xref: /linux/net/rose/rose_route.c (revision dfc349402de8e95f6a42e8341e9ea193b718eee3)
1 /*
2  * This program is free software; you can redistribute it and/or modify
3  * it under the terms of the GNU General Public License as published by
4  * the Free Software Foundation; either version 2 of the License, or
5  * (at your option) any later version.
6  *
7  * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
8  * Copyright (C) Terry Dawson VK2KTJ (terry@animats.net)
9  */
10 #include <linux/errno.h>
11 #include <linux/types.h>
12 #include <linux/socket.h>
13 #include <linux/in.h>
14 #include <linux/kernel.h>
15 #include <linux/timer.h>
16 #include <linux/string.h>
17 #include <linux/sockios.h>
18 #include <linux/net.h>
19 #include <net/ax25.h>
20 #include <linux/inet.h>
21 #include <linux/netdevice.h>
22 #include <net/arp.h>
23 #include <linux/if_arp.h>
24 #include <linux/skbuff.h>
25 #include <net/sock.h>
26 #include <net/tcp_states.h>
27 #include <asm/system.h>
28 #include <asm/uaccess.h>
29 #include <linux/fcntl.h>
30 #include <linux/termios.h>	/* For TIOCINQ/OUTQ */
31 #include <linux/mm.h>
32 #include <linux/interrupt.h>
33 #include <linux/notifier.h>
34 #include <linux/netfilter.h>
35 #include <linux/init.h>
36 #include <net/rose.h>
37 #include <linux/seq_file.h>
38 
39 static unsigned int rose_neigh_no = 1;
40 
41 static struct rose_node  *rose_node_list;
42 static DEFINE_SPINLOCK(rose_node_list_lock);
43 static struct rose_neigh *rose_neigh_list;
44 static DEFINE_SPINLOCK(rose_neigh_list_lock);
45 static struct rose_route *rose_route_list;
46 static DEFINE_SPINLOCK(rose_route_list_lock);
47 
48 struct rose_neigh *rose_loopback_neigh;
49 
50 /*
51  *	Add a new route to a node, and in the process add the node and the
52  *	neighbour if it is new.
53  */
54 static int __must_check rose_add_node(struct rose_route_struct *rose_route,
55 	struct net_device *dev)
56 {
57 	struct rose_node  *rose_node, *rose_tmpn, *rose_tmpp;
58 	struct rose_neigh *rose_neigh;
59 	int i, res = 0;
60 
61 	spin_lock_bh(&rose_node_list_lock);
62 	spin_lock_bh(&rose_neigh_list_lock);
63 
64 	rose_node = rose_node_list;
65 	while (rose_node != NULL) {
66 		if ((rose_node->mask == rose_route->mask) &&
67 		    (rosecmpm(&rose_route->address, &rose_node->address,
68 			      rose_route->mask) == 0))
69 			break;
70 		rose_node = rose_node->next;
71 	}
72 
73 	if (rose_node != NULL && rose_node->loopback) {
74 		res = -EINVAL;
75 		goto out;
76 	}
77 
78 	rose_neigh = rose_neigh_list;
79 	while (rose_neigh != NULL) {
80 		if (ax25cmp(&rose_route->neighbour, &rose_neigh->callsign) == 0
81 		    && rose_neigh->dev == dev)
82 			break;
83 		rose_neigh = rose_neigh->next;
84 	}
85 
86 	if (rose_neigh == NULL) {
87 		rose_neigh = kmalloc(sizeof(*rose_neigh), GFP_ATOMIC);
88 		if (rose_neigh == NULL) {
89 			res = -ENOMEM;
90 			goto out;
91 		}
92 
93 		rose_neigh->callsign  = rose_route->neighbour;
94 		rose_neigh->digipeat  = NULL;
95 		rose_neigh->ax25      = NULL;
96 		rose_neigh->dev       = dev;
97 		rose_neigh->count     = 0;
98 		rose_neigh->use       = 0;
99 		rose_neigh->dce_mode  = 0;
100 		rose_neigh->loopback  = 0;
101 		rose_neigh->number    = rose_neigh_no++;
102 		rose_neigh->restarted = 0;
103 
104 		skb_queue_head_init(&rose_neigh->queue);
105 
106 		init_timer(&rose_neigh->ftimer);
107 		init_timer(&rose_neigh->t0timer);
108 
109 		if (rose_route->ndigis != 0) {
110 			if ((rose_neigh->digipeat = kmalloc(sizeof(ax25_digi), GFP_KERNEL)) == 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 		kfree(rose_neigh->digipeat);
238 		kfree(rose_neigh);
239 		return;
240 	}
241 
242 	while (s != NULL && s->next != NULL) {
243 		if (s->next == rose_neigh) {
244 			s->next = rose_neigh->next;
245 			kfree(rose_neigh->digipeat);
246 			kfree(rose_neigh);
247 			return;
248 		}
249 
250 		s = s->next;
251 	}
252 }
253 
254 /*
255  * Caller is holding rose_route_list_lock.
256  */
257 static void rose_remove_route(struct rose_route *rose_route)
258 {
259 	struct rose_route *s;
260 
261 	if (rose_route->neigh1 != NULL)
262 		rose_route->neigh1->use--;
263 
264 	if (rose_route->neigh2 != NULL)
265 		rose_route->neigh2->use--;
266 
267 	if ((s = rose_route_list) == rose_route) {
268 		rose_route_list = rose_route->next;
269 		kfree(rose_route);
270 		return;
271 	}
272 
273 	while (s != NULL && s->next != NULL) {
274 		if (s->next == rose_route) {
275 			s->next = rose_route->next;
276 			kfree(rose_route);
277 			return;
278 		}
279 
280 		s = s->next;
281 	}
282 }
283 
284 /*
285  *	"Delete" a node. Strictly speaking remove a route to a node. The node
286  *	is only deleted if no routes are left to it.
287  */
288 static int rose_del_node(struct rose_route_struct *rose_route,
289 	struct net_device *dev)
290 {
291 	struct rose_node  *rose_node;
292 	struct rose_neigh *rose_neigh;
293 	int i, err = 0;
294 
295 	spin_lock_bh(&rose_node_list_lock);
296 	spin_lock_bh(&rose_neigh_list_lock);
297 
298 	rose_node = rose_node_list;
299 	while (rose_node != NULL) {
300 		if ((rose_node->mask == rose_route->mask) &&
301 		    (rosecmpm(&rose_route->address, &rose_node->address,
302 			      rose_route->mask) == 0))
303 			break;
304 		rose_node = rose_node->next;
305 	}
306 
307 	if (rose_node == NULL || rose_node->loopback) {
308 		err = -EINVAL;
309 		goto out;
310 	}
311 
312 	rose_neigh = rose_neigh_list;
313 	while (rose_neigh != NULL) {
314 		if (ax25cmp(&rose_route->neighbour, &rose_neigh->callsign) == 0
315 		    && rose_neigh->dev == dev)
316 			break;
317 		rose_neigh = rose_neigh->next;
318 	}
319 
320 	if (rose_neigh == NULL) {
321 		err = -EINVAL;
322 		goto out;
323 	}
324 
325 	for (i = 0; i < rose_node->count; i++) {
326 		if (rose_node->neighbour[i] == rose_neigh) {
327 			rose_neigh->count--;
328 
329 			if (rose_neigh->count == 0 && rose_neigh->use == 0)
330 				rose_remove_neigh(rose_neigh);
331 
332 			rose_node->count--;
333 
334 			if (rose_node->count == 0) {
335 				rose_remove_node(rose_node);
336 			} else {
337 				switch (i) {
338 				case 0:
339 					rose_node->neighbour[0] =
340 						rose_node->neighbour[1];
341 				case 1:
342 					rose_node->neighbour[1] =
343 						rose_node->neighbour[2];
344 				case 2:
345 					break;
346 				}
347 			}
348 			goto out;
349 		}
350 	}
351 	err = -EINVAL;
352 
353 out:
354 	spin_unlock_bh(&rose_neigh_list_lock);
355 	spin_unlock_bh(&rose_node_list_lock);
356 
357 	return err;
358 }
359 
360 /*
361  *	Add the loopback neighbour.
362  */
363 void rose_add_loopback_neigh(void)
364 {
365 	struct rose_neigh *sn;
366 
367 	rose_loopback_neigh = kmalloc(sizeof(struct rose_neigh), GFP_KERNEL);
368 	if (!rose_loopback_neigh)
369 		return;
370 	sn = rose_loopback_neigh;
371 
372 	sn->callsign  = null_ax25_address;
373 	sn->digipeat  = NULL;
374 	sn->ax25      = NULL;
375 	sn->dev       = NULL;
376 	sn->count     = 0;
377 	sn->use       = 0;
378 	sn->dce_mode  = 1;
379 	sn->loopback  = 1;
380 	sn->number    = rose_neigh_no++;
381 	sn->restarted = 1;
382 
383 	skb_queue_head_init(&sn->queue);
384 
385 	init_timer(&sn->ftimer);
386 	init_timer(&sn->t0timer);
387 
388 	spin_lock_bh(&rose_neigh_list_lock);
389 	sn->next = rose_neigh_list;
390 	rose_neigh_list           = sn;
391 	spin_unlock_bh(&rose_neigh_list_lock);
392 }
393 
394 /*
395  *	Add a loopback node.
396  */
397 int rose_add_loopback_node(rose_address *address)
398 {
399 	struct rose_node *rose_node;
400 	int err = 0;
401 
402 	spin_lock_bh(&rose_node_list_lock);
403 
404 	rose_node = rose_node_list;
405 	while (rose_node != NULL) {
406 		if ((rose_node->mask == 10) &&
407 		     (rosecmpm(address, &rose_node->address, 10) == 0) &&
408 		     rose_node->loopback)
409 			break;
410 		rose_node = rose_node->next;
411 	}
412 
413 	if (rose_node != NULL)
414 		goto out;
415 
416 	if ((rose_node = kmalloc(sizeof(*rose_node), GFP_ATOMIC)) == NULL) {
417 		err = -ENOMEM;
418 		goto out;
419 	}
420 
421 	rose_node->address      = *address;
422 	rose_node->mask         = 10;
423 	rose_node->count        = 1;
424 	rose_node->loopback     = 1;
425 	rose_node->neighbour[0] = rose_loopback_neigh;
426 
427 	/* Insert at the head of list. Address is always mask=10 */
428 	rose_node->next = rose_node_list;
429 	rose_node_list  = rose_node;
430 
431 	rose_loopback_neigh->count++;
432 
433 out:
434 	spin_unlock_bh(&rose_node_list_lock);
435 
436 	return err;
437 }
438 
439 /*
440  *	Delete a loopback node.
441  */
442 void rose_del_loopback_node(rose_address *address)
443 {
444 	struct rose_node *rose_node;
445 
446 	spin_lock_bh(&rose_node_list_lock);
447 
448 	rose_node = rose_node_list;
449 	while (rose_node != NULL) {
450 		if ((rose_node->mask == 10) &&
451 		    (rosecmpm(address, &rose_node->address, 10) == 0) &&
452 		    rose_node->loopback)
453 			break;
454 		rose_node = rose_node->next;
455 	}
456 
457 	if (rose_node == NULL)
458 		goto out;
459 
460 	rose_remove_node(rose_node);
461 
462 	rose_loopback_neigh->count--;
463 
464 out:
465 	spin_unlock_bh(&rose_node_list_lock);
466 }
467 
468 /*
469  *	A device has been removed. Remove its routes and neighbours.
470  */
471 void rose_rt_device_down(struct net_device *dev)
472 {
473 	struct rose_neigh *s, *rose_neigh;
474 	struct rose_node  *t, *rose_node;
475 	int i;
476 
477 	spin_lock_bh(&rose_node_list_lock);
478 	spin_lock_bh(&rose_neigh_list_lock);
479 	rose_neigh = rose_neigh_list;
480 	while (rose_neigh != NULL) {
481 		s          = rose_neigh;
482 		rose_neigh = rose_neigh->next;
483 
484 		if (s->dev != dev)
485 			continue;
486 
487 		rose_node = rose_node_list;
488 
489 		while (rose_node != NULL) {
490 			t         = rose_node;
491 			rose_node = rose_node->next;
492 
493 			for (i = 0; i < t->count; i++) {
494 				if (t->neighbour[i] != s)
495 					continue;
496 
497 				t->count--;
498 
499 				switch (i) {
500 				case 0:
501 					t->neighbour[0] = t->neighbour[1];
502 				case 1:
503 					t->neighbour[1] = t->neighbour[2];
504 				case 2:
505 					break;
506 				}
507 			}
508 
509 			if (t->count <= 0)
510 				rose_remove_node(t);
511 		}
512 
513 		rose_remove_neigh(s);
514 	}
515 	spin_unlock_bh(&rose_neigh_list_lock);
516 	spin_unlock_bh(&rose_node_list_lock);
517 }
518 
519 #if 0 /* Currently unused */
520 /*
521  *	A device has been removed. Remove its links.
522  */
523 void rose_route_device_down(struct net_device *dev)
524 {
525 	struct rose_route *s, *rose_route;
526 
527 	spin_lock_bh(&rose_route_list_lock);
528 	rose_route = rose_route_list;
529 	while (rose_route != NULL) {
530 		s          = rose_route;
531 		rose_route = rose_route->next;
532 
533 		if (s->neigh1->dev == dev || s->neigh2->dev == dev)
534 			rose_remove_route(s);
535 	}
536 	spin_unlock_bh(&rose_route_list_lock);
537 }
538 #endif
539 
540 /*
541  *	Clear all nodes and neighbours out, except for neighbours with
542  *	active connections going through them.
543  *  Do not clear loopback neighbour and nodes.
544  */
545 static int rose_clear_routes(void)
546 {
547 	struct rose_neigh *s, *rose_neigh;
548 	struct rose_node  *t, *rose_node;
549 
550 	spin_lock_bh(&rose_node_list_lock);
551 	spin_lock_bh(&rose_neigh_list_lock);
552 
553 	rose_neigh = rose_neigh_list;
554 	rose_node  = rose_node_list;
555 
556 	while (rose_node != NULL) {
557 		t         = rose_node;
558 		rose_node = rose_node->next;
559 		if (!t->loopback)
560 			rose_remove_node(t);
561 	}
562 
563 	while (rose_neigh != NULL) {
564 		s          = rose_neigh;
565 		rose_neigh = rose_neigh->next;
566 
567 		if (s->use == 0 && !s->loopback) {
568 			s->count = 0;
569 			rose_remove_neigh(s);
570 		}
571 	}
572 
573 	spin_unlock_bh(&rose_neigh_list_lock);
574 	spin_unlock_bh(&rose_node_list_lock);
575 
576 	return 0;
577 }
578 
579 /*
580  *	Check that the device given is a valid AX.25 interface that is "up".
581  * 	called whith RTNL
582  */
583 static struct net_device *rose_ax25_dev_find(char *devname)
584 {
585 	struct net_device *dev;
586 
587 	if ((dev = __dev_get_by_name(&init_net, devname)) == NULL)
588 		return NULL;
589 
590 	if ((dev->flags & IFF_UP) && dev->type == ARPHRD_AX25)
591 		return dev;
592 
593 	return NULL;
594 }
595 
596 /*
597  *	Find the first active ROSE device, usually "rose0".
598  */
599 struct net_device *rose_dev_first(void)
600 {
601 	struct net_device *dev, *first = NULL;
602 
603 	read_lock(&dev_base_lock);
604 	for_each_netdev(&init_net, dev) {
605 		if ((dev->flags & IFF_UP) && dev->type == ARPHRD_ROSE)
606 			if (first == NULL || strncmp(dev->name, first->name, 3) < 0)
607 				first = dev;
608 	}
609 	read_unlock(&dev_base_lock);
610 
611 	return first;
612 }
613 
614 /*
615  *	Find the ROSE device for the given address.
616  */
617 struct net_device *rose_dev_get(rose_address *addr)
618 {
619 	struct net_device *dev;
620 
621 	read_lock(&dev_base_lock);
622 	for_each_netdev(&init_net, dev) {
623 		if ((dev->flags & IFF_UP) && dev->type == ARPHRD_ROSE && rosecmp(addr, (rose_address *)dev->dev_addr) == 0) {
624 			dev_hold(dev);
625 			goto out;
626 		}
627 	}
628 	dev = NULL;
629 out:
630 	read_unlock(&dev_base_lock);
631 	return dev;
632 }
633 
634 static int rose_dev_exists(rose_address *addr)
635 {
636 	struct net_device *dev;
637 
638 	read_lock(&dev_base_lock);
639 	for_each_netdev(&init_net, dev) {
640 		if ((dev->flags & IFF_UP) && dev->type == ARPHRD_ROSE && rosecmp(addr, (rose_address *)dev->dev_addr) == 0)
641 			goto out;
642 	}
643 	dev = NULL;
644 out:
645 	read_unlock(&dev_base_lock);
646 	return dev != NULL;
647 }
648 
649 
650 
651 
652 struct rose_route *rose_route_free_lci(unsigned int lci, struct rose_neigh *neigh)
653 {
654 	struct rose_route *rose_route;
655 
656 	for (rose_route = rose_route_list; rose_route != NULL; rose_route = rose_route->next)
657 		if ((rose_route->neigh1 == neigh && rose_route->lci1 == lci) ||
658 		    (rose_route->neigh2 == neigh && rose_route->lci2 == lci))
659 			return rose_route;
660 
661 	return NULL;
662 }
663 
664 /*
665  *	Find a neighbour or a route given a ROSE address.
666  */
667 struct rose_neigh *rose_get_neigh(rose_address *addr, unsigned char *cause,
668 	unsigned char *diagnostic, int new)
669 {
670 	struct rose_neigh *res = NULL;
671 	struct rose_node *node;
672 	int failed = 0;
673 	int i;
674 
675 	if (!new) spin_lock_bh(&rose_node_list_lock);
676 	for (node = rose_node_list; node != NULL; node = node->next) {
677 		if (rosecmpm(addr, &node->address, node->mask) == 0) {
678 			for (i = 0; i < node->count; i++) {
679 				if (new) {
680 					if (node->neighbour[i]->restarted) {
681 						res = node->neighbour[i];
682 						goto out;
683 					}
684 				}
685 				else {
686 					if (!rose_ftimer_running(node->neighbour[i])) {
687 						res = node->neighbour[i];
688 						goto out;
689 					} else
690 						failed = 1;
691 				}
692 			}
693 		}
694 	}
695 
696 	if (failed) {
697 		*cause      = ROSE_OUT_OF_ORDER;
698 		*diagnostic = 0;
699 	} else {
700 		*cause      = ROSE_NOT_OBTAINABLE;
701 		*diagnostic = 0;
702 	}
703 
704 out:
705 	if (!new) spin_unlock_bh(&rose_node_list_lock);
706 
707 	return res;
708 }
709 
710 /*
711  *	Handle the ioctls that control the routing functions.
712  */
713 int rose_rt_ioctl(unsigned int cmd, void __user *arg)
714 {
715 	struct rose_route_struct rose_route;
716 	struct net_device *dev;
717 	int err;
718 
719 	switch (cmd) {
720 	case SIOCADDRT:
721 		if (copy_from_user(&rose_route, arg, sizeof(struct rose_route_struct)))
722 			return -EFAULT;
723 		if ((dev = rose_ax25_dev_find(rose_route.device)) == NULL)
724 			return -EINVAL;
725 		if (rose_dev_exists(&rose_route.address)) /* Can't add routes to ourself */
726 			return -EINVAL;
727 		if (rose_route.mask > 10) /* Mask can't be more than 10 digits */
728 			return -EINVAL;
729 		if (rose_route.ndigis > AX25_MAX_DIGIS)
730 			return -EINVAL;
731 		err = rose_add_node(&rose_route, dev);
732 		return err;
733 
734 	case SIOCDELRT:
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 		err = rose_del_node(&rose_route, dev);
740 		return err;
741 
742 	case SIOCRSCLRRT:
743 		return rose_clear_routes();
744 
745 	default:
746 		return -EINVAL;
747 	}
748 
749 	return 0;
750 }
751 
752 static void rose_del_route_by_neigh(struct rose_neigh *rose_neigh)
753 {
754 	struct rose_route *rose_route, *s;
755 
756 	rose_neigh->restarted = 0;
757 
758 	rose_stop_t0timer(rose_neigh);
759 	rose_start_ftimer(rose_neigh);
760 
761 	skb_queue_purge(&rose_neigh->queue);
762 
763 	spin_lock_bh(&rose_route_list_lock);
764 
765 	rose_route = rose_route_list;
766 
767 	while (rose_route != NULL) {
768 		if ((rose_route->neigh1 == rose_neigh && rose_route->neigh2 == rose_neigh) ||
769 		    (rose_route->neigh1 == rose_neigh && rose_route->neigh2 == NULL)       ||
770 		    (rose_route->neigh2 == rose_neigh && rose_route->neigh1 == NULL)) {
771 			s = rose_route->next;
772 			rose_remove_route(rose_route);
773 			rose_route = s;
774 			continue;
775 		}
776 
777 		if (rose_route->neigh1 == rose_neigh) {
778 			rose_route->neigh1->use--;
779 			rose_route->neigh1 = NULL;
780 			rose_transmit_clear_request(rose_route->neigh2, rose_route->lci2, ROSE_OUT_OF_ORDER, 0);
781 		}
782 
783 		if (rose_route->neigh2 == rose_neigh) {
784 			rose_route->neigh2->use--;
785 			rose_route->neigh2 = NULL;
786 			rose_transmit_clear_request(rose_route->neigh1, rose_route->lci1, ROSE_OUT_OF_ORDER, 0);
787 		}
788 
789 		rose_route = rose_route->next;
790 	}
791 	spin_unlock_bh(&rose_route_list_lock);
792 }
793 
794 /*
795  * 	A level 2 link has timed out, therefore it appears to be a poor link,
796  *	then don't use that neighbour until it is reset. Blow away all through
797  *	routes and connections using this route.
798  */
799 void rose_link_failed(ax25_cb *ax25, int reason)
800 {
801 	struct rose_neigh *rose_neigh;
802 
803 	spin_lock_bh(&rose_neigh_list_lock);
804 	rose_neigh = rose_neigh_list;
805 	while (rose_neigh != NULL) {
806 		if (rose_neigh->ax25 == ax25)
807 			break;
808 		rose_neigh = rose_neigh->next;
809 	}
810 
811 	if (rose_neigh != NULL) {
812 		rose_neigh->ax25 = NULL;
813 
814 		rose_del_route_by_neigh(rose_neigh);
815 		rose_kill_by_neigh(rose_neigh);
816 	}
817 	spin_unlock_bh(&rose_neigh_list_lock);
818 }
819 
820 /*
821  * 	A device has been "downed" remove its link status. Blow away all
822  *	through routes and connections that use this device.
823  */
824 void rose_link_device_down(struct net_device *dev)
825 {
826 	struct rose_neigh *rose_neigh;
827 
828 	for (rose_neigh = rose_neigh_list; rose_neigh != NULL; rose_neigh = rose_neigh->next) {
829 		if (rose_neigh->dev == dev) {
830 			rose_del_route_by_neigh(rose_neigh);
831 			rose_kill_by_neigh(rose_neigh);
832 		}
833 	}
834 }
835 
836 /*
837  *	Route a frame to an appropriate AX.25 connection.
838  */
839 int rose_route_frame(struct sk_buff *skb, ax25_cb *ax25)
840 {
841 	struct rose_neigh *rose_neigh, *new_neigh;
842 	struct rose_route *rose_route;
843 	struct rose_facilities_struct facilities;
844 	rose_address *src_addr, *dest_addr;
845 	struct sock *sk;
846 	unsigned short frametype;
847 	unsigned int lci, new_lci;
848 	unsigned char cause, diagnostic;
849 	struct net_device *dev;
850 	int len, res = 0;
851 	char buf[11];
852 
853 #if 0
854 	if (call_in_firewall(PF_ROSE, skb->dev, skb->data, NULL, &skb) != FW_ACCEPT)
855 		return res;
856 #endif
857 
858 	frametype = skb->data[2];
859 	lci = ((skb->data[0] << 8) & 0xF00) + ((skb->data[1] << 0) & 0x0FF);
860 	src_addr  = (rose_address *)(skb->data + 9);
861 	dest_addr = (rose_address *)(skb->data + 4);
862 
863 	spin_lock_bh(&rose_neigh_list_lock);
864 	spin_lock_bh(&rose_route_list_lock);
865 
866 	rose_neigh = rose_neigh_list;
867 	while (rose_neigh != NULL) {
868 		if (ax25cmp(&ax25->dest_addr, &rose_neigh->callsign) == 0 &&
869 		    ax25->ax25_dev->dev == rose_neigh->dev)
870 			break;
871 		rose_neigh = rose_neigh->next;
872 	}
873 
874 	if (rose_neigh == NULL) {
875 		printk("rose_route : unknown neighbour or device %s\n",
876 		       ax2asc(buf, &ax25->dest_addr));
877 		goto out;
878 	}
879 
880 	/*
881 	 *	Obviously the link is working, halt the ftimer.
882 	 */
883 	rose_stop_ftimer(rose_neigh);
884 
885 	/*
886 	 *	LCI of zero is always for us, and its always a restart
887 	 * 	frame.
888 	 */
889 	if (lci == 0) {
890 		rose_link_rx_restart(skb, rose_neigh, frametype);
891 		goto out;
892 	}
893 
894 	/*
895 	 *	Find an existing socket.
896 	 */
897 	if ((sk = rose_find_socket(lci, rose_neigh)) != NULL) {
898 		if (frametype == ROSE_CALL_REQUEST) {
899 			struct rose_sock *rose = rose_sk(sk);
900 
901 			/* Remove an existing unused socket */
902 			rose_clear_queues(sk);
903 			rose->cause	 = ROSE_NETWORK_CONGESTION;
904 			rose->diagnostic = 0;
905 			rose->neighbour->use--;
906 			rose->neighbour	 = NULL;
907 			rose->lci	 = 0;
908 			rose->state	 = ROSE_STATE_0;
909 			sk->sk_state	 = TCP_CLOSE;
910 			sk->sk_err	 = 0;
911 			sk->sk_shutdown	 |= SEND_SHUTDOWN;
912 			if (!sock_flag(sk, SOCK_DEAD)) {
913 				sk->sk_state_change(sk);
914 				sock_set_flag(sk, SOCK_DEAD);
915 			}
916 		}
917 		else {
918 			skb_reset_transport_header(skb);
919 			res = rose_process_rx_frame(sk, skb);
920 			goto out;
921 		}
922 	}
923 
924 	/*
925 	 *	Is is a Call Request and is it for us ?
926 	 */
927 	if (frametype == ROSE_CALL_REQUEST)
928 		if ((dev = rose_dev_get(dest_addr)) != NULL) {
929 			res = rose_rx_call_request(skb, dev, rose_neigh, lci);
930 			dev_put(dev);
931 			goto out;
932 		}
933 
934 	if (!sysctl_rose_routing_control) {
935 		rose_transmit_clear_request(rose_neigh, lci, ROSE_NOT_OBTAINABLE, 0);
936 		goto out;
937 	}
938 
939 	/*
940 	 *	Route it to the next in line if we have an entry for it.
941 	 */
942 	rose_route = rose_route_list;
943 	while (rose_route != NULL) {
944 		if (rose_route->lci1 == lci &&
945 		    rose_route->neigh1 == rose_neigh) {
946 			if (frametype == ROSE_CALL_REQUEST) {
947 				/* F6FBB - Remove an existing unused route */
948 				rose_remove_route(rose_route);
949 				break;
950 			} else if (rose_route->neigh2 != NULL) {
951 				skb->data[0] &= 0xF0;
952 				skb->data[0] |= (rose_route->lci2 >> 8) & 0x0F;
953 				skb->data[1]  = (rose_route->lci2 >> 0) & 0xFF;
954 				rose_transmit_link(skb, rose_route->neigh2);
955 				if (frametype == ROSE_CLEAR_CONFIRMATION)
956 					rose_remove_route(rose_route);
957 				res = 1;
958 				goto out;
959 			} else {
960 				if (frametype == ROSE_CLEAR_CONFIRMATION)
961 					rose_remove_route(rose_route);
962 				goto out;
963 			}
964 		}
965 		if (rose_route->lci2 == lci &&
966 		    rose_route->neigh2 == rose_neigh) {
967 			if (frametype == ROSE_CALL_REQUEST) {
968 				/* F6FBB - Remove an existing unused route */
969 				rose_remove_route(rose_route);
970 				break;
971 			} else if (rose_route->neigh1 != NULL) {
972 				skb->data[0] &= 0xF0;
973 				skb->data[0] |= (rose_route->lci1 >> 8) & 0x0F;
974 				skb->data[1]  = (rose_route->lci1 >> 0) & 0xFF;
975 				rose_transmit_link(skb, rose_route->neigh1);
976 				if (frametype == ROSE_CLEAR_CONFIRMATION)
977 					rose_remove_route(rose_route);
978 				res = 1;
979 				goto out;
980 			} else {
981 				if (frametype == ROSE_CLEAR_CONFIRMATION)
982 					rose_remove_route(rose_route);
983 				goto out;
984 			}
985 		}
986 		rose_route = rose_route->next;
987 	}
988 
989 	/*
990 	 *	We know that:
991 	 *	1. The frame isn't for us,
992 	 *	2. It isn't "owned" by any existing route.
993 	 */
994 	if (frametype != ROSE_CALL_REQUEST) {	/* XXX */
995 		res = 0;
996 		goto out;
997 	}
998 
999 	len  = (((skb->data[3] >> 4) & 0x0F) + 1) >> 1;
1000 	len += (((skb->data[3] >> 0) & 0x0F) + 1) >> 1;
1001 
1002 	memset(&facilities, 0x00, sizeof(struct rose_facilities_struct));
1003 
1004 	if (!rose_parse_facilities(skb->data + len + 4, &facilities)) {
1005 		rose_transmit_clear_request(rose_neigh, lci, ROSE_INVALID_FACILITY, 76);
1006 		goto out;
1007 	}
1008 
1009 	/*
1010 	 *	Check for routing loops.
1011 	 */
1012 	rose_route = rose_route_list;
1013 	while (rose_route != NULL) {
1014 		if (rose_route->rand == facilities.rand &&
1015 		    rosecmp(src_addr, &rose_route->src_addr) == 0 &&
1016 		    ax25cmp(&facilities.dest_call, &rose_route->src_call) == 0 &&
1017 		    ax25cmp(&facilities.source_call, &rose_route->dest_call) == 0) {
1018 			rose_transmit_clear_request(rose_neigh, lci, ROSE_NOT_OBTAINABLE, 120);
1019 			goto out;
1020 		}
1021 		rose_route = rose_route->next;
1022 	}
1023 
1024 	if ((new_neigh = rose_get_neigh(dest_addr, &cause, &diagnostic, 1)) == NULL) {
1025 		rose_transmit_clear_request(rose_neigh, lci, cause, diagnostic);
1026 		goto out;
1027 	}
1028 
1029 	if ((new_lci = rose_new_lci(new_neigh)) == 0) {
1030 		rose_transmit_clear_request(rose_neigh, lci, ROSE_NETWORK_CONGESTION, 71);
1031 		goto out;
1032 	}
1033 
1034 	if ((rose_route = kmalloc(sizeof(*rose_route), GFP_ATOMIC)) == NULL) {
1035 		rose_transmit_clear_request(rose_neigh, lci, ROSE_NETWORK_CONGESTION, 120);
1036 		goto out;
1037 	}
1038 
1039 	rose_route->lci1      = lci;
1040 	rose_route->src_addr  = *src_addr;
1041 	rose_route->dest_addr = *dest_addr;
1042 	rose_route->src_call  = facilities.dest_call;
1043 	rose_route->dest_call = facilities.source_call;
1044 	rose_route->rand      = facilities.rand;
1045 	rose_route->neigh1    = rose_neigh;
1046 	rose_route->lci2      = new_lci;
1047 	rose_route->neigh2    = new_neigh;
1048 
1049 	rose_route->neigh1->use++;
1050 	rose_route->neigh2->use++;
1051 
1052 	rose_route->next = rose_route_list;
1053 	rose_route_list  = rose_route;
1054 
1055 	skb->data[0] &= 0xF0;
1056 	skb->data[0] |= (rose_route->lci2 >> 8) & 0x0F;
1057 	skb->data[1]  = (rose_route->lci2 >> 0) & 0xFF;
1058 
1059 	rose_transmit_link(skb, rose_route->neigh2);
1060 	res = 1;
1061 
1062 out:
1063 	spin_unlock_bh(&rose_route_list_lock);
1064 	spin_unlock_bh(&rose_neigh_list_lock);
1065 
1066 	return res;
1067 }
1068 
1069 #ifdef CONFIG_PROC_FS
1070 
1071 static void *rose_node_start(struct seq_file *seq, loff_t *pos)
1072 	__acquires(rose_node_list_lock)
1073 {
1074 	struct rose_node *rose_node;
1075 	int i = 1;
1076 
1077 	spin_lock_bh(&rose_node_list_lock);
1078 	if (*pos == 0)
1079 		return SEQ_START_TOKEN;
1080 
1081 	for (rose_node = rose_node_list; rose_node && i < *pos;
1082 	     rose_node = rose_node->next, ++i);
1083 
1084 	return (i == *pos) ? rose_node : NULL;
1085 }
1086 
1087 static void *rose_node_next(struct seq_file *seq, void *v, loff_t *pos)
1088 {
1089 	++*pos;
1090 
1091 	return (v == SEQ_START_TOKEN) ? rose_node_list
1092 		: ((struct rose_node *)v)->next;
1093 }
1094 
1095 static void rose_node_stop(struct seq_file *seq, void *v)
1096 	__releases(rose_node_list_lock)
1097 {
1098 	spin_unlock_bh(&rose_node_list_lock);
1099 }
1100 
1101 static int rose_node_show(struct seq_file *seq, void *v)
1102 {
1103 	char rsbuf[11];
1104 	int i;
1105 
1106 	if (v == SEQ_START_TOKEN)
1107 		seq_puts(seq, "address    mask n neigh neigh neigh\n");
1108 	else {
1109 		const struct rose_node *rose_node = v;
1110 		/* if (rose_node->loopback) {
1111 			seq_printf(seq, "%-10s %04d 1 loopback\n",
1112 				   rose2asc(rsbuf, &rose_node->address),
1113 				   rose_node->mask);
1114 		} else { */
1115 			seq_printf(seq, "%-10s %04d %d",
1116 				   rose2asc(rsbuf, &rose_node->address),
1117 				   rose_node->mask,
1118 				   rose_node->count);
1119 
1120 			for (i = 0; i < rose_node->count; i++)
1121 				seq_printf(seq, " %05d",
1122 					rose_node->neighbour[i]->number);
1123 
1124 			seq_puts(seq, "\n");
1125 		/* } */
1126 	}
1127 	return 0;
1128 }
1129 
1130 static const struct seq_operations rose_node_seqops = {
1131 	.start = rose_node_start,
1132 	.next = rose_node_next,
1133 	.stop = rose_node_stop,
1134 	.show = rose_node_show,
1135 };
1136 
1137 static int rose_nodes_open(struct inode *inode, struct file *file)
1138 {
1139 	return seq_open(file, &rose_node_seqops);
1140 }
1141 
1142 const struct file_operations rose_nodes_fops = {
1143 	.owner = THIS_MODULE,
1144 	.open = rose_nodes_open,
1145 	.read = seq_read,
1146 	.llseek = seq_lseek,
1147 	.release = seq_release,
1148 };
1149 
1150 static void *rose_neigh_start(struct seq_file *seq, loff_t *pos)
1151 	__acquires(rose_neigh_list_lock)
1152 {
1153 	struct rose_neigh *rose_neigh;
1154 	int i = 1;
1155 
1156 	spin_lock_bh(&rose_neigh_list_lock);
1157 	if (*pos == 0)
1158 		return SEQ_START_TOKEN;
1159 
1160 	for (rose_neigh = rose_neigh_list; rose_neigh && i < *pos;
1161 	     rose_neigh = rose_neigh->next, ++i);
1162 
1163 	return (i == *pos) ? rose_neigh : NULL;
1164 }
1165 
1166 static void *rose_neigh_next(struct seq_file *seq, void *v, loff_t *pos)
1167 {
1168 	++*pos;
1169 
1170 	return (v == SEQ_START_TOKEN) ? rose_neigh_list
1171 		: ((struct rose_neigh *)v)->next;
1172 }
1173 
1174 static void rose_neigh_stop(struct seq_file *seq, void *v)
1175 	__releases(rose_neigh_list_lock)
1176 {
1177 	spin_unlock_bh(&rose_neigh_list_lock);
1178 }
1179 
1180 static int rose_neigh_show(struct seq_file *seq, void *v)
1181 {
1182 	char buf[11];
1183 	int i;
1184 
1185 	if (v == SEQ_START_TOKEN)
1186 		seq_puts(seq,
1187 			 "addr  callsign  dev  count use mode restart  t0  tf digipeaters\n");
1188 	else {
1189 		struct rose_neigh *rose_neigh = v;
1190 
1191 		/* if (!rose_neigh->loopback) { */
1192 		seq_printf(seq, "%05d %-9s %-4s   %3d %3d  %3s     %3s %3lu %3lu",
1193 			   rose_neigh->number,
1194 			   (rose_neigh->loopback) ? "RSLOOP-0" : ax2asc(buf, &rose_neigh->callsign),
1195 			   rose_neigh->dev ? rose_neigh->dev->name : "???",
1196 			   rose_neigh->count,
1197 			   rose_neigh->use,
1198 			   (rose_neigh->dce_mode) ? "DCE" : "DTE",
1199 			   (rose_neigh->restarted) ? "yes" : "no",
1200 			   ax25_display_timer(&rose_neigh->t0timer) / HZ,
1201 			   ax25_display_timer(&rose_neigh->ftimer)  / HZ);
1202 
1203 		if (rose_neigh->digipeat != NULL) {
1204 			for (i = 0; i < rose_neigh->digipeat->ndigi; i++)
1205 				seq_printf(seq, " %s", ax2asc(buf, &rose_neigh->digipeat->calls[i]));
1206 		}
1207 
1208 		seq_puts(seq, "\n");
1209 	}
1210 	return 0;
1211 }
1212 
1213 
1214 static const struct seq_operations rose_neigh_seqops = {
1215 	.start = rose_neigh_start,
1216 	.next = rose_neigh_next,
1217 	.stop = rose_neigh_stop,
1218 	.show = rose_neigh_show,
1219 };
1220 
1221 static int rose_neigh_open(struct inode *inode, struct file *file)
1222 {
1223 	return seq_open(file, &rose_neigh_seqops);
1224 }
1225 
1226 const struct file_operations rose_neigh_fops = {
1227 	.owner = THIS_MODULE,
1228 	.open = rose_neigh_open,
1229 	.read = seq_read,
1230 	.llseek = seq_lseek,
1231 	.release = seq_release,
1232 };
1233 
1234 
1235 static void *rose_route_start(struct seq_file *seq, loff_t *pos)
1236 	__acquires(rose_route_list_lock)
1237 {
1238 	struct rose_route *rose_route;
1239 	int i = 1;
1240 
1241 	spin_lock_bh(&rose_route_list_lock);
1242 	if (*pos == 0)
1243 		return SEQ_START_TOKEN;
1244 
1245 	for (rose_route = rose_route_list; rose_route && i < *pos;
1246 	     rose_route = rose_route->next, ++i);
1247 
1248 	return (i == *pos) ? rose_route : NULL;
1249 }
1250 
1251 static void *rose_route_next(struct seq_file *seq, void *v, loff_t *pos)
1252 {
1253 	++*pos;
1254 
1255 	return (v == SEQ_START_TOKEN) ? rose_route_list
1256 		: ((struct rose_route *)v)->next;
1257 }
1258 
1259 static void rose_route_stop(struct seq_file *seq, void *v)
1260 	__releases(rose_route_list_lock)
1261 {
1262 	spin_unlock_bh(&rose_route_list_lock);
1263 }
1264 
1265 static int rose_route_show(struct seq_file *seq, void *v)
1266 {
1267 	char buf[11], rsbuf[11];
1268 
1269 	if (v == SEQ_START_TOKEN)
1270 		seq_puts(seq,
1271 			 "lci  address     callsign   neigh  <-> lci  address     callsign   neigh\n");
1272 	else {
1273 		struct rose_route *rose_route = v;
1274 
1275 		if (rose_route->neigh1)
1276 			seq_printf(seq,
1277 				   "%3.3X  %-10s  %-9s  %05d      ",
1278 				   rose_route->lci1,
1279 				   rose2asc(rsbuf, &rose_route->src_addr),
1280 				   ax2asc(buf, &rose_route->src_call),
1281 				   rose_route->neigh1->number);
1282 		else
1283 			seq_puts(seq,
1284 				 "000  *           *          00000      ");
1285 
1286 		if (rose_route->neigh2)
1287 			seq_printf(seq,
1288 				   "%3.3X  %-10s  %-9s  %05d\n",
1289 				   rose_route->lci2,
1290 				   rose2asc(rsbuf, &rose_route->dest_addr),
1291 				   ax2asc(buf, &rose_route->dest_call),
1292 				   rose_route->neigh2->number);
1293 		 else
1294 			 seq_puts(seq,
1295 				  "000  *           *          00000\n");
1296 		}
1297 	return 0;
1298 }
1299 
1300 static const struct seq_operations rose_route_seqops = {
1301 	.start = rose_route_start,
1302 	.next = rose_route_next,
1303 	.stop = rose_route_stop,
1304 	.show = rose_route_show,
1305 };
1306 
1307 static int rose_route_open(struct inode *inode, struct file *file)
1308 {
1309 	return seq_open(file, &rose_route_seqops);
1310 }
1311 
1312 const struct file_operations rose_routes_fops = {
1313 	.owner = THIS_MODULE,
1314 	.open = rose_route_open,
1315 	.read = seq_read,
1316 	.llseek = seq_lseek,
1317 	.release = seq_release,
1318 };
1319 
1320 #endif /* CONFIG_PROC_FS */
1321 
1322 /*
1323  *	Release all memory associated with ROSE routing structures.
1324  */
1325 void __exit rose_rt_free(void)
1326 {
1327 	struct rose_neigh *s, *rose_neigh = rose_neigh_list;
1328 	struct rose_node  *t, *rose_node  = rose_node_list;
1329 	struct rose_route *u, *rose_route = rose_route_list;
1330 
1331 	while (rose_neigh != NULL) {
1332 		s          = rose_neigh;
1333 		rose_neigh = rose_neigh->next;
1334 
1335 		rose_remove_neigh(s);
1336 	}
1337 
1338 	while (rose_node != NULL) {
1339 		t         = rose_node;
1340 		rose_node = rose_node->next;
1341 
1342 		rose_remove_node(t);
1343 	}
1344 
1345 	while (rose_route != NULL) {
1346 		u          = rose_route;
1347 		rose_route = rose_route->next;
1348 
1349 		rose_remove_route(u);
1350 	}
1351 }
1352