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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *
4 * Copyright Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
5 * Copyright Alan Cox GW4PTS (alan@lxorguk.ukuu.org.uk)
6 * Copyright Tomi Manninen OH2BNS (oh2bns@sral.fi)
7 */
8#include <linux/errno.h>
9#include <linux/types.h>
10#include <linux/socket.h>
11#include <linux/in.h>
12#include <linux/kernel.h>
13#include <linux/timer.h>
14#include <linux/string.h>
15#include <linux/sockios.h>
16#include <linux/net.h>
17#include <linux/slab.h>
18#include <net/ax25.h>
19#include <linux/inet.h>
20#include <linux/netdevice.h>
21#include <net/arp.h>
22#include <linux/if_arp.h>
23#include <linux/skbuff.h>
24#include <net/sock.h>
25#include <linux/uaccess.h>
26#include <linux/fcntl.h>
27#include <linux/termios.h> /* For TIOCINQ/OUTQ */
28#include <linux/mm.h>
29#include <linux/interrupt.h>
30#include <linux/notifier.h>
31#include <linux/init.h>
32#include <linux/spinlock.h>
33#include <net/netrom.h>
34#include <linux/seq_file.h>
35#include <linux/export.h>
36
37static unsigned int nr_neigh_no = 1;
38
39static HLIST_HEAD(nr_node_list);
40static DEFINE_SPINLOCK(nr_node_list_lock);
41static HLIST_HEAD(nr_neigh_list);
42static DEFINE_SPINLOCK(nr_neigh_list_lock);
43
44static struct nr_node *nr_node_get(ax25_address *callsign)
45{
46 struct nr_node *found = NULL;
47 struct nr_node *nr_node;
48
49 spin_lock_bh(&nr_node_list_lock);
50 nr_node_for_each(nr_node, &nr_node_list)
51 if (ax25cmp(callsign, &nr_node->callsign) == 0) {
52 nr_node_hold(nr_node);
53 found = nr_node;
54 break;
55 }
56 spin_unlock_bh(&nr_node_list_lock);
57 return found;
58}
59
60static struct nr_neigh *nr_neigh_get_dev(ax25_address *callsign,
61 struct net_device *dev)
62{
63 struct nr_neigh *found = NULL;
64 struct nr_neigh *nr_neigh;
65
66 spin_lock_bh(&nr_neigh_list_lock);
67 nr_neigh_for_each(nr_neigh, &nr_neigh_list)
68 if (ax25cmp(callsign, &nr_neigh->callsign) == 0 &&
69 nr_neigh->dev == dev) {
70 nr_neigh_hold(nr_neigh);
71 found = nr_neigh;
72 break;
73 }
74 spin_unlock_bh(&nr_neigh_list_lock);
75 return found;
76}
77
78static void nr_remove_neigh(struct nr_neigh *);
79
80/* re-sort the routes in quality order. */
81static void re_sort_routes(struct nr_node *nr_node, int x, int y)
82{
83 if (nr_node->routes[y].quality > nr_node->routes[x].quality) {
84 if (nr_node->which == x)
85 nr_node->which = y;
86 else if (nr_node->which == y)
87 nr_node->which = x;
88
89 swap(nr_node->routes[x], nr_node->routes[y]);
90 }
91}
92
93/*
94 * Add a new route to a node, and in the process add the node and the
95 * neighbour if it is new.
96 */
97static int __must_check nr_add_node(ax25_address *nr, const char *mnemonic,
98 ax25_address *ax25, ax25_digi *ax25_digi, struct net_device *dev,
99 int quality, int obs_count)
100{
101 struct nr_node *nr_node;
102 struct nr_neigh *nr_neigh;
103 int i, found;
104 struct net_device *odev;
105
106 if ((odev=nr_dev_get(nr)) != NULL) { /* Can't add routes to ourself */
107 dev_put(odev);
108 return -EINVAL;
109 }
110
111 nr_node = nr_node_get(nr);
112
113 nr_neigh = nr_neigh_get_dev(ax25, dev);
114
115 /*
116 * The L2 link to a neighbour has failed in the past
117 * and now a frame comes from this neighbour. We assume
118 * it was a temporary trouble with the link and reset the
119 * routes now (and not wait for a node broadcast).
120 */
121 if (nr_neigh != NULL && nr_neigh->failed != 0 && quality == 0) {
122 struct nr_node *nr_nodet;
123
124 spin_lock_bh(&nr_node_list_lock);
125 nr_node_for_each(nr_nodet, &nr_node_list) {
126 nr_node_lock(nr_nodet);
127 for (i = 0; i < nr_nodet->count; i++)
128 if (nr_nodet->routes[i].neighbour == nr_neigh)
129 if (i < nr_nodet->which)
130 nr_nodet->which = i;
131 nr_node_unlock(nr_nodet);
132 }
133 spin_unlock_bh(&nr_node_list_lock);
134 }
135
136 if (nr_neigh != NULL)
137 nr_neigh->failed = 0;
138
139 if (quality == 0 && nr_neigh != NULL && nr_node != NULL) {
140 nr_neigh_put(nr_neigh);
141 nr_node_put(nr_node);
142 return 0;
143 }
144
145 if (nr_neigh == NULL) {
146 if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL) {
147 if (nr_node)
148 nr_node_put(nr_node);
149 return -ENOMEM;
150 }
151
152 nr_neigh->callsign = *ax25;
153 nr_neigh->digipeat = NULL;
154 nr_neigh->ax25 = NULL;
155 nr_neigh->dev = dev;
156 nr_neigh->quality = sysctl_netrom_default_path_quality;
157 nr_neigh->locked = 0;
158 nr_neigh->count = 0;
159 nr_neigh->number = nr_neigh_no++;
160 nr_neigh->failed = 0;
161 refcount_set(&nr_neigh->refcount, 1);
162
163 if (ax25_digi != NULL && ax25_digi->ndigi > 0) {
164 nr_neigh->digipeat = kmemdup(ax25_digi,
165 sizeof(*ax25_digi),
166 GFP_KERNEL);
167 if (nr_neigh->digipeat == NULL) {
168 kfree(nr_neigh);
169 if (nr_node)
170 nr_node_put(nr_node);
171 return -ENOMEM;
172 }
173 }
174
175 spin_lock_bh(&nr_neigh_list_lock);
176 hlist_add_head(&nr_neigh->neigh_node, &nr_neigh_list);
177 nr_neigh_hold(nr_neigh);
178 spin_unlock_bh(&nr_neigh_list_lock);
179 }
180
181 if (quality != 0 && ax25cmp(nr, ax25) == 0 && !nr_neigh->locked)
182 nr_neigh->quality = quality;
183
184 if (nr_node == NULL) {
185 if ((nr_node = kmalloc(sizeof(*nr_node), GFP_ATOMIC)) == NULL) {
186 if (nr_neigh)
187 nr_neigh_put(nr_neigh);
188 return -ENOMEM;
189 }
190
191 nr_node->callsign = *nr;
192 strcpy(nr_node->mnemonic, mnemonic);
193
194 nr_node->which = 0;
195 nr_node->count = 1;
196 refcount_set(&nr_node->refcount, 1);
197 spin_lock_init(&nr_node->node_lock);
198
199 nr_node->routes[0].quality = quality;
200 nr_node->routes[0].obs_count = obs_count;
201 nr_node->routes[0].neighbour = nr_neigh;
202
203 nr_neigh_hold(nr_neigh);
204 nr_neigh->count++;
205
206 spin_lock_bh(&nr_node_list_lock);
207 hlist_add_head(&nr_node->node_node, &nr_node_list);
208 /* refcount initialized at 1 */
209 spin_unlock_bh(&nr_node_list_lock);
210
211 nr_neigh_put(nr_neigh);
212 return 0;
213 }
214 nr_node_lock(nr_node);
215
216 if (quality != 0)
217 strcpy(nr_node->mnemonic, mnemonic);
218
219 for (found = 0, i = 0; i < nr_node->count; i++) {
220 if (nr_node->routes[i].neighbour == nr_neigh) {
221 nr_node->routes[i].quality = quality;
222 nr_node->routes[i].obs_count = obs_count;
223 found = 1;
224 break;
225 }
226 }
227
228 if (!found) {
229 /* We have space at the bottom, slot it in */
230 if (nr_node->count < 3) {
231 nr_node->routes[2] = nr_node->routes[1];
232 nr_node->routes[1] = nr_node->routes[0];
233
234 nr_node->routes[0].quality = quality;
235 nr_node->routes[0].obs_count = obs_count;
236 nr_node->routes[0].neighbour = nr_neigh;
237
238 nr_node->which++;
239 nr_node->count++;
240 nr_neigh_hold(nr_neigh);
241 nr_neigh->count++;
242 } else {
243 /* It must be better than the worst */
244 if (quality > nr_node->routes[2].quality) {
245 nr_node->routes[2].neighbour->count--;
246 nr_neigh_put(nr_node->routes[2].neighbour);
247
248 if (nr_node->routes[2].neighbour->count == 0 && !nr_node->routes[2].neighbour->locked)
249 nr_remove_neigh(nr_node->routes[2].neighbour);
250
251 nr_node->routes[2].quality = quality;
252 nr_node->routes[2].obs_count = obs_count;
253 nr_node->routes[2].neighbour = nr_neigh;
254
255 nr_neigh_hold(nr_neigh);
256 nr_neigh->count++;
257 }
258 }
259 }
260
261 /* Now re-sort the routes in quality order */
262 switch (nr_node->count) {
263 case 3:
264 re_sort_routes(nr_node, 0, 1);
265 re_sort_routes(nr_node, 1, 2);
266 fallthrough;
267 case 2:
268 re_sort_routes(nr_node, 0, 1);
269 break;
270 case 1:
271 break;
272 }
273
274 for (i = 0; i < nr_node->count; i++) {
275 if (nr_node->routes[i].neighbour == nr_neigh) {
276 if (i < nr_node->which)
277 nr_node->which = i;
278 break;
279 }
280 }
281
282 nr_neigh_put(nr_neigh);
283 nr_node_unlock(nr_node);
284 nr_node_put(nr_node);
285 return 0;
286}
287
288static inline void __nr_remove_node(struct nr_node *nr_node)
289{
290 hlist_del_init(&nr_node->node_node);
291 nr_node_put(nr_node);
292}
293
294#define nr_remove_node_locked(__node) \
295 __nr_remove_node(__node)
296
297static void nr_remove_node(struct nr_node *nr_node)
298{
299 spin_lock_bh(&nr_node_list_lock);
300 __nr_remove_node(nr_node);
301 spin_unlock_bh(&nr_node_list_lock);
302}
303
304static inline void __nr_remove_neigh(struct nr_neigh *nr_neigh)
305{
306 hlist_del_init(&nr_neigh->neigh_node);
307 nr_neigh_put(nr_neigh);
308}
309
310#define nr_remove_neigh_locked(__neigh) \
311 __nr_remove_neigh(__neigh)
312
313static void nr_remove_neigh(struct nr_neigh *nr_neigh)
314{
315 spin_lock_bh(&nr_neigh_list_lock);
316 __nr_remove_neigh(nr_neigh);
317 spin_unlock_bh(&nr_neigh_list_lock);
318}
319
320/*
321 * "Delete" a node. Strictly speaking remove a route to a node. The node
322 * is only deleted if no routes are left to it.
323 */
324static int nr_del_node(ax25_address *callsign, ax25_address *neighbour, struct net_device *dev)
325{
326 struct nr_node *nr_node;
327 struct nr_neigh *nr_neigh;
328 int i;
329
330 nr_node = nr_node_get(callsign);
331
332 if (nr_node == NULL)
333 return -EINVAL;
334
335 nr_neigh = nr_neigh_get_dev(neighbour, dev);
336
337 if (nr_neigh == NULL) {
338 nr_node_put(nr_node);
339 return -EINVAL;
340 }
341
342 nr_node_lock(nr_node);
343 for (i = 0; i < nr_node->count; i++) {
344 if (nr_node->routes[i].neighbour == nr_neigh) {
345 nr_neigh->count--;
346 nr_neigh_put(nr_neigh);
347
348 if (nr_neigh->count == 0 && !nr_neigh->locked)
349 nr_remove_neigh(nr_neigh);
350 nr_neigh_put(nr_neigh);
351
352 nr_node->count--;
353
354 if (nr_node->count == 0) {
355 nr_remove_node(nr_node);
356 } else {
357 switch (i) {
358 case 0:
359 nr_node->routes[0] = nr_node->routes[1];
360 fallthrough;
361 case 1:
362 nr_node->routes[1] = nr_node->routes[2];
363 fallthrough;
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 break;
488 case 2:
489 break;
490 }
491 break;
492
493 default:
494 s->routes[i].obs_count--;
495 break;
496
497 }
498 }
499
500 if (s->count <= 0)
501 nr_remove_node_locked(s);
502 nr_node_unlock(s);
503 }
504 spin_unlock_bh(&nr_node_list_lock);
505
506 return 0;
507}
508
509/*
510 * A device has been removed. Remove its routes and neighbours.
511 */
512void nr_rt_device_down(struct net_device *dev)
513{
514 struct nr_neigh *s;
515 struct hlist_node *nodet, *node2t;
516 struct nr_node *t;
517 int i;
518
519 spin_lock_bh(&nr_neigh_list_lock);
520 nr_neigh_for_each_safe(s, nodet, &nr_neigh_list) {
521 if (s->dev == dev) {
522 spin_lock_bh(&nr_node_list_lock);
523 nr_node_for_each_safe(t, node2t, &nr_node_list) {
524 nr_node_lock(t);
525 for (i = 0; i < t->count; i++) {
526 if (t->routes[i].neighbour == s) {
527 t->count--;
528
529 switch (i) {
530 case 0:
531 t->routes[0] = t->routes[1];
532 fallthrough;
533 case 1:
534 t->routes[1] = t->routes[2];
535 break;
536 case 2:
537 break;
538 }
539 }
540 }
541
542 if (t->count <= 0)
543 nr_remove_node_locked(t);
544 nr_node_unlock(t);
545 }
546 spin_unlock_bh(&nr_node_list_lock);
547
548 nr_remove_neigh_locked(s);
549 }
550 }
551 spin_unlock_bh(&nr_neigh_list_lock);
552}
553
554/*
555 * Check that the device given is a valid AX.25 interface that is "up".
556 * Or a valid ethernet interface with an AX.25 callsign binding.
557 */
558static struct net_device *nr_ax25_dev_get(char *devname)
559{
560 struct net_device *dev;
561
562 if ((dev = dev_get_by_name(&init_net, devname)) == NULL)
563 return NULL;
564
565 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_AX25)
566 return dev;
567
568 dev_put(dev);
569 return NULL;
570}
571
572/*
573 * Find the first active NET/ROM device, usually "nr0".
574 */
575struct net_device *nr_dev_first(void)
576{
577 struct net_device *dev, *first = NULL;
578
579 rcu_read_lock();
580 for_each_netdev_rcu(&init_net, dev) {
581 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM)
582 if (first == NULL || strncmp(dev->name, first->name, 3) < 0)
583 first = dev;
584 }
585 if (first)
586 dev_hold(first);
587 rcu_read_unlock();
588
589 return first;
590}
591
592/*
593 * Find the NET/ROM device for the given callsign.
594 */
595struct net_device *nr_dev_get(ax25_address *addr)
596{
597 struct net_device *dev;
598
599 rcu_read_lock();
600 for_each_netdev_rcu(&init_net, dev) {
601 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM &&
602 ax25cmp(addr, (ax25_address *)dev->dev_addr) == 0) {
603 dev_hold(dev);
604 goto out;
605 }
606 }
607 dev = NULL;
608out:
609 rcu_read_unlock();
610 return dev;
611}
612
613static ax25_digi *nr_call_to_digi(ax25_digi *digi, int ndigis,
614 ax25_address *digipeaters)
615{
616 int i;
617
618 if (ndigis == 0)
619 return NULL;
620
621 for (i = 0; i < ndigis; i++) {
622 digi->calls[i] = digipeaters[i];
623 digi->repeated[i] = 0;
624 }
625
626 digi->ndigi = ndigis;
627 digi->lastrepeat = -1;
628
629 return digi;
630}
631
632/*
633 * Handle the ioctls that control the routing functions.
634 */
635int nr_rt_ioctl(unsigned int cmd, void __user *arg)
636{
637 struct nr_route_struct nr_route;
638 struct net_device *dev;
639 ax25_digi digi;
640 int ret;
641
642 switch (cmd) {
643 case SIOCADDRT:
644 if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct)))
645 return -EFAULT;
646 if (nr_route.ndigis > AX25_MAX_DIGIS)
647 return -EINVAL;
648 if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL)
649 return -EINVAL;
650 switch (nr_route.type) {
651 case NETROM_NODE:
652 if (strnlen(nr_route.mnemonic, 7) == 7) {
653 ret = -EINVAL;
654 break;
655 }
656
657 ret = nr_add_node(&nr_route.callsign,
658 nr_route.mnemonic,
659 &nr_route.neighbour,
660 nr_call_to_digi(&digi, nr_route.ndigis,
661 nr_route.digipeaters),
662 dev, nr_route.quality,
663 nr_route.obs_count);
664 break;
665 case NETROM_NEIGH:
666 ret = nr_add_neigh(&nr_route.callsign,
667 nr_call_to_digi(&digi, nr_route.ndigis,
668 nr_route.digipeaters),
669 dev, nr_route.quality);
670 break;
671 default:
672 ret = -EINVAL;
673 }
674 dev_put(dev);
675 return ret;
676
677 case SIOCDELRT:
678 if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct)))
679 return -EFAULT;
680 if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL)
681 return -EINVAL;
682 switch (nr_route.type) {
683 case NETROM_NODE:
684 ret = nr_del_node(&nr_route.callsign,
685 &nr_route.neighbour, dev);
686 break;
687 case NETROM_NEIGH:
688 ret = nr_del_neigh(&nr_route.callsign,
689 dev, nr_route.quality);
690 break;
691 default:
692 ret = -EINVAL;
693 }
694 dev_put(dev);
695 return ret;
696
697 case SIOCNRDECOBS:
698 return nr_dec_obs();
699
700 default:
701 return -EINVAL;
702 }
703
704 return 0;
705}
706
707/*
708 * A level 2 link has timed out, therefore it appears to be a poor link,
709 * then don't use that neighbour until it is reset.
710 */
711void nr_link_failed(ax25_cb *ax25, int reason)
712{
713 struct nr_neigh *s, *nr_neigh = NULL;
714 struct nr_node *nr_node = NULL;
715
716 spin_lock_bh(&nr_neigh_list_lock);
717 nr_neigh_for_each(s, &nr_neigh_list) {
718 if (s->ax25 == ax25) {
719 nr_neigh_hold(s);
720 nr_neigh = s;
721 break;
722 }
723 }
724 spin_unlock_bh(&nr_neigh_list_lock);
725
726 if (nr_neigh == NULL)
727 return;
728
729 nr_neigh->ax25 = NULL;
730 ax25_cb_put(ax25);
731
732 if (++nr_neigh->failed < sysctl_netrom_link_fails_count) {
733 nr_neigh_put(nr_neigh);
734 return;
735 }
736 spin_lock_bh(&nr_node_list_lock);
737 nr_node_for_each(nr_node, &nr_node_list) {
738 nr_node_lock(nr_node);
739 if (nr_node->which < nr_node->count &&
740 nr_node->routes[nr_node->which].neighbour == nr_neigh)
741 nr_node->which++;
742 nr_node_unlock(nr_node);
743 }
744 spin_unlock_bh(&nr_node_list_lock);
745 nr_neigh_put(nr_neigh);
746}
747
748/*
749 * Route a frame to an appropriate AX.25 connection. A NULL ax25_cb
750 * indicates an internally generated frame.
751 */
752int nr_route_frame(struct sk_buff *skb, ax25_cb *ax25)
753{
754 ax25_address *nr_src, *nr_dest;
755 struct nr_neigh *nr_neigh;
756 struct nr_node *nr_node;
757 struct net_device *dev;
758 unsigned char *dptr;
759 ax25_cb *ax25s;
760 int ret;
761 struct sk_buff *skbn;
762
763
764 nr_src = (ax25_address *)(skb->data + 0);
765 nr_dest = (ax25_address *)(skb->data + 7);
766
767 if (ax25 != NULL) {
768 ret = nr_add_node(nr_src, "", &ax25->dest_addr, ax25->digipeat,
769 ax25->ax25_dev->dev, 0,
770 sysctl_netrom_obsolescence_count_initialiser);
771 if (ret)
772 return ret;
773 }
774
775 if ((dev = nr_dev_get(nr_dest)) != NULL) { /* Its for me */
776 if (ax25 == NULL) /* Its from me */
777 ret = nr_loopback_queue(skb);
778 else
779 ret = nr_rx_frame(skb, dev);
780 dev_put(dev);
781 return ret;
782 }
783
784 if (!sysctl_netrom_routing_control && ax25 != NULL)
785 return 0;
786
787 /* Its Time-To-Live has expired */
788 if (skb->data[14] == 1) {
789 return 0;
790 }
791
792 nr_node = nr_node_get(nr_dest);
793 if (nr_node == NULL)
794 return 0;
795 nr_node_lock(nr_node);
796
797 if (nr_node->which >= nr_node->count) {
798 nr_node_unlock(nr_node);
799 nr_node_put(nr_node);
800 return 0;
801 }
802
803 nr_neigh = nr_node->routes[nr_node->which].neighbour;
804
805 if ((dev = nr_dev_first()) == NULL) {
806 nr_node_unlock(nr_node);
807 nr_node_put(nr_node);
808 return 0;
809 }
810
811 /* We are going to change the netrom headers so we should get our
812 own skb, we also did not know until now how much header space
813 we had to reserve... - RXQ */
814 if ((skbn=skb_copy_expand(skb, dev->hard_header_len, 0, GFP_ATOMIC)) == NULL) {
815 nr_node_unlock(nr_node);
816 nr_node_put(nr_node);
817 dev_put(dev);
818 return 0;
819 }
820 kfree_skb(skb);
821 skb=skbn;
822 skb->data[14]--;
823
824 dptr = skb_push(skb, 1);
825 *dptr = AX25_P_NETROM;
826
827 ax25s = nr_neigh->ax25;
828 nr_neigh->ax25 = ax25_send_frame(skb, 256,
829 (ax25_address *)dev->dev_addr,
830 &nr_neigh->callsign,
831 nr_neigh->digipeat, nr_neigh->dev);
832 if (ax25s)
833 ax25_cb_put(ax25s);
834
835 dev_put(dev);
836 ret = (nr_neigh->ax25 != NULL);
837 nr_node_unlock(nr_node);
838 nr_node_put(nr_node);
839
840 return ret;
841}
842
843#ifdef CONFIG_PROC_FS
844
845static void *nr_node_start(struct seq_file *seq, loff_t *pos)
846 __acquires(&nr_node_list_lock)
847{
848 spin_lock_bh(&nr_node_list_lock);
849 return seq_hlist_start_head(&nr_node_list, *pos);
850}
851
852static void *nr_node_next(struct seq_file *seq, void *v, loff_t *pos)
853{
854 return seq_hlist_next(v, &nr_node_list, pos);
855}
856
857static void nr_node_stop(struct seq_file *seq, void *v)
858 __releases(&nr_node_list_lock)
859{
860 spin_unlock_bh(&nr_node_list_lock);
861}
862
863static int nr_node_show(struct seq_file *seq, void *v)
864{
865 char buf[11];
866 int i;
867
868 if (v == SEQ_START_TOKEN)
869 seq_puts(seq,
870 "callsign mnemonic w n qual obs neigh qual obs neigh qual obs neigh\n");
871 else {
872 struct nr_node *nr_node = hlist_entry(v, struct nr_node,
873 node_node);
874
875 nr_node_lock(nr_node);
876 seq_printf(seq, "%-9s %-7s %d %d",
877 ax2asc(buf, &nr_node->callsign),
878 (nr_node->mnemonic[0] == '\0') ? "*" : nr_node->mnemonic,
879 nr_node->which + 1,
880 nr_node->count);
881
882 for (i = 0; i < nr_node->count; i++) {
883 seq_printf(seq, " %3d %d %05d",
884 nr_node->routes[i].quality,
885 nr_node->routes[i].obs_count,
886 nr_node->routes[i].neighbour->number);
887 }
888 nr_node_unlock(nr_node);
889
890 seq_puts(seq, "\n");
891 }
892 return 0;
893}
894
895const struct seq_operations nr_node_seqops = {
896 .start = nr_node_start,
897 .next = nr_node_next,
898 .stop = nr_node_stop,
899 .show = nr_node_show,
900};
901
902static void *nr_neigh_start(struct seq_file *seq, loff_t *pos)
903 __acquires(&nr_neigh_list_lock)
904{
905 spin_lock_bh(&nr_neigh_list_lock);
906 return seq_hlist_start_head(&nr_neigh_list, *pos);
907}
908
909static void *nr_neigh_next(struct seq_file *seq, void *v, loff_t *pos)
910{
911 return seq_hlist_next(v, &nr_neigh_list, pos);
912}
913
914static void nr_neigh_stop(struct seq_file *seq, void *v)
915 __releases(&nr_neigh_list_lock)
916{
917 spin_unlock_bh(&nr_neigh_list_lock);
918}
919
920static int nr_neigh_show(struct seq_file *seq, void *v)
921{
922 char buf[11];
923 int i;
924
925 if (v == SEQ_START_TOKEN)
926 seq_puts(seq, "addr callsign dev qual lock count failed digipeaters\n");
927 else {
928 struct nr_neigh *nr_neigh;
929
930 nr_neigh = hlist_entry(v, struct nr_neigh, neigh_node);
931 seq_printf(seq, "%05d %-9s %-4s %3d %d %3d %3d",
932 nr_neigh->number,
933 ax2asc(buf, &nr_neigh->callsign),
934 nr_neigh->dev ? nr_neigh->dev->name : "???",
935 nr_neigh->quality,
936 nr_neigh->locked,
937 nr_neigh->count,
938 nr_neigh->failed);
939
940 if (nr_neigh->digipeat != NULL) {
941 for (i = 0; i < nr_neigh->digipeat->ndigi; i++)
942 seq_printf(seq, " %s",
943 ax2asc(buf, &nr_neigh->digipeat->calls[i]));
944 }
945
946 seq_puts(seq, "\n");
947 }
948 return 0;
949}
950
951const struct seq_operations nr_neigh_seqops = {
952 .start = nr_neigh_start,
953 .next = nr_neigh_next,
954 .stop = nr_neigh_stop,
955 .show = nr_neigh_show,
956};
957#endif
958
959/*
960 * Free all memory associated with the nodes and routes lists.
961 */
962void nr_rt_free(void)
963{
964 struct nr_neigh *s = NULL;
965 struct nr_node *t = NULL;
966 struct hlist_node *nodet;
967
968 spin_lock_bh(&nr_neigh_list_lock);
969 spin_lock_bh(&nr_node_list_lock);
970 nr_node_for_each_safe(t, nodet, &nr_node_list) {
971 nr_node_lock(t);
972 nr_remove_node_locked(t);
973 nr_node_unlock(t);
974 }
975 nr_neigh_for_each_safe(s, nodet, &nr_neigh_list) {
976 while(s->count) {
977 s->count--;
978 nr_neigh_put(s);
979 }
980 nr_remove_neigh_locked(s);
981 }
982 spin_unlock_bh(&nr_node_list_lock);
983 spin_unlock_bh(&nr_neigh_list_lock);
984}
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 <asm/system.h>
30#include <linux/fcntl.h>
31#include <linux/termios.h> /* For TIOCINQ/OUTQ */
32#include <linux/mm.h>
33#include <linux/interrupt.h>
34#include <linux/notifier.h>
35#include <linux/netfilter.h>
36#include <linux/init.h>
37#include <linux/spinlock.h>
38#include <net/netrom.h>
39#include <linux/seq_file.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 ((dev = nr_ax25_dev_get(nr_route.device)) == NULL)
673 return -EINVAL;
674 if (nr_route.ndigis < 0 || nr_route.ndigis > AX25_MAX_DIGIS) {
675 dev_put(dev);
676 return -EINVAL;
677 }
678 switch (nr_route.type) {
679 case NETROM_NODE:
680 ret = nr_add_node(&nr_route.callsign,
681 nr_route.mnemonic,
682 &nr_route.neighbour,
683 nr_call_to_digi(&digi, nr_route.ndigis,
684 nr_route.digipeaters),
685 dev, nr_route.quality,
686 nr_route.obs_count);
687 break;
688 case NETROM_NEIGH:
689 ret = nr_add_neigh(&nr_route.callsign,
690 nr_call_to_digi(&digi, nr_route.ndigis,
691 nr_route.digipeaters),
692 dev, nr_route.quality);
693 break;
694 default:
695 ret = -EINVAL;
696 }
697 dev_put(dev);
698 return ret;
699
700 case SIOCDELRT:
701 if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct)))
702 return -EFAULT;
703 if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL)
704 return -EINVAL;
705 switch (nr_route.type) {
706 case NETROM_NODE:
707 ret = nr_del_node(&nr_route.callsign,
708 &nr_route.neighbour, dev);
709 break;
710 case NETROM_NEIGH:
711 ret = nr_del_neigh(&nr_route.callsign,
712 dev, nr_route.quality);
713 break;
714 default:
715 ret = -EINVAL;
716 }
717 dev_put(dev);
718 return ret;
719
720 case SIOCNRDECOBS:
721 return nr_dec_obs();
722
723 default:
724 return -EINVAL;
725 }
726
727 return 0;
728}
729
730/*
731 * A level 2 link has timed out, therefore it appears to be a poor link,
732 * then don't use that neighbour until it is reset.
733 */
734void nr_link_failed(ax25_cb *ax25, int reason)
735{
736 struct nr_neigh *s, *nr_neigh = NULL;
737 struct hlist_node *node;
738 struct nr_node *nr_node = NULL;
739
740 spin_lock_bh(&nr_neigh_list_lock);
741 nr_neigh_for_each(s, node, &nr_neigh_list) {
742 if (s->ax25 == ax25) {
743 nr_neigh_hold(s);
744 nr_neigh = s;
745 break;
746 }
747 }
748 spin_unlock_bh(&nr_neigh_list_lock);
749
750 if (nr_neigh == NULL)
751 return;
752
753 nr_neigh->ax25 = NULL;
754 ax25_cb_put(ax25);
755
756 if (++nr_neigh->failed < sysctl_netrom_link_fails_count) {
757 nr_neigh_put(nr_neigh);
758 return;
759 }
760 spin_lock_bh(&nr_node_list_lock);
761 nr_node_for_each(nr_node, node, &nr_node_list) {
762 nr_node_lock(nr_node);
763 if (nr_node->which < nr_node->count &&
764 nr_node->routes[nr_node->which].neighbour == nr_neigh)
765 nr_node->which++;
766 nr_node_unlock(nr_node);
767 }
768 spin_unlock_bh(&nr_node_list_lock);
769 nr_neigh_put(nr_neigh);
770}
771
772/*
773 * Route a frame to an appropriate AX.25 connection. A NULL ax25_cb
774 * indicates an internally generated frame.
775 */
776int nr_route_frame(struct sk_buff *skb, ax25_cb *ax25)
777{
778 ax25_address *nr_src, *nr_dest;
779 struct nr_neigh *nr_neigh;
780 struct nr_node *nr_node;
781 struct net_device *dev;
782 unsigned char *dptr;
783 ax25_cb *ax25s;
784 int ret;
785 struct sk_buff *skbn;
786
787
788 nr_src = (ax25_address *)(skb->data + 0);
789 nr_dest = (ax25_address *)(skb->data + 7);
790
791 if (ax25 != NULL) {
792 ret = nr_add_node(nr_src, "", &ax25->dest_addr, ax25->digipeat,
793 ax25->ax25_dev->dev, 0,
794 sysctl_netrom_obsolescence_count_initialiser);
795 if (ret)
796 return ret;
797 }
798
799 if ((dev = nr_dev_get(nr_dest)) != NULL) { /* Its for me */
800 if (ax25 == NULL) /* Its from me */
801 ret = nr_loopback_queue(skb);
802 else
803 ret = nr_rx_frame(skb, dev);
804 dev_put(dev);
805 return ret;
806 }
807
808 if (!sysctl_netrom_routing_control && ax25 != NULL)
809 return 0;
810
811 /* Its Time-To-Live has expired */
812 if (skb->data[14] == 1) {
813 return 0;
814 }
815
816 nr_node = nr_node_get(nr_dest);
817 if (nr_node == NULL)
818 return 0;
819 nr_node_lock(nr_node);
820
821 if (nr_node->which >= nr_node->count) {
822 nr_node_unlock(nr_node);
823 nr_node_put(nr_node);
824 return 0;
825 }
826
827 nr_neigh = nr_node->routes[nr_node->which].neighbour;
828
829 if ((dev = nr_dev_first()) == NULL) {
830 nr_node_unlock(nr_node);
831 nr_node_put(nr_node);
832 return 0;
833 }
834
835 /* We are going to change the netrom headers so we should get our
836 own skb, we also did not know until now how much header space
837 we had to reserve... - RXQ */
838 if ((skbn=skb_copy_expand(skb, dev->hard_header_len, 0, GFP_ATOMIC)) == NULL) {
839 nr_node_unlock(nr_node);
840 nr_node_put(nr_node);
841 dev_put(dev);
842 return 0;
843 }
844 kfree_skb(skb);
845 skb=skbn;
846 skb->data[14]--;
847
848 dptr = skb_push(skb, 1);
849 *dptr = AX25_P_NETROM;
850
851 ax25s = nr_neigh->ax25;
852 nr_neigh->ax25 = ax25_send_frame(skb, 256,
853 (ax25_address *)dev->dev_addr,
854 &nr_neigh->callsign,
855 nr_neigh->digipeat, nr_neigh->dev);
856 if (ax25s)
857 ax25_cb_put(ax25s);
858
859 dev_put(dev);
860 ret = (nr_neigh->ax25 != NULL);
861 nr_node_unlock(nr_node);
862 nr_node_put(nr_node);
863
864 return ret;
865}
866
867#ifdef CONFIG_PROC_FS
868
869static void *nr_node_start(struct seq_file *seq, loff_t *pos)
870{
871 spin_lock_bh(&nr_node_list_lock);
872 return seq_hlist_start_head(&nr_node_list, *pos);
873}
874
875static void *nr_node_next(struct seq_file *seq, void *v, loff_t *pos)
876{
877 return seq_hlist_next(v, &nr_node_list, pos);
878}
879
880static void nr_node_stop(struct seq_file *seq, void *v)
881{
882 spin_unlock_bh(&nr_node_list_lock);
883}
884
885static int nr_node_show(struct seq_file *seq, void *v)
886{
887 char buf[11];
888 int i;
889
890 if (v == SEQ_START_TOKEN)
891 seq_puts(seq,
892 "callsign mnemonic w n qual obs neigh qual obs neigh qual obs neigh\n");
893 else {
894 struct nr_node *nr_node = hlist_entry(v, struct nr_node,
895 node_node);
896
897 nr_node_lock(nr_node);
898 seq_printf(seq, "%-9s %-7s %d %d",
899 ax2asc(buf, &nr_node->callsign),
900 (nr_node->mnemonic[0] == '\0') ? "*" : nr_node->mnemonic,
901 nr_node->which + 1,
902 nr_node->count);
903
904 for (i = 0; i < nr_node->count; i++) {
905 seq_printf(seq, " %3d %d %05d",
906 nr_node->routes[i].quality,
907 nr_node->routes[i].obs_count,
908 nr_node->routes[i].neighbour->number);
909 }
910 nr_node_unlock(nr_node);
911
912 seq_puts(seq, "\n");
913 }
914 return 0;
915}
916
917static const struct seq_operations nr_node_seqops = {
918 .start = nr_node_start,
919 .next = nr_node_next,
920 .stop = nr_node_stop,
921 .show = nr_node_show,
922};
923
924static int nr_node_info_open(struct inode *inode, struct file *file)
925{
926 return seq_open(file, &nr_node_seqops);
927}
928
929const struct file_operations nr_nodes_fops = {
930 .owner = THIS_MODULE,
931 .open = nr_node_info_open,
932 .read = seq_read,
933 .llseek = seq_lseek,
934 .release = seq_release,
935};
936
937static void *nr_neigh_start(struct seq_file *seq, loff_t *pos)
938{
939 spin_lock_bh(&nr_neigh_list_lock);
940 return seq_hlist_start_head(&nr_neigh_list, *pos);
941}
942
943static void *nr_neigh_next(struct seq_file *seq, void *v, loff_t *pos)
944{
945 return seq_hlist_next(v, &nr_neigh_list, pos);
946}
947
948static void nr_neigh_stop(struct seq_file *seq, void *v)
949{
950 spin_unlock_bh(&nr_neigh_list_lock);
951}
952
953static int nr_neigh_show(struct seq_file *seq, void *v)
954{
955 char buf[11];
956 int i;
957
958 if (v == SEQ_START_TOKEN)
959 seq_puts(seq, "addr callsign dev qual lock count failed digipeaters\n");
960 else {
961 struct nr_neigh *nr_neigh;
962
963 nr_neigh = hlist_entry(v, struct nr_neigh, neigh_node);
964 seq_printf(seq, "%05d %-9s %-4s %3d %d %3d %3d",
965 nr_neigh->number,
966 ax2asc(buf, &nr_neigh->callsign),
967 nr_neigh->dev ? nr_neigh->dev->name : "???",
968 nr_neigh->quality,
969 nr_neigh->locked,
970 nr_neigh->count,
971 nr_neigh->failed);
972
973 if (nr_neigh->digipeat != NULL) {
974 for (i = 0; i < nr_neigh->digipeat->ndigi; i++)
975 seq_printf(seq, " %s",
976 ax2asc(buf, &nr_neigh->digipeat->calls[i]));
977 }
978
979 seq_puts(seq, "\n");
980 }
981 return 0;
982}
983
984static const struct seq_operations nr_neigh_seqops = {
985 .start = nr_neigh_start,
986 .next = nr_neigh_next,
987 .stop = nr_neigh_stop,
988 .show = nr_neigh_show,
989};
990
991static int nr_neigh_info_open(struct inode *inode, struct file *file)
992{
993 return seq_open(file, &nr_neigh_seqops);
994}
995
996const struct file_operations nr_neigh_fops = {
997 .owner = THIS_MODULE,
998 .open = nr_neigh_info_open,
999 .read = seq_read,
1000 .llseek = seq_lseek,
1001 .release = seq_release,
1002};
1003
1004#endif
1005
1006/*
1007 * Free all memory associated with the nodes and routes lists.
1008 */
1009void __exit nr_rt_free(void)
1010{
1011 struct nr_neigh *s = NULL;
1012 struct nr_node *t = NULL;
1013 struct hlist_node *node, *nodet;
1014
1015 spin_lock_bh(&nr_neigh_list_lock);
1016 spin_lock_bh(&nr_node_list_lock);
1017 nr_node_for_each_safe(t, node, nodet, &nr_node_list) {
1018 nr_node_lock(t);
1019 nr_remove_node_locked(t);
1020 nr_node_unlock(t);
1021 }
1022 nr_neigh_for_each_safe(s, node, nodet, &nr_neigh_list) {
1023 while(s->count) {
1024 s->count--;
1025 nr_neigh_put(s);
1026 }
1027 nr_remove_neigh_locked(s);
1028 }
1029 spin_unlock_bh(&nr_node_list_lock);
1030 spin_unlock_bh(&nr_neigh_list_lock);
1031}