summaryrefslogtreecommitdiffstats
path: root/net/can/j1939/socket.c
blob: 6dff4510687a49791a4e6c01f3f5fe12669d8153 (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
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
// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2010-2011 EIA Electronics,
//                         Pieter Beyens <pieter.beyens@eia.be>
// Copyright (c) 2010-2011 EIA Electronics,
//                         Kurt Van Dijck <kurt.van.dijck@eia.be>
// Copyright (c) 2018 Protonic,
//                         Robin van der Gracht <robin@protonic.nl>
// Copyright (c) 2017-2019 Pengutronix,
//                         Marc Kleine-Budde <kernel@pengutronix.de>
// Copyright (c) 2017-2019 Pengutronix,
//                         Oleksij Rempel <kernel@pengutronix.de>

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/can/can-ml.h>
#include <linux/can/core.h>
#include <linux/can/skb.h>
#include <linux/errqueue.h>
#include <linux/if_arp.h>

#include "j1939-priv.h"

#define J1939_MIN_NAMELEN CAN_REQUIRED_SIZE(struct sockaddr_can, can_addr.j1939)

/* conversion function between struct sock::sk_priority from linux and
 * j1939 priority field
 */
static inline priority_t j1939_prio(u32 sk_priority)
{
	sk_priority = min(sk_priority, 7U);

	return 7 - sk_priority;
}

static inline u32 j1939_to_sk_priority(priority_t prio)
{
	return 7 - prio;
}

/* function to see if pgn is to be evaluated */
static inline bool j1939_pgn_is_valid(pgn_t pgn)
{
	return pgn <= J1939_PGN_MAX;
}

/* test function to avoid non-zero DA placeholder for pdu1 pgn's */
static inline bool j1939_pgn_is_clean_pdu(pgn_t pgn)
{
	if (j1939_pgn_is_pdu1(pgn))
		return !(pgn & 0xff);
	else
		return true;
}

static inline void j1939_sock_pending_add(struct sock *sk)
{
	struct j1939_sock *jsk = j1939_sk(sk);

	atomic_inc(&jsk->skb_pending);
}

static int j1939_sock_pending_get(struct sock *sk)
{
	struct j1939_sock *jsk = j1939_sk(sk);

	return atomic_read(&jsk->skb_pending);
}

void j1939_sock_pending_del(struct sock *sk)
{
	struct j1939_sock *jsk = j1939_sk(sk);

	/* atomic_dec_return returns the new value */
	if (!atomic_dec_return(&jsk->skb_pending))
		wake_up(&jsk->waitq);	/* no pending SKB's */
}

static void j1939_jsk_add(struct j1939_priv *priv, struct j1939_sock *jsk)
{
	jsk->state |= J1939_SOCK_BOUND;
	j1939_priv_get(priv);

	spin_lock_bh(&priv->j1939_socks_lock);
	list_add_tail(&jsk->list, &priv->j1939_socks);
	spin_unlock_bh(&priv->j1939_socks_lock);
}

static void j1939_jsk_del(struct j1939_priv *priv, struct j1939_sock *jsk)
{
	spin_lock_bh(&priv->j1939_socks_lock);
	list_del_init(&jsk->list);
	spin_unlock_bh(&priv->j1939_socks_lock);

	j1939_priv_put(priv);
	jsk->state &= ~J1939_SOCK_BOUND;
}

static bool j1939_sk_queue_session(struct j1939_session *session)
{
	struct j1939_sock *jsk = j1939_sk(session->sk);
	bool empty;

	spin_lock_bh(&jsk->sk_session_queue_lock);
	empty = list_empty(&jsk->sk_session_queue);
	j1939_session_get(session);
	list_add_tail(&session->sk_session_queue_entry, &jsk->sk_session_queue);
	spin_unlock_bh(&jsk->sk_session_queue_lock);
	j1939_sock_pending_add(&jsk->sk);

	return empty;
}

static struct
j1939_session *j1939_sk_get_incomplete_session(struct j1939_sock *jsk)
{
	struct j1939_session *session = NULL;

	spin_lock_bh(&jsk->sk_session_queue_lock);
	if (!list_empty(&jsk->sk_session_queue)) {
		session = list_last_entry(&jsk->sk_session_queue,
					  struct j1939_session,
					  sk_session_queue_entry);
		if (session->total_queued_size == session->total_message_size)
			session = NULL;
		else
			j1939_session_get(session);
	}
	spin_unlock_bh(&jsk->sk_session_queue_lock);

	return session;
}

static void j1939_sk_queue_drop_all(struct j1939_priv *priv,
				    struct j1939_sock *jsk, int err)
{
	struct j1939_session *session, *tmp;

	netdev_dbg(priv->ndev, "%s: err: %i\n", __func__, err);
	spin_lock_bh(&jsk->sk_session_queue_lock);
	list_for_each_entry_safe(session, tmp, &jsk->sk_session_queue,
				 sk_session_queue_entry) {
		list_del_init(&session->sk_session_queue_entry);
		session->err = err;
		j1939_session_put(session);
	}
	spin_unlock_bh(&jsk->sk_session_queue_lock);
}

static void j1939_sk_queue_activate_next_locked(struct j1939_session *session)
{
	struct j1939_sock *jsk;
	struct j1939_session *first;
	int err;

	/* RX-Session don't have a socket (yet) */
	if (!session->sk)
		return;

	jsk = j1939_sk(session->sk);
	lockdep_assert_held(&jsk->sk_session_queue_lock);

	err = session->err;

	first = list_first_entry_or_null(&jsk->sk_session_queue,
					 struct j1939_session,
					 sk_session_queue_entry);

	/* Some else has already activated the next session */
	if (first != session)
		return;

activate_next:
	list_del_init(&first->sk_session_queue_entry);
	j1939_session_put(first);
	first = list_first_entry_or_null(&jsk->sk_session_queue,
					 struct j1939_session,
					 sk_session_queue_entry);
	if (!first)
		return;

	if (WARN_ON_ONCE(j1939_session_activate(first))) {
		first->err = -EBUSY;
		goto activate_next;
	} else {
		/* Give receiver some time (arbitrary chosen) to recover */
		int time_ms = 0;

		if (err)
			time_ms = 10 + prandom_u32_max(16);

		j1939_tp_schedule_txtimer(first, time_ms);
	}
}

void j1939_sk_queue_activate_next(struct j1939_session *session)
{
	struct j1939_sock *jsk;

	if (!session->sk)
		return;

	jsk = j1939_sk(session->sk);

	spin_lock_bh(&jsk->sk_session_queue_lock);
	j1939_sk_queue_activate_next_locked(session);
	spin_unlock_bh(&jsk->sk_session_queue_lock);
}

static bool j1939_sk_match_dst(struct j1939_sock *jsk,
			       const struct j1939_sk_buff_cb *skcb)
{
	if ((jsk->state & J1939_SOCK_PROMISC))
		return true;

	/* Destination address filter */
	if (jsk->addr.src_name && skcb->addr.dst_name) {
		if (jsk->addr.src_name != skcb->addr.dst_name)
			return false;
	} else {
		/* receive (all sockets) if
		 * - all packages that match our bind() address
		 * - all broadcast on a socket if SO_BROADCAST
		 *   is set
		 */
		if (j1939_address_is_unicast(skcb->addr.da)) {
			if (jsk->addr.sa != skcb->addr.da)
				return false;
		} else if (!sock_flag(&jsk->sk, SOCK_BROADCAST)) {
			/* receiving broadcast without SO_BROADCAST
			 * flag is not allowed
			 */
			return false;
		}
	}

	/* Source address filter */
	if (jsk->state & J1939_SOCK_CONNECTED) {
		/* receive (all sockets) if
		 * - all packages that match our connect() name or address
		 */
		if (jsk->addr.dst_name && skcb->addr.src_name) {
			if (jsk->addr.dst_name != skcb->addr.src_name)
				return false;
		} else {
			if (jsk->addr.da != skcb->addr.sa)
				return false;
		}
	}

	/* PGN filter */
	if (j1939_pgn_is_valid(jsk->pgn_rx_filter) &&
	    jsk->pgn_rx_filter != skcb->addr.pgn)
		return false;

	return true;
}

/* matches skb control buffer (addr) with a j1939 filter */
static bool j1939_sk_match_filter(struct j1939_sock *jsk,
				  const struct j1939_sk_buff_cb *skcb)
{
	const struct j1939_filter *f = jsk->filters;
	int nfilter = jsk->nfilters;

	if (!nfilter)
		/* receive all when no filters are assigned */
		return true;

	for (; nfilter; ++f, --nfilter) {
		if ((skcb->addr.pgn & f->pgn_mask) != f->pgn)
			continue;
		if ((skcb->addr.sa & f->addr_mask) != f->addr)
			continue;
		if ((skcb->addr.src_name & f->name_mask) != f->name)
			continue;
		return true;
	}
	return false;
}

static bool j1939_sk_recv_match_one(struct j1939_sock *jsk,
				    const struct j1939_sk_buff_cb *skcb)
{
	if (!(jsk->state & J1939_SOCK_BOUND))
		return false;

	if (!j1939_sk_match_dst(jsk, skcb))
		return false;

	if (!j1939_sk_match_filter(jsk, skcb))
		return false;

	return true;
}

static void j1939_sk_recv_one(struct j1939_sock *jsk, struct sk_buff *oskb)
{
	const struct j1939_sk_buff_cb *oskcb = j1939_skb_to_cb(oskb);
	struct j1939_sk_buff_cb *skcb;
	struct sk_buff *skb;

	if (oskb->sk == &jsk->sk)
		return;

	if (!j1939_sk_recv_match_one(jsk, oskcb))
		return;

	skb = skb_clone(oskb, GFP_ATOMIC);
	if (!skb) {
		pr_warn("skb clone failed\n");
		return;
	}
	can_skb_set_owner(skb, oskb->sk);

	skcb = j1939_skb_to_cb(skb);
	skcb->msg_flags &= ~(MSG_DONTROUTE);
	if (skb->sk)
		skcb->msg_flags |= MSG_DONTROUTE;

	if (sock_queue_rcv_skb(&jsk->sk, skb) < 0)
		kfree_skb(skb);
}

bool j1939_sk_recv_match(struct j1939_priv *priv, struct j1939_sk_buff_cb *skcb)
{
	struct j1939_sock *jsk;
	bool match = false;

	spin_lock_bh(&priv->j1939_socks_lock);
	list_for_each_entry(jsk, &priv->j1939_socks, list) {
		match = j1939_sk_recv_match_one(jsk, skcb);
		if (match)
			break;
	}
	spin_unlock_bh(&priv->j1939_socks_lock);

	return match;
}

void j1939_sk_recv(struct j1939_priv *priv, struct sk_buff *skb)
{
	struct j1939_sock *jsk;

	spin_lock_bh(&priv->j1939_socks_lock);
	list_for_each_entry(jsk, &priv->j1939_socks, list) {
		j1939_sk_recv_one(jsk, skb);
	}
	spin_unlock_bh(&priv->j1939_socks_lock);
}

static void j1939_sk_sock_destruct(struct sock *sk)
{
	struct j1939_sock *jsk = j1939_sk(sk);

	/* This function will be called by the generic networking code, when
	 * the socket is ultimately closed (sk->sk_destruct).
	 *
	 * The race between
	 * - processing a received CAN frame
	 *   (can_receive -> j1939_can_recv)
	 *   and accessing j1939_priv
	 * ... and ...
	 * - closing a socket
	 *   (j1939_can_rx_unregister -> can_rx_unregister)
	 *   and calling the final j1939_priv_put()
	 *
	 * is avoided by calling the final j1939_priv_put() from this
	 * RCU deferred cleanup call.
	 */
	if (jsk->priv) {
		j1939_priv_put(jsk->priv);
		jsk->priv = NULL;
	}

	/* call generic CAN sock destruct */
	can_sock_destruct(sk);
}

static int j1939_sk_init(struct sock *sk)
{
	struct j1939_sock *jsk = j1939_sk(sk);

	/* Ensure that "sk" is first member in "struct j1939_sock", so that we
	 * can skip it during memset().
	 */
	BUILD_BUG_ON(offsetof(struct j1939_sock, sk) != 0);
	memset((void *)jsk + sizeof(jsk->sk), 0x0,
	       sizeof(*jsk) - sizeof(jsk->sk));

	INIT_LIST_HEAD(&jsk->list);
	init_waitqueue_head(&jsk->waitq);
	jsk->sk.sk_priority = j1939_to_sk_priority(6);
	jsk->sk.sk_reuse = 1; /* per default */
	jsk->addr.sa = J1939_NO_ADDR;
	jsk->addr.da = J1939_NO_ADDR;
	jsk->addr.pgn = J1939_NO_PGN;
	jsk->pgn_rx_filter = J1939_NO_PGN;
	atomic_set(&jsk->skb_pending, 0);
	spin_lock_init(&jsk->sk_session_queue_lock);
	INIT_LIST_HEAD(&jsk->sk_session_queue);

	/* j1939_sk_sock_destruct() depends on SOCK_RCU_FREE flag */
	sock_set_flag(sk, SOCK_RCU_FREE);
	sk->sk_destruct = j1939_sk_sock_destruct;
	sk->sk_protocol = CAN_J1939;

	return 0;
}

static int j1939_sk_sanity_check(struct sockaddr_can *addr, int len)
{
	if (!addr)
		return -EDESTADDRREQ;
	if (len < J1939_MIN_NAMELEN)
		return -EINVAL;
	if (addr->can_family != AF_CAN)
		return -EINVAL;
	if (!addr->can_ifindex)
		return -ENODEV;
	if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn) &&
	    !j1939_pgn_is_clean_pdu(addr->can_addr.j1939.pgn))
		return -EINVAL;

	return 0;
}

static int j1939_sk_bind(struct socket *sock, struct sockaddr *uaddr, int len)
{
	struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
	struct j1939_sock *jsk = j1939_sk(sock->sk);
	struct j1939_priv *priv;
	struct sock *sk;
	struct net *net;
	int ret = 0;

	ret = j1939_sk_sanity_check(addr, len);
	if (ret)
		return ret;

	lock_sock(sock->sk);

	priv = jsk->priv;
	sk = sock->sk;
	net = sock_net(sk);

	/* Already bound to an interface? */
	if (jsk->state & J1939_SOCK_BOUND) {
		/* A re-bind() to a different interface is not
		 * supported.
		 */
		if (jsk->ifindex != addr->can_ifindex) {
			ret = -EINVAL;
			goto out_release_sock;
		}

		/* drop old references */
		j1939_jsk_del(priv, jsk);
		j1939_local_ecu_put(priv, jsk->addr.src_name, jsk->addr.sa);
	} else {
		struct can_ml_priv *can_ml;
		struct net_device *ndev;

		ndev = dev_get_by_index(net, addr->can_ifindex);
		if (!ndev) {
			ret = -ENODEV;
			goto out_release_sock;
		}

		can_ml = can_get_ml_priv(ndev);
		if (!can_ml) {
			dev_put(ndev);
			ret = -ENODEV;
			goto out_release_sock;
		}

		if (!(ndev->flags & IFF_UP)) {
			dev_put(ndev);
			ret = -ENETDOWN;
			goto out_release_sock;
		}

		priv = j1939_netdev_start(ndev);
		dev_put(ndev);
		if (IS_ERR(priv)) {
			ret = PTR_ERR(priv);
			goto out_release_sock;
		}

		jsk->ifindex = addr->can_ifindex;

		/* the corresponding j1939_priv_put() is called via
		 * sk->sk_destruct, which points to j1939_sk_sock_destruct()
		 */
		j1939_priv_get(priv);
		jsk->priv = priv;
	}

	/* set default transmit pgn */
	if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn))
		jsk->pgn_rx_filter = addr->can_addr.j1939.pgn;
	jsk->addr.src_name = addr->can_addr.j1939.name;
	jsk->addr.sa = addr->can_addr.j1939.addr;

	/* get new references */
	ret = j1939_local_ecu_get(priv, jsk->addr.src_name, jsk->addr.sa);
	if (ret) {
		j1939_netdev_stop(priv);
		goto out_release_sock;
	}

	j1939_jsk_add(priv, jsk);

 out_release_sock: /* fall through */
	release_sock(sock->sk);

	return ret;
}

static int j1939_sk_connect(struct socket *sock, struct sockaddr *uaddr,
			    int len, int flags)
{
	struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
	struct j1939_sock *jsk = j1939_sk(sock->sk);
	int ret = 0;

	ret = j1939_sk_sanity_check(addr, len);
	if (ret)
		return ret;

	lock_sock(sock->sk);

	/* bind() before connect() is mandatory */
	if (!(jsk->state & J1939_SOCK_BOUND)) {
		ret = -EINVAL;
		goto out_release_sock;
	}

	/* A connect() to a different interface is not supported. */
	if (jsk->ifindex != addr->can_ifindex) {
		ret = -EINVAL;
		goto out_release_sock;
	}

	if (!addr->can_addr.j1939.name &&
	    addr->can_addr.j1939.addr == J1939_NO_ADDR &&
	    !sock_flag(&jsk->sk, SOCK_BROADCAST)) {
		/* broadcast, but SO_BROADCAST not set */
		ret = -EACCES;
		goto out_release_sock;
	}

	jsk->addr.dst_name = addr->can_addr.j1939.name;
	jsk->addr.da = addr->can_addr.j1939.addr;

	if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn))
		jsk->addr.pgn = addr->can_addr.j1939.pgn;

	jsk->state |= J1939_SOCK_CONNECTED;

 out_release_sock: /* fall through */
	release_sock(sock->sk);

	return ret;
}

static void j1939_sk_sock2sockaddr_can(struct sockaddr_can *addr,
				       const struct j1939_sock *jsk, int peer)
{
	/* There are two holes (2 bytes and 3 bytes) to clear to avoid
	 * leaking kernel information to user space.
	 */
	memset(addr, 0, J1939_MIN_NAMELEN);

	addr->can_family = AF_CAN;
	addr->can_ifindex = jsk->ifindex;
	addr->can_addr.j1939.pgn = jsk->addr.pgn;
	if (peer) {
		addr->can_addr.j1939.name = jsk->addr.dst_name;
		addr->can_addr.j1939.addr = jsk->addr.da;
	} else {
		addr->can_addr.j1939.name = jsk->addr.src_name;
		addr->can_addr.j1939.addr = jsk->addr.sa;
	}
}

static int j1939_sk_getname(struct socket *sock, struct sockaddr *uaddr,
			    int peer)
{
	struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
	struct sock *sk = sock->sk;
	struct j1939_sock *jsk = j1939_sk(sk);
	int ret = 0;

	lock_sock(sk);

	if (peer && !(jsk->state & J1939_SOCK_CONNECTED)) {
		ret = -EADDRNOTAVAIL;
		goto failure;
	}

	j1939_sk_sock2sockaddr_can(addr, jsk, peer);
	ret = J1939_MIN_NAMELEN;

 failure:
	release_sock(sk);

	return ret;
}

static int j1939_sk_release(struct socket *sock)
{
	struct sock *sk = sock->sk;
	struct j1939_sock *jsk;

	if (!sk)
		return 0;

	lock_sock(sk);
	jsk = j1939_sk(sk);

	if (jsk->state & J1939_SOCK_BOUND) {
		struct j1939_priv *priv = jsk->priv;

		if (wait_event_interruptible(jsk->waitq,
					     !j1939_sock_pending_get(&jsk->sk))) {
			j1939_cancel_active_session(priv, sk);
			j1939_sk_queue_drop_all(priv, jsk, ESHUTDOWN);
		}

		j1939_jsk_del(priv, jsk);

		j1939_local_ecu_put(priv, jsk->addr.src_name,
				    jsk->addr.sa);

		j1939_netdev_stop(priv);
	}

	kfree(jsk->filters);
	sock_orphan(sk);
	sock->sk = NULL;

	release_sock(sk);
	sock_put(sk);

	return 0;
}

static int j1939_sk_setsockopt_flag(struct j1939_sock *jsk, sockptr_t optval,
				    unsigned int optlen, int flag)
{
	int tmp;

	if (optlen != sizeof(tmp))
		return -EINVAL;
	if (copy_from_sockptr(&tmp, optval, optlen))
		return -EFAULT;
	lock_sock(&jsk->sk);
	if (tmp)
		jsk->state |= flag;
	else
		jsk->state &= ~flag;
	release_sock(&jsk->sk);
	return tmp;
}

static int j1939_sk_setsockopt(struct socket *sock, int level, int optname,
			       sockptr_t optval, unsigned int optlen)
{
	struct sock *sk = sock->sk;
	struct j1939_sock *jsk = j1939_sk(sk);
	int tmp, count = 0, ret = 0;
	struct j1939_filter *filters = NULL, *ofilters;

	if (level != SOL_CAN_J1939)
		return -EINVAL;

	switch (optname) {
	case SO_J1939_FILTER:
		if (!sockptr_is_null(optval) && optlen != 0) {
			struct j1939_filter *f;
			int c;

			if (optlen % sizeof(*filters) != 0)
				return -EINVAL;

			if (optlen > J1939_FILTER_MAX *
			    sizeof(struct j1939_filter))
				return -EINVAL;

			count = optlen / sizeof(*filters);
			filters = memdup_sockptr(optval, optlen);
			if (IS_ERR(filters))
				return PTR_ERR(filters);

			for (f = filters, c = count; c; f++, c--) {
				f->name &= f->name_mask;
				f->pgn &= f->pgn_mask;
				f->addr &= f->addr_mask;
			}
		}

		lock_sock(&jsk->sk);
		ofilters = jsk->filters;
		jsk->filters = filters;
		jsk->nfilters = count;
		release_sock(&jsk->sk);
		kfree(ofilters);
		return 0;
	case SO_J1939_PROMISC:
		return j1939_sk_setsockopt_flag(jsk, optval, optlen,
						J1939_SOCK_PROMISC);
	case SO_J1939_ERRQUEUE:
		ret = j1939_sk_setsockopt_flag(jsk, optval, optlen,
					       J1939_SOCK_ERRQUEUE);
		if (ret < 0)
			return ret;

		if (!(jsk->state & J1939_SOCK_ERRQUEUE))
			skb_queue_purge(&sk->sk_error_queue);
		return ret;
	case SO_J1939_SEND_PRIO:
		if (optlen != sizeof(tmp))
			return -EINVAL;
		if (copy_from_sockptr(&tmp, optval, optlen))
			return -EFAULT;
		if (tmp < 0 || tmp > 7)
			return -EDOM;
		if (tmp < 2 && !capable(CAP_NET_ADMIN))
			return -EPERM;
		lock_sock(&jsk->sk);
		jsk->sk.sk_priority = j1939_to_sk_priority(tmp);
		release_sock(&jsk->sk);
		return 0;
	default:
		return -ENOPROTOOPT;
	}
}

static int j1939_sk_getsockopt(struct socket *sock, int level, int optname,
			       char __user *optval, int __user *optlen)
{
	struct sock *sk = sock->sk;
	struct j1939_sock *jsk = j1939_sk(sk);
	int ret, ulen;
	/* set defaults for using 'int' properties */
	int tmp = 0;
	int len = sizeof(tmp);
	void *val = &tmp;

	if (level != SOL_CAN_J1939)
		return -EINVAL;
	if (get_user(ulen, optlen))
		return -EFAULT;
	if (ulen < 0)
		return -EINVAL;

	lock_sock(&jsk->sk);
	switch (optname) {
	case SO_J1939_PROMISC:
		tmp = (jsk->state & J1939_SOCK_PROMISC) ? 1 : 0;
		break;
	case SO_J1939_ERRQUEUE:
		tmp = (jsk->state & J1939_SOCK_ERRQUEUE) ? 1 : 0;
		break;
	case SO_J1939_SEND_PRIO:
		tmp = j1939_prio(jsk->sk.sk_priority);
		break;
	default:
		ret = -ENOPROTOOPT;
		goto no_copy;
	}

	/* copy to user, based on 'len' & 'val'
	 * but most sockopt's are 'int' properties, and have 'len' & 'val'
	 * left unchanged, but instead modified 'tmp'
	 */
	if (len > ulen)
		ret = -EFAULT;
	else if (put_user(len, optlen))
		ret = -EFAULT;
	else if (copy_to_user(optval, val, len))
		ret = -EFAULT;
	else
		ret = 0;
 no_copy:
	release_sock(&jsk->sk);
	return ret;
}

static int j1939_sk_recvmsg(struct socket *sock, struct msghdr *msg,
			    size_t size, int flags)
{
	struct sock *sk = sock->sk;
	struct sk_buff *skb;
	struct j1939_sk_buff_cb *skcb;
	int ret = 0;

	if (flags & ~(MSG_DONTWAIT | MSG_ERRQUEUE))
		return -EINVAL;

	if (flags & MSG_ERRQUEUE)
		return sock_recv_errqueue(sock->sk, msg, size, SOL_CAN_J1939,
					  SCM_J1939_ERRQUEUE);

	skb = skb_recv_datagram(sk, flags, 0, &ret);
	if (!skb)
		return ret;

	if (size < skb->len)
		msg->msg_flags |= MSG_TRUNC;
	else
		size = skb->len;

	ret = memcpy_to_msg(msg, skb->data, size);
	if (ret < 0) {
		skb_free_datagram(sk, skb);
		return ret;
	}

	skcb = j1939_skb_to_cb(skb);
	if (j1939_address_is_valid(skcb->addr.da))
		put_cmsg(msg, SOL_CAN_J1939, SCM_J1939_DEST_ADDR,
			 sizeof(skcb->addr.da), &skcb->addr.da);

	if (skcb->addr.dst_name)
		put_cmsg(msg, SOL_CAN_J1939, SCM_J1939_DEST_NAME,
			 sizeof(skcb->addr.dst_name), &skcb->addr.dst_name);

	put_cmsg(msg, SOL_CAN_J1939, SCM_J1939_PRIO,
		 sizeof(skcb->priority), &skcb->priority);

	if (msg->msg_name) {
		struct sockaddr_can *paddr = msg->msg_name;

		msg->msg_namelen = J1939_MIN_NAMELEN;
		memset(msg->msg_name, 0, msg->msg_namelen);
		paddr->can_family = AF_CAN;
		paddr->can_ifindex = skb->skb_iif;
		paddr->can_addr.j1939.name = skcb->addr.src_name;
		paddr->can_addr.j1939.addr = skcb->addr.sa;
		paddr->can_addr.j1939.pgn = skcb->addr.pgn;
	}

	sock_recv_ts_and_drops(msg, sk, skb);
	msg->msg_flags |= skcb->msg_flags;
	skb_free_datagram(sk, skb);

	return size;
}

static struct sk_buff *j1939_sk_alloc_skb(struct net_device *ndev,
					  struct sock *sk,
					  struct msghdr *msg, size_t size,
					  int *errcode)
{
	struct j1939_sock *jsk = j1939_sk(sk);
	struct j1939_sk_buff_cb *skcb;
	struct sk_buff *skb;
	int ret;

	skb = sock_alloc_send_skb(sk,
				  size +
				  sizeof(struct can_frame) -
				  sizeof(((struct can_frame *)NULL)->data) +
				  sizeof(struct can_skb_priv),
				  msg->msg_flags & MSG_DONTWAIT, &ret);
	if (!skb)
		goto failure;

	can_skb_reserve(skb);
	can_skb_prv(skb)->ifindex = ndev->ifindex;
	can_skb_prv(skb)->skbcnt = 0;
	skb_reserve(skb, offsetof(struct can_frame, data));

	ret = memcpy_from_msg(skb_put(skb, size), msg, size);
	if (ret < 0)
		goto free_skb;

	skb->dev = ndev;

	skcb = j1939_skb_to_cb(skb);
	memset(skcb, 0, sizeof(*skcb));
	skcb->addr = jsk->addr;
	skcb->priority = j1939_prio(sk->sk_priority);

	if (msg->msg_name) {
		struct sockaddr_can *addr = msg->msg_name;

		if (addr->can_addr.j1939.name ||
		    addr->can_addr.j1939.addr != J1939_NO_ADDR) {
			skcb->addr.dst_name = addr->can_addr.j1939.name;
			skcb->addr.da = addr->can_addr.j1939.addr;
		}
		if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn))
			skcb->addr.pgn = addr->can_addr.j1939.pgn;
	}

	*errcode = ret;
	return skb;

free_skb:
	kfree_skb(skb);
failure:
	*errcode = ret;
	return NULL;
}

static size_t j1939_sk_opt_stats_get_size(enum j1939_sk_errqueue_type type)
{
	switch (type) {
	case J1939_ERRQUEUE_RX_RTS:
		return
			nla_total_size(sizeof(u32)) + /* J1939_NLA_TOTAL_SIZE */
			nla_total_size(sizeof(u32)) + /* J1939_NLA_PGN */
			nla_total_size(sizeof(u64)) + /* J1939_NLA_SRC_NAME */
			nla_total_size(sizeof(u64)) + /* J1939_NLA_DEST_NAME */
			nla_total_size(sizeof(u8)) +  /* J1939_NLA_SRC_ADDR */
			nla_total_size(sizeof(u8)) +  /* J1939_NLA_DEST_ADDR */
			0;
	default:
		return
			nla_total_size(sizeof(u32)) + /* J1939_NLA_BYTES_ACKED */
			0;
	}
}

static struct sk_buff *
j1939_sk_get_timestamping_opt_stats(struct j1939_session *session,
				    enum j1939_sk_errqueue_type type)
{
	struct sk_buff *stats;
	u32 size;

	stats = alloc_skb(j1939_sk_opt_stats_get_size(type), GFP_ATOMIC);
	if (!stats)
		return NULL;

	if (session->skcb.addr.type == J1939_SIMPLE)
		size = session->total_message_size;
	else
		size = min(session->pkt.tx_acked * 7,
			   session->total_message_size);

	switch (type) {
	case J1939_ERRQUEUE_RX_RTS:
		nla_put_u32(stats, J1939_NLA_TOTAL_SIZE,
			    session->total_message_size);
		nla_put_u32(stats, J1939_NLA_PGN,
			    session->skcb.addr.pgn);
		nla_put_u64_64bit(stats, J1939_NLA_SRC_NAME,
				  session->skcb.addr.src_name, J1939_NLA_PAD);
		nla_put_u64_64bit(stats, J1939_NLA_DEST_NAME,
				  session->skcb.addr.dst_name, J1939_NLA_PAD);
		nla_put_u8(stats, J1939_NLA_SRC_ADDR,
			   session->skcb.addr.sa);
		nla_put_u8(stats, J1939_NLA_DEST_ADDR,
			   session->skcb.addr.da);
		break;
	default:
		nla_put_u32(stats, J1939_NLA_BYTES_ACKED, size);
	}

	return stats;
}

static void __j1939_sk_errqueue(struct j1939_session *session, struct sock *sk,
				enum j1939_sk_errqueue_type type)
{
	struct j1939_priv *priv = session->priv;
	struct j1939_sock *jsk;
	struct sock_exterr_skb *serr;
	struct sk_buff *skb;
	char *state = "UNK";
	int err;

	jsk = j1939_sk(sk);

	if (!(jsk->state & J1939_SOCK_ERRQUEUE))
		return;

	switch (type) {
	case J1939_ERRQUEUE_TX_ACK:
		if (!(sk->sk_tsflags & SOF_TIMESTAMPING_TX_ACK))
			return;
		break;
	case J1939_ERRQUEUE_TX_SCHED:
		if (!(sk->sk_tsflags & SOF_TIMESTAMPING_TX_SCHED))
			return;
		break;
	case J1939_ERRQUEUE_TX_ABORT:
		break;
	case J1939_ERRQUEUE_RX_RTS:
		fallthrough;
	case J1939_ERRQUEUE_RX_DPO:
		fallthrough;
	case J1939_ERRQUEUE_RX_ABORT:
		if (!(sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE))
			return;
		break;
	default:
		netdev_err(priv->ndev, "Unknown errqueue type %i\n", type);
	}

	skb = j1939_sk_get_timestamping_opt_stats(session, type);
	if (!skb)
		return;

	skb->tstamp = ktime_get_real();

	BUILD_BUG_ON(sizeof(struct sock_exterr_skb) > sizeof(skb->cb));

	serr = SKB_EXT_ERR(skb);
	memset(serr, 0, sizeof(*serr));
	switch (type) {
	case J1939_ERRQUEUE_TX_ACK:
		serr->ee.ee_errno = ENOMSG;
		serr->ee.ee_origin = SO_EE_ORIGIN_TIMESTAMPING;
		serr->ee.ee_info = SCM_TSTAMP_ACK;
		state = "TX ACK";
		break;
	case J1939_ERRQUEUE_TX_SCHED:
		serr->ee.ee_errno = ENOMSG;
		serr->ee.ee_origin = SO_EE_ORIGIN_TIMESTAMPING;
		serr->ee.ee_info = SCM_TSTAMP_SCHED;
		state = "TX SCH";
		break;
	case J1939_ERRQUEUE_TX_ABORT:
		serr->ee.ee_errno = session->err;
		serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
		serr->ee.ee_info = J1939_EE_INFO_TX_ABORT;
		state = "TX ABT";
		break;
	case J1939_ERRQUEUE_RX_RTS:
		serr->ee.ee_errno = ENOMSG;
		serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
		serr->ee.ee_info = J1939_EE_INFO_RX_RTS;
		state = "RX RTS";
		break;
	case J1939_ERRQUEUE_RX_DPO:
		serr->ee.ee_errno = ENOMSG;
		serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
		serr->ee.ee_info = J1939_EE_INFO_RX_DPO;
		state = "RX DPO";
		break;
	case J1939_ERRQUEUE_RX_ABORT:
		serr->ee.ee_errno = session->err;
		serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
		serr->ee.ee_info = J1939_EE_INFO_RX_ABORT;
		state = "RX ABT";
		break;
	}

	serr->opt_stats = true;
	if (sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)
		serr->ee.ee_data = session->tskey;

	netdev_dbg(session->priv->ndev, "%s: 0x%p tskey: %i, state: %s\n",
		   __func__, session, session->tskey, state);
	err = sock_queue_err_skb(sk, skb);

	if (err)
		kfree_skb(skb);
};

void j1939_sk_errqueue(struct j1939_session *session,
		       enum j1939_sk_errqueue_type type)
{
	struct j1939_priv *priv = session->priv;
	struct j1939_sock *jsk;

	if (session->sk) {
		/* send TX notifications to the socket of origin  */
		__j1939_sk_errqueue(session, session->sk, type);
		return;
	}

	/* spread RX notifications to all sockets subscribed to this session */
	spin_lock_bh(&priv->j1939_socks_lock);
	list_for_each_entry(jsk, &priv->j1939_socks, list) {
		if (j1939_sk_recv_match_one(jsk, &session->skcb))
			__j1939_sk_errqueue(session, &jsk->sk, type);
	}
	spin_unlock_bh(&priv->j1939_socks_lock);
};

void j1939_sk_send_loop_abort(struct sock *sk, int err)
{
	sk->sk_err = err;

	sk_error_report(sk);
}

static int j1939_sk_send_loop(struct j1939_priv *priv,  struct sock *sk,
			      struct msghdr *msg, size_t size)

{
	struct j1939_sock *jsk = j1939_sk(sk);
	struct j1939_session *session = j1939_sk_get_incomplete_session(jsk);
	struct sk_buff *skb;
	size_t segment_size, todo_size;
	int ret = 0;

	if (session &&
	    session->total_message_size != session->total_queued_size + size) {
		j1939_session_put(session);
		return -EIO;
	}

	todo_size = size;

	while (todo_size) {
		struct j1939_sk_buff_cb *skcb;

		segment_size = min_t(size_t, J1939_MAX_TP_PACKET_SIZE,
				     todo_size);

		/* Allocate skb for one segment */
		skb = j1939_sk_alloc_skb(priv->ndev, sk, msg, segment_size,
					 &ret);
		if (ret)
			break;

		skcb = j1939_skb_to_cb(skb);

		if (!session) {
			/* at this point the size should be full size
			 * of the session
			 */
			skcb->offset = 0;
			session = j1939_tp_send(priv, skb, size);
			if (IS_ERR(session)) {
				ret = PTR_ERR(session);
				goto kfree_skb;
			}
			if (j1939_sk_queue_session(session)) {
				/* try to activate session if we a
				 * fist in the queue
				 */
				if (!j1939_session_activate(session)) {
					j1939_tp_schedule_txtimer(session, 0);
				} else {
					ret = -EBUSY;
					session->err = ret;
					j1939_sk_queue_drop_all(priv, jsk,
								EBUSY);
					break;
				}
			}
		} else {
			skcb->offset = session->total_queued_size;
			j1939_session_skb_queue(session, skb);
		}

		todo_size -= segment_size;
		session->total_queued_size += segment_size;
	}

	switch (ret) {
	case 0: /* OK */
		if (todo_size)
			netdev_warn(priv->ndev,
				    "no error found and not completely queued?! %zu\n",
				    todo_size);
		ret = size;
		break;
	case -ERESTARTSYS:
		ret = -EINTR;
		fallthrough;
	case -EAGAIN: /* OK */
		if (todo_size != size)
			ret = size - todo_size;
		break;
	default: /* ERROR */
		break;
	}

	if (session)
		j1939_session_put(session);

	return ret;

 kfree_skb:
	kfree_skb(skb);
	return ret;
}

static int j1939_sk_sendmsg(struct socket *sock, struct msghdr *msg,
			    size_t size)
{
	struct sock *sk = sock->sk;
	struct j1939_sock *jsk = j1939_sk(sk);
	struct j1939_priv *priv;
	int ifindex;
	int ret;

	lock_sock(sock->sk);
	/* various socket state tests */
	if (!(jsk->state & J1939_SOCK_BOUND)) {
		ret = -EBADFD;
		goto sendmsg_done;
	}

	priv = jsk->priv;
	ifindex = jsk->ifindex;

	if (!jsk->addr.src_name && jsk->addr.sa == J1939_NO_ADDR) {
		/* no source address assigned yet */
		ret = -EBADFD;
		goto sendmsg_done;
	}

	/* deal with provided destination address info */
	if (msg->msg_name) {
		struct sockaddr_can *addr = msg->msg_name;

		if (msg->msg_namelen < J1939_MIN_NAMELEN) {
			ret = -EINVAL;
			goto sendmsg_done;
		}

		if (addr->can_family != AF_CAN) {
			ret = -EINVAL;
			goto sendmsg_done;
		}

		if (addr->can_ifindex && addr->can_ifindex != ifindex) {
			ret = -EBADFD;
			goto sendmsg_done;
		}

		if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn) &&
		    !j1939_pgn_is_clean_pdu(addr->can_addr.j1939.pgn)) {
			ret = -EINVAL;
			goto sendmsg_done;
		}

		if (!addr->can_addr.j1939.name &&
		    addr->can_addr.j1939.addr == J1939_NO_ADDR &&
		    !sock_flag(sk, SOCK_BROADCAST)) {
			/* broadcast, but SO_BROADCAST not set */
			ret = -EACCES;
			goto sendmsg_done;
		}
	} else {
		if (!jsk->addr.dst_name && jsk->addr.da == J1939_NO_ADDR &&
		    !sock_flag(sk, SOCK_BROADCAST)) {
			/* broadcast, but SO_BROADCAST not set */
			ret = -EACCES;
			goto sendmsg_done;
		}
	}

	ret = j1939_sk_send_loop(priv, sk, msg, size);

sendmsg_done:
	release_sock(sock->sk);

	return ret;
}

void j1939_sk_netdev_event_netdown(struct j1939_priv *priv)
{
	struct j1939_sock *jsk;
	int error_code = ENETDOWN;

	spin_lock_bh(&priv->j1939_socks_lock);
	list_for_each_entry(jsk, &priv->j1939_socks, list) {
		jsk->sk.sk_err = error_code;
		if (!sock_flag(&jsk->sk, SOCK_DEAD))
			sk_error_report(&jsk->sk);

		j1939_sk_queue_drop_all(priv, jsk, error_code);
	}
	spin_unlock_bh(&priv->j1939_socks_lock);
}

static int j1939_sk_no_ioctlcmd(struct socket *sock, unsigned int cmd,
				unsigned long arg)
{
	/* no ioctls for socket layer -> hand it down to NIC layer */
	return -ENOIOCTLCMD;
}

static const struct proto_ops j1939_ops = {
	.family = PF_CAN,
	.release = j1939_sk_release,
	.bind = j1939_sk_bind,
	.connect = j1939_sk_connect,
	.socketpair = sock_no_socketpair,
	.accept = sock_no_accept,
	.getname = j1939_sk_getname,
	.poll = datagram_poll,
	.ioctl = j1939_sk_no_ioctlcmd,
	.listen = sock_no_listen,
	.shutdown = sock_no_shutdown,
	.setsockopt = j1939_sk_setsockopt,
	.getsockopt = j1939_sk_getsockopt,
	.sendmsg = j1939_sk_sendmsg,
	.recvmsg = j1939_sk_recvmsg,
	.mmap = sock_no_mmap,
	.sendpage = sock_no_sendpage,
};

static struct proto j1939_proto __read_mostly = {
	.name = "CAN_J1939",
	.owner = THIS_MODULE,
	.obj_size = sizeof(struct j1939_sock),
	.init = j1939_sk_init,
};

const struct can_proto j1939_can_proto = {
	.type = SOCK_DGRAM,
	.protocol = CAN_J1939,
	.ops = &j1939_ops,
	.prot = &j1939_proto,
};