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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 case 1:
270 break;
271 }
272
273 for (i = 0; i < nr_node->count; i++) {
274 if (nr_node->routes[i].neighbour == nr_neigh) {
275 if (i < nr_node->which)
276 nr_node->which = i;
277 break;
278 }
279 }
280
281 nr_neigh_put(nr_neigh);
282 nr_node_unlock(nr_node);
283 nr_node_put(nr_node);
284 return 0;
285}
286
287static inline void __nr_remove_node(struct nr_node *nr_node)
288{
289 hlist_del_init(&nr_node->node_node);
290 nr_node_put(nr_node);
291}
292
293#define nr_remove_node_locked(__node) \
294 __nr_remove_node(__node)
295
296static void nr_remove_node(struct nr_node *nr_node)
297{
298 spin_lock_bh(&nr_node_list_lock);
299 __nr_remove_node(nr_node);
300 spin_unlock_bh(&nr_node_list_lock);
301}
302
303static inline void __nr_remove_neigh(struct nr_neigh *nr_neigh)
304{
305 hlist_del_init(&nr_neigh->neigh_node);
306 nr_neigh_put(nr_neigh);
307}
308
309#define nr_remove_neigh_locked(__neigh) \
310 __nr_remove_neigh(__neigh)
311
312static void nr_remove_neigh(struct nr_neigh *nr_neigh)
313{
314 spin_lock_bh(&nr_neigh_list_lock);
315 __nr_remove_neigh(nr_neigh);
316 spin_unlock_bh(&nr_neigh_list_lock);
317}
318
319/*
320 * "Delete" a node. Strictly speaking remove a route to a node. The node
321 * is only deleted if no routes are left to it.
322 */
323static int nr_del_node(ax25_address *callsign, ax25_address *neighbour, struct net_device *dev)
324{
325 struct nr_node *nr_node;
326 struct nr_neigh *nr_neigh;
327 int i;
328
329 nr_node = nr_node_get(callsign);
330
331 if (nr_node == NULL)
332 return -EINVAL;
333
334 nr_neigh = nr_neigh_get_dev(neighbour, dev);
335
336 if (nr_neigh == NULL) {
337 nr_node_put(nr_node);
338 return -EINVAL;
339 }
340
341 nr_node_lock(nr_node);
342 for (i = 0; i < nr_node->count; i++) {
343 if (nr_node->routes[i].neighbour == nr_neigh) {
344 nr_neigh->count--;
345 nr_neigh_put(nr_neigh);
346
347 if (nr_neigh->count == 0 && !nr_neigh->locked)
348 nr_remove_neigh(nr_neigh);
349 nr_neigh_put(nr_neigh);
350
351 nr_node->count--;
352
353 if (nr_node->count == 0) {
354 nr_remove_node(nr_node);
355 } else {
356 switch (i) {
357 case 0:
358 nr_node->routes[0] = nr_node->routes[1];
359 fallthrough;
360 case 1:
361 nr_node->routes[1] = nr_node->routes[2];
362 case 2:
363 break;
364 }
365 nr_node_put(nr_node);
366 }
367 nr_node_unlock(nr_node);
368
369 return 0;
370 }
371 }
372 nr_neigh_put(nr_neigh);
373 nr_node_unlock(nr_node);
374 nr_node_put(nr_node);
375
376 return -EINVAL;
377}
378
379/*
380 * Lock a neighbour with a quality.
381 */
382static int __must_check nr_add_neigh(ax25_address *callsign,
383 ax25_digi *ax25_digi, struct net_device *dev, unsigned int quality)
384{
385 struct nr_neigh *nr_neigh;
386
387 nr_neigh = nr_neigh_get_dev(callsign, dev);
388 if (nr_neigh) {
389 nr_neigh->quality = quality;
390 nr_neigh->locked = 1;
391 nr_neigh_put(nr_neigh);
392 return 0;
393 }
394
395 if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL)
396 return -ENOMEM;
397
398 nr_neigh->callsign = *callsign;
399 nr_neigh->digipeat = NULL;
400 nr_neigh->ax25 = NULL;
401 nr_neigh->dev = dev;
402 nr_neigh->quality = quality;
403 nr_neigh->locked = 1;
404 nr_neigh->count = 0;
405 nr_neigh->number = nr_neigh_no++;
406 nr_neigh->failed = 0;
407 refcount_set(&nr_neigh->refcount, 1);
408
409 if (ax25_digi != NULL && ax25_digi->ndigi > 0) {
410 nr_neigh->digipeat = kmemdup(ax25_digi, sizeof(*ax25_digi),
411 GFP_KERNEL);
412 if (nr_neigh->digipeat == NULL) {
413 kfree(nr_neigh);
414 return -ENOMEM;
415 }
416 }
417
418 spin_lock_bh(&nr_neigh_list_lock);
419 hlist_add_head(&nr_neigh->neigh_node, &nr_neigh_list);
420 /* refcount is initialized at 1 */
421 spin_unlock_bh(&nr_neigh_list_lock);
422
423 return 0;
424}
425
426/*
427 * "Delete" a neighbour. The neighbour is only removed if the number
428 * of nodes that may use it is zero.
429 */
430static int nr_del_neigh(ax25_address *callsign, struct net_device *dev, unsigned int quality)
431{
432 struct nr_neigh *nr_neigh;
433
434 nr_neigh = nr_neigh_get_dev(callsign, dev);
435
436 if (nr_neigh == NULL) return -EINVAL;
437
438 nr_neigh->quality = quality;
439 nr_neigh->locked = 0;
440
441 if (nr_neigh->count == 0)
442 nr_remove_neigh(nr_neigh);
443 nr_neigh_put(nr_neigh);
444
445 return 0;
446}
447
448/*
449 * Decrement the obsolescence count by one. If a route is reduced to a
450 * count of zero, remove it. Also remove any unlocked neighbours with
451 * zero nodes routing via it.
452 */
453static int nr_dec_obs(void)
454{
455 struct nr_neigh *nr_neigh;
456 struct nr_node *s;
457 struct hlist_node *nodet;
458 int i;
459
460 spin_lock_bh(&nr_node_list_lock);
461 nr_node_for_each_safe(s, nodet, &nr_node_list) {
462 nr_node_lock(s);
463 for (i = 0; i < s->count; i++) {
464 switch (s->routes[i].obs_count) {
465 case 0: /* A locked entry */
466 break;
467
468 case 1: /* From 1 -> 0 */
469 nr_neigh = s->routes[i].neighbour;
470
471 nr_neigh->count--;
472 nr_neigh_put(nr_neigh);
473
474 if (nr_neigh->count == 0 && !nr_neigh->locked)
475 nr_remove_neigh(nr_neigh);
476
477 s->count--;
478
479 switch (i) {
480 case 0:
481 s->routes[0] = s->routes[1];
482 fallthrough;
483 case 1:
484 s->routes[1] = s->routes[2];
485 case 2:
486 break;
487 }
488 break;
489
490 default:
491 s->routes[i].obs_count--;
492 break;
493
494 }
495 }
496
497 if (s->count <= 0)
498 nr_remove_node_locked(s);
499 nr_node_unlock(s);
500 }
501 spin_unlock_bh(&nr_node_list_lock);
502
503 return 0;
504}
505
506/*
507 * A device has been removed. Remove its routes and neighbours.
508 */
509void nr_rt_device_down(struct net_device *dev)
510{
511 struct nr_neigh *s;
512 struct hlist_node *nodet, *node2t;
513 struct nr_node *t;
514 int i;
515
516 spin_lock_bh(&nr_neigh_list_lock);
517 nr_neigh_for_each_safe(s, nodet, &nr_neigh_list) {
518 if (s->dev == dev) {
519 spin_lock_bh(&nr_node_list_lock);
520 nr_node_for_each_safe(t, node2t, &nr_node_list) {
521 nr_node_lock(t);
522 for (i = 0; i < t->count; i++) {
523 if (t->routes[i].neighbour == s) {
524 t->count--;
525
526 switch (i) {
527 case 0:
528 t->routes[0] = t->routes[1];
529 fallthrough;
530 case 1:
531 t->routes[1] = t->routes[2];
532 case 2:
533 break;
534 }
535 }
536 }
537
538 if (t->count <= 0)
539 nr_remove_node_locked(t);
540 nr_node_unlock(t);
541 }
542 spin_unlock_bh(&nr_node_list_lock);
543
544 nr_remove_neigh_locked(s);
545 }
546 }
547 spin_unlock_bh(&nr_neigh_list_lock);
548}
549
550/*
551 * Check that the device given is a valid AX.25 interface that is "up".
552 * Or a valid ethernet interface with an AX.25 callsign binding.
553 */
554static struct net_device *nr_ax25_dev_get(char *devname)
555{
556 struct net_device *dev;
557
558 if ((dev = dev_get_by_name(&init_net, devname)) == NULL)
559 return NULL;
560
561 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_AX25)
562 return dev;
563
564 dev_put(dev);
565 return NULL;
566}
567
568/*
569 * Find the first active NET/ROM device, usually "nr0".
570 */
571struct net_device *nr_dev_first(void)
572{
573 struct net_device *dev, *first = NULL;
574
575 rcu_read_lock();
576 for_each_netdev_rcu(&init_net, dev) {
577 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM)
578 if (first == NULL || strncmp(dev->name, first->name, 3) < 0)
579 first = dev;
580 }
581 if (first)
582 dev_hold(first);
583 rcu_read_unlock();
584
585 return first;
586}
587
588/*
589 * Find the NET/ROM device for the given callsign.
590 */
591struct net_device *nr_dev_get(ax25_address *addr)
592{
593 struct net_device *dev;
594
595 rcu_read_lock();
596 for_each_netdev_rcu(&init_net, dev) {
597 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM &&
598 ax25cmp(addr, (ax25_address *)dev->dev_addr) == 0) {
599 dev_hold(dev);
600 goto out;
601 }
602 }
603 dev = NULL;
604out:
605 rcu_read_unlock();
606 return dev;
607}
608
609static ax25_digi *nr_call_to_digi(ax25_digi *digi, int ndigis,
610 ax25_address *digipeaters)
611{
612 int i;
613
614 if (ndigis == 0)
615 return NULL;
616
617 for (i = 0; i < ndigis; i++) {
618 digi->calls[i] = digipeaters[i];
619 digi->repeated[i] = 0;
620 }
621
622 digi->ndigi = ndigis;
623 digi->lastrepeat = -1;
624
625 return digi;
626}
627
628/*
629 * Handle the ioctls that control the routing functions.
630 */
631int nr_rt_ioctl(unsigned int cmd, void __user *arg)
632{
633 struct nr_route_struct nr_route;
634 struct net_device *dev;
635 ax25_digi digi;
636 int ret;
637
638 switch (cmd) {
639 case SIOCADDRT:
640 if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct)))
641 return -EFAULT;
642 if (nr_route.ndigis > AX25_MAX_DIGIS)
643 return -EINVAL;
644 if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL)
645 return -EINVAL;
646 switch (nr_route.type) {
647 case NETROM_NODE:
648 if (strnlen(nr_route.mnemonic, 7) == 7) {
649 ret = -EINVAL;
650 break;
651 }
652
653 ret = nr_add_node(&nr_route.callsign,
654 nr_route.mnemonic,
655 &nr_route.neighbour,
656 nr_call_to_digi(&digi, nr_route.ndigis,
657 nr_route.digipeaters),
658 dev, nr_route.quality,
659 nr_route.obs_count);
660 break;
661 case NETROM_NEIGH:
662 ret = nr_add_neigh(&nr_route.callsign,
663 nr_call_to_digi(&digi, nr_route.ndigis,
664 nr_route.digipeaters),
665 dev, nr_route.quality);
666 break;
667 default:
668 ret = -EINVAL;
669 }
670 dev_put(dev);
671 return ret;
672
673 case SIOCDELRT:
674 if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct)))
675 return -EFAULT;
676 if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL)
677 return -EINVAL;
678 switch (nr_route.type) {
679 case NETROM_NODE:
680 ret = nr_del_node(&nr_route.callsign,
681 &nr_route.neighbour, dev);
682 break;
683 case NETROM_NEIGH:
684 ret = nr_del_neigh(&nr_route.callsign,
685 dev, nr_route.quality);
686 break;
687 default:
688 ret = -EINVAL;
689 }
690 dev_put(dev);
691 return ret;
692
693 case SIOCNRDECOBS:
694 return nr_dec_obs();
695
696 default:
697 return -EINVAL;
698 }
699
700 return 0;
701}
702
703/*
704 * A level 2 link has timed out, therefore it appears to be a poor link,
705 * then don't use that neighbour until it is reset.
706 */
707void nr_link_failed(ax25_cb *ax25, int reason)
708{
709 struct nr_neigh *s, *nr_neigh = NULL;
710 struct nr_node *nr_node = NULL;
711
712 spin_lock_bh(&nr_neigh_list_lock);
713 nr_neigh_for_each(s, &nr_neigh_list) {
714 if (s->ax25 == ax25) {
715 nr_neigh_hold(s);
716 nr_neigh = s;
717 break;
718 }
719 }
720 spin_unlock_bh(&nr_neigh_list_lock);
721
722 if (nr_neigh == NULL)
723 return;
724
725 nr_neigh->ax25 = NULL;
726 ax25_cb_put(ax25);
727
728 if (++nr_neigh->failed < sysctl_netrom_link_fails_count) {
729 nr_neigh_put(nr_neigh);
730 return;
731 }
732 spin_lock_bh(&nr_node_list_lock);
733 nr_node_for_each(nr_node, &nr_node_list) {
734 nr_node_lock(nr_node);
735 if (nr_node->which < nr_node->count &&
736 nr_node->routes[nr_node->which].neighbour == nr_neigh)
737 nr_node->which++;
738 nr_node_unlock(nr_node);
739 }
740 spin_unlock_bh(&nr_node_list_lock);
741 nr_neigh_put(nr_neigh);
742}
743
744/*
745 * Route a frame to an appropriate AX.25 connection. A NULL ax25_cb
746 * indicates an internally generated frame.
747 */
748int nr_route_frame(struct sk_buff *skb, ax25_cb *ax25)
749{
750 ax25_address *nr_src, *nr_dest;
751 struct nr_neigh *nr_neigh;
752 struct nr_node *nr_node;
753 struct net_device *dev;
754 unsigned char *dptr;
755 ax25_cb *ax25s;
756 int ret;
757 struct sk_buff *skbn;
758
759
760 nr_src = (ax25_address *)(skb->data + 0);
761 nr_dest = (ax25_address *)(skb->data + 7);
762
763 if (ax25 != NULL) {
764 ret = nr_add_node(nr_src, "", &ax25->dest_addr, ax25->digipeat,
765 ax25->ax25_dev->dev, 0,
766 sysctl_netrom_obsolescence_count_initialiser);
767 if (ret)
768 return ret;
769 }
770
771 if ((dev = nr_dev_get(nr_dest)) != NULL) { /* Its for me */
772 if (ax25 == NULL) /* Its from me */
773 ret = nr_loopback_queue(skb);
774 else
775 ret = nr_rx_frame(skb, dev);
776 dev_put(dev);
777 return ret;
778 }
779
780 if (!sysctl_netrom_routing_control && ax25 != NULL)
781 return 0;
782
783 /* Its Time-To-Live has expired */
784 if (skb->data[14] == 1) {
785 return 0;
786 }
787
788 nr_node = nr_node_get(nr_dest);
789 if (nr_node == NULL)
790 return 0;
791 nr_node_lock(nr_node);
792
793 if (nr_node->which >= nr_node->count) {
794 nr_node_unlock(nr_node);
795 nr_node_put(nr_node);
796 return 0;
797 }
798
799 nr_neigh = nr_node->routes[nr_node->which].neighbour;
800
801 if ((dev = nr_dev_first()) == NULL) {
802 nr_node_unlock(nr_node);
803 nr_node_put(nr_node);
804 return 0;
805 }
806
807 /* We are going to change the netrom headers so we should get our
808 own skb, we also did not know until now how much header space
809 we had to reserve... - RXQ */
810 if ((skbn=skb_copy_expand(skb, dev->hard_header_len, 0, GFP_ATOMIC)) == NULL) {
811 nr_node_unlock(nr_node);
812 nr_node_put(nr_node);
813 dev_put(dev);
814 return 0;
815 }
816 kfree_skb(skb);
817 skb=skbn;
818 skb->data[14]--;
819
820 dptr = skb_push(skb, 1);
821 *dptr = AX25_P_NETROM;
822
823 ax25s = nr_neigh->ax25;
824 nr_neigh->ax25 = ax25_send_frame(skb, 256,
825 (ax25_address *)dev->dev_addr,
826 &nr_neigh->callsign,
827 nr_neigh->digipeat, nr_neigh->dev);
828 if (ax25s)
829 ax25_cb_put(ax25s);
830
831 dev_put(dev);
832 ret = (nr_neigh->ax25 != NULL);
833 nr_node_unlock(nr_node);
834 nr_node_put(nr_node);
835
836 return ret;
837}
838
839#ifdef CONFIG_PROC_FS
840
841static void *nr_node_start(struct seq_file *seq, loff_t *pos)
842 __acquires(&nr_node_list_lock)
843{
844 spin_lock_bh(&nr_node_list_lock);
845 return seq_hlist_start_head(&nr_node_list, *pos);
846}
847
848static void *nr_node_next(struct seq_file *seq, void *v, loff_t *pos)
849{
850 return seq_hlist_next(v, &nr_node_list, pos);
851}
852
853static void nr_node_stop(struct seq_file *seq, void *v)
854 __releases(&nr_node_list_lock)
855{
856 spin_unlock_bh(&nr_node_list_lock);
857}
858
859static int nr_node_show(struct seq_file *seq, void *v)
860{
861 char buf[11];
862 int i;
863
864 if (v == SEQ_START_TOKEN)
865 seq_puts(seq,
866 "callsign mnemonic w n qual obs neigh qual obs neigh qual obs neigh\n");
867 else {
868 struct nr_node *nr_node = hlist_entry(v, struct nr_node,
869 node_node);
870
871 nr_node_lock(nr_node);
872 seq_printf(seq, "%-9s %-7s %d %d",
873 ax2asc(buf, &nr_node->callsign),
874 (nr_node->mnemonic[0] == '\0') ? "*" : nr_node->mnemonic,
875 nr_node->which + 1,
876 nr_node->count);
877
878 for (i = 0; i < nr_node->count; i++) {
879 seq_printf(seq, " %3d %d %05d",
880 nr_node->routes[i].quality,
881 nr_node->routes[i].obs_count,
882 nr_node->routes[i].neighbour->number);
883 }
884 nr_node_unlock(nr_node);
885
886 seq_puts(seq, "\n");
887 }
888 return 0;
889}
890
891const struct seq_operations nr_node_seqops = {
892 .start = nr_node_start,
893 .next = nr_node_next,
894 .stop = nr_node_stop,
895 .show = nr_node_show,
896};
897
898static void *nr_neigh_start(struct seq_file *seq, loff_t *pos)
899 __acquires(&nr_neigh_list_lock)
900{
901 spin_lock_bh(&nr_neigh_list_lock);
902 return seq_hlist_start_head(&nr_neigh_list, *pos);
903}
904
905static void *nr_neigh_next(struct seq_file *seq, void *v, loff_t *pos)
906{
907 return seq_hlist_next(v, &nr_neigh_list, pos);
908}
909
910static void nr_neigh_stop(struct seq_file *seq, void *v)
911 __releases(&nr_neigh_list_lock)
912{
913 spin_unlock_bh(&nr_neigh_list_lock);
914}
915
916static int nr_neigh_show(struct seq_file *seq, void *v)
917{
918 char buf[11];
919 int i;
920
921 if (v == SEQ_START_TOKEN)
922 seq_puts(seq, "addr callsign dev qual lock count failed digipeaters\n");
923 else {
924 struct nr_neigh *nr_neigh;
925
926 nr_neigh = hlist_entry(v, struct nr_neigh, neigh_node);
927 seq_printf(seq, "%05d %-9s %-4s %3d %d %3d %3d",
928 nr_neigh->number,
929 ax2asc(buf, &nr_neigh->callsign),
930 nr_neigh->dev ? nr_neigh->dev->name : "???",
931 nr_neigh->quality,
932 nr_neigh->locked,
933 nr_neigh->count,
934 nr_neigh->failed);
935
936 if (nr_neigh->digipeat != NULL) {
937 for (i = 0; i < nr_neigh->digipeat->ndigi; i++)
938 seq_printf(seq, " %s",
939 ax2asc(buf, &nr_neigh->digipeat->calls[i]));
940 }
941
942 seq_puts(seq, "\n");
943 }
944 return 0;
945}
946
947const struct seq_operations nr_neigh_seqops = {
948 .start = nr_neigh_start,
949 .next = nr_neigh_next,
950 .stop = nr_neigh_stop,
951 .show = nr_neigh_show,
952};
953#endif
954
955/*
956 * Free all memory associated with the nodes and routes lists.
957 */
958void nr_rt_free(void)
959{
960 struct nr_neigh *s = NULL;
961 struct nr_node *t = NULL;
962 struct hlist_node *nodet;
963
964 spin_lock_bh(&nr_neigh_list_lock);
965 spin_lock_bh(&nr_node_list_lock);
966 nr_node_for_each_safe(t, nodet, &nr_node_list) {
967 nr_node_lock(t);
968 nr_remove_node_locked(t);
969 nr_node_unlock(t);
970 }
971 nr_neigh_for_each_safe(s, nodet, &nr_neigh_list) {
972 while(s->count) {
973 s->count--;
974 nr_neigh_put(s);
975 }
976 nr_remove_neigh_locked(s);
977 }
978 spin_unlock_bh(&nr_node_list_lock);
979 spin_unlock_bh(&nr_neigh_list_lock);
980}