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1/*
2 * This program is free software; you can redistribute it and/or modify
3 * it under the terms of the GNU General Public License as published by
4 * the Free Software Foundation; either version 2 of the License, or
5 * (at your option) any later version.
6 *
7 * Copyright Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
8 * Copyright Alan Cox GW4PTS (alan@lxorguk.ukuu.org.uk)
9 * Copyright Tomi Manninen OH2BNS (oh2bns@sral.fi)
10 */
11#include <linux/errno.h>
12#include <linux/types.h>
13#include <linux/socket.h>
14#include <linux/in.h>
15#include <linux/kernel.h>
16#include <linux/timer.h>
17#include <linux/string.h>
18#include <linux/sockios.h>
19#include <linux/net.h>
20#include <linux/slab.h>
21#include <net/ax25.h>
22#include <linux/inet.h>
23#include <linux/netdevice.h>
24#include <net/arp.h>
25#include <linux/if_arp.h>
26#include <linux/skbuff.h>
27#include <net/sock.h>
28#include <asm/uaccess.h>
29#include <asm/system.h>
30#include <linux/fcntl.h>
31#include <linux/termios.h> /* For TIOCINQ/OUTQ */
32#include <linux/mm.h>
33#include <linux/interrupt.h>
34#include <linux/notifier.h>
35#include <linux/netfilter.h>
36#include <linux/init.h>
37#include <linux/spinlock.h>
38#include <net/netrom.h>
39#include <linux/seq_file.h>
40
41static unsigned int nr_neigh_no = 1;
42
43static HLIST_HEAD(nr_node_list);
44static DEFINE_SPINLOCK(nr_node_list_lock);
45static HLIST_HEAD(nr_neigh_list);
46static DEFINE_SPINLOCK(nr_neigh_list_lock);
47
48static struct nr_node *nr_node_get(ax25_address *callsign)
49{
50 struct nr_node *found = NULL;
51 struct nr_node *nr_node;
52 struct hlist_node *node;
53
54 spin_lock_bh(&nr_node_list_lock);
55 nr_node_for_each(nr_node, node, &nr_node_list)
56 if (ax25cmp(callsign, &nr_node->callsign) == 0) {
57 nr_node_hold(nr_node);
58 found = nr_node;
59 break;
60 }
61 spin_unlock_bh(&nr_node_list_lock);
62 return found;
63}
64
65static struct nr_neigh *nr_neigh_get_dev(ax25_address *callsign,
66 struct net_device *dev)
67{
68 struct nr_neigh *found = NULL;
69 struct nr_neigh *nr_neigh;
70 struct hlist_node *node;
71
72 spin_lock_bh(&nr_neigh_list_lock);
73 nr_neigh_for_each(nr_neigh, node, &nr_neigh_list)
74 if (ax25cmp(callsign, &nr_neigh->callsign) == 0 &&
75 nr_neigh->dev == dev) {
76 nr_neigh_hold(nr_neigh);
77 found = nr_neigh;
78 break;
79 }
80 spin_unlock_bh(&nr_neigh_list_lock);
81 return found;
82}
83
84static void nr_remove_neigh(struct nr_neigh *);
85
86/*
87 * Add a new route to a node, and in the process add the node and the
88 * neighbour if it is new.
89 */
90static int __must_check nr_add_node(ax25_address *nr, const char *mnemonic,
91 ax25_address *ax25, ax25_digi *ax25_digi, struct net_device *dev,
92 int quality, int obs_count)
93{
94 struct nr_node *nr_node;
95 struct nr_neigh *nr_neigh;
96 struct nr_route nr_route;
97 int i, found;
98 struct net_device *odev;
99
100 if ((odev=nr_dev_get(nr)) != NULL) { /* Can't add routes to ourself */
101 dev_put(odev);
102 return -EINVAL;
103 }
104
105 nr_node = nr_node_get(nr);
106
107 nr_neigh = nr_neigh_get_dev(ax25, dev);
108
109 /*
110 * The L2 link to a neighbour has failed in the past
111 * and now a frame comes from this neighbour. We assume
112 * it was a temporary trouble with the link and reset the
113 * routes now (and not wait for a node broadcast).
114 */
115 if (nr_neigh != NULL && nr_neigh->failed != 0 && quality == 0) {
116 struct nr_node *nr_nodet;
117 struct hlist_node *node;
118
119 spin_lock_bh(&nr_node_list_lock);
120 nr_node_for_each(nr_nodet, node, &nr_node_list) {
121 nr_node_lock(nr_nodet);
122 for (i = 0; i < nr_nodet->count; i++)
123 if (nr_nodet->routes[i].neighbour == nr_neigh)
124 if (i < nr_nodet->which)
125 nr_nodet->which = i;
126 nr_node_unlock(nr_nodet);
127 }
128 spin_unlock_bh(&nr_node_list_lock);
129 }
130
131 if (nr_neigh != NULL)
132 nr_neigh->failed = 0;
133
134 if (quality == 0 && nr_neigh != NULL && nr_node != NULL) {
135 nr_neigh_put(nr_neigh);
136 nr_node_put(nr_node);
137 return 0;
138 }
139
140 if (nr_neigh == NULL) {
141 if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL) {
142 if (nr_node)
143 nr_node_put(nr_node);
144 return -ENOMEM;
145 }
146
147 nr_neigh->callsign = *ax25;
148 nr_neigh->digipeat = NULL;
149 nr_neigh->ax25 = NULL;
150 nr_neigh->dev = dev;
151 nr_neigh->quality = sysctl_netrom_default_path_quality;
152 nr_neigh->locked = 0;
153 nr_neigh->count = 0;
154 nr_neigh->number = nr_neigh_no++;
155 nr_neigh->failed = 0;
156 atomic_set(&nr_neigh->refcount, 1);
157
158 if (ax25_digi != NULL && ax25_digi->ndigi > 0) {
159 nr_neigh->digipeat = kmemdup(ax25_digi,
160 sizeof(*ax25_digi),
161 GFP_KERNEL);
162 if (nr_neigh->digipeat == NULL) {
163 kfree(nr_neigh);
164 if (nr_node)
165 nr_node_put(nr_node);
166 return -ENOMEM;
167 }
168 }
169
170 spin_lock_bh(&nr_neigh_list_lock);
171 hlist_add_head(&nr_neigh->neigh_node, &nr_neigh_list);
172 nr_neigh_hold(nr_neigh);
173 spin_unlock_bh(&nr_neigh_list_lock);
174 }
175
176 if (quality != 0 && ax25cmp(nr, ax25) == 0 && !nr_neigh->locked)
177 nr_neigh->quality = quality;
178
179 if (nr_node == NULL) {
180 if ((nr_node = kmalloc(sizeof(*nr_node), GFP_ATOMIC)) == NULL) {
181 if (nr_neigh)
182 nr_neigh_put(nr_neigh);
183 return -ENOMEM;
184 }
185
186 nr_node->callsign = *nr;
187 strcpy(nr_node->mnemonic, mnemonic);
188
189 nr_node->which = 0;
190 nr_node->count = 1;
191 atomic_set(&nr_node->refcount, 1);
192 spin_lock_init(&nr_node->node_lock);
193
194 nr_node->routes[0].quality = quality;
195 nr_node->routes[0].obs_count = obs_count;
196 nr_node->routes[0].neighbour = nr_neigh;
197
198 nr_neigh_hold(nr_neigh);
199 nr_neigh->count++;
200
201 spin_lock_bh(&nr_node_list_lock);
202 hlist_add_head(&nr_node->node_node, &nr_node_list);
203 /* refcount initialized at 1 */
204 spin_unlock_bh(&nr_node_list_lock);
205
206 return 0;
207 }
208 nr_node_lock(nr_node);
209
210 if (quality != 0)
211 strcpy(nr_node->mnemonic, mnemonic);
212
213 for (found = 0, i = 0; i < nr_node->count; i++) {
214 if (nr_node->routes[i].neighbour == nr_neigh) {
215 nr_node->routes[i].quality = quality;
216 nr_node->routes[i].obs_count = obs_count;
217 found = 1;
218 break;
219 }
220 }
221
222 if (!found) {
223 /* We have space at the bottom, slot it in */
224 if (nr_node->count < 3) {
225 nr_node->routes[2] = nr_node->routes[1];
226 nr_node->routes[1] = nr_node->routes[0];
227
228 nr_node->routes[0].quality = quality;
229 nr_node->routes[0].obs_count = obs_count;
230 nr_node->routes[0].neighbour = nr_neigh;
231
232 nr_node->which++;
233 nr_node->count++;
234 nr_neigh_hold(nr_neigh);
235 nr_neigh->count++;
236 } else {
237 /* It must be better than the worst */
238 if (quality > nr_node->routes[2].quality) {
239 nr_node->routes[2].neighbour->count--;
240 nr_neigh_put(nr_node->routes[2].neighbour);
241
242 if (nr_node->routes[2].neighbour->count == 0 && !nr_node->routes[2].neighbour->locked)
243 nr_remove_neigh(nr_node->routes[2].neighbour);
244
245 nr_node->routes[2].quality = quality;
246 nr_node->routes[2].obs_count = obs_count;
247 nr_node->routes[2].neighbour = nr_neigh;
248
249 nr_neigh_hold(nr_neigh);
250 nr_neigh->count++;
251 }
252 }
253 }
254
255 /* Now re-sort the routes in quality order */
256 switch (nr_node->count) {
257 case 3:
258 if (nr_node->routes[1].quality > nr_node->routes[0].quality) {
259 switch (nr_node->which) {
260 case 0:
261 nr_node->which = 1;
262 break;
263 case 1:
264 nr_node->which = 0;
265 break;
266 }
267 nr_route = nr_node->routes[0];
268 nr_node->routes[0] = nr_node->routes[1];
269 nr_node->routes[1] = nr_route;
270 }
271 if (nr_node->routes[2].quality > nr_node->routes[1].quality) {
272 switch (nr_node->which) {
273 case 1: nr_node->which = 2;
274 break;
275
276 case 2: nr_node->which = 1;
277 break;
278
279 default:
280 break;
281 }
282 nr_route = nr_node->routes[1];
283 nr_node->routes[1] = nr_node->routes[2];
284 nr_node->routes[2] = nr_route;
285 }
286 case 2:
287 if (nr_node->routes[1].quality > nr_node->routes[0].quality) {
288 switch (nr_node->which) {
289 case 0: nr_node->which = 1;
290 break;
291
292 case 1: nr_node->which = 0;
293 break;
294
295 default: break;
296 }
297 nr_route = nr_node->routes[0];
298 nr_node->routes[0] = nr_node->routes[1];
299 nr_node->routes[1] = nr_route;
300 }
301 case 1:
302 break;
303 }
304
305 for (i = 0; i < nr_node->count; i++) {
306 if (nr_node->routes[i].neighbour == nr_neigh) {
307 if (i < nr_node->which)
308 nr_node->which = i;
309 break;
310 }
311 }
312
313 nr_neigh_put(nr_neigh);
314 nr_node_unlock(nr_node);
315 nr_node_put(nr_node);
316 return 0;
317}
318
319static inline void __nr_remove_node(struct nr_node *nr_node)
320{
321 hlist_del_init(&nr_node->node_node);
322 nr_node_put(nr_node);
323}
324
325#define nr_remove_node_locked(__node) \
326 __nr_remove_node(__node)
327
328static void nr_remove_node(struct nr_node *nr_node)
329{
330 spin_lock_bh(&nr_node_list_lock);
331 __nr_remove_node(nr_node);
332 spin_unlock_bh(&nr_node_list_lock);
333}
334
335static inline void __nr_remove_neigh(struct nr_neigh *nr_neigh)
336{
337 hlist_del_init(&nr_neigh->neigh_node);
338 nr_neigh_put(nr_neigh);
339}
340
341#define nr_remove_neigh_locked(__neigh) \
342 __nr_remove_neigh(__neigh)
343
344static void nr_remove_neigh(struct nr_neigh *nr_neigh)
345{
346 spin_lock_bh(&nr_neigh_list_lock);
347 __nr_remove_neigh(nr_neigh);
348 spin_unlock_bh(&nr_neigh_list_lock);
349}
350
351/*
352 * "Delete" a node. Strictly speaking remove a route to a node. The node
353 * is only deleted if no routes are left to it.
354 */
355static int nr_del_node(ax25_address *callsign, ax25_address *neighbour, struct net_device *dev)
356{
357 struct nr_node *nr_node;
358 struct nr_neigh *nr_neigh;
359 int i;
360
361 nr_node = nr_node_get(callsign);
362
363 if (nr_node == NULL)
364 return -EINVAL;
365
366 nr_neigh = nr_neigh_get_dev(neighbour, dev);
367
368 if (nr_neigh == NULL) {
369 nr_node_put(nr_node);
370 return -EINVAL;
371 }
372
373 nr_node_lock(nr_node);
374 for (i = 0; i < nr_node->count; i++) {
375 if (nr_node->routes[i].neighbour == nr_neigh) {
376 nr_neigh->count--;
377 nr_neigh_put(nr_neigh);
378
379 if (nr_neigh->count == 0 && !nr_neigh->locked)
380 nr_remove_neigh(nr_neigh);
381 nr_neigh_put(nr_neigh);
382
383 nr_node->count--;
384
385 if (nr_node->count == 0) {
386 nr_remove_node(nr_node);
387 } else {
388 switch (i) {
389 case 0:
390 nr_node->routes[0] = nr_node->routes[1];
391 case 1:
392 nr_node->routes[1] = nr_node->routes[2];
393 case 2:
394 break;
395 }
396 nr_node_put(nr_node);
397 }
398 nr_node_unlock(nr_node);
399
400 return 0;
401 }
402 }
403 nr_neigh_put(nr_neigh);
404 nr_node_unlock(nr_node);
405 nr_node_put(nr_node);
406
407 return -EINVAL;
408}
409
410/*
411 * Lock a neighbour with a quality.
412 */
413static int __must_check nr_add_neigh(ax25_address *callsign,
414 ax25_digi *ax25_digi, struct net_device *dev, unsigned int quality)
415{
416 struct nr_neigh *nr_neigh;
417
418 nr_neigh = nr_neigh_get_dev(callsign, dev);
419 if (nr_neigh) {
420 nr_neigh->quality = quality;
421 nr_neigh->locked = 1;
422 nr_neigh_put(nr_neigh);
423 return 0;
424 }
425
426 if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL)
427 return -ENOMEM;
428
429 nr_neigh->callsign = *callsign;
430 nr_neigh->digipeat = NULL;
431 nr_neigh->ax25 = NULL;
432 nr_neigh->dev = dev;
433 nr_neigh->quality = quality;
434 nr_neigh->locked = 1;
435 nr_neigh->count = 0;
436 nr_neigh->number = nr_neigh_no++;
437 nr_neigh->failed = 0;
438 atomic_set(&nr_neigh->refcount, 1);
439
440 if (ax25_digi != NULL && ax25_digi->ndigi > 0) {
441 nr_neigh->digipeat = kmemdup(ax25_digi, sizeof(*ax25_digi),
442 GFP_KERNEL);
443 if (nr_neigh->digipeat == NULL) {
444 kfree(nr_neigh);
445 return -ENOMEM;
446 }
447 }
448
449 spin_lock_bh(&nr_neigh_list_lock);
450 hlist_add_head(&nr_neigh->neigh_node, &nr_neigh_list);
451 /* refcount is initialized at 1 */
452 spin_unlock_bh(&nr_neigh_list_lock);
453
454 return 0;
455}
456
457/*
458 * "Delete" a neighbour. The neighbour is only removed if the number
459 * of nodes that may use it is zero.
460 */
461static int nr_del_neigh(ax25_address *callsign, struct net_device *dev, unsigned int quality)
462{
463 struct nr_neigh *nr_neigh;
464
465 nr_neigh = nr_neigh_get_dev(callsign, dev);
466
467 if (nr_neigh == NULL) return -EINVAL;
468
469 nr_neigh->quality = quality;
470 nr_neigh->locked = 0;
471
472 if (nr_neigh->count == 0)
473 nr_remove_neigh(nr_neigh);
474 nr_neigh_put(nr_neigh);
475
476 return 0;
477}
478
479/*
480 * Decrement the obsolescence count by one. If a route is reduced to a
481 * count of zero, remove it. Also remove any unlocked neighbours with
482 * zero nodes routing via it.
483 */
484static int nr_dec_obs(void)
485{
486 struct nr_neigh *nr_neigh;
487 struct nr_node *s;
488 struct hlist_node *node, *nodet;
489 int i;
490
491 spin_lock_bh(&nr_node_list_lock);
492 nr_node_for_each_safe(s, node, nodet, &nr_node_list) {
493 nr_node_lock(s);
494 for (i = 0; i < s->count; i++) {
495 switch (s->routes[i].obs_count) {
496 case 0: /* A locked entry */
497 break;
498
499 case 1: /* From 1 -> 0 */
500 nr_neigh = s->routes[i].neighbour;
501
502 nr_neigh->count--;
503 nr_neigh_put(nr_neigh);
504
505 if (nr_neigh->count == 0 && !nr_neigh->locked)
506 nr_remove_neigh(nr_neigh);
507
508 s->count--;
509
510 switch (i) {
511 case 0:
512 s->routes[0] = s->routes[1];
513 /* Fallthrough */
514 case 1:
515 s->routes[1] = s->routes[2];
516 case 2:
517 break;
518 }
519 break;
520
521 default:
522 s->routes[i].obs_count--;
523 break;
524
525 }
526 }
527
528 if (s->count <= 0)
529 nr_remove_node_locked(s);
530 nr_node_unlock(s);
531 }
532 spin_unlock_bh(&nr_node_list_lock);
533
534 return 0;
535}
536
537/*
538 * A device has been removed. Remove its routes and neighbours.
539 */
540void nr_rt_device_down(struct net_device *dev)
541{
542 struct nr_neigh *s;
543 struct hlist_node *node, *nodet, *node2, *node2t;
544 struct nr_node *t;
545 int i;
546
547 spin_lock_bh(&nr_neigh_list_lock);
548 nr_neigh_for_each_safe(s, node, nodet, &nr_neigh_list) {
549 if (s->dev == dev) {
550 spin_lock_bh(&nr_node_list_lock);
551 nr_node_for_each_safe(t, node2, node2t, &nr_node_list) {
552 nr_node_lock(t);
553 for (i = 0; i < t->count; i++) {
554 if (t->routes[i].neighbour == s) {
555 t->count--;
556
557 switch (i) {
558 case 0:
559 t->routes[0] = t->routes[1];
560 case 1:
561 t->routes[1] = t->routes[2];
562 case 2:
563 break;
564 }
565 }
566 }
567
568 if (t->count <= 0)
569 nr_remove_node_locked(t);
570 nr_node_unlock(t);
571 }
572 spin_unlock_bh(&nr_node_list_lock);
573
574 nr_remove_neigh_locked(s);
575 }
576 }
577 spin_unlock_bh(&nr_neigh_list_lock);
578}
579
580/*
581 * Check that the device given is a valid AX.25 interface that is "up".
582 * Or a valid ethernet interface with an AX.25 callsign binding.
583 */
584static struct net_device *nr_ax25_dev_get(char *devname)
585{
586 struct net_device *dev;
587
588 if ((dev = dev_get_by_name(&init_net, devname)) == NULL)
589 return NULL;
590
591 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_AX25)
592 return dev;
593
594 dev_put(dev);
595 return NULL;
596}
597
598/*
599 * Find the first active NET/ROM device, usually "nr0".
600 */
601struct net_device *nr_dev_first(void)
602{
603 struct net_device *dev, *first = NULL;
604
605 rcu_read_lock();
606 for_each_netdev_rcu(&init_net, dev) {
607 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM)
608 if (first == NULL || strncmp(dev->name, first->name, 3) < 0)
609 first = dev;
610 }
611 if (first)
612 dev_hold(first);
613 rcu_read_unlock();
614
615 return first;
616}
617
618/*
619 * Find the NET/ROM device for the given callsign.
620 */
621struct net_device *nr_dev_get(ax25_address *addr)
622{
623 struct net_device *dev;
624
625 rcu_read_lock();
626 for_each_netdev_rcu(&init_net, dev) {
627 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM &&
628 ax25cmp(addr, (ax25_address *)dev->dev_addr) == 0) {
629 dev_hold(dev);
630 goto out;
631 }
632 }
633 dev = NULL;
634out:
635 rcu_read_unlock();
636 return dev;
637}
638
639static ax25_digi *nr_call_to_digi(ax25_digi *digi, int ndigis,
640 ax25_address *digipeaters)
641{
642 int i;
643
644 if (ndigis == 0)
645 return NULL;
646
647 for (i = 0; i < ndigis; i++) {
648 digi->calls[i] = digipeaters[i];
649 digi->repeated[i] = 0;
650 }
651
652 digi->ndigi = ndigis;
653 digi->lastrepeat = -1;
654
655 return digi;
656}
657
658/*
659 * Handle the ioctls that control the routing functions.
660 */
661int nr_rt_ioctl(unsigned int cmd, void __user *arg)
662{
663 struct nr_route_struct nr_route;
664 struct net_device *dev;
665 ax25_digi digi;
666 int ret;
667
668 switch (cmd) {
669 case SIOCADDRT:
670 if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct)))
671 return -EFAULT;
672 if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL)
673 return -EINVAL;
674 if (nr_route.ndigis < 0 || nr_route.ndigis > AX25_MAX_DIGIS) {
675 dev_put(dev);
676 return -EINVAL;
677 }
678 switch (nr_route.type) {
679 case NETROM_NODE:
680 ret = nr_add_node(&nr_route.callsign,
681 nr_route.mnemonic,
682 &nr_route.neighbour,
683 nr_call_to_digi(&digi, nr_route.ndigis,
684 nr_route.digipeaters),
685 dev, nr_route.quality,
686 nr_route.obs_count);
687 break;
688 case NETROM_NEIGH:
689 ret = nr_add_neigh(&nr_route.callsign,
690 nr_call_to_digi(&digi, nr_route.ndigis,
691 nr_route.digipeaters),
692 dev, nr_route.quality);
693 break;
694 default:
695 ret = -EINVAL;
696 }
697 dev_put(dev);
698 return ret;
699
700 case SIOCDELRT:
701 if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct)))
702 return -EFAULT;
703 if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL)
704 return -EINVAL;
705 switch (nr_route.type) {
706 case NETROM_NODE:
707 ret = nr_del_node(&nr_route.callsign,
708 &nr_route.neighbour, dev);
709 break;
710 case NETROM_NEIGH:
711 ret = nr_del_neigh(&nr_route.callsign,
712 dev, nr_route.quality);
713 break;
714 default:
715 ret = -EINVAL;
716 }
717 dev_put(dev);
718 return ret;
719
720 case SIOCNRDECOBS:
721 return nr_dec_obs();
722
723 default:
724 return -EINVAL;
725 }
726
727 return 0;
728}
729
730/*
731 * A level 2 link has timed out, therefore it appears to be a poor link,
732 * then don't use that neighbour until it is reset.
733 */
734void nr_link_failed(ax25_cb *ax25, int reason)
735{
736 struct nr_neigh *s, *nr_neigh = NULL;
737 struct hlist_node *node;
738 struct nr_node *nr_node = NULL;
739
740 spin_lock_bh(&nr_neigh_list_lock);
741 nr_neigh_for_each(s, node, &nr_neigh_list) {
742 if (s->ax25 == ax25) {
743 nr_neigh_hold(s);
744 nr_neigh = s;
745 break;
746 }
747 }
748 spin_unlock_bh(&nr_neigh_list_lock);
749
750 if (nr_neigh == NULL)
751 return;
752
753 nr_neigh->ax25 = NULL;
754 ax25_cb_put(ax25);
755
756 if (++nr_neigh->failed < sysctl_netrom_link_fails_count) {
757 nr_neigh_put(nr_neigh);
758 return;
759 }
760 spin_lock_bh(&nr_node_list_lock);
761 nr_node_for_each(nr_node, node, &nr_node_list) {
762 nr_node_lock(nr_node);
763 if (nr_node->which < nr_node->count &&
764 nr_node->routes[nr_node->which].neighbour == nr_neigh)
765 nr_node->which++;
766 nr_node_unlock(nr_node);
767 }
768 spin_unlock_bh(&nr_node_list_lock);
769 nr_neigh_put(nr_neigh);
770}
771
772/*
773 * Route a frame to an appropriate AX.25 connection. A NULL ax25_cb
774 * indicates an internally generated frame.
775 */
776int nr_route_frame(struct sk_buff *skb, ax25_cb *ax25)
777{
778 ax25_address *nr_src, *nr_dest;
779 struct nr_neigh *nr_neigh;
780 struct nr_node *nr_node;
781 struct net_device *dev;
782 unsigned char *dptr;
783 ax25_cb *ax25s;
784 int ret;
785 struct sk_buff *skbn;
786
787
788 nr_src = (ax25_address *)(skb->data + 0);
789 nr_dest = (ax25_address *)(skb->data + 7);
790
791 if (ax25 != NULL) {
792 ret = nr_add_node(nr_src, "", &ax25->dest_addr, ax25->digipeat,
793 ax25->ax25_dev->dev, 0,
794 sysctl_netrom_obsolescence_count_initialiser);
795 if (ret)
796 return ret;
797 }
798
799 if ((dev = nr_dev_get(nr_dest)) != NULL) { /* Its for me */
800 if (ax25 == NULL) /* Its from me */
801 ret = nr_loopback_queue(skb);
802 else
803 ret = nr_rx_frame(skb, dev);
804 dev_put(dev);
805 return ret;
806 }
807
808 if (!sysctl_netrom_routing_control && ax25 != NULL)
809 return 0;
810
811 /* Its Time-To-Live has expired */
812 if (skb->data[14] == 1) {
813 return 0;
814 }
815
816 nr_node = nr_node_get(nr_dest);
817 if (nr_node == NULL)
818 return 0;
819 nr_node_lock(nr_node);
820
821 if (nr_node->which >= nr_node->count) {
822 nr_node_unlock(nr_node);
823 nr_node_put(nr_node);
824 return 0;
825 }
826
827 nr_neigh = nr_node->routes[nr_node->which].neighbour;
828
829 if ((dev = nr_dev_first()) == NULL) {
830 nr_node_unlock(nr_node);
831 nr_node_put(nr_node);
832 return 0;
833 }
834
835 /* We are going to change the netrom headers so we should get our
836 own skb, we also did not know until now how much header space
837 we had to reserve... - RXQ */
838 if ((skbn=skb_copy_expand(skb, dev->hard_header_len, 0, GFP_ATOMIC)) == NULL) {
839 nr_node_unlock(nr_node);
840 nr_node_put(nr_node);
841 dev_put(dev);
842 return 0;
843 }
844 kfree_skb(skb);
845 skb=skbn;
846 skb->data[14]--;
847
848 dptr = skb_push(skb, 1);
849 *dptr = AX25_P_NETROM;
850
851 ax25s = nr_neigh->ax25;
852 nr_neigh->ax25 = ax25_send_frame(skb, 256,
853 (ax25_address *)dev->dev_addr,
854 &nr_neigh->callsign,
855 nr_neigh->digipeat, nr_neigh->dev);
856 if (ax25s)
857 ax25_cb_put(ax25s);
858
859 dev_put(dev);
860 ret = (nr_neigh->ax25 != NULL);
861 nr_node_unlock(nr_node);
862 nr_node_put(nr_node);
863
864 return ret;
865}
866
867#ifdef CONFIG_PROC_FS
868
869static void *nr_node_start(struct seq_file *seq, loff_t *pos)
870{
871 spin_lock_bh(&nr_node_list_lock);
872 return seq_hlist_start_head(&nr_node_list, *pos);
873}
874
875static void *nr_node_next(struct seq_file *seq, void *v, loff_t *pos)
876{
877 return seq_hlist_next(v, &nr_node_list, pos);
878}
879
880static void nr_node_stop(struct seq_file *seq, void *v)
881{
882 spin_unlock_bh(&nr_node_list_lock);
883}
884
885static int nr_node_show(struct seq_file *seq, void *v)
886{
887 char buf[11];
888 int i;
889
890 if (v == SEQ_START_TOKEN)
891 seq_puts(seq,
892 "callsign mnemonic w n qual obs neigh qual obs neigh qual obs neigh\n");
893 else {
894 struct nr_node *nr_node = hlist_entry(v, struct nr_node,
895 node_node);
896
897 nr_node_lock(nr_node);
898 seq_printf(seq, "%-9s %-7s %d %d",
899 ax2asc(buf, &nr_node->callsign),
900 (nr_node->mnemonic[0] == '\0') ? "*" : nr_node->mnemonic,
901 nr_node->which + 1,
902 nr_node->count);
903
904 for (i = 0; i < nr_node->count; i++) {
905 seq_printf(seq, " %3d %d %05d",
906 nr_node->routes[i].quality,
907 nr_node->routes[i].obs_count,
908 nr_node->routes[i].neighbour->number);
909 }
910 nr_node_unlock(nr_node);
911
912 seq_puts(seq, "\n");
913 }
914 return 0;
915}
916
917static const struct seq_operations nr_node_seqops = {
918 .start = nr_node_start,
919 .next = nr_node_next,
920 .stop = nr_node_stop,
921 .show = nr_node_show,
922};
923
924static int nr_node_info_open(struct inode *inode, struct file *file)
925{
926 return seq_open(file, &nr_node_seqops);
927}
928
929const struct file_operations nr_nodes_fops = {
930 .owner = THIS_MODULE,
931 .open = nr_node_info_open,
932 .read = seq_read,
933 .llseek = seq_lseek,
934 .release = seq_release,
935};
936
937static void *nr_neigh_start(struct seq_file *seq, loff_t *pos)
938{
939 spin_lock_bh(&nr_neigh_list_lock);
940 return seq_hlist_start_head(&nr_neigh_list, *pos);
941}
942
943static void *nr_neigh_next(struct seq_file *seq, void *v, loff_t *pos)
944{
945 return seq_hlist_next(v, &nr_neigh_list, pos);
946}
947
948static void nr_neigh_stop(struct seq_file *seq, void *v)
949{
950 spin_unlock_bh(&nr_neigh_list_lock);
951}
952
953static int nr_neigh_show(struct seq_file *seq, void *v)
954{
955 char buf[11];
956 int i;
957
958 if (v == SEQ_START_TOKEN)
959 seq_puts(seq, "addr callsign dev qual lock count failed digipeaters\n");
960 else {
961 struct nr_neigh *nr_neigh;
962
963 nr_neigh = hlist_entry(v, struct nr_neigh, neigh_node);
964 seq_printf(seq, "%05d %-9s %-4s %3d %d %3d %3d",
965 nr_neigh->number,
966 ax2asc(buf, &nr_neigh->callsign),
967 nr_neigh->dev ? nr_neigh->dev->name : "???",
968 nr_neigh->quality,
969 nr_neigh->locked,
970 nr_neigh->count,
971 nr_neigh->failed);
972
973 if (nr_neigh->digipeat != NULL) {
974 for (i = 0; i < nr_neigh->digipeat->ndigi; i++)
975 seq_printf(seq, " %s",
976 ax2asc(buf, &nr_neigh->digipeat->calls[i]));
977 }
978
979 seq_puts(seq, "\n");
980 }
981 return 0;
982}
983
984static const struct seq_operations nr_neigh_seqops = {
985 .start = nr_neigh_start,
986 .next = nr_neigh_next,
987 .stop = nr_neigh_stop,
988 .show = nr_neigh_show,
989};
990
991static int nr_neigh_info_open(struct inode *inode, struct file *file)
992{
993 return seq_open(file, &nr_neigh_seqops);
994}
995
996const struct file_operations nr_neigh_fops = {
997 .owner = THIS_MODULE,
998 .open = nr_neigh_info_open,
999 .read = seq_read,
1000 .llseek = seq_lseek,
1001 .release = seq_release,
1002};
1003
1004#endif
1005
1006/*
1007 * Free all memory associated with the nodes and routes lists.
1008 */
1009void __exit nr_rt_free(void)
1010{
1011 struct nr_neigh *s = NULL;
1012 struct nr_node *t = NULL;
1013 struct hlist_node *node, *nodet;
1014
1015 spin_lock_bh(&nr_neigh_list_lock);
1016 spin_lock_bh(&nr_node_list_lock);
1017 nr_node_for_each_safe(t, node, nodet, &nr_node_list) {
1018 nr_node_lock(t);
1019 nr_remove_node_locked(t);
1020 nr_node_unlock(t);
1021 }
1022 nr_neigh_for_each_safe(s, node, nodet, &nr_neigh_list) {
1023 while(s->count) {
1024 s->count--;
1025 nr_neigh_put(s);
1026 }
1027 nr_remove_neigh_locked(s);
1028 }
1029 spin_unlock_bh(&nr_node_list_lock);
1030 spin_unlock_bh(&nr_neigh_list_lock);
1031}
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 struct hlist_node *node;
53
54 spin_lock_bh(&nr_node_list_lock);
55 nr_node_for_each(nr_node, node, &nr_node_list)
56 if (ax25cmp(callsign, &nr_node->callsign) == 0) {
57 nr_node_hold(nr_node);
58 found = nr_node;
59 break;
60 }
61 spin_unlock_bh(&nr_node_list_lock);
62 return found;
63}
64
65static struct nr_neigh *nr_neigh_get_dev(ax25_address *callsign,
66 struct net_device *dev)
67{
68 struct nr_neigh *found = NULL;
69 struct nr_neigh *nr_neigh;
70 struct hlist_node *node;
71
72 spin_lock_bh(&nr_neigh_list_lock);
73 nr_neigh_for_each(nr_neigh, node, &nr_neigh_list)
74 if (ax25cmp(callsign, &nr_neigh->callsign) == 0 &&
75 nr_neigh->dev == dev) {
76 nr_neigh_hold(nr_neigh);
77 found = nr_neigh;
78 break;
79 }
80 spin_unlock_bh(&nr_neigh_list_lock);
81 return found;
82}
83
84static void nr_remove_neigh(struct nr_neigh *);
85
86/*
87 * Add a new route to a node, and in the process add the node and the
88 * neighbour if it is new.
89 */
90static int __must_check nr_add_node(ax25_address *nr, const char *mnemonic,
91 ax25_address *ax25, ax25_digi *ax25_digi, struct net_device *dev,
92 int quality, int obs_count)
93{
94 struct nr_node *nr_node;
95 struct nr_neigh *nr_neigh;
96 struct nr_route nr_route;
97 int i, found;
98 struct net_device *odev;
99
100 if ((odev=nr_dev_get(nr)) != NULL) { /* Can't add routes to ourself */
101 dev_put(odev);
102 return -EINVAL;
103 }
104
105 nr_node = nr_node_get(nr);
106
107 nr_neigh = nr_neigh_get_dev(ax25, dev);
108
109 /*
110 * The L2 link to a neighbour has failed in the past
111 * and now a frame comes from this neighbour. We assume
112 * it was a temporary trouble with the link and reset the
113 * routes now (and not wait for a node broadcast).
114 */
115 if (nr_neigh != NULL && nr_neigh->failed != 0 && quality == 0) {
116 struct nr_node *nr_nodet;
117 struct hlist_node *node;
118
119 spin_lock_bh(&nr_node_list_lock);
120 nr_node_for_each(nr_nodet, node, &nr_node_list) {
121 nr_node_lock(nr_nodet);
122 for (i = 0; i < nr_nodet->count; i++)
123 if (nr_nodet->routes[i].neighbour == nr_neigh)
124 if (i < nr_nodet->which)
125 nr_nodet->which = i;
126 nr_node_unlock(nr_nodet);
127 }
128 spin_unlock_bh(&nr_node_list_lock);
129 }
130
131 if (nr_neigh != NULL)
132 nr_neigh->failed = 0;
133
134 if (quality == 0 && nr_neigh != NULL && nr_node != NULL) {
135 nr_neigh_put(nr_neigh);
136 nr_node_put(nr_node);
137 return 0;
138 }
139
140 if (nr_neigh == NULL) {
141 if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL) {
142 if (nr_node)
143 nr_node_put(nr_node);
144 return -ENOMEM;
145 }
146
147 nr_neigh->callsign = *ax25;
148 nr_neigh->digipeat = NULL;
149 nr_neigh->ax25 = NULL;
150 nr_neigh->dev = dev;
151 nr_neigh->quality = sysctl_netrom_default_path_quality;
152 nr_neigh->locked = 0;
153 nr_neigh->count = 0;
154 nr_neigh->number = nr_neigh_no++;
155 nr_neigh->failed = 0;
156 atomic_set(&nr_neigh->refcount, 1);
157
158 if (ax25_digi != NULL && ax25_digi->ndigi > 0) {
159 nr_neigh->digipeat = kmemdup(ax25_digi,
160 sizeof(*ax25_digi),
161 GFP_KERNEL);
162 if (nr_neigh->digipeat == NULL) {
163 kfree(nr_neigh);
164 if (nr_node)
165 nr_node_put(nr_node);
166 return -ENOMEM;
167 }
168 }
169
170 spin_lock_bh(&nr_neigh_list_lock);
171 hlist_add_head(&nr_neigh->neigh_node, &nr_neigh_list);
172 nr_neigh_hold(nr_neigh);
173 spin_unlock_bh(&nr_neigh_list_lock);
174 }
175
176 if (quality != 0 && ax25cmp(nr, ax25) == 0 && !nr_neigh->locked)
177 nr_neigh->quality = quality;
178
179 if (nr_node == NULL) {
180 if ((nr_node = kmalloc(sizeof(*nr_node), GFP_ATOMIC)) == NULL) {
181 if (nr_neigh)
182 nr_neigh_put(nr_neigh);
183 return -ENOMEM;
184 }
185
186 nr_node->callsign = *nr;
187 strcpy(nr_node->mnemonic, mnemonic);
188
189 nr_node->which = 0;
190 nr_node->count = 1;
191 atomic_set(&nr_node->refcount, 1);
192 spin_lock_init(&nr_node->node_lock);
193
194 nr_node->routes[0].quality = quality;
195 nr_node->routes[0].obs_count = obs_count;
196 nr_node->routes[0].neighbour = nr_neigh;
197
198 nr_neigh_hold(nr_neigh);
199 nr_neigh->count++;
200
201 spin_lock_bh(&nr_node_list_lock);
202 hlist_add_head(&nr_node->node_node, &nr_node_list);
203 /* refcount initialized at 1 */
204 spin_unlock_bh(&nr_node_list_lock);
205
206 return 0;
207 }
208 nr_node_lock(nr_node);
209
210 if (quality != 0)
211 strcpy(nr_node->mnemonic, mnemonic);
212
213 for (found = 0, i = 0; i < nr_node->count; i++) {
214 if (nr_node->routes[i].neighbour == nr_neigh) {
215 nr_node->routes[i].quality = quality;
216 nr_node->routes[i].obs_count = obs_count;
217 found = 1;
218 break;
219 }
220 }
221
222 if (!found) {
223 /* We have space at the bottom, slot it in */
224 if (nr_node->count < 3) {
225 nr_node->routes[2] = nr_node->routes[1];
226 nr_node->routes[1] = nr_node->routes[0];
227
228 nr_node->routes[0].quality = quality;
229 nr_node->routes[0].obs_count = obs_count;
230 nr_node->routes[0].neighbour = nr_neigh;
231
232 nr_node->which++;
233 nr_node->count++;
234 nr_neigh_hold(nr_neigh);
235 nr_neigh->count++;
236 } else {
237 /* It must be better than the worst */
238 if (quality > nr_node->routes[2].quality) {
239 nr_node->routes[2].neighbour->count--;
240 nr_neigh_put(nr_node->routes[2].neighbour);
241
242 if (nr_node->routes[2].neighbour->count == 0 && !nr_node->routes[2].neighbour->locked)
243 nr_remove_neigh(nr_node->routes[2].neighbour);
244
245 nr_node->routes[2].quality = quality;
246 nr_node->routes[2].obs_count = obs_count;
247 nr_node->routes[2].neighbour = nr_neigh;
248
249 nr_neigh_hold(nr_neigh);
250 nr_neigh->count++;
251 }
252 }
253 }
254
255 /* Now re-sort the routes in quality order */
256 switch (nr_node->count) {
257 case 3:
258 if (nr_node->routes[1].quality > nr_node->routes[0].quality) {
259 switch (nr_node->which) {
260 case 0:
261 nr_node->which = 1;
262 break;
263 case 1:
264 nr_node->which = 0;
265 break;
266 }
267 nr_route = nr_node->routes[0];
268 nr_node->routes[0] = nr_node->routes[1];
269 nr_node->routes[1] = nr_route;
270 }
271 if (nr_node->routes[2].quality > nr_node->routes[1].quality) {
272 switch (nr_node->which) {
273 case 1: nr_node->which = 2;
274 break;
275
276 case 2: nr_node->which = 1;
277 break;
278
279 default:
280 break;
281 }
282 nr_route = nr_node->routes[1];
283 nr_node->routes[1] = nr_node->routes[2];
284 nr_node->routes[2] = nr_route;
285 }
286 case 2:
287 if (nr_node->routes[1].quality > nr_node->routes[0].quality) {
288 switch (nr_node->which) {
289 case 0: nr_node->which = 1;
290 break;
291
292 case 1: nr_node->which = 0;
293 break;
294
295 default: break;
296 }
297 nr_route = nr_node->routes[0];
298 nr_node->routes[0] = nr_node->routes[1];
299 nr_node->routes[1] = nr_route;
300 }
301 case 1:
302 break;
303 }
304
305 for (i = 0; i < nr_node->count; i++) {
306 if (nr_node->routes[i].neighbour == nr_neigh) {
307 if (i < nr_node->which)
308 nr_node->which = i;
309 break;
310 }
311 }
312
313 nr_neigh_put(nr_neigh);
314 nr_node_unlock(nr_node);
315 nr_node_put(nr_node);
316 return 0;
317}
318
319static inline void __nr_remove_node(struct nr_node *nr_node)
320{
321 hlist_del_init(&nr_node->node_node);
322 nr_node_put(nr_node);
323}
324
325#define nr_remove_node_locked(__node) \
326 __nr_remove_node(__node)
327
328static void nr_remove_node(struct nr_node *nr_node)
329{
330 spin_lock_bh(&nr_node_list_lock);
331 __nr_remove_node(nr_node);
332 spin_unlock_bh(&nr_node_list_lock);
333}
334
335static inline void __nr_remove_neigh(struct nr_neigh *nr_neigh)
336{
337 hlist_del_init(&nr_neigh->neigh_node);
338 nr_neigh_put(nr_neigh);
339}
340
341#define nr_remove_neigh_locked(__neigh) \
342 __nr_remove_neigh(__neigh)
343
344static void nr_remove_neigh(struct nr_neigh *nr_neigh)
345{
346 spin_lock_bh(&nr_neigh_list_lock);
347 __nr_remove_neigh(nr_neigh);
348 spin_unlock_bh(&nr_neigh_list_lock);
349}
350
351/*
352 * "Delete" a node. Strictly speaking remove a route to a node. The node
353 * is only deleted if no routes are left to it.
354 */
355static int nr_del_node(ax25_address *callsign, ax25_address *neighbour, struct net_device *dev)
356{
357 struct nr_node *nr_node;
358 struct nr_neigh *nr_neigh;
359 int i;
360
361 nr_node = nr_node_get(callsign);
362
363 if (nr_node == NULL)
364 return -EINVAL;
365
366 nr_neigh = nr_neigh_get_dev(neighbour, dev);
367
368 if (nr_neigh == NULL) {
369 nr_node_put(nr_node);
370 return -EINVAL;
371 }
372
373 nr_node_lock(nr_node);
374 for (i = 0; i < nr_node->count; i++) {
375 if (nr_node->routes[i].neighbour == nr_neigh) {
376 nr_neigh->count--;
377 nr_neigh_put(nr_neigh);
378
379 if (nr_neigh->count == 0 && !nr_neigh->locked)
380 nr_remove_neigh(nr_neigh);
381 nr_neigh_put(nr_neigh);
382
383 nr_node->count--;
384
385 if (nr_node->count == 0) {
386 nr_remove_node(nr_node);
387 } else {
388 switch (i) {
389 case 0:
390 nr_node->routes[0] = nr_node->routes[1];
391 case 1:
392 nr_node->routes[1] = nr_node->routes[2];
393 case 2:
394 break;
395 }
396 nr_node_put(nr_node);
397 }
398 nr_node_unlock(nr_node);
399
400 return 0;
401 }
402 }
403 nr_neigh_put(nr_neigh);
404 nr_node_unlock(nr_node);
405 nr_node_put(nr_node);
406
407 return -EINVAL;
408}
409
410/*
411 * Lock a neighbour with a quality.
412 */
413static int __must_check nr_add_neigh(ax25_address *callsign,
414 ax25_digi *ax25_digi, struct net_device *dev, unsigned int quality)
415{
416 struct nr_neigh *nr_neigh;
417
418 nr_neigh = nr_neigh_get_dev(callsign, dev);
419 if (nr_neigh) {
420 nr_neigh->quality = quality;
421 nr_neigh->locked = 1;
422 nr_neigh_put(nr_neigh);
423 return 0;
424 }
425
426 if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL)
427 return -ENOMEM;
428
429 nr_neigh->callsign = *callsign;
430 nr_neigh->digipeat = NULL;
431 nr_neigh->ax25 = NULL;
432 nr_neigh->dev = dev;
433 nr_neigh->quality = quality;
434 nr_neigh->locked = 1;
435 nr_neigh->count = 0;
436 nr_neigh->number = nr_neigh_no++;
437 nr_neigh->failed = 0;
438 atomic_set(&nr_neigh->refcount, 1);
439
440 if (ax25_digi != NULL && ax25_digi->ndigi > 0) {
441 nr_neigh->digipeat = kmemdup(ax25_digi, sizeof(*ax25_digi),
442 GFP_KERNEL);
443 if (nr_neigh->digipeat == NULL) {
444 kfree(nr_neigh);
445 return -ENOMEM;
446 }
447 }
448
449 spin_lock_bh(&nr_neigh_list_lock);
450 hlist_add_head(&nr_neigh->neigh_node, &nr_neigh_list);
451 /* refcount is initialized at 1 */
452 spin_unlock_bh(&nr_neigh_list_lock);
453
454 return 0;
455}
456
457/*
458 * "Delete" a neighbour. The neighbour is only removed if the number
459 * of nodes that may use it is zero.
460 */
461static int nr_del_neigh(ax25_address *callsign, struct net_device *dev, unsigned int quality)
462{
463 struct nr_neigh *nr_neigh;
464
465 nr_neigh = nr_neigh_get_dev(callsign, dev);
466
467 if (nr_neigh == NULL) return -EINVAL;
468
469 nr_neigh->quality = quality;
470 nr_neigh->locked = 0;
471
472 if (nr_neigh->count == 0)
473 nr_remove_neigh(nr_neigh);
474 nr_neigh_put(nr_neigh);
475
476 return 0;
477}
478
479/*
480 * Decrement the obsolescence count by one. If a route is reduced to a
481 * count of zero, remove it. Also remove any unlocked neighbours with
482 * zero nodes routing via it.
483 */
484static int nr_dec_obs(void)
485{
486 struct nr_neigh *nr_neigh;
487 struct nr_node *s;
488 struct hlist_node *node, *nodet;
489 int i;
490
491 spin_lock_bh(&nr_node_list_lock);
492 nr_node_for_each_safe(s, node, nodet, &nr_node_list) {
493 nr_node_lock(s);
494 for (i = 0; i < s->count; i++) {
495 switch (s->routes[i].obs_count) {
496 case 0: /* A locked entry */
497 break;
498
499 case 1: /* From 1 -> 0 */
500 nr_neigh = s->routes[i].neighbour;
501
502 nr_neigh->count--;
503 nr_neigh_put(nr_neigh);
504
505 if (nr_neigh->count == 0 && !nr_neigh->locked)
506 nr_remove_neigh(nr_neigh);
507
508 s->count--;
509
510 switch (i) {
511 case 0:
512 s->routes[0] = s->routes[1];
513 /* Fallthrough */
514 case 1:
515 s->routes[1] = s->routes[2];
516 case 2:
517 break;
518 }
519 break;
520
521 default:
522 s->routes[i].obs_count--;
523 break;
524
525 }
526 }
527
528 if (s->count <= 0)
529 nr_remove_node_locked(s);
530 nr_node_unlock(s);
531 }
532 spin_unlock_bh(&nr_node_list_lock);
533
534 return 0;
535}
536
537/*
538 * A device has been removed. Remove its routes and neighbours.
539 */
540void nr_rt_device_down(struct net_device *dev)
541{
542 struct nr_neigh *s;
543 struct hlist_node *node, *nodet, *node2, *node2t;
544 struct nr_node *t;
545 int i;
546
547 spin_lock_bh(&nr_neigh_list_lock);
548 nr_neigh_for_each_safe(s, node, nodet, &nr_neigh_list) {
549 if (s->dev == dev) {
550 spin_lock_bh(&nr_node_list_lock);
551 nr_node_for_each_safe(t, node2, node2t, &nr_node_list) {
552 nr_node_lock(t);
553 for (i = 0; i < t->count; i++) {
554 if (t->routes[i].neighbour == s) {
555 t->count--;
556
557 switch (i) {
558 case 0:
559 t->routes[0] = t->routes[1];
560 case 1:
561 t->routes[1] = t->routes[2];
562 case 2:
563 break;
564 }
565 }
566 }
567
568 if (t->count <= 0)
569 nr_remove_node_locked(t);
570 nr_node_unlock(t);
571 }
572 spin_unlock_bh(&nr_node_list_lock);
573
574 nr_remove_neigh_locked(s);
575 }
576 }
577 spin_unlock_bh(&nr_neigh_list_lock);
578}
579
580/*
581 * Check that the device given is a valid AX.25 interface that is "up".
582 * Or a valid ethernet interface with an AX.25 callsign binding.
583 */
584static struct net_device *nr_ax25_dev_get(char *devname)
585{
586 struct net_device *dev;
587
588 if ((dev = dev_get_by_name(&init_net, devname)) == NULL)
589 return NULL;
590
591 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_AX25)
592 return dev;
593
594 dev_put(dev);
595 return NULL;
596}
597
598/*
599 * Find the first active NET/ROM device, usually "nr0".
600 */
601struct net_device *nr_dev_first(void)
602{
603 struct net_device *dev, *first = NULL;
604
605 rcu_read_lock();
606 for_each_netdev_rcu(&init_net, dev) {
607 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM)
608 if (first == NULL || strncmp(dev->name, first->name, 3) < 0)
609 first = dev;
610 }
611 if (first)
612 dev_hold(first);
613 rcu_read_unlock();
614
615 return first;
616}
617
618/*
619 * Find the NET/ROM device for the given callsign.
620 */
621struct net_device *nr_dev_get(ax25_address *addr)
622{
623 struct net_device *dev;
624
625 rcu_read_lock();
626 for_each_netdev_rcu(&init_net, dev) {
627 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM &&
628 ax25cmp(addr, (ax25_address *)dev->dev_addr) == 0) {
629 dev_hold(dev);
630 goto out;
631 }
632 }
633 dev = NULL;
634out:
635 rcu_read_unlock();
636 return dev;
637}
638
639static ax25_digi *nr_call_to_digi(ax25_digi *digi, int ndigis,
640 ax25_address *digipeaters)
641{
642 int i;
643
644 if (ndigis == 0)
645 return NULL;
646
647 for (i = 0; i < ndigis; i++) {
648 digi->calls[i] = digipeaters[i];
649 digi->repeated[i] = 0;
650 }
651
652 digi->ndigi = ndigis;
653 digi->lastrepeat = -1;
654
655 return digi;
656}
657
658/*
659 * Handle the ioctls that control the routing functions.
660 */
661int nr_rt_ioctl(unsigned int cmd, void __user *arg)
662{
663 struct nr_route_struct nr_route;
664 struct net_device *dev;
665 ax25_digi digi;
666 int ret;
667
668 switch (cmd) {
669 case SIOCADDRT:
670 if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct)))
671 return -EFAULT;
672 if (nr_route.ndigis > AX25_MAX_DIGIS)
673 return -EINVAL;
674 if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL)
675 return -EINVAL;
676 switch (nr_route.type) {
677 case NETROM_NODE:
678 if (strnlen(nr_route.mnemonic, 7) == 7) {
679 ret = -EINVAL;
680 break;
681 }
682
683 ret = nr_add_node(&nr_route.callsign,
684 nr_route.mnemonic,
685 &nr_route.neighbour,
686 nr_call_to_digi(&digi, nr_route.ndigis,
687 nr_route.digipeaters),
688 dev, nr_route.quality,
689 nr_route.obs_count);
690 break;
691 case NETROM_NEIGH:
692 ret = nr_add_neigh(&nr_route.callsign,
693 nr_call_to_digi(&digi, nr_route.ndigis,
694 nr_route.digipeaters),
695 dev, nr_route.quality);
696 break;
697 default:
698 ret = -EINVAL;
699 }
700 dev_put(dev);
701 return ret;
702
703 case SIOCDELRT:
704 if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct)))
705 return -EFAULT;
706 if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL)
707 return -EINVAL;
708 switch (nr_route.type) {
709 case NETROM_NODE:
710 ret = nr_del_node(&nr_route.callsign,
711 &nr_route.neighbour, dev);
712 break;
713 case NETROM_NEIGH:
714 ret = nr_del_neigh(&nr_route.callsign,
715 dev, nr_route.quality);
716 break;
717 default:
718 ret = -EINVAL;
719 }
720 dev_put(dev);
721 return ret;
722
723 case SIOCNRDECOBS:
724 return nr_dec_obs();
725
726 default:
727 return -EINVAL;
728 }
729
730 return 0;
731}
732
733/*
734 * A level 2 link has timed out, therefore it appears to be a poor link,
735 * then don't use that neighbour until it is reset.
736 */
737void nr_link_failed(ax25_cb *ax25, int reason)
738{
739 struct nr_neigh *s, *nr_neigh = NULL;
740 struct hlist_node *node;
741 struct nr_node *nr_node = NULL;
742
743 spin_lock_bh(&nr_neigh_list_lock);
744 nr_neigh_for_each(s, node, &nr_neigh_list) {
745 if (s->ax25 == ax25) {
746 nr_neigh_hold(s);
747 nr_neigh = s;
748 break;
749 }
750 }
751 spin_unlock_bh(&nr_neigh_list_lock);
752
753 if (nr_neigh == NULL)
754 return;
755
756 nr_neigh->ax25 = NULL;
757 ax25_cb_put(ax25);
758
759 if (++nr_neigh->failed < sysctl_netrom_link_fails_count) {
760 nr_neigh_put(nr_neigh);
761 return;
762 }
763 spin_lock_bh(&nr_node_list_lock);
764 nr_node_for_each(nr_node, node, &nr_node_list) {
765 nr_node_lock(nr_node);
766 if (nr_node->which < nr_node->count &&
767 nr_node->routes[nr_node->which].neighbour == nr_neigh)
768 nr_node->which++;
769 nr_node_unlock(nr_node);
770 }
771 spin_unlock_bh(&nr_node_list_lock);
772 nr_neigh_put(nr_neigh);
773}
774
775/*
776 * Route a frame to an appropriate AX.25 connection. A NULL ax25_cb
777 * indicates an internally generated frame.
778 */
779int nr_route_frame(struct sk_buff *skb, ax25_cb *ax25)
780{
781 ax25_address *nr_src, *nr_dest;
782 struct nr_neigh *nr_neigh;
783 struct nr_node *nr_node;
784 struct net_device *dev;
785 unsigned char *dptr;
786 ax25_cb *ax25s;
787 int ret;
788 struct sk_buff *skbn;
789
790
791 nr_src = (ax25_address *)(skb->data + 0);
792 nr_dest = (ax25_address *)(skb->data + 7);
793
794 if (ax25 != NULL) {
795 ret = nr_add_node(nr_src, "", &ax25->dest_addr, ax25->digipeat,
796 ax25->ax25_dev->dev, 0,
797 sysctl_netrom_obsolescence_count_initialiser);
798 if (ret)
799 return ret;
800 }
801
802 if ((dev = nr_dev_get(nr_dest)) != NULL) { /* Its for me */
803 if (ax25 == NULL) /* Its from me */
804 ret = nr_loopback_queue(skb);
805 else
806 ret = nr_rx_frame(skb, dev);
807 dev_put(dev);
808 return ret;
809 }
810
811 if (!sysctl_netrom_routing_control && ax25 != NULL)
812 return 0;
813
814 /* Its Time-To-Live has expired */
815 if (skb->data[14] == 1) {
816 return 0;
817 }
818
819 nr_node = nr_node_get(nr_dest);
820 if (nr_node == NULL)
821 return 0;
822 nr_node_lock(nr_node);
823
824 if (nr_node->which >= nr_node->count) {
825 nr_node_unlock(nr_node);
826 nr_node_put(nr_node);
827 return 0;
828 }
829
830 nr_neigh = nr_node->routes[nr_node->which].neighbour;
831
832 if ((dev = nr_dev_first()) == NULL) {
833 nr_node_unlock(nr_node);
834 nr_node_put(nr_node);
835 return 0;
836 }
837
838 /* We are going to change the netrom headers so we should get our
839 own skb, we also did not know until now how much header space
840 we had to reserve... - RXQ */
841 if ((skbn=skb_copy_expand(skb, dev->hard_header_len, 0, GFP_ATOMIC)) == NULL) {
842 nr_node_unlock(nr_node);
843 nr_node_put(nr_node);
844 dev_put(dev);
845 return 0;
846 }
847 kfree_skb(skb);
848 skb=skbn;
849 skb->data[14]--;
850
851 dptr = skb_push(skb, 1);
852 *dptr = AX25_P_NETROM;
853
854 ax25s = nr_neigh->ax25;
855 nr_neigh->ax25 = ax25_send_frame(skb, 256,
856 (ax25_address *)dev->dev_addr,
857 &nr_neigh->callsign,
858 nr_neigh->digipeat, nr_neigh->dev);
859 if (ax25s)
860 ax25_cb_put(ax25s);
861
862 dev_put(dev);
863 ret = (nr_neigh->ax25 != NULL);
864 nr_node_unlock(nr_node);
865 nr_node_put(nr_node);
866
867 return ret;
868}
869
870#ifdef CONFIG_PROC_FS
871
872static void *nr_node_start(struct seq_file *seq, loff_t *pos)
873{
874 spin_lock_bh(&nr_node_list_lock);
875 return seq_hlist_start_head(&nr_node_list, *pos);
876}
877
878static void *nr_node_next(struct seq_file *seq, void *v, loff_t *pos)
879{
880 return seq_hlist_next(v, &nr_node_list, pos);
881}
882
883static void nr_node_stop(struct seq_file *seq, void *v)
884{
885 spin_unlock_bh(&nr_node_list_lock);
886}
887
888static int nr_node_show(struct seq_file *seq, void *v)
889{
890 char buf[11];
891 int i;
892
893 if (v == SEQ_START_TOKEN)
894 seq_puts(seq,
895 "callsign mnemonic w n qual obs neigh qual obs neigh qual obs neigh\n");
896 else {
897 struct nr_node *nr_node = hlist_entry(v, struct nr_node,
898 node_node);
899
900 nr_node_lock(nr_node);
901 seq_printf(seq, "%-9s %-7s %d %d",
902 ax2asc(buf, &nr_node->callsign),
903 (nr_node->mnemonic[0] == '\0') ? "*" : nr_node->mnemonic,
904 nr_node->which + 1,
905 nr_node->count);
906
907 for (i = 0; i < nr_node->count; i++) {
908 seq_printf(seq, " %3d %d %05d",
909 nr_node->routes[i].quality,
910 nr_node->routes[i].obs_count,
911 nr_node->routes[i].neighbour->number);
912 }
913 nr_node_unlock(nr_node);
914
915 seq_puts(seq, "\n");
916 }
917 return 0;
918}
919
920static const struct seq_operations nr_node_seqops = {
921 .start = nr_node_start,
922 .next = nr_node_next,
923 .stop = nr_node_stop,
924 .show = nr_node_show,
925};
926
927static int nr_node_info_open(struct inode *inode, struct file *file)
928{
929 return seq_open(file, &nr_node_seqops);
930}
931
932const struct file_operations nr_nodes_fops = {
933 .owner = THIS_MODULE,
934 .open = nr_node_info_open,
935 .read = seq_read,
936 .llseek = seq_lseek,
937 .release = seq_release,
938};
939
940static void *nr_neigh_start(struct seq_file *seq, loff_t *pos)
941{
942 spin_lock_bh(&nr_neigh_list_lock);
943 return seq_hlist_start_head(&nr_neigh_list, *pos);
944}
945
946static void *nr_neigh_next(struct seq_file *seq, void *v, loff_t *pos)
947{
948 return seq_hlist_next(v, &nr_neigh_list, pos);
949}
950
951static void nr_neigh_stop(struct seq_file *seq, void *v)
952{
953 spin_unlock_bh(&nr_neigh_list_lock);
954}
955
956static int nr_neigh_show(struct seq_file *seq, void *v)
957{
958 char buf[11];
959 int i;
960
961 if (v == SEQ_START_TOKEN)
962 seq_puts(seq, "addr callsign dev qual lock count failed digipeaters\n");
963 else {
964 struct nr_neigh *nr_neigh;
965
966 nr_neigh = hlist_entry(v, struct nr_neigh, neigh_node);
967 seq_printf(seq, "%05d %-9s %-4s %3d %d %3d %3d",
968 nr_neigh->number,
969 ax2asc(buf, &nr_neigh->callsign),
970 nr_neigh->dev ? nr_neigh->dev->name : "???",
971 nr_neigh->quality,
972 nr_neigh->locked,
973 nr_neigh->count,
974 nr_neigh->failed);
975
976 if (nr_neigh->digipeat != NULL) {
977 for (i = 0; i < nr_neigh->digipeat->ndigi; i++)
978 seq_printf(seq, " %s",
979 ax2asc(buf, &nr_neigh->digipeat->calls[i]));
980 }
981
982 seq_puts(seq, "\n");
983 }
984 return 0;
985}
986
987static const struct seq_operations nr_neigh_seqops = {
988 .start = nr_neigh_start,
989 .next = nr_neigh_next,
990 .stop = nr_neigh_stop,
991 .show = nr_neigh_show,
992};
993
994static int nr_neigh_info_open(struct inode *inode, struct file *file)
995{
996 return seq_open(file, &nr_neigh_seqops);
997}
998
999const struct file_operations nr_neigh_fops = {
1000 .owner = THIS_MODULE,
1001 .open = nr_neigh_info_open,
1002 .read = seq_read,
1003 .llseek = seq_lseek,
1004 .release = seq_release,
1005};
1006
1007#endif
1008
1009/*
1010 * Free all memory associated with the nodes and routes lists.
1011 */
1012void __exit nr_rt_free(void)
1013{
1014 struct nr_neigh *s = NULL;
1015 struct nr_node *t = NULL;
1016 struct hlist_node *node, *nodet;
1017
1018 spin_lock_bh(&nr_neigh_list_lock);
1019 spin_lock_bh(&nr_node_list_lock);
1020 nr_node_for_each_safe(t, node, nodet, &nr_node_list) {
1021 nr_node_lock(t);
1022 nr_remove_node_locked(t);
1023 nr_node_unlock(t);
1024 }
1025 nr_neigh_for_each_safe(s, node, nodet, &nr_neigh_list) {
1026 while(s->count) {
1027 s->count--;
1028 nr_neigh_put(s);
1029 }
1030 nr_remove_neigh_locked(s);
1031 }
1032 spin_unlock_bh(&nr_node_list_lock);
1033 spin_unlock_bh(&nr_neigh_list_lock);
1034}