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