MAINTAINERS: update the LSM maintainer info
[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         rose_stop_ftimer(rose_neigh);
231         rose_stop_t0timer(rose_neigh);
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         rcu_read_unlock();
619
620         return first;
621 }
622
623 /*
624  *      Find the ROSE device for the given address.
625  */
626 struct net_device *rose_dev_get(rose_address *addr)
627 {
628         struct net_device *dev;
629
630         rcu_read_lock();
631         for_each_netdev_rcu(&init_net, dev) {
632                 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_ROSE &&
633                     rosecmp(addr, (const rose_address *)dev->dev_addr) == 0) {
634                         dev_hold(dev);
635                         goto out;
636                 }
637         }
638         dev = NULL;
639 out:
640         rcu_read_unlock();
641         return dev;
642 }
643
644 static int rose_dev_exists(rose_address *addr)
645 {
646         struct net_device *dev;
647
648         rcu_read_lock();
649         for_each_netdev_rcu(&init_net, dev) {
650                 if ((dev->flags & IFF_UP) && dev->type == ARPHRD_ROSE &&
651                     rosecmp(addr, (const rose_address *)dev->dev_addr) == 0)
652                         goto out;
653         }
654         dev = NULL;
655 out:
656         rcu_read_unlock();
657         return dev != NULL;
658 }
659
660
661
662
663 struct rose_route *rose_route_free_lci(unsigned int lci, struct rose_neigh *neigh)
664 {
665         struct rose_route *rose_route;
666
667         for (rose_route = rose_route_list; rose_route != NULL; rose_route = rose_route->next)
668                 if ((rose_route->neigh1 == neigh && rose_route->lci1 == lci) ||
669                     (rose_route->neigh2 == neigh && rose_route->lci2 == lci))
670                         return rose_route;
671
672         return NULL;
673 }
674
675 /*
676  *      Find a neighbour or a route given a ROSE address.
677  */
678 struct rose_neigh *rose_get_neigh(rose_address *addr, unsigned char *cause,
679         unsigned char *diagnostic, int route_frame)
680 {
681         struct rose_neigh *res = NULL;
682         struct rose_node *node;
683         int failed = 0;
684         int i;
685
686         if (!route_frame) spin_lock_bh(&rose_node_list_lock);
687         for (node = rose_node_list; node != NULL; node = node->next) {
688                 if (rosecmpm(addr, &node->address, node->mask) == 0) {
689                         for (i = 0; i < node->count; i++) {
690                                 if (node->neighbour[i]->restarted) {
691                                         res = node->neighbour[i];
692                                         goto out;
693                                 }
694                         }
695                 }
696         }
697         if (!route_frame) { /* connect request */
698                 for (node = rose_node_list; node != NULL; node = node->next) {
699                         if (rosecmpm(addr, &node->address, node->mask) == 0) {
700                                 for (i = 0; i < node->count; i++) {
701                                         if (!rose_ftimer_running(node->neighbour[i])) {
702                                                 res = node->neighbour[i];
703                                                 goto out;
704                                         }
705                                         failed = 1;
706                                 }
707                         }
708                 }
709         }
710
711         if (failed) {
712                 *cause      = ROSE_OUT_OF_ORDER;
713                 *diagnostic = 0;
714         } else {
715                 *cause      = ROSE_NOT_OBTAINABLE;
716                 *diagnostic = 0;
717         }
718
719 out:
720         if (!route_frame) spin_unlock_bh(&rose_node_list_lock);
721         return res;
722 }
723
724 /*
725  *      Handle the ioctls that control the routing functions.
726  */
727 int rose_rt_ioctl(unsigned int cmd, void __user *arg)
728 {
729         struct rose_route_struct rose_route;
730         struct net_device *dev;
731         int err;
732
733         switch (cmd) {
734         case SIOCADDRT:
735                 if (copy_from_user(&rose_route, arg, sizeof(struct rose_route_struct)))
736                         return -EFAULT;
737                 if ((dev = rose_ax25_dev_find(rose_route.device)) == NULL)
738                         return -EINVAL;
739                 if (rose_dev_exists(&rose_route.address)) /* Can't add routes to ourself */
740                         return -EINVAL;
741                 if (rose_route.mask > 10) /* Mask can't be more than 10 digits */
742                         return -EINVAL;
743                 if (rose_route.ndigis > AX25_MAX_DIGIS)
744                         return -EINVAL;
745                 err = rose_add_node(&rose_route, dev);
746                 return err;
747
748         case SIOCDELRT:
749                 if (copy_from_user(&rose_route, arg, sizeof(struct rose_route_struct)))
750                         return -EFAULT;
751                 if ((dev = rose_ax25_dev_find(rose_route.device)) == NULL)
752                         return -EINVAL;
753                 err = rose_del_node(&rose_route, dev);
754                 return err;
755
756         case SIOCRSCLRRT:
757                 return rose_clear_routes();
758
759         default:
760                 return -EINVAL;
761         }
762
763         return 0;
764 }
765
766 static void rose_del_route_by_neigh(struct rose_neigh *rose_neigh)
767 {
768         struct rose_route *rose_route, *s;
769
770         rose_neigh->restarted = 0;
771
772         rose_stop_t0timer(rose_neigh);
773         rose_start_ftimer(rose_neigh);
774
775         skb_queue_purge(&rose_neigh->queue);
776
777         spin_lock_bh(&rose_route_list_lock);
778
779         rose_route = rose_route_list;
780
781         while (rose_route != NULL) {
782                 if ((rose_route->neigh1 == rose_neigh && rose_route->neigh2 == rose_neigh) ||
783                     (rose_route->neigh1 == rose_neigh && rose_route->neigh2 == NULL)       ||
784                     (rose_route->neigh2 == rose_neigh && rose_route->neigh1 == NULL)) {
785                         s = rose_route->next;
786                         rose_remove_route(rose_route);
787                         rose_route = s;
788                         continue;
789                 }
790
791                 if (rose_route->neigh1 == rose_neigh) {
792                         rose_route->neigh1->use--;
793                         rose_route->neigh1 = NULL;
794                         rose_transmit_clear_request(rose_route->neigh2, rose_route->lci2, ROSE_OUT_OF_ORDER, 0);
795                 }
796
797                 if (rose_route->neigh2 == rose_neigh) {
798                         rose_route->neigh2->use--;
799                         rose_route->neigh2 = NULL;
800                         rose_transmit_clear_request(rose_route->neigh1, rose_route->lci1, ROSE_OUT_OF_ORDER, 0);
801                 }
802
803                 rose_route = rose_route->next;
804         }
805         spin_unlock_bh(&rose_route_list_lock);
806 }
807
808 /*
809  *      A level 2 link has timed out, therefore it appears to be a poor link,
810  *      then don't use that neighbour until it is reset. Blow away all through
811  *      routes and connections using this route.
812  */
813 void rose_link_failed(ax25_cb *ax25, int reason)
814 {
815         struct rose_neigh *rose_neigh;
816
817         spin_lock_bh(&rose_neigh_list_lock);
818         rose_neigh = rose_neigh_list;
819         while (rose_neigh != NULL) {
820                 if (rose_neigh->ax25 == ax25)
821                         break;
822                 rose_neigh = rose_neigh->next;
823         }
824
825         if (rose_neigh != NULL) {
826                 rose_neigh->ax25 = NULL;
827                 ax25_cb_put(ax25);
828
829                 rose_del_route_by_neigh(rose_neigh);
830                 rose_kill_by_neigh(rose_neigh);
831         }
832         spin_unlock_bh(&rose_neigh_list_lock);
833 }
834
835 /*
836  *      A device has been "downed" remove its link status. Blow away all
837  *      through routes and connections that use this device.
838  */
839 void rose_link_device_down(struct net_device *dev)
840 {
841         struct rose_neigh *rose_neigh;
842
843         for (rose_neigh = rose_neigh_list; rose_neigh != NULL; rose_neigh = rose_neigh->next) {
844                 if (rose_neigh->dev == dev) {
845                         rose_del_route_by_neigh(rose_neigh);
846                         rose_kill_by_neigh(rose_neigh);
847                 }
848         }
849 }
850
851 /*
852  *      Route a frame to an appropriate AX.25 connection.
853  *      A NULL ax25_cb indicates an internally generated frame.
854  */
855 int rose_route_frame(struct sk_buff *skb, ax25_cb *ax25)
856 {
857         struct rose_neigh *rose_neigh, *new_neigh;
858         struct rose_route *rose_route;
859         struct rose_facilities_struct facilities;
860         rose_address *src_addr, *dest_addr;
861         struct sock *sk;
862         unsigned short frametype;
863         unsigned int lci, new_lci;
864         unsigned char cause, diagnostic;
865         struct net_device *dev;
866         int res = 0;
867         char buf[11];
868
869         if (skb->len < ROSE_MIN_LEN)
870                 return res;
871
872         if (!ax25)
873                 return rose_loopback_queue(skb, NULL);
874
875         frametype = skb->data[2];
876         lci = ((skb->data[0] << 8) & 0xF00) + ((skb->data[1] << 0) & 0x0FF);
877         if (frametype == ROSE_CALL_REQUEST &&
878             (skb->len <= ROSE_CALL_REQ_FACILITIES_OFF ||
879              skb->data[ROSE_CALL_REQ_ADDR_LEN_OFF] !=
880              ROSE_CALL_REQ_ADDR_LEN_VAL))
881                 return res;
882         src_addr  = (rose_address *)(skb->data + ROSE_CALL_REQ_SRC_ADDR_OFF);
883         dest_addr = (rose_address *)(skb->data + ROSE_CALL_REQ_DEST_ADDR_OFF);
884
885         spin_lock_bh(&rose_neigh_list_lock);
886         spin_lock_bh(&rose_route_list_lock);
887
888         rose_neigh = rose_neigh_list;
889         while (rose_neigh != NULL) {
890                 if (ax25cmp(&ax25->dest_addr, &rose_neigh->callsign) == 0 &&
891                     ax25->ax25_dev->dev == rose_neigh->dev)
892                         break;
893                 rose_neigh = rose_neigh->next;
894         }
895
896         if (rose_neigh == NULL) {
897                 printk("rose_route : unknown neighbour or device %s\n",
898                        ax2asc(buf, &ax25->dest_addr));
899                 goto out;
900         }
901
902         /*
903          *      Obviously the link is working, halt the ftimer.
904          */
905         rose_stop_ftimer(rose_neigh);
906
907         /*
908          *      LCI of zero is always for us, and its always a restart
909          *      frame.
910          */
911         if (lci == 0) {
912                 rose_link_rx_restart(skb, rose_neigh, frametype);
913                 goto out;
914         }
915
916         /*
917          *      Find an existing socket.
918          */
919         if ((sk = rose_find_socket(lci, rose_neigh)) != NULL) {
920                 if (frametype == ROSE_CALL_REQUEST) {
921                         struct rose_sock *rose = rose_sk(sk);
922
923                         /* Remove an existing unused socket */
924                         rose_clear_queues(sk);
925                         rose->cause      = ROSE_NETWORK_CONGESTION;
926                         rose->diagnostic = 0;
927                         rose->neighbour->use--;
928                         rose->neighbour  = NULL;
929                         rose->lci        = 0;
930                         rose->state      = ROSE_STATE_0;
931                         sk->sk_state     = TCP_CLOSE;
932                         sk->sk_err       = 0;
933                         sk->sk_shutdown  |= SEND_SHUTDOWN;
934                         if (!sock_flag(sk, SOCK_DEAD)) {
935                                 sk->sk_state_change(sk);
936                                 sock_set_flag(sk, SOCK_DEAD);
937                         }
938                 }
939                 else {
940                         skb_reset_transport_header(skb);
941                         res = rose_process_rx_frame(sk, skb);
942                         goto out;
943                 }
944         }
945
946         /*
947          *      Is is a Call Request and is it for us ?
948          */
949         if (frametype == ROSE_CALL_REQUEST)
950                 if ((dev = rose_dev_get(dest_addr)) != NULL) {
951                         res = rose_rx_call_request(skb, dev, rose_neigh, lci);
952                         dev_put(dev);
953                         goto out;
954                 }
955
956         if (!sysctl_rose_routing_control) {
957                 rose_transmit_clear_request(rose_neigh, lci, ROSE_NOT_OBTAINABLE, 0);
958                 goto out;
959         }
960
961         /*
962          *      Route it to the next in line if we have an entry for it.
963          */
964         rose_route = rose_route_list;
965         while (rose_route != NULL) {
966                 if (rose_route->lci1 == lci &&
967                     rose_route->neigh1 == rose_neigh) {
968                         if (frametype == ROSE_CALL_REQUEST) {
969                                 /* F6FBB - Remove an existing unused route */
970                                 rose_remove_route(rose_route);
971                                 break;
972                         } else if (rose_route->neigh2 != NULL) {
973                                 skb->data[0] &= 0xF0;
974                                 skb->data[0] |= (rose_route->lci2 >> 8) & 0x0F;
975                                 skb->data[1]  = (rose_route->lci2 >> 0) & 0xFF;
976                                 rose_transmit_link(skb, rose_route->neigh2);
977                                 if (frametype == ROSE_CLEAR_CONFIRMATION)
978                                         rose_remove_route(rose_route);
979                                 res = 1;
980                                 goto out;
981                         } else {
982                                 if (frametype == ROSE_CLEAR_CONFIRMATION)
983                                         rose_remove_route(rose_route);
984                                 goto out;
985                         }
986                 }
987                 if (rose_route->lci2 == lci &&
988                     rose_route->neigh2 == rose_neigh) {
989                         if (frametype == ROSE_CALL_REQUEST) {
990                                 /* F6FBB - Remove an existing unused route */
991                                 rose_remove_route(rose_route);
992                                 break;
993                         } else if (rose_route->neigh1 != NULL) {
994                                 skb->data[0] &= 0xF0;
995                                 skb->data[0] |= (rose_route->lci1 >> 8) & 0x0F;
996                                 skb->data[1]  = (rose_route->lci1 >> 0) & 0xFF;
997                                 rose_transmit_link(skb, rose_route->neigh1);
998                                 if (frametype == ROSE_CLEAR_CONFIRMATION)
999                                         rose_remove_route(rose_route);
1000                                 res = 1;
1001                                 goto out;
1002                         } else {
1003                                 if (frametype == ROSE_CLEAR_CONFIRMATION)
1004                                         rose_remove_route(rose_route);
1005                                 goto out;
1006                         }
1007                 }
1008                 rose_route = rose_route->next;
1009         }
1010
1011         /*
1012          *      We know that:
1013          *      1. The frame isn't for us,
1014          *      2. It isn't "owned" by any existing route.
1015          */
1016         if (frametype != ROSE_CALL_REQUEST) {   /* XXX */
1017                 res = 0;
1018                 goto out;
1019         }
1020
1021         memset(&facilities, 0x00, sizeof(struct rose_facilities_struct));
1022
1023         if (!rose_parse_facilities(skb->data + ROSE_CALL_REQ_FACILITIES_OFF,
1024                                    skb->len - ROSE_CALL_REQ_FACILITIES_OFF,
1025                                    &facilities)) {
1026                 rose_transmit_clear_request(rose_neigh, lci, ROSE_INVALID_FACILITY, 76);
1027                 goto out;
1028         }
1029
1030         /*
1031          *      Check for routing loops.
1032          */
1033         rose_route = rose_route_list;
1034         while (rose_route != NULL) {
1035                 if (rose_route->rand == facilities.rand &&
1036                     rosecmp(src_addr, &rose_route->src_addr) == 0 &&
1037                     ax25cmp(&facilities.dest_call, &rose_route->src_call) == 0 &&
1038                     ax25cmp(&facilities.source_call, &rose_route->dest_call) == 0) {
1039                         rose_transmit_clear_request(rose_neigh, lci, ROSE_NOT_OBTAINABLE, 120);
1040                         goto out;
1041                 }
1042                 rose_route = rose_route->next;
1043         }
1044
1045         if ((new_neigh = rose_get_neigh(dest_addr, &cause, &diagnostic, 1)) == NULL) {
1046                 rose_transmit_clear_request(rose_neigh, lci, cause, diagnostic);
1047                 goto out;
1048         }
1049
1050         if ((new_lci = rose_new_lci(new_neigh)) == 0) {
1051                 rose_transmit_clear_request(rose_neigh, lci, ROSE_NETWORK_CONGESTION, 71);
1052                 goto out;
1053         }
1054
1055         if ((rose_route = kmalloc(sizeof(*rose_route), GFP_ATOMIC)) == NULL) {
1056                 rose_transmit_clear_request(rose_neigh, lci, ROSE_NETWORK_CONGESTION, 120);
1057                 goto out;
1058         }
1059
1060         rose_route->lci1      = lci;
1061         rose_route->src_addr  = *src_addr;
1062         rose_route->dest_addr = *dest_addr;
1063         rose_route->src_call  = facilities.dest_call;
1064         rose_route->dest_call = facilities.source_call;
1065         rose_route->rand      = facilities.rand;
1066         rose_route->neigh1    = rose_neigh;
1067         rose_route->lci2      = new_lci;
1068         rose_route->neigh2    = new_neigh;
1069
1070         rose_route->neigh1->use++;
1071         rose_route->neigh2->use++;
1072
1073         rose_route->next = rose_route_list;
1074         rose_route_list  = rose_route;
1075
1076         skb->data[0] &= 0xF0;
1077         skb->data[0] |= (rose_route->lci2 >> 8) & 0x0F;
1078         skb->data[1]  = (rose_route->lci2 >> 0) & 0xFF;
1079
1080         rose_transmit_link(skb, rose_route->neigh2);
1081         res = 1;
1082
1083 out:
1084         spin_unlock_bh(&rose_route_list_lock);
1085         spin_unlock_bh(&rose_neigh_list_lock);
1086
1087         return res;
1088 }
1089
1090 #ifdef CONFIG_PROC_FS
1091
1092 static void *rose_node_start(struct seq_file *seq, loff_t *pos)
1093         __acquires(rose_node_list_lock)
1094 {
1095         struct rose_node *rose_node;
1096         int i = 1;
1097
1098         spin_lock_bh(&rose_node_list_lock);
1099         if (*pos == 0)
1100                 return SEQ_START_TOKEN;
1101
1102         for (rose_node = rose_node_list; rose_node && i < *pos;
1103              rose_node = rose_node->next, ++i);
1104
1105         return (i == *pos) ? rose_node : NULL;
1106 }
1107
1108 static void *rose_node_next(struct seq_file *seq, void *v, loff_t *pos)
1109 {
1110         ++*pos;
1111
1112         return (v == SEQ_START_TOKEN) ? rose_node_list
1113                 : ((struct rose_node *)v)->next;
1114 }
1115
1116 static void rose_node_stop(struct seq_file *seq, void *v)
1117         __releases(rose_node_list_lock)
1118 {
1119         spin_unlock_bh(&rose_node_list_lock);
1120 }
1121
1122 static int rose_node_show(struct seq_file *seq, void *v)
1123 {
1124         char rsbuf[11];
1125         int i;
1126
1127         if (v == SEQ_START_TOKEN)
1128                 seq_puts(seq, "address    mask n neigh neigh neigh\n");
1129         else {
1130                 const struct rose_node *rose_node = v;
1131                 seq_printf(seq, "%-10s %04d %d",
1132                            rose2asc(rsbuf, &rose_node->address),
1133                            rose_node->mask,
1134                            rose_node->count);
1135
1136                 for (i = 0; i < rose_node->count; i++)
1137                         seq_printf(seq, " %05d", rose_node->neighbour[i]->number);
1138
1139                 seq_puts(seq, "\n");
1140         }
1141         return 0;
1142 }
1143
1144 const struct seq_operations rose_node_seqops = {
1145         .start = rose_node_start,
1146         .next = rose_node_next,
1147         .stop = rose_node_stop,
1148         .show = rose_node_show,
1149 };
1150
1151 static void *rose_neigh_start(struct seq_file *seq, loff_t *pos)
1152         __acquires(rose_neigh_list_lock)
1153 {
1154         struct rose_neigh *rose_neigh;
1155         int i = 1;
1156
1157         spin_lock_bh(&rose_neigh_list_lock);
1158         if (*pos == 0)
1159                 return SEQ_START_TOKEN;
1160
1161         for (rose_neigh = rose_neigh_list; rose_neigh && i < *pos;
1162              rose_neigh = rose_neigh->next, ++i);
1163
1164         return (i == *pos) ? rose_neigh : NULL;
1165 }
1166
1167 static void *rose_neigh_next(struct seq_file *seq, void *v, loff_t *pos)
1168 {
1169         ++*pos;
1170
1171         return (v == SEQ_START_TOKEN) ? rose_neigh_list
1172                 : ((struct rose_neigh *)v)->next;
1173 }
1174
1175 static void rose_neigh_stop(struct seq_file *seq, void *v)
1176         __releases(rose_neigh_list_lock)
1177 {
1178         spin_unlock_bh(&rose_neigh_list_lock);
1179 }
1180
1181 static int rose_neigh_show(struct seq_file *seq, void *v)
1182 {
1183         char buf[11];
1184         int i;
1185
1186         if (v == SEQ_START_TOKEN)
1187                 seq_puts(seq,
1188                          "addr  callsign  dev  count use mode restart  t0  tf digipeaters\n");
1189         else {
1190                 struct rose_neigh *rose_neigh = v;
1191
1192                 /* if (!rose_neigh->loopback) { */
1193                 seq_printf(seq, "%05d %-9s %-4s   %3d %3d  %3s     %3s %3lu %3lu",
1194                            rose_neigh->number,
1195                            (rose_neigh->loopback) ? "RSLOOP-0" : ax2asc(buf, &rose_neigh->callsign),
1196                            rose_neigh->dev ? rose_neigh->dev->name : "???",
1197                            rose_neigh->count,
1198                            rose_neigh->use,
1199                            (rose_neigh->dce_mode) ? "DCE" : "DTE",
1200                            (rose_neigh->restarted) ? "yes" : "no",
1201                            ax25_display_timer(&rose_neigh->t0timer) / HZ,
1202                            ax25_display_timer(&rose_neigh->ftimer)  / HZ);
1203
1204                 if (rose_neigh->digipeat != NULL) {
1205                         for (i = 0; i < rose_neigh->digipeat->ndigi; i++)
1206                                 seq_printf(seq, " %s", ax2asc(buf, &rose_neigh->digipeat->calls[i]));
1207                 }
1208
1209                 seq_puts(seq, "\n");
1210         }
1211         return 0;
1212 }
1213
1214
1215 const struct seq_operations rose_neigh_seqops = {
1216         .start = rose_neigh_start,
1217         .next = rose_neigh_next,
1218         .stop = rose_neigh_stop,
1219         .show = rose_neigh_show,
1220 };
1221
1222 static void *rose_route_start(struct seq_file *seq, loff_t *pos)
1223         __acquires(rose_route_list_lock)
1224 {
1225         struct rose_route *rose_route;
1226         int i = 1;
1227
1228         spin_lock_bh(&rose_route_list_lock);
1229         if (*pos == 0)
1230                 return SEQ_START_TOKEN;
1231
1232         for (rose_route = rose_route_list; rose_route && i < *pos;
1233              rose_route = rose_route->next, ++i);
1234
1235         return (i == *pos) ? rose_route : NULL;
1236 }
1237
1238 static void *rose_route_next(struct seq_file *seq, void *v, loff_t *pos)
1239 {
1240         ++*pos;
1241
1242         return (v == SEQ_START_TOKEN) ? rose_route_list
1243                 : ((struct rose_route *)v)->next;
1244 }
1245
1246 static void rose_route_stop(struct seq_file *seq, void *v)
1247         __releases(rose_route_list_lock)
1248 {
1249         spin_unlock_bh(&rose_route_list_lock);
1250 }
1251
1252 static int rose_route_show(struct seq_file *seq, void *v)
1253 {
1254         char buf[11], rsbuf[11];
1255
1256         if (v == SEQ_START_TOKEN)
1257                 seq_puts(seq,
1258                          "lci  address     callsign   neigh  <-> lci  address     callsign   neigh\n");
1259         else {
1260                 struct rose_route *rose_route = v;
1261
1262                 if (rose_route->neigh1)
1263                         seq_printf(seq,
1264                                    "%3.3X  %-10s  %-9s  %05d      ",
1265                                    rose_route->lci1,
1266                                    rose2asc(rsbuf, &rose_route->src_addr),
1267                                    ax2asc(buf, &rose_route->src_call),
1268                                    rose_route->neigh1->number);
1269                 else
1270                         seq_puts(seq,
1271                                  "000  *           *          00000      ");
1272
1273                 if (rose_route->neigh2)
1274                         seq_printf(seq,
1275                                    "%3.3X  %-10s  %-9s  %05d\n",
1276                                    rose_route->lci2,
1277                                    rose2asc(rsbuf, &rose_route->dest_addr),
1278                                    ax2asc(buf, &rose_route->dest_call),
1279                                    rose_route->neigh2->number);
1280                  else
1281                          seq_puts(seq,
1282                                   "000  *           *          00000\n");
1283                 }
1284         return 0;
1285 }
1286
1287 struct seq_operations rose_route_seqops = {
1288         .start = rose_route_start,
1289         .next = rose_route_next,
1290         .stop = rose_route_stop,
1291         .show = rose_route_show,
1292 };
1293 #endif /* CONFIG_PROC_FS */
1294
1295 /*
1296  *      Release all memory associated with ROSE routing structures.
1297  */
1298 void __exit rose_rt_free(void)
1299 {
1300         struct rose_neigh *s, *rose_neigh = rose_neigh_list;
1301         struct rose_node  *t, *rose_node  = rose_node_list;
1302         struct rose_route *u, *rose_route = rose_route_list;
1303
1304         while (rose_neigh != NULL) {
1305                 s          = rose_neigh;
1306                 rose_neigh = rose_neigh->next;
1307
1308                 rose_remove_neigh(s);
1309         }
1310
1311         while (rose_node != NULL) {
1312                 t         = rose_node;
1313                 rose_node = rose_node->next;
1314
1315                 rose_remove_node(t);
1316         }
1317
1318         while (rose_route != NULL) {
1319                 u          = rose_route;
1320                 rose_route = rose_route->next;
1321
1322                 rose_remove_route(u);
1323         }
1324 }