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