCI_SC_ONLY)) {
1114 		if (!hci_conn_sc_enabled(conn) ||
1115 		    !test_bit(HCI_CONN_AES_CCM, &conn->flags) ||
1116 		    conn->key_type != HCI_LK_AUTH_COMBINATION_P256)
1117 			return 0;
1118 	}
1119 
1120 	if (hci_conn_ssp_enabled(conn) &&
1121 	    !test_bit(HCI_CONN_ENCRYPT, &conn->flags))
1122 		return 0;
1123 
1124 	return 1;
1125 }
1126 
1127 /* Authenticate remote device */
1128 static int hci_conn_auth(struct hci_conn *conn, __u8 sec_level, __u8 auth_type)
1129 {
1130 	BT_DBG("hcon %p", conn);
1131 
1132 	if (conn->pending_sec_level > sec_level)
1133 		sec_level = conn->pending_sec_level;
1134 
1135 	if (sec_level > conn->sec_level)
1136 		conn->pending_sec_level = sec_level;
1137 	else if (test_bit(HCI_CONN_AUTH, &conn->flags))
1138 		return 1;
1139 
1140 	/* Make sure we preserve an existing MITM requirement*/
1141 	auth_type |= (conn->auth_type & 0x01);
1142 
1143 	conn->auth_type = auth_type;
1144 
1145 	if (!test_and_set_bit(HCI_CONN_AUTH_PEND, &conn->flags)) {
1146 		struct hci_cp_auth_requested cp;
1147 
1148 		cp.handle = cpu_to_le16(conn->handle);
1149 		hci_send_cmd(conn->hdev, HCI_OP_AUTH_REQUESTED,
1150 			     sizeof(cp), &cp);
1151 
1152 		/* If we're already encrypted set the REAUTH_PEND flag,
1153 		 * otherwise set the ENCRYPT_PEND.
1154 		 */
1155 		if (test_bit(HCI_CONN_ENCRYPT, &conn->flags))
1156 			set_bit(HCI_CONN_REAUTH_PEND, &conn->flags);
1157 		else
1158 			set_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags);
1159 	}
1160 
1161 	return 0;
1162 }
1163 
1164 /* Encrypt the the link */
1165 static void hci_conn_encrypt(struct hci_conn *conn)
1166 {
1167 	BT_DBG("hcon %p", conn);
1168 
1169 	if (!test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags)) {
1170 		struct hci_cp_set_conn_encrypt cp;
1171 		cp.handle  = cpu_to_le16(conn->handle);
1172 		cp.encrypt = 0x01;
1173 		hci_send_cmd(conn->hdev, HCI_OP_SET_CONN_ENCRYPT, sizeof(cp),
1174 			     &cp);
1175 	}
1176 }
1177 
1178 /* Enable security */
1179 int hci_conn_security(struct hci_conn *conn, __u8 sec_level, __u8 auth_type,
1180 		      bool initiator)
1181 {
1182 	BT_DBG("hcon %p", conn);
1183 
1184 	if (conn->type == LE_LINK)
1185 		return smp_conn_security(conn, sec_level);
1186 
1187 	/* For sdp we don't need the link key. */
1188 	if (sec_level == BT_SECURITY_SDP)
1189 		return 1;
1190 
1191 	/* For non 2.1 devices and low security level we don't need the link
1192 	   key. */
1193 	if (sec_level == BT_SECURITY_LOW && !hci_conn_ssp_enabled(conn))
1194 		return 1;
1195 
1196 	/* For other security levels we need the link key. */
1197 	if (!test_bit(HCI_CONN_AUTH, &conn->flags))
1198 		goto auth;
1199 
1200 	/* An authenticated FIPS approved combination key has sufficient
1201 	 * security for security level 4. */
1202 	if (conn->key_type == HCI_LK_AUTH_COMBINATION_P256 &&
1203 	    sec_level == BT_SECURITY_FIPS)
1204 		goto encrypt;
1205 
1206 	/* An authenticated combination key has sufficient security for
1207 	   security level 3. */
1208 	if ((conn->key_type == HCI_LK_AUTH_COMBINATION_P192 ||
1209 	     conn->key_type == HCI_LK_AUTH_COMBINATION_P256) &&
1210 	    sec_level == BT_SECURITY_HIGH)
1211 		goto encrypt;
1212 
1213 	/* An unauthenticated combination key has sufficient security for
1214 	   security level 1 and 2. */
1215 	if ((conn->key_type == HCI_LK_UNAUTH_COMBINATION_P192 ||
1216 	     conn->key_type == HCI_LK_UNAUTH_COMBINATION_P256) &&
1217 	    (sec_level == BT_SECURITY_MEDIUM || sec_level == BT_SECURITY_LOW))
1218 		goto encrypt;
1219 
1220 	/* A combination key has always sufficient security for the security
1221 	   levels 1 or 2. High security level requires the combination key
1222 	   is generated using maximum PIN code length (16).
1223 	   For pre 2.1 units. */
1224 	if (conn->key_type == HCI_LK_COMBINATION &&
1225 	    (sec_level == BT_SECURITY_MEDIUM || sec_level == BT_SECURITY_LOW ||
1226 	     conn->pin_length == 16))
1227 		goto encrypt;
1228 
1229 auth:
1230 	if (test_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags))
1231 		return 0;
1232 
1233 	if (initiator)
1234 		set_bit(HCI_CONN_AUTH_INITIATOR, &conn->flags);
1235 
1236 	if (!hci_conn_auth(conn, sec_level, auth_type))
1237 		return 0;
1238 
1239 encrypt:
1240 	if (test_bit(HCI_CONN_ENCRYPT, &conn->flags))
1241 		return 1;
1242 
1243 	hci_conn_encrypt(conn);
1244 	return 0;
1245 }
1246 EXPORT_SYMBOL(hci_conn_security);
1247 
1248 /* Check secure link requirement */
1249 int hci_conn_check_secure(struct hci_conn *conn, __u8 sec_level)
1250 {
1251 	BT_DBG("hcon %p", conn);
1252 
1253 	/* Accept if non-secure or higher security level is required */
1254 	if (sec_level != BT_SECURITY_HIGH && sec_level != BT_SECURITY_FIPS)
1255 		return 1;
1256 
1257 	/* Accept if secure or higher security level is already present */
1258 	if (conn->sec_level == BT_SECURITY_HIGH ||
1259 	    conn->sec_level == BT_SECURITY_FIPS)
1260 		return 1;
1261 
1262 	/* Reject not secure link */
1263 	return 0;
1264 }
1265 EXPORT_SYMBOL(hci_conn_check_secure);
1266 
1267 /* Switch role */
1268 int hci_conn_switch_role(struct hci_conn *conn, __u8 role)
1269 {
1270 	BT_DBG("hcon %p", conn);
1271 
1272 	if (role == conn->role)
1273 		return 1;
1274 
1275 	if (!test_and_set_bit(HCI_CONN_RSWITCH_PEND, &conn->flags)) {
1276 		struct hci_cp_switch_role cp;
1277 		bacpy(&cp.bdaddr, &conn->dst);
1278 		cp.role = role;
1279 		hci_send_cmd(conn->hdev, HCI_OP_SWITCH_ROLE, sizeof(cp), &cp);
1280 	}
1281 
1282 	return 0;
1283 }
1284 EXPORT_SYMBOL(hci_conn_switch_role);
1285 
1286 /* Enter active mode */
1287 void hci_conn_enter_active_mode(struct hci_conn *conn, __u8 force_active)
1288 {
1289 	struct hci_dev *hdev = conn->hdev;
1290 
1291 	BT_DBG("hcon %p mode %d", conn, conn->mode);
1292 
1293 	if (conn->mode != HCI_CM_SNIFF)
1294 		goto timer;
1295 
1296 	if (!test_bit(HCI_CONN_POWER_SAVE, &conn->flags) && !force_active)
1297 		goto timer;
1298 
1299 	if (!test_and_set_bit(HCI_CONN_MODE_CHANGE_PEND, &conn->flags)) {
1300 		struct hci_cp_exit_sniff_mode cp;
1301 		cp.handle = cpu_to_le16(conn->handle);
1302 		hci_send_cmd(hdev, HCI_OP_EXIT_SNIFF_MODE, sizeof(cp), &cp);
1303 	}
1304 
1305 timer:
1306 	if (hdev->idle_timeout > 0)
1307 		queue_delayed_work(hdev->workqueue, &conn->idle_work,
1308 				   msecs_to_jiffies(hdev->idle_timeout));
1309 }
1310 
1311 /* Drop all connection on the device */
1312 void hci_conn_hash_flush(struct hci_dev *hdev)
1313 {
1314 	struct hci_conn_hash *h = &hdev->conn_hash;
1315 	struct hci_conn *c, *n;
1316 
1317 	BT_DBG("hdev %s", hdev->name);
1318 
1319 	list_for_each_entry_safe(c, n, &h->list, list) {
1320 		c->state = BT_CLOSED;
1321 
1322 		hci_disconn_cfm(c, HCI_ERROR_LOCAL_HOST_TERM);
1323 		hci_conn_del(c);
1324 	}
1325 }
1326 
1327 /* Check pending connect attempts */
1328 void hci_conn_check_pending(struct hci_dev *hdev)
1329 {
1330 	struct hci_conn *conn;
1331 
1332 	BT_DBG("hdev %s", hdev->name);
1333 
1334 	hci_dev_lock(hdev);
1335 
1336 	conn = hci_conn_hash_lookup_state(hdev, ACL_LINK, BT_CONNECT2);
1337 	if (conn)
1338 		hci_acl_create_connection(conn);
1339 
1340 	hci_dev_unlock(hdev);
1341 }
1342 
1343 static u32 get_link_mode(struct hci_conn *conn)
1344 {
1345 	u32 link_mode = 0;
1346 
1347 	if (conn->role == HCI_ROLE_MASTER)
1348 		link_mode |= HCI_LM_MASTER;
1349 
1350 	if (test_bit(HCI_CONN_ENCRYPT, &conn->flags))
1351 		link_mode |= HCI_LM_ENCRYPT;
1352 
1353 	if (test_bit(HCI_CONN_AUTH, &conn->flags))
1354 		link_mode |= HCI_LM_AUTH;
1355 
1356 	if (test_bit(HCI_CONN_SECURE, &conn->flags))
1357 		link_mode |= HCI_LM_SECURE;
1358 
1359 	if (test_bit(HCI_CONN_FIPS, &conn->flags))
1360 		link_mode |= HCI_LM_FIPS;
1361 
1362 	return link_mode;
1363 }
1364 
1365 int hci_get_conn_list(void __user *arg)
1366 {
1367 	struct hci_conn *c;
1368 	struct hci_conn_list_req req, *cl;
1369 	struct hci_conn_info *ci;
1370 	struct hci_dev *hdev;
1371 	int n = 0, size, err;
1372 
1373 	if (copy_from_user(&req, arg, sizeof(req)))
1374 		return -EFAULT;
1375 
1376 	if (!req.conn_num || req.conn_num > (PAGE_SIZE * 2) / sizeof(*ci))
1377 		return -EINVAL;
1378 
1379 	size = sizeof(req) + req.conn_num * sizeof(*ci);
1380 
1381 	cl = kmalloc(size, GFP_KERNEL);
1382 	if (!cl)
1383 		return -ENOMEM;
1384 
1385 	hdev = hci_dev_get(req.dev_id);
1386 	if (!hdev) {
1387 		kfree(cl);
1388 		return -ENODEV;
1389 	}
1390 
1391 	ci = cl->conn_info;
1392 
1393 	hci_dev_lock(hdev);
1394 	list_for_each_entry(c, &hdev->conn_hash.list, list) {
1395 		bacpy(&(ci + n)->bdaddr, &c->dst);
1396 		(ci + n)->handle = c->handle;
1397 		(ci + n)->type  = c->type;
1398 		(ci + n)->out   = c->out;
1399 		(ci + n)->state = c->state;
1400 		(ci + n)->link_mode = get_link_mode(c);
1401 		if (++n >= req.conn_num)
1402 			break;
1403 	}
1404 	hci_dev_unlock(hdev);
1405 
1406 	cl->dev_id = hdev->id;
1407 	cl->conn_num = n;
1408 	size = sizeof(req) + n * sizeof(*ci);
1409 
1410 	hci_dev_put(hdev);
1411 
1412 	err = copy_to_user(arg, cl, size);
1413 	kfree(cl);
1414 
1415 	return err ? -EFAULT : 0;
1416 }
1417 
1418 int hci_get_conn_info(struct hci_dev *hdev, void __user *arg)
1419 {
1420 	struct hci_conn_info_req req;
1421 	struct hci_conn_info ci;
1422 	struct hci_conn *conn;
1423 	char __user *ptr = arg + sizeof(req);
1424 
1425 	if (copy_from_user(&req, arg, sizeof(req)))
1426 		return -EFAULT;
1427 
1428 	hci_dev_lock(hdev);
1429 	conn = hci_conn_hash_lookup_ba(hdev, req.type, &req.bdaddr);
1430 	if (conn) {
1431 		bacpy(&ci.bdaddr, &conn->dst);
1432 		ci.handle = conn->handle;
1433 		ci.type  = conn->type;
1434 		ci.out   = conn->out;
1435 		ci.state = conn->state;
1436 		ci.link_mode = get_link_mode(conn);
1437 	}
1438 	hci_dev_unlock(hdev);
1439 
1440 	if (!conn)
1441 		return -ENOENT;
1442 
1443 	return copy_to_user(ptr, &ci, sizeof(ci)) ? -EFAULT : 0;
1444 }
1445 
1446 int hci_get_auth_info(struct hci_dev *hdev, void __user *arg)
1447 {
1448 	struct hci_auth_info_req req;
1449 	struct hci_conn *conn;
1450 
1451 	if (copy_from_user(&req, arg, sizeof(req)))
1452 		return -EFAULT;
1453 
1454 	hci_dev_lock(hdev);
1455 	conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, &req.bdaddr);
1456 	if (conn)
1457 		req.type = conn->auth_type;
1458 	hci_dev_unlock(hdev);
1459 
1460 	if (!conn)
1461 		return -ENOENT;
1462 
1463 	return copy_to_user(arg, &req, sizeof(req)) ? -EFAULT : 0;
1464 }
1465 
1466 struct hci_chan *hci_chan_create(struct hci_conn *conn)
1467 {
1468 	struct hci_dev *hdev = conn->hdev;
1469 	struct hci_chan *chan;
1470 
1471 	BT_DBG("%s hcon %p", hdev->name, conn);
1472 
1473 	if (test_bit(HCI_CONN_DROP, &conn->flags)) {
1474 		BT_DBG("Refusing to create new hci_chan");
1475 		return NULL;
1476 	}
1477 
1478 	chan = kzalloc(sizeof(*chan), GFP_KERNEL);
1479 	if (!chan)
1480 		return NULL;
1481 
1482 	chan->conn = hci_conn_get(conn);
1483 	skb_queue_head_init(&chan->data_q);
1484 	chan->state = BT_CONNECTED;
1485 
1486 	list_add_rcu(&chan->list, &conn->chan_list);
1487 
1488 	return chan;
1489 }
1490 
1491 void hci_chan_del(struct hci_chan *chan)
1492 {
1493 	struct hci_conn *conn = chan->conn;
1494 	struct hci_dev *hdev = conn->hdev;
1495 
1496 	BT_DBG("%s hcon %p chan %p", hdev->name, conn, chan);
1497 
1498 	list_del_rcu(&chan->list);
1499 
1500 	synchronize_rcu();
1501 
1502 	/* Prevent new hci_chan's to be created for this hci_conn */
1503 	set_bit(HCI_CONN_DROP, &conn->flags);
1504 
1505 	hci_conn_put(conn);
1506 
1507 	skb_queue_purge(&chan->data_q);
1508 	kfree(chan);
1509 }
1510 
1511 void hci_chan_list_flush(struct hci_conn *conn)
1512 {
1513 	struct hci_chan *chan, *n;
1514 
1515 	BT_DBG("hcon %p", conn);
1516 
1517 	list_for_each_entry_safe(chan, n, &conn->chan_list, list)
1518 		hci_chan_del(chan);
1519 }
1520 
1521 static struct hci_chan *__hci_chan_lookup_handle(struct hci_conn *hcon,
1522 						 __u16 handle)
1523 {
1524 	struct hci_chan *hchan;
1525 
1526 	list_for_each_entry(hchan, &hcon->chan_list, list) {
1527 		if (hchan->handle == handle)
1528 			return hchan;
1529 	}
1530 
1531 	return NULL;
1532 }
1533 
1534 struct hci_chan *hci_chan_lookup_handle(struct hci_dev *hdev, __u16 handle)
1535 {
1536 	struct hci_conn_hash *h = &hdev->conn_hash;
1537 	struct hci_conn *hcon;
1538 	struct hci_chan *hchan = NULL;
1539 
1540 	rcu_read_lock();
1541 
1542 	list_for_each_entry_rcu(hcon, &h->list, list) {
1543 		hchan = __hci_chan_lookup_handle(hcon, handle);
1544 		if (hchan)
1545 			break;
1546 	}
1547 
1548 	rcu_read_unlock();
1549 
1550 	return hchan;
1551 }
1552