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1/*
2 * This program is free software; you can redistribute it and/or modify
3 * it under the terms of the GNU General Public License as published by
4 * the Free Software Foundation; either version 2 of the License, or
5 * (at your option) any later version.
6 *
7 * Copyright Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
8 * Copyright Alan Cox GW4PTS (alan@lxorguk.ukuu.org.uk)
9 * Copyright Tomi Manninen OH2BNS (oh2bns@sral.fi)
10 */
11#include <linux/errno.h>
12#include <linux/types.h>
13#include <linux/socket.h>
14#include <linux/in.h>
15#include <linux/kernel.h>
16#include <linux/timer.h>
17#include <linux/string.h>
18#include <linux/sockios.h>
19#include <linux/net.h>
20#include <linux/slab.h>
21#include <net/ax25.h>
22#include <linux/inet.h>
23#include <linux/netdevice.h>
24#include <net/arp.h>
25#include <linux/if_arp.h>
26#include <linux/skbuff.h>
27#include <net/sock.h>
28#include <linux/uaccess.h>
29#include <linux/fcntl.h>
30#include <linux/termios.h> /* For TIOCINQ/OUTQ */
31#include <linux/mm.h>
32#include <linux/interrupt.h>
33#include <linux/notifier.h>
34#include <linux/init.h>
35#include <linux/spinlock.h>
36#include <net/netrom.h>
37#include <linux/seq_file.h>
38#include <linux/export.h>
39
40static unsigned int nr_neigh_no = 1;
41
42static HLIST_HEAD(nr_node_list);
43static DEFINE_SPINLOCK(nr_node_list_lock);
44static HLIST_HEAD(nr_neigh_list);
45static DEFINE_SPINLOCK(nr_neigh_list_lock);
46
47static struct nr_node *nr_node_get(ax25_address *callsign)
48{
49 struct nr_node *found = NULL;
50 struct nr_node *nr_node;
51
52 spin_lock_bh(&nr_node_list_lock);
53 nr_node_for_each(nr_node, &nr_node_list)
54 if (ax25cmp(callsign, &nr_node->callsign) == 0) {
55 nr_node_hold(nr_node);
56 found = nr_node;
57 break;
58 }
59 spin_unlock_bh(&nr_node_list_lock);
60 return found;
61}
62
63static struct nr_neigh *nr_neigh_get_dev(ax25_address *callsign,
64 struct net_device *dev)
65{
66 struct nr_neigh *found = NULL;
67 struct nr_neigh *nr_neigh;
68
69 spin_lock_bh(&nr_neigh_list_lock);
70 nr_neigh_for_each(nr_neigh, &nr_neigh_list)
71 if (ax25cmp(callsign, &nr_neigh->callsign) == 0 &&
72 nr_neigh->dev == dev) {
73 nr_neigh_hold(nr_neigh);
74 found = nr_neigh;
75 break;
76 }
77 spin_unlock_bh(&nr_neigh_list_lock);
78 return found;
79}
80
81static void nr_remove_neigh(struct nr_neigh *);
82
83/*
84 * Add a new route to a node, and in the process add the node and the
85 * neighbour if it is new.
86 */
87static int __must_check nr_add_node(ax25_address *nr, const char *mnemonic,
88 ax25_address *ax25, ax25_digi *ax25_digi, struct net_device *dev,
89 int quality, int obs_count)
90{
91 struct nr_node *nr_node;
92 struct nr_neigh *nr_neigh;
93 struct nr_route nr_route;
94 int i, found;
95 struct net_device *odev;
96
97 if ((odev=nr_dev_get(nr)) != NULL) { /* Can't add routes to ourself */
98 dev_put(odev);
99 return -EINVAL;
100 }
101
102 nr_node = nr_node_get(nr);
103
104 nr_neigh = nr_neigh_get_dev(ax25, dev);
105
106 /*
107 * The L2 link to a neighbour has failed in the past
108 * and now a frame comes from this neighbour. We assume
109 * it was a temporary trouble with the link and reset the
110 * routes now (and not wait for a node broadcast).
111 */
112 if (nr_neigh != NULL && nr_neigh->failed != 0 && quality == 0) {
113 struct nr_node *nr_nodet;
114
115 spin_lock_bh(&nr_node_list_lock);
116 nr_node_for_each(nr_nodet, &nr_node_list) {
117 nr_node_lock(nr_nodet);
118 for (i = 0; i < nr_nodet->count; i++)
119 if (nr_nodet->routes[i].neighbour == nr_neigh)
120 if (i < nr_nodet->which)
121 nr_nodet->which = i;
122 nr_node_unlock(nr_nodet);
123 }
124 spin_unlock_bh(&nr_node_list_lock);
125 }
126
127 if (nr_neigh != NULL)
128 nr_neigh->failed = 0;
129
130 if (quality == 0 && nr_neigh != NULL && nr_node != NULL) {
131 nr_neigh_put(nr_neigh);
132 nr_node_put(nr_node);
133 return 0;
134 }
135
136 if (nr_neigh == NULL) {
137 if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL) {
138 if (nr_node)
139 nr_node_put(nr_node);
140 return -ENOMEM;
141 }
142
143 nr_neigh->callsign = *ax25;
144 nr_neigh->digipeat = NULL;
145 nr_neigh->ax25 = NULL;
146 nr_neigh->dev = dev;
147 nr_neigh->quality = sysctl_netrom_default_path_quality;
148 nr_neigh->locked = 0;
149 nr_neigh->count = 0;
150 nr_neigh->number = nr_neigh_no++;
151 nr_neigh->failed = 0;
152 atomic_set(&nr_neigh->refcount, 1);
153
154 if (ax25_digi != NULL && ax25_digi->ndigi > 0) {
155 nr_neigh->digipeat = kmemdup(ax25_digi,
156 sizeof(*ax25_digi),
157 GFP_KERNEL);
158 if (nr_neigh->digipeat == NULL) {
159 kfree(nr_neigh);
160 if (nr_node)
161 nr_node_put(nr_node);
162 return -ENOMEM;
163 }
164 }
165
166 spin_lock_bh(&nr_neigh_list_lock);
167 hlist_add_head(&nr_neigh->neigh_node, &nr_neigh_list);
168 nr_neigh_hold(nr_neigh);
169 spin_unlock_bh(&nr_neigh_list_lock);
170 }
171
172 if (quality != 0 && ax25cmp(nr, ax25) == 0 && !nr_neigh->locked)
173 nr_neigh->quality = quality;
174
175 if (nr_node == NULL) {
176 if ((nr_node = kmalloc(sizeof(*nr_node), GFP_ATOMIC)) == NULL) {
177 if (nr_neigh)
178 nr_neigh_put(nr_neigh);
179 return -ENOMEM;
180 }
181
182 nr_node->callsign = *nr;
183 strcpy(nr_node->mnemonic, mnemonic);
184
185 nr_node->which = 0;
186 nr_node->count = 1;
187 atomic_set(&nr_node->refcount, 1);
188 spin_lock_init(&nr_node->node_lock);
189
190 nr_node->routes[0].quality = quality;
191 nr_node->routes[0].obs_count = obs_count;
192 nr_node->routes[0].neighbour = nr_neigh;
193
194 nr_neigh_hold(nr_neigh);
195 nr_neigh->count++;
196
197 spin_lock_bh(&nr_node_list_lock);
198 hlist_add_head(&nr_node->node_node, &nr_node_list);
199 /* refcount initialized at 1 */
200 spin_unlock_bh(&nr_node_list_lock);
201
202 return 0;
203 }
204 nr_node_lock(nr_node);
205
206 if (quality != 0)
207 strcpy(nr_node->mnemonic, mnemonic);
208
209 for (found = 0, i = 0; i < nr_node->count; i++) {
210 if (nr_node->routes[i].neighbour == nr_neigh) {
211 nr_node->routes[i].quality = quality;
212 nr_node->routes[i].obs_count = obs_count;
213 found = 1;
214 break;
215 }
216 }
217
218 if (!found) {
219 /* We have space at the bottom, slot it in */
220 if (nr_node->count < 3) {
221 nr_node->routes[2] = nr_node->routes[1];
222 nr_node->routes[1] = nr_node->routes[0];
223
224 nr_node->routes[0].quality = quality;
225 nr_node->routes[0].obs_count = obs_count;
226 nr_node->routes[0].neighbour = nr_neigh;
227
228 nr_node->which++;
229 nr_node->count++;
230 nr_neigh_hold(nr_neigh);
231 nr_neigh->count++;
232 } else {
233 /* It must be better than the worst */
234 if (quality > nr_node->routes[2].quality) {
235 nr_node->routes[2].neighbour->count--;
236 nr_neigh_put(nr_node->routes[2].neighbour);
237
238 if (nr_node->routes[2].neighbour->count == 0 && !nr_node->routes[2].neighbour->locked)
239 nr_remove_neigh(nr_node->routes[2].neighbour);
240
241 nr_node->routes[2].quality = quality;
242 nr_node->routes[2].obs_count = obs_count;
243 nr_node->routes[2].neighbour = nr_neigh;
244
245 nr_neigh_hold(nr_neigh);
246 nr_neigh->count++;
247 }
248 }
249 }
250
251 /* Now re-sort the routes in quality order */
252 switch (nr_node->count) {
253 case 3:
254 if (nr_node->routes[1].quality > nr_node->routes[0].quality) {
255 switch (nr_node->which) {
256 case 0:
257 nr_node->which = 1;
258 break;
259 case 1:
260 nr_node->which = 0;
261 break;
262 }
263 nr_route = nr_node->routes[0];
264 nr_node->routes[0] = nr_node->routes[1];
265 nr_node->routes[1] = nr_route;
266 }
267 if (nr_node->routes[2].quality > nr_node->routes[1].quality) {
268 switch (nr_node->which) {
269 case 1: nr_node->which = 2;
270 break;
271
272 case 2: nr_node->which = 1;
273 break;
274
275 default:
276 break;
277 }
278 nr_route = nr_node->routes[1];
279 nr_node->routes[1] = nr_node->routes[2];
280 nr_node->routes[2] = nr_route;
281 }
282 case 2:
283 if (nr_node->routes[1].quality > nr_node->routes[0].quality) {
284 switch (nr_node->which) {
285 case 0: nr_node->which = 1;
286 break;
287
288 case 1: nr_node->which = 0;
289 break;
290
291 default: break;
292 }
293 nr_route = nr_node->routes[0];
294 nr_node->routes[0] = nr_node->routes[1];
295 nr_node->routes[1] = nr_route;
296 }
297 case 1:
298 break;
299 }
300
301 for (i = 0; i < nr_node->count; i++) {
302 if (nr_node->routes[i].neighbour == nr_neigh) {
303 if (i < nr_node->which)
304 nr_node->which = i;
305 break;
306 }
307 }
308
309 nr_neigh_put(nr_neigh);
310 nr_node_unlock(nr_node);
311 nr_node_put(nr_node);
312 return 0;
313}
314
315static inline void __nr_remove_node(struct nr_node *nr_node)
316{
317 hlist_del_init(&nr_node->node_node);
318 nr_node_put(nr_node);
319}
320
321#define nr_remove_node_locked(__node) \
322 __nr_remove_node(__node)
323
324static void nr_remove_node(struct nr_node *nr_node)
325{
326 spin_lock_bh(&nr_node_list_lock);
327 __nr_remove_node(nr_node);
328 spin_unlock_bh(&nr_node_list_lock);
329}
330
331static inline void __nr_remove_neigh(struct nr_neigh *nr_neigh)
332{
333 hlist_del_init(&nr_neigh->neigh_node);
334 nr_neigh_put(nr_neigh);
335}
336
337#define nr_remove_neigh_locked(__neigh) \
338 __nr_remove_neigh(__neigh)
339
340static void nr_remove_neigh(struct nr_neigh *nr_neigh)
341{
342 spin_lock_bh(&nr_neigh_list_lock);
343 __nr_remove_neigh(nr_neigh);
344 spin_unlock_bh(&nr_neigh_list_lock);
345}
346
347/*
348 * "Delete" a node. Strictly speaking remove a route to a node. The node
349 * is only deleted if no routes are left to it.
350 */
351static int nr_del_node(ax25_address *callsign, ax25_address *neighbour, struct net_device *dev)
352{
353 struct nr_node *nr_node;
354 struct nr_neigh *nr_neigh;
355 int i;
356
357 nr_node = nr_node_get(callsign);
358
359 if (nr_node == NULL)
360 return -EINVAL;
361
362 nr_neigh = nr_neigh_get_dev(neighbour, dev);
363
364 if (nr_neigh == NULL) {
365 nr_node_put(nr_node);
366 return -EINVAL;
367 }
368
369 nr_node_lock(nr_node);
370 for (i = 0; i < nr_node->count; i++) {
371 if (nr_node->routes[i].neighbour == nr_neigh) {
372 nr_neigh->count--;
373 nr_neigh_put(nr_neigh);
374
375 if (nr_neigh->count == 0 && !nr_neigh->locked)
376 nr_remove_neigh(nr_neigh);
377 nr_neigh_put(nr_neigh);
378
379 nr_node->count--;
380
381 if (nr_node->count == 0) {
382 nr_remove_node(nr_node);
383 } else {
384 switch (i) {
385 case 0:
386 nr_node->routes[0] = nr_node->routes[1];
387 case 1:
388 nr_node->routes[1] = nr_node->routes[2];
389 case 2:
390 break;
391 }
392 nr_node_put(nr_node);
393 }
394 nr_node_unlock(nr_node);
395
396 return 0;
397 }
398 }
399 nr_neigh_put(nr_neigh);
400 nr_node_unlock(nr_node);
401 nr_node_put(nr_node);
402
403 return -EINVAL;
404}
405
406/*
407 * Lock a neighbour with a quality.
408 */
409static int __must_check nr_add_neigh(ax25_address *callsign,
410 ax25_digi *ax25_digi, struct net_device *dev, unsigned int quality)
411{
412 struct nr_neigh *nr_neigh;
413
414 nr_neigh = nr_neigh_get_dev(callsign, dev);
415 if (nr_neigh) {
416 nr_neigh->quality = quality;
417 nr_neigh->locked = 1;
418 nr_neigh_put(nr_neigh);
419 return 0;
420 }
421
422 if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL)
423 return -ENOMEM;
424
425 nr_neigh->callsign = *callsign;
426 nr_neigh->digipeat = NULL;
427 nr_neigh->ax25 = NULL;
428 nr_neigh->dev = dev;
429 nr_neigh->quality = quality;
430 nr_neigh->locked = 1;
431 nr_neigh->count = 0;
432 nr_neigh->number = nr_neigh_no++;
433 nr_neigh->failed = 0;
434 atomic_set(&nr_neigh->refcount, 1);
435
436 if (ax25_digi != NULL && ax25_digi->ndigi > 0) {
437 nr_neigh->digipeat = kmemdup(ax25_digi, sizeof(*ax25_digi),
438 GFP_KERNEL);
439 if (nr_neigh->digipeat == NULL) {
440 kfree(nr_neigh);
441 return -ENOMEM;
442 }
443 }
444
445 spin_lock_bh(&nr_neigh_list_lock);
446 hlist_add_head(&nr_neigh->neigh_node, &nr_neigh_list);
447 /* refcount is initialized at 1 */
448 spin_unlock_bh(&nr_neigh_list_lock);
449
450 return 0;
451}
452
453/*
454 * "Delete" a neighbour. The neighbour is only removed if the number
455 * of nodes that may use it is zero.
456 */
457static int nr_del_neigh(ax25_address *callsign, struct net_device *dev, unsigned int quality)
458{
459 struct nr_neigh *nr_neigh;
460
461 nr_neigh = nr_neigh_get_dev(callsign, dev);
462
463 if (nr_neigh == NULL) return -EINVAL;
464
465 nr_neigh->quality = quality;
466 nr_neigh->locked = 0;
467
468 if (nr_neigh->count == 0)
469 nr_remove_neigh(nr_neigh);
470 nr_neigh_put(nr_neigh);
471
472 return 0;
473}
474
475/*
476 * Decrement the obsolescence count by one. If a route is reduced to a
477 * count of zero, remove it. Also remove any unlocked neighbours with
478 * zero nodes routing via it.
479 */
480static int nr_dec_obs(void)
481{
482 struct nr_neigh *nr_neigh;
483 struct nr_node *s;
484 struct hlist_node *nodet;
485 int i;
486
487 spin_lock_bh(&nr_node_list_lock);
488 nr_node_for_each_safe(s, nodet, &nr_node_list) {
489 nr_node_lock(s);
490 for (i = 0; i < s->count; i++) {
491 switch (s->routes[i].obs_count) {
492 case 0: /* A locked entry */
493 break;
494
495 case 1: /* From 1 -> 0 */
496 nr_neigh = s->routes[i].neighbour;
497
498 nr_neigh->count--;
499 nr_neigh_put(nr_neigh);
500
501 if (nr_neigh->count == 0 && !nr_neigh->locked)
502 nr_remove_neigh(nr_neigh);
503
504 s->count--;
505
506 switch (i) {
507 case 0:
508 s->routes[0] = s->routes[1];
509 /* Fallthrough */
510 case 1:
511 s->routes[1] = s->routes[2];
512 case 2:
513 break;
514 }
515 break;
516
517 default:
518 s->routes[i].obs_count--;
519 break;
520
521 }
522 }
523
524 if (s->count <= 0)
525 nr_remove_node_locked(s);
526 nr_node_unlock(s);
527 }
528 spin_unlock_bh(&nr_node_list_lock);
529
530 return 0;
531}
532
533/*
534 * A device has been removed. Remove its routes and neighbours.
535 */
536void nr_rt_device_down(struct net_device *dev)
537{
538 struct nr_neigh *s;
539 struct hlist_node *nodet, *node2t;
540 struct nr_node *t;
541 int i;
542
543 spin_lock_bh(&nr_neigh_list_lock);
544 nr_neigh_for_each_safe(s, nodet, &nr_neigh_list) {
545 if (s->dev == dev) {
546 spin_lock_bh(&nr_node_list_lock);
547 nr_node_for_each_safe(t, node2t, &nr_node_list) {
548 nr_node_lock(t);
549 for (i = 0; i < t->count; i++) {
550 if (t->routes[i].neighbour == s) {
551 t->count--;
552
553 switch (i) {
554 case 0:
555 t->routes[0] = t->routes[1];
556 case 1:
557 t->routes[1] = t->routes[2];
558 case 2:
559 break;
560 }
561 }
562 }
563
564 if (t->count <= 0)
565 nr_remove_node_locked(t);
566 nr_node_unlock(t);
567 }
568 spin_unlock_bh(&nr_node_list_lock);
569
570 nr_remove_neigh_locked(s);
571 }
572 }
573 spin_unlock_bh(&nr_neigh_list_lock);
574}
575
576/*
577 * Check that the device given is a valid AX.25 interface that is "up".
578 * Or a valid ethernet interface with an AX.25 callsign binding.
579 */
580static struct net_device *nr_ax25_dev_get(char *devname)
581{
582 struct net_device *dev;
583
584 if ((dev = dev_get_by_name(&init_net, devname)) == NULL)
585 return NULL;
586
587 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_AX25)
588 return dev;
589
590 dev_put(dev);
591 return NULL;
592}
593
594/*
595 * Find the first active NET/ROM device, usually "nr0".
596 */
597struct net_device *nr_dev_first(void)
598{
599 struct net_device *dev, *first = NULL;
600
601 rcu_read_lock();
602 for_each_netdev_rcu(&init_net, dev) {
603 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM)
604 if (first == NULL || strncmp(dev->name, first->name, 3) < 0)
605 first = dev;
606 }
607 if (first)
608 dev_hold(first);
609 rcu_read_unlock();
610
611 return first;
612}
613
614/*
615 * Find the NET/ROM device for the given callsign.
616 */
617struct net_device *nr_dev_get(ax25_address *addr)
618{
619 struct net_device *dev;
620
621 rcu_read_lock();
622 for_each_netdev_rcu(&init_net, dev) {
623 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM &&
624 ax25cmp(addr, (ax25_address *)dev->dev_addr) == 0) {
625 dev_hold(dev);
626 goto out;
627 }
628 }
629 dev = NULL;
630out:
631 rcu_read_unlock();
632 return dev;
633}
634
635static ax25_digi *nr_call_to_digi(ax25_digi *digi, int ndigis,
636 ax25_address *digipeaters)
637{
638 int i;
639
640 if (ndigis == 0)
641 return NULL;
642
643 for (i = 0; i < ndigis; i++) {
644 digi->calls[i] = digipeaters[i];
645 digi->repeated[i] = 0;
646 }
647
648 digi->ndigi = ndigis;
649 digi->lastrepeat = -1;
650
651 return digi;
652}
653
654/*
655 * Handle the ioctls that control the routing functions.
656 */
657int nr_rt_ioctl(unsigned int cmd, void __user *arg)
658{
659 struct nr_route_struct nr_route;
660 struct net_device *dev;
661 ax25_digi digi;
662 int ret;
663
664 switch (cmd) {
665 case SIOCADDRT:
666 if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct)))
667 return -EFAULT;
668 if (nr_route.ndigis > AX25_MAX_DIGIS)
669 return -EINVAL;
670 if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL)
671 return -EINVAL;
672 switch (nr_route.type) {
673 case NETROM_NODE:
674 if (strnlen(nr_route.mnemonic, 7) == 7) {
675 ret = -EINVAL;
676 break;
677 }
678
679 ret = nr_add_node(&nr_route.callsign,
680 nr_route.mnemonic,
681 &nr_route.neighbour,
682 nr_call_to_digi(&digi, nr_route.ndigis,
683 nr_route.digipeaters),
684 dev, nr_route.quality,
685 nr_route.obs_count);
686 break;
687 case NETROM_NEIGH:
688 ret = nr_add_neigh(&nr_route.callsign,
689 nr_call_to_digi(&digi, nr_route.ndigis,
690 nr_route.digipeaters),
691 dev, nr_route.quality);
692 break;
693 default:
694 ret = -EINVAL;
695 }
696 dev_put(dev);
697 return ret;
698
699 case SIOCDELRT:
700 if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct)))
701 return -EFAULT;
702 if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL)
703 return -EINVAL;
704 switch (nr_route.type) {
705 case NETROM_NODE:
706 ret = nr_del_node(&nr_route.callsign,
707 &nr_route.neighbour, dev);
708 break;
709 case NETROM_NEIGH:
710 ret = nr_del_neigh(&nr_route.callsign,
711 dev, nr_route.quality);
712 break;
713 default:
714 ret = -EINVAL;
715 }
716 dev_put(dev);
717 return ret;
718
719 case SIOCNRDECOBS:
720 return nr_dec_obs();
721
722 default:
723 return -EINVAL;
724 }
725
726 return 0;
727}
728
729/*
730 * A level 2 link has timed out, therefore it appears to be a poor link,
731 * then don't use that neighbour until it is reset.
732 */
733void nr_link_failed(ax25_cb *ax25, int reason)
734{
735 struct nr_neigh *s, *nr_neigh = NULL;
736 struct nr_node *nr_node = NULL;
737
738 spin_lock_bh(&nr_neigh_list_lock);
739 nr_neigh_for_each(s, &nr_neigh_list) {
740 if (s->ax25 == ax25) {
741 nr_neigh_hold(s);
742 nr_neigh = s;
743 break;
744 }
745 }
746 spin_unlock_bh(&nr_neigh_list_lock);
747
748 if (nr_neigh == NULL)
749 return;
750
751 nr_neigh->ax25 = NULL;
752 ax25_cb_put(ax25);
753
754 if (++nr_neigh->failed < sysctl_netrom_link_fails_count) {
755 nr_neigh_put(nr_neigh);
756 return;
757 }
758 spin_lock_bh(&nr_node_list_lock);
759 nr_node_for_each(nr_node, &nr_node_list) {
760 nr_node_lock(nr_node);
761 if (nr_node->which < nr_node->count &&
762 nr_node->routes[nr_node->which].neighbour == nr_neigh)
763 nr_node->which++;
764 nr_node_unlock(nr_node);
765 }
766 spin_unlock_bh(&nr_node_list_lock);
767 nr_neigh_put(nr_neigh);
768}
769
770/*
771 * Route a frame to an appropriate AX.25 connection. A NULL ax25_cb
772 * indicates an internally generated frame.
773 */
774int nr_route_frame(struct sk_buff *skb, ax25_cb *ax25)
775{
776 ax25_address *nr_src, *nr_dest;
777 struct nr_neigh *nr_neigh;
778 struct nr_node *nr_node;
779 struct net_device *dev;
780 unsigned char *dptr;
781 ax25_cb *ax25s;
782 int ret;
783 struct sk_buff *skbn;
784
785
786 nr_src = (ax25_address *)(skb->data + 0);
787 nr_dest = (ax25_address *)(skb->data + 7);
788
789 if (ax25 != NULL) {
790 ret = nr_add_node(nr_src, "", &ax25->dest_addr, ax25->digipeat,
791 ax25->ax25_dev->dev, 0,
792 sysctl_netrom_obsolescence_count_initialiser);
793 if (ret)
794 return ret;
795 }
796
797 if ((dev = nr_dev_get(nr_dest)) != NULL) { /* Its for me */
798 if (ax25 == NULL) /* Its from me */
799 ret = nr_loopback_queue(skb);
800 else
801 ret = nr_rx_frame(skb, dev);
802 dev_put(dev);
803 return ret;
804 }
805
806 if (!sysctl_netrom_routing_control && ax25 != NULL)
807 return 0;
808
809 /* Its Time-To-Live has expired */
810 if (skb->data[14] == 1) {
811 return 0;
812 }
813
814 nr_node = nr_node_get(nr_dest);
815 if (nr_node == NULL)
816 return 0;
817 nr_node_lock(nr_node);
818
819 if (nr_node->which >= nr_node->count) {
820 nr_node_unlock(nr_node);
821 nr_node_put(nr_node);
822 return 0;
823 }
824
825 nr_neigh = nr_node->routes[nr_node->which].neighbour;
826
827 if ((dev = nr_dev_first()) == NULL) {
828 nr_node_unlock(nr_node);
829 nr_node_put(nr_node);
830 return 0;
831 }
832
833 /* We are going to change the netrom headers so we should get our
834 own skb, we also did not know until now how much header space
835 we had to reserve... - RXQ */
836 if ((skbn=skb_copy_expand(skb, dev->hard_header_len, 0, GFP_ATOMIC)) == NULL) {
837 nr_node_unlock(nr_node);
838 nr_node_put(nr_node);
839 dev_put(dev);
840 return 0;
841 }
842 kfree_skb(skb);
843 skb=skbn;
844 skb->data[14]--;
845
846 dptr = skb_push(skb, 1);
847 *dptr = AX25_P_NETROM;
848
849 ax25s = nr_neigh->ax25;
850 nr_neigh->ax25 = ax25_send_frame(skb, 256,
851 (ax25_address *)dev->dev_addr,
852 &nr_neigh->callsign,
853 nr_neigh->digipeat, nr_neigh->dev);
854 if (ax25s)
855 ax25_cb_put(ax25s);
856
857 dev_put(dev);
858 ret = (nr_neigh->ax25 != NULL);
859 nr_node_unlock(nr_node);
860 nr_node_put(nr_node);
861
862 return ret;
863}
864
865#ifdef CONFIG_PROC_FS
866
867static void *nr_node_start(struct seq_file *seq, loff_t *pos)
868{
869 spin_lock_bh(&nr_node_list_lock);
870 return seq_hlist_start_head(&nr_node_list, *pos);
871}
872
873static void *nr_node_next(struct seq_file *seq, void *v, loff_t *pos)
874{
875 return seq_hlist_next(v, &nr_node_list, pos);
876}
877
878static void nr_node_stop(struct seq_file *seq, void *v)
879{
880 spin_unlock_bh(&nr_node_list_lock);
881}
882
883static int nr_node_show(struct seq_file *seq, void *v)
884{
885 char buf[11];
886 int i;
887
888 if (v == SEQ_START_TOKEN)
889 seq_puts(seq,
890 "callsign mnemonic w n qual obs neigh qual obs neigh qual obs neigh\n");
891 else {
892 struct nr_node *nr_node = hlist_entry(v, struct nr_node,
893 node_node);
894
895 nr_node_lock(nr_node);
896 seq_printf(seq, "%-9s %-7s %d %d",
897 ax2asc(buf, &nr_node->callsign),
898 (nr_node->mnemonic[0] == '\0') ? "*" : nr_node->mnemonic,
899 nr_node->which + 1,
900 nr_node->count);
901
902 for (i = 0; i < nr_node->count; i++) {
903 seq_printf(seq, " %3d %d %05d",
904 nr_node->routes[i].quality,
905 nr_node->routes[i].obs_count,
906 nr_node->routes[i].neighbour->number);
907 }
908 nr_node_unlock(nr_node);
909
910 seq_puts(seq, "\n");
911 }
912 return 0;
913}
914
915static const struct seq_operations nr_node_seqops = {
916 .start = nr_node_start,
917 .next = nr_node_next,
918 .stop = nr_node_stop,
919 .show = nr_node_show,
920};
921
922static int nr_node_info_open(struct inode *inode, struct file *file)
923{
924 return seq_open(file, &nr_node_seqops);
925}
926
927const struct file_operations nr_nodes_fops = {
928 .owner = THIS_MODULE,
929 .open = nr_node_info_open,
930 .read = seq_read,
931 .llseek = seq_lseek,
932 .release = seq_release,
933};
934
935static void *nr_neigh_start(struct seq_file *seq, loff_t *pos)
936{
937 spin_lock_bh(&nr_neigh_list_lock);
938 return seq_hlist_start_head(&nr_neigh_list, *pos);
939}
940
941static void *nr_neigh_next(struct seq_file *seq, void *v, loff_t *pos)
942{
943 return seq_hlist_next(v, &nr_neigh_list, pos);
944}
945
946static void nr_neigh_stop(struct seq_file *seq, void *v)
947{
948 spin_unlock_bh(&nr_neigh_list_lock);
949}
950
951static int nr_neigh_show(struct seq_file *seq, void *v)
952{
953 char buf[11];
954 int i;
955
956 if (v == SEQ_START_TOKEN)
957 seq_puts(seq, "addr callsign dev qual lock count failed digipeaters\n");
958 else {
959 struct nr_neigh *nr_neigh;
960
961 nr_neigh = hlist_entry(v, struct nr_neigh, neigh_node);
962 seq_printf(seq, "%05d %-9s %-4s %3d %d %3d %3d",
963 nr_neigh->number,
964 ax2asc(buf, &nr_neigh->callsign),
965 nr_neigh->dev ? nr_neigh->dev->name : "???",
966 nr_neigh->quality,
967 nr_neigh->locked,
968 nr_neigh->count,
969 nr_neigh->failed);
970
971 if (nr_neigh->digipeat != NULL) {
972 for (i = 0; i < nr_neigh->digipeat->ndigi; i++)
973 seq_printf(seq, " %s",
974 ax2asc(buf, &nr_neigh->digipeat->calls[i]));
975 }
976
977 seq_puts(seq, "\n");
978 }
979 return 0;
980}
981
982static const struct seq_operations nr_neigh_seqops = {
983 .start = nr_neigh_start,
984 .next = nr_neigh_next,
985 .stop = nr_neigh_stop,
986 .show = nr_neigh_show,
987};
988
989static int nr_neigh_info_open(struct inode *inode, struct file *file)
990{
991 return seq_open(file, &nr_neigh_seqops);
992}
993
994const struct file_operations nr_neigh_fops = {
995 .owner = THIS_MODULE,
996 .open = nr_neigh_info_open,
997 .read = seq_read,
998 .llseek = seq_lseek,
999 .release = seq_release,
1000};
1001
1002#endif
1003
1004/*
1005 * Free all memory associated with the nodes and routes lists.
1006 */
1007void __exit nr_rt_free(void)
1008{
1009 struct nr_neigh *s = NULL;
1010 struct nr_node *t = NULL;
1011 struct hlist_node *nodet;
1012
1013 spin_lock_bh(&nr_neigh_list_lock);
1014 spin_lock_bh(&nr_node_list_lock);
1015 nr_node_for_each_safe(t, nodet, &nr_node_list) {
1016 nr_node_lock(t);
1017 nr_remove_node_locked(t);
1018 nr_node_unlock(t);
1019 }
1020 nr_neigh_for_each_safe(s, nodet, &nr_neigh_list) {
1021 while(s->count) {
1022 s->count--;
1023 nr_neigh_put(s);
1024 }
1025 nr_remove_neigh_locked(s);
1026 }
1027 spin_unlock_bh(&nr_node_list_lock);
1028 spin_unlock_bh(&nr_neigh_list_lock);
1029}
1/*
2 * This program is free software; you can redistribute it and/or modify
3 * it under the terms of the GNU General Public License as published by
4 * the Free Software Foundation; either version 2 of the License, or
5 * (at your option) any later version.
6 *
7 * Copyright Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
8 * Copyright Alan Cox GW4PTS (alan@lxorguk.ukuu.org.uk)
9 * Copyright Tomi Manninen OH2BNS (oh2bns@sral.fi)
10 */
11#include <linux/errno.h>
12#include <linux/types.h>
13#include <linux/socket.h>
14#include <linux/in.h>
15#include <linux/kernel.h>
16#include <linux/timer.h>
17#include <linux/string.h>
18#include <linux/sockios.h>
19#include <linux/net.h>
20#include <linux/slab.h>
21#include <net/ax25.h>
22#include <linux/inet.h>
23#include <linux/netdevice.h>
24#include <net/arp.h>
25#include <linux/if_arp.h>
26#include <linux/skbuff.h>
27#include <net/sock.h>
28#include <asm/uaccess.h>
29#include <linux/fcntl.h>
30#include <linux/termios.h> /* For TIOCINQ/OUTQ */
31#include <linux/mm.h>
32#include <linux/interrupt.h>
33#include <linux/notifier.h>
34#include <linux/netfilter.h>
35#include <linux/init.h>
36#include <linux/spinlock.h>
37#include <net/netrom.h>
38#include <linux/seq_file.h>
39#include <linux/export.h>
40
41static unsigned int nr_neigh_no = 1;
42
43static HLIST_HEAD(nr_node_list);
44static DEFINE_SPINLOCK(nr_node_list_lock);
45static HLIST_HEAD(nr_neigh_list);
46static DEFINE_SPINLOCK(nr_neigh_list_lock);
47
48static struct nr_node *nr_node_get(ax25_address *callsign)
49{
50 struct nr_node *found = NULL;
51 struct nr_node *nr_node;
52 struct hlist_node *node;
53
54 spin_lock_bh(&nr_node_list_lock);
55 nr_node_for_each(nr_node, node, &nr_node_list)
56 if (ax25cmp(callsign, &nr_node->callsign) == 0) {
57 nr_node_hold(nr_node);
58 found = nr_node;
59 break;
60 }
61 spin_unlock_bh(&nr_node_list_lock);
62 return found;
63}
64
65static struct nr_neigh *nr_neigh_get_dev(ax25_address *callsign,
66 struct net_device *dev)
67{
68 struct nr_neigh *found = NULL;
69 struct nr_neigh *nr_neigh;
70 struct hlist_node *node;
71
72 spin_lock_bh(&nr_neigh_list_lock);
73 nr_neigh_for_each(nr_neigh, node, &nr_neigh_list)
74 if (ax25cmp(callsign, &nr_neigh->callsign) == 0 &&
75 nr_neigh->dev == dev) {
76 nr_neigh_hold(nr_neigh);
77 found = nr_neigh;
78 break;
79 }
80 spin_unlock_bh(&nr_neigh_list_lock);
81 return found;
82}
83
84static void nr_remove_neigh(struct nr_neigh *);
85
86/*
87 * Add a new route to a node, and in the process add the node and the
88 * neighbour if it is new.
89 */
90static int __must_check nr_add_node(ax25_address *nr, const char *mnemonic,
91 ax25_address *ax25, ax25_digi *ax25_digi, struct net_device *dev,
92 int quality, int obs_count)
93{
94 struct nr_node *nr_node;
95 struct nr_neigh *nr_neigh;
96 struct nr_route nr_route;
97 int i, found;
98 struct net_device *odev;
99
100 if ((odev=nr_dev_get(nr)) != NULL) { /* Can't add routes to ourself */
101 dev_put(odev);
102 return -EINVAL;
103 }
104
105 nr_node = nr_node_get(nr);
106
107 nr_neigh = nr_neigh_get_dev(ax25, dev);
108
109 /*
110 * The L2 link to a neighbour has failed in the past
111 * and now a frame comes from this neighbour. We assume
112 * it was a temporary trouble with the link and reset the
113 * routes now (and not wait for a node broadcast).
114 */
115 if (nr_neigh != NULL && nr_neigh->failed != 0 && quality == 0) {
116 struct nr_node *nr_nodet;
117 struct hlist_node *node;
118
119 spin_lock_bh(&nr_node_list_lock);
120 nr_node_for_each(nr_nodet, node, &nr_node_list) {
121 nr_node_lock(nr_nodet);
122 for (i = 0; i < nr_nodet->count; i++)
123 if (nr_nodet->routes[i].neighbour == nr_neigh)
124 if (i < nr_nodet->which)
125 nr_nodet->which = i;
126 nr_node_unlock(nr_nodet);
127 }
128 spin_unlock_bh(&nr_node_list_lock);
129 }
130
131 if (nr_neigh != NULL)
132 nr_neigh->failed = 0;
133
134 if (quality == 0 && nr_neigh != NULL && nr_node != NULL) {
135 nr_neigh_put(nr_neigh);
136 nr_node_put(nr_node);
137 return 0;
138 }
139
140 if (nr_neigh == NULL) {
141 if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL) {
142 if (nr_node)
143 nr_node_put(nr_node);
144 return -ENOMEM;
145 }
146
147 nr_neigh->callsign = *ax25;
148 nr_neigh->digipeat = NULL;
149 nr_neigh->ax25 = NULL;
150 nr_neigh->dev = dev;
151 nr_neigh->quality = sysctl_netrom_default_path_quality;
152 nr_neigh->locked = 0;
153 nr_neigh->count = 0;
154 nr_neigh->number = nr_neigh_no++;
155 nr_neigh->failed = 0;
156 atomic_set(&nr_neigh->refcount, 1);
157
158 if (ax25_digi != NULL && ax25_digi->ndigi > 0) {
159 nr_neigh->digipeat = kmemdup(ax25_digi,
160 sizeof(*ax25_digi),
161 GFP_KERNEL);
162 if (nr_neigh->digipeat == NULL) {
163 kfree(nr_neigh);
164 if (nr_node)
165 nr_node_put(nr_node);
166 return -ENOMEM;
167 }
168 }
169
170 spin_lock_bh(&nr_neigh_list_lock);
171 hlist_add_head(&nr_neigh->neigh_node, &nr_neigh_list);
172 nr_neigh_hold(nr_neigh);
173 spin_unlock_bh(&nr_neigh_list_lock);
174 }
175
176 if (quality != 0 && ax25cmp(nr, ax25) == 0 && !nr_neigh->locked)
177 nr_neigh->quality = quality;
178
179 if (nr_node == NULL) {
180 if ((nr_node = kmalloc(sizeof(*nr_node), GFP_ATOMIC)) == NULL) {
181 if (nr_neigh)
182 nr_neigh_put(nr_neigh);
183 return -ENOMEM;
184 }
185
186 nr_node->callsign = *nr;
187 strcpy(nr_node->mnemonic, mnemonic);
188
189 nr_node->which = 0;
190 nr_node->count = 1;
191 atomic_set(&nr_node->refcount, 1);
192 spin_lock_init(&nr_node->node_lock);
193
194 nr_node->routes[0].quality = quality;
195 nr_node->routes[0].obs_count = obs_count;
196 nr_node->routes[0].neighbour = nr_neigh;
197
198 nr_neigh_hold(nr_neigh);
199 nr_neigh->count++;
200
201 spin_lock_bh(&nr_node_list_lock);
202 hlist_add_head(&nr_node->node_node, &nr_node_list);
203 /* refcount initialized at 1 */
204 spin_unlock_bh(&nr_node_list_lock);
205
206 return 0;
207 }
208 nr_node_lock(nr_node);
209
210 if (quality != 0)
211 strcpy(nr_node->mnemonic, mnemonic);
212
213 for (found = 0, i = 0; i < nr_node->count; i++) {
214 if (nr_node->routes[i].neighbour == nr_neigh) {
215 nr_node->routes[i].quality = quality;
216 nr_node->routes[i].obs_count = obs_count;
217 found = 1;
218 break;
219 }
220 }
221
222 if (!found) {
223 /* We have space at the bottom, slot it in */
224 if (nr_node->count < 3) {
225 nr_node->routes[2] = nr_node->routes[1];
226 nr_node->routes[1] = nr_node->routes[0];
227
228 nr_node->routes[0].quality = quality;
229 nr_node->routes[0].obs_count = obs_count;
230 nr_node->routes[0].neighbour = nr_neigh;
231
232 nr_node->which++;
233 nr_node->count++;
234 nr_neigh_hold(nr_neigh);
235 nr_neigh->count++;
236 } else {
237 /* It must be better than the worst */
238 if (quality > nr_node->routes[2].quality) {
239 nr_node->routes[2].neighbour->count--;
240 nr_neigh_put(nr_node->routes[2].neighbour);
241
242 if (nr_node->routes[2].neighbour->count == 0 && !nr_node->routes[2].neighbour->locked)
243 nr_remove_neigh(nr_node->routes[2].neighbour);
244
245 nr_node->routes[2].quality = quality;
246 nr_node->routes[2].obs_count = obs_count;
247 nr_node->routes[2].neighbour = nr_neigh;
248
249 nr_neigh_hold(nr_neigh);
250 nr_neigh->count++;
251 }
252 }
253 }
254
255 /* Now re-sort the routes in quality order */
256 switch (nr_node->count) {
257 case 3:
258 if (nr_node->routes[1].quality > nr_node->routes[0].quality) {
259 switch (nr_node->which) {
260 case 0:
261 nr_node->which = 1;
262 break;
263 case 1:
264 nr_node->which = 0;
265 break;
266 }
267 nr_route = nr_node->routes[0];
268 nr_node->routes[0] = nr_node->routes[1];
269 nr_node->routes[1] = nr_route;
270 }
271 if (nr_node->routes[2].quality > nr_node->routes[1].quality) {
272 switch (nr_node->which) {
273 case 1: nr_node->which = 2;
274 break;
275
276 case 2: nr_node->which = 1;
277 break;
278
279 default:
280 break;
281 }
282 nr_route = nr_node->routes[1];
283 nr_node->routes[1] = nr_node->routes[2];
284 nr_node->routes[2] = nr_route;
285 }
286 case 2:
287 if (nr_node->routes[1].quality > nr_node->routes[0].quality) {
288 switch (nr_node->which) {
289 case 0: nr_node->which = 1;
290 break;
291
292 case 1: nr_node->which = 0;
293 break;
294
295 default: break;
296 }
297 nr_route = nr_node->routes[0];
298 nr_node->routes[0] = nr_node->routes[1];
299 nr_node->routes[1] = nr_route;
300 }
301 case 1:
302 break;
303 }
304
305 for (i = 0; i < nr_node->count; i++) {
306 if (nr_node->routes[i].neighbour == nr_neigh) {
307 if (i < nr_node->which)
308 nr_node->which = i;
309 break;
310 }
311 }
312
313 nr_neigh_put(nr_neigh);
314 nr_node_unlock(nr_node);
315 nr_node_put(nr_node);
316 return 0;
317}
318
319static inline void __nr_remove_node(struct nr_node *nr_node)
320{
321 hlist_del_init(&nr_node->node_node);
322 nr_node_put(nr_node);
323}
324
325#define nr_remove_node_locked(__node) \
326 __nr_remove_node(__node)
327
328static void nr_remove_node(struct nr_node *nr_node)
329{
330 spin_lock_bh(&nr_node_list_lock);
331 __nr_remove_node(nr_node);
332 spin_unlock_bh(&nr_node_list_lock);
333}
334
335static inline void __nr_remove_neigh(struct nr_neigh *nr_neigh)
336{
337 hlist_del_init(&nr_neigh->neigh_node);
338 nr_neigh_put(nr_neigh);
339}
340
341#define nr_remove_neigh_locked(__neigh) \
342 __nr_remove_neigh(__neigh)
343
344static void nr_remove_neigh(struct nr_neigh *nr_neigh)
345{
346 spin_lock_bh(&nr_neigh_list_lock);
347 __nr_remove_neigh(nr_neigh);
348 spin_unlock_bh(&nr_neigh_list_lock);
349}
350
351/*
352 * "Delete" a node. Strictly speaking remove a route to a node. The node
353 * is only deleted if no routes are left to it.
354 */
355static int nr_del_node(ax25_address *callsign, ax25_address *neighbour, struct net_device *dev)
356{
357 struct nr_node *nr_node;
358 struct nr_neigh *nr_neigh;
359 int i;
360
361 nr_node = nr_node_get(callsign);
362
363 if (nr_node == NULL)
364 return -EINVAL;
365
366 nr_neigh = nr_neigh_get_dev(neighbour, dev);
367
368 if (nr_neigh == NULL) {
369 nr_node_put(nr_node);
370 return -EINVAL;
371 }
372
373 nr_node_lock(nr_node);
374 for (i = 0; i < nr_node->count; i++) {
375 if (nr_node->routes[i].neighbour == nr_neigh) {
376 nr_neigh->count--;
377 nr_neigh_put(nr_neigh);
378
379 if (nr_neigh->count == 0 && !nr_neigh->locked)
380 nr_remove_neigh(nr_neigh);
381 nr_neigh_put(nr_neigh);
382
383 nr_node->count--;
384
385 if (nr_node->count == 0) {
386 nr_remove_node(nr_node);
387 } else {
388 switch (i) {
389 case 0:
390 nr_node->routes[0] = nr_node->routes[1];
391 case 1:
392 nr_node->routes[1] = nr_node->routes[2];
393 case 2:
394 break;
395 }
396 nr_node_put(nr_node);
397 }
398 nr_node_unlock(nr_node);
399
400 return 0;
401 }
402 }
403 nr_neigh_put(nr_neigh);
404 nr_node_unlock(nr_node);
405 nr_node_put(nr_node);
406
407 return -EINVAL;
408}
409
410/*
411 * Lock a neighbour with a quality.
412 */
413static int __must_check nr_add_neigh(ax25_address *callsign,
414 ax25_digi *ax25_digi, struct net_device *dev, unsigned int quality)
415{
416 struct nr_neigh *nr_neigh;
417
418 nr_neigh = nr_neigh_get_dev(callsign, dev);
419 if (nr_neigh) {
420 nr_neigh->quality = quality;
421 nr_neigh->locked = 1;
422 nr_neigh_put(nr_neigh);
423 return 0;
424 }
425
426 if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL)
427 return -ENOMEM;
428
429 nr_neigh->callsign = *callsign;
430 nr_neigh->digipeat = NULL;
431 nr_neigh->ax25 = NULL;
432 nr_neigh->dev = dev;
433 nr_neigh->quality = quality;
434 nr_neigh->locked = 1;
435 nr_neigh->count = 0;
436 nr_neigh->number = nr_neigh_no++;
437 nr_neigh->failed = 0;
438 atomic_set(&nr_neigh->refcount, 1);
439
440 if (ax25_digi != NULL && ax25_digi->ndigi > 0) {
441 nr_neigh->digipeat = kmemdup(ax25_digi, sizeof(*ax25_digi),
442 GFP_KERNEL);
443 if (nr_neigh->digipeat == NULL) {
444 kfree(nr_neigh);
445 return -ENOMEM;
446 }
447 }
448
449 spin_lock_bh(&nr_neigh_list_lock);
450 hlist_add_head(&nr_neigh->neigh_node, &nr_neigh_list);
451 /* refcount is initialized at 1 */
452 spin_unlock_bh(&nr_neigh_list_lock);
453
454 return 0;
455}
456
457/*
458 * "Delete" a neighbour. The neighbour is only removed if the number
459 * of nodes that may use it is zero.
460 */
461static int nr_del_neigh(ax25_address *callsign, struct net_device *dev, unsigned int quality)
462{
463 struct nr_neigh *nr_neigh;
464
465 nr_neigh = nr_neigh_get_dev(callsign, dev);
466
467 if (nr_neigh == NULL) return -EINVAL;
468
469 nr_neigh->quality = quality;
470 nr_neigh->locked = 0;
471
472 if (nr_neigh->count == 0)
473 nr_remove_neigh(nr_neigh);
474 nr_neigh_put(nr_neigh);
475
476 return 0;
477}
478
479/*
480 * Decrement the obsolescence count by one. If a route is reduced to a
481 * count of zero, remove it. Also remove any unlocked neighbours with
482 * zero nodes routing via it.
483 */
484static int nr_dec_obs(void)
485{
486 struct nr_neigh *nr_neigh;
487 struct nr_node *s;
488 struct hlist_node *node, *nodet;
489 int i;
490
491 spin_lock_bh(&nr_node_list_lock);
492 nr_node_for_each_safe(s, node, nodet, &nr_node_list) {
493 nr_node_lock(s);
494 for (i = 0; i < s->count; i++) {
495 switch (s->routes[i].obs_count) {
496 case 0: /* A locked entry */
497 break;
498
499 case 1: /* From 1 -> 0 */
500 nr_neigh = s->routes[i].neighbour;
501
502 nr_neigh->count--;
503 nr_neigh_put(nr_neigh);
504
505 if (nr_neigh->count == 0 && !nr_neigh->locked)
506 nr_remove_neigh(nr_neigh);
507
508 s->count--;
509
510 switch (i) {
511 case 0:
512 s->routes[0] = s->routes[1];
513 /* Fallthrough */
514 case 1:
515 s->routes[1] = s->routes[2];
516 case 2:
517 break;
518 }
519 break;
520
521 default:
522 s->routes[i].obs_count--;
523 break;
524
525 }
526 }
527
528 if (s->count <= 0)
529 nr_remove_node_locked(s);
530 nr_node_unlock(s);
531 }
532 spin_unlock_bh(&nr_node_list_lock);
533
534 return 0;
535}
536
537/*
538 * A device has been removed. Remove its routes and neighbours.
539 */
540void nr_rt_device_down(struct net_device *dev)
541{
542 struct nr_neigh *s;
543 struct hlist_node *node, *nodet, *node2, *node2t;
544 struct nr_node *t;
545 int i;
546
547 spin_lock_bh(&nr_neigh_list_lock);
548 nr_neigh_for_each_safe(s, node, nodet, &nr_neigh_list) {
549 if (s->dev == dev) {
550 spin_lock_bh(&nr_node_list_lock);
551 nr_node_for_each_safe(t, node2, node2t, &nr_node_list) {
552 nr_node_lock(t);
553 for (i = 0; i < t->count; i++) {
554 if (t->routes[i].neighbour == s) {
555 t->count--;
556
557 switch (i) {
558 case 0:
559 t->routes[0] = t->routes[1];
560 case 1:
561 t->routes[1] = t->routes[2];
562 case 2:
563 break;
564 }
565 }
566 }
567
568 if (t->count <= 0)
569 nr_remove_node_locked(t);
570 nr_node_unlock(t);
571 }
572 spin_unlock_bh(&nr_node_list_lock);
573
574 nr_remove_neigh_locked(s);
575 }
576 }
577 spin_unlock_bh(&nr_neigh_list_lock);
578}
579
580/*
581 * Check that the device given is a valid AX.25 interface that is "up".
582 * Or a valid ethernet interface with an AX.25 callsign binding.
583 */
584static struct net_device *nr_ax25_dev_get(char *devname)
585{
586 struct net_device *dev;
587
588 if ((dev = dev_get_by_name(&init_net, devname)) == NULL)
589 return NULL;
590
591 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_AX25)
592 return dev;
593
594 dev_put(dev);
595 return NULL;
596}
597
598/*
599 * Find the first active NET/ROM device, usually "nr0".
600 */
601struct net_device *nr_dev_first(void)
602{
603 struct net_device *dev, *first = NULL;
604
605 rcu_read_lock();
606 for_each_netdev_rcu(&init_net, dev) {
607 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM)
608 if (first == NULL || strncmp(dev->name, first->name, 3) < 0)
609 first = dev;
610 }
611 if (first)
612 dev_hold(first);
613 rcu_read_unlock();
614
615 return first;
616}
617
618/*
619 * Find the NET/ROM device for the given callsign.
620 */
621struct net_device *nr_dev_get(ax25_address *addr)
622{
623 struct net_device *dev;
624
625 rcu_read_lock();
626 for_each_netdev_rcu(&init_net, dev) {
627 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM &&
628 ax25cmp(addr, (ax25_address *)dev->dev_addr) == 0) {
629 dev_hold(dev);
630 goto out;
631 }
632 }
633 dev = NULL;
634out:
635 rcu_read_unlock();
636 return dev;
637}
638
639static ax25_digi *nr_call_to_digi(ax25_digi *digi, int ndigis,
640 ax25_address *digipeaters)
641{
642 int i;
643
644 if (ndigis == 0)
645 return NULL;
646
647 for (i = 0; i < ndigis; i++) {
648 digi->calls[i] = digipeaters[i];
649 digi->repeated[i] = 0;
650 }
651
652 digi->ndigi = ndigis;
653 digi->lastrepeat = -1;
654
655 return digi;
656}
657
658/*
659 * Handle the ioctls that control the routing functions.
660 */
661int nr_rt_ioctl(unsigned int cmd, void __user *arg)
662{
663 struct nr_route_struct nr_route;
664 struct net_device *dev;
665 ax25_digi digi;
666 int ret;
667
668 switch (cmd) {
669 case SIOCADDRT:
670 if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct)))
671 return -EFAULT;
672 if (nr_route.ndigis > AX25_MAX_DIGIS)
673 return -EINVAL;
674 if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL)
675 return -EINVAL;
676 switch (nr_route.type) {
677 case NETROM_NODE:
678 if (strnlen(nr_route.mnemonic, 7) == 7) {
679 ret = -EINVAL;
680 break;
681 }
682
683 ret = nr_add_node(&nr_route.callsign,
684 nr_route.mnemonic,
685 &nr_route.neighbour,
686 nr_call_to_digi(&digi, nr_route.ndigis,
687 nr_route.digipeaters),
688 dev, nr_route.quality,
689 nr_route.obs_count);
690 break;
691 case NETROM_NEIGH:
692 ret = nr_add_neigh(&nr_route.callsign,
693 nr_call_to_digi(&digi, nr_route.ndigis,
694 nr_route.digipeaters),
695 dev, nr_route.quality);
696 break;
697 default:
698 ret = -EINVAL;
699 }
700 dev_put(dev);
701 return ret;
702
703 case SIOCDELRT:
704 if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct)))
705 return -EFAULT;
706 if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL)
707 return -EINVAL;
708 switch (nr_route.type) {
709 case NETROM_NODE:
710 ret = nr_del_node(&nr_route.callsign,
711 &nr_route.neighbour, dev);
712 break;
713 case NETROM_NEIGH:
714 ret = nr_del_neigh(&nr_route.callsign,
715 dev, nr_route.quality);
716 break;
717 default:
718 ret = -EINVAL;
719 }
720 dev_put(dev);
721 return ret;
722
723 case SIOCNRDECOBS:
724 return nr_dec_obs();
725
726 default:
727 return -EINVAL;
728 }
729
730 return 0;
731}
732
733/*
734 * A level 2 link has timed out, therefore it appears to be a poor link,
735 * then don't use that neighbour until it is reset.
736 */
737void nr_link_failed(ax25_cb *ax25, int reason)
738{
739 struct nr_neigh *s, *nr_neigh = NULL;
740 struct hlist_node *node;
741 struct nr_node *nr_node = NULL;
742
743 spin_lock_bh(&nr_neigh_list_lock);
744 nr_neigh_for_each(s, node, &nr_neigh_list) {
745 if (s->ax25 == ax25) {
746 nr_neigh_hold(s);
747 nr_neigh = s;
748 break;
749 }
750 }
751 spin_unlock_bh(&nr_neigh_list_lock);
752
753 if (nr_neigh == NULL)
754 return;
755
756 nr_neigh->ax25 = NULL;
757 ax25_cb_put(ax25);
758
759 if (++nr_neigh->failed < sysctl_netrom_link_fails_count) {
760 nr_neigh_put(nr_neigh);
761 return;
762 }
763 spin_lock_bh(&nr_node_list_lock);
764 nr_node_for_each(nr_node, node, &nr_node_list) {
765 nr_node_lock(nr_node);
766 if (nr_node->which < nr_node->count &&
767 nr_node->routes[nr_node->which].neighbour == nr_neigh)
768 nr_node->which++;
769 nr_node_unlock(nr_node);
770 }
771 spin_unlock_bh(&nr_node_list_lock);
772 nr_neigh_put(nr_neigh);
773}
774
775/*
776 * Route a frame to an appropriate AX.25 connection. A NULL ax25_cb
777 * indicates an internally generated frame.
778 */
779int nr_route_frame(struct sk_buff *skb, ax25_cb *ax25)
780{
781 ax25_address *nr_src, *nr_dest;
782 struct nr_neigh *nr_neigh;
783 struct nr_node *nr_node;
784 struct net_device *dev;
785 unsigned char *dptr;
786 ax25_cb *ax25s;
787 int ret;
788 struct sk_buff *skbn;
789
790
791 nr_src = (ax25_address *)(skb->data + 0);
792 nr_dest = (ax25_address *)(skb->data + 7);
793
794 if (ax25 != NULL) {
795 ret = nr_add_node(nr_src, "", &ax25->dest_addr, ax25->digipeat,
796 ax25->ax25_dev->dev, 0,
797 sysctl_netrom_obsolescence_count_initialiser);
798 if (ret)
799 return ret;
800 }
801
802 if ((dev = nr_dev_get(nr_dest)) != NULL) { /* Its for me */
803 if (ax25 == NULL) /* Its from me */
804 ret = nr_loopback_queue(skb);
805 else
806 ret = nr_rx_frame(skb, dev);
807 dev_put(dev);
808 return ret;
809 }
810
811 if (!sysctl_netrom_routing_control && ax25 != NULL)
812 return 0;
813
814 /* Its Time-To-Live has expired */
815 if (skb->data[14] == 1) {
816 return 0;
817 }
818
819 nr_node = nr_node_get(nr_dest);
820 if (nr_node == NULL)
821 return 0;
822 nr_node_lock(nr_node);
823
824 if (nr_node->which >= nr_node->count) {
825 nr_node_unlock(nr_node);
826 nr_node_put(nr_node);
827 return 0;
828 }
829
830 nr_neigh = nr_node->routes[nr_node->which].neighbour;
831
832 if ((dev = nr_dev_first()) == NULL) {
833 nr_node_unlock(nr_node);
834 nr_node_put(nr_node);
835 return 0;
836 }
837
838 /* We are going to change the netrom headers so we should get our
839 own skb, we also did not know until now how much header space
840 we had to reserve... - RXQ */
841 if ((skbn=skb_copy_expand(skb, dev->hard_header_len, 0, GFP_ATOMIC)) == NULL) {
842 nr_node_unlock(nr_node);
843 nr_node_put(nr_node);
844 dev_put(dev);
845 return 0;
846 }
847 kfree_skb(skb);
848 skb=skbn;
849 skb->data[14]--;
850
851 dptr = skb_push(skb, 1);
852 *dptr = AX25_P_NETROM;
853
854 ax25s = nr_neigh->ax25;
855 nr_neigh->ax25 = ax25_send_frame(skb, 256,
856 (ax25_address *)dev->dev_addr,
857 &nr_neigh->callsign,
858 nr_neigh->digipeat, nr_neigh->dev);
859 if (ax25s)
860 ax25_cb_put(ax25s);
861
862 dev_put(dev);
863 ret = (nr_neigh->ax25 != NULL);
864 nr_node_unlock(nr_node);
865 nr_node_put(nr_node);
866
867 return ret;
868}
869
870#ifdef CONFIG_PROC_FS
871
872static void *nr_node_start(struct seq_file *seq, loff_t *pos)
873{
874 spin_lock_bh(&nr_node_list_lock);
875 return seq_hlist_start_head(&nr_node_list, *pos);
876}
877
878static void *nr_node_next(struct seq_file *seq, void *v, loff_t *pos)
879{
880 return seq_hlist_next(v, &nr_node_list, pos);
881}
882
883static void nr_node_stop(struct seq_file *seq, void *v)
884{
885 spin_unlock_bh(&nr_node_list_lock);
886}
887
888static int nr_node_show(struct seq_file *seq, void *v)
889{
890 char buf[11];
891 int i;
892
893 if (v == SEQ_START_TOKEN)
894 seq_puts(seq,
895 "callsign mnemonic w n qual obs neigh qual obs neigh qual obs neigh\n");
896 else {
897 struct nr_node *nr_node = hlist_entry(v, struct nr_node,
898 node_node);
899
900 nr_node_lock(nr_node);
901 seq_printf(seq, "%-9s %-7s %d %d",
902 ax2asc(buf, &nr_node->callsign),
903 (nr_node->mnemonic[0] == '\0') ? "*" : nr_node->mnemonic,
904 nr_node->which + 1,
905 nr_node->count);
906
907 for (i = 0; i < nr_node->count; i++) {
908 seq_printf(seq, " %3d %d %05d",
909 nr_node->routes[i].quality,
910 nr_node->routes[i].obs_count,
911 nr_node->routes[i].neighbour->number);
912 }
913 nr_node_unlock(nr_node);
914
915 seq_puts(seq, "\n");
916 }
917 return 0;
918}
919
920static const struct seq_operations nr_node_seqops = {
921 .start = nr_node_start,
922 .next = nr_node_next,
923 .stop = nr_node_stop,
924 .show = nr_node_show,
925};
926
927static int nr_node_info_open(struct inode *inode, struct file *file)
928{
929 return seq_open(file, &nr_node_seqops);
930}
931
932const struct file_operations nr_nodes_fops = {
933 .owner = THIS_MODULE,
934 .open = nr_node_info_open,
935 .read = seq_read,
936 .llseek = seq_lseek,
937 .release = seq_release,
938};
939
940static void *nr_neigh_start(struct seq_file *seq, loff_t *pos)
941{
942 spin_lock_bh(&nr_neigh_list_lock);
943 return seq_hlist_start_head(&nr_neigh_list, *pos);
944}
945
946static void *nr_neigh_next(struct seq_file *seq, void *v, loff_t *pos)
947{
948 return seq_hlist_next(v, &nr_neigh_list, pos);
949}
950
951static void nr_neigh_stop(struct seq_file *seq, void *v)
952{
953 spin_unlock_bh(&nr_neigh_list_lock);
954}
955
956static int nr_neigh_show(struct seq_file *seq, void *v)
957{
958 char buf[11];
959 int i;
960
961 if (v == SEQ_START_TOKEN)
962 seq_puts(seq, "addr callsign dev qual lock count failed digipeaters\n");
963 else {
964 struct nr_neigh *nr_neigh;
965
966 nr_neigh = hlist_entry(v, struct nr_neigh, neigh_node);
967 seq_printf(seq, "%05d %-9s %-4s %3d %d %3d %3d",
968 nr_neigh->number,
969 ax2asc(buf, &nr_neigh->callsign),
970 nr_neigh->dev ? nr_neigh->dev->name : "???",
971 nr_neigh->quality,
972 nr_neigh->locked,
973 nr_neigh->count,
974 nr_neigh->failed);
975
976 if (nr_neigh->digipeat != NULL) {
977 for (i = 0; i < nr_neigh->digipeat->ndigi; i++)
978 seq_printf(seq, " %s",
979 ax2asc(buf, &nr_neigh->digipeat->calls[i]));
980 }
981
982 seq_puts(seq, "\n");
983 }
984 return 0;
985}
986
987static const struct seq_operations nr_neigh_seqops = {
988 .start = nr_neigh_start,
989 .next = nr_neigh_next,
990 .stop = nr_neigh_stop,
991 .show = nr_neigh_show,
992};
993
994static int nr_neigh_info_open(struct inode *inode, struct file *file)
995{
996 return seq_open(file, &nr_neigh_seqops);
997}
998
999const struct file_operations nr_neigh_fops = {
1000 .owner = THIS_MODULE,
1001 .open = nr_neigh_info_open,
1002 .read = seq_read,
1003 .llseek = seq_lseek,
1004 .release = seq_release,
1005};
1006
1007#endif
1008
1009/*
1010 * Free all memory associated with the nodes and routes lists.
1011 */
1012void __exit nr_rt_free(void)
1013{
1014 struct nr_neigh *s = NULL;
1015 struct nr_node *t = NULL;
1016 struct hlist_node *node, *nodet;
1017
1018 spin_lock_bh(&nr_neigh_list_lock);
1019 spin_lock_bh(&nr_node_list_lock);
1020 nr_node_for_each_safe(t, node, nodet, &nr_node_list) {
1021 nr_node_lock(t);
1022 nr_remove_node_locked(t);
1023 nr_node_unlock(t);
1024 }
1025 nr_neigh_for_each_safe(s, node, nodet, &nr_neigh_list) {
1026 while(s->count) {
1027 s->count--;
1028 nr_neigh_put(s);
1029 }
1030 nr_remove_neigh_locked(s);
1031 }
1032 spin_unlock_bh(&nr_node_list_lock);
1033 spin_unlock_bh(&nr_neigh_list_lock);
1034}