aboutsummaryrefslogtreecommitdiff
path: root/net/bluetooth/l2cap_sock.c
blob: a4bb27e8427e9aabaa48b90727cb23bcf5568f96 (plain)
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
/*
   BlueZ - Bluetooth protocol stack for Linux
   Copyright (C) 2000-2001 Qualcomm Incorporated
   Copyright (C) 2009-2010 Gustavo F. Padovan <gustavo@padovan.org>
   Copyright (C) 2010 Google Inc.
   Copyright (C) 2011 ProFUSION Embedded Systems

   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 L2CAP sockets. */

#include <linux/export.h>

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

static const struct proto_ops l2cap_sock_ops;
static void l2cap_sock_init(struct sock *sk, struct sock *parent);
static struct sock *l2cap_sock_alloc(struct net *net, struct socket *sock, int proto, gfp_t prio);

static int l2cap_sock_bind(struct socket *sock, struct sockaddr *addr, int alen)
{
	struct sock *sk = sock->sk;
	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
	struct sockaddr_l2 la;
	int len, err = 0;

	BT_DBG("sk %p", sk);

	if (!addr || addr->sa_family != AF_BLUETOOTH)
		return -EINVAL;

	memset(&la, 0, sizeof(la));
	len = min_t(unsigned int, sizeof(la), alen);
	memcpy(&la, addr, len);

	if (la.l2_cid && la.l2_psm)
		return -EINVAL;

	lock_sock(sk);

	if (sk->sk_state != BT_OPEN) {
		err = -EBADFD;
		goto done;
	}

	if (la.l2_psm) {
		__u16 psm = __le16_to_cpu(la.l2_psm);

		/* PSM must be odd and lsb of upper byte must be 0 */
		if ((psm & 0x0101) != 0x0001) {
			err = -EINVAL;
			goto done;
		}

		/* Restrict usage of well-known PSMs */
		if (psm < 0x1001 && !capable(CAP_NET_BIND_SERVICE)) {
			err = -EACCES;
			goto done;
		}
	}

	if (la.l2_cid)
		err = l2cap_add_scid(chan, __le16_to_cpu(la.l2_cid));
	else
		err = l2cap_add_psm(chan, &la.l2_bdaddr, la.l2_psm);

	if (err < 0)
		goto done;

	if (__le16_to_cpu(la.l2_psm) == L2CAP_PSM_SDP ||
	    __le16_to_cpu(la.l2_psm) == L2CAP_PSM_RFCOMM)
		chan->sec_level = BT_SECURITY_SDP;

	bacpy(&bt_sk(sk)->src, &la.l2_bdaddr);

	chan->state = BT_BOUND;
	sk->sk_state = BT_BOUND;

done:
	release_sock(sk);
	return err;
}

static int l2cap_sock_connect(struct socket *sock, struct sockaddr *addr, int alen, int flags)
{
	struct sock *sk = sock->sk;
	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
	struct sockaddr_l2 la;
	int len, err = 0;

	BT_DBG("sk %p", sk);

	if (!addr || alen < sizeof(addr->sa_family) ||
	    addr->sa_family != AF_BLUETOOTH)
		return -EINVAL;

	memset(&la, 0, sizeof(la));
	len = min_t(unsigned int, sizeof(la), alen);
	memcpy(&la, addr, len);

	if (la.l2_cid && la.l2_psm)
		return -EINVAL;

	err = l2cap_chan_connect(chan, la.l2_psm, __le16_to_cpu(la.l2_cid),
				 &la.l2_bdaddr, la.l2_bdaddr_type);
	if (err)
		return err;

	lock_sock(sk);

	err = bt_sock_wait_state(sk, BT_CONNECTED,
			sock_sndtimeo(sk, flags & O_NONBLOCK));

	release_sock(sk);

	return err;
}

static int l2cap_sock_listen(struct socket *sock, int backlog)
{
	struct sock *sk = sock->sk;
	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
	int err = 0;

	BT_DBG("sk %p backlog %d", sk, backlog);

	lock_sock(sk);

	if (sk->sk_state != BT_BOUND) {
		err = -EBADFD;
		goto done;
	}

	if (sk->sk_type != SOCK_SEQPACKET && sk->sk_type != SOCK_STREAM) {
		err = -EINVAL;
		goto done;
	}

	switch (chan->mode) {
	case L2CAP_MODE_BASIC:
		break;
	case L2CAP_MODE_ERTM:
	case L2CAP_MODE_STREAMING:
		if (!disable_ertm)
			break;
		/* fall through */
	default:
		err = -ENOTSUPP;
		goto done;
	}

	sk->sk_max_ack_backlog = backlog;
	sk->sk_ack_backlog = 0;

	chan->state = BT_LISTEN;
	sk->sk_state = BT_LISTEN;

done:
	release_sock(sk);
	return err;
}

static int l2cap_sock_accept(struct socket *sock, struct socket *newsock, int flags)
{
	DECLARE_WAITQUEUE(wait, current);
	struct sock *sk = sock->sk, *nsk;
	long timeo;
	int err = 0;

	lock_sock_nested(sk, SINGLE_DEPTH_NESTING);

	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);

	BT_DBG("sk %p timeo %ld", sk, timeo);

	/* Wait for an incoming connection. (wake-one). */
	add_wait_queue_exclusive(sk_sleep(sk), &wait);
	while (1) {
		set_current_state(TASK_INTERRUPTIBLE);

		if (sk->sk_state != BT_LISTEN) {
			err = -EBADFD;
			break;
		}

		nsk = bt_accept_dequeue(sk, newsock);
		if (nsk)
			break;

		if (!timeo) {
			err = -EAGAIN;
			break;
		}

		if (signal_pending(current)) {
			err = sock_intr_errno(timeo);
			break;
		}

		release_sock(sk);
		timeo = schedule_timeout(timeo);
		lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
	}
	__set_current_state(TASK_RUNNING);
	remove_wait_queue(sk_sleep(sk), &wait);

	if (err)
		goto done;

	newsock->state = SS_CONNECTED;

	BT_DBG("new socket %p", nsk);

done:
	release_sock(sk);
	return err;
}

static int l2cap_sock_getname(struct socket *sock, struct sockaddr *addr, int *len, int peer)
{
	struct sockaddr_l2 *la = (struct sockaddr_l2 *) addr;
	struct sock *sk = sock->sk;
	struct l2cap_chan *chan = l2cap_pi(sk)->chan;

	BT_DBG("sock %p, sk %p", sock, sk);

	addr->sa_family = AF_BLUETOOTH;
	*len = sizeof(struct sockaddr_l2);

	if (peer) {
		la->l2_psm = chan->psm;
		bacpy(&la->l2_bdaddr, &bt_sk(sk)->dst);
		la->l2_cid = cpu_to_le16(chan->dcid);
	} else {
		la->l2_psm = chan->sport;
		bacpy(&la->l2_bdaddr, &bt_sk(sk)->src);
		la->l2_cid = cpu_to_le16(chan->scid);
	}

	return 0;
}

static int l2cap_sock_getsockopt_old(struct socket *sock, int optname, char __user *optval, int __user *optlen)
{
	struct sock *sk = sock->sk;
	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
	struct l2cap_options opts;
	struct l2cap_conninfo cinfo;
	int len, err = 0;
	u32 opt;

	BT_DBG("sk %p", sk);

	if (get_user(len, optlen))
		return -EFAULT;

	lock_sock(sk);

	switch (optname) {
	case L2CAP_OPTIONS:
		memset(&opts, 0, sizeof(opts));
		opts.imtu     = chan->imtu;
		opts.omtu     = chan->omtu;
		opts.flush_to = chan->flush_to;
		opts.mode     = chan->mode;
		opts.fcs      = chan->fcs;
		opts.max_tx   = chan->max_tx;
		opts.txwin_size = chan->tx_win;

		len = min_t(unsigned int, len, sizeof(opts));
		if (copy_to_user(optval, (char *) &opts, len))
			err = -EFAULT;

		break;

	case L2CAP_LM:
		switch (chan->sec_level) {
		case BT_SECURITY_LOW:
			opt = L2CAP_LM_AUTH;
			break;
		case BT_SECURITY_MEDIUM:
			opt = L2CAP_LM_AUTH | L2CAP_LM_ENCRYPT;
			break;
		case BT_SECURITY_HIGH:
			opt = L2CAP_LM_AUTH | L2CAP_LM_ENCRYPT |
							L2CAP_LM_SECURE;
			break;
		default:
			opt = 0;
			break;
		}

		if (test_bit(FLAG_ROLE_SWITCH, &chan->flags))
			opt |= L2CAP_LM_MASTER;

		if (test_bit(FLAG_FORCE_RELIABLE, &chan->flags))
			opt |= L2CAP_LM_RELIABLE;

		if (put_user(opt, (u32 __user *) optval))
			err = -EFAULT;
		break;

	case L2CAP_CONNINFO:
		if (sk->sk_state != BT_CONNECTED &&
		    !(sk->sk_state == BT_CONNECT2 &&
		      test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags))) {
			err = -ENOTCONN;
			break;
		}

		memset(&cinfo, 0, sizeof(cinfo));
		cinfo.hci_handle = chan->conn->hcon->handle;
		memcpy(cinfo.dev_class, chan->conn->hcon->dev_class, 3);

		len = min_t(unsigned int, len, sizeof(cinfo));
		if (copy_to_user(optval, (char *) &cinfo, len))
			err = -EFAULT;

		break;

	default:
		err = -ENOPROTOOPT;
		break;
	}

	release_sock(sk);
	return err;
}

static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen)
{
	struct sock *sk = sock->sk;
	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
	struct bt_security sec;
	struct bt_power pwr;
	int len, err = 0;

	BT_DBG("sk %p", sk);

	if (level == SOL_L2CAP)
		return l2cap_sock_getsockopt_old(sock, optname, optval, optlen);

	if (level != SOL_BLUETOOTH)
		return -ENOPROTOOPT;

	if (get_user(len, optlen))
		return -EFAULT;

	lock_sock(sk);

	switch (optname) {
	case BT_SECURITY:
		if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED &&
					chan->chan_type != L2CAP_CHAN_RAW) {
			err = -EINVAL;
			break;
		}

		memset(&sec, 0, sizeof(sec));
		if (chan->conn)
			sec.level = chan->conn->hcon->sec_level;
		else
			sec.level = chan->sec_level;

		if (sk->sk_state == BT_CONNECTED)
			sec.key_size = chan->conn->hcon->enc_key_size;

		len = min_t(unsigned int, len, sizeof(sec));
		if (copy_to_user(optval, (char *) &sec, len))
			err = -EFAULT;

		break;

	case BT_DEFER_SETUP:
		if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
			err = -EINVAL;
			break;
		}

		if (put_user(test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags),
			     (u32 __user *) optval))
			err = -EFAULT;

		break;

	case BT_FLUSHABLE:
		if (put_user(test_bit(FLAG_FLUSHABLE, &chan->flags),
						(u32 __user *) optval))
			err = -EFAULT;

		break;

	case BT_POWER:
		if (sk->sk_type != SOCK_SEQPACKET && sk->sk_type != SOCK_STREAM
				&& sk->sk_type != SOCK_RAW) {
			err = -EINVAL;
			break;
		}

		pwr.force_active = test_bit(FLAG_FORCE_ACTIVE, &chan->flags);

		len = min_t(unsigned int, len, sizeof(pwr));
		if (copy_to_user(optval, (char *) &pwr, len))
			err = -EFAULT;

		break;

	case BT_CHANNEL_POLICY:
		if (!enable_hs) {
			err = -ENOPROTOOPT;
			break;
		}

		if (put_user(chan->chan_policy, (u32 __user *) optval))
			err = -EFAULT;
		break;

	default:
		err = -ENOPROTOOPT;
		break;
	}

	release_sock(sk);
	return err;
}

static bool l2cap_valid_mtu(struct l2cap_chan *chan, u16 mtu)
{
	switch (chan->scid) {
	case L2CAP_CID_LE_DATA:
		if (mtu < L2CAP_LE_MIN_MTU)
			return false;
		break;

	default:
		if (mtu < L2CAP_DEFAULT_MIN_MTU)
			return false;
	}

	return true;
}

static int l2cap_sock_setsockopt_old(struct socket *sock, int optname, char __user *optval, unsigned int optlen)
{
	struct sock *sk = sock->sk;
	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
	struct l2cap_options opts;
	int len, err = 0;
	u32 opt;

	BT_DBG("sk %p", sk);

	lock_sock(sk);

	switch (optname) {
	case L2CAP_OPTIONS:
		if (sk->sk_state == BT_CONNECTED) {
			err = -EINVAL;
			break;
		}

		opts.imtu     = chan->imtu;
		opts.omtu     = chan->omtu;
		opts.flush_to = chan->flush_to;
		opts.mode     = chan->mode;
		opts.fcs      = chan->fcs;
		opts.max_tx   = chan->max_tx;
		opts.txwin_size = chan->tx_win;

		len = min_t(unsigned int, sizeof(opts), optlen);
		if (copy_from_user((char *) &opts, optval, len)) {
			err = -EFAULT;
			break;
		}

		if (opts.txwin_size > L2CAP_DEFAULT_EXT_WINDOW) {
			err = -EINVAL;
			break;
		}

		if (!l2cap_valid_mtu(chan, opts.imtu)) {
			err = -EINVAL;
			break;
		}

		chan->mode = opts.mode;
		switch (chan->mode) {
		case L2CAP_MODE_BASIC:
			clear_bit(CONF_STATE2_DEVICE, &chan->conf_state);
			break;
		case L2CAP_MODE_ERTM:
		case L2CAP_MODE_STREAMING:
			if (!disable_ertm)
				break;
			/* fall through */
		default:
			err = -EINVAL;
			break;
		}

		chan->imtu = opts.imtu;
		chan->omtu = opts.omtu;
		chan->fcs  = opts.fcs;
		chan->max_tx = opts.max_tx;
		chan->tx_win = opts.txwin_size;
		break;

	case L2CAP_LM:
		if (get_user(opt, (u32 __user *) optval)) {
			err = -EFAULT;
			break;
		}

		if (opt & L2CAP_LM_AUTH)
			chan->sec_level = BT_SECURITY_LOW;
		if (opt & L2CAP_LM_ENCRYPT)
			chan->sec_level = BT_SECURITY_MEDIUM;
		if (opt & L2CAP_LM_SECURE)
			chan->sec_level = BT_SECURITY_HIGH;

		if (opt & L2CAP_LM_MASTER)
			set_bit(FLAG_ROLE_SWITCH, &chan->flags);
		else
			clear_bit(FLAG_ROLE_SWITCH, &chan->flags);

		if (opt & L2CAP_LM_RELIABLE)
			set_bit(FLAG_FORCE_RELIABLE, &chan->flags);
		else
			clear_bit(FLAG_FORCE_RELIABLE, &chan->flags);
		break;

	default:
		err = -ENOPROTOOPT;
		break;
	}

	release_sock(sk);
	return err;
}

static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
{
	struct sock *sk = sock->sk;
	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
	struct bt_security sec;
	struct bt_power pwr;
	struct l2cap_conn *conn;
	int len, err = 0;
	u32 opt;

	BT_DBG("sk %p", sk);

	if (level == SOL_L2CAP)
		return l2cap_sock_setsockopt_old(sock, optname, optval, optlen);

	if (level != SOL_BLUETOOTH)
		return -ENOPROTOOPT;

	lock_sock(sk);

	switch (optname) {
	case BT_SECURITY:
		if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED &&
					chan->chan_type != L2CAP_CHAN_RAW) {
			err = -EINVAL;
			break;
		}

		sec.level = BT_SECURITY_LOW;

		len = min_t(unsigned int, sizeof(sec), optlen);
		if (copy_from_user((char *) &sec, optval, len)) {
			err = -EFAULT;
			break;
		}

		if (sec.level < BT_SECURITY_LOW ||
					sec.level > BT_SECURITY_HIGH) {
			err = -EINVAL;
			break;
		}

		chan->sec_level = sec.level;

		if (!chan->conn)
			break;

		conn = chan->conn;

		/*change security for LE channels */
		if (chan->scid == L2CAP_CID_LE_DATA) {
			if (!conn->hcon->out) {
				err = -EINVAL;
				break;
			}

			if (smp_conn_security(conn, sec.level))
				break;
			sk->sk_state = BT_CONFIG;
			chan->state = BT_CONFIG;

		/* or for ACL link */
		} else if ((sk->sk_state == BT_CONNECT2 &&
			   test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags)) ||
			   sk->sk_state == BT_CONNECTED) {
			if (!l2cap_chan_check_security(chan))
				set_bit(BT_SK_SUSPEND, &bt_sk(sk)->flags);
			else
				sk->sk_state_change(sk);
		} else {
			err = -EINVAL;
		}
		break;

	case BT_DEFER_SETUP:
		if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
			err = -EINVAL;
			break;
		}

		if (get_user(opt, (u32 __user *) optval)) {
			err = -EFAULT;
			break;
		}

		if (opt)
			set_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags);
		else
			clear_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags);
		break;

	case BT_FLUSHABLE:
		if (get_user(opt, (u32 __user *) optval)) {
			err = -EFAULT;
			break;
		}

		if (opt > BT_FLUSHABLE_ON) {
			err = -EINVAL;
			break;
		}

		if (opt == BT_FLUSHABLE_OFF) {
			struct l2cap_conn *conn = chan->conn;
			/* proceed further only when we have l2cap_conn and
			   No Flush support in the LM */
			if (!conn || !lmp_no_flush_capable(conn->hcon->hdev)) {
				err = -EINVAL;
				break;
			}
		}

		if (opt)
			set_bit(FLAG_FLUSHABLE, &chan->flags);
		else
			clear_bit(FLAG_FLUSHABLE, &chan->flags);
		break;

	case BT_POWER:
		if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED &&
					chan->chan_type != L2CAP_CHAN_RAW) {
			err = -EINVAL;
			break;
		}

		pwr.force_active = BT_POWER_FORCE_ACTIVE_ON;

		len = min_t(unsigned int, sizeof(pwr), optlen);
		if (copy_from_user((char *) &pwr, optval, len)) {
			err = -EFAULT;
			break;
		}

		if (pwr.force_active)
			set_bit(FLAG_FORCE_ACTIVE, &chan->flags);
		else
			clear_bit(FLAG_FORCE_ACTIVE, &chan->flags);
		break;

	case BT_CHANNEL_POLICY:
		if (!enable_hs) {
			err = -ENOPROTOOPT;
			break;
		}

		if (get_user(opt, (u32 __user *) optval)) {
			err = -EFAULT;
			break;
		}

		if (opt > BT_CHANNEL_POLICY_AMP_PREFERRED) {
			err = -EINVAL;
			break;
		}

		if (chan->mode != L2CAP_MODE_ERTM &&
				chan->mode != L2CAP_MODE_STREAMING) {
			err = -EOPNOTSUPP;
			break;
		}

		chan->chan_policy = (u8) opt;
		break;

	default:
		err = -ENOPROTOOPT;
		break;
	}

	release_sock(sk);
	return err;
}

static int l2cap_sock_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg, size_t len)
{
	struct sock *sk = sock->sk;
	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
	int err;

	BT_DBG("sock %p, sk %p", sock, sk);

	err = sock_error(sk);
	if (err)
		return err;

	if (msg->msg_flags & MSG_OOB)
		return -EOPNOTSUPP;

	if (sk->sk_state != BT_CONNECTED)
		return -ENOTCONN;

	l2cap_chan_lock(chan);
	err = l2cap_chan_send(chan, msg, len, sk->sk_priority);
	l2cap_chan_unlock(chan);

	return err;
}

static int l2cap_sock_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg, size_t len, int flags)
{
	struct sock *sk = sock->sk;
	struct l2cap_pinfo *pi = l2cap_pi(sk);
	int err;

	lock_sock(sk);

	if (sk->sk_state == BT_CONNECT2 && test_bit(BT_SK_DEFER_SETUP,
						    &bt_sk(sk)->flags)) {
		sk->sk_state = BT_CONFIG;
		pi->chan->state = BT_CONFIG;

		__l2cap_connect_rsp_defer(pi->chan);
		release_sock(sk);
		return 0;
	}

	release_sock(sk);

	if (sock->type == SOCK_STREAM)
		err = bt_sock_stream_recvmsg(iocb, sock, msg, len, flags);
	else
		err = bt_sock_recvmsg(iocb, sock, msg, len, flags);

	if (pi->chan->mode != L2CAP_MODE_ERTM)
		return err;

	/* Attempt to put pending rx data in the socket buffer */

	lock_sock(sk);

	if (!test_bit(CONN_LOCAL_BUSY, &pi->chan->conn_state))
		goto done;

	if (pi->rx_busy_skb) {
		if (!sock_queue_rcv_skb(sk, pi->rx_busy_skb))
			pi->rx_busy_skb = NULL;
		else
			goto done;
	}

	/* Restore data flow when half of the receive buffer is
	 * available.  This avoids resending large numbers of
	 * frames.
	 */
	if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf >> 1)
		l2cap_chan_busy(pi->chan, 0);

done:
	release_sock(sk);
	return err;
}

/* Kill socket (only if zapped and orphan)
 * Must be called on unlocked socket.
 */
static void l2cap_sock_kill(struct sock *sk)
{
	if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
		return;

	BT_DBG("sk %p state %s", sk, state_to_string(sk->sk_state));

	/* Kill poor orphan */

	l2cap_chan_destroy(l2cap_pi(sk)->chan);
	sock_set_flag(sk, SOCK_DEAD);
	sock_put(sk);
}

static int l2cap_sock_shutdown(struct socket *sock, int how)
{
	struct sock *sk = sock->sk;
	struct l2cap_chan *chan;
	struct l2cap_conn *conn;
	int err = 0;

	BT_DBG("sock %p, sk %p", sock, sk);

	if (!sk)
		return 0;

	chan = l2cap_pi(sk)->chan;
	conn = chan->conn;

	if (conn)
		mutex_lock(&conn->chan_lock);

	l2cap_chan_lock(chan);
	lock_sock(sk);

	if (!sk->sk_shutdown) {
		if (chan->mode == L2CAP_MODE_ERTM)
			err = __l2cap_wait_ack(sk);

		sk->sk_shutdown = SHUTDOWN_MASK;

		release_sock(sk);
		l2cap_chan_close(chan, 0);
		lock_sock(sk);

		if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime)
			err = bt_sock_wait_state(sk, BT_CLOSED,
							sk->sk_lingertime);
	}

	if (!err && sk->sk_err)
		err = -sk->sk_err;

	release_sock(sk);
	l2cap_chan_unlock(chan);

	if (conn)
		mutex_unlock(&conn->chan_lock);

	return err;
}

static int l2cap_sock_release(struct socket *sock)
{
	struct sock *sk = sock->sk;
	int err;

	BT_DBG("sock %p, sk %p", sock, sk);

	if (!sk)
		return 0;

	err = l2cap_sock_shutdown(sock, 2);

	sock_orphan(sk);
	l2cap_sock_kill(sk);
	return err;
}

static void l2cap_sock_cleanup_listen(struct sock *parent)
{
	struct sock *sk;

	BT_DBG("parent %p", parent);

	/* Close not yet accepted channels */
	while ((sk = bt_accept_dequeue(parent, NULL))) {
		struct l2cap_chan *chan = l2cap_pi(sk)->chan;

		l2cap_chan_lock(chan);
		__clear_chan_timer(chan);
		l2cap_chan_close(chan, ECONNRESET);
		l2cap_chan_unlock(chan);

		l2cap_sock_kill(sk);
	}
}

static struct l2cap_chan *l2cap_sock_new_connection_cb(struct l2cap_chan *chan)
{
	struct sock *sk, *parent = chan->data;

	/* Check for backlog size */
	if (sk_acceptq_is_full(parent)) {
		BT_DBG("backlog full %d", parent->sk_ack_backlog);
		return NULL;
	}

	sk = l2cap_sock_alloc(sock_net(parent), NULL, BTPROTO_L2CAP,
								GFP_ATOMIC);
	if (!sk)
		return NULL;

	bt_sock_reclassify_lock(sk, BTPROTO_L2CAP);

	l2cap_sock_init(sk, parent);

	return l2cap_pi(sk)->chan;
}

static int l2cap_sock_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
{
	int err;
	struct sock *sk = chan->data;
	struct l2cap_pinfo *pi = l2cap_pi(sk);

	lock_sock(sk);

	if (pi->rx_busy_skb) {
		err = -ENOMEM;
		goto done;
	}

	err = sock_queue_rcv_skb(sk, skb);

	/* For ERTM, handle one skb that doesn't fit into the recv
	 * buffer.  This is important to do because the data frames
	 * have already been acked, so the skb cannot be discarded.
	 *
	 * Notify the l2cap core that the buffer is full, so the
	 * LOCAL_BUSY state is entered and no more frames are
	 * acked and reassembled until there is buffer space
	 * available.
	 */
	if (err < 0 && pi->chan->mode == L2CAP_MODE_ERTM) {
		pi->rx_busy_skb = skb;
		l2cap_chan_busy(pi->chan, 1);
		err = 0;
	}

done:
	release_sock(sk);

	return err;
}

static void l2cap_sock_close_cb(struct l2cap_chan *chan)
{
	struct sock *sk = chan->data;

	l2cap_sock_kill(sk);
}

static void l2cap_sock_teardown_cb(struct l2cap_chan *chan, int err)
{
	struct sock *sk = chan->data;
	struct sock *parent;

	lock_sock(sk);

	parent = bt_sk(sk)->parent;

	sock_set_flag(sk, SOCK_ZAPPED);

	switch (chan->state) {
	case BT_OPEN:
	case BT_BOUND:
	case BT_CLOSED:
		break;
	case BT_LISTEN:
		l2cap_sock_cleanup_listen(sk);
		sk->sk_state = BT_CLOSED;
		chan->state = BT_CLOSED;

		break;
	default:
		sk->sk_state = BT_CLOSED;
		chan->state = BT_CLOSED;

		sk->sk_err = err;

		if (parent) {
			bt_accept_unlink(sk);
			parent->sk_data_ready(parent, 0);
		} else {
			sk->sk_state_change(sk);
		}

		break;
	}

	release_sock(sk);
}

static void l2cap_sock_state_change_cb(struct l2cap_chan *chan, int state)
{
	struct sock *sk = chan->data;

	sk->sk_state = state;
}

static struct sk_buff *l2cap_sock_alloc_skb_cb(struct l2cap_chan *chan,
					       unsigned long len, int nb)
{
	struct sk_buff *skb;
	int err;

	l2cap_chan_unlock(chan);
	skb = bt_skb_send_alloc(chan->sk, len, nb, &err);
	l2cap_chan_lock(chan);

	if (!skb)
		return ERR_PTR(err);

	return skb;
}

static void l2cap_sock_ready_cb(struct l2cap_chan *chan)
{
	struct sock *sk = chan->data;
	struct sock *parent;

	lock_sock(sk);

	parent = bt_sk(sk)->parent;

	BT_DBG("sk %p, parent %p", sk, parent);

	sk->sk_state = BT_CONNECTED;
	sk->sk_state_change(sk);

	if (parent)
		parent->sk_data_ready(parent, 0);

	release_sock(sk);
}

static struct l2cap_ops l2cap_chan_ops = {
	.name		= "L2CAP Socket Interface",
	.new_connection	= l2cap_sock_new_connection_cb,
	.recv		= l2cap_sock_recv_cb,
	.close		= l2cap_sock_close_cb,
	.teardown	= l2cap_sock_teardown_cb,
	.state_change	= l2cap_sock_state_change_cb,
	.ready		= l2cap_sock_ready_cb,
	.alloc_skb	= l2cap_sock_alloc_skb_cb,
};

static void l2cap_sock_destruct(struct sock *sk)
{
	BT_DBG("sk %p", sk);

	l2cap_chan_put(l2cap_pi(sk)->chan);
	if (l2cap_pi(sk)->rx_busy_skb) {
		kfree_skb(l2cap_pi(sk)->rx_busy_skb);
		l2cap_pi(sk)->rx_busy_skb = NULL;
	}

	skb_queue_purge(&sk->sk_receive_queue);
	skb_queue_purge(&sk->sk_write_queue);
}

static void l2cap_sock_init(struct sock *sk, struct sock *parent)
{
	struct l2cap_pinfo *pi = l2cap_pi(sk);
	struct l2cap_chan *chan = pi->chan;

	BT_DBG("sk %p", sk);

	if (parent) {
		struct l2cap_chan *pchan = l2cap_pi(parent)->chan;

		sk->sk_type = parent->sk_type;
		bt_sk(sk)->flags = bt_sk(parent)->flags;

		chan->chan_type = pchan->chan_type;
		chan->imtu = pchan->imtu;
		chan->omtu = pchan->omtu;
		chan->conf_state = pchan->conf_state;
		chan->mode = pchan->mode;
		chan->fcs  = pchan->fcs;
		chan->max_tx = pchan->max_tx;
		chan->tx_win = pchan->tx_win;
		chan->tx_win_max = pchan->tx_win_max;
		chan->sec_level = pchan->sec_level;
		chan->flags = pchan->flags;

		security_sk_clone(parent, sk);
	} else {

		switch (sk->sk_type) {
		case SOCK_RAW:
			chan->chan_type = L2CAP_CHAN_RAW;
			break;
		case SOCK_DGRAM:
			chan->chan_type = L2CAP_CHAN_CONN_LESS;
			break;
		case SOCK_SEQPACKET:
		case SOCK_STREAM:
			chan->chan_type = L2CAP_CHAN_CONN_ORIENTED;
			break;
		}

		chan->imtu = L2CAP_DEFAULT_MTU;
		chan->omtu = 0;
		if (!disable_ertm && sk->sk_type == SOCK_STREAM) {
			chan->mode = L2CAP_MODE_ERTM;
			set_bit(CONF_STATE2_DEVICE, &chan->conf_state);
		} else {
			chan->mode = L2CAP_MODE_BASIC;
		}

		l2cap_chan_set_defaults(chan);
	}

	/* Default config options */
	chan->flush_to = L2CAP_DEFAULT_FLUSH_TO;

	chan->data = sk;
	chan->ops = &l2cap_chan_ops;
}

static struct proto l2cap_proto = {
	.name		= "L2CAP",
	.owner		= THIS_MODULE,
	.obj_size	= sizeof(struct l2cap_pinfo)
};

static struct sock *l2cap_sock_alloc(struct net *net, struct socket *sock, int proto, gfp_t prio)
{
	struct sock *sk;
	struct l2cap_chan *chan;

	sk = sk_alloc(net, PF_BLUETOOTH, prio, &l2cap_proto);
	if (!sk)
		return NULL;

	sock_init_data(sock, sk);
	INIT_LIST_HEAD(&bt_sk(sk)->accept_q);

	sk->sk_destruct = l2cap_sock_destruct;
	sk->sk_sndtimeo = L2CAP_CONN_TIMEOUT;

	sock_reset_flag(sk, SOCK_ZAPPED);

	sk->sk_protocol = proto;
	sk->sk_state = BT_OPEN;

	chan = l2cap_chan_create();
	if (!chan) {
		l2cap_sock_kill(sk);
		return NULL;
	}

	l2cap_chan_hold(chan);

	chan->sk = sk;

	l2cap_pi(sk)->chan = chan;

	return sk;
}

static int l2cap_sock_create(struct net *net, struct socket *sock, int protocol,
			     int kern)
{
	struct sock *sk;

	BT_DBG("sock %p", sock);

	sock->state = SS_UNCONNECTED;

	if (sock->type != SOCK_SEQPACKET && sock->type != SOCK_STREAM &&
			sock->type != SOCK_DGRAM && sock->type != SOCK_RAW)
		return -ESOCKTNOSUPPORT;

	if (sock->type == SOCK_RAW && !kern && !capable(CAP_NET_RAW))
		return -EPERM;

	sock->ops = &l2cap_sock_ops;

	sk = l2cap_sock_alloc(net, sock, protocol, GFP_ATOMIC);
	if (!sk)
		return -ENOMEM;

	l2cap_sock_init(sk, NULL);
	return 0;
}

static const struct proto_ops l2cap_sock_ops = {
	.family		= PF_BLUETOOTH,
	.owner		= THIS_MODULE,
	.release	= l2cap_sock_release,
	.bind		= l2cap_sock_bind,
	.connect	= l2cap_sock_connect,
	.listen		= l2cap_sock_listen,
	.accept		= l2cap_sock_accept,
	.getname	= l2cap_sock_getname,
	.sendmsg	= l2cap_sock_sendmsg,
	.recvmsg	= l2cap_sock_recvmsg,
	.poll		= bt_sock_poll,
	.ioctl		= bt_sock_ioctl,
	.mmap		= sock_no_mmap,
	.socketpair	= sock_no_socketpair,
	.shutdown	= l2cap_sock_shutdown,
	.setsockopt	= l2cap_sock_setsockopt,
	.getsockopt	= l2cap_sock_getsockopt
};

static const struct net_proto_family l2cap_sock_family_ops = {
	.family	= PF_BLUETOOTH,
	.owner	= THIS_MODULE,
	.create	= l2cap_sock_create,
};

int __init l2cap_init_sockets(void)
{
	int err;

	err = proto_register(&l2cap_proto, 0);
	if (err < 0)
		return err;

	err = bt_sock_register(BTPROTO_L2CAP, &l2cap_sock_family_ops);
	if (err < 0)
		goto error;

	BT_INFO("L2CAP socket layer initialized");

	return 0;

error:
	BT_ERR("L2CAP socket registration failed");
	proto_unregister(&l2cap_proto);
	return err;
}

void l2cap_cleanup_sockets(void)
{
	if (bt_sock_unregister(BTPROTO_L2CAP) < 0)
		BT_ERR("L2CAP socket unregistration failed");

	proto_unregister(&l2cap_proto);
}