aboutsummaryrefslogtreecommitdiffstats
path: root/net/decnet/dn_dev.c
blob: 66e266fb5908b4976448da87ddc74d509c25b10f (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
/*
 * DECnet       An implementation of the DECnet protocol suite for the LINUX
 *              operating system.  DECnet is implemented using the  BSD Socket
 *              interface as the means of communication with the user level.
 *
 *              DECnet Device Layer
 *
 * Authors:     Steve Whitehouse <SteveW@ACM.org>
 *              Eduardo Marcelo Serrat <emserrat@geocities.com>
 *
 * Changes:
 *          Steve Whitehouse : Devices now see incoming frames so they
 *                             can mark on who it came from.
 *          Steve Whitehouse : Fixed bug in creating neighbours. Each neighbour
 *                             can now have a device specific setup func.
 *          Steve Whitehouse : Added /proc/sys/net/decnet/conf/<dev>/
 *          Steve Whitehouse : Fixed bug which sometimes killed timer
 *          Steve Whitehouse : Multiple ifaddr support
 *          Steve Whitehouse : SIOCGIFCONF is now a compile time option
 *          Steve Whitehouse : /proc/sys/net/decnet/conf/<sys>/forwarding
 *          Steve Whitehouse : Removed timer1 - it's a user space issue now
 *         Patrick Caulfield : Fixed router hello message format
 *          Steve Whitehouse : Got rid of constant sizes for blksize for
 *                             devices. All mtu based now.
 */

#include <linux/capability.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/net.h>
#include <linux/netdevice.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/timer.h>
#include <linux/string.h>
#include <linux/if_addr.h>
#include <linux/if_arp.h>
#include <linux/if_ether.h>
#include <linux/skbuff.h>
#include <linux/sysctl.h>
#include <linux/notifier.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <net/net_namespace.h>
#include <net/neighbour.h>
#include <net/dst.h>
#include <net/flow.h>
#include <net/fib_rules.h>
#include <net/netlink.h>
#include <net/dn.h>
#include <net/dn_dev.h>
#include <net/dn_route.h>
#include <net/dn_neigh.h>
#include <net/dn_fib.h>

#define DN_IFREQ_SIZE (sizeof(struct ifreq) - sizeof(struct sockaddr) + sizeof(struct sockaddr_dn))

static char dn_rt_all_end_mcast[ETH_ALEN] = {0xAB,0x00,0x00,0x04,0x00,0x00};
static char dn_rt_all_rt_mcast[ETH_ALEN]  = {0xAB,0x00,0x00,0x03,0x00,0x00};
static char dn_hiord[ETH_ALEN]            = {0xAA,0x00,0x04,0x00,0x00,0x00};
static unsigned char dn_eco_version[3]    = {0x02,0x00,0x00};

extern struct neigh_table dn_neigh_table;

/*
 * decnet_address is kept in network order.
 */
__le16 decnet_address = 0;

static DEFINE_RWLOCK(dndev_lock);
static struct net_device *decnet_default_device;
static BLOCKING_NOTIFIER_HEAD(dnaddr_chain);

static struct dn_dev *dn_dev_create(struct net_device *dev, int *err);
static void dn_dev_delete(struct net_device *dev);
static void dn_ifaddr_notify(int event, struct dn_ifaddr *ifa);

static int dn_eth_up(struct net_device *);
static void dn_eth_down(struct net_device *);
static void dn_send_brd_hello(struct net_device *dev, struct dn_ifaddr *ifa);
static void dn_send_ptp_hello(struct net_device *dev, struct dn_ifaddr *ifa);

static struct dn_dev_parms dn_dev_list[] =  {
{
	.type =		ARPHRD_ETHER, /* Ethernet */
	.mode =		DN_DEV_BCAST,
	.state =	DN_DEV_S_RU,
	.t2 =		1,
	.t3 =		10,
	.name =		"ethernet",
	.ctl_name =	NET_DECNET_CONF_ETHER,
	.up =		dn_eth_up,
	.down = 	dn_eth_down,
	.timer3 =	dn_send_brd_hello,
},
{
	.type =		ARPHRD_IPGRE, /* DECnet tunneled over GRE in IP */
	.mode =		DN_DEV_BCAST,
	.state =	DN_DEV_S_RU,
	.t2 =		1,
	.t3 =		10,
	.name =		"ipgre",
	.ctl_name =	NET_DECNET_CONF_GRE,
	.timer3 =	dn_send_brd_hello,
},
#if 0
{
	.type =		ARPHRD_X25, /* Bog standard X.25 */
	.mode =		DN_DEV_UCAST,
	.state =	DN_DEV_S_DS,
	.t2 =		1,
	.t3 =		120,
	.name =		"x25",
	.ctl_name =	NET_DECNET_CONF_X25,
	.timer3 =	dn_send_ptp_hello,
},
#endif
#if 0
{
	.type =		ARPHRD_PPP, /* DECnet over PPP */
	.mode =		DN_DEV_BCAST,
	.state =	DN_DEV_S_RU,
	.t2 =		1,
	.t3 =		10,
	.name =		"ppp",
	.ctl_name =	NET_DECNET_CONF_PPP,
	.timer3 =	dn_send_brd_hello,
},
#endif
{
	.type =		ARPHRD_DDCMP, /* DECnet over DDCMP */
	.mode =		DN_DEV_UCAST,
	.state =	DN_DEV_S_DS,
	.t2 =		1,
	.t3 =		120,
	.name =		"ddcmp",
	.ctl_name =	NET_DECNET_CONF_DDCMP,
	.timer3 =	dn_send_ptp_hello,
},
{
	.type =		ARPHRD_LOOPBACK, /* Loopback interface - always last */
	.mode =		DN_DEV_BCAST,
	.state =	DN_DEV_S_RU,
	.t2 =		1,
	.t3 =		10,
	.name =		"loopback",
	.ctl_name =	NET_DECNET_CONF_LOOPBACK,
	.timer3 =	dn_send_brd_hello,
}
};

#define DN_DEV_LIST_SIZE ARRAY_SIZE(dn_dev_list)

#define DN_DEV_PARMS_OFFSET(x) ((int) ((char *) &((struct dn_dev_parms *)0)->x))

#ifdef CONFIG_SYSCTL

static int min_t2[] = { 1 };
static int max_t2[] = { 60 }; /* No max specified, but this seems sensible */
static int min_t3[] = { 1 };
static int max_t3[] = { 8191 }; /* Must fit in 16 bits when multiplied by BCT3MULT or T3MULT */

static int min_priority[1];
static int max_priority[] = { 127 }; /* From DECnet spec */

static int dn_forwarding_proc(ctl_table *, int, struct file *,
			void __user *, size_t *, loff_t *);
static int dn_forwarding_sysctl(ctl_table *table, int __user *name, int nlen,
			void __user *oldval, size_t __user *oldlenp,
			void __user *newval, size_t newlen);

static struct dn_dev_sysctl_table {
	struct ctl_table_header *sysctl_header;
	ctl_table dn_dev_vars[5];
	ctl_table dn_dev_dev[2];
	ctl_table dn_dev_conf_dir[2];
	ctl_table dn_dev_proto_dir[2];
	ctl_table dn_dev_root_dir[2];
} dn_dev_sysctl = {
	NULL,
	{
	{
		.ctl_name = NET_DECNET_CONF_DEV_FORWARDING,
		.procname = "forwarding",
		.data = (void *)DN_DEV_PARMS_OFFSET(forwarding),
		.maxlen = sizeof(int),
		.mode = 0644,
		.proc_handler = dn_forwarding_proc,
		.strategy = dn_forwarding_sysctl,
	},
	{
		.ctl_name = NET_DECNET_CONF_DEV_PRIORITY,
		.procname = "priority",
		.data = (void *)DN_DEV_PARMS_OFFSET(priority),
		.maxlen = sizeof(int),
		.mode = 0644,
		.proc_handler = proc_dointvec_minmax,
		.strategy = sysctl_intvec,
		.extra1 = &min_priority,
		.extra2 = &max_priority
	},
	{
		.ctl_name = NET_DECNET_CONF_DEV_T2,
		.procname = "t2",
		.data = (void *)DN_DEV_PARMS_OFFSET(t2),
		.maxlen = sizeof(int),
		.mode = 0644,
		.proc_handler = proc_dointvec_minmax,
		.strategy = sysctl_intvec,
		.extra1 = &min_t2,
		.extra2 = &max_t2
	},
	{
		.ctl_name = NET_DECNET_CONF_DEV_T3,
		.procname = "t3",
		.data = (void *)DN_DEV_PARMS_OFFSET(t3),
		.maxlen = sizeof(int),
		.mode = 0644,
		.proc_handler = proc_dointvec_minmax,
		.strategy = sysctl_intvec,
		.extra1 = &min_t3,
		.extra2 = &max_t3
	},
	{0}
	},
	{{
		.ctl_name = 0,
		.procname = "",
		.mode = 0555,
		.child = dn_dev_sysctl.dn_dev_vars
	}, {0}},
	{{
		.ctl_name = NET_DECNET_CONF,
		.procname = "conf",
		.mode = 0555,
		.child = dn_dev_sysctl.dn_dev_dev
	}, {0}},
	{{
		.ctl_name = NET_DECNET,
		.procname = "decnet",
		.mode = 0555,
		.child = dn_dev_sysctl.dn_dev_conf_dir
	}, {0}},
	{{
		.ctl_name = CTL_NET,
		.procname = "net",
		.mode = 0555,
		.child = dn_dev_sysctl.dn_dev_proto_dir
	}, {0}}
};

static void dn_dev_sysctl_register(struct net_device *dev, struct dn_dev_parms *parms)
{
	struct dn_dev_sysctl_table *t;
	int i;

	t = kmemdup(&dn_dev_sysctl, sizeof(*t), GFP_KERNEL);
	if (t == NULL)
		return;

	for(i = 0; i < ARRAY_SIZE(t->dn_dev_vars) - 1; i++) {
		long offset = (long)t->dn_dev_vars[i].data;
		t->dn_dev_vars[i].data = ((char *)parms) + offset;
	}

	if (dev) {
		t->dn_dev_dev[0].procname = dev->name;
		t->dn_dev_dev[0].ctl_name = dev->ifindex;
	} else {
		t->dn_dev_dev[0].procname = parms->name;
		t->dn_dev_dev[0].ctl_name = parms->ctl_name;
	}

	t->dn_dev_dev[0].child = t->dn_dev_vars;
	t->dn_dev_conf_dir[0].child = t->dn_dev_dev;
	t->dn_dev_proto_dir[0].child = t->dn_dev_conf_dir;
	t->dn_dev_root_dir[0].child = t->dn_dev_proto_dir;
	t->dn_dev_vars[0].extra1 = (void *)dev;

	t->sysctl_header = register_sysctl_table(t->dn_dev_root_dir);
	if (t->sysctl_header == NULL)
		kfree(t);
	else
		parms->sysctl = t;
}

static void dn_dev_sysctl_unregister(struct dn_dev_parms *parms)
{
	if (parms->sysctl) {
		struct dn_dev_sysctl_table *t = parms->sysctl;
		parms->sysctl = NULL;
		unregister_sysctl_table(t->sysctl_header);
		kfree(t);
	}
}

static int dn_forwarding_proc(ctl_table *table, int write,
				struct file *filep,
				void __user *buffer,
				size_t *lenp, loff_t *ppos)
{
#ifdef CONFIG_DECNET_ROUTER
	struct net_device *dev = table->extra1;
	struct dn_dev *dn_db;
	int err;
	int tmp, old;

	if (table->extra1 == NULL)
		return -EINVAL;

	dn_db = dev->dn_ptr;
	old = dn_db->parms.forwarding;

	err = proc_dointvec(table, write, filep, buffer, lenp, ppos);

	if ((err >= 0) && write) {
		if (dn_db->parms.forwarding < 0)
			dn_db->parms.forwarding = 0;
		if (dn_db->parms.forwarding > 2)
			dn_db->parms.forwarding = 2;
		/*
		 * What an ugly hack this is... its works, just. It
		 * would be nice if sysctl/proc were just that little
		 * bit more flexible so I don't have to write a special
		 * routine, or suffer hacks like this - SJW
		 */
		tmp = dn_db->parms.forwarding;
		dn_db->parms.forwarding = old;
		if (dn_db->parms.down)
			dn_db->parms.down(dev);
		dn_db->parms.forwarding = tmp;
		if (dn_db->parms.up)
			dn_db->parms.up(dev);
	}

	return err;
#else
	return -EINVAL;
#endif
}

static int dn_forwarding_sysctl(ctl_table *table, int __user *name, int nlen,
			void __user *oldval, size_t __user *oldlenp,
			void __user *newval, size_t newlen)
{
#ifdef CONFIG_DECNET_ROUTER
	struct net_device *dev = table->extra1;
	struct dn_dev *dn_db;
	int value;

	if (table->extra1 == NULL)
		return -EINVAL;

	dn_db = dev->dn_ptr;

	if (newval && newlen) {
		if (newlen != sizeof(int))
			return -EINVAL;

		if (get_user(value, (int __user *)newval))
			return -EFAULT;
		if (value < 0)
			return -EINVAL;
		if (value > 2)
			return -EINVAL;

		if (dn_db->parms.down)
			dn_db->parms.down(dev);
		dn_db->parms.forwarding = value;
		if (dn_db->parms.up)
			dn_db->parms.up(dev);
	}

	return 0;
#else
	return -EINVAL;
#endif
}

#else /* CONFIG_SYSCTL */
static void dn_dev_sysctl_unregister(struct dn_dev_parms *parms)
{
}
static void dn_dev_sysctl_register(struct net_device *dev, struct dn_dev_parms *parms)
{
}

#endif /* CONFIG_SYSCTL */

static inline __u16 mtu2blksize(struct net_device *dev)
{
	u32 blksize = dev->mtu;
	if (blksize > 0xffff)
		blksize = 0xffff;

	if (dev->type == ARPHRD_ETHER ||
	    dev->type == ARPHRD_PPP ||
	    dev->type == ARPHRD_IPGRE ||
	    dev->type == ARPHRD_LOOPBACK)
		blksize -= 2;

	return (__u16)blksize;
}

static struct dn_ifaddr *dn_dev_alloc_ifa(void)
{
	struct dn_ifaddr *ifa;

	ifa = kzalloc(sizeof(*ifa), GFP_KERNEL);

	return ifa;
}

static __inline__ void dn_dev_free_ifa(struct dn_ifaddr *ifa)
{
	kfree(ifa);
}

static void dn_dev_del_ifa(struct dn_dev *dn_db, struct dn_ifaddr **ifap, int destroy)
{
	struct dn_ifaddr *ifa1 = *ifap;
	unsigned char mac_addr[6];
	struct net_device *dev = dn_db->dev;

	ASSERT_RTNL();

	*ifap = ifa1->ifa_next;

	if (dn_db->dev->type == ARPHRD_ETHER) {
		if (ifa1->ifa_local != dn_eth2dn(dev->dev_addr)) {
			dn_dn2eth(mac_addr, ifa1->ifa_local);
			dev_mc_delete(dev, mac_addr, ETH_ALEN, 0);
		}
	}

	dn_ifaddr_notify(RTM_DELADDR, ifa1);
	blocking_notifier_call_chain(&dnaddr_chain, NETDEV_DOWN, ifa1);
	if (destroy) {
		dn_dev_free_ifa(ifa1);

		if (dn_db->ifa_list == NULL)
			dn_dev_delete(dn_db->dev);
	}
}

static int dn_dev_insert_ifa(struct dn_dev *dn_db, struct dn_ifaddr *ifa)
{
	struct net_device *dev = dn_db->dev;
	struct dn_ifaddr *ifa1;
	unsigned char mac_addr[6];

	ASSERT_RTNL();

	/* Check for duplicates */
	for(ifa1 = dn_db->ifa_list; ifa1; ifa1 = ifa1->ifa_next) {
		if (ifa1->ifa_local == ifa->ifa_local)
			return -EEXIST;
	}

	if (dev->type == ARPHRD_ETHER) {
		if (ifa->ifa_local != dn_eth2dn(dev->dev_addr)) {
			dn_dn2eth(mac_addr, ifa->ifa_local);
			dev_mc_add(dev, mac_addr, ETH_ALEN, 0);
		}
	}

	ifa->ifa_next = dn_db->ifa_list;
	dn_db->ifa_list = ifa;

	dn_ifaddr_notify(RTM_NEWADDR, ifa);
	blocking_notifier_call_chain(&dnaddr_chain, NETDEV_UP, ifa);

	return 0;
}

static int dn_dev_set_ifa(struct net_device *dev, struct dn_ifaddr *ifa)
{
	struct dn_dev *dn_db = dev->dn_ptr;
	int rv;

	if (dn_db == NULL) {
		int err;
		dn_db = dn_dev_create(dev, &err);
		if (dn_db == NULL)
			return err;
	}

	ifa->ifa_dev = dn_db;

	if (dev->flags & IFF_LOOPBACK)
		ifa->ifa_scope = RT_SCOPE_HOST;

	rv = dn_dev_insert_ifa(dn_db, ifa);
	if (rv)
		dn_dev_free_ifa(ifa);
	return rv;
}


int dn_dev_ioctl(unsigned int cmd, void __user *arg)
{
	char buffer[DN_IFREQ_SIZE];
	struct ifreq *ifr = (struct ifreq *)buffer;
	struct sockaddr_dn *sdn = (struct sockaddr_dn *)&ifr->ifr_addr;
	struct dn_dev *dn_db;
	struct net_device *dev;
	struct dn_ifaddr *ifa = NULL, **ifap = NULL;
	int ret = 0;

	if (copy_from_user(ifr, arg, DN_IFREQ_SIZE))
		return -EFAULT;
	ifr->ifr_name[IFNAMSIZ-1] = 0;

#ifdef CONFIG_KMOD
	dev_load(&init_net, ifr->ifr_name);
#endif

	switch(cmd) {
		case SIOCGIFADDR:
			break;
		case SIOCSIFADDR:
			if (!capable(CAP_NET_ADMIN))
				return -EACCES;
			if (sdn->sdn_family != AF_DECnet)
				return -EINVAL;
			break;
		default:
			return -EINVAL;
	}

	rtnl_lock();

	if ((dev = __dev_get_by_name(&init_net, ifr->ifr_name)) == NULL) {
		ret = -ENODEV;
		goto done;
	}

	if ((dn_db = dev->dn_ptr) != NULL) {
		for (ifap = &dn_db->ifa_list; (ifa=*ifap) != NULL; ifap = &ifa->ifa_next)
			if (strcmp(ifr->ifr_name, ifa->ifa_label) == 0)
				break;
	}

	if (ifa == NULL && cmd != SIOCSIFADDR) {
		ret = -EADDRNOTAVAIL;
		goto done;
	}

	switch(cmd) {
		case SIOCGIFADDR:
			*((__le16 *)sdn->sdn_nodeaddr) = ifa->ifa_local;
			goto rarok;

		case SIOCSIFADDR:
			if (!ifa) {
				if ((ifa = dn_dev_alloc_ifa()) == NULL) {
					ret = -ENOBUFS;
					break;
				}
				memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
			} else {
				if (ifa->ifa_local == dn_saddr2dn(sdn))
					break;
				dn_dev_del_ifa(dn_db, ifap, 0);
			}

			ifa->ifa_local = ifa->ifa_address = dn_saddr2dn(sdn);

			ret = dn_dev_set_ifa(dev, ifa);
	}
done:
	rtnl_unlock();

	return ret;
rarok:
	if (copy_to_user(arg, ifr, DN_IFREQ_SIZE))
		ret = -EFAULT;
	goto done;
}

struct net_device *dn_dev_get_default(void)
{
	struct net_device *dev;
	read_lock(&dndev_lock);
	dev = decnet_default_device;
	if (dev) {
		if (dev->dn_ptr)
			dev_hold(dev);
		else
			dev = NULL;
	}
	read_unlock(&dndev_lock);
	return dev;
}

int dn_dev_set_default(struct net_device *dev, int force)
{
	struct net_device *old = NULL;
	int rv = -EBUSY;
	if (!dev->dn_ptr)
		return -ENODEV;
	write_lock(&dndev_lock);
	if (force || decnet_default_device == NULL) {
		old = decnet_default_device;
		decnet_default_device = dev;
		rv = 0;
	}
	write_unlock(&dndev_lock);
	if (old)
		dev_put(old);
	return rv;
}

static void dn_dev_check_default(struct net_device *dev)
{
	write_lock(&dndev_lock);
	if (dev == decnet_default_device) {
		decnet_default_device = NULL;
	} else {
		dev = NULL;
	}
	write_unlock(&dndev_lock);
	if (dev)
		dev_put(dev);
}

static struct dn_dev *dn_dev_by_index(int ifindex)
{
	struct net_device *dev;
	struct dn_dev *dn_dev = NULL;
	dev = dev_get_by_index(&init_net, ifindex);
	if (dev) {
		dn_dev = dev->dn_ptr;
		dev_put(dev);
	}

	return dn_dev;
}

static const struct nla_policy dn_ifa_policy[IFA_MAX+1] = {
	[IFA_ADDRESS]		= { .type = NLA_U16 },
	[IFA_LOCAL]		= { .type = NLA_U16 },
	[IFA_LABEL]		= { .type = NLA_STRING,
				    .len = IFNAMSIZ - 1 },
};

static int dn_nl_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
{
	struct nlattr *tb[IFA_MAX+1];
	struct dn_dev *dn_db;
	struct ifaddrmsg *ifm;
	struct dn_ifaddr *ifa, **ifap;
	int err = -EADDRNOTAVAIL;

	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, dn_ifa_policy);
	if (err < 0)
		goto errout;

	ifm = nlmsg_data(nlh);
	if ((dn_db = dn_dev_by_index(ifm->ifa_index)) == NULL)
		goto errout;

	for (ifap = &dn_db->ifa_list; (ifa = *ifap); ifap = &ifa->ifa_next) {
		if (tb[IFA_LOCAL] &&
		    nla_memcmp(tb[IFA_LOCAL], &ifa->ifa_local, 2))
			continue;

		if (tb[IFA_LABEL] && nla_strcmp(tb[IFA_LABEL], ifa->ifa_label))
			continue;

		dn_dev_del_ifa(dn_db, ifap, 1);
		return 0;
	}

errout:
	return err;
}

static int dn_nl_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
{
	struct nlattr *tb[IFA_MAX+1];
	struct net_device *dev;
	struct dn_dev *dn_db;
	struct ifaddrmsg *ifm;
	struct dn_ifaddr *ifa;
	int err;

	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, dn_ifa_policy);
	if (err < 0)
		return err;

	if (tb[IFA_LOCAL] == NULL)
		return -EINVAL;

	ifm = nlmsg_data(nlh);
	if ((dev = __dev_get_by_index(&init_net, ifm->ifa_index)) == NULL)
		return -ENODEV;

	if ((dn_db = dev->dn_ptr) == NULL) {
		int err;
		dn_db = dn_dev_create(dev, &err);
		if (!dn_db)
			return err;
	}

	if ((ifa = dn_dev_alloc_ifa()) == NULL)
		return -ENOBUFS;

	if (tb[IFA_ADDRESS] == NULL)
		tb[IFA_ADDRESS] = tb[IFA_LOCAL];

	ifa->ifa_local = nla_get_le16(tb[IFA_LOCAL]);
	ifa->ifa_address = nla_get_le16(tb[IFA_ADDRESS]);
	ifa->ifa_flags = ifm->ifa_flags;
	ifa->ifa_scope = ifm->ifa_scope;
	ifa->ifa_dev = dn_db;

	if (tb[IFA_LABEL])
		nla_strlcpy(ifa->ifa_label, tb[IFA_LABEL], IFNAMSIZ);
	else
		memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);

	err = dn_dev_insert_ifa(dn_db, ifa);
	if (err)
		dn_dev_free_ifa(ifa);

	return err;
}

static inline size_t dn_ifaddr_nlmsg_size(void)
{
	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
	       + nla_total_size(IFNAMSIZ) /* IFA_LABEL */
	       + nla_total_size(2) /* IFA_ADDRESS */
	       + nla_total_size(2); /* IFA_LOCAL */
}

static int dn_nl_fill_ifaddr(struct sk_buff *skb, struct dn_ifaddr *ifa,
			     u32 pid, u32 seq, int event, unsigned int flags)
{
	struct ifaddrmsg *ifm;
	struct nlmsghdr *nlh;

	nlh = nlmsg_put(skb, pid, seq, event, sizeof(*ifm), flags);
	if (nlh == NULL)
		return -EMSGSIZE;

	ifm = nlmsg_data(nlh);
	ifm->ifa_family = AF_DECnet;
	ifm->ifa_prefixlen = 16;
	ifm->ifa_flags = ifa->ifa_flags | IFA_F_PERMANENT;
	ifm->ifa_scope = ifa->ifa_scope;
	ifm->ifa_index = ifa->ifa_dev->dev->ifindex;

	if (ifa->ifa_address)
		NLA_PUT_LE16(skb, IFA_ADDRESS, ifa->ifa_address);
	if (ifa->ifa_local)
		NLA_PUT_LE16(skb, IFA_LOCAL, ifa->ifa_local);
	if (ifa->ifa_label[0])
		NLA_PUT_STRING(skb, IFA_LABEL, ifa->ifa_label);

	return nlmsg_end(skb, nlh);

nla_put_failure:
	nlmsg_cancel(skb, nlh);
	return -EMSGSIZE;
}

static void dn_ifaddr_notify(int event, struct dn_ifaddr *ifa)
{
	struct sk_buff *skb;
	int err = -ENOBUFS;

	skb = alloc_skb(dn_ifaddr_nlmsg_size(), GFP_KERNEL);
	if (skb == NULL)
		goto errout;

	err = dn_nl_fill_ifaddr(skb, ifa, 0, 0, event, 0);
	if (err < 0) {
		/* -EMSGSIZE implies BUG in dn_ifaddr_nlmsg_size() */
		WARN_ON(err == -EMSGSIZE);
		kfree_skb(skb);
		goto errout;
	}
	err = rtnl_notify(skb, 0, RTNLGRP_DECnet_IFADDR, NULL, GFP_KERNEL);
errout:
	if (err < 0)
		rtnl_set_sk_err(RTNLGRP_DECnet_IFADDR, err);
}

static int dn_nl_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
{
	int idx, dn_idx = 0, skip_ndevs, skip_naddr;
	struct net_device *dev;
	struct dn_dev *dn_db;
	struct dn_ifaddr *ifa;

	skip_ndevs = cb->args[0];
	skip_naddr = cb->args[1];

	idx = 0;
	for_each_netdev(&init_net, dev) {
		if (idx < skip_ndevs)
			goto cont;
		else if (idx > skip_ndevs) {
			/* Only skip over addresses for first dev dumped
			 * in this iteration (idx == skip_ndevs) */
			skip_naddr = 0;
		}

		if ((dn_db = dev->dn_ptr) == NULL)
			goto cont;

		for (ifa = dn_db->ifa_list, dn_idx = 0; ifa;
		     ifa = ifa->ifa_next, dn_idx++) {
			if (dn_idx < skip_naddr)
				continue;

			if (dn_nl_fill_ifaddr(skb, ifa, NETLINK_CB(cb->skb).pid,
					      cb->nlh->nlmsg_seq, RTM_NEWADDR,
					      NLM_F_MULTI) < 0)
				goto done;
		}
cont:
		idx++;
	}
done:
	cb->args[0] = idx;
	cb->args[1] = dn_idx;

	return skb->len;
}

static int dn_dev_get_first(struct net_device *dev, __le16 *addr)
{
	struct dn_dev *dn_db = (struct dn_dev *)dev->dn_ptr;
	struct dn_ifaddr *ifa;
	int rv = -ENODEV;
	if (dn_db == NULL)
		goto out;
	ifa = dn_db->ifa_list;
	if (ifa != NULL) {
		*addr = ifa->ifa_local;
		rv = 0;
	}
out:
	return rv;
}

/*
 * Find a default address to bind to.
 *
 * This is one of those areas where the initial VMS concepts don't really
 * map onto the Linux concepts, and since we introduced multiple addresses
 * per interface we have to cope with slightly odd ways of finding out what
 * "our address" really is. Mostly it's not a problem; for this we just guess
 * a sensible default. Eventually the routing code will take care of all the
 * nasties for us I hope.
 */
int dn_dev_bind_default(__le16 *addr)
{
	struct net_device *dev;
	int rv;
	dev = dn_dev_get_default();
last_chance:
	if (dev) {
		read_lock(&dev_base_lock);
		rv = dn_dev_get_first(dev, addr);
		read_unlock(&dev_base_lock);
		dev_put(dev);
		if (rv == 0 || dev == init_net.loopback_dev)
			return rv;
	}
	dev = init_net.loopback_dev;
	dev_hold(dev);
	goto last_chance;
}

static void dn_send_endnode_hello(struct net_device *dev, struct dn_ifaddr *ifa)
{
	struct endnode_hello_message *msg;
	struct sk_buff *skb = NULL;
	__le16 *pktlen;
	struct dn_dev *dn_db = (struct dn_dev *)dev->dn_ptr;

	if ((skb = dn_alloc_skb(NULL, sizeof(*msg), GFP_ATOMIC)) == NULL)
		return;

	skb->dev = dev;

	msg = (struct endnode_hello_message *)skb_put(skb,sizeof(*msg));

	msg->msgflg  = 0x0D;
	memcpy(msg->tiver, dn_eco_version, 3);
	dn_dn2eth(msg->id, ifa->ifa_local);
	msg->iinfo   = DN_RT_INFO_ENDN;
	msg->blksize = dn_htons(mtu2blksize(dev));
	msg->area    = 0x00;
	memset(msg->seed, 0, 8);
	memcpy(msg->neighbor, dn_hiord, ETH_ALEN);

	if (dn_db->router) {
		struct dn_neigh *dn = (struct dn_neigh *)dn_db->router;
		dn_dn2eth(msg->neighbor, dn->addr);
	}

	msg->timer   = dn_htons((unsigned short)dn_db->parms.t3);
	msg->mpd     = 0x00;
	msg->datalen = 0x02;
	memset(msg->data, 0xAA, 2);

	pktlen = (__le16 *)skb_push(skb,2);
	*pktlen = dn_htons(skb->len - 2);

	skb_reset_network_header(skb);

	dn_rt_finish_output(skb, dn_rt_all_rt_mcast, msg->id);
}


#define DRDELAY (5 * HZ)

static int dn_am_i_a_router(struct dn_neigh *dn, struct dn_dev *dn_db, struct dn_ifaddr *ifa)
{
	/* First check time since device went up */
	if ((jiffies - dn_db->uptime) < DRDELAY)
		return 0;

	/* If there is no router, then yes... */
	if (!dn_db->router)
		return 1;

	/* otherwise only if we have a higher priority or.. */
	if (dn->priority < dn_db->parms.priority)
		return 1;

	/* if we have equal priority and a higher node number */
	if (dn->priority != dn_db->parms.priority)
		return 0;

	if (dn_ntohs(dn->addr) < dn_ntohs(ifa->ifa_local))
		return 1;

	return 0;
}

static void dn_send_router_hello(struct net_device *dev, struct dn_ifaddr *ifa)
{
	int n;
	struct dn_dev *dn_db = dev->dn_ptr;
	struct dn_neigh *dn = (struct dn_neigh *)dn_db->router;
	struct sk_buff *skb;
	size_t size;
	unsigned char *ptr;
	unsigned char *i1, *i2;
	__le16 *pktlen;
	char *src;

	if (mtu2blksize(dev) < (26 + 7))
		return;

	n = mtu2blksize(dev) - 26;
	n /= 7;

	if (n > 32)
		n = 32;

	size = 2 + 26 + 7 * n;

	if ((skb = dn_alloc_skb(NULL, size, GFP_ATOMIC)) == NULL)
		return;

	skb->dev = dev;
	ptr = skb_put(skb, size);

	*ptr++ = DN_RT_PKT_CNTL | DN_RT_PKT_ERTH;
	*ptr++ = 2; /* ECO */
	*ptr++ = 0;
	*ptr++ = 0;
	dn_dn2eth(ptr, ifa->ifa_local);
	src = ptr;
	ptr += ETH_ALEN;
	*ptr++ = dn_db->parms.forwarding == 1 ?
			DN_RT_INFO_L1RT : DN_RT_INFO_L2RT;
	*((__le16 *)ptr) = dn_htons(mtu2blksize(dev));
	ptr += 2;
	*ptr++ = dn_db->parms.priority; /* Priority */
	*ptr++ = 0; /* Area: Reserved */
	*((__le16 *)ptr) = dn_htons((unsigned short)dn_db->parms.t3);
	ptr += 2;
	*ptr++ = 0; /* MPD: Reserved */
	i1 = ptr++;
	memset(ptr, 0, 7); /* Name: Reserved */
	ptr += 7;
	i2 = ptr++;

	n = dn_neigh_elist(dev, ptr, n);

	*i2 = 7 * n;
	*i1 = 8 + *i2;

	skb_trim(skb, (27 + *i2));

	pktlen = (__le16 *)skb_push(skb, 2);
	*pktlen = dn_htons(skb->len - 2);

	skb_reset_network_header(skb);

	if (dn_am_i_a_router(dn, dn_db, ifa)) {
		struct sk_buff *skb2 = skb_copy(skb, GFP_ATOMIC);
		if (skb2) {
			dn_rt_finish_output(skb2, dn_rt_all_end_mcast, src);
		}
	}

	dn_rt_finish_output(skb, dn_rt_all_rt_mcast, src);
}

static void dn_send_brd_hello(struct net_device *dev, struct dn_ifaddr *ifa)
{
	struct dn_dev *dn_db = (struct dn_dev *)dev->dn_ptr;

	if (dn_db->parms.forwarding == 0)
		dn_send_endnode_hello(dev, ifa);
	else
		dn_send_router_hello(dev, ifa);
}

static void dn_send_ptp_hello(struct net_device *dev, struct dn_ifaddr *ifa)
{
	int tdlen = 16;
	int size = dev->hard_header_len + 2 + 4 + tdlen;
	struct sk_buff *skb = dn_alloc_skb(NULL, size, GFP_ATOMIC);
	int i;
	unsigned char *ptr;
	char src[ETH_ALEN];

	if (skb == NULL)
		return ;

	skb->dev = dev;
	skb_push(skb, dev->hard_header_len);
	ptr = skb_put(skb, 2 + 4 + tdlen);

	*ptr++ = DN_RT_PKT_HELO;
	*((__le16 *)ptr) = ifa->ifa_local;
	ptr += 2;
	*ptr++ = tdlen;

	for(i = 0; i < tdlen; i++)
		*ptr++ = 0252;

	dn_dn2eth(src, ifa->ifa_local);
	dn_rt_finish_output(skb, dn_rt_all_rt_mcast, src);
}

static int dn_eth_up(struct net_device *dev)
{
	struct dn_dev *dn_db = dev->dn_ptr;

	if (dn_db->parms.forwarding == 0)
		dev_mc_add(dev, dn_rt_all_end_mcast, ETH_ALEN, 0);
	else
		dev_mc_add(dev, dn_rt_all_rt_mcast, ETH_ALEN, 0);

	dn_db->use_long = 1;

	return 0;
}

static void dn_eth_down(struct net_device *dev)
{
	struct dn_dev *dn_db = dev->dn_ptr;

	if (dn_db->parms.forwarding == 0)
		dev_mc_delete(dev, dn_rt_all_end_mcast, ETH_ALEN, 0);
	else
		dev_mc_delete(dev, dn_rt_all_rt_mcast, ETH_ALEN, 0);
}

static void dn_dev_set_timer(struct net_device *dev);

static void dn_dev_timer_func(unsigned long arg)
{
	struct net_device *dev = (struct net_device *)arg;
	struct dn_dev *dn_db = dev->dn_ptr;
	struct dn_ifaddr *ifa;

	if (dn_db->t3 <= dn_db->parms.t2) {
		if (dn_db->parms.timer3) {
			for(ifa = dn_db->ifa_list; ifa; ifa = ifa->ifa_next) {
				if (!(ifa->ifa_flags & IFA_F_SECONDARY))
					dn_db->parms.timer3(dev, ifa);
			}
		}
		dn_db->t3 = dn_db->parms.t3;
	} else {
		dn_db->t3 -= dn_db->parms.t2;
	}

	dn_dev_set_timer(dev);
}

static void dn_dev_set_timer(struct net_device *dev)
{
	struct dn_dev *dn_db = dev->dn_ptr;

	if (dn_db->parms.t2 > dn_db->parms.t3)
		dn_db->parms.t2 = dn_db->parms.t3;

	dn_db->timer.data = (unsigned long)dev;
	dn_db->timer.function = dn_dev_timer_func;
	dn_db->timer.expires = jiffies + (dn_db->parms.t2 * HZ);

	add_timer(&dn_db->timer);
}

struct dn_dev *dn_dev_create(struct net_device *dev, int *err)
{
	int i;
	struct dn_dev_parms *p = dn_dev_list;
	struct dn_dev *dn_db;

	for(i = 0; i < DN_DEV_LIST_SIZE; i++, p++) {
		if (p->type == dev->type)
			break;
	}

	*err = -ENODEV;
	if (i == DN_DEV_LIST_SIZE)
		return NULL;

	*err = -ENOBUFS;
	if ((dn_db = kzalloc(sizeof(struct dn_dev), GFP_ATOMIC)) == NULL)
		return NULL;

	memcpy(&dn_db->parms, p, sizeof(struct dn_dev_parms));
	smp_wmb();
	dev->dn_ptr = dn_db;
	dn_db->dev = dev;
	init_timer(&dn_db->timer);

	dn_db->uptime = jiffies;

	dn_db->neigh_parms = neigh_parms_alloc(dev, &dn_neigh_table);
	if (!dn_db->neigh_parms) {
		dev->dn_ptr = NULL;
		kfree(dn_db);
		return NULL;
	}

	if (dn_db->parms.up) {
		if (dn_db->parms.up(dev) < 0) {
			neigh_parms_release(&dn_neigh_table, dn_db->neigh_parms);
			dev->dn_ptr = NULL;
			kfree(dn_db);
			return NULL;
		}
	}

	dn_dev_sysctl_register(dev, &dn_db->parms);

	dn_dev_set_timer(dev);

	*err = 0;
	return dn_db;
}


/*
 * This processes a device up event. We only start up
 * the loopback device & ethernet devices with correct
 * MAC addreses automatically. Others must be started
 * specifically.
 *
 * FIXME: How should we configure the loopback address ? If we could dispense
 * with using decnet_address here and for autobind, it will be one less thing
 * for users to worry about setting up.
 */

void dn_dev_up(struct net_device *dev)
{
	struct dn_ifaddr *ifa;
	__le16 addr = decnet_address;
	int maybe_default = 0;
	struct dn_dev *dn_db = (struct dn_dev *)dev->dn_ptr;

	if ((dev->type != ARPHRD_ETHER) && (dev->type != ARPHRD_LOOPBACK))
		return;

	/*
	 * Need to ensure that loopback device has a dn_db attached to it
	 * to allow creation of neighbours against it, even though it might
	 * not have a local address of its own. Might as well do the same for
	 * all autoconfigured interfaces.
	 */
	if (dn_db == NULL) {
		int err;
		dn_db = dn_dev_create(dev, &err);
		if (dn_db == NULL)
			return;
	}

	if (dev->type == ARPHRD_ETHER) {
		if (memcmp(dev->dev_addr, dn_hiord, 4) != 0)
			return;
		addr = dn_eth2dn(dev->dev_addr);
		maybe_default = 1;
	}

	if (addr == 0)
		return;

	if ((ifa = dn_dev_alloc_ifa()) == NULL)
		return;

	ifa->ifa_local = ifa->ifa_address = addr;
	ifa->ifa_flags = 0;
	ifa->ifa_scope = RT_SCOPE_UNIVERSE;
	strcpy(ifa->ifa_label, dev->name);

	dn_dev_set_ifa(dev, ifa);

	/*
	 * Automagically set the default device to the first automatically
	 * configured ethernet card in the system.
	 */
	if (maybe_default) {
		dev_hold(dev);
		if (dn_dev_set_default(dev, 0))
			dev_put(dev);
	}
}

static void dn_dev_delete(struct net_device *dev)
{
	struct dn_dev *dn_db = dev->dn_ptr;

	if (dn_db == NULL)
		return;

	del_timer_sync(&dn_db->timer);
	dn_dev_sysctl_unregister(&dn_db->parms);
	dn_dev_check_default(dev);
	neigh_ifdown(&dn_neigh_table, dev);

	if (dn_db->parms.down)
		dn_db->parms.down(dev);

	dev->dn_ptr = NULL;

	neigh_parms_release(&dn_neigh_table, dn_db->neigh_parms);
	neigh_ifdown(&dn_neigh_table, dev);

	if (dn_db->router)
		neigh_release(dn_db->router);
	if (dn_db->peer)
		neigh_release(dn_db->peer);

	kfree(dn_db);
}

void dn_dev_down(struct net_device *dev)
{
	struct dn_dev *dn_db = dev->dn_ptr;
	struct dn_ifaddr *ifa;

	if (dn_db == NULL)
		return;

	while((ifa = dn_db->ifa_list) != NULL) {
		dn_dev_del_ifa(dn_db, &dn_db->ifa_list, 0);
		dn_dev_free_ifa(ifa);
	}

	dn_dev_delete(dev);
}

void dn_dev_init_pkt(struct sk_buff *skb)
{
	return;
}

void dn_dev_veri_pkt(struct sk_buff *skb)
{
	return;
}

void dn_dev_hello(struct sk_buff *skb)
{
	return;
}

void dn_dev_devices_off(void)
{
	struct net_device *dev;

	rtnl_lock();
	for_each_netdev(&init_net, dev)
		dn_dev_down(dev);
	rtnl_unlock();

}

void dn_dev_devices_on(void)
{
	struct net_device *dev;

	rtnl_lock();
	for_each_netdev(&init_net, dev) {
		if (dev->flags & IFF_UP)
			dn_dev_up(dev);
	}
	rtnl_unlock();
}

int register_dnaddr_notifier(struct notifier_block *nb)
{
	return blocking_notifier_chain_register(&dnaddr_chain, nb);
}

int unregister_dnaddr_notifier(struct notifier_block *nb)
{
	return blocking_notifier_chain_unregister(&dnaddr_chain, nb);
}

#ifdef CONFIG_PROC_FS
static inline int is_dn_dev(struct net_device *dev)
{
	return dev->dn_ptr != NULL;
}

static void *dn_dev_seq_start(struct seq_file *seq, loff_t *pos)
{
	int i;
	struct net_device *dev;

	read_lock(&dev_base_lock);

	if (*pos == 0)
		return SEQ_START_TOKEN;

	i = 1;
	for_each_netdev(&init_net, dev) {
		if (!is_dn_dev(dev))
			continue;

		if (i++ == *pos)
			return dev;
	}

	return NULL;
}

static void *dn_dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
	struct net_device *dev;

	++*pos;

	dev = (struct net_device *)v;
	if (v == SEQ_START_TOKEN)
		dev = net_device_entry(&init_net.dev_base_head);

	for_each_netdev_continue(&init_net, dev) {
		if (!is_dn_dev(dev))
			continue;

		return dev;
	}

	return NULL;
}

static void dn_dev_seq_stop(struct seq_file *seq, void *v)
{
	read_unlock(&dev_base_lock);
}

static char *dn_type2asc(char type)
{
	switch(type) {
		case DN_DEV_BCAST:
			return "B";
		case DN_DEV_UCAST:
			return "U";
		case DN_DEV_MPOINT:
			return "M";
	}

	return "?";
}

static int dn_dev_seq_show(struct seq_file *seq, void *v)
{
	if (v == SEQ_START_TOKEN)
		seq_puts(seq, "Name     Flags T1   Timer1 T3   Timer3 BlkSize Pri State DevType    Router Peer\n");
	else {
		struct net_device *dev = v;
		char peer_buf[DN_ASCBUF_LEN];
		char router_buf[DN_ASCBUF_LEN];
		struct dn_dev *dn_db = dev->dn_ptr;

		seq_printf(seq, "%-8s %1s     %04u %04u   %04lu %04lu"
				"   %04hu    %03d %02x    %-10s %-7s %-7s\n",
				dev->name ? dev->name : "???",
				dn_type2asc(dn_db->parms.mode),
				0, 0,
				dn_db->t3, dn_db->parms.t3,
				mtu2blksize(dev),
				dn_db->parms.priority,
				dn_db->parms.state, dn_db->parms.name,
				dn_db->router ? dn_addr2asc(dn_ntohs(*(__le16 *)dn_db->router->primary_key), router_buf) : "",
				dn_db->peer ? dn_addr2asc(dn_ntohs(*(__le16 *)dn_db->peer->primary_key), peer_buf) : "");
	}
	return 0;
}

static const struct seq_operations dn_dev_seq_ops = {
	.start	= dn_dev_seq_start,
	.next	= dn_dev_seq_next,
	.stop	= dn_dev_seq_stop,
	.show	= dn_dev_seq_show,
};

static int dn_dev_seq_open(struct inode *inode, struct file *file)
{
	return seq_open(file, &dn_dev_seq_ops);
}

static const struct file_operations dn_dev_seq_fops = {
	.owner	 = THIS_MODULE,
	.open	 = dn_dev_seq_open,
	.read	 = seq_read,
	.llseek	 = seq_lseek,
	.release = seq_release,
};

#endif /* CONFIG_PROC_FS */

static int addr[2];
module_param_array(addr, int, NULL, 0444);
MODULE_PARM_DESC(addr, "The DECnet address of this machine: area,node");

void __init dn_dev_init(void)
{
	if (addr[0] > 63 || addr[0] < 0) {
		printk(KERN_ERR "DECnet: Area must be between 0 and 63");
		return;
	}

	if (addr[1] > 1023 || addr[1] < 0) {
		printk(KERN_ERR "DECnet: Node must be between 0 and 1023");
		return;
	}

	decnet_address = dn_htons((addr[0] << 10) | addr[1]);

	dn_dev_devices_on();

	rtnl_register(PF_DECnet, RTM_NEWADDR, dn_nl_newaddr, NULL);
	rtnl_register(PF_DECnet, RTM_DELADDR, dn_nl_deladdr, NULL);
	rtnl_register(PF_DECnet, RTM_GETADDR, NULL, dn_nl_dump_ifaddr);

	proc_net_fops_create(&init_net, "decnet_dev", S_IRUGO, &dn_dev_seq_fops);

#ifdef CONFIG_SYSCTL
	{
		int i;
		for(i = 0; i < DN_DEV_LIST_SIZE; i++)
			dn_dev_sysctl_register(NULL, &dn_dev_list[i]);
	}
#endif /* CONFIG_SYSCTL */
}

void __exit dn_dev_cleanup(void)
{
#ifdef CONFIG_SYSCTL
	{
		int i;
		for(i = 0; i < DN_DEV_LIST_SIZE; i++)
			dn_dev_sysctl_unregister(&dn_dev_list[i]);
	}
#endif /* CONFIG_SYSCTL */

	proc_net_remove(&init_net, "decnet_dev");

	dn_dev_devices_off();
}