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