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