summaryrefslogtreecommitdiffstats
path: root/net/tipc/bearer.c
blob: 9dfe2bdf1482833624183a1921009a8b3df5e94c (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
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
/*
 * net/tipc/bearer.c: TIPC bearer code
 *
 * Copyright (c) 1996-2006, 2013-2016, Ericsson AB
 * Copyright (c) 2004-2006, 2010-2013, Wind River Systems
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the names of the copyright holders nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * Alternatively, this software may be distributed under the terms of the
 * GNU General Public License ("GPL") version 2 as published by the Free
 * Software Foundation.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <net/sock.h>
#include "core.h"
#include "bearer.h"
#include "link.h"
#include "discover.h"
#include "monitor.h"
#include "bcast.h"
#include "netlink.h"
#include "udp_media.h"
#include "trace.h"
#include "crypto.h"

#define MAX_ADDR_STR 60

static struct tipc_media * const media_info_array[] = {
	&eth_media_info,
#ifdef CONFIG_TIPC_MEDIA_IB
	&ib_media_info,
#endif
#ifdef CONFIG_TIPC_MEDIA_UDP
	&udp_media_info,
#endif
	NULL
};

static struct tipc_bearer *bearer_get(struct net *net, int bearer_id)
{
	struct tipc_net *tn = tipc_net(net);

	return rcu_dereference(tn->bearer_list[bearer_id]);
}

static void bearer_disable(struct net *net, struct tipc_bearer *b);
static int tipc_l2_rcv_msg(struct sk_buff *skb, struct net_device *dev,
			   struct packet_type *pt, struct net_device *orig_dev);

/**
 * tipc_media_find - locates specified media object by name
 * @name: name to locate
 */
struct tipc_media *tipc_media_find(const char *name)
{
	u32 i;

	for (i = 0; media_info_array[i] != NULL; i++) {
		if (!strcmp(media_info_array[i]->name, name))
			break;
	}
	return media_info_array[i];
}

/**
 * media_find_id - locates specified media object by type identifier
 * @type: type identifier to locate
 */
static struct tipc_media *media_find_id(u8 type)
{
	u32 i;

	for (i = 0; media_info_array[i] != NULL; i++) {
		if (media_info_array[i]->type_id == type)
			break;
	}
	return media_info_array[i];
}

/**
 * tipc_media_addr_printf - record media address in print buffer
 * @buf: output buffer
 * @len: output buffer size remaining
 * @a: input media address
 */
int tipc_media_addr_printf(char *buf, int len, struct tipc_media_addr *a)
{
	char addr_str[MAX_ADDR_STR];
	struct tipc_media *m;
	int ret;

	m = media_find_id(a->media_id);

	if (m && !m->addr2str(a, addr_str, sizeof(addr_str)))
		ret = scnprintf(buf, len, "%s(%s)", m->name, addr_str);
	else {
		u32 i;

		ret = scnprintf(buf, len, "UNKNOWN(%u)", a->media_id);
		for (i = 0; i < sizeof(a->value); i++)
			ret += scnprintf(buf + ret, len - ret,
					    "-%x", a->value[i]);
	}
	return ret;
}

/**
 * bearer_name_validate - validate & (optionally) deconstruct bearer name
 * @name: ptr to bearer name string
 * @name_parts: ptr to area for bearer name components (or NULL if not needed)
 *
 * Return: 1 if bearer name is valid, otherwise 0.
 */
static int bearer_name_validate(const char *name,
				struct tipc_bearer_names *name_parts)
{
	char name_copy[TIPC_MAX_BEARER_NAME];
	char *media_name;
	char *if_name;
	u32 media_len;
	u32 if_len;

	/* copy bearer name & ensure length is OK */
	if (strscpy(name_copy, name, TIPC_MAX_BEARER_NAME) < 0)
		return 0;

	/* ensure all component parts of bearer name are present */
	media_name = name_copy;
	if_name = strchr(media_name, ':');
	if (if_name == NULL)
		return 0;
	*(if_name++) = 0;
	media_len = if_name - media_name;
	if_len = strlen(if_name) + 1;

	/* validate component parts of bearer name */
	if ((media_len <= 1) || (media_len > TIPC_MAX_MEDIA_NAME) ||
	    (if_len <= 1) || (if_len > TIPC_MAX_IF_NAME))
		return 0;

	/* return bearer name components, if necessary */
	if (name_parts) {
		strcpy(name_parts->media_name, media_name);
		strcpy(name_parts->if_name, if_name);
	}
	return 1;
}

/**
 * tipc_bearer_find - locates bearer object with matching bearer name
 * @net: the applicable net namespace
 * @name: bearer name to locate
 */
struct tipc_bearer *tipc_bearer_find(struct net *net, const char *name)
{
	struct tipc_net *tn = net_generic(net, tipc_net_id);
	struct tipc_bearer *b;
	u32 i;

	for (i = 0; i < MAX_BEARERS; i++) {
		b = rtnl_dereference(tn->bearer_list[i]);
		if (b && (!strcmp(b->name, name)))
			return b;
	}
	return NULL;
}

/*     tipc_bearer_get_name - get the bearer name from its id.
 *     @net: network namespace
 *     @name: a pointer to the buffer where the name will be stored.
 *     @bearer_id: the id to get the name from.
 */
int tipc_bearer_get_name(struct net *net, char *name, u32 bearer_id)
{
	struct tipc_net *tn = tipc_net(net);
	struct tipc_bearer *b;

	if (bearer_id >= MAX_BEARERS)
		return -EINVAL;

	b = rtnl_dereference(tn->bearer_list[bearer_id]);
	if (!b)
		return -EINVAL;

	strcpy(name, b->name);
	return 0;
}

void tipc_bearer_add_dest(struct net *net, u32 bearer_id, u32 dest)
{
	struct tipc_net *tn = net_generic(net, tipc_net_id);
	struct tipc_bearer *b;

	rcu_read_lock();
	b = rcu_dereference(tn->bearer_list[bearer_id]);
	if (b)
		tipc_disc_add_dest(b->disc);
	rcu_read_unlock();
}

void tipc_bearer_remove_dest(struct net *net, u32 bearer_id, u32 dest)
{
	struct tipc_net *tn = net_generic(net, tipc_net_id);
	struct tipc_bearer *b;

	rcu_read_lock();
	b = rcu_dereference(tn->bearer_list[bearer_id]);
	if (b)
		tipc_disc_remove_dest(b->disc);
	rcu_read_unlock();
}

/**
 * tipc_enable_bearer - enable bearer with the given name
 * @net: the applicable net namespace
 * @name: bearer name to enable
 * @disc_domain: bearer domain
 * @prio: bearer priority
 * @attr: nlattr array
 * @extack: netlink extended ack
 */
static int tipc_enable_bearer(struct net *net, const char *name,
			      u32 disc_domain, u32 prio,
			      struct nlattr *attr[],
			      struct netlink_ext_ack *extack)
{
	struct tipc_net *tn = tipc_net(net);
	struct tipc_bearer_names b_names;
	int with_this_prio = 1;
	struct tipc_bearer *b;
	struct tipc_media *m;
	struct sk_buff *skb;
	int bearer_id = 0;
	int res = -EINVAL;
	char *errstr = "";
	u32 i;

	if (!bearer_name_validate(name, &b_names)) {
		errstr = "illegal name";
		NL_SET_ERR_MSG(extack, "Illegal name");
		goto rejected;
	}

	if (prio > TIPC_MAX_LINK_PRI && prio != TIPC_MEDIA_LINK_PRI) {
		errstr = "illegal priority";
		NL_SET_ERR_MSG(extack, "Illegal priority");
		goto rejected;
	}

	m = tipc_media_find(b_names.media_name);
	if (!m) {
		errstr = "media not registered";
		NL_SET_ERR_MSG(extack, "Media not registered");
		goto rejected;
	}

	if (prio == TIPC_MEDIA_LINK_PRI)
		prio = m->priority;

	/* Check new bearer vs existing ones and find free bearer id if any */
	bearer_id = MAX_BEARERS;
	i = MAX_BEARERS;
	while (i-- != 0) {
		b = rtnl_dereference(tn->bearer_list[i]);
		if (!b) {
			bearer_id = i;
			continue;
		}
		if (!strcmp(name, b->name)) {
			errstr = "already enabled";
			NL_SET_ERR_MSG(extack, "Already enabled");
			goto rejected;
		}

		if (b->priority == prio &&
		    (++with_this_prio > 2)) {
			pr_warn("Bearer <%s>: already 2 bearers with priority %u\n",
				name, prio);

			if (prio == TIPC_MIN_LINK_PRI) {
				errstr = "cannot adjust to lower";
				NL_SET_ERR_MSG(extack, "Cannot adjust to lower");
				goto rejected;
			}

			pr_warn("Bearer <%s>: trying with adjusted priority\n",
				name);
			prio--;
			bearer_id = MAX_BEARERS;
			i = MAX_BEARERS;
			with_this_prio = 1;
		}
	}

	if (bearer_id >= MAX_BEARERS) {
		errstr = "max 3 bearers permitted";
		NL_SET_ERR_MSG(extack, "Max 3 bearers permitted");
		goto rejected;
	}

	b = kzalloc(sizeof(*b), GFP_ATOMIC);
	if (!b)
		return -ENOMEM;

	strcpy(b->name, name);
	b->media = m;
	res = m->enable_media(net, b, attr);
	if (res) {
		kfree(b);
		errstr = "failed to enable media";
		NL_SET_ERR_MSG(extack, "Failed to enable media");
		goto rejected;
	}

	b->identity = bearer_id;
	b->tolerance = m->tolerance;
	b->min_win = m->min_win;
	b->max_win = m->max_win;
	b->domain = disc_domain;
	b->net_plane = bearer_id + 'A';
	b->priority = prio;
	refcount_set(&b->refcnt, 1);

	res = tipc_disc_create(net, b, &b->bcast_addr, &skb);
	if (res) {
		bearer_disable(net, b);
		errstr = "failed to create discoverer";
		NL_SET_ERR_MSG(extack, "Failed to create discoverer");
		goto rejected;
	}

	test_and_set_bit_lock(0, &b->up);
	rcu_assign_pointer(tn->bearer_list[bearer_id], b);
	if (skb)
		tipc_bearer_xmit_skb(net, bearer_id, skb, &b->bcast_addr);

	if (tipc_mon_create(net, bearer_id)) {
		bearer_disable(net, b);
		return -ENOMEM;
	}

	pr_info("Enabled bearer <%s>, priority %u\n", name, prio);

	return res;
rejected:
	pr_warn("Enabling of bearer <%s> rejected, %s\n", name, errstr);
	return res;
}

/**
 * tipc_reset_bearer - Reset all links established over this bearer
 * @net: the applicable net namespace
 * @b: the target bearer
 */
static int tipc_reset_bearer(struct net *net, struct tipc_bearer *b)
{
	pr_info("Resetting bearer <%s>\n", b->name);
	tipc_node_delete_links(net, b->identity);
	tipc_disc_reset(net, b);
	return 0;
}

bool tipc_bearer_hold(struct tipc_bearer *b)
{
	return (b && refcount_inc_not_zero(&b->refcnt));
}

void tipc_bearer_put(struct tipc_bearer *b)
{
	if (b && refcount_dec_and_test(&b->refcnt))
		kfree_rcu(b, rcu);
}

/**
 * bearer_disable - disable this bearer
 * @net: the applicable net namespace
 * @b: the bearer to disable
 *
 * Note: This routine assumes caller holds RTNL lock.
 */
static void bearer_disable(struct net *net, struct tipc_bearer *b)
{
	struct tipc_net *tn = tipc_net(net);
	int bearer_id = b->identity;

	pr_info("Disabling bearer <%s>\n", b->name);
	clear_bit_unlock(0, &b->up);
	tipc_node_delete_links(net, bearer_id);
	b->media->disable_media(b);
	RCU_INIT_POINTER(b->media_ptr, NULL);
	if (b->disc)
		tipc_disc_delete(b->disc);
	RCU_INIT_POINTER(tn->bearer_list[bearer_id], NULL);
	tipc_bearer_put(b);
	tipc_mon_delete(net, bearer_id);
}

int tipc_enable_l2_media(struct net *net, struct tipc_bearer *b,
			 struct nlattr *attr[])
{
	char *dev_name = strchr((const char *)b->name, ':') + 1;
	int hwaddr_len = b->media->hwaddr_len;
	u8 node_id[NODE_ID_LEN] = {0,};
	struct net_device *dev;

	/* Find device with specified name */
	dev = dev_get_by_name(net, dev_name);
	if (!dev)
		return -ENODEV;
	if (tipc_mtu_bad(dev, 0)) {
		dev_put(dev);
		return -EINVAL;
	}
	if (dev == net->loopback_dev) {
		dev_put(dev);
		pr_info("Enabling <%s> not permitted\n", b->name);
		return -EINVAL;
	}

	/* Autoconfigure own node identity if needed */
	if (!tipc_own_id(net) && hwaddr_len <= NODE_ID_LEN) {
		memcpy(node_id, dev->dev_addr, hwaddr_len);
		tipc_net_init(net, node_id, 0);
	}
	if (!tipc_own_id(net)) {
		dev_put(dev);
		pr_warn("Failed to obtain node identity\n");
		return -EINVAL;
	}

	/* Associate TIPC bearer with L2 bearer */
	rcu_assign_pointer(b->media_ptr, dev);
	b->pt.dev = dev;
	b->pt.type = htons(ETH_P_TIPC);
	b->pt.func = tipc_l2_rcv_msg;
	dev_add_pack(&b->pt);
	memset(&b->bcast_addr, 0, sizeof(b->bcast_addr));
	memcpy(b->bcast_addr.value, dev->broadcast, hwaddr_len);
	b->bcast_addr.media_id = b->media->type_id;
	b->bcast_addr.broadcast = TIPC_BROADCAST_SUPPORT;
	b->mtu = dev->mtu;
	b->media->raw2addr(b, &b->addr, (const char *)dev->dev_addr);
	rcu_assign_pointer(dev->tipc_ptr, b);
	return 0;
}

/* tipc_disable_l2_media - detach TIPC bearer from an L2 interface
 * @b: the target bearer
 *
 * Mark L2 bearer as inactive so that incoming buffers are thrown away
 */
void tipc_disable_l2_media(struct tipc_bearer *b)
{
	struct net_device *dev;

	dev = (struct net_device *)rtnl_dereference(b->media_ptr);
	dev_remove_pack(&b->pt);
	RCU_INIT_POINTER(dev->tipc_ptr, NULL);
	synchronize_net();
	dev_put(dev);
}

/**
 * tipc_l2_send_msg - send a TIPC packet out over an L2 interface
 * @net: the associated network namespace
 * @skb: the packet to be sent
 * @b: the bearer through which the packet is to be sent
 * @dest: peer destination address
 */
int tipc_l2_send_msg(struct net *net, struct sk_buff *skb,
		     struct tipc_bearer *b, struct tipc_media_addr *dest)
{
	struct net_device *dev;
	int delta;

	dev = (struct net_device *)rcu_dereference(b->media_ptr);
	if (!dev)
		return 0;

	delta = SKB_DATA_ALIGN(dev->hard_header_len - skb_headroom(skb));
	if ((delta > 0) && pskb_expand_head(skb, delta, 0, GFP_ATOMIC)) {
		kfree_skb(skb);
		return 0;
	}
	skb_reset_network_header(skb);
	skb->dev = dev;
	skb->protocol = htons(ETH_P_TIPC);
	dev_hard_header(skb, dev, ETH_P_TIPC, dest->value,
			dev->dev_addr, skb->len);
	dev_queue_xmit(skb);
	return 0;
}

bool tipc_bearer_bcast_support(struct net *net, u32 bearer_id)
{
	bool supp = false;
	struct tipc_bearer *b;

	rcu_read_lock();
	b = bearer_get(net, bearer_id);
	if (b)
		supp = (b->bcast_addr.broadcast == TIPC_BROADCAST_SUPPORT);
	rcu_read_unlock();
	return supp;
}

int tipc_bearer_mtu(struct net *net, u32 bearer_id)
{
	int mtu = 0;
	struct tipc_bearer *b;

	rcu_read_lock();
	b = rcu_dereference(tipc_net(net)->bearer_list[bearer_id]);
	if (b)
		mtu = b->mtu;
	rcu_read_unlock();
	return mtu;
}

/* tipc_bearer_xmit_skb - sends buffer to destination over bearer
 */
void tipc_bearer_xmit_skb(struct net *net, u32 bearer_id,
			  struct sk_buff *skb,
			  struct tipc_media_addr *dest)
{
	struct tipc_msg *hdr = buf_msg(skb);
	struct tipc_bearer *b;

	rcu_read_lock();
	b = bearer_get(net, bearer_id);
	if (likely(b && (test_bit(0, &b->up) || msg_is_reset(hdr)))) {
#ifdef CONFIG_TIPC_CRYPTO
		tipc_crypto_xmit(net, &skb, b, dest, NULL);
		if (skb)
#endif
			b->media->send_msg(net, skb, b, dest);
	} else {
		kfree_skb(skb);
	}
	rcu_read_unlock();
}

/* tipc_bearer_xmit() -send buffer to destination over bearer
 */
void tipc_bearer_xmit(struct net *net, u32 bearer_id,
		      struct sk_buff_head *xmitq,
		      struct tipc_media_addr *dst,
		      struct tipc_node *__dnode)
{
	struct tipc_bearer *b;
	struct sk_buff *skb, *tmp;

	if (skb_queue_empty(xmitq))
		return;

	rcu_read_lock();
	b = bearer_get(net, bearer_id);
	if (unlikely(!b))
		__skb_queue_purge(xmitq);
	skb_queue_walk_safe(xmitq, skb, tmp) {
		__skb_dequeue(xmitq);
		if (likely(test_bit(0, &b->up) || msg_is_reset(buf_msg(skb)))) {
#ifdef CONFIG_TIPC_CRYPTO
			tipc_crypto_xmit(net, &skb, b, dst, __dnode);
			if (skb)
#endif
				b->media->send_msg(net, skb, b, dst);
		} else {
			kfree_skb(skb);
		}
	}
	rcu_read_unlock();
}

/* tipc_bearer_bc_xmit() - broadcast buffers to all destinations
 */
void tipc_bearer_bc_xmit(struct net *net, u32 bearer_id,
			 struct sk_buff_head *xmitq)
{
	struct tipc_net *tn = tipc_net(net);
	struct tipc_media_addr *dst;
	int net_id = tn->net_id;
	struct tipc_bearer *b;
	struct sk_buff *skb, *tmp;
	struct tipc_msg *hdr;

	rcu_read_lock();
	b = bearer_get(net, bearer_id);
	if (unlikely(!b || !test_bit(0, &b->up)))
		__skb_queue_purge(xmitq);
	skb_queue_walk_safe(xmitq, skb, tmp) {
		hdr = buf_msg(skb);
		msg_set_non_seq(hdr, 1);
		msg_set_mc_netid(hdr, net_id);
		__skb_dequeue(xmitq);
		dst = &b->bcast_addr;
#ifdef CONFIG_TIPC_CRYPTO
		tipc_crypto_xmit(net, &skb, b, dst, NULL);
		if (skb)
#endif
			b->media->send_msg(net, skb, b, dst);
	}
	rcu_read_unlock();
}

/**
 * tipc_l2_rcv_msg - handle incoming TIPC message from an interface
 * @skb: the received message
 * @dev: the net device that the packet was received on
 * @pt: the packet_type structure which was used to register this handler
 * @orig_dev: the original receive net device in case the device is a bond
 *
 * Accept only packets explicitly sent to this node, or broadcast packets;
 * ignores packets sent using interface multicast, and traffic sent to other
 * nodes (which can happen if interface is running in promiscuous mode).
 */
static int tipc_l2_rcv_msg(struct sk_buff *skb, struct net_device *dev,
			   struct packet_type *pt, struct net_device *orig_dev)
{
	struct tipc_bearer *b;

	rcu_read_lock();
	b = rcu_dereference(dev->tipc_ptr) ?:
		rcu_dereference(orig_dev->tipc_ptr);
	if (likely(b && test_bit(0, &b->up) &&
		   (skb->pkt_type <= PACKET_MULTICAST))) {
		skb_mark_not_on_list(skb);
		TIPC_SKB_CB(skb)->flags = 0;
		tipc_rcv(dev_net(b->pt.dev), skb, b);
		rcu_read_unlock();
		return NET_RX_SUCCESS;
	}
	rcu_read_unlock();
	kfree_skb(skb);
	return NET_RX_DROP;
}

/**
 * tipc_l2_device_event - handle device events from network device
 * @nb: the context of the notification
 * @evt: the type of event
 * @ptr: the net device that the event was on
 *
 * This function is called by the Ethernet driver in case of link
 * change event.
 */
static int tipc_l2_device_event(struct notifier_block *nb, unsigned long evt,
				void *ptr)
{
	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
	struct net *net = dev_net(dev);
	struct tipc_bearer *b;

	b = rtnl_dereference(dev->tipc_ptr);
	if (!b)
		return NOTIFY_DONE;

	trace_tipc_l2_device_event(dev, b, evt);
	switch (evt) {
	case NETDEV_CHANGE:
		if (netif_carrier_ok(dev) && netif_oper_up(dev)) {
			test_and_set_bit_lock(0, &b->up);
			break;
		}
		fallthrough;
	case NETDEV_GOING_DOWN:
		clear_bit_unlock(0, &b->up);
		tipc_reset_bearer(net, b);
		break;
	case NETDEV_UP:
		test_and_set_bit_lock(0, &b->up);
		break;
	case NETDEV_CHANGEMTU:
		if (tipc_mtu_bad(dev, 0)) {
			bearer_disable(net, b);
			break;
		}
		b->mtu = dev->mtu;
		tipc_reset_bearer(net, b);
		break;
	case NETDEV_CHANGEADDR:
		b->media->raw2addr(b, &b->addr,
				   (const char *)dev->dev_addr);
		tipc_reset_bearer(net, b);
		break;
	case NETDEV_UNREGISTER:
	case NETDEV_CHANGENAME:
		bearer_disable(net, b);
		break;
	}
	return NOTIFY_OK;
}

static struct notifier_block notifier = {
	.notifier_call  = tipc_l2_device_event,
	.priority	= 0,
};

int tipc_bearer_setup(void)
{
	return register_netdevice_notifier(&notifier);
}

void tipc_bearer_cleanup(void)
{
	unregister_netdevice_notifier(&notifier);
}

void tipc_bearer_stop(struct net *net)
{
	struct tipc_net *tn = net_generic(net, tipc_net_id);
	struct tipc_bearer *b;
	u32 i;

	for (i = 0; i < MAX_BEARERS; i++) {
		b = rtnl_dereference(tn->bearer_list[i]);
		if (b) {
			bearer_disable(net, b);
			tn->bearer_list[i] = NULL;
		}
	}
}

void tipc_clone_to_loopback(struct net *net, struct sk_buff_head *pkts)
{
	struct net_device *dev = net->loopback_dev;
	struct sk_buff *skb, *_skb;
	int exp;

	skb_queue_walk(pkts, _skb) {
		skb = pskb_copy(_skb, GFP_ATOMIC);
		if (!skb)
			continue;

		exp = SKB_DATA_ALIGN(dev->hard_header_len - skb_headroom(skb));
		if (exp > 0 && pskb_expand_head(skb, exp, 0, GFP_ATOMIC)) {
			kfree_skb(skb);
			continue;
		}

		skb_reset_network_header(skb);
		dev_hard_header(skb, dev, ETH_P_TIPC, dev->dev_addr,
				dev->dev_addr, skb->len);
		skb->dev = dev;
		skb->pkt_type = PACKET_HOST;
		skb->ip_summed = CHECKSUM_UNNECESSARY;
		skb->protocol = eth_type_trans(skb, dev);
		netif_rx(skb);
	}
}

static int tipc_loopback_rcv_pkt(struct sk_buff *skb, struct net_device *dev,
				 struct packet_type *pt, struct net_device *od)
{
	consume_skb(skb);
	return NET_RX_SUCCESS;
}

int tipc_attach_loopback(struct net *net)
{
	struct net_device *dev = net->loopback_dev;
	struct tipc_net *tn = tipc_net(net);

	if (!dev)
		return -ENODEV;

	dev_hold_track(dev, &tn->loopback_pt.dev_tracker, GFP_KERNEL);
	tn->loopback_pt.dev = dev;
	tn->loopback_pt.type = htons(ETH_P_TIPC);
	tn->loopback_pt.func = tipc_loopback_rcv_pkt;
	dev_add_pack(&tn->loopback_pt);
	return 0;
}

void tipc_detach_loopback(struct net *net)
{
	struct tipc_net *tn = tipc_net(net);

	dev_remove_pack(&tn->loopback_pt);
	dev_put_track(net->loopback_dev, &tn->loopback_pt.dev_tracker);
}

/* Caller should hold rtnl_lock to protect the bearer */
static int __tipc_nl_add_bearer(struct tipc_nl_msg *msg,
				struct tipc_bearer *bearer, int nlflags)
{
	void *hdr;
	struct nlattr *attrs;
	struct nlattr *prop;

	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
			  nlflags, TIPC_NL_BEARER_GET);
	if (!hdr)
		return -EMSGSIZE;

	attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_BEARER);
	if (!attrs)
		goto msg_full;

	if (nla_put_string(msg->skb, TIPC_NLA_BEARER_NAME, bearer->name))
		goto attr_msg_full;

	prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_BEARER_PROP);
	if (!prop)
		goto prop_msg_full;
	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, bearer->priority))
		goto prop_msg_full;
	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, bearer->tolerance))
		goto prop_msg_full;
	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bearer->max_win))
		goto prop_msg_full;
	if (bearer->media->type_id == TIPC_MEDIA_TYPE_UDP)
		if (nla_put_u32(msg->skb, TIPC_NLA_PROP_MTU, bearer->mtu))
			goto prop_msg_full;

	nla_nest_end(msg->skb, prop);

#ifdef CONFIG_TIPC_MEDIA_UDP
	if (bearer->media->type_id == TIPC_MEDIA_TYPE_UDP) {
		if (tipc_udp_nl_add_bearer_data(msg, bearer))
			goto attr_msg_full;
	}
#endif

	nla_nest_end(msg->skb, attrs);
	genlmsg_end(msg->skb, hdr);

	return 0;

prop_msg_full:
	nla_nest_cancel(msg->skb, prop);
attr_msg_full:
	nla_nest_cancel(msg->skb, attrs);
msg_full:
	genlmsg_cancel(msg->skb, hdr);

	return -EMSGSIZE;
}

int tipc_nl_bearer_dump(struct sk_buff *skb, struct netlink_callback *cb)
{
	int err;
	int i = cb->args[0];
	struct tipc_bearer *bearer;
	struct tipc_nl_msg msg;
	struct net *net = sock_net(skb->sk);
	struct tipc_net *tn = net_generic(net, tipc_net_id);

	if (i == MAX_BEARERS)
		return 0;

	msg.skb = skb;
	msg.portid = NETLINK_CB(cb->skb).portid;
	msg.seq = cb->nlh->nlmsg_seq;

	rtnl_lock();
	for (i = 0; i < MAX_BEARERS; i++) {
		bearer = rtnl_dereference(tn->bearer_list[i]);
		if (!bearer)
			continue;

		err = __tipc_nl_add_bearer(&msg, bearer, NLM_F_MULTI);
		if (err)
			break;
	}
	rtnl_unlock();

	cb->args[0] = i;
	return skb->len;
}

int tipc_nl_bearer_get(struct sk_buff *skb, struct genl_info *info)
{
	int err;
	char *name;
	struct sk_buff *rep;
	struct tipc_bearer *bearer;
	struct tipc_nl_msg msg;
	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
	struct net *net = genl_info_net(info);

	if (!info->attrs[TIPC_NLA_BEARER])
		return -EINVAL;

	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_BEARER_MAX,
					  info->attrs[TIPC_NLA_BEARER],
					  tipc_nl_bearer_policy, info->extack);
	if (err)
		return err;

	if (!attrs[TIPC_NLA_BEARER_NAME])
		return -EINVAL;
	name = nla_data(attrs[TIPC_NLA_BEARER_NAME]);

	rep = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
	if (!rep)
		return -ENOMEM;

	msg.skb = rep;
	msg.portid = info->snd_portid;
	msg.seq = info->snd_seq;

	rtnl_lock();
	bearer = tipc_bearer_find(net, name);
	if (!bearer) {
		err = -EINVAL;
		NL_SET_ERR_MSG(info->extack, "Bearer not found");
		goto err_out;
	}

	err = __tipc_nl_add_bearer(&msg, bearer, 0);
	if (err)
		goto err_out;
	rtnl_unlock();

	return genlmsg_reply(rep, info);
err_out:
	rtnl_unlock();
	nlmsg_free(rep);

	return err;
}

int __tipc_nl_bearer_disable(struct sk_buff *skb, struct genl_info *info)
{
	int err;
	char *name;
	struct tipc_bearer *bearer;
	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
	struct net *net = sock_net(skb->sk);

	if (!info->attrs[TIPC_NLA_BEARER])
		return -EINVAL;

	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_BEARER_MAX,
					  info->attrs[TIPC_NLA_BEARER],
					  tipc_nl_bearer_policy, info->extack);
	if (err)
		return err;

	if (!attrs[TIPC_NLA_BEARER_NAME])
		return -EINVAL;

	name = nla_data(attrs[TIPC_NLA_BEARER_NAME]);

	bearer = tipc_bearer_find(net, name);
	if (!bearer) {
		NL_SET_ERR_MSG(info->extack, "Bearer not found");
		return -EINVAL;
	}

	bearer_disable(net, bearer);

	return 0;
}

int tipc_nl_bearer_disable(struct sk_buff *skb, struct genl_info *info)
{
	int err;

	rtnl_lock();
	err = __tipc_nl_bearer_disable(skb, info);
	rtnl_unlock();

	return err;
}

int __tipc_nl_bearer_enable(struct sk_buff *skb, struct genl_info *info)
{
	int err;
	char *bearer;
	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
	struct net *net = sock_net(skb->sk);
	u32 domain = 0;
	u32 prio;

	prio = TIPC_MEDIA_LINK_PRI;

	if (!info->attrs[TIPC_NLA_BEARER])
		return -EINVAL;

	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_BEARER_MAX,
					  info->attrs[TIPC_NLA_BEARER],
					  tipc_nl_bearer_policy, info->extack);
	if (err)
		return err;

	if (!attrs[TIPC_NLA_BEARER_NAME])
		return -EINVAL;

	bearer = nla_data(attrs[TIPC_NLA_BEARER_NAME]);

	if (attrs[TIPC_NLA_BEARER_DOMAIN])
		domain = nla_get_u32(attrs[TIPC_NLA_BEARER_DOMAIN]);

	if (attrs[TIPC_NLA_BEARER_PROP]) {
		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];

		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_BEARER_PROP],
					      props);
		if (err)
			return err;

		if (props[TIPC_NLA_PROP_PRIO])
			prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
	}

	return tipc_enable_bearer(net, bearer, domain, prio, attrs,
				  info->extack);
}

int tipc_nl_bearer_enable(struct sk_buff *skb, struct genl_info *info)
{
	int err;

	rtnl_lock();
	err = __tipc_nl_bearer_enable(skb, info);
	rtnl_unlock();

	return err;
}

int tipc_nl_bearer_add(struct sk_buff *skb, struct genl_info *info)
{
	int err;
	char *name;
	struct tipc_bearer *b;
	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
	struct net *net = sock_net(skb->sk);

	if (!info->attrs[TIPC_NLA_BEARER])
		return -EINVAL;

	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_BEARER_MAX,
					  info->attrs[TIPC_NLA_BEARER],
					  tipc_nl_bearer_policy, info->extack);
	if (err)
		return err;

	if (!attrs[TIPC_NLA_BEARER_NAME])
		return -EINVAL;
	name = nla_data(attrs[TIPC_NLA_BEARER_NAME]);

	rtnl_lock();
	b = tipc_bearer_find(net, name);
	if (!b) {
		rtnl_unlock();
		NL_SET_ERR_MSG(info->extack, "Bearer not found");
		return -EINVAL;
	}

#ifdef CONFIG_TIPC_MEDIA_UDP
	if (attrs[TIPC_NLA_BEARER_UDP_OPTS]) {
		err = tipc_udp_nl_bearer_add(b,
					     attrs[TIPC_NLA_BEARER_UDP_OPTS]);
		if (err) {
			rtnl_unlock();
			return err;
		}
	}
#endif
	rtnl_unlock();

	return 0;
}

int __tipc_nl_bearer_set(struct sk_buff *skb, struct genl_info *info)
{
	struct tipc_bearer *b;
	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];
	struct net *net = sock_net(skb->sk);
	char *name;
	int err;

	if (!info->attrs[TIPC_NLA_BEARER])
		return -EINVAL;

	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_BEARER_MAX,
					  info->attrs[TIPC_NLA_BEARER],
					  tipc_nl_bearer_policy, info->extack);
	if (err)
		return err;

	if (!attrs[TIPC_NLA_BEARER_NAME])
		return -EINVAL;
	name = nla_data(attrs[TIPC_NLA_BEARER_NAME]);

	b = tipc_bearer_find(net, name);
	if (!b) {
		NL_SET_ERR_MSG(info->extack, "Bearer not found");
		return -EINVAL;
	}

	if (attrs[TIPC_NLA_BEARER_PROP]) {
		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];

		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_BEARER_PROP],
					      props);
		if (err)
			return err;

		if (props[TIPC_NLA_PROP_TOL]) {
			b->tolerance = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
			tipc_node_apply_property(net, b, TIPC_NLA_PROP_TOL);
		}
		if (props[TIPC_NLA_PROP_PRIO])
			b->priority = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
		if (props[TIPC_NLA_PROP_WIN])
			b->max_win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
		if (props[TIPC_NLA_PROP_MTU]) {
			if (b->media->type_id != TIPC_MEDIA_TYPE_UDP) {
				NL_SET_ERR_MSG(info->extack,
					       "MTU property is unsupported");
				return -EINVAL;
			}
#ifdef CONFIG_TIPC_MEDIA_UDP
			if (tipc_udp_mtu_bad(nla_get_u32
					     (props[TIPC_NLA_PROP_MTU]))) {
				NL_SET_ERR_MSG(info->extack,
					       "MTU value is out-of-range");
				return -EINVAL;
			}
			b->mtu = nla_get_u32(props[TIPC_NLA_PROP_MTU]);
			tipc_node_apply_property(net, b, TIPC_NLA_PROP_MTU);
#endif
		}
	}

	return 0;
}

int tipc_nl_bearer_set(struct sk_buff *skb, struct genl_info *info)
{
	int err;

	rtnl_lock();
	err = __tipc_nl_bearer_set(skb, info);
	rtnl_unlock();

	return err;
}

static int __tipc_nl_add_media(struct tipc_nl_msg *msg,
			       struct tipc_media *media, int nlflags)
{
	void *hdr;
	struct nlattr *attrs;
	struct nlattr *prop;

	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
			  nlflags, TIPC_NL_MEDIA_GET);
	if (!hdr)
		return -EMSGSIZE;

	attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_MEDIA);
	if (!attrs)
		goto msg_full;

	if (nla_put_string(msg->skb, TIPC_NLA_MEDIA_NAME, media->name))
		goto attr_msg_full;

	prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_MEDIA_PROP);
	if (!prop)
		goto prop_msg_full;
	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, media->priority))
		goto prop_msg_full;
	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, media->tolerance))
		goto prop_msg_full;
	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, media->max_win))
		goto prop_msg_full;
	if (media->type_id == TIPC_MEDIA_TYPE_UDP)
		if (nla_put_u32(msg->skb, TIPC_NLA_PROP_MTU, media->mtu))
			goto prop_msg_full;

	nla_nest_end(msg->skb, prop);
	nla_nest_end(msg->skb, attrs);
	genlmsg_end(msg->skb, hdr);

	return 0;

prop_msg_full:
	nla_nest_cancel(msg->skb, prop);
attr_msg_full:
	nla_nest_cancel(msg->skb, attrs);
msg_full:
	genlmsg_cancel(msg->skb, hdr);

	return -EMSGSIZE;
}

int tipc_nl_media_dump(struct sk_buff *skb, struct netlink_callback *cb)
{
	int err;
	int i = cb->args[0];
	struct tipc_nl_msg msg;

	if (i == MAX_MEDIA)
		return 0;

	msg.skb = skb;
	msg.portid = NETLINK_CB(cb->skb).portid;
	msg.seq = cb->nlh->nlmsg_seq;

	rtnl_lock();
	for (; media_info_array[i] != NULL; i++) {
		err = __tipc_nl_add_media(&msg, media_info_array[i],
					  NLM_F_MULTI);
		if (err)
			break;
	}
	rtnl_unlock();

	cb->args[0] = i;
	return skb->len;
}

int tipc_nl_media_get(struct sk_buff *skb, struct genl_info *info)
{
	int err;
	char *name;
	struct tipc_nl_msg msg;
	struct tipc_media *media;
	struct sk_buff *rep;
	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];

	if (!info->attrs[TIPC_NLA_MEDIA])
		return -EINVAL;

	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_MEDIA_MAX,
					  info->attrs[TIPC_NLA_MEDIA],
					  tipc_nl_media_policy, info->extack);
	if (err)
		return err;

	if (!attrs[TIPC_NLA_MEDIA_NAME])
		return -EINVAL;
	name = nla_data(attrs[TIPC_NLA_MEDIA_NAME]);

	rep = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
	if (!rep)
		return -ENOMEM;

	msg.skb = rep;
	msg.portid = info->snd_portid;
	msg.seq = info->snd_seq;

	rtnl_lock();
	media = tipc_media_find(name);
	if (!media) {
		NL_SET_ERR_MSG(info->extack, "Media not found");
		err = -EINVAL;
		goto err_out;
	}

	err = __tipc_nl_add_media(&msg, media, 0);
	if (err)
		goto err_out;
	rtnl_unlock();

	return genlmsg_reply(rep, info);
err_out:
	rtnl_unlock();
	nlmsg_free(rep);

	return err;
}

int __tipc_nl_media_set(struct sk_buff *skb, struct genl_info *info)
{
	int err;
	char *name;
	struct tipc_media *m;
	struct nlattr *attrs[TIPC_NLA_BEARER_MAX + 1];

	if (!info->attrs[TIPC_NLA_MEDIA])
		return -EINVAL;

	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_MEDIA_MAX,
					  info->attrs[TIPC_NLA_MEDIA],
					  tipc_nl_media_policy, info->extack);

	if (!attrs[TIPC_NLA_MEDIA_NAME])
		return -EINVAL;
	name = nla_data(attrs[TIPC_NLA_MEDIA_NAME]);

	m = tipc_media_find(name);
	if (!m) {
		NL_SET_ERR_MSG(info->extack, "Media not found");
		return -EINVAL;
	}
	if (attrs[TIPC_NLA_MEDIA_PROP]) {
		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];

		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_MEDIA_PROP],
					      props);
		if (err)
			return err;

		if (props[TIPC_NLA_PROP_TOL])
			m->tolerance = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
		if (props[TIPC_NLA_PROP_PRIO])
			m->priority = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
		if (props[TIPC_NLA_PROP_WIN])
			m->max_win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
		if (props[TIPC_NLA_PROP_MTU]) {
			if (m->type_id != TIPC_MEDIA_TYPE_UDP) {
				NL_SET_ERR_MSG(info->extack,
					       "MTU property is unsupported");
				return -EINVAL;
			}
#ifdef CONFIG_TIPC_MEDIA_UDP
			if (tipc_udp_mtu_bad(nla_get_u32
					     (props[TIPC_NLA_PROP_MTU]))) {
				NL_SET_ERR_MSG(info->extack,
					       "MTU value is out-of-range");
				return -EINVAL;
			}
			m->mtu = nla_get_u32(props[TIPC_NLA_PROP_MTU]);
#endif
		}
	}

	return 0;
}

int tipc_nl_media_set(struct sk_buff *skb, struct genl_info *info)
{
	int err;

	rtnl_lock();
	err = __tipc_nl_media_set(skb, info);
	rtnl_unlock();

	return err;
}