Merge tag 'media/v6.1-4' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab...
[platform/kernel/linux-starfive.git] / net / rose / rose_route.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *
4  * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
5  * Copyright (C) Terry Dawson VK2KTJ (terry@animats.net)
6  */
7 #include <linux/errno.h>
8 #include <linux/types.h>
9 #include <linux/socket.h>
10 #include <linux/in.h>
11 #include <linux/kernel.h>
12 #include <linux/timer.h>
13 #include <linux/string.h>
14 #include <linux/sockios.h>
15 #include <linux/net.h>
16 #include <linux/slab.h>
17 #include <net/ax25.h>
18 #include <linux/inet.h>
19 #include <linux/netdevice.h>
20 #include <net/arp.h>
21 #include <linux/if_arp.h>
22 #include <linux/skbuff.h>
23 #include <net/sock.h>
24 #include <net/tcp_states.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 <net/rose.h>
33 #include <linux/seq_file.h>
34 #include <linux/export.h>
35
36 static unsigned int rose_neigh_no = 1;
37
38 static struct rose_node  *rose_node_list;
39 static DEFINE_SPINLOCK(rose_node_list_lock);
40 static struct rose_neigh *rose_neigh_list;
41 static DEFINE_SPINLOCK(rose_neigh_list_lock);
42 static struct rose_route *rose_route_list;
43 static DEFINE_SPINLOCK(rose_route_list_lock);
44
45 struct rose_neigh *rose_loopback_neigh;
46
47 /*
48  *      Add a new route to a node, and in the process add the node and the
49  *      neighbour if it is new.
50  */
51 static int __must_check rose_add_node(struct rose_route_struct *rose_route,
52         struct net_device *dev)
53 {
54         struct rose_node  *rose_node, *rose_tmpn, *rose_tmpp;
55         struct rose_neigh *rose_neigh;
56         int i, res = 0;
57
58         spin_lock_bh(&rose_node_list_lock);
59         spin_lock_bh(&rose_neigh_list_lock);
60
61         rose_node = rose_node_list;
62         while (rose_node != NULL) {
63                 if ((rose_node->mask == rose_route->mask) &&
64                     (rosecmpm(&rose_route->address, &rose_node->address,
65                               rose_route->mask) == 0))
66                         break;
67                 rose_node = rose_node->next;
68         }
69
70         if (rose_node != NULL && rose_node->loopback) {
71                 res = -EINVAL;
72                 goto out;
73         }
74
75         rose_neigh = rose_neigh_list;
76         while (rose_neigh != NULL) {
77                 if (ax25cmp(&rose_route->neighbour,
78                             &rose_neigh->callsign) == 0 &&
79                     rose_neigh->dev == dev)
80                         break;
81                 rose_neigh = rose_neigh->next;
82         }
83
84         if (rose_neigh == NULL) {
85                 rose_neigh = kmalloc(sizeof(*rose_neigh), GFP_ATOMIC);
86                 if (rose_neigh == NULL) {
87                         res = -ENOMEM;
88                         goto out;
89                 }
90
91                 rose_neigh->callsign  = rose_route->neighbour;
92                 rose_neigh->digipeat  = NULL;
93                 rose_neigh->ax25      = NULL;
94                 rose_neigh->dev       = dev;
95                 rose_neigh->count     = 0;
96                 rose_neigh->use       = 0;
97                 rose_neigh->dce_mode  = 0;
98                 rose_neigh->loopback  = 0;
99                 rose_neigh->number    = rose_neigh_no++;
100                 rose_neigh->restarted = 0;
101
102                 skb_queue_head_init(&rose_neigh->queue);
103
104                 timer_setup(&rose_neigh->ftimer, NULL, 0);
105                 timer_setup(&rose_neigh->t0timer, NULL, 0);
106
107                 if (rose_route->ndigis != 0) {
108                         rose_neigh->digipeat =
109                                 kmalloc(sizeof(ax25_digi), GFP_ATOMIC);
110                         if (rose_neigh->digipeat == NULL) {
111                                 kfree(rose_neigh);
112                                 res = -ENOMEM;
113                                 goto out;
114                         }
115
116                         rose_neigh->digipeat->ndigi      = rose_route->ndigis;
117                         rose_neigh->digipeat->lastrepeat = -1;
118
119                         for (i = 0; i < rose_route->ndigis; i++) {
120                                 rose_neigh->digipeat->calls[i]    =
121                                         rose_route->digipeaters[i];
122                                 rose_neigh->digipeat->repeated[i] = 0;
123                         }
124                 }
125
126                 rose_neigh->next = rose_neigh_list;
127                 rose_neigh_list  = rose_neigh;
128         }
129
130         /*
131          * This is a new node to be inserted into the list. Find where it needs
132          * to be inserted into the list, and insert it. We want to be sure
133          * to order the list in descending order of mask size to ensure that
134          * later when we are searching this list the first match will be the
135          * best match.
136          */
137         if (rose_node == NULL) {
138                 rose_tmpn = rose_node_list;
139                 rose_tmpp = NULL;
140
141                 while (rose_tmpn != NULL) {
142                         if (rose_tmpn->mask > rose_route->mask) {
143                                 rose_tmpp = rose_tmpn;
144                                 rose_tmpn = rose_tmpn->next;
145                         } else {
146                                 break;
147                         }
148                 }
149
150                 /* create new node */
151                 rose_node = kmalloc(sizeof(*rose_node), GFP_ATOMIC);
152                 if (rose_node == NULL) {
153                         res = -ENOMEM;
154                         goto out;
155                 }
156
157                 rose_node->address      = rose_route->address;
158                 rose_node->mask         = rose_route->mask;
159                 rose_node->count        = 1;
160                 rose_node->loopback     = 0;
161                 rose_node->neighbour[0] = rose_neigh;
162
163                 if (rose_tmpn == NULL) {
164                         if (rose_tmpp == NULL) {        /* Empty list */
165                                 rose_node_list  = rose_node;
166                                 rose_node->next = NULL;
167                         } else {
168                                 rose_tmpp->next = rose_node;
169                                 rose_node->next = NULL;
170                         }
171                 } else {
172                         if (rose_tmpp == NULL) {        /* 1st node */
173                                 rose_node->next = rose_node_list;
174                                 rose_node_list  = rose_node;
175                         } else {
176                                 rose_tmpp->next = rose_node;
177                                 rose_node->next = rose_tmpn;
178                         }
179                 }
180                 rose_neigh->count++;
181
182                 goto out;
183         }
184
185         /* We have space, slot it in */
186         if (rose_node->count < 3) {
187                 rose_node->neighbour[rose_node->count] = rose_neigh;
188                 rose_node->count++;
189                 rose_neigh->count++;
190         }
191
192 out:
193         spin_unlock_bh(&rose_neigh_list_lock);
194         spin_unlock_bh(&rose_node_list_lock);
195
196         return res;
197 }
198
199 /*
200  * Caller is holding rose_node_list_lock.
201  */
202 static void rose_remove_node(struct rose_node *rose_node)
203 {
204         struct rose_node *s;
205
206         if ((s = rose_node_list) == rose_node) {
207                 rose_node_list = rose_node->next;
208                 kfree(rose_node);
209                 return;
210         }
211
212         while (s != NULL && s->next != NULL) {
213                 if (s->next == rose_node) {
214                         s->next = rose_node->next;
215                         kfree(rose_node);
216                         return;
217                 }
218
219                 s = s->next;
220         }
221 }
222
223 /*
224  * Caller is holding rose_neigh_list_lock.
225  */
226 static void rose_remove_neigh(struct rose_neigh *rose_neigh)
227 {
228         struct rose_neigh *s;
229
230         del_timer_sync(&rose_neigh->ftimer);
231         del_timer_sync(&rose_neigh->t0timer);
232
233         skb_queue_purge(&rose_neigh->queue);
234
235         if ((s = rose_neigh_list) == rose_neigh) {
236                 rose_neigh_list = rose_neigh->next;
237                 if (rose_neigh->ax25)
238                         ax25_cb_put(rose_neigh->ax25);
239                 kfree(rose_neigh->digipeat);
240                 kfree(rose_neigh);
241                 return;
242         }
243
244         while (s != NULL && s->next != NULL) {
245                 if (s->next == rose_neigh) {
246                         s->next = rose_neigh->next;
247                         if (rose_neigh->ax25)
248                                 ax25_cb_put(rose_neigh->ax25);
249                         kfree(rose_neigh->digipeat);
250                         kfree(rose_neigh);
251                         return;
252                 }
253
254                 s = s->next;
255         }
256 }
257
258 /*
259  * Caller is holding rose_route_list_lock.
260  */
261 static void rose_remove_route(struct rose_route *rose_route)
262 {
263         struct rose_route *s;
264
265         if (rose_route->neigh1 != NULL)
266                 rose_route->neigh1->use--;
267
268         if (rose_route->neigh2 != NULL)
269                 rose_route->neigh2->use--;
270
271         if ((s = rose_route_list) == rose_route) {
272                 rose_route_list = rose_route->next;
273                 kfree(rose_route);
274                 return;
275         }
276
277         while (s != NULL && s->next != NULL) {
278                 if (s->next == rose_route) {
279                         s->next = rose_route->next;
280                         kfree(rose_route);
281                         return;
282                 }
283
284                 s = s->next;
285         }
286 }
287
288 /*
289  *      "Delete" a node. Strictly speaking remove a route to a node. The node
290  *      is only deleted if no routes are left to it.
291  */
292 static int rose_del_node(struct rose_route_struct *rose_route,
293         struct net_device *dev)
294 {
295         struct rose_node  *rose_node;
296         struct rose_neigh *rose_neigh;
297         int i, err = 0;
298
299         spin_lock_bh(&rose_node_list_lock);
300         spin_lock_bh(&rose_neigh_list_lock);
301
302         rose_node = rose_node_list;
303         while (rose_node != NULL) {
304                 if ((rose_node->mask == rose_route->mask) &&
305                     (rosecmpm(&rose_route->address, &rose_node->address,
306                               rose_route->mask) == 0))
307                         break;
308                 rose_node = rose_node->next;
309         }
310
311         if (rose_node == NULL || rose_node->loopback) {
312                 err = -EINVAL;
313                 goto out;
314         }
315
316         rose_neigh = rose_neigh_list;
317         while (rose_neigh != NULL) {
318                 if (ax25cmp(&rose_route->neighbour,
319                             &rose_neigh->callsign) == 0 &&
320                     rose_neigh->dev == dev)
321                         break;
322                 rose_neigh = rose_neigh->next;
323         }
324
325         if (rose_neigh == NULL) {
326                 err = -EINVAL;
327                 goto out;
328         }
329
330         for (i = 0; i < rose_node->count; i++) {
331                 if (rose_node->neighbour[i] == rose_neigh) {
332                         rose_neigh->count--;
333
334                         if (rose_neigh->count == 0 && rose_neigh->use == 0)
335                                 rose_remove_neigh(rose_neigh);
336
337                         rose_node->count--;
338
339                         if (rose_node->count == 0) {
340                                 rose_remove_node(rose_node);
341                         } else {
342                                 switch (i) {
343                                 case 0:
344                                         rose_node->neighbour[0] =
345                                                 rose_node->neighbour[1];
346                                         fallthrough;
347                                 case 1:
348                                         rose_node->neighbour[1] =
349                                                 rose_node->neighbour[2];
350                                         break;
351                                 case 2:
352                                         break;
353                                 }
354                         }
355                         goto out;
356                 }
357         }
358         err = -EINVAL;
359
360 out:
361         spin_unlock_bh(&rose_neigh_list_lock);
362         spin_unlock_bh(&rose_node_list_lock);
363
364         return err;
365 }
366
367 /*
368  *      Add the loopback neighbour.
369  */
370 void rose_add_loopback_neigh(void)
371 {
372         struct rose_neigh *sn;
373
374         rose_loopback_neigh = kmalloc(sizeof(struct rose_neigh), GFP_KERNEL);
375         if (!rose_loopback_neigh)
376                 return;
377         sn = rose_loopback_neigh;
378
379         sn->callsign  = null_ax25_address;
380         sn->digipeat  = NULL;
381         sn->ax25      = NULL;
382         sn->dev       = NULL;
383         sn->count     = 0;
384         sn->use       = 0;
385         sn->dce_mode  = 1;
386         sn->loopback  = 1;
387         sn->number    = rose_neigh_no++;
388         sn->restarted = 1;
389
390         skb_queue_head_init(&sn->queue);
391
392         timer_setup(&sn->ftimer, NULL, 0);
393         timer_setup(&sn->t0timer, NULL, 0);
394
395         spin_lock_bh(&rose_neigh_list_lock);
396         sn->next = rose_neigh_list;
397         rose_neigh_list           = sn;
398         spin_unlock_bh(&rose_neigh_list_lock);
399 }
400
401 /*
402  *      Add a loopback node.
403  */
404 int rose_add_loopback_node(const rose_address *address)
405 {
406         struct rose_node *rose_node;
407         int err = 0;
408
409         spin_lock_bh(&rose_node_list_lock);
410
411         rose_node = rose_node_list;
412         while (rose_node != NULL) {
413                 if ((rose_node->mask == 10) &&
414                      (rosecmpm(address, &rose_node->address, 10) == 0) &&
415                      rose_node->loopback)
416                         break;
417                 rose_node = rose_node->next;
418         }
419
420         if (rose_node != NULL)
421                 goto out;
422
423         if ((rose_node = kmalloc(sizeof(*rose_node), GFP_ATOMIC)) == NULL) {
424                 err = -ENOMEM;
425                 goto out;
426         }
427
428         rose_node->address      = *address;
429         rose_node->mask         = 10;
430         rose_node->count        = 1;
431         rose_node->loopback     = 1;
432         rose_node->neighbour[0] = rose_loopback_neigh;
433
434         /* Insert at the head of list. Address is always mask=10 */
435         rose_node->next = rose_node_list;
436         rose_node_list  = rose_node;
437
438         rose_loopback_neigh->count++;
439
440 out:
441         spin_unlock_bh(&rose_node_list_lock);
442
443         return err;
444 }
445
446 /*
447  *      Delete a loopback node.
448  */
449 void rose_del_loopback_node(const rose_address *address)
450 {
451         struct rose_node *rose_node;
452
453         spin_lock_bh(&rose_node_list_lock);
454
455         rose_node = rose_node_list;
456         while (rose_node != NULL) {
457                 if ((rose_node->mask == 10) &&
458                     (rosecmpm(address, &rose_node->address, 10) == 0) &&
459                     rose_node->loopback)
460                         break;
461                 rose_node = rose_node->next;
462         }
463
464         if (rose_node == NULL)
465                 goto out;
466
467         rose_remove_node(rose_node);
468
469         rose_loopback_neigh->count--;
470
471 out:
472         spin_unlock_bh(&rose_node_list_lock);
473 }
474
475 /*
476  *      A device has been removed. Remove its routes and neighbours.
477  */
478 void rose_rt_device_down(struct net_device *dev)
479 {
480         struct rose_neigh *s, *rose_neigh;
481         struct rose_node  *t, *rose_node;
482         int i;
483
484         spin_lock_bh(&rose_node_list_lock);
485         spin_lock_bh(&rose_neigh_list_lock);
486         rose_neigh = rose_neigh_list;
487         while (rose_neigh != NULL) {
488                 s          = rose_neigh;
489                 rose_neigh = rose_neigh->next;
490
491                 if (s->dev != dev)
492                         continue;
493
494                 rose_node = rose_node_list;
495
496                 while (rose_node != NULL) {
497                         t         = rose_node;
498                         rose_node = rose_node->next;
499
500                         for (i = 0; i < t->count; i++) {
501                                 if (t->neighbour[i] != s)
502                                         continue;
503
504                                 t->count--;
505
506                                 switch (i) {
507                                 case 0:
508                                         t->neighbour[0] = t->neighbour[1];
509                                         fallthrough;
510                                 case 1:
511                                         t->neighbour[1] = t->neighbour[2];
512                                         break;
513                                 case 2:
514                                         break;
515                                 }
516                         }
517
518                         if (t->count <= 0)
519                                 rose_remove_node(t);
520                 }
521
522                 rose_remove_neigh(s);
523         }
524         spin_unlock_bh(&rose_neigh_list_lock);
525         spin_unlock_bh(&rose_node_list_lock);
526 }
527
528 #if 0 /* Currently unused */
529 /*
530  *      A device has been removed. Remove its links.
531  */
532 void rose_route_device_down(struct net_device *dev)
533 {
534         struct rose_route *s, *rose_route;
535
536         spin_lock_bh(&rose_route_list_lock);
537         rose_route = rose_route_list;
538         while (rose_route != NULL) {
539                 s          = rose_route;
540                 rose_route = rose_route->next;
541
542                 if (s->neigh1->dev == dev || s->neigh2->dev == dev)
543                         rose_remove_route(s);
544         }
545         spin_unlock_bh(&rose_route_list_lock);
546 }
547 #endif
548
549 /*
550  *      Clear all nodes and neighbours out, except for neighbours with
551  *      active connections going through them.
552  *  Do not clear loopback neighbour and nodes.
553  */
554 static int rose_clear_routes(void)
555 {
556         struct rose_neigh *s, *rose_neigh;
557         struct rose_node  *t, *rose_node;
558
559         spin_lock_bh(&rose_node_list_lock);
560         spin_lock_bh(&rose_neigh_list_lock);
561
562         rose_neigh = rose_neigh_list;
563         rose_node  = rose_node_list;
564
565         while (rose_node != NULL) {
566                 t         = rose_node;
567                 rose_node = rose_node->next;
568                 if (!t->loopback)
569                         rose_remove_node(t);
570         }
571
572         while (rose_neigh != NULL) {
573                 s          = rose_neigh;
574                 rose_neigh = rose_neigh->next;
575
576                 if (s->use == 0 && !s->loopback) {
577                         s->count = 0;
578                         rose_remove_neigh(s);
579                 }
580         }
581
582         spin_unlock_bh(&rose_neigh_list_lock);
583         spin_unlock_bh(&rose_node_list_lock);
584
585         return 0;
586 }
587
588 /*
589  *      Check that the device given is a valid AX.25 interface that is "up".
590  *      called with RTNL
591  */
592 static struct net_device *rose_ax25_dev_find(char *devname)
593 {
594         struct net_device *dev;
595
596         if ((dev = __dev_get_by_name(&init_net, devname)) == NULL)
597                 return NULL;
598
599         if ((dev->flags & IFF_UP) && dev->type == ARPHRD_AX25)
600                 return dev;
601
602         return NULL;
603 }
604
605 /*
606  *      Find the first active ROSE device, usually "rose0".
607  */
608 struct net_device *rose_dev_first(void)
609 {
610         struct net_device *dev, *first = NULL;
611
612         rcu_read_lock();
613         for_each_netdev_rcu(&init_net, dev) {
614                 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_ROSE)
615                         if (first == NULL || strncmp(dev->name, first->name, 3) < 0)
616                                 first = dev;
617         }
618         if (first)
619                 dev_hold(first);
620         rcu_read_unlock();
621
622         return first;
623 }
624
625 /*
626  *      Find the ROSE device for the given address.
627  */
628 struct net_device *rose_dev_get(rose_address *addr)
629 {
630         struct net_device *dev;
631
632         rcu_read_lock();
633         for_each_netdev_rcu(&init_net, dev) {
634                 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_ROSE &&
635                     rosecmp(addr, (const rose_address *)dev->dev_addr) == 0) {
636                         dev_hold(dev);
637                         goto out;
638                 }
639         }
640         dev = NULL;
641 out:
642         rcu_read_unlock();
643         return dev;
644 }
645
646 static int rose_dev_exists(rose_address *addr)
647 {
648         struct net_device *dev;
649
650         rcu_read_lock();
651         for_each_netdev_rcu(&init_net, dev) {
652                 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_ROSE &&
653                     rosecmp(addr, (const rose_address *)dev->dev_addr) == 0)
654                         goto out;
655         }
656         dev = NULL;
657 out:
658         rcu_read_unlock();
659         return dev != NULL;
660 }
661
662
663
664
665 struct rose_route *rose_route_free_lci(unsigned int lci, struct rose_neigh *neigh)
666 {
667         struct rose_route *rose_route;
668
669         for (rose_route = rose_route_list; rose_route != NULL; rose_route = rose_route->next)
670                 if ((rose_route->neigh1 == neigh && rose_route->lci1 == lci) ||
671                     (rose_route->neigh2 == neigh && rose_route->lci2 == lci))
672                         return rose_route;
673
674         return NULL;
675 }
676
677 /*
678  *      Find a neighbour or a route given a ROSE address.
679  */
680 struct rose_neigh *rose_get_neigh(rose_address *addr, unsigned char *cause,
681         unsigned char *diagnostic, int route_frame)
682 {
683         struct rose_neigh *res = NULL;
684         struct rose_node *node;
685         int failed = 0;
686         int i;
687
688         if (!route_frame) spin_lock_bh(&rose_node_list_lock);
689         for (node = rose_node_list; node != NULL; node = node->next) {
690                 if (rosecmpm(addr, &node->address, node->mask) == 0) {
691                         for (i = 0; i < node->count; i++) {
692                                 if (node->neighbour[i]->restarted) {
693                                         res = node->neighbour[i];
694                                         goto out;
695                                 }
696                         }
697                 }
698         }
699         if (!route_frame) { /* connect request */
700                 for (node = rose_node_list; node != NULL; node = node->next) {
701                         if (rosecmpm(addr, &node->address, node->mask) == 0) {
702                                 for (i = 0; i < node->count; i++) {
703                                         if (!rose_ftimer_running(node->neighbour[i])) {
704                                                 res = node->neighbour[i];
705                                                 goto out;
706                                         }
707                                         failed = 1;
708                                 }
709                         }
710                 }
711         }
712
713         if (failed) {
714                 *cause      = ROSE_OUT_OF_ORDER;
715                 *diagnostic = 0;
716         } else {
717                 *cause      = ROSE_NOT_OBTAINABLE;
718                 *diagnostic = 0;
719         }
720
721 out:
722         if (!route_frame) spin_unlock_bh(&rose_node_list_lock);
723         return res;
724 }
725
726 /*
727  *      Handle the ioctls that control the routing functions.
728  */
729 int rose_rt_ioctl(unsigned int cmd, void __user *arg)
730 {
731         struct rose_route_struct rose_route;
732         struct net_device *dev;
733         int err;
734
735         switch (cmd) {
736         case SIOCADDRT:
737                 if (copy_from_user(&rose_route, arg, sizeof(struct rose_route_struct)))
738                         return -EFAULT;
739                 if ((dev = rose_ax25_dev_find(rose_route.device)) == NULL)
740                         return -EINVAL;
741                 if (rose_dev_exists(&rose_route.address)) /* Can't add routes to ourself */
742                         return -EINVAL;
743                 if (rose_route.mask > 10) /* Mask can't be more than 10 digits */
744                         return -EINVAL;
745                 if (rose_route.ndigis > AX25_MAX_DIGIS)
746                         return -EINVAL;
747                 err = rose_add_node(&rose_route, dev);
748                 return err;
749
750         case SIOCDELRT:
751                 if (copy_from_user(&rose_route, arg, sizeof(struct rose_route_struct)))
752                         return -EFAULT;
753                 if ((dev = rose_ax25_dev_find(rose_route.device)) == NULL)
754                         return -EINVAL;
755                 err = rose_del_node(&rose_route, dev);
756                 return err;
757
758         case SIOCRSCLRRT:
759                 return rose_clear_routes();
760
761         default:
762                 return -EINVAL;
763         }
764
765         return 0;
766 }
767
768 static void rose_del_route_by_neigh(struct rose_neigh *rose_neigh)
769 {
770         struct rose_route *rose_route, *s;
771
772         rose_neigh->restarted = 0;
773
774         rose_stop_t0timer(rose_neigh);
775         rose_start_ftimer(rose_neigh);
776
777         skb_queue_purge(&rose_neigh->queue);
778
779         spin_lock_bh(&rose_route_list_lock);
780
781         rose_route = rose_route_list;
782
783         while (rose_route != NULL) {
784                 if ((rose_route->neigh1 == rose_neigh && rose_route->neigh2 == rose_neigh) ||
785                     (rose_route->neigh1 == rose_neigh && rose_route->neigh2 == NULL)       ||
786                     (rose_route->neigh2 == rose_neigh && rose_route->neigh1 == NULL)) {
787                         s = rose_route->next;
788                         rose_remove_route(rose_route);
789                         rose_route = s;
790                         continue;
791                 }
792
793                 if (rose_route->neigh1 == rose_neigh) {
794                         rose_route->neigh1->use--;
795                         rose_route->neigh1 = NULL;
796                         rose_transmit_clear_request(rose_route->neigh2, rose_route->lci2, ROSE_OUT_OF_ORDER, 0);
797                 }
798
799                 if (rose_route->neigh2 == rose_neigh) {
800                         rose_route->neigh2->use--;
801                         rose_route->neigh2 = NULL;
802                         rose_transmit_clear_request(rose_route->neigh1, rose_route->lci1, ROSE_OUT_OF_ORDER, 0);
803                 }
804
805                 rose_route = rose_route->next;
806         }
807         spin_unlock_bh(&rose_route_list_lock);
808 }
809
810 /*
811  *      A level 2 link has timed out, therefore it appears to be a poor link,
812  *      then don't use that neighbour until it is reset. Blow away all through
813  *      routes and connections using this route.
814  */
815 void rose_link_failed(ax25_cb *ax25, int reason)
816 {
817         struct rose_neigh *rose_neigh;
818
819         spin_lock_bh(&rose_neigh_list_lock);
820         rose_neigh = rose_neigh_list;
821         while (rose_neigh != NULL) {
822                 if (rose_neigh->ax25 == ax25)
823                         break;
824                 rose_neigh = rose_neigh->next;
825         }
826
827         if (rose_neigh != NULL) {
828                 rose_neigh->ax25 = NULL;
829                 ax25_cb_put(ax25);
830
831                 rose_del_route_by_neigh(rose_neigh);
832                 rose_kill_by_neigh(rose_neigh);
833         }
834         spin_unlock_bh(&rose_neigh_list_lock);
835 }
836
837 /*
838  *      A device has been "downed" remove its link status. Blow away all
839  *      through routes and connections that use this device.
840  */
841 void rose_link_device_down(struct net_device *dev)
842 {
843         struct rose_neigh *rose_neigh;
844
845         for (rose_neigh = rose_neigh_list; rose_neigh != NULL; rose_neigh = rose_neigh->next) {
846                 if (rose_neigh->dev == dev) {
847                         rose_del_route_by_neigh(rose_neigh);
848                         rose_kill_by_neigh(rose_neigh);
849                 }
850         }
851 }
852
853 /*
854  *      Route a frame to an appropriate AX.25 connection.
855  *      A NULL ax25_cb indicates an internally generated frame.
856  */
857 int rose_route_frame(struct sk_buff *skb, ax25_cb *ax25)
858 {
859         struct rose_neigh *rose_neigh, *new_neigh;
860         struct rose_route *rose_route;
861         struct rose_facilities_struct facilities;
862         rose_address *src_addr, *dest_addr;
863         struct sock *sk;
864         unsigned short frametype;
865         unsigned int lci, new_lci;
866         unsigned char cause, diagnostic;
867         struct net_device *dev;
868         int res = 0;
869         char buf[11];
870
871         if (skb->len < ROSE_MIN_LEN)
872                 return res;
873
874         if (!ax25)
875                 return rose_loopback_queue(skb, NULL);
876
877         frametype = skb->data[2];
878         lci = ((skb->data[0] << 8) & 0xF00) + ((skb->data[1] << 0) & 0x0FF);
879         if (frametype == ROSE_CALL_REQUEST &&
880             (skb->len <= ROSE_CALL_REQ_FACILITIES_OFF ||
881              skb->data[ROSE_CALL_REQ_ADDR_LEN_OFF] !=
882              ROSE_CALL_REQ_ADDR_LEN_VAL))
883                 return res;
884         src_addr  = (rose_address *)(skb->data + ROSE_CALL_REQ_SRC_ADDR_OFF);
885         dest_addr = (rose_address *)(skb->data + ROSE_CALL_REQ_DEST_ADDR_OFF);
886
887         spin_lock_bh(&rose_neigh_list_lock);
888         spin_lock_bh(&rose_route_list_lock);
889
890         rose_neigh = rose_neigh_list;
891         while (rose_neigh != NULL) {
892                 if (ax25cmp(&ax25->dest_addr, &rose_neigh->callsign) == 0 &&
893                     ax25->ax25_dev->dev == rose_neigh->dev)
894                         break;
895                 rose_neigh = rose_neigh->next;
896         }
897
898         if (rose_neigh == NULL) {
899                 printk("rose_route : unknown neighbour or device %s\n",
900                        ax2asc(buf, &ax25->dest_addr));
901                 goto out;
902         }
903
904         /*
905          *      Obviously the link is working, halt the ftimer.
906          */
907         rose_stop_ftimer(rose_neigh);
908
909         /*
910          *      LCI of zero is always for us, and its always a restart
911          *      frame.
912          */
913         if (lci == 0) {
914                 rose_link_rx_restart(skb, rose_neigh, frametype);
915                 goto out;
916         }
917
918         /*
919          *      Find an existing socket.
920          */
921         if ((sk = rose_find_socket(lci, rose_neigh)) != NULL) {
922                 if (frametype == ROSE_CALL_REQUEST) {
923                         struct rose_sock *rose = rose_sk(sk);
924
925                         /* Remove an existing unused socket */
926                         rose_clear_queues(sk);
927                         rose->cause      = ROSE_NETWORK_CONGESTION;
928                         rose->diagnostic = 0;
929                         rose->neighbour->use--;
930                         rose->neighbour  = NULL;
931                         rose->lci        = 0;
932                         rose->state      = ROSE_STATE_0;
933                         sk->sk_state     = TCP_CLOSE;
934                         sk->sk_err       = 0;
935                         sk->sk_shutdown  |= SEND_SHUTDOWN;
936                         if (!sock_flag(sk, SOCK_DEAD)) {
937                                 sk->sk_state_change(sk);
938                                 sock_set_flag(sk, SOCK_DEAD);
939                         }
940                 }
941                 else {
942                         skb_reset_transport_header(skb);
943                         res = rose_process_rx_frame(sk, skb);
944                         goto out;
945                 }
946         }
947
948         /*
949          *      Is is a Call Request and is it for us ?
950          */
951         if (frametype == ROSE_CALL_REQUEST)
952                 if ((dev = rose_dev_get(dest_addr)) != NULL) {
953                         res = rose_rx_call_request(skb, dev, rose_neigh, lci);
954                         dev_put(dev);
955                         goto out;
956                 }
957
958         if (!sysctl_rose_routing_control) {
959                 rose_transmit_clear_request(rose_neigh, lci, ROSE_NOT_OBTAINABLE, 0);
960                 goto out;
961         }
962
963         /*
964          *      Route it to the next in line if we have an entry for it.
965          */
966         rose_route = rose_route_list;
967         while (rose_route != NULL) {
968                 if (rose_route->lci1 == lci &&
969                     rose_route->neigh1 == rose_neigh) {
970                         if (frametype == ROSE_CALL_REQUEST) {
971                                 /* F6FBB - Remove an existing unused route */
972                                 rose_remove_route(rose_route);
973                                 break;
974                         } else if (rose_route->neigh2 != NULL) {
975                                 skb->data[0] &= 0xF0;
976                                 skb->data[0] |= (rose_route->lci2 >> 8) & 0x0F;
977                                 skb->data[1]  = (rose_route->lci2 >> 0) & 0xFF;
978                                 rose_transmit_link(skb, rose_route->neigh2);
979                                 if (frametype == ROSE_CLEAR_CONFIRMATION)
980                                         rose_remove_route(rose_route);
981                                 res = 1;
982                                 goto out;
983                         } else {
984                                 if (frametype == ROSE_CLEAR_CONFIRMATION)
985                                         rose_remove_route(rose_route);
986                                 goto out;
987                         }
988                 }
989                 if (rose_route->lci2 == lci &&
990                     rose_route->neigh2 == rose_neigh) {
991                         if (frametype == ROSE_CALL_REQUEST) {
992                                 /* F6FBB - Remove an existing unused route */
993                                 rose_remove_route(rose_route);
994                                 break;
995                         } else if (rose_route->neigh1 != NULL) {
996                                 skb->data[0] &= 0xF0;
997                                 skb->data[0] |= (rose_route->lci1 >> 8) & 0x0F;
998                                 skb->data[1]  = (rose_route->lci1 >> 0) & 0xFF;
999                                 rose_transmit_link(skb, rose_route->neigh1);
1000                                 if (frametype == ROSE_CLEAR_CONFIRMATION)
1001                                         rose_remove_route(rose_route);
1002                                 res = 1;
1003                                 goto out;
1004                         } else {
1005                                 if (frametype == ROSE_CLEAR_CONFIRMATION)
1006                                         rose_remove_route(rose_route);
1007                                 goto out;
1008                         }
1009                 }
1010                 rose_route = rose_route->next;
1011         }
1012
1013         /*
1014          *      We know that:
1015          *      1. The frame isn't for us,
1016          *      2. It isn't "owned" by any existing route.
1017          */
1018         if (frametype != ROSE_CALL_REQUEST) {   /* XXX */
1019                 res = 0;
1020                 goto out;
1021         }
1022
1023         memset(&facilities, 0x00, sizeof(struct rose_facilities_struct));
1024
1025         if (!rose_parse_facilities(skb->data + ROSE_CALL_REQ_FACILITIES_OFF,
1026                                    skb->len - ROSE_CALL_REQ_FACILITIES_OFF,
1027                                    &facilities)) {
1028                 rose_transmit_clear_request(rose_neigh, lci, ROSE_INVALID_FACILITY, 76);
1029                 goto out;
1030         }
1031
1032         /*
1033          *      Check for routing loops.
1034          */
1035         rose_route = rose_route_list;
1036         while (rose_route != NULL) {
1037                 if (rose_route->rand == facilities.rand &&
1038                     rosecmp(src_addr, &rose_route->src_addr) == 0 &&
1039                     ax25cmp(&facilities.dest_call, &rose_route->src_call) == 0 &&
1040                     ax25cmp(&facilities.source_call, &rose_route->dest_call) == 0) {
1041                         rose_transmit_clear_request(rose_neigh, lci, ROSE_NOT_OBTAINABLE, 120);
1042                         goto out;
1043                 }
1044                 rose_route = rose_route->next;
1045         }
1046
1047         if ((new_neigh = rose_get_neigh(dest_addr, &cause, &diagnostic, 1)) == NULL) {
1048                 rose_transmit_clear_request(rose_neigh, lci, cause, diagnostic);
1049                 goto out;
1050         }
1051
1052         if ((new_lci = rose_new_lci(new_neigh)) == 0) {
1053                 rose_transmit_clear_request(rose_neigh, lci, ROSE_NETWORK_CONGESTION, 71);
1054                 goto out;
1055         }
1056
1057         if ((rose_route = kmalloc(sizeof(*rose_route), GFP_ATOMIC)) == NULL) {
1058                 rose_transmit_clear_request(rose_neigh, lci, ROSE_NETWORK_CONGESTION, 120);
1059                 goto out;
1060         }
1061
1062         rose_route->lci1      = lci;
1063         rose_route->src_addr  = *src_addr;
1064         rose_route->dest_addr = *dest_addr;
1065         rose_route->src_call  = facilities.dest_call;
1066         rose_route->dest_call = facilities.source_call;
1067         rose_route->rand      = facilities.rand;
1068         rose_route->neigh1    = rose_neigh;
1069         rose_route->lci2      = new_lci;
1070         rose_route->neigh2    = new_neigh;
1071
1072         rose_route->neigh1->use++;
1073         rose_route->neigh2->use++;
1074
1075         rose_route->next = rose_route_list;
1076         rose_route_list  = rose_route;
1077
1078         skb->data[0] &= 0xF0;
1079         skb->data[0] |= (rose_route->lci2 >> 8) & 0x0F;
1080         skb->data[1]  = (rose_route->lci2 >> 0) & 0xFF;
1081
1082         rose_transmit_link(skb, rose_route->neigh2);
1083         res = 1;
1084
1085 out:
1086         spin_unlock_bh(&rose_route_list_lock);
1087         spin_unlock_bh(&rose_neigh_list_lock);
1088
1089         return res;
1090 }
1091
1092 #ifdef CONFIG_PROC_FS
1093
1094 static void *rose_node_start(struct seq_file *seq, loff_t *pos)
1095         __acquires(rose_node_list_lock)
1096 {
1097         struct rose_node *rose_node;
1098         int i = 1;
1099
1100         spin_lock_bh(&rose_node_list_lock);
1101         if (*pos == 0)
1102                 return SEQ_START_TOKEN;
1103
1104         for (rose_node = rose_node_list; rose_node && i < *pos;
1105              rose_node = rose_node->next, ++i);
1106
1107         return (i == *pos) ? rose_node : NULL;
1108 }
1109
1110 static void *rose_node_next(struct seq_file *seq, void *v, loff_t *pos)
1111 {
1112         ++*pos;
1113
1114         return (v == SEQ_START_TOKEN) ? rose_node_list
1115                 : ((struct rose_node *)v)->next;
1116 }
1117
1118 static void rose_node_stop(struct seq_file *seq, void *v)
1119         __releases(rose_node_list_lock)
1120 {
1121         spin_unlock_bh(&rose_node_list_lock);
1122 }
1123
1124 static int rose_node_show(struct seq_file *seq, void *v)
1125 {
1126         char rsbuf[11];
1127         int i;
1128
1129         if (v == SEQ_START_TOKEN)
1130                 seq_puts(seq, "address    mask n neigh neigh neigh\n");
1131         else {
1132                 const struct rose_node *rose_node = v;
1133                 seq_printf(seq, "%-10s %04d %d",
1134                            rose2asc(rsbuf, &rose_node->address),
1135                            rose_node->mask,
1136                            rose_node->count);
1137
1138                 for (i = 0; i < rose_node->count; i++)
1139                         seq_printf(seq, " %05d", rose_node->neighbour[i]->number);
1140
1141                 seq_puts(seq, "\n");
1142         }
1143         return 0;
1144 }
1145
1146 const struct seq_operations rose_node_seqops = {
1147         .start = rose_node_start,
1148         .next = rose_node_next,
1149         .stop = rose_node_stop,
1150         .show = rose_node_show,
1151 };
1152
1153 static void *rose_neigh_start(struct seq_file *seq, loff_t *pos)
1154         __acquires(rose_neigh_list_lock)
1155 {
1156         struct rose_neigh *rose_neigh;
1157         int i = 1;
1158
1159         spin_lock_bh(&rose_neigh_list_lock);
1160         if (*pos == 0)
1161                 return SEQ_START_TOKEN;
1162
1163         for (rose_neigh = rose_neigh_list; rose_neigh && i < *pos;
1164              rose_neigh = rose_neigh->next, ++i);
1165
1166         return (i == *pos) ? rose_neigh : NULL;
1167 }
1168
1169 static void *rose_neigh_next(struct seq_file *seq, void *v, loff_t *pos)
1170 {
1171         ++*pos;
1172
1173         return (v == SEQ_START_TOKEN) ? rose_neigh_list
1174                 : ((struct rose_neigh *)v)->next;
1175 }
1176
1177 static void rose_neigh_stop(struct seq_file *seq, void *v)
1178         __releases(rose_neigh_list_lock)
1179 {
1180         spin_unlock_bh(&rose_neigh_list_lock);
1181 }
1182
1183 static int rose_neigh_show(struct seq_file *seq, void *v)
1184 {
1185         char buf[11];
1186         int i;
1187
1188         if (v == SEQ_START_TOKEN)
1189                 seq_puts(seq,
1190                          "addr  callsign  dev  count use mode restart  t0  tf digipeaters\n");
1191         else {
1192                 struct rose_neigh *rose_neigh = v;
1193
1194                 /* if (!rose_neigh->loopback) { */
1195                 seq_printf(seq, "%05d %-9s %-4s   %3d %3d  %3s     %3s %3lu %3lu",
1196                            rose_neigh->number,
1197                            (rose_neigh->loopback) ? "RSLOOP-0" : ax2asc(buf, &rose_neigh->callsign),
1198                            rose_neigh->dev ? rose_neigh->dev->name : "???",
1199                            rose_neigh->count,
1200                            rose_neigh->use,
1201                            (rose_neigh->dce_mode) ? "DCE" : "DTE",
1202                            (rose_neigh->restarted) ? "yes" : "no",
1203                            ax25_display_timer(&rose_neigh->t0timer) / HZ,
1204                            ax25_display_timer(&rose_neigh->ftimer)  / HZ);
1205
1206                 if (rose_neigh->digipeat != NULL) {
1207                         for (i = 0; i < rose_neigh->digipeat->ndigi; i++)
1208                                 seq_printf(seq, " %s", ax2asc(buf, &rose_neigh->digipeat->calls[i]));
1209                 }
1210
1211                 seq_puts(seq, "\n");
1212         }
1213         return 0;
1214 }
1215
1216
1217 const struct seq_operations rose_neigh_seqops = {
1218         .start = rose_neigh_start,
1219         .next = rose_neigh_next,
1220         .stop = rose_neigh_stop,
1221         .show = rose_neigh_show,
1222 };
1223
1224 static void *rose_route_start(struct seq_file *seq, loff_t *pos)
1225         __acquires(rose_route_list_lock)
1226 {
1227         struct rose_route *rose_route;
1228         int i = 1;
1229
1230         spin_lock_bh(&rose_route_list_lock);
1231         if (*pos == 0)
1232                 return SEQ_START_TOKEN;
1233
1234         for (rose_route = rose_route_list; rose_route && i < *pos;
1235              rose_route = rose_route->next, ++i);
1236
1237         return (i == *pos) ? rose_route : NULL;
1238 }
1239
1240 static void *rose_route_next(struct seq_file *seq, void *v, loff_t *pos)
1241 {
1242         ++*pos;
1243
1244         return (v == SEQ_START_TOKEN) ? rose_route_list
1245                 : ((struct rose_route *)v)->next;
1246 }
1247
1248 static void rose_route_stop(struct seq_file *seq, void *v)
1249         __releases(rose_route_list_lock)
1250 {
1251         spin_unlock_bh(&rose_route_list_lock);
1252 }
1253
1254 static int rose_route_show(struct seq_file *seq, void *v)
1255 {
1256         char buf[11], rsbuf[11];
1257
1258         if (v == SEQ_START_TOKEN)
1259                 seq_puts(seq,
1260                          "lci  address     callsign   neigh  <-> lci  address     callsign   neigh\n");
1261         else {
1262                 struct rose_route *rose_route = v;
1263
1264                 if (rose_route->neigh1)
1265                         seq_printf(seq,
1266                                    "%3.3X  %-10s  %-9s  %05d      ",
1267                                    rose_route->lci1,
1268                                    rose2asc(rsbuf, &rose_route->src_addr),
1269                                    ax2asc(buf, &rose_route->src_call),
1270                                    rose_route->neigh1->number);
1271                 else
1272                         seq_puts(seq,
1273                                  "000  *           *          00000      ");
1274
1275                 if (rose_route->neigh2)
1276                         seq_printf(seq,
1277                                    "%3.3X  %-10s  %-9s  %05d\n",
1278                                    rose_route->lci2,
1279                                    rose2asc(rsbuf, &rose_route->dest_addr),
1280                                    ax2asc(buf, &rose_route->dest_call),
1281                                    rose_route->neigh2->number);
1282                  else
1283                          seq_puts(seq,
1284                                   "000  *           *          00000\n");
1285                 }
1286         return 0;
1287 }
1288
1289 struct seq_operations rose_route_seqops = {
1290         .start = rose_route_start,
1291         .next = rose_route_next,
1292         .stop = rose_route_stop,
1293         .show = rose_route_show,
1294 };
1295 #endif /* CONFIG_PROC_FS */
1296
1297 /*
1298  *      Release all memory associated with ROSE routing structures.
1299  */
1300 void __exit rose_rt_free(void)
1301 {
1302         struct rose_neigh *s, *rose_neigh = rose_neigh_list;
1303         struct rose_node  *t, *rose_node  = rose_node_list;
1304         struct rose_route *u, *rose_route = rose_route_list;
1305
1306         while (rose_neigh != NULL) {
1307                 s          = rose_neigh;
1308                 rose_neigh = rose_neigh->next;
1309
1310                 rose_remove_neigh(s);
1311         }
1312
1313         while (rose_node != NULL) {
1314                 t         = rose_node;
1315                 rose_node = rose_node->next;
1316
1317                 rose_remove_node(t);
1318         }
1319
1320         while (rose_route != NULL) {
1321                 u          = rose_route;
1322                 rose_route = rose_route->next;
1323
1324                 rose_remove_route(u);
1325         }
1326 }