aboutsummaryrefslogtreecommitdiffstats
path: root/net/bluetooth/hci_conn.c
blob: e2600213cd5022c3324d856d9e973a557e12f062 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
/*
   BlueZ - Bluetooth protocol stack for Linux
   Copyright (c) 2000-2001, 2010, Code Aurora Forum. All rights reserved.

   Written 2000,2001 by Maxim Krasnyansky <maxk@qualcomm.com>

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License version 2 as
   published by the Free Software Foundation;

   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
   OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
   IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
   CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
   WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
   ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
   OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

   ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
   COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
   SOFTWARE IS DISCLAIMED.
*/

/* Bluetooth HCI connection handling. */

#include <linux/export.h>
#include <linux/debugfs.h>

#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>
#include <net/bluetooth/l2cap.h>

#include "hci_request.h"
#include "smp.h"
#include "a2mp.h"

struct sco_param {
	u16 pkt_type;
	u16 max_latency;
	u8  retrans_effort;
};

static const struct sco_param esco_param_cvsd[] = {
	{ EDR_ESCO_MASK & ~ESCO_2EV3, 0x000a,	0x01 }, /* S3 */
	{ EDR_ESCO_MASK & ~ESCO_2EV3, 0x0007,	0x01 }, /* S2 */
	{ EDR_ESCO_MASK | ESCO_EV3,   0x0007,	0x01 }, /* S1 */
	{ EDR_ESCO_MASK | ESCO_HV3,   0xffff,	0x01 }, /* D1 */
	{ EDR_ESCO_MASK | ESCO_HV1,   0xffff,	0x01 }, /* D0 */
};

static const struct sco_param sco_param_cvsd[] = {
	{ EDR_ESCO_MASK | ESCO_HV3,   0xffff,	0xff }, /* D1 */
	{ EDR_ESCO_MASK | ESCO_HV1,   0xffff,	0xff }, /* D0 */
};

static const struct sco_param esco_param_msbc[] = {
	{ EDR_ESCO_MASK & ~ESCO_2EV3, 0x000d,	0x02 }, /* T2 */
	{ EDR_ESCO_MASK | ESCO_EV3,   0x0008,	0x02 }, /* T1 */
};

/* This function requires the caller holds hdev->lock */
static void hci_connect_le_scan_cleanup(struct hci_conn *conn)
{
	struct hci_conn_params *params;
	struct hci_dev *hdev = conn->hdev;
	struct smp_irk *irk;
	bdaddr_t *bdaddr;
	u8 bdaddr_type;

	bdaddr = &conn->dst;
	bdaddr_type = conn->dst_type;

	/* Check if we need to convert to identity address */
	irk = hci_get_irk(hdev, bdaddr, bdaddr_type);
	if (irk) {
		bdaddr = &irk->bdaddr;
		bdaddr_type = irk->addr_type;
	}

	params = hci_pend_le_action_lookup(&hdev->pend_le_conns, bdaddr,
					   bdaddr_type);
	if (!params || !params->explicit_connect)
		return;

	/* The connection attempt was doing scan for new RPA, and is
	 * in scan phase. If params are not associated with any other
	 * autoconnect action, remove them completely. If they are, just unmark
	 * them as waiting for connection, by clearing explicit_connect field.
	 */
	params->explicit_connect = false;

	list_del_init(&params->action);

	switch (params->auto_connect) {
	case HCI_AUTO_CONN_EXPLICIT:
		hci_conn_params_del(hdev, bdaddr, bdaddr_type);
		/* return instead of break to avoid duplicate scan update */
		return;
	case HCI_AUTO_CONN_DIRECT:
	case HCI_AUTO_CONN_ALWAYS:
		list_add(&params->action, &hdev->pend_le_conns);
		break;
	case HCI_AUTO_CONN_REPORT:
		list_add(&params->action, &hdev->pend_le_reports);
		break;
	default:
		break;
	}

	hci_update_background_scan(hdev);
}

static void hci_conn_cleanup(struct hci_conn *conn)
{
	struct hci_dev *hdev = conn->hdev;

	if (test_bit(HCI_CONN_PARAM_REMOVAL_PEND, &conn->flags))
		hci_conn_params_del(conn->hdev, &conn->dst, conn->dst_type);

	hci_chan_list_flush(conn);

	hci_conn_hash_del(hdev, conn);

	if (hdev->notify)
		hdev->notify(hdev, HCI_NOTIFY_CONN_DEL);

	hci_conn_del_sysfs(conn);

	debugfs_remove_recursive(conn->debugfs);

	hci_dev_put(hdev);

	hci_conn_put(conn);
}

static void le_scan_cleanup(struct work_struct *work)
{
	struct hci_conn *conn = container_of(work, struct hci_conn,
					     le_scan_cleanup);
	struct hci_dev *hdev = conn->hdev;
	struct hci_conn *c = NULL;

	BT_DBG("%s hcon %p", hdev->name, conn);

	hci_dev_lock(hdev);

	/* Check that the hci_conn is still around */
	rcu_read_lock();
	list_for_each_entry_rcu(c, &hdev->conn_hash.list, list) {
		if (c == conn)
			break;
	}
	rcu_read_unlock();

	if (c == conn) {
		hci_connect_le_scan_cleanup(conn);
		hci_conn_cleanup(conn);
	}

	hci_dev_unlock(hdev);
	hci_dev_put(hdev);
	hci_conn_put(conn);
}

static void hci_connect_le_scan_remove(struct hci_conn *conn)
{
	BT_DBG("%s hcon %p", conn->hdev->name, conn);

	/* We can't call hci_conn_del/hci_conn_cleanup here since that
	 * could deadlock with another hci_conn_del() call that's holding
	 * hci_dev_lock and doing cancel_delayed_work_sync(&conn->disc_work).
	 * Instead, grab temporary extra references to the hci_dev and
	 * hci_conn and perform the necessary cleanup in a separate work
	 * callback.
	 */

	hci_dev_hold(conn->hdev);
	hci_conn_get(conn);

	/* Even though we hold a reference to the hdev, many other
	 * things might get cleaned up meanwhile, including the hdev's
	 * own workqueue, so we can't use that for scheduling.
	 */
	schedule_work(&conn->le_scan_cleanup);
}

static void hci_acl_create_connection(struct hci_conn *conn)
{
	struct hci_dev *hdev = conn->hdev;
	struct inquiry_entry *ie;
	struct hci_cp_create_conn cp;

	BT_DBG("hcon %p", conn);

	conn->state = BT_CONNECT;
	conn->out = true;
	conn->role = HCI_ROLE_MASTER;

	conn->attempt++;

	conn->link_policy = hdev->link_policy;

	memset(&cp, 0, sizeof(cp));
	bacpy(&cp.bdaddr, &conn->dst);
	cp.pscan_rep_mode = 0x02;

	ie = hci_inquiry_cache_lookup(hdev, &conn->dst);
	if (ie) {
		if (inquiry_entry_age(ie) <= INQUIRY_ENTRY_AGE_MAX) {
			cp.pscan_rep_mode = ie->data.pscan_rep_mode;
			cp.pscan_mode     = ie->data.pscan_mode;
			cp.clock_offset   = ie->data.clock_offset |
					    cpu_to_le16(0x8000);
		}

		memcpy(conn->dev_class, ie->data.dev_class, 3);
		if (ie->data.ssp_mode > 0)
			set_bit(HCI_CONN_SSP_ENABLED, &conn->flags);
	}

	cp.pkt_type = cpu_to_le16(conn->pkt_type);
	if (lmp_rswitch_capable(hdev) && !(hdev->link_mode & HCI_LM_MASTER))
		cp.role_switch = 0x01;
	else
		cp.role_switch = 0x00;

	hci_send_cmd(hdev, HCI_OP_CREATE_CONN, sizeof(cp), &cp);
}

int hci_disconnect(struct hci_conn *conn, __u8 reason)
{
	BT_DBG("hcon %p", conn);

	/* When we are master of an established connection and it enters
	 * the disconnect timeout, then go ahead and try to read the
	 * current clock offset.  Processing of the result is done
	 * within the event handling and hci_clock_offset_evt function.
	 */
	if (conn->type == ACL_LINK && conn->role == HCI_ROLE_MASTER &&
	    (conn->state == BT_CONNECTED || conn->state == BT_CONFIG)) {
		struct hci_dev *hdev = conn->hdev;
		struct hci_cp_read_clock_offset clkoff_cp;

		clkoff_cp.handle = cpu_to_le16(conn->handle);
		hci_send_cmd(hdev, HCI_OP_READ_CLOCK_OFFSET, sizeof(clkoff_cp),
			     &clkoff_cp);
	}

	return hci_abort_conn(conn, reason);
}

static void hci_add_sco(struct hci_conn *conn, __u16 handle)
{
	struct hci_dev *hdev = conn->hdev;
	struct hci_cp_add_sco cp;

	BT_DBG("hcon %p", conn);

	conn->state = BT_CONNECT;
	conn->out = true;

	conn->attempt++;

	cp.handle   = cpu_to_le16(handle);
	cp.pkt_type = cpu_to_le16(conn->pkt_type);

	hci_send_cmd(hdev, HCI_OP_ADD_SCO, sizeof(cp), &cp);
}

bool hci_setup_sync(struct hci_conn *conn, __u16 handle)
{
	struct hci_dev *hdev = conn->hdev;
	struct hci_cp_setup_sync_conn cp;
	const struct sco_param *param;

	BT_DBG("hcon %p", conn);

	conn->state = BT_CONNECT;
	conn->out = true;

	conn->attempt++;

	cp.handle   = cpu_to_le16(handle);

	cp.tx_bandwidth   = cpu_to_le32(0x00001f40);
	cp.rx_bandwidth   = cpu_to_le32(0x00001f40);
	cp.voice_setting  = cpu_to_le16(conn->setting);

	switch (conn->setting & SCO_AIRMODE_MASK) {
	case SCO_AIRMODE_TRANSP:
		if (conn->attempt > ARRAY_SIZE(esco_param_msbc))
			return false;
		param = &esco_param_msbc[conn->attempt - 1];
		break;
	case SCO_AIRMODE_CVSD:
		if (lmp_esco_capable(conn->link)) {
			if (conn->attempt > ARRAY_SIZE(esco_param_cvsd))
				return false;
			param = &esco_param_cvsd[conn->attempt - 1];
		} else {
			if (conn->attempt > ARRAY_SIZE(sco_param_cvsd))
				return false;
			param = &sco_param_cvsd[conn->attempt - 1];
		}
		break;
	default:
		return false;
	}

	cp.retrans_effort = param->retrans_effort;
	cp.pkt_type = __cpu_to_le16(param->pkt_type);
	cp.max_latency = __cpu_to_le16(param->max_latency);

	if (hci_send_cmd(hdev, HCI_OP_SETUP_SYNC_CONN, sizeof(cp), &cp) < 0)
		return false;

	return true;
}

u8 hci_le_conn_update(struct hci_conn *conn, u16 min, u16 max, u16 latency,
		      u16 to_multiplier)
{
	struct hci_dev *hdev = conn->hdev;
	struct hci_conn_params *params;
	struct hci_cp_le_conn_update cp;

	hci_dev_lock(hdev);

	params = hci_conn_params_lookup(hdev, &conn->dst, conn->dst_type);
	if (params) {
		params->conn_min_interval = min;
		params->conn_max_interval = max;
		params->conn_latency = latency;
		params->supervision_timeout = to_multiplier;
	}

	hci_dev_unlock(hdev);

	memset(&cp, 0, sizeof(cp));
	cp.handle		= cpu_to_le16(conn->handle);
	cp.conn_interval_min	= cpu_to_le16(min);
	cp.conn_interval_max	= cpu_to_le16(max);
	cp.conn_latency		= cpu_to_le16(latency);
	cp.supervision_timeout	= cpu_to_le16(to_multiplier);
	cp.min_ce_len		= cpu_to_le16(0x0000);
	cp.max_ce_len		= cpu_to_le16(0x0000);

	hci_send_cmd(hdev, HCI_OP_LE_CONN_UPDATE, sizeof(cp), &cp);

	if (params)
		return 0x01;

	return 0x00;
}

void hci_le_start_enc(struct hci_conn *conn, __le16 ediv, __le64 rand,
		      __u8 ltk[16], __u8 key_size)
{
	struct hci_dev *hdev = conn->hdev;
	struct hci_cp_le_start_enc cp;

	BT_DBG("hcon %p", conn);

	memset(&cp, 0, sizeof(cp));

	cp.handle = cpu_to_le16(conn->handle);
	cp.rand = rand;
	cp.ediv = ediv;
	memcpy(cp.ltk, ltk, key_size);

	hci_send_cmd(hdev, HCI_OP_LE_START_ENC, sizeof(cp), &cp);
}

/* Device _must_ be locked */
void hci_sco_setup(struct hci_conn *conn, __u8 status)
{
	struct hci_conn *sco = conn->link;

	if (!sco)
		return;

	BT_DBG("hcon %p", conn);

	if (!status) {
		if (lmp_esco_capable(conn->hdev))
			hci_setup_sync(sco, conn->handle);
		else
			hci_add_sco(sco, conn->handle);
	} else {
		hci_connect_cfm(sco, status);
		hci_conn_del(sco);
	}
}

static void hci_conn_timeout(struct work_struct *work)
{
	struct hci_conn *conn = container_of(work, struct hci_conn,
					     disc_work.work);
	int refcnt = atomic_read(&conn->refcnt);

	BT_DBG("hcon %p state %s", conn, state_to_string(conn->state));

	WARN_ON(refcnt < 0);

	/* FIXME: It was observed that in pairing failed scenario, refcnt
	 * drops below 0. Probably this is because l2cap_conn_del calls
	 * l2cap_chan_del for each channel, and inside l2cap_chan_del conn is
	 * dropped. After that loop hci_chan_del is called which also drops
	 * conn. For now make sure that ACL is alive if refcnt is higher then 0,
	 * otherwise drop it.
	 */
	if (refcnt > 0)
		return;

	/* LE connections in scanning state need special handling */
	if (conn->state == BT_CONNECT && conn->type == LE_LINK &&
	    test_bit(HCI_CONN_SCANNING, &conn->flags)) {
		hci_connect_le_scan_remove(conn);
		return;
	}

	hci_abort_conn(conn, hci_proto_disconn_ind(conn));
}

/* Enter sniff mode */
static void hci_conn_idle(struct work_struct *work)
{
	struct hci_conn *conn = container_of(work, struct hci_conn,
					     idle_work.work);
	struct hci_dev *hdev = conn->hdev;

	BT_DBG("hcon %p mode %d", conn, conn->mode);

	if (!lmp_sniff_capable(hdev) || !lmp_sniff_capable(conn))
		return;

	if (conn->mode != HCI_CM_ACTIVE || !(conn->link_policy & HCI_LP_SNIFF))
		return;

	if (lmp_sniffsubr_capable(hdev) && lmp_sniffsubr_capable(conn)) {
		struct hci_cp_sniff_subrate cp;
		cp.handle             = cpu_to_le16(conn->handle);
		cp.max_latency        = cpu_to_le16(0);
		cp.min_remote_timeout = cpu_to_le16(0);
		cp.min_local_timeout  = cpu_to_le16(0);
		hci_send_cmd(hdev, HCI_OP_SNIFF_SUBRATE, sizeof(cp), &cp);
	}

	if (!test_and_set_bit(HCI_CONN_MODE_CHANGE_PEND, &conn->flags)) {
		struct hci_cp_sniff_mode cp;
		cp.handle       = cpu_to_le16(conn->handle);
		cp.max_interval = cpu_to_le16(hdev->sniff_max_interval);
		cp.min_interval = cpu_to_le16(hdev->sniff_min_interval);
		cp.attempt      = cpu_to_le16(4);
		cp.timeout      = cpu_to_le16(1);
		hci_send_cmd(hdev, HCI_OP_SNIFF_MODE, sizeof(cp), &cp);
	}
}

static void hci_conn_auto_accept(struct work_struct *work)
{
	struct hci_conn *conn = container_of(work, struct hci_conn,
					     auto_accept_work.work);

	hci_send_cmd(conn->hdev, HCI_OP_USER_CONFIRM_REPLY, sizeof(conn->dst),
		     &conn->dst);
}

static void le_conn_timeout(struct work_struct *work)
{
	struct hci_conn *conn = container_of(work, struct hci_conn,
					     le_conn_timeout.work);
	struct hci_dev *hdev = conn->hdev;

	BT_DBG("");

	/* We could end up here due to having done directed advertising,
	 * so clean up the state if necessary. This should however only
	 * happen with broken hardware or if low duty cycle was used
	 * (which doesn't have a timeout of its own).
	 */
	if (conn->role == HCI_ROLE_SLAVE) {
		u8 enable = 0x00;
		hci_send_cmd(hdev, HCI_OP_LE_SET_ADV_ENABLE, sizeof(enable),
			     &enable);
		hci_le_conn_failed(conn, HCI_ERROR_ADVERTISING_TIMEOUT);
		return;
	}

	hci_abort_conn(conn, HCI_ERROR_REMOTE_USER_TERM);
}

struct hci_conn *hci_conn_add(struct hci_dev *hdev, int type, bdaddr_t *dst,
			      u8 role)
{
	struct hci_conn *conn;

	BT_DBG("%s dst %pMR", hdev->name, dst);

	conn = kzalloc(sizeof(*conn), GFP_KERNEL);
	if (!conn)
		return NULL;

	bacpy(&conn->dst, dst);
	bacpy(&conn->src, &hdev->bdaddr);
	conn->hdev  = hdev;
	conn->type  = type;
	conn->role  = role;
	conn->mode  = HCI_CM_ACTIVE;
	conn->state = BT_OPEN;
	conn->auth_type = HCI_AT_GENERAL_BONDING;
	conn->io_capability = hdev->io_capability;
	conn->remote_auth = 0xff;
	conn->key_type = 0xff;
	conn->rssi = HCI_RSSI_INVALID;
	conn->tx_power = HCI_TX_POWER_INVALID;
	conn->max_tx_power = HCI_TX_POWER_INVALID;

	set_bit(HCI_CONN_POWER_SAVE, &conn->flags);
	conn->disc_timeout = HCI_DISCONN_TIMEOUT;

	if (conn->role == HCI_ROLE_MASTER)
		conn->out = true;

	switch (type) {
	case ACL_LINK:
		conn->pkt_type = hdev->pkt_type & ACL_PTYPE_MASK;
		break;
	case LE_LINK:
		/* conn->src should reflect the local identity address */
		hci_copy_identity_address(hdev, &conn->src, &conn->src_type);
		break;
	case SCO_LINK:
		if (lmp_esco_capable(hdev))
			conn->pkt_type = (hdev->esco_type & SCO_ESCO_MASK) |
					(hdev->esco_type & EDR_ESCO_MASK);
		else
			conn->pkt_type = hdev->pkt_type & SCO_PTYPE_MASK;
		break;
	case ESCO_LINK:
		conn->pkt_type = hdev->esco_type & ~EDR_ESCO_MASK;
		break;
	}

	skb_queue_head_init(&conn->data_q);

	INIT_LIST_HEAD(&conn->chan_list);

	INIT_DELAYED_WORK(&conn->disc_work, hci_conn_timeout);
	INIT_DELAYED_WORK(&conn->auto_accept_work, hci_conn_auto_accept);
	INIT_DELAYED_WORK(&conn->idle_work, hci_conn_idle);
	INIT_DELAYED_WORK(&conn->le_conn_timeout, le_conn_timeout);
	INIT_WORK(&conn->le_scan_cleanup, le_scan_cleanup);

	atomic_set(&conn->refcnt, 0);

	hci_dev_hold(hdev);

	hci_conn_hash_add(hdev, conn);
	if (hdev->notify)
		hdev->notify(hdev, HCI_NOTIFY_CONN_ADD);

	hci_conn_init_sysfs(conn);

	return conn;
}

int hci_conn_del(struct hci_conn *conn)
{
	struct hci_dev *hdev = conn->hdev;

	BT_DBG("%s hcon %p handle %d", hdev->name, conn, conn->handle);

	cancel_delayed_work_sync(&conn->disc_work);
	cancel_delayed_work_sync(&conn->auto_accept_work);
	cancel_delayed_work_sync(&conn->idle_work);

	if (conn->type == ACL_LINK) {
		struct hci_conn *sco = conn->link;
		if (sco)
			sco->link = NULL;

		/* Unacked frames */
		hdev->acl_cnt += conn->sent;
	} else if (conn->type == LE_LINK) {
		cancel_delayed_work(&conn->le_conn_timeout);

		if (hdev->le_pkts)
			hdev->le_cnt += conn->sent;
		else
			hdev->acl_cnt += conn->sent;
	} else {
		struct hci_conn *acl = conn->link;
		if (acl) {
			acl->link = NULL;
			hci_conn_drop(acl);
		}
	}

	if (conn->amp_mgr)
		amp_mgr_put(conn->amp_mgr);

	skb_queue_purge(&conn->data_q);

	/* Remove the connection from the list and cleanup its remaining
	 * state. This is a separate function since for some cases like
	 * BT_CONNECT_SCAN we *only* want the cleanup part without the
	 * rest of hci_conn_del.
	 */
	hci_conn_cleanup(conn);

	return 0;
}

struct hci_dev *hci_get_route(bdaddr_t *dst, bdaddr_t *src)
{
	int use_src = bacmp(src, BDADDR_ANY);
	struct hci_dev *hdev = NULL, *d;

	BT_DBG("%pMR -> %pMR", src, dst);

	read_lock(&hci_dev_list_lock);

	list_for_each_entry(d, &hci_dev_list, list) {
		if (!test_bit(HCI_UP, &d->flags) ||
		    hci_dev_test_flag(d, HCI_USER_CHANNEL) ||
		    d->dev_type != HCI_BREDR)
			continue;

		/* Simple routing:
		 *   No source address - find interface with bdaddr != dst
		 *   Source address    - find interface with bdaddr == src
		 */

		if (use_src) {
			if (!bacmp(&d->bdaddr, src)) {
				hdev = d; break;
			}
		} else {
			if (bacmp(&d->bdaddr, dst)) {
				hdev = d; break;
			}
		}
	}

	if (hdev)
		hdev = hci_dev_hold(hdev);

	read_unlock(&hci_dev_list_lock);
	return hdev;
}
EXPORT_SYMBOL(hci_get_route);

/* This function requires the caller holds hdev->lock */
void hci_le_conn_failed(struct hci_conn *conn, u8 status)
{
	struct hci_dev *hdev = conn->hdev;
	struct hci_conn_params *params;

	params = hci_pend_le_action_lookup(&hdev->pend_le_conns, &conn->dst,
					   conn->dst_type);
	if (params && params->conn) {
		hci_conn_drop(params->conn);
		hci_conn_put(params->conn);
		params->conn = NULL;
	}

	conn->state = BT_CLOSED;

	mgmt_connect_failed(hdev, &conn->dst, conn->type, conn->dst_type,
			    status);

	hci_connect_cfm(conn, status);

	hci_conn_del(conn);

	/* Since we may have temporarily stopped the background scanning in
	 * favor of connection establishment, we should restart it.
	 */
	hci_update_background_scan(hdev);

	/* Re-enable advertising in case this was a failed connection
	 * attempt as a peripheral.
	 */
	hci_req_reenable_advertising(hdev);
}

static void create_le_conn_complete(struct hci_dev *hdev, u8 status, u16 opcode)
{
	struct hci_conn *conn;

	hci_dev_lock(hdev);

	conn = hci_lookup_le_connect(hdev);

	if (!status) {
		hci_connect_le_scan_cleanup(conn);
		goto done;
	}

	BT_ERR("HCI request failed to create LE connection: status 0x%2.2x",
	       status);

	if (!conn)
		goto done;

	hci_le_conn_failed(conn, status);

done:
	hci_dev_unlock(hdev);
}

static void hci_req_add_le_create_conn(struct hci_request *req,
				       struct hci_conn *conn)
{
	struct hci_cp_le_create_conn cp;
	struct hci_dev *hdev = conn->hdev;
	u8 own_addr_type;

	memset(&cp, 0, sizeof(cp));

	/* Update random address, but set require_privacy to false so
	 * that we never connect with an non-resolvable address.
	 */
	if (hci_update_random_address(req, false, &own_addr_type))
		return;

	cp.scan_interval = cpu_to_le16(hdev->le_scan_interval);
	cp.scan_window = cpu_to_le16(hdev->le_scan_window);
	bacpy(&cp.peer_addr, &conn->dst);
	cp.peer_addr_type = conn->dst_type;
	cp.own_address_type = own_addr_type;
	cp.conn_interval_min = cpu_to_le16(conn->le_conn_min_interval);
	cp.conn_interval_max = cpu_to_le16(conn->le_conn_max_interval);
	cp.conn_latency = cpu_to_le16(conn->le_conn_latency);
	cp.supervision_timeout = cpu_to_le16(conn->le_supv_timeout);
	cp.min_ce_len = cpu_to_le16(0x0000);
	cp.max_ce_len = cpu_to_le16(0x0000);

	hci_req_add(req, HCI_OP_LE_CREATE_CONN, sizeof(cp), &cp);

	conn->state = BT_CONNECT;
	clear_bit(HCI_CONN_SCANNING, &conn->flags);
}

static void hci_req_directed_advertising(struct hci_request *req,
					 struct hci_conn *conn)
{
	struct hci_dev *hdev = req->hdev;
	struct hci_cp_le_set_adv_param cp;
	u8 own_addr_type;
	u8 enable;

	/* Clear the HCI_LE_ADV bit temporarily so that the
	 * hci_update_random_address knows that it's safe to go ahead
	 * and write a new random address. The flag will be set back on
	 * as soon as the SET_ADV_ENABLE HCI command completes.
	 */
	hci_dev_clear_flag(hdev, HCI_LE_ADV);

	/* Set require_privacy to false so that the remote device has a
	 * chance of identifying us.
	 */
	if (hci_update_random_address(req, false, &own_addr_type) < 0)
		return;

	memset(&cp, 0, sizeof(cp));
	cp.type = LE_ADV_DIRECT_IND;
	cp.own_address_type = own_addr_type;
	cp.direct_addr_type = conn->dst_type;
	bacpy(&cp.direct_addr, &conn->dst);
	cp.channel_map = hdev->le_adv_channel_map;

	hci_req_add(req, HCI_OP_LE_SET_ADV_PARAM, sizeof(cp), &cp);

	enable = 0x01;
	hci_req_add(req, HCI_OP_LE_SET_ADV_ENABLE, sizeof(enable), &enable);

	conn->state = BT_CONNECT;
}

struct hci_conn *hci_connect_le(struct hci_dev *hdev, bdaddr_t *dst,
				u8 dst_type, u8 sec_level, u16 conn_timeout,
				u8 role)
{
	struct hci_conn_params *params;
	struct hci_conn *conn;
	struct smp_irk *irk;
	struct hci_request req;
	int err;

	/* Let's make sure that le is enabled.*/
	if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED)) {
		if (lmp_le_capable(hdev))
			return ERR_PTR(-ECONNREFUSED);

		return ERR_PTR(-EOPNOTSUPP);
	}

	/* Since the controller supports only one LE connection attempt at a
	 * time, we return -EBUSY if there is any connection attempt running.
	 */
	if (hci_lookup_le_connect(hdev))
		return ERR_PTR(-EBUSY);

	/* If there's already a connection object but it's not in
	 * scanning state it means it must already be established, in
	 * which case we can't do anything else except report a failure
	 * to connect.
	 */
	conn = hci_conn_hash_lookup_le(hdev, dst, dst_type);
	if (conn && !test_bit(HCI_CONN_SCANNING, &conn->flags)) {
		return ERR_PTR(-EBUSY);
	}

	/* When given an identity address with existing identity
	 * resolving key, the connection needs to be established
	 * to a resolvable random address.
	 *
	 * Storing the resolvable random address is required here
	 * to handle connection failures. The address will later
	 * be resolved back into the original identity address
	 * from the connect request.
	 */
	irk = hci_find_irk_by_addr(hdev, dst, dst_type);
	if (irk && bacmp(&irk->rpa, BDADDR_ANY)) {
		dst = &irk->rpa;
		dst_type = ADDR_LE_DEV_RANDOM;
	}

	if (conn) {
		bacpy(&conn->dst, dst);
	} else {
		conn = hci_conn_add(hdev, LE_LINK, dst, role);
		if (!conn)
			return ERR_PTR(-ENOMEM);
		hci_conn_hold(conn);
		conn->pending_sec_level = sec_level;
	}

	conn->dst_type = dst_type;
	conn->sec_level = BT_SECURITY_LOW;
	conn->conn_timeout = conn_timeout;

	hci_req_init(&req, hdev);

	/* Disable advertising if we're active. For master role
	 * connections most controllers will refuse to connect if
	 * advertising is enabled, and for slave role connections we
	 * anyway have to disable it in order to start directed
	 * advertising.
	 */
	if (hci_dev_test_flag(hdev, HCI_LE_ADV)) {
		u8 enable = 0x00;
		hci_req_add(&req, HCI_OP_LE_SET_ADV_ENABLE, sizeof(enable),
			    &enable);
	}

	/* If requested to connect as slave use directed advertising */
	if (conn->role == HCI_ROLE_SLAVE) {
		/* If we're active scanning most controllers are unable
		 * to initiate advertising. Simply reject the attempt.
		 */
		if (hci_dev_test_flag(hdev, HCI_LE_SCAN) &&
		    hdev->le_scan_type == LE_SCAN_ACTIVE) {
			skb_queue_purge(&req.cmd_q);
			hci_conn_del(conn);
			return ERR_PTR(-EBUSY);
		}

		hci_req_directed_advertising(&req, conn);
		goto create_conn;
	}

	params = hci_conn_params_lookup(hdev, &conn->dst, conn->dst_type);
	if (params) {
		conn->le_conn_min_interval = params->conn_min_interval;
		conn->le_conn_max_interval = params->conn_max_interval;
		conn->le_conn_latency = params->conn_latency;
		conn->le_supv_timeout = params->supervision_timeout;
	} else {
		conn->le_conn_min_interval = hdev->le_conn_min_interval;
		conn->le_conn_max_interval = hdev->le_conn_max_interval;
		conn->le_conn_latency = hdev->le_conn_latency;
		conn->le_supv_timeout = hdev->le_supv_timeout;
	}

	/* If controller is scanning, we stop it since some controllers are
	 * not able to scan and connect at the same time. Also set the
	 * HCI_LE_SCAN_INTERRUPTED flag so that the command complete
	 * handler for scan disabling knows to set the correct discovery
	 * state.
	 */
	if (hci_dev_test_flag(hdev, HCI_LE_SCAN)) {
		hci_req_add_le_scan_disable(&req);
		hci_dev_set_flag(hdev, HCI_LE_SCAN_INTERRUPTED);
	}

	hci_req_add_le_create_conn(&req, conn);

create_conn:
	err = hci_req_run(&req, create_le_conn_complete);
	if (err) {
		hci_conn_del(conn);
		return ERR_PTR(err);
	}

	return conn;
}

static bool is_connected(struct hci_dev *hdev, bdaddr_t *addr, u8 type)
{
	struct hci_conn *conn;

	conn = hci_conn_hash_lookup_le(hdev, addr, type);
	if (!conn)
		return false;

	if (conn->state != BT_CONNECTED)
		return false;

	return true;
}

/* This function requires the caller holds hdev->lock */
static int hci_explicit_conn_params_set(struct hci_dev *hdev,
					bdaddr_t *addr, u8 addr_type)
{
	struct hci_conn_params *params;

	if (is_connected(hdev, addr, addr_type))
		return -EISCONN;

	params = hci_conn_params_lookup(hdev, addr, addr_type);
	if (!params) {
		params = hci_conn_params_add(hdev, addr, addr_type);
		if (!params)
			return -ENOMEM;

		/* If we created new params, mark them to be deleted in
		 * hci_connect_le_scan_cleanup. It's different case than
		 * existing disabled params, those will stay after cleanup.
		 */
		params->auto_connect = HCI_AUTO_CONN_EXPLICIT;
	}

	/* We're trying to connect, so make sure params are at pend_le_conns */
	if (params->auto_connect == HCI_AUTO_CONN_DISABLED ||
	    params->auto_connect == HCI_AUTO_CONN_REPORT ||
	    params->auto_connect == HCI_AUTO_CONN_EXPLICIT) {
		list_del_init(&params->action);
		list_add(&params->action, &hdev->pend_le_conns);
	}

	params->explicit_connect = true;

	BT_DBG("addr %pMR (type %u) auto_connect %u", addr, addr_type,
	       params->auto_connect);

	return 0;
}

/* This function requires the caller holds hdev->lock */
struct hci_conn *hci_connect_le_scan(struct hci_dev *hdev, bdaddr_t *dst,
				     u8 dst_type, u8 sec_level,
				     u16 conn_timeout)
{
	struct hci_conn *conn;

	/* Let's make sure that le is enabled.*/
	if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED)) {
		if (lmp_le_capable(hdev))
			return ERR_PTR(-ECONNREFUSED);

		return ERR_PTR(-EOPNOTSUPP);
	}

	/* Some devices send ATT messages as soon as the physical link is
	 * established. To be able to handle these ATT messages, the user-
	 * space first establishes the connection and then starts the pairing
	 * process.
	 *
	 * So if a hci_conn object already exists for the following connection
	 * attempt, we simply update pending_sec_level and auth_type fields
	 * and return the object found.
	 */
	conn = hci_conn_hash_lookup_le(hdev, dst, dst_type);
	if (conn) {
		if (conn->pending_sec_level < sec_level)
			conn->pending_sec_level = sec_level;
		goto done;
	}

	BT_DBG("requesting refresh of dst_addr");

	conn = hci_conn_add(hdev, LE_LINK, dst, HCI_ROLE_MASTER);
	if (!conn)
		return ERR_PTR(-ENOMEM);

	if (hci_explicit_conn_params_set(hdev, dst, dst_type) < 0)
		return ERR_PTR(-EBUSY);

	conn->state = BT_CONNECT;
	set_bit(HCI_CONN_SCANNING, &conn->flags);
	conn->dst_type = dst_type;
	conn->sec_level = BT_SECURITY_LOW;
	conn->pending_sec_level = sec_level;
	conn->conn_timeout = conn_timeout;

	hci_update_background_scan(hdev);

done:
	hci_conn_hold(conn);
	return conn;
}

struct hci_conn *hci_connect_acl(struct hci_dev *hdev, bdaddr_t *dst,
				 u8 sec_level, u8 auth_type)
{
	struct hci_conn *acl;

	if (!hci_dev_test_flag(hdev, HCI_BREDR_ENABLED)) {
		if (lmp_bredr_capable(hdev))
			return ERR_PTR(-ECONNREFUSED);

		return ERR_PTR(-EOPNOTSUPP);
	}

	acl = hci_conn_hash_lookup_ba(hdev, ACL_LINK, dst);
	if (!acl) {
		acl = hci_conn_add(hdev, ACL_LINK, dst, HCI_ROLE_MASTER);
		if (!acl)
			return ERR_PTR(-ENOMEM);
	}

	hci_conn_hold(acl);

	if (acl->state == BT_OPEN || acl->state == BT_CLOSED) {
		acl->sec_level = BT_SECURITY_LOW;
		acl->pending_sec_level = sec_level;
		acl->auth_type = auth_type;
		hci_acl_create_connection(acl);
	}

	return acl;
}

struct hci_conn *hci_connect_sco(struct hci_dev *hdev, int type, bdaddr_t *dst,
				 __u16 setting)
{
	struct hci_conn *acl;
	struct hci_conn *sco;

	acl = hci_connect_acl(hdev, dst, BT_SECURITY_LOW, HCI_AT_NO_BONDING);
	if (IS_ERR(acl))
		return acl;

	sco = hci_conn_hash_lookup_ba(hdev, type, dst);
	if (!sco) {
		sco = hci_conn_add(hdev, type, dst, HCI_ROLE_MASTER);
		if (!sco) {
			hci_conn_drop(acl);
			return ERR_PTR(-ENOMEM);
		}
	}

	acl->link = sco;
	sco->link = acl;

	hci_conn_hold(sco);

	sco->setting = setting;

	if (acl->state == BT_CONNECTED &&
	    (sco->state == BT_OPEN || sco->state == BT_CLOSED)) {
		set_bit(HCI_CONN_POWER_SAVE, &acl->flags);
		hci_conn_enter_active_mode(acl, BT_POWER_FORCE_ACTIVE_ON);

		if (test_bit(HCI_CONN_MODE_CHANGE_PEND, &acl->flags)) {
			/* defer SCO setup until mode change completed */
			set_bit(HCI_CONN_SCO_SETUP_PEND, &acl->flags);
			return sco;
		}

		hci_sco_setup(acl, 0x00);
	}

	return sco;
}

/* Check link security requirement */
int hci_conn_check_link_mode(struct hci_conn *conn)
{
	BT_DBG("hcon %p", conn);

	/* In Secure Connections Only mode, it is required that Secure
	 * Connections is used and the link is encrypted with AES-CCM
	 * using a P-256 authenticated combination key.
	 */
	if (hci_dev_test_flag(conn->hdev, HCI_SC_ONLY)) {
		if (!hci_conn_sc_enabled(conn) ||
		    !test_bit(HCI_CONN_AES_CCM, &conn->flags) ||
		    conn->key_type != HCI_LK_AUTH_COMBINATION_P256)
			return 0;
	}

	if (hci_conn_ssp_enabled(conn) &&
	    !test_bit(HCI_CONN_ENCRYPT, &conn->flags))
		return 0;

	return 1;
}

/* Authenticate remote device */
static int hci_conn_auth(struct hci_conn *conn, __u8 sec_level, __u8 auth_type)
{
	BT_DBG("hcon %p", conn);

	if (conn->pending_sec_level > sec_level)
		sec_level = conn->pending_sec_level;

	if (sec_level > conn->sec_level)
		conn->pending_sec_level = sec_level;
	else if (test_bit(HCI_CONN_AUTH, &conn->flags))
		return 1;

	/* Make sure we preserve an existing MITM requirement*/
	auth_type |= (conn->auth_type & 0x01);

	conn->auth_type = auth_type;

	if (!test_and_set_bit(HCI_CONN_AUTH_PEND, &conn->flags)) {
		struct hci_cp_auth_requested cp;

		cp.handle = cpu_to_le16(conn->handle);
		hci_send_cmd(conn->hdev, HCI_OP_AUTH_REQUESTED,
			     sizeof(cp), &cp);

		/* If we're already encrypted set the REAUTH_PEND flag,
		 * otherwise set the ENCRYPT_PEND.
		 */
		if (test_bit(HCI_CONN_ENCRYPT, &conn->flags))
			set_bit(HCI_CONN_REAUTH_PEND, &conn->flags);
		else
			set_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags);
	}

	return 0;
}

/* Encrypt the the link */
static void hci_conn_encrypt(struct hci_conn *conn)
{
	BT_DBG("hcon %p", conn);

	if (!test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags)) {
		struct hci_cp_set_conn_encrypt cp;
		cp.handle  = cpu_to_le16(conn->handle);
		cp.encrypt = 0x01;
		hci_send_cmd(conn->hdev, HCI_OP_SET_CONN_ENCRYPT, sizeof(cp),
			     &cp);
	}
}

/* Enable security */
int hci_conn_security(struct hci_conn *conn, __u8 sec_level, __u8 auth_type,
		      bool initiator)
{
	BT_DBG("hcon %p", conn);

	if (conn->type == LE_LINK)
		return smp_conn_security(conn, sec_level);

	/* For sdp we don't need the link key. */
	if (sec_level == BT_SECURITY_SDP)
		return 1;

	/* For non 2.1 devices and low security level we don't need the link
	   key. */
	if (sec_level == BT_SECURITY_LOW && !hci_conn_ssp_enabled(conn))
		return 1;

	/* For other security levels we need the link key. */
	if (!test_bit(HCI_CONN_AUTH, &conn->flags))
		goto auth;

	/* An authenticated FIPS approved combination key has sufficient
	 * security for security level 4. */
	if (conn->key_type == HCI_LK_AUTH_COMBINATION_P256 &&
	    sec_level == BT_SECURITY_FIPS)
		goto encrypt;

	/* An authenticated combination key has sufficient security for
	   security level 3. */
	if ((conn->key_type == HCI_LK_AUTH_COMBINATION_P192 ||
	     conn->key_type == HCI_LK_AUTH_COMBINATION_P256) &&
	    sec_level == BT_SECURITY_HIGH)
		goto encrypt;

	/* An unauthenticated combination key has sufficient security for
	   security level 1 and 2. */
	if ((conn->key_type == HCI_LK_UNAUTH_COMBINATION_P192 ||
	     conn->key_type == HCI_LK_UNAUTH_COMBINATION_P256) &&
	    (sec_level == BT_SECURITY_MEDIUM || sec_level == BT_SECURITY_LOW))
		goto encrypt;

	/* A combination key has always sufficient security for the security
	   levels 1 or 2. High security level requires the combination key
	   is generated using maximum PIN code length (16).
	   For pre 2.1 units. */
	if (conn->key_type == HCI_LK_COMBINATION &&
	    (sec_level == BT_SECURITY_MEDIUM || sec_level == BT_SECURITY_LOW ||
	     conn->pin_length == 16))
		goto encrypt;

auth:
	if (test_bit(HCI_CONN_ENCRYPT_PEND, &conn->flags))
		return 0;

	if (initiator)
		set_bit(HCI_CONN_AUTH_INITIATOR, &conn->flags);

	if (!hci_conn_auth(conn, sec_level, auth_type))
		return 0;

encrypt:
	if (test_bit(HCI_CONN_ENCRYPT, &conn->flags))
		return 1;

	hci_conn_encrypt(conn);
	return 0;
}
EXPORT_SYMBOL(hci_conn_security);

/* Check secure link requirement */
int hci_conn_check_secure(struct hci_conn *conn, __u8 sec_level)
{
	BT_DBG("hcon %p", conn);

	/* Accept if non-secure or higher security level is required */
	if (sec_level != BT_SECURITY_HIGH && sec_level != BT_SECURITY_FIPS)
		return 1;

	/* Accept if secure or higher security level is already present */
	if (conn->sec_level == BT_SECURITY_HIGH ||
	    conn->sec_level == BT_SECURITY_FIPS)
		return 1;

	/* Reject not secure link */
	return 0;
}
EXPORT_SYMBOL(hci_conn_check_secure);

/* Switch role */
int hci_conn_switch_role(struct hci_conn *conn, __u8 role)
{
	BT_DBG("hcon %p", conn);

	if (role == conn->role)
		return 1;

	if (!test_and_set_bit(HCI_CONN_RSWITCH_PEND, &conn->flags)) {
		struct hci_cp_switch_role cp;
		bacpy(&cp.bdaddr, &conn->dst);
		cp.role = role;
		hci_send_cmd(conn->hdev, HCI_OP_SWITCH_ROLE, sizeof(cp), &cp);
	}

	return 0;
}
EXPORT_SYMBOL(hci_conn_switch_role);

/* Enter active mode */
void hci_conn_enter_active_mode(struct hci_conn *conn, __u8 force_active)
{
	struct hci_dev *hdev = conn->hdev;

	BT_DBG("hcon %p mode %d", conn, conn->mode);

	if (conn->mode != HCI_CM_SNIFF)
		goto timer;

	if (!test_bit(HCI_CONN_POWER_SAVE, &conn->flags) && !force_active)
		goto timer;

	if (!test_and_set_bit(HCI_CONN_MODE_CHANGE_PEND, &conn->flags)) {
		struct hci_cp_exit_sniff_mode cp;
		cp.handle = cpu_to_le16(conn->handle);
		hci_send_cmd(hdev, HCI_OP_EXIT_SNIFF_MODE, sizeof(cp), &cp);
	}

timer:
	if (hdev->idle_timeout > 0)
		queue_delayed_work(hdev->workqueue, &conn->idle_work,
				   msecs_to_jiffies(hdev->idle_timeout));
}

/* Drop all connection on the device */
void hci_conn_hash_flush(struct hci_dev *hdev)
{
	struct hci_conn_hash *h = &hdev->conn_hash;
	struct hci_conn *c, *n;

	BT_DBG("hdev %s", hdev->name);

	list_for_each_entry_safe(c, n, &h->list, list) {
		c->state = BT_CLOSED;

		hci_disconn_cfm(c, HCI_ERROR_LOCAL_HOST_TERM);
		hci_conn_del(c);
	}
}

/* Check pending connect attempts */
void hci_conn_check_pending(struct hci_dev *hdev)
{
	struct hci_conn *conn;

	BT_DBG("hdev %s", hdev->name);

	hci_dev_lock(hdev);

	conn = hci_conn_hash_lookup_state(hdev, ACL_LINK, BT_CONNECT2);
	if (conn)
		hci_acl_create_connection(conn);

	hci_dev_unlock(hdev);
}

static u32 get_link_mode(struct hci_conn *conn)
{
	u32 link_mode = 0;

	if (conn->role == HCI_ROLE_MASTER)
		link_mode |= HCI_LM_MASTER;

	if (test_bit(HCI_CONN_ENCRYPT, &conn->flags))
		link_mode |= HCI_LM_ENCRYPT;

	if (test_bit(HCI_CONN_AUTH, &conn->flags))
		link_mode |= HCI_LM_AUTH;

	if (test_bit(HCI_CONN_SECURE, &conn->flags))
		link_mode |= HCI_LM_SECURE;

	if (test_bit(HCI_CONN_FIPS, &conn->flags))
		link_mode |= HCI_LM_FIPS;

	return link_mode;
}

int hci_get_conn_list(void __user *arg)
{
	struct hci_conn *c;
	struct hci_conn_list_req req, *cl;
	struct hci_conn_info *ci;
	struct hci_dev *hdev;
	int n = 0, size, err;

	if (copy_from_user(&req, arg, sizeof(req)))
		return -EFAULT;

	if (!req.conn_num || req.conn_num > (PAGE_SIZE * 2) / sizeof(*ci))
		return -EINVAL;

	size = sizeof(req) + req.conn_num * sizeof(*ci);

	cl = kmalloc(size, GFP_KERNEL);
	if (!cl)
		return -ENOMEM;

	hdev = hci_dev_get(req.dev_id);
	if (!hdev) {
		kfree(cl);
		return -ENODEV;
	}

	ci = cl->conn_info;

	hci_dev_lock(hdev);
	list_for_each_entry(c, &hdev->conn_hash.list, list) {
		bacpy(&(ci + n)->bdaddr, &c->dst);
		(ci + n)->handle = c->handle;
		(ci + n)->type  = c->type;
		(ci + n)->out   = c->out;
		(ci + n)->state = c->state;
		(ci + n)->link_mode = get_link_mode(c);
		if (++n >= req.conn_num)
			break;
	}
	hci_dev_unlock(hdev);

	cl->dev_id = hdev->id;
	cl->conn_num = n;
	size = sizeof(req) + n * sizeof(*ci);

	hci_dev_put(hdev);

	err = copy_to_user(arg, cl, size);
	kfree(cl);

	return err ? -EFAULT : 0;
}

int hci_get_conn_info(struct hci_dev *hdev, void __user *arg)
{
	struct hci_conn_info_req req;
	struct hci_conn_info ci;
	struct hci_conn *conn;
	char __user *ptr = arg + sizeof(req);

	if (copy_from_user(&req, arg, sizeof(req)))
		return -EFAULT;

	hci_dev_lock(hdev);
	conn = hci_conn_hash_lookup_ba(hdev, req.type, &req.bdaddr);
	if (conn) {
		bacpy(&ci.bdaddr, &conn->dst);
		ci.handle = conn->handle;
		ci.type  = conn->type;
		ci.out   = conn->out;
		ci.state = conn->state;
		ci.link_mode = get_link_mode(conn);
	}
	hci_dev_unlock(hdev);

	if (!conn)
		return -ENOENT;

	return copy_to_user(ptr, &ci, sizeof(ci)) ? -EFAULT : 0;
}

int hci_get_auth_info(struct hci_dev *hdev, void __user *arg)
{
	struct hci_auth_info_req req;
	struct hci_conn *conn;

	if (copy_from_user(&req, arg, sizeof(req)))
		return -EFAULT;

	hci_dev_lock(hdev);
	conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, &req.bdaddr);
	if (conn)
		req.type = conn->auth_type;
	hci_dev_unlock(hdev);

	if (!conn)
		return -ENOENT;

	return copy_to_user(arg, &req, sizeof(req)) ? -EFAULT : 0;
}

struct hci_chan *hci_chan_create(struct hci_conn *conn)
{
	struct hci_dev *hdev = conn->hdev;
	struct hci_chan *chan;

	BT_DBG("%s hcon %p", hdev->name, conn);

	if (test_bit(HCI_CONN_DROP, &conn->flags)) {
		BT_DBG("Refusing to create new hci_chan");
		return NULL;
	}

	chan = kzalloc(sizeof(*chan), GFP_KERNEL);
	if (!chan)
		return NULL;

	chan->conn = hci_conn_get(conn);
	skb_queue_head_init(&chan->data_q);
	chan->state = BT_CONNECTED;

	list_add_rcu(&chan->list, &conn->chan_list);

	return chan;
}

void hci_chan_del(struct hci_chan *chan)
{
	struct hci_conn *conn = chan->conn;
	struct hci_dev *hdev = conn->hdev;

	BT_DBG("%s hcon %p chan %p", hdev->name, conn, chan);

	list_del_rcu(&chan->list);

	synchronize_rcu();

	/* Prevent new hci_chan's to be created for this hci_conn */
	set_bit(HCI_CONN_DROP, &conn->flags);

	hci_conn_put(conn);

	skb_queue_purge(&chan->data_q);
	kfree(chan);
}

void hci_chan_list_flush(struct hci_conn *conn)
{
	struct hci_chan *chan, *n;

	BT_DBG("hcon %p", conn);

	list_for_each_entry_safe(chan, n, &conn->chan_list, list)
		hci_chan_del(chan);
}

static struct hci_chan *__hci_chan_lookup_handle(struct hci_conn *hcon,
						 __u16 handle)
{
	struct hci_chan *hchan;

	list_for_each_entry(hchan, &hcon->chan_list, list) {
		if (hchan->handle == handle)
			return hchan;
	}

	return NULL;
}

struct hci_chan *hci_chan_lookup_handle(struct hci_dev *hdev, __u16 handle)
{
	struct hci_conn_hash *h = &hdev->conn_hash;
	struct hci_conn *hcon;
	struct hci_chan *hchan = NULL;

	rcu_read_lock();

	list_for_each_entry_rcu(hcon, &h->list, list) {
		hchan = __hci_chan_lookup_handle(hcon, handle);
		if (hchan)
			break;
	}

	rcu_read_unlock();

	return hchan;
}