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