xref: /linux/net/rose/rose_route.c (revision 93d90ad708b8da6efc0e487b66111aa9db7f70c7)
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 <linux/slab.h>
20 #include <net/ax25.h>
21 #include <linux/inet.h>
22 #include <linux/netdevice.h>
23 #include <net/arp.h>
24 #include <linux/if_arp.h>
25 #include <linux/skbuff.h>
26 #include <net/sock.h>
27 #include <net/tcp_states.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 #include <linux/export.h>
39 
40 static unsigned int rose_neigh_no = 1;
41 
42 static struct rose_node  *rose_node_list;
43 static DEFINE_SPINLOCK(rose_node_list_lock);
44 static struct rose_neigh *rose_neigh_list;
45 static DEFINE_SPINLOCK(rose_neigh_list_lock);
46 static struct rose_route *rose_route_list;
47 static DEFINE_SPINLOCK(rose_route_list_lock);
48 
49 struct rose_neigh *rose_loopback_neigh;
50 
51 /*
52  *	Add a new route to a node, and in the process add the node and the
53  *	neighbour if it is new.
54  */
55 static int __must_check rose_add_node(struct rose_route_struct *rose_route,
56 	struct net_device *dev)
57 {
58 	struct rose_node  *rose_node, *rose_tmpn, *rose_tmpp;
59 	struct rose_neigh *rose_neigh;
60 	int i, res = 0;
61 
62 	spin_lock_bh(&rose_node_list_lock);
63 	spin_lock_bh(&rose_neigh_list_lock);
64 
65 	rose_node = rose_node_list;
66 	while (rose_node != NULL) {
67 		if ((rose_node->mask == rose_route->mask) &&
68 		    (rosecmpm(&rose_route->address, &rose_node->address,
69 			      rose_route->mask) == 0))
70 			break;
71 		rose_node = rose_node->next;
72 	}
73 
74 	if (rose_node != NULL && rose_node->loopback) {
75 		res = -EINVAL;
76 		goto out;
77 	}
78 
79 	rose_neigh = rose_neigh_list;
80 	while (rose_neigh != NULL) {
81 		if (ax25cmp(&rose_route->neighbour,
82 			    &rose_neigh->callsign) == 0 &&
83 		    rose_neigh->dev == dev)
84 			break;
85 		rose_neigh = rose_neigh->next;
86 	}
87 
88 	if (rose_neigh == NULL) {
89 		rose_neigh = kmalloc(sizeof(*rose_neigh), GFP_ATOMIC);
90 		if (rose_neigh == NULL) {
91 			res = -ENOMEM;
92 			goto out;
93 		}
94 
95 		rose_neigh->callsign  = rose_route->neighbour;
96 		rose_neigh->digipeat  = NULL;
97 		rose_neigh->ax25      = NULL;
98 		rose_neigh->dev       = dev;
99 		rose_neigh->count     = 0;
100 		rose_neigh->use       = 0;
101 		rose_neigh->dce_mode  = 0;
102 		rose_neigh->loopback  = 0;
103 		rose_neigh->number    = rose_neigh_no++;
104 		rose_neigh->restarted = 0;
105 
106 		skb_queue_head_init(&rose_neigh->queue);
107 
108 		init_timer(&rose_neigh->ftimer);
109 		init_timer(&rose_neigh->t0timer);
110 
111 		if (rose_route->ndigis != 0) {
112 			rose_neigh->digipeat =
113 				kmalloc(sizeof(ax25_digi), GFP_ATOMIC);
114 			if (rose_neigh->digipeat == NULL) {
115 				kfree(rose_neigh);
116 				res = -ENOMEM;
117 				goto out;
118 			}
119 
120 			rose_neigh->digipeat->ndigi      = rose_route->ndigis;
121 			rose_neigh->digipeat->lastrepeat = -1;
122 
123 			for (i = 0; i < rose_route->ndigis; i++) {
124 				rose_neigh->digipeat->calls[i]    =
125 					rose_route->digipeaters[i];
126 				rose_neigh->digipeat->repeated[i] = 0;
127 			}
128 		}
129 
130 		rose_neigh->next = rose_neigh_list;
131 		rose_neigh_list  = rose_neigh;
132 	}
133 
134 	/*
135 	 * This is a new node to be inserted into the list. Find where it needs
136 	 * to be inserted into the list, and insert it. We want to be sure
137 	 * to order the list in descending order of mask size to ensure that
138 	 * later when we are searching this list the first match will be the
139 	 * best match.
140 	 */
141 	if (rose_node == NULL) {
142 		rose_tmpn = rose_node_list;
143 		rose_tmpp = NULL;
144 
145 		while (rose_tmpn != NULL) {
146 			if (rose_tmpn->mask > rose_route->mask) {
147 				rose_tmpp = rose_tmpn;
148 				rose_tmpn = rose_tmpn->next;
149 			} else {
150 				break;
151 			}
152 		}
153 
154 		/* create new node */
155 		rose_node = kmalloc(sizeof(*rose_node), GFP_ATOMIC);
156 		if (rose_node == NULL) {
157 			res = -ENOMEM;
158 			goto out;
159 		}
160 
161 		rose_node->address      = rose_route->address;
162 		rose_node->mask         = rose_route->mask;
163 		rose_node->count        = 1;
164 		rose_node->loopback     = 0;
165 		rose_node->neighbour[0] = rose_neigh;
166 
167 		if (rose_tmpn == NULL) {
168 			if (rose_tmpp == NULL) {	/* Empty list */
169 				rose_node_list  = rose_node;
170 				rose_node->next = NULL;
171 			} else {
172 				rose_tmpp->next = rose_node;
173 				rose_node->next = NULL;
174 			}
175 		} else {
176 			if (rose_tmpp == NULL) {	/* 1st node */
177 				rose_node->next = rose_node_list;
178 				rose_node_list  = rose_node;
179 			} else {
180 				rose_tmpp->next = rose_node;
181 				rose_node->next = rose_tmpn;
182 			}
183 		}
184 		rose_neigh->count++;
185 
186 		goto out;
187 	}
188 
189 	/* We have space, slot it in */
190 	if (rose_node->count < 3) {
191 		rose_node->neighbour[rose_node->count] = rose_neigh;
192 		rose_node->count++;
193 		rose_neigh->count++;
194 	}
195 
196 out:
197 	spin_unlock_bh(&rose_neigh_list_lock);
198 	spin_unlock_bh(&rose_node_list_lock);
199 
200 	return res;
201 }
202 
203 /*
204  * Caller is holding rose_node_list_lock.
205  */
206 static void rose_remove_node(struct rose_node *rose_node)
207 {
208 	struct rose_node *s;
209 
210 	if ((s = rose_node_list) == rose_node) {
211 		rose_node_list = rose_node->next;
212 		kfree(rose_node);
213 		return;
214 	}
215 
216 	while (s != NULL && s->next != NULL) {
217 		if (s->next == rose_node) {
218 			s->next = rose_node->next;
219 			kfree(rose_node);
220 			return;
221 		}
222 
223 		s = s->next;
224 	}
225 }
226 
227 /*
228  * Caller is holding rose_neigh_list_lock.
229  */
230 static void rose_remove_neigh(struct rose_neigh *rose_neigh)
231 {
232 	struct rose_neigh *s;
233 
234 	rose_stop_ftimer(rose_neigh);
235 	rose_stop_t0timer(rose_neigh);
236 
237 	skb_queue_purge(&rose_neigh->queue);
238 
239 	if ((s = rose_neigh_list) == rose_neigh) {
240 		rose_neigh_list = rose_neigh->next;
241 		if (rose_neigh->ax25)
242 			ax25_cb_put(rose_neigh->ax25);
243 		kfree(rose_neigh->digipeat);
244 		kfree(rose_neigh);
245 		return;
246 	}
247 
248 	while (s != NULL && s->next != NULL) {
249 		if (s->next == rose_neigh) {
250 			s->next = rose_neigh->next;
251 			if (rose_neigh->ax25)
252 				ax25_cb_put(rose_neigh->ax25);
253 			kfree(rose_neigh->digipeat);
254 			kfree(rose_neigh);
255 			return;
256 		}
257 
258 		s = s->next;
259 	}
260 }
261 
262 /*
263  * Caller is holding rose_route_list_lock.
264  */
265 static void rose_remove_route(struct rose_route *rose_route)
266 {
267 	struct rose_route *s;
268 
269 	if (rose_route->neigh1 != NULL)
270 		rose_route->neigh1->use--;
271 
272 	if (rose_route->neigh2 != NULL)
273 		rose_route->neigh2->use--;
274 
275 	if ((s = rose_route_list) == rose_route) {
276 		rose_route_list = rose_route->next;
277 		kfree(rose_route);
278 		return;
279 	}
280 
281 	while (s != NULL && s->next != NULL) {
282 		if (s->next == rose_route) {
283 			s->next = rose_route->next;
284 			kfree(rose_route);
285 			return;
286 		}
287 
288 		s = s->next;
289 	}
290 }
291 
292 /*
293  *	"Delete" a node. Strictly speaking remove a route to a node. The node
294  *	is only deleted if no routes are left to it.
295  */
296 static int rose_del_node(struct rose_route_struct *rose_route,
297 	struct net_device *dev)
298 {
299 	struct rose_node  *rose_node;
300 	struct rose_neigh *rose_neigh;
301 	int i, err = 0;
302 
303 	spin_lock_bh(&rose_node_list_lock);
304 	spin_lock_bh(&rose_neigh_list_lock);
305 
306 	rose_node = rose_node_list;
307 	while (rose_node != NULL) {
308 		if ((rose_node->mask == rose_route->mask) &&
309 		    (rosecmpm(&rose_route->address, &rose_node->address,
310 			      rose_route->mask) == 0))
311 			break;
312 		rose_node = rose_node->next;
313 	}
314 
315 	if (rose_node == NULL || rose_node->loopback) {
316 		err = -EINVAL;
317 		goto out;
318 	}
319 
320 	rose_neigh = rose_neigh_list;
321 	while (rose_neigh != NULL) {
322 		if (ax25cmp(&rose_route->neighbour,
323 			    &rose_neigh->callsign) == 0 &&
324 		    rose_neigh->dev == dev)
325 			break;
326 		rose_neigh = rose_neigh->next;
327 	}
328 
329 	if (rose_neigh == NULL) {
330 		err = -EINVAL;
331 		goto out;
332 	}
333 
334 	for (i = 0; i < rose_node->count; i++) {
335 		if (rose_node->neighbour[i] == rose_neigh) {
336 			rose_neigh->count--;
337 
338 			if (rose_neigh->count == 0 && rose_neigh->use == 0)
339 				rose_remove_neigh(rose_neigh);
340 
341 			rose_node->count--;
342 
343 			if (rose_node->count == 0) {
344 				rose_remove_node(rose_node);
345 			} else {
346 				switch (i) {
347 				case 0:
348 					rose_node->neighbour[0] =
349 						rose_node->neighbour[1];
350 				case 1:
351 					rose_node->neighbour[1] =
352 						rose_node->neighbour[2];
353 				case 2:
354 					break;
355 				}
356 			}
357 			goto out;
358 		}
359 	}
360 	err = -EINVAL;
361 
362 out:
363 	spin_unlock_bh(&rose_neigh_list_lock);
364 	spin_unlock_bh(&rose_node_list_lock);
365 
366 	return err;
367 }
368 
369 /*
370  *	Add the loopback neighbour.
371  */
372 void rose_add_loopback_neigh(void)
373 {
374 	struct rose_neigh *sn;
375 
376 	rose_loopback_neigh = kmalloc(sizeof(struct rose_neigh), GFP_KERNEL);
377 	if (!rose_loopback_neigh)
378 		return;
379 	sn = rose_loopback_neigh;
380 
381 	sn->callsign  = null_ax25_address;
382 	sn->digipeat  = NULL;
383 	sn->ax25      = NULL;
384 	sn->dev       = NULL;
385 	sn->count     = 0;
386 	sn->use       = 0;
387 	sn->dce_mode  = 1;
388 	sn->loopback  = 1;
389 	sn->number    = rose_neigh_no++;
390 	sn->restarted = 1;
391 
392 	skb_queue_head_init(&sn->queue);
393 
394 	init_timer(&sn->ftimer);
395 	init_timer(&sn->t0timer);
396 
397 	spin_lock_bh(&rose_neigh_list_lock);
398 	sn->next = rose_neigh_list;
399 	rose_neigh_list           = sn;
400 	spin_unlock_bh(&rose_neigh_list_lock);
401 }
402 
403 /*
404  *	Add a loopback node.
405  */
406 int rose_add_loopback_node(rose_address *address)
407 {
408 	struct rose_node *rose_node;
409 	int err = 0;
410 
411 	spin_lock_bh(&rose_node_list_lock);
412 
413 	rose_node = rose_node_list;
414 	while (rose_node != NULL) {
415 		if ((rose_node->mask == 10) &&
416 		     (rosecmpm(address, &rose_node->address, 10) == 0) &&
417 		     rose_node->loopback)
418 			break;
419 		rose_node = rose_node->next;
420 	}
421 
422 	if (rose_node != NULL)
423 		goto out;
424 
425 	if ((rose_node = kmalloc(sizeof(*rose_node), GFP_ATOMIC)) == NULL) {
426 		err = -ENOMEM;
427 		goto out;
428 	}
429 
430 	rose_node->address      = *address;
431 	rose_node->mask         = 10;
432 	rose_node->count        = 1;
433 	rose_node->loopback     = 1;
434 	rose_node->neighbour[0] = rose_loopback_neigh;
435 
436 	/* Insert at the head of list. Address is always mask=10 */
437 	rose_node->next = rose_node_list;
438 	rose_node_list  = rose_node;
439 
440 	rose_loopback_neigh->count++;
441 
442 out:
443 	spin_unlock_bh(&rose_node_list_lock);
444 
445 	return err;
446 }
447 
448 /*
449  *	Delete a loopback node.
450  */
451 void rose_del_loopback_node(rose_address *address)
452 {
453 	struct rose_node *rose_node;
454 
455 	spin_lock_bh(&rose_node_list_lock);
456 
457 	rose_node = rose_node_list;
458 	while (rose_node != NULL) {
459 		if ((rose_node->mask == 10) &&
460 		    (rosecmpm(address, &rose_node->address, 10) == 0) &&
461 		    rose_node->loopback)
462 			break;
463 		rose_node = rose_node->next;
464 	}
465 
466 	if (rose_node == NULL)
467 		goto out;
468 
469 	rose_remove_node(rose_node);
470 
471 	rose_loopback_neigh->count--;
472 
473 out:
474 	spin_unlock_bh(&rose_node_list_lock);
475 }
476 
477 /*
478  *	A device has been removed. Remove its routes and neighbours.
479  */
480 void rose_rt_device_down(struct net_device *dev)
481 {
482 	struct rose_neigh *s, *rose_neigh;
483 	struct rose_node  *t, *rose_node;
484 	int i;
485 
486 	spin_lock_bh(&rose_node_list_lock);
487 	spin_lock_bh(&rose_neigh_list_lock);
488 	rose_neigh = rose_neigh_list;
489 	while (rose_neigh != NULL) {
490 		s          = rose_neigh;
491 		rose_neigh = rose_neigh->next;
492 
493 		if (s->dev != dev)
494 			continue;
495 
496 		rose_node = rose_node_list;
497 
498 		while (rose_node != NULL) {
499 			t         = rose_node;
500 			rose_node = rose_node->next;
501 
502 			for (i = 0; i < t->count; i++) {
503 				if (t->neighbour[i] != s)
504 					continue;
505 
506 				t->count--;
507 
508 				switch (i) {
509 				case 0:
510 					t->neighbour[0] = t->neighbour[1];
511 				case 1:
512 					t->neighbour[1] = t->neighbour[2];
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 && rosecmp(addr, (rose_address *)dev->dev_addr) == 0) {
633 			dev_hold(dev);
634 			goto out;
635 		}
636 	}
637 	dev = NULL;
638 out:
639 	rcu_read_unlock();
640 	return dev;
641 }
642 
643 static int rose_dev_exists(rose_address *addr)
644 {
645 	struct net_device *dev;
646 
647 	rcu_read_lock();
648 	for_each_netdev_rcu(&init_net, dev) {
649 		if ((dev->flags & IFF_UP) && dev->type == ARPHRD_ROSE && rosecmp(addr, (rose_address *)dev->dev_addr) == 0)
650 			goto out;
651 	}
652 	dev = NULL;
653 out:
654 	rcu_read_unlock();
655 	return dev != NULL;
656 }
657 
658 
659 
660 
661 struct rose_route *rose_route_free_lci(unsigned int lci, struct rose_neigh *neigh)
662 {
663 	struct rose_route *rose_route;
664 
665 	for (rose_route = rose_route_list; rose_route != NULL; rose_route = rose_route->next)
666 		if ((rose_route->neigh1 == neigh && rose_route->lci1 == lci) ||
667 		    (rose_route->neigh2 == neigh && rose_route->lci2 == lci))
668 			return rose_route;
669 
670 	return NULL;
671 }
672 
673 /*
674  *	Find a neighbour or a route given a ROSE address.
675  */
676 struct rose_neigh *rose_get_neigh(rose_address *addr, unsigned char *cause,
677 	unsigned char *diagnostic, int route_frame)
678 {
679 	struct rose_neigh *res = NULL;
680 	struct rose_node *node;
681 	int failed = 0;
682 	int i;
683 
684 	if (!route_frame) spin_lock_bh(&rose_node_list_lock);
685 	for (node = rose_node_list; node != NULL; node = node->next) {
686 		if (rosecmpm(addr, &node->address, node->mask) == 0) {
687 			for (i = 0; i < node->count; i++) {
688 				if (node->neighbour[i]->restarted) {
689 					res = node->neighbour[i];
690 					goto out;
691 				}
692 			}
693 		}
694 	}
695 	if (!route_frame) { /* connect request */
696 		for (node = rose_node_list; node != NULL; node = node->next) {
697 			if (rosecmpm(addr, &node->address, node->mask) == 0) {
698 				for (i = 0; i < node->count; i++) {
699 					if (!rose_ftimer_running(node->neighbour[i])) {
700 						res = node->neighbour[i];
701 						failed = 0;
702 						goto out;
703 					}
704 					failed = 1;
705 				}
706 			}
707 		}
708 	}
709 
710 	if (failed) {
711 		*cause      = ROSE_OUT_OF_ORDER;
712 		*diagnostic = 0;
713 	} else {
714 		*cause      = ROSE_NOT_OBTAINABLE;
715 		*diagnostic = 0;
716 	}
717 
718 out:
719 	if (!route_frame) spin_unlock_bh(&rose_node_list_lock);
720 	return res;
721 }
722 
723 /*
724  *	Handle the ioctls that control the routing functions.
725  */
726 int rose_rt_ioctl(unsigned int cmd, void __user *arg)
727 {
728 	struct rose_route_struct rose_route;
729 	struct net_device *dev;
730 	int err;
731 
732 	switch (cmd) {
733 	case SIOCADDRT:
734 		if (copy_from_user(&rose_route, arg, sizeof(struct rose_route_struct)))
735 			return -EFAULT;
736 		if ((dev = rose_ax25_dev_find(rose_route.device)) == NULL)
737 			return -EINVAL;
738 		if (rose_dev_exists(&rose_route.address)) /* Can't add routes to ourself */
739 			return -EINVAL;
740 		if (rose_route.mask > 10) /* Mask can't be more than 10 digits */
741 			return -EINVAL;
742 		if (rose_route.ndigis > AX25_MAX_DIGIS)
743 			return -EINVAL;
744 		err = rose_add_node(&rose_route, dev);
745 		return err;
746 
747 	case SIOCDELRT:
748 		if (copy_from_user(&rose_route, arg, sizeof(struct rose_route_struct)))
749 			return -EFAULT;
750 		if ((dev = rose_ax25_dev_find(rose_route.device)) == NULL)
751 			return -EINVAL;
752 		err = rose_del_node(&rose_route, dev);
753 		return err;
754 
755 	case SIOCRSCLRRT:
756 		return rose_clear_routes();
757 
758 	default:
759 		return -EINVAL;
760 	}
761 
762 	return 0;
763 }
764 
765 static void rose_del_route_by_neigh(struct rose_neigh *rose_neigh)
766 {
767 	struct rose_route *rose_route, *s;
768 
769 	rose_neigh->restarted = 0;
770 
771 	rose_stop_t0timer(rose_neigh);
772 	rose_start_ftimer(rose_neigh);
773 
774 	skb_queue_purge(&rose_neigh->queue);
775 
776 	spin_lock_bh(&rose_route_list_lock);
777 
778 	rose_route = rose_route_list;
779 
780 	while (rose_route != NULL) {
781 		if ((rose_route->neigh1 == rose_neigh && rose_route->neigh2 == rose_neigh) ||
782 		    (rose_route->neigh1 == rose_neigh && rose_route->neigh2 == NULL)       ||
783 		    (rose_route->neigh2 == rose_neigh && rose_route->neigh1 == NULL)) {
784 			s = rose_route->next;
785 			rose_remove_route(rose_route);
786 			rose_route = s;
787 			continue;
788 		}
789 
790 		if (rose_route->neigh1 == rose_neigh) {
791 			rose_route->neigh1->use--;
792 			rose_route->neigh1 = NULL;
793 			rose_transmit_clear_request(rose_route->neigh2, rose_route->lci2, ROSE_OUT_OF_ORDER, 0);
794 		}
795 
796 		if (rose_route->neigh2 == rose_neigh) {
797 			rose_route->neigh2->use--;
798 			rose_route->neigh2 = NULL;
799 			rose_transmit_clear_request(rose_route->neigh1, rose_route->lci1, ROSE_OUT_OF_ORDER, 0);
800 		}
801 
802 		rose_route = rose_route->next;
803 	}
804 	spin_unlock_bh(&rose_route_list_lock);
805 }
806 
807 /*
808  * 	A level 2 link has timed out, therefore it appears to be a poor link,
809  *	then don't use that neighbour until it is reset. Blow away all through
810  *	routes and connections using this route.
811  */
812 void rose_link_failed(ax25_cb *ax25, int reason)
813 {
814 	struct rose_neigh *rose_neigh;
815 
816 	spin_lock_bh(&rose_neigh_list_lock);
817 	rose_neigh = rose_neigh_list;
818 	while (rose_neigh != NULL) {
819 		if (rose_neigh->ax25 == ax25)
820 			break;
821 		rose_neigh = rose_neigh->next;
822 	}
823 
824 	if (rose_neigh != NULL) {
825 		rose_neigh->ax25 = NULL;
826 		ax25_cb_put(ax25);
827 
828 		rose_del_route_by_neigh(rose_neigh);
829 		rose_kill_by_neigh(rose_neigh);
830 	}
831 	spin_unlock_bh(&rose_neigh_list_lock);
832 }
833 
834 /*
835  * 	A device has been "downed" remove its link status. Blow away all
836  *	through routes and connections that use this device.
837  */
838 void rose_link_device_down(struct net_device *dev)
839 {
840 	struct rose_neigh *rose_neigh;
841 
842 	for (rose_neigh = rose_neigh_list; rose_neigh != NULL; rose_neigh = rose_neigh->next) {
843 		if (rose_neigh->dev == dev) {
844 			rose_del_route_by_neigh(rose_neigh);
845 			rose_kill_by_neigh(rose_neigh);
846 		}
847 	}
848 }
849 
850 /*
851  *	Route a frame to an appropriate AX.25 connection.
852  */
853 int rose_route_frame(struct sk_buff *skb, ax25_cb *ax25)
854 {
855 	struct rose_neigh *rose_neigh, *new_neigh;
856 	struct rose_route *rose_route;
857 	struct rose_facilities_struct facilities;
858 	rose_address *src_addr, *dest_addr;
859 	struct sock *sk;
860 	unsigned short frametype;
861 	unsigned int lci, new_lci;
862 	unsigned char cause, diagnostic;
863 	struct net_device *dev;
864 	int res = 0;
865 	char buf[11];
866 
867 	if (skb->len < ROSE_MIN_LEN)
868 		return res;
869 	frametype = skb->data[2];
870 	lci = ((skb->data[0] << 8) & 0xF00) + ((skb->data[1] << 0) & 0x0FF);
871 	if (frametype == ROSE_CALL_REQUEST &&
872 	    (skb->len <= ROSE_CALL_REQ_FACILITIES_OFF ||
873 	     skb->data[ROSE_CALL_REQ_ADDR_LEN_OFF] !=
874 	     ROSE_CALL_REQ_ADDR_LEN_VAL))
875 		return res;
876 	src_addr  = (rose_address *)(skb->data + ROSE_CALL_REQ_SRC_ADDR_OFF);
877 	dest_addr = (rose_address *)(skb->data + ROSE_CALL_REQ_DEST_ADDR_OFF);
878 
879 	spin_lock_bh(&rose_neigh_list_lock);
880 	spin_lock_bh(&rose_route_list_lock);
881 
882 	rose_neigh = rose_neigh_list;
883 	while (rose_neigh != NULL) {
884 		if (ax25cmp(&ax25->dest_addr, &rose_neigh->callsign) == 0 &&
885 		    ax25->ax25_dev->dev == rose_neigh->dev)
886 			break;
887 		rose_neigh = rose_neigh->next;
888 	}
889 
890 	if (rose_neigh == NULL) {
891 		printk("rose_route : unknown neighbour or device %s\n",
892 		       ax2asc(buf, &ax25->dest_addr));
893 		goto out;
894 	}
895 
896 	/*
897 	 *	Obviously the link is working, halt the ftimer.
898 	 */
899 	rose_stop_ftimer(rose_neigh);
900 
901 	/*
902 	 *	LCI of zero is always for us, and its always a restart
903 	 * 	frame.
904 	 */
905 	if (lci == 0) {
906 		rose_link_rx_restart(skb, rose_neigh, frametype);
907 		goto out;
908 	}
909 
910 	/*
911 	 *	Find an existing socket.
912 	 */
913 	if ((sk = rose_find_socket(lci, rose_neigh)) != NULL) {
914 		if (frametype == ROSE_CALL_REQUEST) {
915 			struct rose_sock *rose = rose_sk(sk);
916 
917 			/* Remove an existing unused socket */
918 			rose_clear_queues(sk);
919 			rose->cause	 = ROSE_NETWORK_CONGESTION;
920 			rose->diagnostic = 0;
921 			rose->neighbour->use--;
922 			rose->neighbour	 = NULL;
923 			rose->lci	 = 0;
924 			rose->state	 = ROSE_STATE_0;
925 			sk->sk_state	 = TCP_CLOSE;
926 			sk->sk_err	 = 0;
927 			sk->sk_shutdown	 |= SEND_SHUTDOWN;
928 			if (!sock_flag(sk, SOCK_DEAD)) {
929 				sk->sk_state_change(sk);
930 				sock_set_flag(sk, SOCK_DEAD);
931 			}
932 		}
933 		else {
934 			skb_reset_transport_header(skb);
935 			res = rose_process_rx_frame(sk, skb);
936 			goto out;
937 		}
938 	}
939 
940 	/*
941 	 *	Is is a Call Request and is it for us ?
942 	 */
943 	if (frametype == ROSE_CALL_REQUEST)
944 		if ((dev = rose_dev_get(dest_addr)) != NULL) {
945 			res = rose_rx_call_request(skb, dev, rose_neigh, lci);
946 			dev_put(dev);
947 			goto out;
948 		}
949 
950 	if (!sysctl_rose_routing_control) {
951 		rose_transmit_clear_request(rose_neigh, lci, ROSE_NOT_OBTAINABLE, 0);
952 		goto out;
953 	}
954 
955 	/*
956 	 *	Route it to the next in line if we have an entry for it.
957 	 */
958 	rose_route = rose_route_list;
959 	while (rose_route != NULL) {
960 		if (rose_route->lci1 == lci &&
961 		    rose_route->neigh1 == rose_neigh) {
962 			if (frametype == ROSE_CALL_REQUEST) {
963 				/* F6FBB - Remove an existing unused route */
964 				rose_remove_route(rose_route);
965 				break;
966 			} else if (rose_route->neigh2 != NULL) {
967 				skb->data[0] &= 0xF0;
968 				skb->data[0] |= (rose_route->lci2 >> 8) & 0x0F;
969 				skb->data[1]  = (rose_route->lci2 >> 0) & 0xFF;
970 				rose_transmit_link(skb, rose_route->neigh2);
971 				if (frametype == ROSE_CLEAR_CONFIRMATION)
972 					rose_remove_route(rose_route);
973 				res = 1;
974 				goto out;
975 			} else {
976 				if (frametype == ROSE_CLEAR_CONFIRMATION)
977 					rose_remove_route(rose_route);
978 				goto out;
979 			}
980 		}
981 		if (rose_route->lci2 == lci &&
982 		    rose_route->neigh2 == rose_neigh) {
983 			if (frametype == ROSE_CALL_REQUEST) {
984 				/* F6FBB - Remove an existing unused route */
985 				rose_remove_route(rose_route);
986 				break;
987 			} else if (rose_route->neigh1 != NULL) {
988 				skb->data[0] &= 0xF0;
989 				skb->data[0] |= (rose_route->lci1 >> 8) & 0x0F;
990 				skb->data[1]  = (rose_route->lci1 >> 0) & 0xFF;
991 				rose_transmit_link(skb, rose_route->neigh1);
992 				if (frametype == ROSE_CLEAR_CONFIRMATION)
993 					rose_remove_route(rose_route);
994 				res = 1;
995 				goto out;
996 			} else {
997 				if (frametype == ROSE_CLEAR_CONFIRMATION)
998 					rose_remove_route(rose_route);
999 				goto out;
1000 			}
1001 		}
1002 		rose_route = rose_route->next;
1003 	}
1004 
1005 	/*
1006 	 *	We know that:
1007 	 *	1. The frame isn't for us,
1008 	 *	2. It isn't "owned" by any existing route.
1009 	 */
1010 	if (frametype != ROSE_CALL_REQUEST) {	/* XXX */
1011 		res = 0;
1012 		goto out;
1013 	}
1014 
1015 	memset(&facilities, 0x00, sizeof(struct rose_facilities_struct));
1016 
1017 	if (!rose_parse_facilities(skb->data + ROSE_CALL_REQ_FACILITIES_OFF,
1018 				   skb->len - ROSE_CALL_REQ_FACILITIES_OFF,
1019 				   &facilities)) {
1020 		rose_transmit_clear_request(rose_neigh, lci, ROSE_INVALID_FACILITY, 76);
1021 		goto out;
1022 	}
1023 
1024 	/*
1025 	 *	Check for routing loops.
1026 	 */
1027 	rose_route = rose_route_list;
1028 	while (rose_route != NULL) {
1029 		if (rose_route->rand == facilities.rand &&
1030 		    rosecmp(src_addr, &rose_route->src_addr) == 0 &&
1031 		    ax25cmp(&facilities.dest_call, &rose_route->src_call) == 0 &&
1032 		    ax25cmp(&facilities.source_call, &rose_route->dest_call) == 0) {
1033 			rose_transmit_clear_request(rose_neigh, lci, ROSE_NOT_OBTAINABLE, 120);
1034 			goto out;
1035 		}
1036 		rose_route = rose_route->next;
1037 	}
1038 
1039 	if ((new_neigh = rose_get_neigh(dest_addr, &cause, &diagnostic, 1)) == NULL) {
1040 		rose_transmit_clear_request(rose_neigh, lci, cause, diagnostic);
1041 		goto out;
1042 	}
1043 
1044 	if ((new_lci = rose_new_lci(new_neigh)) == 0) {
1045 		rose_transmit_clear_request(rose_neigh, lci, ROSE_NETWORK_CONGESTION, 71);
1046 		goto out;
1047 	}
1048 
1049 	if ((rose_route = kmalloc(sizeof(*rose_route), GFP_ATOMIC)) == NULL) {
1050 		rose_transmit_clear_request(rose_neigh, lci, ROSE_NETWORK_CONGESTION, 120);
1051 		goto out;
1052 	}
1053 
1054 	rose_route->lci1      = lci;
1055 	rose_route->src_addr  = *src_addr;
1056 	rose_route->dest_addr = *dest_addr;
1057 	rose_route->src_call  = facilities.dest_call;
1058 	rose_route->dest_call = facilities.source_call;
1059 	rose_route->rand      = facilities.rand;
1060 	rose_route->neigh1    = rose_neigh;
1061 	rose_route->lci2      = new_lci;
1062 	rose_route->neigh2    = new_neigh;
1063 
1064 	rose_route->neigh1->use++;
1065 	rose_route->neigh2->use++;
1066 
1067 	rose_route->next = rose_route_list;
1068 	rose_route_list  = rose_route;
1069 
1070 	skb->data[0] &= 0xF0;
1071 	skb->data[0] |= (rose_route->lci2 >> 8) & 0x0F;
1072 	skb->data[1]  = (rose_route->lci2 >> 0) & 0xFF;
1073 
1074 	rose_transmit_link(skb, rose_route->neigh2);
1075 	res = 1;
1076 
1077 out:
1078 	spin_unlock_bh(&rose_route_list_lock);
1079 	spin_unlock_bh(&rose_neigh_list_lock);
1080 
1081 	return res;
1082 }
1083 
1084 #ifdef CONFIG_PROC_FS
1085 
1086 static void *rose_node_start(struct seq_file *seq, loff_t *pos)
1087 	__acquires(rose_node_list_lock)
1088 {
1089 	struct rose_node *rose_node;
1090 	int i = 1;
1091 
1092 	spin_lock_bh(&rose_node_list_lock);
1093 	if (*pos == 0)
1094 		return SEQ_START_TOKEN;
1095 
1096 	for (rose_node = rose_node_list; rose_node && i < *pos;
1097 	     rose_node = rose_node->next, ++i);
1098 
1099 	return (i == *pos) ? rose_node : NULL;
1100 }
1101 
1102 static void *rose_node_next(struct seq_file *seq, void *v, loff_t *pos)
1103 {
1104 	++*pos;
1105 
1106 	return (v == SEQ_START_TOKEN) ? rose_node_list
1107 		: ((struct rose_node *)v)->next;
1108 }
1109 
1110 static void rose_node_stop(struct seq_file *seq, void *v)
1111 	__releases(rose_node_list_lock)
1112 {
1113 	spin_unlock_bh(&rose_node_list_lock);
1114 }
1115 
1116 static int rose_node_show(struct seq_file *seq, void *v)
1117 {
1118 	char rsbuf[11];
1119 	int i;
1120 
1121 	if (v == SEQ_START_TOKEN)
1122 		seq_puts(seq, "address    mask n neigh neigh neigh\n");
1123 	else {
1124 		const struct rose_node *rose_node = v;
1125 		/* if (rose_node->loopback) {
1126 			seq_printf(seq, "%-10s %04d 1 loopback\n",
1127 				   rose2asc(rsbuf, &rose_node->address),
1128 				   rose_node->mask);
1129 		} else { */
1130 			seq_printf(seq, "%-10s %04d %d",
1131 				   rose2asc(rsbuf, &rose_node->address),
1132 				   rose_node->mask,
1133 				   rose_node->count);
1134 
1135 			for (i = 0; i < rose_node->count; i++)
1136 				seq_printf(seq, " %05d",
1137 					rose_node->neighbour[i]->number);
1138 
1139 			seq_puts(seq, "\n");
1140 		/* } */
1141 	}
1142 	return 0;
1143 }
1144 
1145 static const struct seq_operations rose_node_seqops = {
1146 	.start = rose_node_start,
1147 	.next = rose_node_next,
1148 	.stop = rose_node_stop,
1149 	.show = rose_node_show,
1150 };
1151 
1152 static int rose_nodes_open(struct inode *inode, struct file *file)
1153 {
1154 	return seq_open(file, &rose_node_seqops);
1155 }
1156 
1157 const struct file_operations rose_nodes_fops = {
1158 	.owner = THIS_MODULE,
1159 	.open = rose_nodes_open,
1160 	.read = seq_read,
1161 	.llseek = seq_lseek,
1162 	.release = seq_release,
1163 };
1164 
1165 static void *rose_neigh_start(struct seq_file *seq, loff_t *pos)
1166 	__acquires(rose_neigh_list_lock)
1167 {
1168 	struct rose_neigh *rose_neigh;
1169 	int i = 1;
1170 
1171 	spin_lock_bh(&rose_neigh_list_lock);
1172 	if (*pos == 0)
1173 		return SEQ_START_TOKEN;
1174 
1175 	for (rose_neigh = rose_neigh_list; rose_neigh && i < *pos;
1176 	     rose_neigh = rose_neigh->next, ++i);
1177 
1178 	return (i == *pos) ? rose_neigh : NULL;
1179 }
1180 
1181 static void *rose_neigh_next(struct seq_file *seq, void *v, loff_t *pos)
1182 {
1183 	++*pos;
1184 
1185 	return (v == SEQ_START_TOKEN) ? rose_neigh_list
1186 		: ((struct rose_neigh *)v)->next;
1187 }
1188 
1189 static void rose_neigh_stop(struct seq_file *seq, void *v)
1190 	__releases(rose_neigh_list_lock)
1191 {
1192 	spin_unlock_bh(&rose_neigh_list_lock);
1193 }
1194 
1195 static int rose_neigh_show(struct seq_file *seq, void *v)
1196 {
1197 	char buf[11];
1198 	int i;
1199 
1200 	if (v == SEQ_START_TOKEN)
1201 		seq_puts(seq,
1202 			 "addr  callsign  dev  count use mode restart  t0  tf digipeaters\n");
1203 	else {
1204 		struct rose_neigh *rose_neigh = v;
1205 
1206 		/* if (!rose_neigh->loopback) { */
1207 		seq_printf(seq, "%05d %-9s %-4s   %3d %3d  %3s     %3s %3lu %3lu",
1208 			   rose_neigh->number,
1209 			   (rose_neigh->loopback) ? "RSLOOP-0" : ax2asc(buf, &rose_neigh->callsign),
1210 			   rose_neigh->dev ? rose_neigh->dev->name : "???",
1211 			   rose_neigh->count,
1212 			   rose_neigh->use,
1213 			   (rose_neigh->dce_mode) ? "DCE" : "DTE",
1214 			   (rose_neigh->restarted) ? "yes" : "no",
1215 			   ax25_display_timer(&rose_neigh->t0timer) / HZ,
1216 			   ax25_display_timer(&rose_neigh->ftimer)  / HZ);
1217 
1218 		if (rose_neigh->digipeat != NULL) {
1219 			for (i = 0; i < rose_neigh->digipeat->ndigi; i++)
1220 				seq_printf(seq, " %s", ax2asc(buf, &rose_neigh->digipeat->calls[i]));
1221 		}
1222 
1223 		seq_puts(seq, "\n");
1224 	}
1225 	return 0;
1226 }
1227 
1228 
1229 static const struct seq_operations rose_neigh_seqops = {
1230 	.start = rose_neigh_start,
1231 	.next = rose_neigh_next,
1232 	.stop = rose_neigh_stop,
1233 	.show = rose_neigh_show,
1234 };
1235 
1236 static int rose_neigh_open(struct inode *inode, struct file *file)
1237 {
1238 	return seq_open(file, &rose_neigh_seqops);
1239 }
1240 
1241 const struct file_operations rose_neigh_fops = {
1242 	.owner = THIS_MODULE,
1243 	.open = rose_neigh_open,
1244 	.read = seq_read,
1245 	.llseek = seq_lseek,
1246 	.release = seq_release,
1247 };
1248 
1249 
1250 static void *rose_route_start(struct seq_file *seq, loff_t *pos)
1251 	__acquires(rose_route_list_lock)
1252 {
1253 	struct rose_route *rose_route;
1254 	int i = 1;
1255 
1256 	spin_lock_bh(&rose_route_list_lock);
1257 	if (*pos == 0)
1258 		return SEQ_START_TOKEN;
1259 
1260 	for (rose_route = rose_route_list; rose_route && i < *pos;
1261 	     rose_route = rose_route->next, ++i);
1262 
1263 	return (i == *pos) ? rose_route : NULL;
1264 }
1265 
1266 static void *rose_route_next(struct seq_file *seq, void *v, loff_t *pos)
1267 {
1268 	++*pos;
1269 
1270 	return (v == SEQ_START_TOKEN) ? rose_route_list
1271 		: ((struct rose_route *)v)->next;
1272 }
1273 
1274 static void rose_route_stop(struct seq_file *seq, void *v)
1275 	__releases(rose_route_list_lock)
1276 {
1277 	spin_unlock_bh(&rose_route_list_lock);
1278 }
1279 
1280 static int rose_route_show(struct seq_file *seq, void *v)
1281 {
1282 	char buf[11], rsbuf[11];
1283 
1284 	if (v == SEQ_START_TOKEN)
1285 		seq_puts(seq,
1286 			 "lci  address     callsign   neigh  <-> lci  address     callsign   neigh\n");
1287 	else {
1288 		struct rose_route *rose_route = v;
1289 
1290 		if (rose_route->neigh1)
1291 			seq_printf(seq,
1292 				   "%3.3X  %-10s  %-9s  %05d      ",
1293 				   rose_route->lci1,
1294 				   rose2asc(rsbuf, &rose_route->src_addr),
1295 				   ax2asc(buf, &rose_route->src_call),
1296 				   rose_route->neigh1->number);
1297 		else
1298 			seq_puts(seq,
1299 				 "000  *           *          00000      ");
1300 
1301 		if (rose_route->neigh2)
1302 			seq_printf(seq,
1303 				   "%3.3X  %-10s  %-9s  %05d\n",
1304 				   rose_route->lci2,
1305 				   rose2asc(rsbuf, &rose_route->dest_addr),
1306 				   ax2asc(buf, &rose_route->dest_call),
1307 				   rose_route->neigh2->number);
1308 		 else
1309 			 seq_puts(seq,
1310 				  "000  *           *          00000\n");
1311 		}
1312 	return 0;
1313 }
1314 
1315 static const struct seq_operations rose_route_seqops = {
1316 	.start = rose_route_start,
1317 	.next = rose_route_next,
1318 	.stop = rose_route_stop,
1319 	.show = rose_route_show,
1320 };
1321 
1322 static int rose_route_open(struct inode *inode, struct file *file)
1323 {
1324 	return seq_open(file, &rose_route_seqops);
1325 }
1326 
1327 const struct file_operations rose_routes_fops = {
1328 	.owner = THIS_MODULE,
1329 	.open = rose_route_open,
1330 	.read = seq_read,
1331 	.llseek = seq_lseek,
1332 	.release = seq_release,
1333 };
1334 
1335 #endif /* CONFIG_PROC_FS */
1336 
1337 /*
1338  *	Release all memory associated with ROSE routing structures.
1339  */
1340 void __exit rose_rt_free(void)
1341 {
1342 	struct rose_neigh *s, *rose_neigh = rose_neigh_list;
1343 	struct rose_node  *t, *rose_node  = rose_node_list;
1344 	struct rose_route *u, *rose_route = rose_route_list;
1345 
1346 	while (rose_neigh != NULL) {
1347 		s          = rose_neigh;
1348 		rose_neigh = rose_neigh->next;
1349 
1350 		rose_remove_neigh(s);
1351 	}
1352 
1353 	while (rose_node != NULL) {
1354 		t         = rose_node;
1355 		rose_node = rose_node->next;
1356 
1357 		rose_remove_node(t);
1358 	}
1359 
1360 	while (rose_route != NULL) {
1361 		u          = rose_route;
1362 		rose_route = rose_route->next;
1363 
1364 		rose_remove_route(u);
1365 	}
1366 }
1367