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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *
4 * Copyright Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
5 * Copyright Alan Cox GW4PTS (alan@lxorguk.ukuu.org.uk)
6 * Copyright Tomi Manninen OH2BNS (oh2bns@sral.fi)
7 */
8#include <linux/errno.h>
9#include <linux/types.h>
10#include <linux/socket.h>
11#include <linux/in.h>
12#include <linux/kernel.h>
13#include <linux/timer.h>
14#include <linux/string.h>
15#include <linux/sockios.h>
16#include <linux/net.h>
17#include <linux/slab.h>
18#include <net/ax25.h>
19#include <linux/inet.h>
20#include <linux/netdevice.h>
21#include <net/arp.h>
22#include <linux/if_arp.h>
23#include <linux/skbuff.h>
24#include <net/sock.h>
25#include <linux/uaccess.h>
26#include <linux/fcntl.h>
27#include <linux/termios.h> /* For TIOCINQ/OUTQ */
28#include <linux/mm.h>
29#include <linux/interrupt.h>
30#include <linux/notifier.h>
31#include <linux/init.h>
32#include <linux/spinlock.h>
33#include <net/netrom.h>
34#include <linux/seq_file.h>
35#include <linux/export.h>
36
37static unsigned int nr_neigh_no = 1;
38
39static HLIST_HEAD(nr_node_list);
40static DEFINE_SPINLOCK(nr_node_list_lock);
41static HLIST_HEAD(nr_neigh_list);
42static DEFINE_SPINLOCK(nr_neigh_list_lock);
43
44static struct nr_node *nr_node_get(ax25_address *callsign)
45{
46 struct nr_node *found = NULL;
47 struct nr_node *nr_node;
48
49 spin_lock_bh(&nr_node_list_lock);
50 nr_node_for_each(nr_node, &nr_node_list)
51 if (ax25cmp(callsign, &nr_node->callsign) == 0) {
52 nr_node_hold(nr_node);
53 found = nr_node;
54 break;
55 }
56 spin_unlock_bh(&nr_node_list_lock);
57 return found;
58}
59
60static struct nr_neigh *nr_neigh_get_dev(ax25_address *callsign,
61 struct net_device *dev)
62{
63 struct nr_neigh *found = NULL;
64 struct nr_neigh *nr_neigh;
65
66 spin_lock_bh(&nr_neigh_list_lock);
67 nr_neigh_for_each(nr_neigh, &nr_neigh_list)
68 if (ax25cmp(callsign, &nr_neigh->callsign) == 0 &&
69 nr_neigh->dev == dev) {
70 nr_neigh_hold(nr_neigh);
71 found = nr_neigh;
72 break;
73 }
74 spin_unlock_bh(&nr_neigh_list_lock);
75 return found;
76}
77
78static void nr_remove_neigh(struct nr_neigh *);
79
80/* re-sort the routes in quality order. */
81static void re_sort_routes(struct nr_node *nr_node, int x, int y)
82{
83 if (nr_node->routes[y].quality > nr_node->routes[x].quality) {
84 if (nr_node->which == x)
85 nr_node->which = y;
86 else if (nr_node->which == y)
87 nr_node->which = x;
88
89 swap(nr_node->routes[x], nr_node->routes[y]);
90 }
91}
92
93/*
94 * Add a new route to a node, and in the process add the node and the
95 * neighbour if it is new.
96 */
97static int __must_check nr_add_node(ax25_address *nr, const char *mnemonic,
98 ax25_address *ax25, ax25_digi *ax25_digi, struct net_device *dev,
99 int quality, int obs_count)
100{
101 struct nr_node *nr_node;
102 struct nr_neigh *nr_neigh;
103 int i, found;
104 struct net_device *odev;
105
106 if ((odev=nr_dev_get(nr)) != NULL) { /* Can't add routes to ourself */
107 dev_put(odev);
108 return -EINVAL;
109 }
110
111 nr_node = nr_node_get(nr);
112
113 nr_neigh = nr_neigh_get_dev(ax25, dev);
114
115 /*
116 * The L2 link to a neighbour has failed in the past
117 * and now a frame comes from this neighbour. We assume
118 * it was a temporary trouble with the link and reset the
119 * routes now (and not wait for a node broadcast).
120 */
121 if (nr_neigh != NULL && nr_neigh->failed != 0 && quality == 0) {
122 struct nr_node *nr_nodet;
123
124 spin_lock_bh(&nr_node_list_lock);
125 nr_node_for_each(nr_nodet, &nr_node_list) {
126 nr_node_lock(nr_nodet);
127 for (i = 0; i < nr_nodet->count; i++)
128 if (nr_nodet->routes[i].neighbour == nr_neigh)
129 if (i < nr_nodet->which)
130 nr_nodet->which = i;
131 nr_node_unlock(nr_nodet);
132 }
133 spin_unlock_bh(&nr_node_list_lock);
134 }
135
136 if (nr_neigh != NULL)
137 nr_neigh->failed = 0;
138
139 if (quality == 0 && nr_neigh != NULL && nr_node != NULL) {
140 nr_neigh_put(nr_neigh);
141 nr_node_put(nr_node);
142 return 0;
143 }
144
145 if (nr_neigh == NULL) {
146 if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL) {
147 if (nr_node)
148 nr_node_put(nr_node);
149 return -ENOMEM;
150 }
151
152 nr_neigh->callsign = *ax25;
153 nr_neigh->digipeat = NULL;
154 nr_neigh->ax25 = NULL;
155 nr_neigh->dev = dev;
156 nr_neigh->quality = sysctl_netrom_default_path_quality;
157 nr_neigh->locked = 0;
158 nr_neigh->count = 0;
159 nr_neigh->number = nr_neigh_no++;
160 nr_neigh->failed = 0;
161 refcount_set(&nr_neigh->refcount, 1);
162
163 if (ax25_digi != NULL && ax25_digi->ndigi > 0) {
164 nr_neigh->digipeat = kmemdup(ax25_digi,
165 sizeof(*ax25_digi),
166 GFP_KERNEL);
167 if (nr_neigh->digipeat == NULL) {
168 kfree(nr_neigh);
169 if (nr_node)
170 nr_node_put(nr_node);
171 return -ENOMEM;
172 }
173 }
174
175 spin_lock_bh(&nr_neigh_list_lock);
176 hlist_add_head(&nr_neigh->neigh_node, &nr_neigh_list);
177 nr_neigh_hold(nr_neigh);
178 spin_unlock_bh(&nr_neigh_list_lock);
179 }
180
181 if (quality != 0 && ax25cmp(nr, ax25) == 0 && !nr_neigh->locked)
182 nr_neigh->quality = quality;
183
184 if (nr_node == NULL) {
185 if ((nr_node = kmalloc(sizeof(*nr_node), GFP_ATOMIC)) == NULL) {
186 if (nr_neigh)
187 nr_neigh_put(nr_neigh);
188 return -ENOMEM;
189 }
190
191 nr_node->callsign = *nr;
192 strcpy(nr_node->mnemonic, mnemonic);
193
194 nr_node->which = 0;
195 nr_node->count = 1;
196 refcount_set(&nr_node->refcount, 1);
197 spin_lock_init(&nr_node->node_lock);
198
199 nr_node->routes[0].quality = quality;
200 nr_node->routes[0].obs_count = obs_count;
201 nr_node->routes[0].neighbour = nr_neigh;
202
203 nr_neigh_hold(nr_neigh);
204 nr_neigh->count++;
205
206 spin_lock_bh(&nr_node_list_lock);
207 hlist_add_head(&nr_node->node_node, &nr_node_list);
208 /* refcount initialized at 1 */
209 spin_unlock_bh(&nr_node_list_lock);
210
211 nr_neigh_put(nr_neigh);
212 return 0;
213 }
214 nr_node_lock(nr_node);
215
216 if (quality != 0)
217 strcpy(nr_node->mnemonic, mnemonic);
218
219 for (found = 0, i = 0; i < nr_node->count; i++) {
220 if (nr_node->routes[i].neighbour == nr_neigh) {
221 nr_node->routes[i].quality = quality;
222 nr_node->routes[i].obs_count = obs_count;
223 found = 1;
224 break;
225 }
226 }
227
228 if (!found) {
229 /* We have space at the bottom, slot it in */
230 if (nr_node->count < 3) {
231 nr_node->routes[2] = nr_node->routes[1];
232 nr_node->routes[1] = nr_node->routes[0];
233
234 nr_node->routes[0].quality = quality;
235 nr_node->routes[0].obs_count = obs_count;
236 nr_node->routes[0].neighbour = nr_neigh;
237
238 nr_node->which++;
239 nr_node->count++;
240 nr_neigh_hold(nr_neigh);
241 nr_neigh->count++;
242 } else {
243 /* It must be better than the worst */
244 if (quality > nr_node->routes[2].quality) {
245 nr_node->routes[2].neighbour->count--;
246 nr_neigh_put(nr_node->routes[2].neighbour);
247
248 if (nr_node->routes[2].neighbour->count == 0 && !nr_node->routes[2].neighbour->locked)
249 nr_remove_neigh(nr_node->routes[2].neighbour);
250
251 nr_node->routes[2].quality = quality;
252 nr_node->routes[2].obs_count = obs_count;
253 nr_node->routes[2].neighbour = nr_neigh;
254
255 nr_neigh_hold(nr_neigh);
256 nr_neigh->count++;
257 }
258 }
259 }
260
261 /* Now re-sort the routes in quality order */
262 switch (nr_node->count) {
263 case 3:
264 re_sort_routes(nr_node, 0, 1);
265 re_sort_routes(nr_node, 1, 2);
266 fallthrough;
267 case 2:
268 re_sort_routes(nr_node, 0, 1);
269 break;
270 case 1:
271 break;
272 }
273
274 for (i = 0; i < nr_node->count; i++) {
275 if (nr_node->routes[i].neighbour == nr_neigh) {
276 if (i < nr_node->which)
277 nr_node->which = i;
278 break;
279 }
280 }
281
282 nr_neigh_put(nr_neigh);
283 nr_node_unlock(nr_node);
284 nr_node_put(nr_node);
285 return 0;
286}
287
288static inline void __nr_remove_node(struct nr_node *nr_node)
289{
290 hlist_del_init(&nr_node->node_node);
291 nr_node_put(nr_node);
292}
293
294#define nr_remove_node_locked(__node) \
295 __nr_remove_node(__node)
296
297static void nr_remove_node(struct nr_node *nr_node)
298{
299 spin_lock_bh(&nr_node_list_lock);
300 __nr_remove_node(nr_node);
301 spin_unlock_bh(&nr_node_list_lock);
302}
303
304static inline void __nr_remove_neigh(struct nr_neigh *nr_neigh)
305{
306 hlist_del_init(&nr_neigh->neigh_node);
307 nr_neigh_put(nr_neigh);
308}
309
310#define nr_remove_neigh_locked(__neigh) \
311 __nr_remove_neigh(__neigh)
312
313static void nr_remove_neigh(struct nr_neigh *nr_neigh)
314{
315 spin_lock_bh(&nr_neigh_list_lock);
316 __nr_remove_neigh(nr_neigh);
317 spin_unlock_bh(&nr_neigh_list_lock);
318}
319
320/*
321 * "Delete" a node. Strictly speaking remove a route to a node. The node
322 * is only deleted if no routes are left to it.
323 */
324static int nr_del_node(ax25_address *callsign, ax25_address *neighbour, struct net_device *dev)
325{
326 struct nr_node *nr_node;
327 struct nr_neigh *nr_neigh;
328 int i;
329
330 nr_node = nr_node_get(callsign);
331
332 if (nr_node == NULL)
333 return -EINVAL;
334
335 nr_neigh = nr_neigh_get_dev(neighbour, dev);
336
337 if (nr_neigh == NULL) {
338 nr_node_put(nr_node);
339 return -EINVAL;
340 }
341
342 nr_node_lock(nr_node);
343 for (i = 0; i < nr_node->count; i++) {
344 if (nr_node->routes[i].neighbour == nr_neigh) {
345 nr_neigh->count--;
346 nr_neigh_put(nr_neigh);
347
348 if (nr_neigh->count == 0 && !nr_neigh->locked)
349 nr_remove_neigh(nr_neigh);
350 nr_neigh_put(nr_neigh);
351
352 nr_node->count--;
353
354 if (nr_node->count == 0) {
355 nr_remove_node(nr_node);
356 } else {
357 switch (i) {
358 case 0:
359 nr_node->routes[0] = nr_node->routes[1];
360 fallthrough;
361 case 1:
362 nr_node->routes[1] = nr_node->routes[2];
363 fallthrough;
364 case 2:
365 break;
366 }
367 nr_node_put(nr_node);
368 }
369 nr_node_unlock(nr_node);
370
371 return 0;
372 }
373 }
374 nr_neigh_put(nr_neigh);
375 nr_node_unlock(nr_node);
376 nr_node_put(nr_node);
377
378 return -EINVAL;
379}
380
381/*
382 * Lock a neighbour with a quality.
383 */
384static int __must_check nr_add_neigh(ax25_address *callsign,
385 ax25_digi *ax25_digi, struct net_device *dev, unsigned int quality)
386{
387 struct nr_neigh *nr_neigh;
388
389 nr_neigh = nr_neigh_get_dev(callsign, dev);
390 if (nr_neigh) {
391 nr_neigh->quality = quality;
392 nr_neigh->locked = 1;
393 nr_neigh_put(nr_neigh);
394 return 0;
395 }
396
397 if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL)
398 return -ENOMEM;
399
400 nr_neigh->callsign = *callsign;
401 nr_neigh->digipeat = NULL;
402 nr_neigh->ax25 = NULL;
403 nr_neigh->dev = dev;
404 nr_neigh->quality = quality;
405 nr_neigh->locked = 1;
406 nr_neigh->count = 0;
407 nr_neigh->number = nr_neigh_no++;
408 nr_neigh->failed = 0;
409 refcount_set(&nr_neigh->refcount, 1);
410
411 if (ax25_digi != NULL && ax25_digi->ndigi > 0) {
412 nr_neigh->digipeat = kmemdup(ax25_digi, sizeof(*ax25_digi),
413 GFP_KERNEL);
414 if (nr_neigh->digipeat == NULL) {
415 kfree(nr_neigh);
416 return -ENOMEM;
417 }
418 }
419
420 spin_lock_bh(&nr_neigh_list_lock);
421 hlist_add_head(&nr_neigh->neigh_node, &nr_neigh_list);
422 /* refcount is initialized at 1 */
423 spin_unlock_bh(&nr_neigh_list_lock);
424
425 return 0;
426}
427
428/*
429 * "Delete" a neighbour. The neighbour is only removed if the number
430 * of nodes that may use it is zero.
431 */
432static int nr_del_neigh(ax25_address *callsign, struct net_device *dev, unsigned int quality)
433{
434 struct nr_neigh *nr_neigh;
435
436 nr_neigh = nr_neigh_get_dev(callsign, dev);
437
438 if (nr_neigh == NULL) return -EINVAL;
439
440 nr_neigh->quality = quality;
441 nr_neigh->locked = 0;
442
443 if (nr_neigh->count == 0)
444 nr_remove_neigh(nr_neigh);
445 nr_neigh_put(nr_neigh);
446
447 return 0;
448}
449
450/*
451 * Decrement the obsolescence count by one. If a route is reduced to a
452 * count of zero, remove it. Also remove any unlocked neighbours with
453 * zero nodes routing via it.
454 */
455static int nr_dec_obs(void)
456{
457 struct nr_neigh *nr_neigh;
458 struct nr_node *s;
459 struct hlist_node *nodet;
460 int i;
461
462 spin_lock_bh(&nr_node_list_lock);
463 nr_node_for_each_safe(s, nodet, &nr_node_list) {
464 nr_node_lock(s);
465 for (i = 0; i < s->count; i++) {
466 switch (s->routes[i].obs_count) {
467 case 0: /* A locked entry */
468 break;
469
470 case 1: /* From 1 -> 0 */
471 nr_neigh = s->routes[i].neighbour;
472
473 nr_neigh->count--;
474 nr_neigh_put(nr_neigh);
475
476 if (nr_neigh->count == 0 && !nr_neigh->locked)
477 nr_remove_neigh(nr_neigh);
478
479 s->count--;
480
481 switch (i) {
482 case 0:
483 s->routes[0] = s->routes[1];
484 fallthrough;
485 case 1:
486 s->routes[1] = s->routes[2];
487 break;
488 case 2:
489 break;
490 }
491 break;
492
493 default:
494 s->routes[i].obs_count--;
495 break;
496
497 }
498 }
499
500 if (s->count <= 0)
501 nr_remove_node_locked(s);
502 nr_node_unlock(s);
503 }
504 spin_unlock_bh(&nr_node_list_lock);
505
506 return 0;
507}
508
509/*
510 * A device has been removed. Remove its routes and neighbours.
511 */
512void nr_rt_device_down(struct net_device *dev)
513{
514 struct nr_neigh *s;
515 struct hlist_node *nodet, *node2t;
516 struct nr_node *t;
517 int i;
518
519 spin_lock_bh(&nr_neigh_list_lock);
520 nr_neigh_for_each_safe(s, nodet, &nr_neigh_list) {
521 if (s->dev == dev) {
522 spin_lock_bh(&nr_node_list_lock);
523 nr_node_for_each_safe(t, node2t, &nr_node_list) {
524 nr_node_lock(t);
525 for (i = 0; i < t->count; i++) {
526 if (t->routes[i].neighbour == s) {
527 t->count--;
528
529 switch (i) {
530 case 0:
531 t->routes[0] = t->routes[1];
532 fallthrough;
533 case 1:
534 t->routes[1] = t->routes[2];
535 break;
536 case 2:
537 break;
538 }
539 }
540 }
541
542 if (t->count <= 0)
543 nr_remove_node_locked(t);
544 nr_node_unlock(t);
545 }
546 spin_unlock_bh(&nr_node_list_lock);
547
548 nr_remove_neigh_locked(s);
549 }
550 }
551 spin_unlock_bh(&nr_neigh_list_lock);
552}
553
554/*
555 * Check that the device given is a valid AX.25 interface that is "up".
556 * Or a valid ethernet interface with an AX.25 callsign binding.
557 */
558static struct net_device *nr_ax25_dev_get(char *devname)
559{
560 struct net_device *dev;
561
562 if ((dev = dev_get_by_name(&init_net, devname)) == NULL)
563 return NULL;
564
565 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_AX25)
566 return dev;
567
568 dev_put(dev);
569 return NULL;
570}
571
572/*
573 * Find the first active NET/ROM device, usually "nr0".
574 */
575struct net_device *nr_dev_first(void)
576{
577 struct net_device *dev, *first = NULL;
578
579 rcu_read_lock();
580 for_each_netdev_rcu(&init_net, dev) {
581 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM)
582 if (first == NULL || strncmp(dev->name, first->name, 3) < 0)
583 first = dev;
584 }
585 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 < 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 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 (!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 <asm/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/netfilter.h>
35#include <linux/init.h>
36#include <linux/spinlock.h>
37#include <net/netrom.h>
38#include <linux/seq_file.h>
39#include <linux/export.h>
40
41static unsigned int nr_neigh_no = 1;
42
43static HLIST_HEAD(nr_node_list);
44static DEFINE_SPINLOCK(nr_node_list_lock);
45static HLIST_HEAD(nr_neigh_list);
46static DEFINE_SPINLOCK(nr_neigh_list_lock);
47
48static struct nr_node *nr_node_get(ax25_address *callsign)
49{
50 struct nr_node *found = NULL;
51 struct nr_node *nr_node;
52
53 spin_lock_bh(&nr_node_list_lock);
54 nr_node_for_each(nr_node, &nr_node_list)
55 if (ax25cmp(callsign, &nr_node->callsign) == 0) {
56 nr_node_hold(nr_node);
57 found = nr_node;
58 break;
59 }
60 spin_unlock_bh(&nr_node_list_lock);
61 return found;
62}
63
64static struct nr_neigh *nr_neigh_get_dev(ax25_address *callsign,
65 struct net_device *dev)
66{
67 struct nr_neigh *found = NULL;
68 struct nr_neigh *nr_neigh;
69
70 spin_lock_bh(&nr_neigh_list_lock);
71 nr_neigh_for_each(nr_neigh, &nr_neigh_list)
72 if (ax25cmp(callsign, &nr_neigh->callsign) == 0 &&
73 nr_neigh->dev == dev) {
74 nr_neigh_hold(nr_neigh);
75 found = nr_neigh;
76 break;
77 }
78 spin_unlock_bh(&nr_neigh_list_lock);
79 return found;
80}
81
82static void nr_remove_neigh(struct nr_neigh *);
83
84/*
85 * Add a new route to a node, and in the process add the node and the
86 * neighbour if it is new.
87 */
88static int __must_check nr_add_node(ax25_address *nr, const char *mnemonic,
89 ax25_address *ax25, ax25_digi *ax25_digi, struct net_device *dev,
90 int quality, int obs_count)
91{
92 struct nr_node *nr_node;
93 struct nr_neigh *nr_neigh;
94 struct nr_route nr_route;
95 int i, found;
96 struct net_device *odev;
97
98 if ((odev=nr_dev_get(nr)) != NULL) { /* Can't add routes to ourself */
99 dev_put(odev);
100 return -EINVAL;
101 }
102
103 nr_node = nr_node_get(nr);
104
105 nr_neigh = nr_neigh_get_dev(ax25, dev);
106
107 /*
108 * The L2 link to a neighbour has failed in the past
109 * and now a frame comes from this neighbour. We assume
110 * it was a temporary trouble with the link and reset the
111 * routes now (and not wait for a node broadcast).
112 */
113 if (nr_neigh != NULL && nr_neigh->failed != 0 && quality == 0) {
114 struct nr_node *nr_nodet;
115
116 spin_lock_bh(&nr_node_list_lock);
117 nr_node_for_each(nr_nodet, &nr_node_list) {
118 nr_node_lock(nr_nodet);
119 for (i = 0; i < nr_nodet->count; i++)
120 if (nr_nodet->routes[i].neighbour == nr_neigh)
121 if (i < nr_nodet->which)
122 nr_nodet->which = i;
123 nr_node_unlock(nr_nodet);
124 }
125 spin_unlock_bh(&nr_node_list_lock);
126 }
127
128 if (nr_neigh != NULL)
129 nr_neigh->failed = 0;
130
131 if (quality == 0 && nr_neigh != NULL && nr_node != NULL) {
132 nr_neigh_put(nr_neigh);
133 nr_node_put(nr_node);
134 return 0;
135 }
136
137 if (nr_neigh == NULL) {
138 if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL) {
139 if (nr_node)
140 nr_node_put(nr_node);
141 return -ENOMEM;
142 }
143
144 nr_neigh->callsign = *ax25;
145 nr_neigh->digipeat = NULL;
146 nr_neigh->ax25 = NULL;
147 nr_neigh->dev = dev;
148 nr_neigh->quality = sysctl_netrom_default_path_quality;
149 nr_neigh->locked = 0;
150 nr_neigh->count = 0;
151 nr_neigh->number = nr_neigh_no++;
152 nr_neigh->failed = 0;
153 atomic_set(&nr_neigh->refcount, 1);
154
155 if (ax25_digi != NULL && ax25_digi->ndigi > 0) {
156 nr_neigh->digipeat = kmemdup(ax25_digi,
157 sizeof(*ax25_digi),
158 GFP_KERNEL);
159 if (nr_neigh->digipeat == NULL) {
160 kfree(nr_neigh);
161 if (nr_node)
162 nr_node_put(nr_node);
163 return -ENOMEM;
164 }
165 }
166
167 spin_lock_bh(&nr_neigh_list_lock);
168 hlist_add_head(&nr_neigh->neigh_node, &nr_neigh_list);
169 nr_neigh_hold(nr_neigh);
170 spin_unlock_bh(&nr_neigh_list_lock);
171 }
172
173 if (quality != 0 && ax25cmp(nr, ax25) == 0 && !nr_neigh->locked)
174 nr_neigh->quality = quality;
175
176 if (nr_node == NULL) {
177 if ((nr_node = kmalloc(sizeof(*nr_node), GFP_ATOMIC)) == NULL) {
178 if (nr_neigh)
179 nr_neigh_put(nr_neigh);
180 return -ENOMEM;
181 }
182
183 nr_node->callsign = *nr;
184 strcpy(nr_node->mnemonic, mnemonic);
185
186 nr_node->which = 0;
187 nr_node->count = 1;
188 atomic_set(&nr_node->refcount, 1);
189 spin_lock_init(&nr_node->node_lock);
190
191 nr_node->routes[0].quality = quality;
192 nr_node->routes[0].obs_count = obs_count;
193 nr_node->routes[0].neighbour = nr_neigh;
194
195 nr_neigh_hold(nr_neigh);
196 nr_neigh->count++;
197
198 spin_lock_bh(&nr_node_list_lock);
199 hlist_add_head(&nr_node->node_node, &nr_node_list);
200 /* refcount initialized at 1 */
201 spin_unlock_bh(&nr_node_list_lock);
202
203 return 0;
204 }
205 nr_node_lock(nr_node);
206
207 if (quality != 0)
208 strcpy(nr_node->mnemonic, mnemonic);
209
210 for (found = 0, i = 0; i < nr_node->count; i++) {
211 if (nr_node->routes[i].neighbour == nr_neigh) {
212 nr_node->routes[i].quality = quality;
213 nr_node->routes[i].obs_count = obs_count;
214 found = 1;
215 break;
216 }
217 }
218
219 if (!found) {
220 /* We have space at the bottom, slot it in */
221 if (nr_node->count < 3) {
222 nr_node->routes[2] = nr_node->routes[1];
223 nr_node->routes[1] = nr_node->routes[0];
224
225 nr_node->routes[0].quality = quality;
226 nr_node->routes[0].obs_count = obs_count;
227 nr_node->routes[0].neighbour = nr_neigh;
228
229 nr_node->which++;
230 nr_node->count++;
231 nr_neigh_hold(nr_neigh);
232 nr_neigh->count++;
233 } else {
234 /* It must be better than the worst */
235 if (quality > nr_node->routes[2].quality) {
236 nr_node->routes[2].neighbour->count--;
237 nr_neigh_put(nr_node->routes[2].neighbour);
238
239 if (nr_node->routes[2].neighbour->count == 0 && !nr_node->routes[2].neighbour->locked)
240 nr_remove_neigh(nr_node->routes[2].neighbour);
241
242 nr_node->routes[2].quality = quality;
243 nr_node->routes[2].obs_count = obs_count;
244 nr_node->routes[2].neighbour = nr_neigh;
245
246 nr_neigh_hold(nr_neigh);
247 nr_neigh->count++;
248 }
249 }
250 }
251
252 /* Now re-sort the routes in quality order */
253 switch (nr_node->count) {
254 case 3:
255 if (nr_node->routes[1].quality > nr_node->routes[0].quality) {
256 switch (nr_node->which) {
257 case 0:
258 nr_node->which = 1;
259 break;
260 case 1:
261 nr_node->which = 0;
262 break;
263 }
264 nr_route = nr_node->routes[0];
265 nr_node->routes[0] = nr_node->routes[1];
266 nr_node->routes[1] = nr_route;
267 }
268 if (nr_node->routes[2].quality > nr_node->routes[1].quality) {
269 switch (nr_node->which) {
270 case 1: nr_node->which = 2;
271 break;
272
273 case 2: nr_node->which = 1;
274 break;
275
276 default:
277 break;
278 }
279 nr_route = nr_node->routes[1];
280 nr_node->routes[1] = nr_node->routes[2];
281 nr_node->routes[2] = nr_route;
282 }
283 case 2:
284 if (nr_node->routes[1].quality > nr_node->routes[0].quality) {
285 switch (nr_node->which) {
286 case 0: nr_node->which = 1;
287 break;
288
289 case 1: nr_node->which = 0;
290 break;
291
292 default: break;
293 }
294 nr_route = nr_node->routes[0];
295 nr_node->routes[0] = nr_node->routes[1];
296 nr_node->routes[1] = nr_route;
297 }
298 case 1:
299 break;
300 }
301
302 for (i = 0; i < nr_node->count; i++) {
303 if (nr_node->routes[i].neighbour == nr_neigh) {
304 if (i < nr_node->which)
305 nr_node->which = i;
306 break;
307 }
308 }
309
310 nr_neigh_put(nr_neigh);
311 nr_node_unlock(nr_node);
312 nr_node_put(nr_node);
313 return 0;
314}
315
316static inline void __nr_remove_node(struct nr_node *nr_node)
317{
318 hlist_del_init(&nr_node->node_node);
319 nr_node_put(nr_node);
320}
321
322#define nr_remove_node_locked(__node) \
323 __nr_remove_node(__node)
324
325static void nr_remove_node(struct nr_node *nr_node)
326{
327 spin_lock_bh(&nr_node_list_lock);
328 __nr_remove_node(nr_node);
329 spin_unlock_bh(&nr_node_list_lock);
330}
331
332static inline void __nr_remove_neigh(struct nr_neigh *nr_neigh)
333{
334 hlist_del_init(&nr_neigh->neigh_node);
335 nr_neigh_put(nr_neigh);
336}
337
338#define nr_remove_neigh_locked(__neigh) \
339 __nr_remove_neigh(__neigh)
340
341static void nr_remove_neigh(struct nr_neigh *nr_neigh)
342{
343 spin_lock_bh(&nr_neigh_list_lock);
344 __nr_remove_neigh(nr_neigh);
345 spin_unlock_bh(&nr_neigh_list_lock);
346}
347
348/*
349 * "Delete" a node. Strictly speaking remove a route to a node. The node
350 * is only deleted if no routes are left to it.
351 */
352static int nr_del_node(ax25_address *callsign, ax25_address *neighbour, struct net_device *dev)
353{
354 struct nr_node *nr_node;
355 struct nr_neigh *nr_neigh;
356 int i;
357
358 nr_node = nr_node_get(callsign);
359
360 if (nr_node == NULL)
361 return -EINVAL;
362
363 nr_neigh = nr_neigh_get_dev(neighbour, dev);
364
365 if (nr_neigh == NULL) {
366 nr_node_put(nr_node);
367 return -EINVAL;
368 }
369
370 nr_node_lock(nr_node);
371 for (i = 0; i < nr_node->count; i++) {
372 if (nr_node->routes[i].neighbour == nr_neigh) {
373 nr_neigh->count--;
374 nr_neigh_put(nr_neigh);
375
376 if (nr_neigh->count == 0 && !nr_neigh->locked)
377 nr_remove_neigh(nr_neigh);
378 nr_neigh_put(nr_neigh);
379
380 nr_node->count--;
381
382 if (nr_node->count == 0) {
383 nr_remove_node(nr_node);
384 } else {
385 switch (i) {
386 case 0:
387 nr_node->routes[0] = nr_node->routes[1];
388 case 1:
389 nr_node->routes[1] = nr_node->routes[2];
390 case 2:
391 break;
392 }
393 nr_node_put(nr_node);
394 }
395 nr_node_unlock(nr_node);
396
397 return 0;
398 }
399 }
400 nr_neigh_put(nr_neigh);
401 nr_node_unlock(nr_node);
402 nr_node_put(nr_node);
403
404 return -EINVAL;
405}
406
407/*
408 * Lock a neighbour with a quality.
409 */
410static int __must_check nr_add_neigh(ax25_address *callsign,
411 ax25_digi *ax25_digi, struct net_device *dev, unsigned int quality)
412{
413 struct nr_neigh *nr_neigh;
414
415 nr_neigh = nr_neigh_get_dev(callsign, dev);
416 if (nr_neigh) {
417 nr_neigh->quality = quality;
418 nr_neigh->locked = 1;
419 nr_neigh_put(nr_neigh);
420 return 0;
421 }
422
423 if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL)
424 return -ENOMEM;
425
426 nr_neigh->callsign = *callsign;
427 nr_neigh->digipeat = NULL;
428 nr_neigh->ax25 = NULL;
429 nr_neigh->dev = dev;
430 nr_neigh->quality = quality;
431 nr_neigh->locked = 1;
432 nr_neigh->count = 0;
433 nr_neigh->number = nr_neigh_no++;
434 nr_neigh->failed = 0;
435 atomic_set(&nr_neigh->refcount, 1);
436
437 if (ax25_digi != NULL && ax25_digi->ndigi > 0) {
438 nr_neigh->digipeat = kmemdup(ax25_digi, sizeof(*ax25_digi),
439 GFP_KERNEL);
440 if (nr_neigh->digipeat == NULL) {
441 kfree(nr_neigh);
442 return -ENOMEM;
443 }
444 }
445
446 spin_lock_bh(&nr_neigh_list_lock);
447 hlist_add_head(&nr_neigh->neigh_node, &nr_neigh_list);
448 /* refcount is initialized at 1 */
449 spin_unlock_bh(&nr_neigh_list_lock);
450
451 return 0;
452}
453
454/*
455 * "Delete" a neighbour. The neighbour is only removed if the number
456 * of nodes that may use it is zero.
457 */
458static int nr_del_neigh(ax25_address *callsign, struct net_device *dev, unsigned int quality)
459{
460 struct nr_neigh *nr_neigh;
461
462 nr_neigh = nr_neigh_get_dev(callsign, dev);
463
464 if (nr_neigh == NULL) return -EINVAL;
465
466 nr_neigh->quality = quality;
467 nr_neigh->locked = 0;
468
469 if (nr_neigh->count == 0)
470 nr_remove_neigh(nr_neigh);
471 nr_neigh_put(nr_neigh);
472
473 return 0;
474}
475
476/*
477 * Decrement the obsolescence count by one. If a route is reduced to a
478 * count of zero, remove it. Also remove any unlocked neighbours with
479 * zero nodes routing via it.
480 */
481static int nr_dec_obs(void)
482{
483 struct nr_neigh *nr_neigh;
484 struct nr_node *s;
485 struct hlist_node *nodet;
486 int i;
487
488 spin_lock_bh(&nr_node_list_lock);
489 nr_node_for_each_safe(s, nodet, &nr_node_list) {
490 nr_node_lock(s);
491 for (i = 0; i < s->count; i++) {
492 switch (s->routes[i].obs_count) {
493 case 0: /* A locked entry */
494 break;
495
496 case 1: /* From 1 -> 0 */
497 nr_neigh = s->routes[i].neighbour;
498
499 nr_neigh->count--;
500 nr_neigh_put(nr_neigh);
501
502 if (nr_neigh->count == 0 && !nr_neigh->locked)
503 nr_remove_neigh(nr_neigh);
504
505 s->count--;
506
507 switch (i) {
508 case 0:
509 s->routes[0] = s->routes[1];
510 /* Fallthrough */
511 case 1:
512 s->routes[1] = s->routes[2];
513 case 2:
514 break;
515 }
516 break;
517
518 default:
519 s->routes[i].obs_count--;
520 break;
521
522 }
523 }
524
525 if (s->count <= 0)
526 nr_remove_node_locked(s);
527 nr_node_unlock(s);
528 }
529 spin_unlock_bh(&nr_node_list_lock);
530
531 return 0;
532}
533
534/*
535 * A device has been removed. Remove its routes and neighbours.
536 */
537void nr_rt_device_down(struct net_device *dev)
538{
539 struct nr_neigh *s;
540 struct hlist_node *nodet, *node2t;
541 struct nr_node *t;
542 int i;
543
544 spin_lock_bh(&nr_neigh_list_lock);
545 nr_neigh_for_each_safe(s, nodet, &nr_neigh_list) {
546 if (s->dev == dev) {
547 spin_lock_bh(&nr_node_list_lock);
548 nr_node_for_each_safe(t, node2t, &nr_node_list) {
549 nr_node_lock(t);
550 for (i = 0; i < t->count; i++) {
551 if (t->routes[i].neighbour == s) {
552 t->count--;
553
554 switch (i) {
555 case 0:
556 t->routes[0] = t->routes[1];
557 case 1:
558 t->routes[1] = t->routes[2];
559 case 2:
560 break;
561 }
562 }
563 }
564
565 if (t->count <= 0)
566 nr_remove_node_locked(t);
567 nr_node_unlock(t);
568 }
569 spin_unlock_bh(&nr_node_list_lock);
570
571 nr_remove_neigh_locked(s);
572 }
573 }
574 spin_unlock_bh(&nr_neigh_list_lock);
575}
576
577/*
578 * Check that the device given is a valid AX.25 interface that is "up".
579 * Or a valid ethernet interface with an AX.25 callsign binding.
580 */
581static struct net_device *nr_ax25_dev_get(char *devname)
582{
583 struct net_device *dev;
584
585 if ((dev = dev_get_by_name(&init_net, devname)) == NULL)
586 return NULL;
587
588 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_AX25)
589 return dev;
590
591 dev_put(dev);
592 return NULL;
593}
594
595/*
596 * Find the first active NET/ROM device, usually "nr0".
597 */
598struct net_device *nr_dev_first(void)
599{
600 struct net_device *dev, *first = NULL;
601
602 rcu_read_lock();
603 for_each_netdev_rcu(&init_net, dev) {
604 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM)
605 if (first == NULL || strncmp(dev->name, first->name, 3) < 0)
606 first = dev;
607 }
608 if (first)
609 dev_hold(first);
610 rcu_read_unlock();
611
612 return first;
613}
614
615/*
616 * Find the NET/ROM device for the given callsign.
617 */
618struct net_device *nr_dev_get(ax25_address *addr)
619{
620 struct net_device *dev;
621
622 rcu_read_lock();
623 for_each_netdev_rcu(&init_net, dev) {
624 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM &&
625 ax25cmp(addr, (ax25_address *)dev->dev_addr) == 0) {
626 dev_hold(dev);
627 goto out;
628 }
629 }
630 dev = NULL;
631out:
632 rcu_read_unlock();
633 return dev;
634}
635
636static ax25_digi *nr_call_to_digi(ax25_digi *digi, int ndigis,
637 ax25_address *digipeaters)
638{
639 int i;
640
641 if (ndigis == 0)
642 return NULL;
643
644 for (i = 0; i < ndigis; i++) {
645 digi->calls[i] = digipeaters[i];
646 digi->repeated[i] = 0;
647 }
648
649 digi->ndigi = ndigis;
650 digi->lastrepeat = -1;
651
652 return digi;
653}
654
655/*
656 * Handle the ioctls that control the routing functions.
657 */
658int nr_rt_ioctl(unsigned int cmd, void __user *arg)
659{
660 struct nr_route_struct nr_route;
661 struct net_device *dev;
662 ax25_digi digi;
663 int ret;
664
665 switch (cmd) {
666 case SIOCADDRT:
667 if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct)))
668 return -EFAULT;
669 if (nr_route.ndigis > AX25_MAX_DIGIS)
670 return -EINVAL;
671 if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL)
672 return -EINVAL;
673 switch (nr_route.type) {
674 case NETROM_NODE:
675 if (strnlen(nr_route.mnemonic, 7) == 7) {
676 ret = -EINVAL;
677 break;
678 }
679
680 ret = nr_add_node(&nr_route.callsign,
681 nr_route.mnemonic,
682 &nr_route.neighbour,
683 nr_call_to_digi(&digi, nr_route.ndigis,
684 nr_route.digipeaters),
685 dev, nr_route.quality,
686 nr_route.obs_count);
687 break;
688 case NETROM_NEIGH:
689 ret = nr_add_neigh(&nr_route.callsign,
690 nr_call_to_digi(&digi, nr_route.ndigis,
691 nr_route.digipeaters),
692 dev, nr_route.quality);
693 break;
694 default:
695 ret = -EINVAL;
696 }
697 dev_put(dev);
698 return ret;
699
700 case SIOCDELRT:
701 if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct)))
702 return -EFAULT;
703 if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL)
704 return -EINVAL;
705 switch (nr_route.type) {
706 case NETROM_NODE:
707 ret = nr_del_node(&nr_route.callsign,
708 &nr_route.neighbour, dev);
709 break;
710 case NETROM_NEIGH:
711 ret = nr_del_neigh(&nr_route.callsign,
712 dev, nr_route.quality);
713 break;
714 default:
715 ret = -EINVAL;
716 }
717 dev_put(dev);
718 return ret;
719
720 case SIOCNRDECOBS:
721 return nr_dec_obs();
722
723 default:
724 return -EINVAL;
725 }
726
727 return 0;
728}
729
730/*
731 * A level 2 link has timed out, therefore it appears to be a poor link,
732 * then don't use that neighbour until it is reset.
733 */
734void nr_link_failed(ax25_cb *ax25, int reason)
735{
736 struct nr_neigh *s, *nr_neigh = NULL;
737 struct nr_node *nr_node = NULL;
738
739 spin_lock_bh(&nr_neigh_list_lock);
740 nr_neigh_for_each(s, &nr_neigh_list) {
741 if (s->ax25 == ax25) {
742 nr_neigh_hold(s);
743 nr_neigh = s;
744 break;
745 }
746 }
747 spin_unlock_bh(&nr_neigh_list_lock);
748
749 if (nr_neigh == NULL)
750 return;
751
752 nr_neigh->ax25 = NULL;
753 ax25_cb_put(ax25);
754
755 if (++nr_neigh->failed < sysctl_netrom_link_fails_count) {
756 nr_neigh_put(nr_neigh);
757 return;
758 }
759 spin_lock_bh(&nr_node_list_lock);
760 nr_node_for_each(nr_node, &nr_node_list) {
761 nr_node_lock(nr_node);
762 if (nr_node->which < nr_node->count &&
763 nr_node->routes[nr_node->which].neighbour == nr_neigh)
764 nr_node->which++;
765 nr_node_unlock(nr_node);
766 }
767 spin_unlock_bh(&nr_node_list_lock);
768 nr_neigh_put(nr_neigh);
769}
770
771/*
772 * Route a frame to an appropriate AX.25 connection. A NULL ax25_cb
773 * indicates an internally generated frame.
774 */
775int nr_route_frame(struct sk_buff *skb, ax25_cb *ax25)
776{
777 ax25_address *nr_src, *nr_dest;
778 struct nr_neigh *nr_neigh;
779 struct nr_node *nr_node;
780 struct net_device *dev;
781 unsigned char *dptr;
782 ax25_cb *ax25s;
783 int ret;
784 struct sk_buff *skbn;
785
786
787 nr_src = (ax25_address *)(skb->data + 0);
788 nr_dest = (ax25_address *)(skb->data + 7);
789
790 if (ax25 != NULL) {
791 ret = nr_add_node(nr_src, "", &ax25->dest_addr, ax25->digipeat,
792 ax25->ax25_dev->dev, 0,
793 sysctl_netrom_obsolescence_count_initialiser);
794 if (ret)
795 return ret;
796 }
797
798 if ((dev = nr_dev_get(nr_dest)) != NULL) { /* Its for me */
799 if (ax25 == NULL) /* Its from me */
800 ret = nr_loopback_queue(skb);
801 else
802 ret = nr_rx_frame(skb, dev);
803 dev_put(dev);
804 return ret;
805 }
806
807 if (!sysctl_netrom_routing_control && ax25 != NULL)
808 return 0;
809
810 /* Its Time-To-Live has expired */
811 if (skb->data[14] == 1) {
812 return 0;
813 }
814
815 nr_node = nr_node_get(nr_dest);
816 if (nr_node == NULL)
817 return 0;
818 nr_node_lock(nr_node);
819
820 if (nr_node->which >= nr_node->count) {
821 nr_node_unlock(nr_node);
822 nr_node_put(nr_node);
823 return 0;
824 }
825
826 nr_neigh = nr_node->routes[nr_node->which].neighbour;
827
828 if ((dev = nr_dev_first()) == NULL) {
829 nr_node_unlock(nr_node);
830 nr_node_put(nr_node);
831 return 0;
832 }
833
834 /* We are going to change the netrom headers so we should get our
835 own skb, we also did not know until now how much header space
836 we had to reserve... - RXQ */
837 if ((skbn=skb_copy_expand(skb, dev->hard_header_len, 0, GFP_ATOMIC)) == NULL) {
838 nr_node_unlock(nr_node);
839 nr_node_put(nr_node);
840 dev_put(dev);
841 return 0;
842 }
843 kfree_skb(skb);
844 skb=skbn;
845 skb->data[14]--;
846
847 dptr = skb_push(skb, 1);
848 *dptr = AX25_P_NETROM;
849
850 ax25s = nr_neigh->ax25;
851 nr_neigh->ax25 = ax25_send_frame(skb, 256,
852 (ax25_address *)dev->dev_addr,
853 &nr_neigh->callsign,
854 nr_neigh->digipeat, nr_neigh->dev);
855 if (ax25s)
856 ax25_cb_put(ax25s);
857
858 dev_put(dev);
859 ret = (nr_neigh->ax25 != NULL);
860 nr_node_unlock(nr_node);
861 nr_node_put(nr_node);
862
863 return ret;
864}
865
866#ifdef CONFIG_PROC_FS
867
868static void *nr_node_start(struct seq_file *seq, loff_t *pos)
869{
870 spin_lock_bh(&nr_node_list_lock);
871 return seq_hlist_start_head(&nr_node_list, *pos);
872}
873
874static void *nr_node_next(struct seq_file *seq, void *v, loff_t *pos)
875{
876 return seq_hlist_next(v, &nr_node_list, pos);
877}
878
879static void nr_node_stop(struct seq_file *seq, void *v)
880{
881 spin_unlock_bh(&nr_node_list_lock);
882}
883
884static int nr_node_show(struct seq_file *seq, void *v)
885{
886 char buf[11];
887 int i;
888
889 if (v == SEQ_START_TOKEN)
890 seq_puts(seq,
891 "callsign mnemonic w n qual obs neigh qual obs neigh qual obs neigh\n");
892 else {
893 struct nr_node *nr_node = hlist_entry(v, struct nr_node,
894 node_node);
895
896 nr_node_lock(nr_node);
897 seq_printf(seq, "%-9s %-7s %d %d",
898 ax2asc(buf, &nr_node->callsign),
899 (nr_node->mnemonic[0] == '\0') ? "*" : nr_node->mnemonic,
900 nr_node->which + 1,
901 nr_node->count);
902
903 for (i = 0; i < nr_node->count; i++) {
904 seq_printf(seq, " %3d %d %05d",
905 nr_node->routes[i].quality,
906 nr_node->routes[i].obs_count,
907 nr_node->routes[i].neighbour->number);
908 }
909 nr_node_unlock(nr_node);
910
911 seq_puts(seq, "\n");
912 }
913 return 0;
914}
915
916static const struct seq_operations nr_node_seqops = {
917 .start = nr_node_start,
918 .next = nr_node_next,
919 .stop = nr_node_stop,
920 .show = nr_node_show,
921};
922
923static int nr_node_info_open(struct inode *inode, struct file *file)
924{
925 return seq_open(file, &nr_node_seqops);
926}
927
928const struct file_operations nr_nodes_fops = {
929 .owner = THIS_MODULE,
930 .open = nr_node_info_open,
931 .read = seq_read,
932 .llseek = seq_lseek,
933 .release = seq_release,
934};
935
936static void *nr_neigh_start(struct seq_file *seq, loff_t *pos)
937{
938 spin_lock_bh(&nr_neigh_list_lock);
939 return seq_hlist_start_head(&nr_neigh_list, *pos);
940}
941
942static void *nr_neigh_next(struct seq_file *seq, void *v, loff_t *pos)
943{
944 return seq_hlist_next(v, &nr_neigh_list, pos);
945}
946
947static void nr_neigh_stop(struct seq_file *seq, void *v)
948{
949 spin_unlock_bh(&nr_neigh_list_lock);
950}
951
952static int nr_neigh_show(struct seq_file *seq, void *v)
953{
954 char buf[11];
955 int i;
956
957 if (v == SEQ_START_TOKEN)
958 seq_puts(seq, "addr callsign dev qual lock count failed digipeaters\n");
959 else {
960 struct nr_neigh *nr_neigh;
961
962 nr_neigh = hlist_entry(v, struct nr_neigh, neigh_node);
963 seq_printf(seq, "%05d %-9s %-4s %3d %d %3d %3d",
964 nr_neigh->number,
965 ax2asc(buf, &nr_neigh->callsign),
966 nr_neigh->dev ? nr_neigh->dev->name : "???",
967 nr_neigh->quality,
968 nr_neigh->locked,
969 nr_neigh->count,
970 nr_neigh->failed);
971
972 if (nr_neigh->digipeat != NULL) {
973 for (i = 0; i < nr_neigh->digipeat->ndigi; i++)
974 seq_printf(seq, " %s",
975 ax2asc(buf, &nr_neigh->digipeat->calls[i]));
976 }
977
978 seq_puts(seq, "\n");
979 }
980 return 0;
981}
982
983static const struct seq_operations nr_neigh_seqops = {
984 .start = nr_neigh_start,
985 .next = nr_neigh_next,
986 .stop = nr_neigh_stop,
987 .show = nr_neigh_show,
988};
989
990static int nr_neigh_info_open(struct inode *inode, struct file *file)
991{
992 return seq_open(file, &nr_neigh_seqops);
993}
994
995const struct file_operations nr_neigh_fops = {
996 .owner = THIS_MODULE,
997 .open = nr_neigh_info_open,
998 .read = seq_read,
999 .llseek = seq_lseek,
1000 .release = seq_release,
1001};
1002
1003#endif
1004
1005/*
1006 * Free all memory associated with the nodes and routes lists.
1007 */
1008void __exit nr_rt_free(void)
1009{
1010 struct nr_neigh *s = NULL;
1011 struct nr_node *t = NULL;
1012 struct hlist_node *nodet;
1013
1014 spin_lock_bh(&nr_neigh_list_lock);
1015 spin_lock_bh(&nr_node_list_lock);
1016 nr_node_for_each_safe(t, nodet, &nr_node_list) {
1017 nr_node_lock(t);
1018 nr_remove_node_locked(t);
1019 nr_node_unlock(t);
1020 }
1021 nr_neigh_for_each_safe(s, nodet, &nr_neigh_list) {
1022 while(s->count) {
1023 s->count--;
1024 nr_neigh_put(s);
1025 }
1026 nr_remove_neigh_locked(s);
1027 }
1028 spin_unlock_bh(&nr_node_list_lock);
1029 spin_unlock_bh(&nr_neigh_list_lock);
1030}