xref: /linux/net/rose/rose_route.c (revision c537b994505099b7197e7d3125b942ecbcc51eb6)
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 = &rose_loopback_neigh;
366 
367 	sn->callsign  = null_ax25_address;
368 	sn->digipeat  = NULL;
369 	sn->ax25      = NULL;
370 	sn->dev       = NULL;
371 	sn->count     = 0;
372 	sn->use       = 0;
373 	sn->dce_mode  = 1;
374 	sn->loopback  = 1;
375 	sn->number    = rose_neigh_no++;
376 	sn->restarted = 1;
377 
378 	skb_queue_head_init(&sn->queue);
379 
380 	init_timer(&sn->ftimer);
381 	init_timer(&sn->t0timer);
382 
383 	spin_lock_bh(&rose_neigh_list_lock);
384 	sn->next = rose_neigh_list;
385 	rose_neigh_list           = sn;
386 	spin_unlock_bh(&rose_neigh_list_lock);
387 }
388 
389 /*
390  *	Add a loopback node.
391  */
392 int rose_add_loopback_node(rose_address *address)
393 {
394 	struct rose_node *rose_node;
395 	int err = 0;
396 
397 	spin_lock_bh(&rose_node_list_lock);
398 
399 	rose_node = rose_node_list;
400 	while (rose_node != NULL) {
401 		if ((rose_node->mask == 10) &&
402 		     (rosecmpm(address, &rose_node->address, 10) == 0) &&
403 		     rose_node->loopback)
404 			break;
405 		rose_node = rose_node->next;
406 	}
407 
408 	if (rose_node != NULL)
409 		goto out;
410 
411 	if ((rose_node = kmalloc(sizeof(*rose_node), GFP_ATOMIC)) == NULL) {
412 		err = -ENOMEM;
413 		goto out;
414 	}
415 
416 	rose_node->address      = *address;
417 	rose_node->mask         = 10;
418 	rose_node->count        = 1;
419 	rose_node->loopback     = 1;
420 	rose_node->neighbour[0] = &rose_loopback_neigh;
421 
422 	/* Insert at the head of list. Address is always mask=10 */
423 	rose_node->next = rose_node_list;
424 	rose_node_list  = rose_node;
425 
426 	rose_loopback_neigh.count++;
427 
428 out:
429 	spin_unlock_bh(&rose_node_list_lock);
430 
431 	return err;
432 }
433 
434 /*
435  *	Delete a loopback node.
436  */
437 void rose_del_loopback_node(rose_address *address)
438 {
439 	struct rose_node *rose_node;
440 
441 	spin_lock_bh(&rose_node_list_lock);
442 
443 	rose_node = rose_node_list;
444 	while (rose_node != NULL) {
445 		if ((rose_node->mask == 10) &&
446 		    (rosecmpm(address, &rose_node->address, 10) == 0) &&
447 		    rose_node->loopback)
448 			break;
449 		rose_node = rose_node->next;
450 	}
451 
452 	if (rose_node == NULL)
453 		goto out;
454 
455 	rose_remove_node(rose_node);
456 
457 	rose_loopback_neigh.count--;
458 
459 out:
460 	spin_unlock_bh(&rose_node_list_lock);
461 }
462 
463 /*
464  *	A device has been removed. Remove its routes and neighbours.
465  */
466 void rose_rt_device_down(struct net_device *dev)
467 {
468 	struct rose_neigh *s, *rose_neigh;
469 	struct rose_node  *t, *rose_node;
470 	int i;
471 
472 	spin_lock_bh(&rose_node_list_lock);
473 	spin_lock_bh(&rose_neigh_list_lock);
474 	rose_neigh = rose_neigh_list;
475 	while (rose_neigh != NULL) {
476 		s          = rose_neigh;
477 		rose_neigh = rose_neigh->next;
478 
479 		if (s->dev != dev)
480 			continue;
481 
482 		rose_node = rose_node_list;
483 
484 		while (rose_node != NULL) {
485 			t         = rose_node;
486 			rose_node = rose_node->next;
487 
488 			for (i = 0; i < t->count; i++) {
489 				if (t->neighbour[i] != s)
490 					continue;
491 
492 				t->count--;
493 
494 				switch (i) {
495 				case 0:
496 					t->neighbour[0] = t->neighbour[1];
497 				case 1:
498 					t->neighbour[1] = t->neighbour[2];
499 				case 2:
500 					break;
501 				}
502 			}
503 
504 			if (t->count <= 0)
505 				rose_remove_node(t);
506 		}
507 
508 		rose_remove_neigh(s);
509 	}
510 	spin_unlock_bh(&rose_neigh_list_lock);
511 	spin_unlock_bh(&rose_node_list_lock);
512 }
513 
514 #if 0 /* Currently unused */
515 /*
516  *	A device has been removed. Remove its links.
517  */
518 void rose_route_device_down(struct net_device *dev)
519 {
520 	struct rose_route *s, *rose_route;
521 
522 	spin_lock_bh(&rose_route_list_lock);
523 	rose_route = rose_route_list;
524 	while (rose_route != NULL) {
525 		s          = rose_route;
526 		rose_route = rose_route->next;
527 
528 		if (s->neigh1->dev == dev || s->neigh2->dev == dev)
529 			rose_remove_route(s);
530 	}
531 	spin_unlock_bh(&rose_route_list_lock);
532 }
533 #endif
534 
535 /*
536  *	Clear all nodes and neighbours out, except for neighbours with
537  *	active connections going through them.
538  *  Do not clear loopback neighbour and nodes.
539  */
540 static int rose_clear_routes(void)
541 {
542 	struct rose_neigh *s, *rose_neigh;
543 	struct rose_node  *t, *rose_node;
544 
545 	spin_lock_bh(&rose_node_list_lock);
546 	spin_lock_bh(&rose_neigh_list_lock);
547 
548 	rose_neigh = rose_neigh_list;
549 	rose_node  = rose_node_list;
550 
551 	while (rose_node != NULL) {
552 		t         = rose_node;
553 		rose_node = rose_node->next;
554 		if (!t->loopback)
555 			rose_remove_node(t);
556 	}
557 
558 	while (rose_neigh != NULL) {
559 		s          = rose_neigh;
560 		rose_neigh = rose_neigh->next;
561 
562 		if (s->use == 0 && !s->loopback) {
563 			s->count = 0;
564 			rose_remove_neigh(s);
565 		}
566 	}
567 
568 	spin_unlock_bh(&rose_neigh_list_lock);
569 	spin_unlock_bh(&rose_node_list_lock);
570 
571 	return 0;
572 }
573 
574 /*
575  *	Check that the device given is a valid AX.25 interface that is "up".
576  */
577 static struct net_device *rose_ax25_dev_get(char *devname)
578 {
579 	struct net_device *dev;
580 
581 	if ((dev = dev_get_by_name(devname)) == NULL)
582 		return NULL;
583 
584 	if ((dev->flags & IFF_UP) && dev->type == ARPHRD_AX25)
585 		return dev;
586 
587 	dev_put(dev);
588 	return NULL;
589 }
590 
591 /*
592  *	Find the first active ROSE device, usually "rose0".
593  */
594 struct net_device *rose_dev_first(void)
595 {
596 	struct net_device *dev, *first = NULL;
597 
598 	read_lock(&dev_base_lock);
599 	for (dev = dev_base; dev != NULL; dev = dev->next) {
600 		if ((dev->flags & IFF_UP) && dev->type == ARPHRD_ROSE)
601 			if (first == NULL || strncmp(dev->name, first->name, 3) < 0)
602 				first = dev;
603 	}
604 	read_unlock(&dev_base_lock);
605 
606 	return first;
607 }
608 
609 /*
610  *	Find the ROSE device for the given address.
611  */
612 struct net_device *rose_dev_get(rose_address *addr)
613 {
614 	struct net_device *dev;
615 
616 	read_lock(&dev_base_lock);
617 	for (dev = dev_base; dev != NULL; dev = dev->next) {
618 		if ((dev->flags & IFF_UP) && dev->type == ARPHRD_ROSE && rosecmp(addr, (rose_address *)dev->dev_addr) == 0) {
619 			dev_hold(dev);
620 			goto out;
621 		}
622 	}
623 out:
624 	read_unlock(&dev_base_lock);
625 	return dev;
626 }
627 
628 static int rose_dev_exists(rose_address *addr)
629 {
630 	struct net_device *dev;
631 
632 	read_lock(&dev_base_lock);
633 	for (dev = dev_base; dev != NULL; dev = dev->next) {
634 		if ((dev->flags & IFF_UP) && dev->type == ARPHRD_ROSE && rosecmp(addr, (rose_address *)dev->dev_addr) == 0)
635 			goto out;
636 	}
637 out:
638 	read_unlock(&dev_base_lock);
639 	return dev != NULL;
640 }
641 
642 
643 
644 
645 struct rose_route *rose_route_free_lci(unsigned int lci, struct rose_neigh *neigh)
646 {
647 	struct rose_route *rose_route;
648 
649 	for (rose_route = rose_route_list; rose_route != NULL; rose_route = rose_route->next)
650 		if ((rose_route->neigh1 == neigh && rose_route->lci1 == lci) ||
651 		    (rose_route->neigh2 == neigh && rose_route->lci2 == lci))
652 			return rose_route;
653 
654 	return NULL;
655 }
656 
657 /*
658  *	Find a neighbour given a ROSE address.
659  */
660 struct rose_neigh *rose_get_neigh(rose_address *addr, unsigned char *cause,
661 	unsigned char *diagnostic)
662 {
663 	struct rose_neigh *res = NULL;
664 	struct rose_node *node;
665 	int failed = 0;
666 	int i;
667 
668 	spin_lock_bh(&rose_node_list_lock);
669 	for (node = rose_node_list; node != NULL; node = node->next) {
670 		if (rosecmpm(addr, &node->address, node->mask) == 0) {
671 			for (i = 0; i < node->count; i++) {
672 				if (!rose_ftimer_running(node->neighbour[i])) {
673 					res = node->neighbour[i];
674 					goto out;
675 				} else
676 					failed = 1;
677 			}
678 			break;
679 		}
680 	}
681 
682 	if (failed) {
683 		*cause      = ROSE_OUT_OF_ORDER;
684 		*diagnostic = 0;
685 	} else {
686 		*cause      = ROSE_NOT_OBTAINABLE;
687 		*diagnostic = 0;
688 	}
689 
690 out:
691 	spin_unlock_bh(&rose_node_list_lock);
692 
693 	return res;
694 }
695 
696 /*
697  *	Handle the ioctls that control the routing functions.
698  */
699 int rose_rt_ioctl(unsigned int cmd, void __user *arg)
700 {
701 	struct rose_route_struct rose_route;
702 	struct net_device *dev;
703 	int err;
704 
705 	switch (cmd) {
706 	case SIOCADDRT:
707 		if (copy_from_user(&rose_route, arg, sizeof(struct rose_route_struct)))
708 			return -EFAULT;
709 		if ((dev = rose_ax25_dev_get(rose_route.device)) == NULL)
710 			return -EINVAL;
711 		if (rose_dev_exists(&rose_route.address)) { /* Can't add routes to ourself */
712 			dev_put(dev);
713 			return -EINVAL;
714 		}
715 		if (rose_route.mask > 10) /* Mask can't be more than 10 digits */
716 			return -EINVAL;
717 		if (rose_route.ndigis > AX25_MAX_DIGIS)
718 			return -EINVAL;
719 		err = rose_add_node(&rose_route, dev);
720 		dev_put(dev);
721 		return err;
722 
723 	case SIOCDELRT:
724 		if (copy_from_user(&rose_route, arg, sizeof(struct rose_route_struct)))
725 			return -EFAULT;
726 		if ((dev = rose_ax25_dev_get(rose_route.device)) == NULL)
727 			return -EINVAL;
728 		err = rose_del_node(&rose_route, dev);
729 		dev_put(dev);
730 		return err;
731 
732 	case SIOCRSCLRRT:
733 		return rose_clear_routes();
734 
735 	default:
736 		return -EINVAL;
737 	}
738 
739 	return 0;
740 }
741 
742 static void rose_del_route_by_neigh(struct rose_neigh *rose_neigh)
743 {
744 	struct rose_route *rose_route, *s;
745 
746 	rose_neigh->restarted = 0;
747 
748 	rose_stop_t0timer(rose_neigh);
749 	rose_start_ftimer(rose_neigh);
750 
751 	skb_queue_purge(&rose_neigh->queue);
752 
753 	spin_lock_bh(&rose_route_list_lock);
754 
755 	rose_route = rose_route_list;
756 
757 	while (rose_route != NULL) {
758 		if ((rose_route->neigh1 == rose_neigh && rose_route->neigh2 == rose_neigh) ||
759 		    (rose_route->neigh1 == rose_neigh && rose_route->neigh2 == NULL)       ||
760 		    (rose_route->neigh2 == rose_neigh && rose_route->neigh1 == NULL)) {
761 			s = rose_route->next;
762 			rose_remove_route(rose_route);
763 			rose_route = s;
764 			continue;
765 		}
766 
767 		if (rose_route->neigh1 == rose_neigh) {
768 			rose_route->neigh1->use--;
769 			rose_route->neigh1 = NULL;
770 			rose_transmit_clear_request(rose_route->neigh2, rose_route->lci2, ROSE_OUT_OF_ORDER, 0);
771 		}
772 
773 		if (rose_route->neigh2 == rose_neigh) {
774 			rose_route->neigh2->use--;
775 			rose_route->neigh2 = NULL;
776 			rose_transmit_clear_request(rose_route->neigh1, rose_route->lci1, ROSE_OUT_OF_ORDER, 0);
777 		}
778 
779 		rose_route = rose_route->next;
780 	}
781 	spin_unlock_bh(&rose_route_list_lock);
782 }
783 
784 /*
785  * 	A level 2 link has timed out, therefore it appears to be a poor link,
786  *	then don't use that neighbour until it is reset. Blow away all through
787  *	routes and connections using this route.
788  */
789 void rose_link_failed(ax25_cb *ax25, int reason)
790 {
791 	struct rose_neigh *rose_neigh;
792 
793 	spin_lock_bh(&rose_neigh_list_lock);
794 	rose_neigh = rose_neigh_list;
795 	while (rose_neigh != NULL) {
796 		if (rose_neigh->ax25 == ax25)
797 			break;
798 		rose_neigh = rose_neigh->next;
799 	}
800 
801 	if (rose_neigh != NULL) {
802 		rose_neigh->ax25 = NULL;
803 
804 		rose_del_route_by_neigh(rose_neigh);
805 		rose_kill_by_neigh(rose_neigh);
806 	}
807 	spin_unlock_bh(&rose_neigh_list_lock);
808 }
809 
810 /*
811  * 	A device has been "downed" remove its link status. Blow away all
812  *	through routes and connections that use this device.
813  */
814 void rose_link_device_down(struct net_device *dev)
815 {
816 	struct rose_neigh *rose_neigh;
817 
818 	for (rose_neigh = rose_neigh_list; rose_neigh != NULL; rose_neigh = rose_neigh->next) {
819 		if (rose_neigh->dev == dev) {
820 			rose_del_route_by_neigh(rose_neigh);
821 			rose_kill_by_neigh(rose_neigh);
822 		}
823 	}
824 }
825 
826 /*
827  *	Route a frame to an appropriate AX.25 connection.
828  */
829 int rose_route_frame(struct sk_buff *skb, ax25_cb *ax25)
830 {
831 	struct rose_neigh *rose_neigh, *new_neigh;
832 	struct rose_route *rose_route;
833 	struct rose_facilities_struct facilities;
834 	rose_address *src_addr, *dest_addr;
835 	struct sock *sk;
836 	unsigned short frametype;
837 	unsigned int lci, new_lci;
838 	unsigned char cause, diagnostic;
839 	struct net_device *dev;
840 	int len, res = 0;
841 	char buf[11];
842 
843 #if 0
844 	if (call_in_firewall(PF_ROSE, skb->dev, skb->data, NULL, &skb) != FW_ACCEPT)
845 		return res;
846 #endif
847 
848 	frametype = skb->data[2];
849 	lci = ((skb->data[0] << 8) & 0xF00) + ((skb->data[1] << 0) & 0x0FF);
850 	src_addr  = (rose_address *)(skb->data + 9);
851 	dest_addr = (rose_address *)(skb->data + 4);
852 
853 	spin_lock_bh(&rose_node_list_lock);
854 	spin_lock_bh(&rose_neigh_list_lock);
855 	spin_lock_bh(&rose_route_list_lock);
856 
857 	rose_neigh = rose_neigh_list;
858 	while (rose_neigh != NULL) {
859 		if (ax25cmp(&ax25->dest_addr, &rose_neigh->callsign) == 0 &&
860 		    ax25->ax25_dev->dev == rose_neigh->dev)
861 			break;
862 		rose_neigh = rose_neigh->next;
863 	}
864 
865 	if (rose_neigh == NULL) {
866 		printk("rose_route : unknown neighbour or device %s\n",
867 		       ax2asc(buf, &ax25->dest_addr));
868 		goto out;
869 	}
870 
871 	/*
872 	 *	Obviously the link is working, halt the ftimer.
873 	 */
874 	rose_stop_ftimer(rose_neigh);
875 
876 	/*
877 	 *	LCI of zero is always for us, and its always a restart
878 	 * 	frame.
879 	 */
880 	if (lci == 0) {
881 		rose_link_rx_restart(skb, rose_neigh, frametype);
882 		goto out;
883 	}
884 
885 	/*
886 	 *	Find an existing socket.
887 	 */
888 	if ((sk = rose_find_socket(lci, rose_neigh)) != NULL) {
889 		if (frametype == ROSE_CALL_REQUEST) {
890 			struct rose_sock *rose = rose_sk(sk);
891 
892 			/* Remove an existing unused socket */
893 			rose_clear_queues(sk);
894 			rose->cause	 = ROSE_NETWORK_CONGESTION;
895 			rose->diagnostic = 0;
896 			rose->neighbour->use--;
897 			rose->neighbour	 = NULL;
898 			rose->lci	 = 0;
899 			rose->state	 = ROSE_STATE_0;
900 			sk->sk_state	 = TCP_CLOSE;
901 			sk->sk_err	 = 0;
902 			sk->sk_shutdown	 |= SEND_SHUTDOWN;
903 			if (!sock_flag(sk, SOCK_DEAD)) {
904 				sk->sk_state_change(sk);
905 				sock_set_flag(sk, SOCK_DEAD);
906 			}
907 		}
908 		else {
909 			skb->h.raw = skb->data;
910 			res = rose_process_rx_frame(sk, skb);
911 			goto out;
912 		}
913 	}
914 
915 	/*
916 	 *	Is is a Call Request and is it for us ?
917 	 */
918 	if (frametype == ROSE_CALL_REQUEST)
919 		if ((dev = rose_dev_get(dest_addr)) != NULL) {
920 			res = rose_rx_call_request(skb, dev, rose_neigh, lci);
921 			dev_put(dev);
922 			goto out;
923 		}
924 
925 	if (!sysctl_rose_routing_control) {
926 		rose_transmit_clear_request(rose_neigh, lci, ROSE_NOT_OBTAINABLE, 0);
927 		goto out;
928 	}
929 
930 	/*
931 	 *	Route it to the next in line if we have an entry for it.
932 	 */
933 	rose_route = rose_route_list;
934 	while (rose_route != NULL) {
935 		if (rose_route->lci1 == lci &&
936 		    rose_route->neigh1 == rose_neigh) {
937 			if (frametype == ROSE_CALL_REQUEST) {
938 				/* F6FBB - Remove an existing unused route */
939 				rose_remove_route(rose_route);
940 				break;
941 			} else if (rose_route->neigh2 != NULL) {
942 				skb->data[0] &= 0xF0;
943 				skb->data[0] |= (rose_route->lci2 >> 8) & 0x0F;
944 				skb->data[1]  = (rose_route->lci2 >> 0) & 0xFF;
945 				rose_transmit_link(skb, rose_route->neigh2);
946 				if (frametype == ROSE_CLEAR_CONFIRMATION)
947 					rose_remove_route(rose_route);
948 				res = 1;
949 				goto out;
950 			} else {
951 				if (frametype == ROSE_CLEAR_CONFIRMATION)
952 					rose_remove_route(rose_route);
953 				goto out;
954 			}
955 		}
956 		if (rose_route->lci2 == lci &&
957 		    rose_route->neigh2 == rose_neigh) {
958 			if (frametype == ROSE_CALL_REQUEST) {
959 				/* F6FBB - Remove an existing unused route */
960 				rose_remove_route(rose_route);
961 				break;
962 			} else if (rose_route->neigh1 != NULL) {
963 				skb->data[0] &= 0xF0;
964 				skb->data[0] |= (rose_route->lci1 >> 8) & 0x0F;
965 				skb->data[1]  = (rose_route->lci1 >> 0) & 0xFF;
966 				rose_transmit_link(skb, rose_route->neigh1);
967 				if (frametype == ROSE_CLEAR_CONFIRMATION)
968 					rose_remove_route(rose_route);
969 				res = 1;
970 				goto out;
971 			} else {
972 				if (frametype == ROSE_CLEAR_CONFIRMATION)
973 					rose_remove_route(rose_route);
974 				goto out;
975 			}
976 		}
977 		rose_route = rose_route->next;
978 	}
979 
980 	/*
981 	 *	We know that:
982 	 *	1. The frame isn't for us,
983 	 *	2. It isn't "owned" by any existing route.
984 	 */
985 	if (frametype != ROSE_CALL_REQUEST) {	/* XXX */
986 		res = 0;
987 		goto out;
988 	}
989 
990 	len  = (((skb->data[3] >> 4) & 0x0F) + 1) / 2;
991 	len += (((skb->data[3] >> 0) & 0x0F) + 1) / 2;
992 
993 	memset(&facilities, 0x00, sizeof(struct rose_facilities_struct));
994 
995 	if (!rose_parse_facilities(skb->data + len + 4, &facilities)) {
996 		rose_transmit_clear_request(rose_neigh, lci, ROSE_INVALID_FACILITY, 76);
997 		goto out;
998 	}
999 
1000 	/*
1001 	 *	Check for routing loops.
1002 	 */
1003 	rose_route = rose_route_list;
1004 	while (rose_route != NULL) {
1005 		if (rose_route->rand == facilities.rand &&
1006 		    rosecmp(src_addr, &rose_route->src_addr) == 0 &&
1007 		    ax25cmp(&facilities.dest_call, &rose_route->src_call) == 0 &&
1008 		    ax25cmp(&facilities.source_call, &rose_route->dest_call) == 0) {
1009 			rose_transmit_clear_request(rose_neigh, lci, ROSE_NOT_OBTAINABLE, 120);
1010 			goto out;
1011 		}
1012 		rose_route = rose_route->next;
1013 	}
1014 
1015 	if ((new_neigh = rose_get_neigh(dest_addr, &cause, &diagnostic)) == NULL) {
1016 		rose_transmit_clear_request(rose_neigh, lci, cause, diagnostic);
1017 		goto out;
1018 	}
1019 
1020 	if ((new_lci = rose_new_lci(new_neigh)) == 0) {
1021 		rose_transmit_clear_request(rose_neigh, lci, ROSE_NETWORK_CONGESTION, 71);
1022 		goto out;
1023 	}
1024 
1025 	if ((rose_route = kmalloc(sizeof(*rose_route), GFP_ATOMIC)) == NULL) {
1026 		rose_transmit_clear_request(rose_neigh, lci, ROSE_NETWORK_CONGESTION, 120);
1027 		goto out;
1028 	}
1029 
1030 	rose_route->lci1      = lci;
1031 	rose_route->src_addr  = *src_addr;
1032 	rose_route->dest_addr = *dest_addr;
1033 	rose_route->src_call  = facilities.dest_call;
1034 	rose_route->dest_call = facilities.source_call;
1035 	rose_route->rand      = facilities.rand;
1036 	rose_route->neigh1    = rose_neigh;
1037 	rose_route->lci2      = new_lci;
1038 	rose_route->neigh2    = new_neigh;
1039 
1040 	rose_route->neigh1->use++;
1041 	rose_route->neigh2->use++;
1042 
1043 	rose_route->next = rose_route_list;
1044 	rose_route_list  = rose_route;
1045 
1046 	skb->data[0] &= 0xF0;
1047 	skb->data[0] |= (rose_route->lci2 >> 8) & 0x0F;
1048 	skb->data[1]  = (rose_route->lci2 >> 0) & 0xFF;
1049 
1050 	rose_transmit_link(skb, rose_route->neigh2);
1051 	res = 1;
1052 
1053 out:
1054 	spin_unlock_bh(&rose_route_list_lock);
1055 	spin_unlock_bh(&rose_neigh_list_lock);
1056 	spin_unlock_bh(&rose_node_list_lock);
1057 
1058 	return res;
1059 }
1060 
1061 #ifdef CONFIG_PROC_FS
1062 
1063 static void *rose_node_start(struct seq_file *seq, loff_t *pos)
1064 {
1065 	struct rose_node *rose_node;
1066 	int i = 1;
1067 
1068 	spin_lock_bh(&rose_neigh_list_lock);
1069 	if (*pos == 0)
1070 		return SEQ_START_TOKEN;
1071 
1072 	for (rose_node = rose_node_list; rose_node && i < *pos;
1073 	     rose_node = rose_node->next, ++i);
1074 
1075 	return (i == *pos) ? rose_node : NULL;
1076 }
1077 
1078 static void *rose_node_next(struct seq_file *seq, void *v, loff_t *pos)
1079 {
1080 	++*pos;
1081 
1082 	return (v == SEQ_START_TOKEN) ? rose_node_list
1083 		: ((struct rose_node *)v)->next;
1084 }
1085 
1086 static void rose_node_stop(struct seq_file *seq, void *v)
1087 {
1088 	spin_unlock_bh(&rose_neigh_list_lock);
1089 }
1090 
1091 static int rose_node_show(struct seq_file *seq, void *v)
1092 {
1093 	int i;
1094 
1095 	if (v == SEQ_START_TOKEN)
1096 		seq_puts(seq, "address    mask n neigh neigh neigh\n");
1097 	else {
1098 		const struct rose_node *rose_node = v;
1099 		/* if (rose_node->loopback) {
1100 			seq_printf(seq, "%-10s %04d 1 loopback\n",
1101 				rose2asc(&rose_node->address),
1102 				rose_node->mask);
1103 		} else { */
1104 			seq_printf(seq, "%-10s %04d %d",
1105 				rose2asc(&rose_node->address),
1106 				rose_node->mask,
1107 				rose_node->count);
1108 
1109 			for (i = 0; i < rose_node->count; i++)
1110 				seq_printf(seq, " %05d",
1111 					rose_node->neighbour[i]->number);
1112 
1113 			seq_puts(seq, "\n");
1114 		/* } */
1115 	}
1116 	return 0;
1117 }
1118 
1119 static struct seq_operations rose_node_seqops = {
1120 	.start = rose_node_start,
1121 	.next = rose_node_next,
1122 	.stop = rose_node_stop,
1123 	.show = rose_node_show,
1124 };
1125 
1126 static int rose_nodes_open(struct inode *inode, struct file *file)
1127 {
1128 	return seq_open(file, &rose_node_seqops);
1129 }
1130 
1131 const struct file_operations rose_nodes_fops = {
1132 	.owner = THIS_MODULE,
1133 	.open = rose_nodes_open,
1134 	.read = seq_read,
1135 	.llseek = seq_lseek,
1136 	.release = seq_release,
1137 };
1138 
1139 static void *rose_neigh_start(struct seq_file *seq, loff_t *pos)
1140 {
1141 	struct rose_neigh *rose_neigh;
1142 	int i = 1;
1143 
1144 	spin_lock_bh(&rose_neigh_list_lock);
1145 	if (*pos == 0)
1146 		return SEQ_START_TOKEN;
1147 
1148 	for (rose_neigh = rose_neigh_list; rose_neigh && i < *pos;
1149 	     rose_neigh = rose_neigh->next, ++i);
1150 
1151 	return (i == *pos) ? rose_neigh : NULL;
1152 }
1153 
1154 static void *rose_neigh_next(struct seq_file *seq, void *v, loff_t *pos)
1155 {
1156 	++*pos;
1157 
1158 	return (v == SEQ_START_TOKEN) ? rose_neigh_list
1159 		: ((struct rose_neigh *)v)->next;
1160 }
1161 
1162 static void rose_neigh_stop(struct seq_file *seq, void *v)
1163 {
1164 	spin_unlock_bh(&rose_neigh_list_lock);
1165 }
1166 
1167 static int rose_neigh_show(struct seq_file *seq, void *v)
1168 {
1169 	char buf[11];
1170 	int i;
1171 
1172 	if (v == SEQ_START_TOKEN)
1173 		seq_puts(seq,
1174 			 "addr  callsign  dev  count use mode restart  t0  tf digipeaters\n");
1175 	else {
1176 		struct rose_neigh *rose_neigh = v;
1177 
1178 		/* if (!rose_neigh->loopback) { */
1179 		seq_printf(seq, "%05d %-9s %-4s   %3d %3d  %3s     %3s %3lu %3lu",
1180 			   rose_neigh->number,
1181 			   (rose_neigh->loopback) ? "RSLOOP-0" : ax2asc(buf, &rose_neigh->callsign),
1182 			   rose_neigh->dev ? rose_neigh->dev->name : "???",
1183 			   rose_neigh->count,
1184 			   rose_neigh->use,
1185 			   (rose_neigh->dce_mode) ? "DCE" : "DTE",
1186 			   (rose_neigh->restarted) ? "yes" : "no",
1187 			   ax25_display_timer(&rose_neigh->t0timer) / HZ,
1188 			   ax25_display_timer(&rose_neigh->ftimer)  / HZ);
1189 
1190 		if (rose_neigh->digipeat != NULL) {
1191 			for (i = 0; i < rose_neigh->digipeat->ndigi; i++)
1192 				seq_printf(seq, " %s", ax2asc(buf, &rose_neigh->digipeat->calls[i]));
1193 		}
1194 
1195 		seq_puts(seq, "\n");
1196 	}
1197 	return 0;
1198 }
1199 
1200 
1201 static struct seq_operations rose_neigh_seqops = {
1202 	.start = rose_neigh_start,
1203 	.next = rose_neigh_next,
1204 	.stop = rose_neigh_stop,
1205 	.show = rose_neigh_show,
1206 };
1207 
1208 static int rose_neigh_open(struct inode *inode, struct file *file)
1209 {
1210 	return seq_open(file, &rose_neigh_seqops);
1211 }
1212 
1213 const struct file_operations rose_neigh_fops = {
1214 	.owner = THIS_MODULE,
1215 	.open = rose_neigh_open,
1216 	.read = seq_read,
1217 	.llseek = seq_lseek,
1218 	.release = seq_release,
1219 };
1220 
1221 
1222 static void *rose_route_start(struct seq_file *seq, loff_t *pos)
1223 {
1224 	struct rose_route *rose_route;
1225 	int i = 1;
1226 
1227 	spin_lock_bh(&rose_route_list_lock);
1228 	if (*pos == 0)
1229 		return SEQ_START_TOKEN;
1230 
1231 	for (rose_route = rose_route_list; rose_route && i < *pos;
1232 	     rose_route = rose_route->next, ++i);
1233 
1234 	return (i == *pos) ? rose_route : NULL;
1235 }
1236 
1237 static void *rose_route_next(struct seq_file *seq, void *v, loff_t *pos)
1238 {
1239 	++*pos;
1240 
1241 	return (v == SEQ_START_TOKEN) ? rose_route_list
1242 		: ((struct rose_route *)v)->next;
1243 }
1244 
1245 static void rose_route_stop(struct seq_file *seq, void *v)
1246 {
1247 	spin_unlock_bh(&rose_route_list_lock);
1248 }
1249 
1250 static int rose_route_show(struct seq_file *seq, void *v)
1251 {
1252 	char buf[11];
1253 
1254 	if (v == SEQ_START_TOKEN)
1255 		seq_puts(seq,
1256 			 "lci  address     callsign   neigh  <-> lci  address     callsign   neigh\n");
1257 	else {
1258 		struct rose_route *rose_route = v;
1259 
1260 		if (rose_route->neigh1)
1261 			seq_printf(seq,
1262 				   "%3.3X  %-10s  %-9s  %05d      ",
1263 				   rose_route->lci1,
1264 				   rose2asc(&rose_route->src_addr),
1265 				   ax2asc(buf, &rose_route->src_call),
1266 				   rose_route->neigh1->number);
1267 		else
1268 			seq_puts(seq,
1269 				 "000  *           *          00000      ");
1270 
1271 		if (rose_route->neigh2)
1272 			seq_printf(seq,
1273 				   "%3.3X  %-10s  %-9s  %05d\n",
1274 				rose_route->lci2,
1275 				rose2asc(&rose_route->dest_addr),
1276 				ax2asc(buf, &rose_route->dest_call),
1277 				rose_route->neigh2->number);
1278 		 else
1279 			 seq_puts(seq,
1280 				  "000  *           *          00000\n");
1281 		}
1282 	return 0;
1283 }
1284 
1285 static struct seq_operations rose_route_seqops = {
1286 	.start = rose_route_start,
1287 	.next = rose_route_next,
1288 	.stop = rose_route_stop,
1289 	.show = rose_route_show,
1290 };
1291 
1292 static int rose_route_open(struct inode *inode, struct file *file)
1293 {
1294 	return seq_open(file, &rose_route_seqops);
1295 }
1296 
1297 const struct file_operations rose_routes_fops = {
1298 	.owner = THIS_MODULE,
1299 	.open = rose_route_open,
1300 	.read = seq_read,
1301 	.llseek = seq_lseek,
1302 	.release = seq_release,
1303 };
1304 
1305 #endif /* CONFIG_PROC_FS */
1306 
1307 /*
1308  *	Release all memory associated with ROSE routing structures.
1309  */
1310 void __exit rose_rt_free(void)
1311 {
1312 	struct rose_neigh *s, *rose_neigh = rose_neigh_list;
1313 	struct rose_node  *t, *rose_node  = rose_node_list;
1314 	struct rose_route *u, *rose_route = rose_route_list;
1315 
1316 	while (rose_neigh != NULL) {
1317 		s          = rose_neigh;
1318 		rose_neigh = rose_neigh->next;
1319 
1320 		rose_remove_neigh(s);
1321 	}
1322 
1323 	while (rose_node != NULL) {
1324 		t         = rose_node;
1325 		rose_node = rose_node->next;
1326 
1327 		rose_remove_node(t);
1328 	}
1329 
1330 	while (rose_route != NULL) {
1331 		u          = rose_route;
1332 		rose_route = rose_route->next;
1333 
1334 		rose_remove_route(u);
1335 	}
1336 }
1337