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