xref: /openbmc/linux/net/bluetooth/hci_conn.c (revision 47010c04)
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_passive_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 (conn->type == SCO_LINK || conn->type == ESCO_LINK) {
126 		switch (conn->setting & SCO_AIRMODE_MASK) {
127 		case SCO_AIRMODE_CVSD:
128 		case SCO_AIRMODE_TRANSP:
129 			if (hdev->notify)
130 				hdev->notify(hdev, HCI_NOTIFY_DISABLE_SCO);
131 			break;
132 		}
133 	} else {
134 		if (hdev->notify)
135 			hdev->notify(hdev, HCI_NOTIFY_CONN_DEL);
136 	}
137 
138 	hci_conn_del_sysfs(conn);
139 
140 	debugfs_remove_recursive(conn->debugfs);
141 
142 	hci_dev_put(hdev);
143 
144 	hci_conn_put(conn);
145 }
146 
147 static void le_scan_cleanup(struct work_struct *work)
148 {
149 	struct hci_conn *conn = container_of(work, struct hci_conn,
150 					     le_scan_cleanup);
151 	struct hci_dev *hdev = conn->hdev;
152 	struct hci_conn *c = NULL;
153 
154 	BT_DBG("%s hcon %p", hdev->name, conn);
155 
156 	hci_dev_lock(hdev);
157 
158 	/* Check that the hci_conn is still around */
159 	rcu_read_lock();
160 	list_for_each_entry_rcu(c, &hdev->conn_hash.list, list) {
161 		if (c == conn)
162 			break;
163 	}
164 	rcu_read_unlock();
165 
166 	if (c == conn) {
167 		hci_connect_le_scan_cleanup(conn);
168 		hci_conn_cleanup(conn);
169 	}
170 
171 	hci_dev_unlock(hdev);
172 	hci_dev_put(hdev);
173 	hci_conn_put(conn);
174 }
175 
176 static void hci_connect_le_scan_remove(struct hci_conn *conn)
177 {
178 	BT_DBG("%s hcon %p", conn->hdev->name, conn);
179 
180 	/* We can't call hci_conn_del/hci_conn_cleanup here since that
181 	 * could deadlock with another hci_conn_del() call that's holding
182 	 * hci_dev_lock and doing cancel_delayed_work_sync(&conn->disc_work).
183 	 * Instead, grab temporary extra references to the hci_dev and
184 	 * hci_conn and perform the necessary cleanup in a separate work
185 	 * callback.
186 	 */
187 
188 	hci_dev_hold(conn->hdev);
189 	hci_conn_get(conn);
190 
191 	/* Even though we hold a reference to the hdev, many other
192 	 * things might get cleaned up meanwhile, including the hdev's
193 	 * own workqueue, so we can't use that for scheduling.
194 	 */
195 	schedule_work(&conn->le_scan_cleanup);
196 }
197 
198 static void hci_acl_create_connection(struct hci_conn *conn)
199 {
200 	struct hci_dev *hdev = conn->hdev;
201 	struct inquiry_entry *ie;
202 	struct hci_cp_create_conn cp;
203 
204 	BT_DBG("hcon %p", conn);
205 
206 	/* Many controllers disallow HCI Create Connection while it is doing
207 	 * HCI Inquiry. So we cancel the Inquiry first before issuing HCI Create
208 	 * Connection. This may cause the MGMT discovering state to become false
209 	 * without user space's request but it is okay since the MGMT Discovery
210 	 * APIs do not promise that discovery should be done forever. Instead,
211 	 * the user space monitors the status of MGMT discovering and it may
212 	 * request for discovery again when this flag becomes false.
213 	 */
214 	if (test_bit(HCI_INQUIRY, &hdev->flags)) {
215 		/* Put this connection to "pending" state so that it will be
216 		 * executed after the inquiry cancel command complete event.
217 		 */
218 		conn->state = BT_CONNECT2;
219 		hci_send_cmd(hdev, HCI_OP_INQUIRY_CANCEL, 0, NULL);
220 		return;
221 	}
222 
223 	conn->state = BT_CONNECT;
224 	conn->out = true;
225 	conn->role = HCI_ROLE_MASTER;
226 
227 	conn->attempt++;
228 
229 	conn->link_policy = hdev->link_policy;
230 
231 	memset(&cp, 0, sizeof(cp));
232 	bacpy(&cp.bdaddr, &conn->dst);
233 	cp.pscan_rep_mode = 0x02;
234 
235 	ie = hci_inquiry_cache_lookup(hdev, &conn->dst);
236 	if (ie) {
237 		if (inquiry_entry_age(ie) <= INQUIRY_ENTRY_AGE_MAX) {
238 			cp.pscan_rep_mode = ie->data.pscan_rep_mode;
239 			cp.pscan_mode     = ie->data.pscan_mode;
240 			cp.clock_offset   = ie->data.clock_offset |
241 					    cpu_to_le16(0x8000);
242 		}
243 
244 		memcpy(conn->dev_class, ie->data.dev_class, 3);
245 	}
246 
247 	cp.pkt_type = cpu_to_le16(conn->pkt_type);
248 	if (lmp_rswitch_capable(hdev) && !(hdev->link_mode & HCI_LM_MASTER))
249 		cp.role_switch = 0x01;
250 	else
251 		cp.role_switch = 0x00;
252 
253 	hci_send_cmd(hdev, HCI_OP_CREATE_CONN, sizeof(cp), &cp);
254 }
255 
256 int hci_disconnect(struct hci_conn *conn, __u8 reason)
257 {
258 	BT_DBG("hcon %p", conn);
259 
260 	/* When we are central of an established connection and it enters
261 	 * the disconnect timeout, then go ahead and try to read the
262 	 * current clock offset.  Processing of the result is done
263 	 * within the event handling and hci_clock_offset_evt function.
264 	 */
265 	if (conn->type == ACL_LINK && conn->role == HCI_ROLE_MASTER &&
266 	    (conn->state == BT_CONNECTED || conn->state == BT_CONFIG)) {
267 		struct hci_dev *hdev = conn->hdev;
268 		struct hci_cp_read_clock_offset clkoff_cp;
269 
270 		clkoff_cp.handle = cpu_to_le16(conn->handle);
271 		hci_send_cmd(hdev, HCI_OP_READ_CLOCK_OFFSET, sizeof(clkoff_cp),
272 			     &clkoff_cp);
273 	}
274 
275 	return hci_abort_conn(conn, reason);
276 }
277 
278 static void hci_add_sco(struct hci_conn *conn, __u16 handle)
279 {
280 	struct hci_dev *hdev = conn->hdev;
281 	struct hci_cp_add_sco cp;
282 
283 	BT_DBG("hcon %p", conn);
284 
285 	conn->state = BT_CONNECT;
286 	conn->out = true;
287 
288 	conn->attempt++;
289 
290 	cp.handle   = cpu_to_le16(handle);
291 	cp.pkt_type = cpu_to_le16(conn->pkt_type);
292 
293 	hci_send_cmd(hdev, HCI_OP_ADD_SCO, sizeof(cp), &cp);
294 }
295 
296 static bool find_next_esco_param(struct hci_conn *conn,
297 				 const struct sco_param *esco_param, int size)
298 {
299 	for (; conn->attempt <= size; conn->attempt++) {
300 		if (lmp_esco_2m_capable(conn->link) ||
301 		    (esco_param[conn->attempt - 1].pkt_type & ESCO_2EV3))
302 			break;
303 		BT_DBG("hcon %p skipped attempt %d, eSCO 2M not supported",
304 		       conn, conn->attempt);
305 	}
306 
307 	return conn->attempt <= size;
308 }
309 
310 static bool hci_enhanced_setup_sync_conn(struct hci_conn *conn, __u16 handle)
311 {
312 	struct hci_dev *hdev = conn->hdev;
313 	struct hci_cp_enhanced_setup_sync_conn cp;
314 	const struct sco_param *param;
315 
316 	bt_dev_dbg(hdev, "hcon %p", conn);
317 
318 	/* for offload use case, codec needs to configured before opening SCO */
319 	if (conn->codec.data_path)
320 		hci_req_configure_datapath(hdev, &conn->codec);
321 
322 	conn->state = BT_CONNECT;
323 	conn->out = true;
324 
325 	conn->attempt++;
326 
327 	memset(&cp, 0x00, sizeof(cp));
328 
329 	cp.handle   = cpu_to_le16(handle);
330 
331 	cp.tx_bandwidth   = cpu_to_le32(0x00001f40);
332 	cp.rx_bandwidth   = cpu_to_le32(0x00001f40);
333 
334 	switch (conn->codec.id) {
335 	case BT_CODEC_MSBC:
336 		if (!find_next_esco_param(conn, esco_param_msbc,
337 					  ARRAY_SIZE(esco_param_msbc)))
338 			return false;
339 
340 		param = &esco_param_msbc[conn->attempt - 1];
341 		cp.tx_coding_format.id = 0x05;
342 		cp.rx_coding_format.id = 0x05;
343 		cp.tx_codec_frame_size = __cpu_to_le16(60);
344 		cp.rx_codec_frame_size = __cpu_to_le16(60);
345 		cp.in_bandwidth = __cpu_to_le32(32000);
346 		cp.out_bandwidth = __cpu_to_le32(32000);
347 		cp.in_coding_format.id = 0x04;
348 		cp.out_coding_format.id = 0x04;
349 		cp.in_coded_data_size = __cpu_to_le16(16);
350 		cp.out_coded_data_size = __cpu_to_le16(16);
351 		cp.in_pcm_data_format = 2;
352 		cp.out_pcm_data_format = 2;
353 		cp.in_pcm_sample_payload_msb_pos = 0;
354 		cp.out_pcm_sample_payload_msb_pos = 0;
355 		cp.in_data_path = conn->codec.data_path;
356 		cp.out_data_path = conn->codec.data_path;
357 		cp.in_transport_unit_size = 1;
358 		cp.out_transport_unit_size = 1;
359 		break;
360 
361 	case BT_CODEC_TRANSPARENT:
362 		if (!find_next_esco_param(conn, esco_param_msbc,
363 					  ARRAY_SIZE(esco_param_msbc)))
364 			return false;
365 		param = &esco_param_msbc[conn->attempt - 1];
366 		cp.tx_coding_format.id = 0x03;
367 		cp.rx_coding_format.id = 0x03;
368 		cp.tx_codec_frame_size = __cpu_to_le16(60);
369 		cp.rx_codec_frame_size = __cpu_to_le16(60);
370 		cp.in_bandwidth = __cpu_to_le32(0x1f40);
371 		cp.out_bandwidth = __cpu_to_le32(0x1f40);
372 		cp.in_coding_format.id = 0x03;
373 		cp.out_coding_format.id = 0x03;
374 		cp.in_coded_data_size = __cpu_to_le16(16);
375 		cp.out_coded_data_size = __cpu_to_le16(16);
376 		cp.in_pcm_data_format = 2;
377 		cp.out_pcm_data_format = 2;
378 		cp.in_pcm_sample_payload_msb_pos = 0;
379 		cp.out_pcm_sample_payload_msb_pos = 0;
380 		cp.in_data_path = conn->codec.data_path;
381 		cp.out_data_path = conn->codec.data_path;
382 		cp.in_transport_unit_size = 1;
383 		cp.out_transport_unit_size = 1;
384 		break;
385 
386 	case BT_CODEC_CVSD:
387 		if (lmp_esco_capable(conn->link)) {
388 			if (!find_next_esco_param(conn, esco_param_cvsd,
389 						  ARRAY_SIZE(esco_param_cvsd)))
390 				return false;
391 			param = &esco_param_cvsd[conn->attempt - 1];
392 		} else {
393 			if (conn->attempt > ARRAY_SIZE(sco_param_cvsd))
394 				return false;
395 			param = &sco_param_cvsd[conn->attempt - 1];
396 		}
397 		cp.tx_coding_format.id = 2;
398 		cp.rx_coding_format.id = 2;
399 		cp.tx_codec_frame_size = __cpu_to_le16(60);
400 		cp.rx_codec_frame_size = __cpu_to_le16(60);
401 		cp.in_bandwidth = __cpu_to_le32(16000);
402 		cp.out_bandwidth = __cpu_to_le32(16000);
403 		cp.in_coding_format.id = 4;
404 		cp.out_coding_format.id = 4;
405 		cp.in_coded_data_size = __cpu_to_le16(16);
406 		cp.out_coded_data_size = __cpu_to_le16(16);
407 		cp.in_pcm_data_format = 2;
408 		cp.out_pcm_data_format = 2;
409 		cp.in_pcm_sample_payload_msb_pos = 0;
410 		cp.out_pcm_sample_payload_msb_pos = 0;
411 		cp.in_data_path = conn->codec.data_path;
412 		cp.out_data_path = conn->codec.data_path;
413 		cp.in_transport_unit_size = 16;
414 		cp.out_transport_unit_size = 16;
415 		break;
416 	default:
417 		return false;
418 	}
419 
420 	cp.retrans_effort = param->retrans_effort;
421 	cp.pkt_type = __cpu_to_le16(param->pkt_type);
422 	cp.max_latency = __cpu_to_le16(param->max_latency);
423 
424 	if (hci_send_cmd(hdev, HCI_OP_ENHANCED_SETUP_SYNC_CONN, sizeof(cp), &cp) < 0)
425 		return false;
426 
427 	return true;
428 }
429 
430 static bool hci_setup_sync_conn(struct hci_conn *conn, __u16 handle)
431 {
432 	struct hci_dev *hdev = conn->hdev;
433 	struct hci_cp_setup_sync_conn cp;
434 	const struct sco_param *param;
435 
436 	bt_dev_dbg(hdev, "hcon %p", conn);
437 
438 	conn->state = BT_CONNECT;
439 	conn->out = true;
440 
441 	conn->attempt++;
442 
443 	cp.handle   = cpu_to_le16(handle);
444 
445 	cp.tx_bandwidth   = cpu_to_le32(0x00001f40);
446 	cp.rx_bandwidth   = cpu_to_le32(0x00001f40);
447 	cp.voice_setting  = cpu_to_le16(conn->setting);
448 
449 	switch (conn->setting & SCO_AIRMODE_MASK) {
450 	case SCO_AIRMODE_TRANSP:
451 		if (!find_next_esco_param(conn, esco_param_msbc,
452 					  ARRAY_SIZE(esco_param_msbc)))
453 			return false;
454 		param = &esco_param_msbc[conn->attempt - 1];
455 		break;
456 	case SCO_AIRMODE_CVSD:
457 		if (lmp_esco_capable(conn->link)) {
458 			if (!find_next_esco_param(conn, esco_param_cvsd,
459 						  ARRAY_SIZE(esco_param_cvsd)))
460 				return false;
461 			param = &esco_param_cvsd[conn->attempt - 1];
462 		} else {
463 			if (conn->attempt > ARRAY_SIZE(sco_param_cvsd))
464 				return false;
465 			param = &sco_param_cvsd[conn->attempt - 1];
466 		}
467 		break;
468 	default:
469 		return false;
470 	}
471 
472 	cp.retrans_effort = param->retrans_effort;
473 	cp.pkt_type = __cpu_to_le16(param->pkt_type);
474 	cp.max_latency = __cpu_to_le16(param->max_latency);
475 
476 	if (hci_send_cmd(hdev, HCI_OP_SETUP_SYNC_CONN, sizeof(cp), &cp) < 0)
477 		return false;
478 
479 	return true;
480 }
481 
482 bool hci_setup_sync(struct hci_conn *conn, __u16 handle)
483 {
484 	if (enhanced_sco_capable(conn->hdev))
485 		return hci_enhanced_setup_sync_conn(conn, handle);
486 
487 	return hci_setup_sync_conn(conn, handle);
488 }
489 
490 u8 hci_le_conn_update(struct hci_conn *conn, u16 min, u16 max, u16 latency,
491 		      u16 to_multiplier)
492 {
493 	struct hci_dev *hdev = conn->hdev;
494 	struct hci_conn_params *params;
495 	struct hci_cp_le_conn_update cp;
496 
497 	hci_dev_lock(hdev);
498 
499 	params = hci_conn_params_lookup(hdev, &conn->dst, conn->dst_type);
500 	if (params) {
501 		params->conn_min_interval = min;
502 		params->conn_max_interval = max;
503 		params->conn_latency = latency;
504 		params->supervision_timeout = to_multiplier;
505 	}
506 
507 	hci_dev_unlock(hdev);
508 
509 	memset(&cp, 0, sizeof(cp));
510 	cp.handle		= cpu_to_le16(conn->handle);
511 	cp.conn_interval_min	= cpu_to_le16(min);
512 	cp.conn_interval_max	= cpu_to_le16(max);
513 	cp.conn_latency		= cpu_to_le16(latency);
514 	cp.supervision_timeout	= cpu_to_le16(to_multiplier);
515 	cp.min_ce_len		= cpu_to_le16(0x0000);
516 	cp.max_ce_len		= cpu_to_le16(0x0000);
517 
518 	hci_send_cmd(hdev, HCI_OP_LE_CONN_UPDATE, sizeof(cp), &cp);
519 
520 	if (params)
521 		return 0x01;
522 
523 	return 0x00;
524 }
525 
526 void hci_le_start_enc(struct hci_conn *conn, __le16 ediv, __le64 rand,
527 		      __u8 ltk[16], __u8 key_size)
528 {
529 	struct hci_dev *hdev = conn->hdev;
530 	struct hci_cp_le_start_enc cp;
531 
532 	BT_DBG("hcon %p", conn);
533 
534 	memset(&cp, 0, sizeof(cp));
535 
536 	cp.handle = cpu_to_le16(conn->handle);
537 	cp.rand = rand;
538 	cp.ediv = ediv;
539 	memcpy(cp.ltk, ltk, key_size);
540 
541 	hci_send_cmd(hdev, HCI_OP_LE_START_ENC, sizeof(cp), &cp);
542 }
543 
544 /* Device _must_ be locked */
545 void hci_sco_setup(struct hci_conn *conn, __u8 status)
546 {
547 	struct hci_conn *sco = conn->link;
548 
549 	if (!sco)
550 		return;
551 
552 	BT_DBG("hcon %p", conn);
553 
554 	if (!status) {
555 		if (lmp_esco_capable(conn->hdev))
556 			hci_setup_sync(sco, conn->handle);
557 		else
558 			hci_add_sco(sco, conn->handle);
559 	} else {
560 		hci_connect_cfm(sco, status);
561 		hci_conn_del(sco);
562 	}
563 }
564 
565 static void hci_conn_timeout(struct work_struct *work)
566 {
567 	struct hci_conn *conn = container_of(work, struct hci_conn,
568 					     disc_work.work);
569 	int refcnt = atomic_read(&conn->refcnt);
570 
571 	BT_DBG("hcon %p state %s", conn, state_to_string(conn->state));
572 
573 	WARN_ON(refcnt < 0);
574 
575 	/* FIXME: It was observed that in pairing failed scenario, refcnt
576 	 * drops below 0. Probably this is because l2cap_conn_del calls
577 	 * l2cap_chan_del for each channel, and inside l2cap_chan_del conn is
578 	 * dropped. After that loop hci_chan_del is called which also drops
579 	 * conn. For now make sure that ACL is alive if refcnt is higher then 0,
580 	 * otherwise drop it.
581 	 */
582 	if (refcnt > 0)
583 		return;
584 
585 	/* LE connections in scanning state need special handling */
586 	if (conn->state == BT_CONNECT && conn->type == LE_LINK &&
587 	    test_bit(HCI_CONN_SCANNING, &conn->flags)) {
588 		hci_connect_le_scan_remove(conn);
589 		return;
590 	}
591 
592 	hci_abort_conn(conn, hci_proto_disconn_ind(conn));
593 }
594 
595 /* Enter sniff mode */
596 static void hci_conn_idle(struct work_struct *work)
597 {
598 	struct hci_conn *conn = container_of(work, struct hci_conn,
599 					     idle_work.work);
600 	struct hci_dev *hdev = conn->hdev;
601 
602 	BT_DBG("hcon %p mode %d", conn, conn->mode);
603 
604 	if (!lmp_sniff_capable(hdev) || !lmp_sniff_capable(conn))
605 		return;
606 
607 	if (conn->mode != HCI_CM_ACTIVE || !(conn->link_policy & HCI_LP_SNIFF))
608 		return;
609 
610 	if (lmp_sniffsubr_capable(hdev) && lmp_sniffsubr_capable(conn)) {
611 		struct hci_cp_sniff_subrate cp;
612 		cp.handle             = cpu_to_le16(conn->handle);
613 		cp.max_latency        = cpu_to_le16(0);
614 		cp.min_remote_timeout = cpu_to_le16(0);
615 		cp.min_local_timeout  = cpu_to_le16(0);
616 		hci_send_cmd(hdev, HCI_OP_SNIFF_SUBRATE, sizeof(cp), &cp);
617 	}
618 
619 	if (!test_and_set_bit(HCI_CONN_MODE_CHANGE_PEND, &conn->flags)) {
620 		struct hci_cp_sniff_mode cp;
621 		cp.handle       = cpu_to_le16(conn->handle);
622 		cp.max_interval = cpu_to_le16(hdev->sniff_max_interval);
623 		cp.min_interval = cpu_to_le16(hdev->sniff_min_interval);
624 		cp.attempt      = cpu_to_le16(4);
625 		cp.timeout      = cpu_to_le16(1);
626 		hci_send_cmd(hdev, HCI_OP_SNIFF_MODE, sizeof(cp), &cp);
627 	}
628 }
629 
630 static void hci_conn_auto_accept(struct work_struct *work)
631 {
632 	struct hci_conn *conn = container_of(work, struct hci_conn,
633 					     auto_accept_work.work);
634 
635 	hci_send_cmd(conn->hdev, HCI_OP_USER_CONFIRM_REPLY, sizeof(conn->dst),
636 		     &conn->dst);
637 }
638 
639 static void le_disable_advertising(struct hci_dev *hdev)
640 {
641 	if (ext_adv_capable(hdev)) {
642 		struct hci_cp_le_set_ext_adv_enable cp;
643 
644 		cp.enable = 0x00;
645 		cp.num_of_sets = 0x00;
646 
647 		hci_send_cmd(hdev, HCI_OP_LE_SET_EXT_ADV_ENABLE, sizeof(cp),
648 			     &cp);
649 	} else {
650 		u8 enable = 0x00;
651 		hci_send_cmd(hdev, HCI_OP_LE_SET_ADV_ENABLE, sizeof(enable),
652 			     &enable);
653 	}
654 }
655 
656 static void le_conn_timeout(struct work_struct *work)
657 {
658 	struct hci_conn *conn = container_of(work, struct hci_conn,
659 					     le_conn_timeout.work);
660 	struct hci_dev *hdev = conn->hdev;
661 
662 	BT_DBG("");
663 
664 	/* We could end up here due to having done directed advertising,
665 	 * so clean up the state if necessary. This should however only
666 	 * happen with broken hardware or if low duty cycle was used
667 	 * (which doesn't have a timeout of its own).
668 	 */
669 	if (conn->role == HCI_ROLE_SLAVE) {
670 		/* Disable LE Advertising */
671 		le_disable_advertising(hdev);
672 		hci_dev_lock(hdev);
673 		hci_conn_failed(conn, HCI_ERROR_ADVERTISING_TIMEOUT);
674 		hci_dev_unlock(hdev);
675 		return;
676 	}
677 
678 	hci_abort_conn(conn, HCI_ERROR_REMOTE_USER_TERM);
679 }
680 
681 struct hci_conn *hci_conn_add(struct hci_dev *hdev, int type, bdaddr_t *dst,
682 			      u8 role)
683 {
684 	struct hci_conn *conn;
685 
686 	BT_DBG("%s dst %pMR", hdev->name, dst);
687 
688 	conn = kzalloc(sizeof(*conn), GFP_KERNEL);
689 	if (!conn)
690 		return NULL;
691 
692 	bacpy(&conn->dst, dst);
693 	bacpy(&conn->src, &hdev->bdaddr);
694 	conn->handle = HCI_CONN_HANDLE_UNSET;
695 	conn->hdev  = hdev;
696 	conn->type  = type;
697 	conn->role  = role;
698 	conn->mode  = HCI_CM_ACTIVE;
699 	conn->state = BT_OPEN;
700 	conn->auth_type = HCI_AT_GENERAL_BONDING;
701 	conn->io_capability = hdev->io_capability;
702 	conn->remote_auth = 0xff;
703 	conn->key_type = 0xff;
704 	conn->rssi = HCI_RSSI_INVALID;
705 	conn->tx_power = HCI_TX_POWER_INVALID;
706 	conn->max_tx_power = HCI_TX_POWER_INVALID;
707 
708 	set_bit(HCI_CONN_POWER_SAVE, &conn->flags);
709 	conn->disc_timeout = HCI_DISCONN_TIMEOUT;
710 
711 	/* Set Default Authenticated payload timeout to 30s */
712 	conn->auth_payload_timeout = DEFAULT_AUTH_PAYLOAD_TIMEOUT;
713 
714 	if (conn->role == HCI_ROLE_MASTER)
715 		conn->out = true;
716 
717 	switch (type) {
718 	case ACL_LINK:
719 		conn->pkt_type = hdev->pkt_type & ACL_PTYPE_MASK;
720 		break;
721 	case LE_LINK:
722 		/* conn->src should reflect the local identity address */
723 		hci_copy_identity_address(hdev, &conn->src, &conn->src_type);
724 		break;
725 	case SCO_LINK:
726 		if (lmp_esco_capable(hdev))
727 			conn->pkt_type = (hdev->esco_type & SCO_ESCO_MASK) |
728 					(hdev->esco_type & EDR_ESCO_MASK);
729 		else
730 			conn->pkt_type = hdev->pkt_type & SCO_PTYPE_MASK;
731 		break;
732 	case ESCO_LINK:
733 		conn->pkt_type = hdev->esco_type & ~EDR_ESCO_MASK;
734 		break;
735 	}
736 
737 	skb_queue_head_init(&conn->data_q);
738 
739 	INIT_LIST_HEAD(&conn->chan_list);
740 
741 	INIT_DELAYED_WORK(&conn->disc_work, hci_conn_timeout);
742 	INIT_DELAYED_WORK(&conn->auto_accept_work, hci_conn_auto_accept);
743 	INIT_DELAYED_WORK(&conn->idle_work, hci_conn_idle);
744 	INIT_DELAYED_WORK(&conn->le_conn_timeout, le_conn_timeout);
745 	INIT_WORK(&conn->le_scan_cleanup, le_scan_cleanup);
746 
747 	atomic_set(&conn->refcnt, 0);
748 
749 	hci_dev_hold(hdev);
750 
751 	hci_conn_hash_add(hdev, conn);
752 
753 	/* The SCO and eSCO connections will only be notified when their
754 	 * setup has been completed. This is different to ACL links which
755 	 * can be notified right away.
756 	 */
757 	if (conn->type != SCO_LINK && conn->type != ESCO_LINK) {
758 		if (hdev->notify)
759 			hdev->notify(hdev, HCI_NOTIFY_CONN_ADD);
760 	}
761 
762 	hci_conn_init_sysfs(conn);
763 
764 	return conn;
765 }
766 
767 int hci_conn_del(struct hci_conn *conn)
768 {
769 	struct hci_dev *hdev = conn->hdev;
770 
771 	BT_DBG("%s hcon %p handle %d", hdev->name, conn, conn->handle);
772 
773 	cancel_delayed_work_sync(&conn->disc_work);
774 	cancel_delayed_work_sync(&conn->auto_accept_work);
775 	cancel_delayed_work_sync(&conn->idle_work);
776 
777 	if (conn->type == ACL_LINK) {
778 		struct hci_conn *sco = conn->link;
779 		if (sco)
780 			sco->link = NULL;
781 
782 		/* Unacked frames */
783 		hdev->acl_cnt += conn->sent;
784 	} else if (conn->type == LE_LINK) {
785 		cancel_delayed_work(&conn->le_conn_timeout);
786 
787 		if (hdev->le_pkts)
788 			hdev->le_cnt += conn->sent;
789 		else
790 			hdev->acl_cnt += conn->sent;
791 	} else {
792 		struct hci_conn *acl = conn->link;
793 		if (acl) {
794 			acl->link = NULL;
795 			hci_conn_drop(acl);
796 		}
797 	}
798 
799 	if (conn->amp_mgr)
800 		amp_mgr_put(conn->amp_mgr);
801 
802 	skb_queue_purge(&conn->data_q);
803 
804 	/* Remove the connection from the list and cleanup its remaining
805 	 * state. This is a separate function since for some cases like
806 	 * BT_CONNECT_SCAN we *only* want the cleanup part without the
807 	 * rest of hci_conn_del.
808 	 */
809 	hci_conn_cleanup(conn);
810 
811 	return 0;
812 }
813 
814 struct hci_dev *hci_get_route(bdaddr_t *dst, bdaddr_t *src, uint8_t src_type)
815 {
816 	int use_src = bacmp(src, BDADDR_ANY);
817 	struct hci_dev *hdev = NULL, *d;
818 
819 	BT_DBG("%pMR -> %pMR", src, dst);
820 
821 	read_lock(&hci_dev_list_lock);
822 
823 	list_for_each_entry(d, &hci_dev_list, list) {
824 		if (!test_bit(HCI_UP, &d->flags) ||
825 		    hci_dev_test_flag(d, HCI_USER_CHANNEL) ||
826 		    d->dev_type != HCI_PRIMARY)
827 			continue;
828 
829 		/* Simple routing:
830 		 *   No source address - find interface with bdaddr != dst
831 		 *   Source address    - find interface with bdaddr == src
832 		 */
833 
834 		if (use_src) {
835 			bdaddr_t id_addr;
836 			u8 id_addr_type;
837 
838 			if (src_type == BDADDR_BREDR) {
839 				if (!lmp_bredr_capable(d))
840 					continue;
841 				bacpy(&id_addr, &d->bdaddr);
842 				id_addr_type = BDADDR_BREDR;
843 			} else {
844 				if (!lmp_le_capable(d))
845 					continue;
846 
847 				hci_copy_identity_address(d, &id_addr,
848 							  &id_addr_type);
849 
850 				/* Convert from HCI to three-value type */
851 				if (id_addr_type == ADDR_LE_DEV_PUBLIC)
852 					id_addr_type = BDADDR_LE_PUBLIC;
853 				else
854 					id_addr_type = BDADDR_LE_RANDOM;
855 			}
856 
857 			if (!bacmp(&id_addr, src) && id_addr_type == src_type) {
858 				hdev = d; break;
859 			}
860 		} else {
861 			if (bacmp(&d->bdaddr, dst)) {
862 				hdev = d; break;
863 			}
864 		}
865 	}
866 
867 	if (hdev)
868 		hdev = hci_dev_hold(hdev);
869 
870 	read_unlock(&hci_dev_list_lock);
871 	return hdev;
872 }
873 EXPORT_SYMBOL(hci_get_route);
874 
875 /* This function requires the caller holds hdev->lock */
876 static void hci_le_conn_failed(struct hci_conn *conn, u8 status)
877 {
878 	struct hci_dev *hdev = conn->hdev;
879 	struct hci_conn_params *params;
880 
881 	params = hci_pend_le_action_lookup(&hdev->pend_le_conns, &conn->dst,
882 					   conn->dst_type);
883 	if (params && params->conn) {
884 		hci_conn_drop(params->conn);
885 		hci_conn_put(params->conn);
886 		params->conn = NULL;
887 	}
888 
889 	/* If the status indicates successful cancellation of
890 	 * the attempt (i.e. Unknown Connection Id) there's no point of
891 	 * notifying failure since we'll go back to keep trying to
892 	 * connect. The only exception is explicit connect requests
893 	 * where a timeout + cancel does indicate an actual failure.
894 	 */
895 	if (status != HCI_ERROR_UNKNOWN_CONN_ID ||
896 	    (params && params->explicit_connect))
897 		mgmt_connect_failed(hdev, &conn->dst, conn->type,
898 				    conn->dst_type, status);
899 
900 	/* Since we may have temporarily stopped the background scanning in
901 	 * favor of connection establishment, we should restart it.
902 	 */
903 	hci_update_passive_scan(hdev);
904 
905 	/* Enable advertising in case this was a failed connection
906 	 * attempt as a peripheral.
907 	 */
908 	hci_enable_advertising(hdev);
909 }
910 
911 /* This function requires the caller holds hdev->lock */
912 void hci_conn_failed(struct hci_conn *conn, u8 status)
913 {
914 	struct hci_dev *hdev = conn->hdev;
915 
916 	bt_dev_dbg(hdev, "status 0x%2.2x", status);
917 
918 	switch (conn->type) {
919 	case LE_LINK:
920 		hci_le_conn_failed(conn, status);
921 		break;
922 	case ACL_LINK:
923 		mgmt_connect_failed(hdev, &conn->dst, conn->type,
924 				    conn->dst_type, status);
925 		break;
926 	}
927 
928 	conn->state = BT_CLOSED;
929 	hci_connect_cfm(conn, status);
930 	hci_conn_del(conn);
931 }
932 
933 static void create_le_conn_complete(struct hci_dev *hdev, void *data, int err)
934 {
935 	struct hci_conn *conn = data;
936 
937 	hci_dev_lock(hdev);
938 
939 	if (!err) {
940 		hci_connect_le_scan_cleanup(conn);
941 		goto done;
942 	}
943 
944 	bt_dev_err(hdev, "request failed to create LE connection: err %d", err);
945 
946 	if (!conn)
947 		goto done;
948 
949 	hci_le_conn_failed(conn, err);
950 
951 done:
952 	hci_dev_unlock(hdev);
953 }
954 
955 static int hci_connect_le_sync(struct hci_dev *hdev, void *data)
956 {
957 	struct hci_conn *conn = data;
958 
959 	bt_dev_dbg(hdev, "conn %p", conn);
960 
961 	return hci_le_create_conn_sync(hdev, conn);
962 }
963 
964 struct hci_conn *hci_connect_le(struct hci_dev *hdev, bdaddr_t *dst,
965 				u8 dst_type, bool dst_resolved, u8 sec_level,
966 				u16 conn_timeout, u8 role)
967 {
968 	struct hci_conn *conn;
969 	struct smp_irk *irk;
970 	int err;
971 
972 	/* Let's make sure that le is enabled.*/
973 	if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED)) {
974 		if (lmp_le_capable(hdev))
975 			return ERR_PTR(-ECONNREFUSED);
976 
977 		return ERR_PTR(-EOPNOTSUPP);
978 	}
979 
980 	/* Since the controller supports only one LE connection attempt at a
981 	 * time, we return -EBUSY if there is any connection attempt running.
982 	 */
983 	if (hci_lookup_le_connect(hdev))
984 		return ERR_PTR(-EBUSY);
985 
986 	/* If there's already a connection object but it's not in
987 	 * scanning state it means it must already be established, in
988 	 * which case we can't do anything else except report a failure
989 	 * to connect.
990 	 */
991 	conn = hci_conn_hash_lookup_le(hdev, dst, dst_type);
992 	if (conn && !test_bit(HCI_CONN_SCANNING, &conn->flags)) {
993 		return ERR_PTR(-EBUSY);
994 	}
995 
996 	/* Check if the destination address has been resolved by the controller
997 	 * since if it did then the identity address shall be used.
998 	 */
999 	if (!dst_resolved) {
1000 		/* When given an identity address with existing identity
1001 		 * resolving key, the connection needs to be established
1002 		 * to a resolvable random address.
1003 		 *
1004 		 * Storing the resolvable random address is required here
1005 		 * to handle connection failures. The address will later
1006 		 * be resolved back into the original identity address
1007 		 * from the connect request.
1008 		 */
1009 		irk = hci_find_irk_by_addr(hdev, dst, dst_type);
1010 		if (irk && bacmp(&irk->rpa, BDADDR_ANY)) {
1011 			dst = &irk->rpa;
1012 			dst_type = ADDR_LE_DEV_RANDOM;
1013 		}
1014 	}
1015 
1016 	if (conn) {
1017 		bacpy(&conn->dst, dst);
1018 	} else {
1019 		conn = hci_conn_add(hdev, LE_LINK, dst, role);
1020 		if (!conn)
1021 			return ERR_PTR(-ENOMEM);
1022 		hci_conn_hold(conn);
1023 		conn->pending_sec_level = sec_level;
1024 	}
1025 
1026 	conn->dst_type = dst_type;
1027 	conn->sec_level = BT_SECURITY_LOW;
1028 	conn->conn_timeout = conn_timeout;
1029 
1030 	conn->state = BT_CONNECT;
1031 	clear_bit(HCI_CONN_SCANNING, &conn->flags);
1032 
1033 	err = hci_cmd_sync_queue(hdev, hci_connect_le_sync, conn,
1034 				 create_le_conn_complete);
1035 	if (err) {
1036 		hci_conn_del(conn);
1037 		return ERR_PTR(err);
1038 	}
1039 
1040 	return conn;
1041 }
1042 
1043 static bool is_connected(struct hci_dev *hdev, bdaddr_t *addr, u8 type)
1044 {
1045 	struct hci_conn *conn;
1046 
1047 	conn = hci_conn_hash_lookup_le(hdev, addr, type);
1048 	if (!conn)
1049 		return false;
1050 
1051 	if (conn->state != BT_CONNECTED)
1052 		return false;
1053 
1054 	return true;
1055 }
1056 
1057 /* This function requires the caller holds hdev->lock */
1058 static int hci_explicit_conn_params_set(struct hci_dev *hdev,
1059 					bdaddr_t *addr, u8 addr_type)
1060 {
1061 	struct hci_conn_params *params;
1062 
1063 	if (is_connected(hdev, addr, addr_type))
1064 		return -EISCONN;
1065 
1066 	params = hci_conn_params_lookup(hdev, addr, addr_type);
1067 	if (!params) {
1068 		params = hci_conn_params_add(hdev, addr, addr_type);
1069 		if (!params)
1070 			return -ENOMEM;
1071 
1072 		/* If we created new params, mark them to be deleted in
1073 		 * hci_connect_le_scan_cleanup. It's different case than
1074 		 * existing disabled params, those will stay after cleanup.
1075 		 */
1076 		params->auto_connect = HCI_AUTO_CONN_EXPLICIT;
1077 	}
1078 
1079 	/* We're trying to connect, so make sure params are at pend_le_conns */
1080 	if (params->auto_connect == HCI_AUTO_CONN_DISABLED ||
1081 	    params->auto_connect == HCI_AUTO_CONN_REPORT ||
1082 	    params->auto_connect == HCI_AUTO_CONN_EXPLICIT) {
1083 		list_del_init(&params->action);
1084 		list_add(&params->action, &hdev->pend_le_conns);
1085 	}
1086 
1087 	params->explicit_connect = true;
1088 
1089 	BT_DBG("addr %pMR (type %u) auto_connect %u", addr, addr_type,
1090 	       params->auto_connect);
1091 
1092 	return 0;
1093 }
1094 
1095 /* This function requires the caller holds hdev->lock */
1096 struct hci_conn *hci_connect_le_scan(struct hci_dev *hdev, bdaddr_t *dst,
1097 				     u8 dst_type, u8 sec_level,
1098 				     u16 conn_timeout,
1099 				     enum conn_reasons conn_reason)
1100 {
1101 	struct hci_conn *conn;
1102 
1103 	/* Let's make sure that le is enabled.*/
1104 	if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED)) {
1105 		if (lmp_le_capable(hdev))
1106 			return ERR_PTR(-ECONNREFUSED);
1107 
1108 		return ERR_PTR(-EOPNOTSUPP);
1109 	}
1110 
1111 	/* Some devices send ATT messages as soon as the physical link is
1112 	 * established. To be able to handle these ATT messages, the user-
1113 	 * space first establishes the connection and then starts the pairing
1114 	 * process.
1115 	 *
1116 	 * So if a hci_conn object already exists for the following connection
1117 	 * attempt, we simply update pending_sec_level and auth_type fields
1118 	 * and return the object found.
1119 	 */
1120 	conn = hci_conn_hash_lookup_le(hdev, dst, dst_type);
1121 	if (conn) {
1122 		if (conn->pending_sec_level < sec_level)
1123 			conn->pending_sec_level = sec_level;
1124 		goto done;
1125 	}
1126 
1127 	BT_DBG("requesting refresh of dst_addr");
1128 
1129 	conn = hci_conn_add(hdev, LE_LINK, dst, HCI_ROLE_MASTER);
1130 	if (!conn)
1131 		return ERR_PTR(-ENOMEM);
1132 
1133 	if (hci_explicit_conn_params_set(hdev, dst, dst_type) < 0) {
1134 		hci_conn_del(conn);
1135 		return ERR_PTR(-EBUSY);
1136 	}
1137 
1138 	conn->state = BT_CONNECT;
1139 	set_bit(HCI_CONN_SCANNING, &conn->flags);
1140 	conn->dst_type = dst_type;
1141 	conn->sec_level = BT_SECURITY_LOW;
1142 	conn->pending_sec_level = sec_level;
1143 	conn->conn_timeout = conn_timeout;
1144 	conn->conn_reason = conn_reason;
1145 
1146 	hci_update_passive_scan(hdev);
1147 
1148 done:
1149 	hci_conn_hold(conn);
1150 	return conn;
1151 }
1152 
1153 struct hci_conn *hci_connect_acl(struct hci_dev *hdev, bdaddr_t *dst,
1154 				 u8 sec_level, u8 auth_type,
1155 				 enum conn_reasons conn_reason)
1156 {
1157 	struct hci_conn *acl;
1158 
1159 	if (!hci_dev_test_flag(hdev, HCI_BREDR_ENABLED)) {
1160 		if (lmp_bredr_capable(hdev))
1161 			return ERR_PTR(-ECONNREFUSED);
1162 
1163 		return ERR_PTR(-EOPNOTSUPP);
1164 	}
1165 
1166 	acl = hci_conn_hash_lookup_ba(hdev, ACL_LINK, dst);
1167 	if (!acl) {
1168 		acl = hci_conn_add(hdev, ACL_LINK, dst, HCI_ROLE_MASTER);
1169 		if (!acl)
1170 			return ERR_PTR(-ENOMEM);
1171 	}
1172 
1173 	hci_conn_hold(acl);
1174 
1175 	acl->conn_reason = conn_reason;
1176 	if (acl->state == BT_OPEN || acl->state == BT_CLOSED) {
1177 		acl->sec_level = BT_SECURITY_LOW;
1178 		acl->pending_sec_level = sec_level;
1179 		acl->auth_type = auth_type;
1180 		hci_acl_create_connection(acl);
1181 	}
1182 
1183 	return acl;
1184 }
1185 
1186 struct hci_conn *hci_connect_sco(struct hci_dev *hdev, int type, bdaddr_t *dst,
1187 				 __u16 setting, struct bt_codec *codec)
1188 {
1189 	struct hci_conn *acl;
1190 	struct hci_conn *sco;
1191 
1192 	acl = hci_connect_acl(hdev, dst, BT_SECURITY_LOW, HCI_AT_NO_BONDING,
1193 			      CONN_REASON_SCO_CONNECT);
1194 	if (IS_ERR(acl))
1195 		return acl;
1196 
1197 	sco = hci_conn_hash_lookup_ba(hdev, type, dst);
1198 	if (!sco) {
1199 		sco = hci_conn_add(hdev, type, dst, HCI_ROLE_MASTER);
1200 		if (!sco) {
1201 			hci_conn_drop(acl);
1202 			return ERR_PTR(-ENOMEM);
1203 		}
1204 	}
1205 
1206 	acl->link = sco;
1207 	sco->link = acl;
1208 
1209 	hci_conn_hold(sco);
1210 
1211 	sco->setting = setting;
1212 	sco->codec = *codec;
1213 
1214 	if (acl->state == BT_CONNECTED &&
1215 	    (sco->state == BT_OPEN || sco->state == BT_CLOSED)) {
1216 		set_bit(HCI_CONN_POWER_SAVE, &acl->flags);
1217 		hci_conn_enter_active_mode(acl, BT_POWER_FORCE_ACTIVE_ON);
1218 
1219 		if (test_bit(HCI_CONN_MODE_CHANGE_PEND, &acl->flags)) {
1220 			/* defer SCO setup until mode change completed */
1221 			set_bit(HCI_CONN_SCO_SETUP_PEND, &acl->flags);
1222 			return sco;
1223 		}
1224 
1225 		hci_sco_setup(acl, 0x00);
1226 	}
1227 
1228 	return sco;
1229 }
1230 
1231 /* Check link security requirement */
1232 int hci_conn_check_link_mode(struct hci_conn *conn)
1233 {
1234 	BT_DBG("hcon %p", conn);
1235 
1236 	/* In Secure Connections Only mode, it is required that Secure
1237 	 * Connections is used and the link is encrypted with AES-CCM
1238 	 * using a P-256 authenticated combination key.
1239 	 */
1240 	if (hci_dev_test_flag(conn->hdev, HCI_SC_ONLY)) {
1241 		if (!hci_conn_sc_enabled(conn) ||
1242 		    !test_bit(HCI_CONN_AES_CCM, &conn->flags) ||
1243 		    conn->key_type != HCI_LK_AUTH_COMBINATION_P256)
1244 			return 0;
1245 	}
1246 
1247 	 /* AES encryption is required for Level 4:
1248 	  *
1249 	  * BLUETOOTH CORE SPECIFICATION Version 5.2 | Vol 3, Part C
1250 	  * page 1319:
1251 	  *
1252 	  * 128-bit equivalent strength for link and encryption keys
1253 	  * required using FIPS approved algorithms (E0 not allowed,
1254 	  * SAFER+ not allowed, and P-192 not allowed; encryption key
1255 	  * not shortened)
1256 	  */
1257 	if (conn->sec_level == BT_SECURITY_FIPS &&
1258 	    !test_bit(HCI_CONN_AES_CCM, &conn->flags)) {
1259 		bt_dev_err(conn->hdev,
1260 			   "Invalid security: Missing AES-CCM usage");
1261 		return 0;
1262 	}
1263 
1264 	if (hci_conn_ssp_enabled(conn) &&
1265 	    !test_bit(HCI_CONN_ENCRYPT, &conn->flags))
1266 		return 0;
1267 
1268 	return 1;
1269 }
1270 
1271 /* Authenticate remote device */
1272 static int hci_conn_auth(struct hci_conn *conn, __u8 sec_level, __u8 auth_type)
1273 {
1274 	BT_DBG("hcon %p", conn);
1275 
1276 	if (conn->pending_sec_level > sec_level)
1277 		sec_level = conn->pending_sec_level;
1278 
1279 	if (sec_level > conn->sec_level)
1280 		conn->pending_sec_level = sec_level;
1281 	else if (test_bit(HCI_CONN_AUTH, &conn->flags))
1282 		return 1;
1283 
1284 	/* Make sure we preserve an existing MITM requirement*/
1285 	auth_type |= (conn->auth_type & 0x01);
1286 
1287 	conn->auth_type = auth_type;
1288 
1289 	if (!test_and_set_bit(HCI_CONN_AUTH_PEND, &conn->flags)) {
1290 		struct hci_cp_auth_requested cp;
1291 
1292 		cp.handle = cpu_to_le16(conn->handle);
1293 		hci_send_cmd(conn->hdev, HCI_OP_AUTH_REQUESTED,
1294 			     sizeof(cp), &cp);
1295 
1296 		/* If we're already encrypted set the REAUTH_PEND flag,
1297 		 * otherwise set the ENCRYPT_PEND.
1298 		 */
1299 		if (test_bit(HCI_CONN_ENCRYPT, &conn->flags))
1300 			set_bit(HCI_CONN_REAUTH_PEND, &conn->flags);
1301 		else
1302 			set_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags);
1303 	}
1304 
1305 	return 0;
1306 }
1307 
1308 /* Encrypt the link */
1309 static void hci_conn_encrypt(struct hci_conn *conn)
1310 {
1311 	BT_DBG("hcon %p", conn);
1312 
1313 	if (!test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags)) {
1314 		struct hci_cp_set_conn_encrypt cp;
1315 		cp.handle  = cpu_to_le16(conn->handle);
1316 		cp.encrypt = 0x01;
1317 		hci_send_cmd(conn->hdev, HCI_OP_SET_CONN_ENCRYPT, sizeof(cp),
1318 			     &cp);
1319 	}
1320 }
1321 
1322 /* Enable security */
1323 int hci_conn_security(struct hci_conn *conn, __u8 sec_level, __u8 auth_type,
1324 		      bool initiator)
1325 {
1326 	BT_DBG("hcon %p", conn);
1327 
1328 	if (conn->type == LE_LINK)
1329 		return smp_conn_security(conn, sec_level);
1330 
1331 	/* For sdp we don't need the link key. */
1332 	if (sec_level == BT_SECURITY_SDP)
1333 		return 1;
1334 
1335 	/* For non 2.1 devices and low security level we don't need the link
1336 	   key. */
1337 	if (sec_level == BT_SECURITY_LOW && !hci_conn_ssp_enabled(conn))
1338 		return 1;
1339 
1340 	/* For other security levels we need the link key. */
1341 	if (!test_bit(HCI_CONN_AUTH, &conn->flags))
1342 		goto auth;
1343 
1344 	/* An authenticated FIPS approved combination key has sufficient
1345 	 * security for security level 4. */
1346 	if (conn->key_type == HCI_LK_AUTH_COMBINATION_P256 &&
1347 	    sec_level == BT_SECURITY_FIPS)
1348 		goto encrypt;
1349 
1350 	/* An authenticated combination key has sufficient security for
1351 	   security level 3. */
1352 	if ((conn->key_type == HCI_LK_AUTH_COMBINATION_P192 ||
1353 	     conn->key_type == HCI_LK_AUTH_COMBINATION_P256) &&
1354 	    sec_level == BT_SECURITY_HIGH)
1355 		goto encrypt;
1356 
1357 	/* An unauthenticated combination key has sufficient security for
1358 	   security level 1 and 2. */
1359 	if ((conn->key_type == HCI_LK_UNAUTH_COMBINATION_P192 ||
1360 	     conn->key_type == HCI_LK_UNAUTH_COMBINATION_P256) &&
1361 	    (sec_level == BT_SECURITY_MEDIUM || sec_level == BT_SECURITY_LOW))
1362 		goto encrypt;
1363 
1364 	/* A combination key has always sufficient security for the security
1365 	   levels 1 or 2. High security level requires the combination key
1366 	   is generated using maximum PIN code length (16).
1367 	   For pre 2.1 units. */
1368 	if (conn->key_type == HCI_LK_COMBINATION &&
1369 	    (sec_level == BT_SECURITY_MEDIUM || sec_level == BT_SECURITY_LOW ||
1370 	     conn->pin_length == 16))
1371 		goto encrypt;
1372 
1373 auth:
1374 	if (test_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags))
1375 		return 0;
1376 
1377 	if (initiator)
1378 		set_bit(HCI_CONN_AUTH_INITIATOR, &conn->flags);
1379 
1380 	if (!hci_conn_auth(conn, sec_level, auth_type))
1381 		return 0;
1382 
1383 encrypt:
1384 	if (test_bit(HCI_CONN_ENCRYPT, &conn->flags)) {
1385 		/* Ensure that the encryption key size has been read,
1386 		 * otherwise stall the upper layer responses.
1387 		 */
1388 		if (!conn->enc_key_size)
1389 			return 0;
1390 
1391 		/* Nothing else needed, all requirements are met */
1392 		return 1;
1393 	}
1394 
1395 	hci_conn_encrypt(conn);
1396 	return 0;
1397 }
1398 EXPORT_SYMBOL(hci_conn_security);
1399 
1400 /* Check secure link requirement */
1401 int hci_conn_check_secure(struct hci_conn *conn, __u8 sec_level)
1402 {
1403 	BT_DBG("hcon %p", conn);
1404 
1405 	/* Accept if non-secure or higher security level is required */
1406 	if (sec_level != BT_SECURITY_HIGH && sec_level != BT_SECURITY_FIPS)
1407 		return 1;
1408 
1409 	/* Accept if secure or higher security level is already present */
1410 	if (conn->sec_level == BT_SECURITY_HIGH ||
1411 	    conn->sec_level == BT_SECURITY_FIPS)
1412 		return 1;
1413 
1414 	/* Reject not secure link */
1415 	return 0;
1416 }
1417 EXPORT_SYMBOL(hci_conn_check_secure);
1418 
1419 /* Switch role */
1420 int hci_conn_switch_role(struct hci_conn *conn, __u8 role)
1421 {
1422 	BT_DBG("hcon %p", conn);
1423 
1424 	if (role == conn->role)
1425 		return 1;
1426 
1427 	if (!test_and_set_bit(HCI_CONN_RSWITCH_PEND, &conn->flags)) {
1428 		struct hci_cp_switch_role cp;
1429 		bacpy(&cp.bdaddr, &conn->dst);
1430 		cp.role = role;
1431 		hci_send_cmd(conn->hdev, HCI_OP_SWITCH_ROLE, sizeof(cp), &cp);
1432 	}
1433 
1434 	return 0;
1435 }
1436 EXPORT_SYMBOL(hci_conn_switch_role);
1437 
1438 /* Enter active mode */
1439 void hci_conn_enter_active_mode(struct hci_conn *conn, __u8 force_active)
1440 {
1441 	struct hci_dev *hdev = conn->hdev;
1442 
1443 	BT_DBG("hcon %p mode %d", conn, conn->mode);
1444 
1445 	if (conn->mode != HCI_CM_SNIFF)
1446 		goto timer;
1447 
1448 	if (!test_bit(HCI_CONN_POWER_SAVE, &conn->flags) && !force_active)
1449 		goto timer;
1450 
1451 	if (!test_and_set_bit(HCI_CONN_MODE_CHANGE_PEND, &conn->flags)) {
1452 		struct hci_cp_exit_sniff_mode cp;
1453 		cp.handle = cpu_to_le16(conn->handle);
1454 		hci_send_cmd(hdev, HCI_OP_EXIT_SNIFF_MODE, sizeof(cp), &cp);
1455 	}
1456 
1457 timer:
1458 	if (hdev->idle_timeout > 0)
1459 		queue_delayed_work(hdev->workqueue, &conn->idle_work,
1460 				   msecs_to_jiffies(hdev->idle_timeout));
1461 }
1462 
1463 /* Drop all connection on the device */
1464 void hci_conn_hash_flush(struct hci_dev *hdev)
1465 {
1466 	struct hci_conn_hash *h = &hdev->conn_hash;
1467 	struct hci_conn *c, *n;
1468 
1469 	BT_DBG("hdev %s", hdev->name);
1470 
1471 	list_for_each_entry_safe(c, n, &h->list, list) {
1472 		c->state = BT_CLOSED;
1473 
1474 		hci_disconn_cfm(c, HCI_ERROR_LOCAL_HOST_TERM);
1475 		hci_conn_del(c);
1476 	}
1477 }
1478 
1479 /* Check pending connect attempts */
1480 void hci_conn_check_pending(struct hci_dev *hdev)
1481 {
1482 	struct hci_conn *conn;
1483 
1484 	BT_DBG("hdev %s", hdev->name);
1485 
1486 	hci_dev_lock(hdev);
1487 
1488 	conn = hci_conn_hash_lookup_state(hdev, ACL_LINK, BT_CONNECT2);
1489 	if (conn)
1490 		hci_acl_create_connection(conn);
1491 
1492 	hci_dev_unlock(hdev);
1493 }
1494 
1495 static u32 get_link_mode(struct hci_conn *conn)
1496 {
1497 	u32 link_mode = 0;
1498 
1499 	if (conn->role == HCI_ROLE_MASTER)
1500 		link_mode |= HCI_LM_MASTER;
1501 
1502 	if (test_bit(HCI_CONN_ENCRYPT, &conn->flags))
1503 		link_mode |= HCI_LM_ENCRYPT;
1504 
1505 	if (test_bit(HCI_CONN_AUTH, &conn->flags))
1506 		link_mode |= HCI_LM_AUTH;
1507 
1508 	if (test_bit(HCI_CONN_SECURE, &conn->flags))
1509 		link_mode |= HCI_LM_SECURE;
1510 
1511 	if (test_bit(HCI_CONN_FIPS, &conn->flags))
1512 		link_mode |= HCI_LM_FIPS;
1513 
1514 	return link_mode;
1515 }
1516 
1517 int hci_get_conn_list(void __user *arg)
1518 {
1519 	struct hci_conn *c;
1520 	struct hci_conn_list_req req, *cl;
1521 	struct hci_conn_info *ci;
1522 	struct hci_dev *hdev;
1523 	int n = 0, size, err;
1524 
1525 	if (copy_from_user(&req, arg, sizeof(req)))
1526 		return -EFAULT;
1527 
1528 	if (!req.conn_num || req.conn_num > (PAGE_SIZE * 2) / sizeof(*ci))
1529 		return -EINVAL;
1530 
1531 	size = sizeof(req) + req.conn_num * sizeof(*ci);
1532 
1533 	cl = kmalloc(size, GFP_KERNEL);
1534 	if (!cl)
1535 		return -ENOMEM;
1536 
1537 	hdev = hci_dev_get(req.dev_id);
1538 	if (!hdev) {
1539 		kfree(cl);
1540 		return -ENODEV;
1541 	}
1542 
1543 	ci = cl->conn_info;
1544 
1545 	hci_dev_lock(hdev);
1546 	list_for_each_entry(c, &hdev->conn_hash.list, list) {
1547 		bacpy(&(ci + n)->bdaddr, &c->dst);
1548 		(ci + n)->handle = c->handle;
1549 		(ci + n)->type  = c->type;
1550 		(ci + n)->out   = c->out;
1551 		(ci + n)->state = c->state;
1552 		(ci + n)->link_mode = get_link_mode(c);
1553 		if (++n >= req.conn_num)
1554 			break;
1555 	}
1556 	hci_dev_unlock(hdev);
1557 
1558 	cl->dev_id = hdev->id;
1559 	cl->conn_num = n;
1560 	size = sizeof(req) + n * sizeof(*ci);
1561 
1562 	hci_dev_put(hdev);
1563 
1564 	err = copy_to_user(arg, cl, size);
1565 	kfree(cl);
1566 
1567 	return err ? -EFAULT : 0;
1568 }
1569 
1570 int hci_get_conn_info(struct hci_dev *hdev, void __user *arg)
1571 {
1572 	struct hci_conn_info_req req;
1573 	struct hci_conn_info ci;
1574 	struct hci_conn *conn;
1575 	char __user *ptr = arg + sizeof(req);
1576 
1577 	if (copy_from_user(&req, arg, sizeof(req)))
1578 		return -EFAULT;
1579 
1580 	hci_dev_lock(hdev);
1581 	conn = hci_conn_hash_lookup_ba(hdev, req.type, &req.bdaddr);
1582 	if (conn) {
1583 		bacpy(&ci.bdaddr, &conn->dst);
1584 		ci.handle = conn->handle;
1585 		ci.type  = conn->type;
1586 		ci.out   = conn->out;
1587 		ci.state = conn->state;
1588 		ci.link_mode = get_link_mode(conn);
1589 	}
1590 	hci_dev_unlock(hdev);
1591 
1592 	if (!conn)
1593 		return -ENOENT;
1594 
1595 	return copy_to_user(ptr, &ci, sizeof(ci)) ? -EFAULT : 0;
1596 }
1597 
1598 int hci_get_auth_info(struct hci_dev *hdev, void __user *arg)
1599 {
1600 	struct hci_auth_info_req req;
1601 	struct hci_conn *conn;
1602 
1603 	if (copy_from_user(&req, arg, sizeof(req)))
1604 		return -EFAULT;
1605 
1606 	hci_dev_lock(hdev);
1607 	conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, &req.bdaddr);
1608 	if (conn)
1609 		req.type = conn->auth_type;
1610 	hci_dev_unlock(hdev);
1611 
1612 	if (!conn)
1613 		return -ENOENT;
1614 
1615 	return copy_to_user(arg, &req, sizeof(req)) ? -EFAULT : 0;
1616 }
1617 
1618 struct hci_chan *hci_chan_create(struct hci_conn *conn)
1619 {
1620 	struct hci_dev *hdev = conn->hdev;
1621 	struct hci_chan *chan;
1622 
1623 	BT_DBG("%s hcon %p", hdev->name, conn);
1624 
1625 	if (test_bit(HCI_CONN_DROP, &conn->flags)) {
1626 		BT_DBG("Refusing to create new hci_chan");
1627 		return NULL;
1628 	}
1629 
1630 	chan = kzalloc(sizeof(*chan), GFP_KERNEL);
1631 	if (!chan)
1632 		return NULL;
1633 
1634 	chan->conn = hci_conn_get(conn);
1635 	skb_queue_head_init(&chan->data_q);
1636 	chan->state = BT_CONNECTED;
1637 
1638 	list_add_rcu(&chan->list, &conn->chan_list);
1639 
1640 	return chan;
1641 }
1642 
1643 void hci_chan_del(struct hci_chan *chan)
1644 {
1645 	struct hci_conn *conn = chan->conn;
1646 	struct hci_dev *hdev = conn->hdev;
1647 
1648 	BT_DBG("%s hcon %p chan %p", hdev->name, conn, chan);
1649 
1650 	list_del_rcu(&chan->list);
1651 
1652 	synchronize_rcu();
1653 
1654 	/* Prevent new hci_chan's to be created for this hci_conn */
1655 	set_bit(HCI_CONN_DROP, &conn->flags);
1656 
1657 	hci_conn_put(conn);
1658 
1659 	skb_queue_purge(&chan->data_q);
1660 	kfree(chan);
1661 }
1662 
1663 void hci_chan_list_flush(struct hci_conn *conn)
1664 {
1665 	struct hci_chan *chan, *n;
1666 
1667 	BT_DBG("hcon %p", conn);
1668 
1669 	list_for_each_entry_safe(chan, n, &conn->chan_list, list)
1670 		hci_chan_del(chan);
1671 }
1672 
1673 static struct hci_chan *__hci_chan_lookup_handle(struct hci_conn *hcon,
1674 						 __u16 handle)
1675 {
1676 	struct hci_chan *hchan;
1677 
1678 	list_for_each_entry(hchan, &hcon->chan_list, list) {
1679 		if (hchan->handle == handle)
1680 			return hchan;
1681 	}
1682 
1683 	return NULL;
1684 }
1685 
1686 struct hci_chan *hci_chan_lookup_handle(struct hci_dev *hdev, __u16 handle)
1687 {
1688 	struct hci_conn_hash *h = &hdev->conn_hash;
1689 	struct hci_conn *hcon;
1690 	struct hci_chan *hchan = NULL;
1691 
1692 	rcu_read_lock();
1693 
1694 	list_for_each_entry_rcu(hcon, &h->list, list) {
1695 		hchan = __hci_chan_lookup_handle(hcon, handle);
1696 		if (hchan)
1697 			break;
1698 	}
1699 
1700 	rcu_read_unlock();
1701 
1702 	return hchan;
1703 }
1704 
1705 u32 hci_conn_get_phy(struct hci_conn *conn)
1706 {
1707 	u32 phys = 0;
1708 
1709 	/* BLUETOOTH CORE SPECIFICATION Version 5.2 | Vol 2, Part B page 471:
1710 	 * Table 6.2: Packets defined for synchronous, asynchronous, and
1711 	 * CPB logical transport types.
1712 	 */
1713 	switch (conn->type) {
1714 	case SCO_LINK:
1715 		/* SCO logical transport (1 Mb/s):
1716 		 * HV1, HV2, HV3 and DV.
1717 		 */
1718 		phys |= BT_PHY_BR_1M_1SLOT;
1719 
1720 		break;
1721 
1722 	case ACL_LINK:
1723 		/* ACL logical transport (1 Mb/s) ptt=0:
1724 		 * DH1, DM3, DH3, DM5 and DH5.
1725 		 */
1726 		phys |= BT_PHY_BR_1M_1SLOT;
1727 
1728 		if (conn->pkt_type & (HCI_DM3 | HCI_DH3))
1729 			phys |= BT_PHY_BR_1M_3SLOT;
1730 
1731 		if (conn->pkt_type & (HCI_DM5 | HCI_DH5))
1732 			phys |= BT_PHY_BR_1M_5SLOT;
1733 
1734 		/* ACL logical transport (2 Mb/s) ptt=1:
1735 		 * 2-DH1, 2-DH3 and 2-DH5.
1736 		 */
1737 		if (!(conn->pkt_type & HCI_2DH1))
1738 			phys |= BT_PHY_EDR_2M_1SLOT;
1739 
1740 		if (!(conn->pkt_type & HCI_2DH3))
1741 			phys |= BT_PHY_EDR_2M_3SLOT;
1742 
1743 		if (!(conn->pkt_type & HCI_2DH5))
1744 			phys |= BT_PHY_EDR_2M_5SLOT;
1745 
1746 		/* ACL logical transport (3 Mb/s) ptt=1:
1747 		 * 3-DH1, 3-DH3 and 3-DH5.
1748 		 */
1749 		if (!(conn->pkt_type & HCI_3DH1))
1750 			phys |= BT_PHY_EDR_3M_1SLOT;
1751 
1752 		if (!(conn->pkt_type & HCI_3DH3))
1753 			phys |= BT_PHY_EDR_3M_3SLOT;
1754 
1755 		if (!(conn->pkt_type & HCI_3DH5))
1756 			phys |= BT_PHY_EDR_3M_5SLOT;
1757 
1758 		break;
1759 
1760 	case ESCO_LINK:
1761 		/* eSCO logical transport (1 Mb/s): EV3, EV4 and EV5 */
1762 		phys |= BT_PHY_BR_1M_1SLOT;
1763 
1764 		if (!(conn->pkt_type & (ESCO_EV4 | ESCO_EV5)))
1765 			phys |= BT_PHY_BR_1M_3SLOT;
1766 
1767 		/* eSCO logical transport (2 Mb/s): 2-EV3, 2-EV5 */
1768 		if (!(conn->pkt_type & ESCO_2EV3))
1769 			phys |= BT_PHY_EDR_2M_1SLOT;
1770 
1771 		if (!(conn->pkt_type & ESCO_2EV5))
1772 			phys |= BT_PHY_EDR_2M_3SLOT;
1773 
1774 		/* eSCO logical transport (3 Mb/s): 3-EV3, 3-EV5 */
1775 		if (!(conn->pkt_type & ESCO_3EV3))
1776 			phys |= BT_PHY_EDR_3M_1SLOT;
1777 
1778 		if (!(conn->pkt_type & ESCO_3EV5))
1779 			phys |= BT_PHY_EDR_3M_3SLOT;
1780 
1781 		break;
1782 
1783 	case LE_LINK:
1784 		if (conn->le_tx_phy & HCI_LE_SET_PHY_1M)
1785 			phys |= BT_PHY_LE_1M_TX;
1786 
1787 		if (conn->le_rx_phy & HCI_LE_SET_PHY_1M)
1788 			phys |= BT_PHY_LE_1M_RX;
1789 
1790 		if (conn->le_tx_phy & HCI_LE_SET_PHY_2M)
1791 			phys |= BT_PHY_LE_2M_TX;
1792 
1793 		if (conn->le_rx_phy & HCI_LE_SET_PHY_2M)
1794 			phys |= BT_PHY_LE_2M_RX;
1795 
1796 		if (conn->le_tx_phy & HCI_LE_SET_PHY_CODED)
1797 			phys |= BT_PHY_LE_CODED_TX;
1798 
1799 		if (conn->le_rx_phy & HCI_LE_SET_PHY_CODED)
1800 			phys |= BT_PHY_LE_CODED_RX;
1801 
1802 		break;
1803 	}
1804 
1805 	return phys;
1806 }
1807