xref: /openbmc/linux/net/bluetooth/hci_conn.c (revision 78700c0a)
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 bool conn_use_rpa(struct hci_conn *conn)
723 {
724 	struct hci_dev *hdev = conn->hdev;
725 
726 	return hci_dev_test_flag(hdev, HCI_PRIVACY);
727 }
728 
729 static void hci_req_add_le_create_conn(struct hci_request *req,
730 				       struct hci_conn *conn)
731 {
732 	struct hci_cp_le_create_conn cp;
733 	struct hci_dev *hdev = conn->hdev;
734 	u8 own_addr_type;
735 
736 	/* Update random address, but set require_privacy to false so
737 	 * that we never connect with an non-resolvable address.
738 	 */
739 	if (hci_update_random_address(req, false, conn_use_rpa(conn),
740 				      &own_addr_type))
741 		return;
742 
743 	memset(&cp, 0, sizeof(cp));
744 
745 	/* Set window to be the same value as the interval to enable
746 	 * continuous scanning.
747 	 */
748 	cp.scan_interval = cpu_to_le16(hdev->le_scan_interval);
749 	cp.scan_window = cp.scan_interval;
750 
751 	bacpy(&cp.peer_addr, &conn->dst);
752 	cp.peer_addr_type = conn->dst_type;
753 	cp.own_address_type = own_addr_type;
754 	cp.conn_interval_min = cpu_to_le16(conn->le_conn_min_interval);
755 	cp.conn_interval_max = cpu_to_le16(conn->le_conn_max_interval);
756 	cp.conn_latency = cpu_to_le16(conn->le_conn_latency);
757 	cp.supervision_timeout = cpu_to_le16(conn->le_supv_timeout);
758 	cp.min_ce_len = cpu_to_le16(0x0000);
759 	cp.max_ce_len = cpu_to_le16(0x0000);
760 
761 	hci_req_add(req, HCI_OP_LE_CREATE_CONN, sizeof(cp), &cp);
762 
763 	conn->state = BT_CONNECT;
764 	clear_bit(HCI_CONN_SCANNING, &conn->flags);
765 }
766 
767 static void hci_req_directed_advertising(struct hci_request *req,
768 					 struct hci_conn *conn)
769 {
770 	struct hci_dev *hdev = req->hdev;
771 	struct hci_cp_le_set_adv_param cp;
772 	u8 own_addr_type;
773 	u8 enable;
774 
775 	/* Clear the HCI_LE_ADV bit temporarily so that the
776 	 * hci_update_random_address knows that it's safe to go ahead
777 	 * and write a new random address. The flag will be set back on
778 	 * as soon as the SET_ADV_ENABLE HCI command completes.
779 	 */
780 	hci_dev_clear_flag(hdev, HCI_LE_ADV);
781 
782 	/* Set require_privacy to false so that the remote device has a
783 	 * chance of identifying us.
784 	 */
785 	if (hci_update_random_address(req, false, conn_use_rpa(conn),
786 				      &own_addr_type) < 0)
787 		return;
788 
789 	memset(&cp, 0, sizeof(cp));
790 	cp.type = LE_ADV_DIRECT_IND;
791 	cp.own_address_type = own_addr_type;
792 	cp.direct_addr_type = conn->dst_type;
793 	bacpy(&cp.direct_addr, &conn->dst);
794 	cp.channel_map = hdev->le_adv_channel_map;
795 
796 	hci_req_add(req, HCI_OP_LE_SET_ADV_PARAM, sizeof(cp), &cp);
797 
798 	enable = 0x01;
799 	hci_req_add(req, HCI_OP_LE_SET_ADV_ENABLE, sizeof(enable), &enable);
800 
801 	conn->state = BT_CONNECT;
802 }
803 
804 struct hci_conn *hci_connect_le(struct hci_dev *hdev, bdaddr_t *dst,
805 				u8 dst_type, u8 sec_level, u16 conn_timeout,
806 				u8 role)
807 {
808 	struct hci_conn_params *params;
809 	struct hci_conn *conn;
810 	struct smp_irk *irk;
811 	struct hci_request req;
812 	int err;
813 
814 	/* Let's make sure that le is enabled.*/
815 	if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED)) {
816 		if (lmp_le_capable(hdev))
817 			return ERR_PTR(-ECONNREFUSED);
818 
819 		return ERR_PTR(-EOPNOTSUPP);
820 	}
821 
822 	/* Since the controller supports only one LE connection attempt at a
823 	 * time, we return -EBUSY if there is any connection attempt running.
824 	 */
825 	if (hci_lookup_le_connect(hdev))
826 		return ERR_PTR(-EBUSY);
827 
828 	/* If there's already a connection object but it's not in
829 	 * scanning state it means it must already be established, in
830 	 * which case we can't do anything else except report a failure
831 	 * to connect.
832 	 */
833 	conn = hci_conn_hash_lookup_le(hdev, dst, dst_type);
834 	if (conn && !test_bit(HCI_CONN_SCANNING, &conn->flags)) {
835 		return ERR_PTR(-EBUSY);
836 	}
837 
838 	/* When given an identity address with existing identity
839 	 * resolving key, the connection needs to be established
840 	 * to a resolvable random address.
841 	 *
842 	 * Storing the resolvable random address is required here
843 	 * to handle connection failures. The address will later
844 	 * be resolved back into the original identity address
845 	 * from the connect request.
846 	 */
847 	irk = hci_find_irk_by_addr(hdev, dst, dst_type);
848 	if (irk && bacmp(&irk->rpa, BDADDR_ANY)) {
849 		dst = &irk->rpa;
850 		dst_type = ADDR_LE_DEV_RANDOM;
851 	}
852 
853 	if (conn) {
854 		bacpy(&conn->dst, dst);
855 	} else {
856 		conn = hci_conn_add(hdev, LE_LINK, dst, role);
857 		if (!conn)
858 			return ERR_PTR(-ENOMEM);
859 		hci_conn_hold(conn);
860 		conn->pending_sec_level = sec_level;
861 	}
862 
863 	conn->dst_type = dst_type;
864 	conn->sec_level = BT_SECURITY_LOW;
865 	conn->conn_timeout = conn_timeout;
866 
867 	hci_req_init(&req, hdev);
868 
869 	/* Disable advertising if we're active. For master role
870 	 * connections most controllers will refuse to connect if
871 	 * advertising is enabled, and for slave role connections we
872 	 * anyway have to disable it in order to start directed
873 	 * advertising.
874 	 */
875 	if (hci_dev_test_flag(hdev, HCI_LE_ADV)) {
876 		u8 enable = 0x00;
877 		hci_req_add(&req, HCI_OP_LE_SET_ADV_ENABLE, sizeof(enable),
878 			    &enable);
879 	}
880 
881 	/* If requested to connect as slave use directed advertising */
882 	if (conn->role == HCI_ROLE_SLAVE) {
883 		/* If we're active scanning most controllers are unable
884 		 * to initiate advertising. Simply reject the attempt.
885 		 */
886 		if (hci_dev_test_flag(hdev, HCI_LE_SCAN) &&
887 		    hdev->le_scan_type == LE_SCAN_ACTIVE) {
888 			skb_queue_purge(&req.cmd_q);
889 			hci_conn_del(conn);
890 			return ERR_PTR(-EBUSY);
891 		}
892 
893 		hci_req_directed_advertising(&req, conn);
894 		goto create_conn;
895 	}
896 
897 	params = hci_conn_params_lookup(hdev, &conn->dst, conn->dst_type);
898 	if (params) {
899 		conn->le_conn_min_interval = params->conn_min_interval;
900 		conn->le_conn_max_interval = params->conn_max_interval;
901 		conn->le_conn_latency = params->conn_latency;
902 		conn->le_supv_timeout = params->supervision_timeout;
903 	} else {
904 		conn->le_conn_min_interval = hdev->le_conn_min_interval;
905 		conn->le_conn_max_interval = hdev->le_conn_max_interval;
906 		conn->le_conn_latency = hdev->le_conn_latency;
907 		conn->le_supv_timeout = hdev->le_supv_timeout;
908 	}
909 
910 	/* If controller is scanning, we stop it since some controllers are
911 	 * not able to scan and connect at the same time. Also set the
912 	 * HCI_LE_SCAN_INTERRUPTED flag so that the command complete
913 	 * handler for scan disabling knows to set the correct discovery
914 	 * state.
915 	 */
916 	if (hci_dev_test_flag(hdev, HCI_LE_SCAN)) {
917 		hci_req_add_le_scan_disable(&req);
918 		hci_dev_set_flag(hdev, HCI_LE_SCAN_INTERRUPTED);
919 	}
920 
921 	hci_req_add_le_create_conn(&req, conn);
922 
923 create_conn:
924 	err = hci_req_run(&req, create_le_conn_complete);
925 	if (err) {
926 		hci_conn_del(conn);
927 		return ERR_PTR(err);
928 	}
929 
930 	return conn;
931 }
932 
933 static bool is_connected(struct hci_dev *hdev, bdaddr_t *addr, u8 type)
934 {
935 	struct hci_conn *conn;
936 
937 	conn = hci_conn_hash_lookup_le(hdev, addr, type);
938 	if (!conn)
939 		return false;
940 
941 	if (conn->state != BT_CONNECTED)
942 		return false;
943 
944 	return true;
945 }
946 
947 /* This function requires the caller holds hdev->lock */
948 static int hci_explicit_conn_params_set(struct hci_dev *hdev,
949 					bdaddr_t *addr, u8 addr_type)
950 {
951 	struct hci_conn_params *params;
952 
953 	if (is_connected(hdev, addr, addr_type))
954 		return -EISCONN;
955 
956 	params = hci_conn_params_lookup(hdev, addr, addr_type);
957 	if (!params) {
958 		params = hci_conn_params_add(hdev, addr, addr_type);
959 		if (!params)
960 			return -ENOMEM;
961 
962 		/* If we created new params, mark them to be deleted in
963 		 * hci_connect_le_scan_cleanup. It's different case than
964 		 * existing disabled params, those will stay after cleanup.
965 		 */
966 		params->auto_connect = HCI_AUTO_CONN_EXPLICIT;
967 	}
968 
969 	/* We're trying to connect, so make sure params are at pend_le_conns */
970 	if (params->auto_connect == HCI_AUTO_CONN_DISABLED ||
971 	    params->auto_connect == HCI_AUTO_CONN_REPORT ||
972 	    params->auto_connect == HCI_AUTO_CONN_EXPLICIT) {
973 		list_del_init(&params->action);
974 		list_add(&params->action, &hdev->pend_le_conns);
975 	}
976 
977 	params->explicit_connect = true;
978 
979 	BT_DBG("addr %pMR (type %u) auto_connect %u", addr, addr_type,
980 	       params->auto_connect);
981 
982 	return 0;
983 }
984 
985 /* This function requires the caller holds hdev->lock */
986 struct hci_conn *hci_connect_le_scan(struct hci_dev *hdev, bdaddr_t *dst,
987 				     u8 dst_type, u8 sec_level,
988 				     u16 conn_timeout)
989 {
990 	struct hci_conn *conn;
991 
992 	/* Let's make sure that le is enabled.*/
993 	if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED)) {
994 		if (lmp_le_capable(hdev))
995 			return ERR_PTR(-ECONNREFUSED);
996 
997 		return ERR_PTR(-EOPNOTSUPP);
998 	}
999 
1000 	/* Some devices send ATT messages as soon as the physical link is
1001 	 * established. To be able to handle these ATT messages, the user-
1002 	 * space first establishes the connection and then starts the pairing
1003 	 * process.
1004 	 *
1005 	 * So if a hci_conn object already exists for the following connection
1006 	 * attempt, we simply update pending_sec_level and auth_type fields
1007 	 * and return the object found.
1008 	 */
1009 	conn = hci_conn_hash_lookup_le(hdev, dst, dst_type);
1010 	if (conn) {
1011 		if (conn->pending_sec_level < sec_level)
1012 			conn->pending_sec_level = sec_level;
1013 		goto done;
1014 	}
1015 
1016 	BT_DBG("requesting refresh of dst_addr");
1017 
1018 	conn = hci_conn_add(hdev, LE_LINK, dst, HCI_ROLE_MASTER);
1019 	if (!conn)
1020 		return ERR_PTR(-ENOMEM);
1021 
1022 	if (hci_explicit_conn_params_set(hdev, dst, dst_type) < 0)
1023 		return ERR_PTR(-EBUSY);
1024 
1025 	conn->state = BT_CONNECT;
1026 	set_bit(HCI_CONN_SCANNING, &conn->flags);
1027 	conn->dst_type = dst_type;
1028 	conn->sec_level = BT_SECURITY_LOW;
1029 	conn->pending_sec_level = sec_level;
1030 	conn->conn_timeout = conn_timeout;
1031 
1032 	hci_update_background_scan(hdev);
1033 
1034 done:
1035 	hci_conn_hold(conn);
1036 	return conn;
1037 }
1038 
1039 struct hci_conn *hci_connect_acl(struct hci_dev *hdev, bdaddr_t *dst,
1040 				 u8 sec_level, u8 auth_type)
1041 {
1042 	struct hci_conn *acl;
1043 
1044 	if (!hci_dev_test_flag(hdev, HCI_BREDR_ENABLED)) {
1045 		if (lmp_bredr_capable(hdev))
1046 			return ERR_PTR(-ECONNREFUSED);
1047 
1048 		return ERR_PTR(-EOPNOTSUPP);
1049 	}
1050 
1051 	acl = hci_conn_hash_lookup_ba(hdev, ACL_LINK, dst);
1052 	if (!acl) {
1053 		acl = hci_conn_add(hdev, ACL_LINK, dst, HCI_ROLE_MASTER);
1054 		if (!acl)
1055 			return ERR_PTR(-ENOMEM);
1056 	}
1057 
1058 	hci_conn_hold(acl);
1059 
1060 	if (acl->state == BT_OPEN || acl->state == BT_CLOSED) {
1061 		acl->sec_level = BT_SECURITY_LOW;
1062 		acl->pending_sec_level = sec_level;
1063 		acl->auth_type = auth_type;
1064 		hci_acl_create_connection(acl);
1065 	}
1066 
1067 	return acl;
1068 }
1069 
1070 struct hci_conn *hci_connect_sco(struct hci_dev *hdev, int type, bdaddr_t *dst,
1071 				 __u16 setting)
1072 {
1073 	struct hci_conn *acl;
1074 	struct hci_conn *sco;
1075 
1076 	acl = hci_connect_acl(hdev, dst, BT_SECURITY_LOW, HCI_AT_NO_BONDING);
1077 	if (IS_ERR(acl))
1078 		return acl;
1079 
1080 	sco = hci_conn_hash_lookup_ba(hdev, type, dst);
1081 	if (!sco) {
1082 		sco = hci_conn_add(hdev, type, dst, HCI_ROLE_MASTER);
1083 		if (!sco) {
1084 			hci_conn_drop(acl);
1085 			return ERR_PTR(-ENOMEM);
1086 		}
1087 	}
1088 
1089 	acl->link = sco;
1090 	sco->link = acl;
1091 
1092 	hci_conn_hold(sco);
1093 
1094 	sco->setting = setting;
1095 
1096 	if (acl->state == BT_CONNECTED &&
1097 	    (sco->state == BT_OPEN || sco->state == BT_CLOSED)) {
1098 		set_bit(HCI_CONN_POWER_SAVE, &acl->flags);
1099 		hci_conn_enter_active_mode(acl, BT_POWER_FORCE_ACTIVE_ON);
1100 
1101 		if (test_bit(HCI_CONN_MODE_CHANGE_PEND, &acl->flags)) {
1102 			/* defer SCO setup until mode change completed */
1103 			set_bit(HCI_CONN_SCO_SETUP_PEND, &acl->flags);
1104 			return sco;
1105 		}
1106 
1107 		hci_sco_setup(acl, 0x00);
1108 	}
1109 
1110 	return sco;
1111 }
1112 
1113 /* Check link security requirement */
1114 int hci_conn_check_link_mode(struct hci_conn *conn)
1115 {
1116 	BT_DBG("hcon %p", conn);
1117 
1118 	/* In Secure Connections Only mode, it is required that Secure
1119 	 * Connections is used and the link is encrypted with AES-CCM
1120 	 * using a P-256 authenticated combination key.
1121 	 */
1122 	if (hci_dev_test_flag(conn->hdev, HCI_SC_ONLY)) {
1123 		if (!hci_conn_sc_enabled(conn) ||
1124 		    !test_bit(HCI_CONN_AES_CCM, &conn->flags) ||
1125 		    conn->key_type != HCI_LK_AUTH_COMBINATION_P256)
1126 			return 0;
1127 	}
1128 
1129 	if (hci_conn_ssp_enabled(conn) &&
1130 	    !test_bit(HCI_CONN_ENCRYPT, &conn->flags))
1131 		return 0;
1132 
1133 	return 1;
1134 }
1135 
1136 /* Authenticate remote device */
1137 static int hci_conn_auth(struct hci_conn *conn, __u8 sec_level, __u8 auth_type)
1138 {
1139 	BT_DBG("hcon %p", conn);
1140 
1141 	if (conn->pending_sec_level > sec_level)
1142 		sec_level = conn->pending_sec_level;
1143 
1144 	if (sec_level > conn->sec_level)
1145 		conn->pending_sec_level = sec_level;
1146 	else if (test_bit(HCI_CONN_AUTH, &conn->flags))
1147 		return 1;
1148 
1149 	/* Make sure we preserve an existing MITM requirement*/
1150 	auth_type |= (conn->auth_type & 0x01);
1151 
1152 	conn->auth_type = auth_type;
1153 
1154 	if (!test_and_set_bit(HCI_CONN_AUTH_PEND, &conn->flags)) {
1155 		struct hci_cp_auth_requested cp;
1156 
1157 		cp.handle = cpu_to_le16(conn->handle);
1158 		hci_send_cmd(conn->hdev, HCI_OP_AUTH_REQUESTED,
1159 			     sizeof(cp), &cp);
1160 
1161 		/* If we're already encrypted set the REAUTH_PEND flag,
1162 		 * otherwise set the ENCRYPT_PEND.
1163 		 */
1164 		if (test_bit(HCI_CONN_ENCRYPT, &conn->flags))
1165 			set_bit(HCI_CONN_REAUTH_PEND, &conn->flags);
1166 		else
1167 			set_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags);
1168 	}
1169 
1170 	return 0;
1171 }
1172 
1173 /* Encrypt the the link */
1174 static void hci_conn_encrypt(struct hci_conn *conn)
1175 {
1176 	BT_DBG("hcon %p", conn);
1177 
1178 	if (!test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags)) {
1179 		struct hci_cp_set_conn_encrypt cp;
1180 		cp.handle  = cpu_to_le16(conn->handle);
1181 		cp.encrypt = 0x01;
1182 		hci_send_cmd(conn->hdev, HCI_OP_SET_CONN_ENCRYPT, sizeof(cp),
1183 			     &cp);
1184 	}
1185 }
1186 
1187 /* Enable security */
1188 int hci_conn_security(struct hci_conn *conn, __u8 sec_level, __u8 auth_type,
1189 		      bool initiator)
1190 {
1191 	BT_DBG("hcon %p", conn);
1192 
1193 	if (conn->type == LE_LINK)
1194 		return smp_conn_security(conn, sec_level);
1195 
1196 	/* For sdp we don't need the link key. */
1197 	if (sec_level == BT_SECURITY_SDP)
1198 		return 1;
1199 
1200 	/* For non 2.1 devices and low security level we don't need the link
1201 	   key. */
1202 	if (sec_level == BT_SECURITY_LOW && !hci_conn_ssp_enabled(conn))
1203 		return 1;
1204 
1205 	/* For other security levels we need the link key. */
1206 	if (!test_bit(HCI_CONN_AUTH, &conn->flags))
1207 		goto auth;
1208 
1209 	/* An authenticated FIPS approved combination key has sufficient
1210 	 * security for security level 4. */
1211 	if (conn->key_type == HCI_LK_AUTH_COMBINATION_P256 &&
1212 	    sec_level == BT_SECURITY_FIPS)
1213 		goto encrypt;
1214 
1215 	/* An authenticated combination key has sufficient security for
1216 	   security level 3. */
1217 	if ((conn->key_type == HCI_LK_AUTH_COMBINATION_P192 ||
1218 	     conn->key_type == HCI_LK_AUTH_COMBINATION_P256) &&
1219 	    sec_level == BT_SECURITY_HIGH)
1220 		goto encrypt;
1221 
1222 	/* An unauthenticated combination key has sufficient security for
1223 	   security level 1 and 2. */
1224 	if ((conn->key_type == HCI_LK_UNAUTH_COMBINATION_P192 ||
1225 	     conn->key_type == HCI_LK_UNAUTH_COMBINATION_P256) &&
1226 	    (sec_level == BT_SECURITY_MEDIUM || sec_level == BT_SECURITY_LOW))
1227 		goto encrypt;
1228 
1229 	/* A combination key has always sufficient security for the security
1230 	   levels 1 or 2. High security level requires the combination key
1231 	   is generated using maximum PIN code length (16).
1232 	   For pre 2.1 units. */
1233 	if (conn->key_type == HCI_LK_COMBINATION &&
1234 	    (sec_level == BT_SECURITY_MEDIUM || sec_level == BT_SECURITY_LOW ||
1235 	     conn->pin_length == 16))
1236 		goto encrypt;
1237 
1238 auth:
1239 	if (test_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags))
1240 		return 0;
1241 
1242 	if (initiator)
1243 		set_bit(HCI_CONN_AUTH_INITIATOR, &conn->flags);
1244 
1245 	if (!hci_conn_auth(conn, sec_level, auth_type))
1246 		return 0;
1247 
1248 encrypt:
1249 	if (test_bit(HCI_CONN_ENCRYPT, &conn->flags))
1250 		return 1;
1251 
1252 	hci_conn_encrypt(conn);
1253 	return 0;
1254 }
1255 EXPORT_SYMBOL(hci_conn_security);
1256 
1257 /* Check secure link requirement */
1258 int hci_conn_check_secure(struct hci_conn *conn, __u8 sec_level)
1259 {
1260 	BT_DBG("hcon %p", conn);
1261 
1262 	/* Accept if non-secure or higher security level is required */
1263 	if (sec_level != BT_SECURITY_HIGH && sec_level != BT_SECURITY_FIPS)
1264 		return 1;
1265 
1266 	/* Accept if secure or higher security level is already present */
1267 	if (conn->sec_level == BT_SECURITY_HIGH ||
1268 	    conn->sec_level == BT_SECURITY_FIPS)
1269 		return 1;
1270 
1271 	/* Reject not secure link */
1272 	return 0;
1273 }
1274 EXPORT_SYMBOL(hci_conn_check_secure);
1275 
1276 /* Switch role */
1277 int hci_conn_switch_role(struct hci_conn *conn, __u8 role)
1278 {
1279 	BT_DBG("hcon %p", conn);
1280 
1281 	if (role == conn->role)
1282 		return 1;
1283 
1284 	if (!test_and_set_bit(HCI_CONN_RSWITCH_PEND, &conn->flags)) {
1285 		struct hci_cp_switch_role cp;
1286 		bacpy(&cp.bdaddr, &conn->dst);
1287 		cp.role = role;
1288 		hci_send_cmd(conn->hdev, HCI_OP_SWITCH_ROLE, sizeof(cp), &cp);
1289 	}
1290 
1291 	return 0;
1292 }
1293 EXPORT_SYMBOL(hci_conn_switch_role);
1294 
1295 /* Enter active mode */
1296 void hci_conn_enter_active_mode(struct hci_conn *conn, __u8 force_active)
1297 {
1298 	struct hci_dev *hdev = conn->hdev;
1299 
1300 	BT_DBG("hcon %p mode %d", conn, conn->mode);
1301 
1302 	if (conn->mode != HCI_CM_SNIFF)
1303 		goto timer;
1304 
1305 	if (!test_bit(HCI_CONN_POWER_SAVE, &conn->flags) && !force_active)
1306 		goto timer;
1307 
1308 	if (!test_and_set_bit(HCI_CONN_MODE_CHANGE_PEND, &conn->flags)) {
1309 		struct hci_cp_exit_sniff_mode cp;
1310 		cp.handle = cpu_to_le16(conn->handle);
1311 		hci_send_cmd(hdev, HCI_OP_EXIT_SNIFF_MODE, sizeof(cp), &cp);
1312 	}
1313 
1314 timer:
1315 	if (hdev->idle_timeout > 0)
1316 		queue_delayed_work(hdev->workqueue, &conn->idle_work,
1317 				   msecs_to_jiffies(hdev->idle_timeout));
1318 }
1319 
1320 /* Drop all connection on the device */
1321 void hci_conn_hash_flush(struct hci_dev *hdev)
1322 {
1323 	struct hci_conn_hash *h = &hdev->conn_hash;
1324 	struct hci_conn *c, *n;
1325 
1326 	BT_DBG("hdev %s", hdev->name);
1327 
1328 	list_for_each_entry_safe(c, n, &h->list, list) {
1329 		c->state = BT_CLOSED;
1330 
1331 		hci_disconn_cfm(c, HCI_ERROR_LOCAL_HOST_TERM);
1332 		hci_conn_del(c);
1333 	}
1334 }
1335 
1336 /* Check pending connect attempts */
1337 void hci_conn_check_pending(struct hci_dev *hdev)
1338 {
1339 	struct hci_conn *conn;
1340 
1341 	BT_DBG("hdev %s", hdev->name);
1342 
1343 	hci_dev_lock(hdev);
1344 
1345 	conn = hci_conn_hash_lookup_state(hdev, ACL_LINK, BT_CONNECT2);
1346 	if (conn)
1347 		hci_acl_create_connection(conn);
1348 
1349 	hci_dev_unlock(hdev);
1350 }
1351 
1352 static u32 get_link_mode(struct hci_conn *conn)
1353 {
1354 	u32 link_mode = 0;
1355 
1356 	if (conn->role == HCI_ROLE_MASTER)
1357 		link_mode |= HCI_LM_MASTER;
1358 
1359 	if (test_bit(HCI_CONN_ENCRYPT, &conn->flags))
1360 		link_mode |= HCI_LM_ENCRYPT;
1361 
1362 	if (test_bit(HCI_CONN_AUTH, &conn->flags))
1363 		link_mode |= HCI_LM_AUTH;
1364 
1365 	if (test_bit(HCI_CONN_SECURE, &conn->flags))
1366 		link_mode |= HCI_LM_SECURE;
1367 
1368 	if (test_bit(HCI_CONN_FIPS, &conn->flags))
1369 		link_mode |= HCI_LM_FIPS;
1370 
1371 	return link_mode;
1372 }
1373 
1374 int hci_get_conn_list(void __user *arg)
1375 {
1376 	struct hci_conn *c;
1377 	struct hci_conn_list_req req, *cl;
1378 	struct hci_conn_info *ci;
1379 	struct hci_dev *hdev;
1380 	int n = 0, size, err;
1381 
1382 	if (copy_from_user(&req, arg, sizeof(req)))
1383 		return -EFAULT;
1384 
1385 	if (!req.conn_num || req.conn_num > (PAGE_SIZE * 2) / sizeof(*ci))
1386 		return -EINVAL;
1387 
1388 	size = sizeof(req) + req.conn_num * sizeof(*ci);
1389 
1390 	cl = kmalloc(size, GFP_KERNEL);
1391 	if (!cl)
1392 		return -ENOMEM;
1393 
1394 	hdev = hci_dev_get(req.dev_id);
1395 	if (!hdev) {
1396 		kfree(cl);
1397 		return -ENODEV;
1398 	}
1399 
1400 	ci = cl->conn_info;
1401 
1402 	hci_dev_lock(hdev);
1403 	list_for_each_entry(c, &hdev->conn_hash.list, list) {
1404 		bacpy(&(ci + n)->bdaddr, &c->dst);
1405 		(ci + n)->handle = c->handle;
1406 		(ci + n)->type  = c->type;
1407 		(ci + n)->out   = c->out;
1408 		(ci + n)->state = c->state;
1409 		(ci + n)->link_mode = get_link_mode(c);
1410 		if (++n >= req.conn_num)
1411 			break;
1412 	}
1413 	hci_dev_unlock(hdev);
1414 
1415 	cl->dev_id = hdev->id;
1416 	cl->conn_num = n;
1417 	size = sizeof(req) + n * sizeof(*ci);
1418 
1419 	hci_dev_put(hdev);
1420 
1421 	err = copy_to_user(arg, cl, size);
1422 	kfree(cl);
1423 
1424 	return err ? -EFAULT : 0;
1425 }
1426 
1427 int hci_get_conn_info(struct hci_dev *hdev, void __user *arg)
1428 {
1429 	struct hci_conn_info_req req;
1430 	struct hci_conn_info ci;
1431 	struct hci_conn *conn;
1432 	char __user *ptr = arg + sizeof(req);
1433 
1434 	if (copy_from_user(&req, arg, sizeof(req)))
1435 		return -EFAULT;
1436 
1437 	hci_dev_lock(hdev);
1438 	conn = hci_conn_hash_lookup_ba(hdev, req.type, &req.bdaddr);
1439 	if (conn) {
1440 		bacpy(&ci.bdaddr, &conn->dst);
1441 		ci.handle = conn->handle;
1442 		ci.type  = conn->type;
1443 		ci.out   = conn->out;
1444 		ci.state = conn->state;
1445 		ci.link_mode = get_link_mode(conn);
1446 	}
1447 	hci_dev_unlock(hdev);
1448 
1449 	if (!conn)
1450 		return -ENOENT;
1451 
1452 	return copy_to_user(ptr, &ci, sizeof(ci)) ? -EFAULT : 0;
1453 }
1454 
1455 int hci_get_auth_info(struct hci_dev *hdev, void __user *arg)
1456 {
1457 	struct hci_auth_info_req req;
1458 	struct hci_conn *conn;
1459 
1460 	if (copy_from_user(&req, arg, sizeof(req)))
1461 		return -EFAULT;
1462 
1463 	hci_dev_lock(hdev);
1464 	conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, &req.bdaddr);
1465 	if (conn)
1466 		req.type = conn->auth_type;
1467 	hci_dev_unlock(hdev);
1468 
1469 	if (!conn)
1470 		return -ENOENT;
1471 
1472 	return copy_to_user(arg, &req, sizeof(req)) ? -EFAULT : 0;
1473 }
1474 
1475 struct hci_chan *hci_chan_create(struct hci_conn *conn)
1476 {
1477 	struct hci_dev *hdev = conn->hdev;
1478 	struct hci_chan *chan;
1479 
1480 	BT_DBG("%s hcon %p", hdev->name, conn);
1481 
1482 	if (test_bit(HCI_CONN_DROP, &conn->flags)) {
1483 		BT_DBG("Refusing to create new hci_chan");
1484 		return NULL;
1485 	}
1486 
1487 	chan = kzalloc(sizeof(*chan), GFP_KERNEL);
1488 	if (!chan)
1489 		return NULL;
1490 
1491 	chan->conn = hci_conn_get(conn);
1492 	skb_queue_head_init(&chan->data_q);
1493 	chan->state = BT_CONNECTED;
1494 
1495 	list_add_rcu(&chan->list, &conn->chan_list);
1496 
1497 	return chan;
1498 }
1499 
1500 void hci_chan_del(struct hci_chan *chan)
1501 {
1502 	struct hci_conn *conn = chan->conn;
1503 	struct hci_dev *hdev = conn->hdev;
1504 
1505 	BT_DBG("%s hcon %p chan %p", hdev->name, conn, chan);
1506 
1507 	list_del_rcu(&chan->list);
1508 
1509 	synchronize_rcu();
1510 
1511 	/* Prevent new hci_chan's to be created for this hci_conn */
1512 	set_bit(HCI_CONN_DROP, &conn->flags);
1513 
1514 	hci_conn_put(conn);
1515 
1516 	skb_queue_purge(&chan->data_q);
1517 	kfree(chan);
1518 }
1519 
1520 void hci_chan_list_flush(struct hci_conn *conn)
1521 {
1522 	struct hci_chan *chan, *n;
1523 
1524 	BT_DBG("hcon %p", conn);
1525 
1526 	list_for_each_entry_safe(chan, n, &conn->chan_list, list)
1527 		hci_chan_del(chan);
1528 }
1529 
1530 static struct hci_chan *__hci_chan_lookup_handle(struct hci_conn *hcon,
1531 						 __u16 handle)
1532 {
1533 	struct hci_chan *hchan;
1534 
1535 	list_for_each_entry(hchan, &hcon->chan_list, list) {
1536 		if (hchan->handle == handle)
1537 			return hchan;
1538 	}
1539 
1540 	return NULL;
1541 }
1542 
1543 struct hci_chan *hci_chan_lookup_handle(struct hci_dev *hdev, __u16 handle)
1544 {
1545 	struct hci_conn_hash *h = &hdev->conn_hash;
1546 	struct hci_conn *hcon;
1547 	struct hci_chan *hchan = NULL;
1548 
1549 	rcu_read_lock();
1550 
1551 	list_for_each_entry_rcu(hcon, &h->list, list) {
1552 		hchan = __hci_chan_lookup_handle(hcon, handle);
1553 		if (hchan)
1554 			break;
1555 	}
1556 
1557 	rcu_read_unlock();
1558 
1559 	return hchan;
1560 }
1561