xref: /linux/net/rose/rose_route.c (revision 17bbde2e1716e2ee4b997d476b48ae85c5a47671)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *
4  * Copyright (C) Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
5  * Copyright (C) Terry Dawson VK2KTJ (terry@animats.net)
6  */
7 #include <linux/errno.h>
8 #include <linux/types.h>
9 #include <linux/socket.h>
10 #include <linux/in.h>
11 #include <linux/kernel.h>
12 #include <linux/timer.h>
13 #include <linux/string.h>
14 #include <linux/sockios.h>
15 #include <linux/net.h>
16 #include <linux/slab.h>
17 #include <net/ax25.h>
18 #include <linux/inet.h>
19 #include <linux/netdevice.h>
20 #include <net/arp.h>
21 #include <linux/if_arp.h>
22 #include <linux/skbuff.h>
23 #include <net/sock.h>
24 #include <net/tcp_states.h>
25 #include <linux/uaccess.h>
26 #include <linux/fcntl.h>
27 #include <linux/termios.h>	/* For TIOCINQ/OUTQ */
28 #include <linux/mm.h>
29 #include <linux/interrupt.h>
30 #include <linux/notifier.h>
31 #include <linux/init.h>
32 #include <net/rose.h>
33 #include <linux/seq_file.h>
34 #include <linux/export.h>
35 
36 static unsigned int rose_neigh_no = 1;
37 
38 static struct rose_node  *rose_node_list;
39 static DEFINE_SPINLOCK(rose_node_list_lock);
40 static struct rose_neigh *rose_neigh_list;
41 static DEFINE_SPINLOCK(rose_neigh_list_lock);
42 static struct rose_route *rose_route_list;
43 static DEFINE_SPINLOCK(rose_route_list_lock);
44 
45 struct rose_neigh *rose_loopback_neigh;
46 
47 /*
48  *	Add a new route to a node, and in the process add the node and the
49  *	neighbour if it is new.
50  */
rose_add_node(struct rose_route_struct * rose_route,struct net_device * dev)51 static int __must_check rose_add_node(struct rose_route_struct *rose_route,
52 	struct net_device *dev)
53 {
54 	struct rose_node  *rose_node, *rose_tmpn, *rose_tmpp;
55 	struct rose_neigh *rose_neigh;
56 	int i, res = 0;
57 
58 	spin_lock_bh(&rose_node_list_lock);
59 	spin_lock_bh(&rose_neigh_list_lock);
60 
61 	rose_node = rose_node_list;
62 	while (rose_node != NULL) {
63 		if ((rose_node->mask == rose_route->mask) &&
64 		    (rosecmpm(&rose_route->address, &rose_node->address,
65 			      rose_route->mask) == 0))
66 			break;
67 		rose_node = rose_node->next;
68 	}
69 
70 	if (rose_node != NULL && rose_node->loopback) {
71 		res = -EINVAL;
72 		goto out;
73 	}
74 
75 	rose_neigh = rose_neigh_list;
76 	while (rose_neigh != NULL) {
77 		if (ax25cmp(&rose_route->neighbour,
78 			    &rose_neigh->callsign) == 0 &&
79 		    rose_neigh->dev == dev)
80 			break;
81 		rose_neigh = rose_neigh->next;
82 	}
83 
84 	if (rose_neigh == NULL) {
85 		rose_neigh = kmalloc(sizeof(*rose_neigh), GFP_ATOMIC);
86 		if (rose_neigh == NULL) {
87 			res = -ENOMEM;
88 			goto out;
89 		}
90 
91 		rose_neigh->callsign  = rose_route->neighbour;
92 		rose_neigh->digipeat  = NULL;
93 		rose_neigh->ax25      = NULL;
94 		rose_neigh->dev       = dev;
95 		rose_neigh->count     = 0;
96 		rose_neigh->use       = 0;
97 		rose_neigh->dce_mode  = 0;
98 		rose_neigh->loopback  = 0;
99 		rose_neigh->number    = rose_neigh_no++;
100 		rose_neigh->restarted = 0;
101 
102 		skb_queue_head_init(&rose_neigh->queue);
103 
104 		timer_setup(&rose_neigh->ftimer, NULL, 0);
105 		timer_setup(&rose_neigh->t0timer, NULL, 0);
106 
107 		if (rose_route->ndigis != 0) {
108 			rose_neigh->digipeat =
109 				kmalloc(sizeof(ax25_digi), GFP_ATOMIC);
110 			if (rose_neigh->digipeat == NULL) {
111 				kfree(rose_neigh);
112 				res = -ENOMEM;
113 				goto out;
114 			}
115 
116 			rose_neigh->digipeat->ndigi      = rose_route->ndigis;
117 			rose_neigh->digipeat->lastrepeat = -1;
118 
119 			for (i = 0; i < rose_route->ndigis; i++) {
120 				rose_neigh->digipeat->calls[i]    =
121 					rose_route->digipeaters[i];
122 				rose_neigh->digipeat->repeated[i] = 0;
123 			}
124 		}
125 
126 		rose_neigh->next = rose_neigh_list;
127 		rose_neigh_list  = rose_neigh;
128 	}
129 
130 	/*
131 	 * This is a new node to be inserted into the list. Find where it needs
132 	 * to be inserted into the list, and insert it. We want to be sure
133 	 * to order the list in descending order of mask size to ensure that
134 	 * later when we are searching this list the first match will be the
135 	 * best match.
136 	 */
137 	if (rose_node == NULL) {
138 		rose_tmpn = rose_node_list;
139 		rose_tmpp = NULL;
140 
141 		while (rose_tmpn != NULL) {
142 			if (rose_tmpn->mask > rose_route->mask) {
143 				rose_tmpp = rose_tmpn;
144 				rose_tmpn = rose_tmpn->next;
145 			} else {
146 				break;
147 			}
148 		}
149 
150 		/* create new node */
151 		rose_node = kmalloc(sizeof(*rose_node), GFP_ATOMIC);
152 		if (rose_node == NULL) {
153 			res = -ENOMEM;
154 			goto out;
155 		}
156 
157 		rose_node->address      = rose_route->address;
158 		rose_node->mask         = rose_route->mask;
159 		rose_node->count        = 1;
160 		rose_node->loopback     = 0;
161 		rose_node->neighbour[0] = rose_neigh;
162 
163 		if (rose_tmpn == NULL) {
164 			if (rose_tmpp == NULL) {	/* Empty list */
165 				rose_node_list  = rose_node;
166 				rose_node->next = NULL;
167 			} else {
168 				rose_tmpp->next = rose_node;
169 				rose_node->next = NULL;
170 			}
171 		} else {
172 			if (rose_tmpp == NULL) {	/* 1st node */
173 				rose_node->next = rose_node_list;
174 				rose_node_list  = rose_node;
175 			} else {
176 				rose_tmpp->next = rose_node;
177 				rose_node->next = rose_tmpn;
178 			}
179 		}
180 		rose_neigh->count++;
181 
182 		goto out;
183 	}
184 
185 	/* We have space, slot it in */
186 	if (rose_node->count < 3) {
187 		rose_node->neighbour[rose_node->count] = rose_neigh;
188 		rose_node->count++;
189 		rose_neigh->count++;
190 	}
191 
192 out:
193 	spin_unlock_bh(&rose_neigh_list_lock);
194 	spin_unlock_bh(&rose_node_list_lock);
195 
196 	return res;
197 }
198 
199 /*
200  * Caller is holding rose_node_list_lock.
201  */
rose_remove_node(struct rose_node * rose_node)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  */
rose_remove_neigh(struct rose_neigh * rose_neigh)226 static void rose_remove_neigh(struct rose_neigh *rose_neigh)
227 {
228 	struct rose_neigh *s;
229 
230 	timer_delete_sync(&rose_neigh->ftimer);
231 	timer_delete_sync(&rose_neigh->t0timer);
232 
233 	skb_queue_purge(&rose_neigh->queue);
234 
235 	if ((s = rose_neigh_list) == rose_neigh) {
236 		rose_neigh_list = rose_neigh->next;
237 		if (rose_neigh->ax25)
238 			ax25_cb_put(rose_neigh->ax25);
239 		kfree(rose_neigh->digipeat);
240 		kfree(rose_neigh);
241 		return;
242 	}
243 
244 	while (s != NULL && s->next != NULL) {
245 		if (s->next == rose_neigh) {
246 			s->next = rose_neigh->next;
247 			if (rose_neigh->ax25)
248 				ax25_cb_put(rose_neigh->ax25);
249 			kfree(rose_neigh->digipeat);
250 			kfree(rose_neigh);
251 			return;
252 		}
253 
254 		s = s->next;
255 	}
256 }
257 
258 /*
259  * Caller is holding rose_route_list_lock.
260  */
rose_remove_route(struct rose_route * rose_route)261 static void rose_remove_route(struct rose_route *rose_route)
262 {
263 	struct rose_route *s;
264 
265 	if (rose_route->neigh1 != NULL)
266 		rose_route->neigh1->use--;
267 
268 	if (rose_route->neigh2 != NULL)
269 		rose_route->neigh2->use--;
270 
271 	if ((s = rose_route_list) == rose_route) {
272 		rose_route_list = rose_route->next;
273 		kfree(rose_route);
274 		return;
275 	}
276 
277 	while (s != NULL && s->next != NULL) {
278 		if (s->next == rose_route) {
279 			s->next = rose_route->next;
280 			kfree(rose_route);
281 			return;
282 		}
283 
284 		s = s->next;
285 	}
286 }
287 
288 /*
289  *	"Delete" a node. Strictly speaking remove a route to a node. The node
290  *	is only deleted if no routes are left to it.
291  */
rose_del_node(struct rose_route_struct * rose_route,struct net_device * dev)292 static int rose_del_node(struct rose_route_struct *rose_route,
293 	struct net_device *dev)
294 {
295 	struct rose_node  *rose_node;
296 	struct rose_neigh *rose_neigh;
297 	int i, err = 0;
298 
299 	spin_lock_bh(&rose_node_list_lock);
300 	spin_lock_bh(&rose_neigh_list_lock);
301 
302 	rose_node = rose_node_list;
303 	while (rose_node != NULL) {
304 		if ((rose_node->mask == rose_route->mask) &&
305 		    (rosecmpm(&rose_route->address, &rose_node->address,
306 			      rose_route->mask) == 0))
307 			break;
308 		rose_node = rose_node->next;
309 	}
310 
311 	if (rose_node == NULL || rose_node->loopback) {
312 		err = -EINVAL;
313 		goto out;
314 	}
315 
316 	rose_neigh = rose_neigh_list;
317 	while (rose_neigh != NULL) {
318 		if (ax25cmp(&rose_route->neighbour,
319 			    &rose_neigh->callsign) == 0 &&
320 		    rose_neigh->dev == dev)
321 			break;
322 		rose_neigh = rose_neigh->next;
323 	}
324 
325 	if (rose_neigh == NULL) {
326 		err = -EINVAL;
327 		goto out;
328 	}
329 
330 	for (i = 0; i < rose_node->count; i++) {
331 		if (rose_node->neighbour[i] == rose_neigh) {
332 			rose_neigh->count--;
333 
334 			if (rose_neigh->count == 0 && rose_neigh->use == 0)
335 				rose_remove_neigh(rose_neigh);
336 
337 			rose_node->count--;
338 
339 			if (rose_node->count == 0) {
340 				rose_remove_node(rose_node);
341 			} else {
342 				switch (i) {
343 				case 0:
344 					rose_node->neighbour[0] =
345 						rose_node->neighbour[1];
346 					fallthrough;
347 				case 1:
348 					rose_node->neighbour[1] =
349 						rose_node->neighbour[2];
350 					break;
351 				case 2:
352 					break;
353 				}
354 			}
355 			goto out;
356 		}
357 	}
358 	err = -EINVAL;
359 
360 out:
361 	spin_unlock_bh(&rose_neigh_list_lock);
362 	spin_unlock_bh(&rose_node_list_lock);
363 
364 	return err;
365 }
366 
367 /*
368  *	Add the loopback neighbour.
369  */
rose_add_loopback_neigh(void)370 void rose_add_loopback_neigh(void)
371 {
372 	struct rose_neigh *sn;
373 
374 	rose_loopback_neigh = kmalloc(sizeof(struct rose_neigh), GFP_KERNEL);
375 	if (!rose_loopback_neigh)
376 		return;
377 	sn = rose_loopback_neigh;
378 
379 	sn->callsign  = null_ax25_address;
380 	sn->digipeat  = NULL;
381 	sn->ax25      = NULL;
382 	sn->dev       = NULL;
383 	sn->count     = 0;
384 	sn->use       = 0;
385 	sn->dce_mode  = 1;
386 	sn->loopback  = 1;
387 	sn->number    = rose_neigh_no++;
388 	sn->restarted = 1;
389 
390 	skb_queue_head_init(&sn->queue);
391 
392 	timer_setup(&sn->ftimer, NULL, 0);
393 	timer_setup(&sn->t0timer, NULL, 0);
394 
395 	spin_lock_bh(&rose_neigh_list_lock);
396 	sn->next = rose_neigh_list;
397 	rose_neigh_list           = sn;
398 	spin_unlock_bh(&rose_neigh_list_lock);
399 }
400 
401 /*
402  *	Add a loopback node.
403  */
rose_add_loopback_node(const rose_address * address)404 int rose_add_loopback_node(const rose_address *address)
405 {
406 	struct rose_node *rose_node;
407 	int err = 0;
408 
409 	spin_lock_bh(&rose_node_list_lock);
410 
411 	rose_node = rose_node_list;
412 	while (rose_node != NULL) {
413 		if ((rose_node->mask == 10) &&
414 		     (rosecmpm(address, &rose_node->address, 10) == 0) &&
415 		     rose_node->loopback)
416 			break;
417 		rose_node = rose_node->next;
418 	}
419 
420 	if (rose_node != NULL)
421 		goto out;
422 
423 	if ((rose_node = kmalloc(sizeof(*rose_node), GFP_ATOMIC)) == NULL) {
424 		err = -ENOMEM;
425 		goto out;
426 	}
427 
428 	rose_node->address      = *address;
429 	rose_node->mask         = 10;
430 	rose_node->count        = 1;
431 	rose_node->loopback     = 1;
432 	rose_node->neighbour[0] = rose_loopback_neigh;
433 
434 	/* Insert at the head of list. Address is always mask=10 */
435 	rose_node->next = rose_node_list;
436 	rose_node_list  = rose_node;
437 
438 	rose_loopback_neigh->count++;
439 
440 out:
441 	spin_unlock_bh(&rose_node_list_lock);
442 
443 	return err;
444 }
445 
446 /*
447  *	Delete a loopback node.
448  */
rose_del_loopback_node(const rose_address * address)449 void rose_del_loopback_node(const rose_address *address)
450 {
451 	struct rose_node *rose_node;
452 
453 	spin_lock_bh(&rose_node_list_lock);
454 
455 	rose_node = rose_node_list;
456 	while (rose_node != NULL) {
457 		if ((rose_node->mask == 10) &&
458 		    (rosecmpm(address, &rose_node->address, 10) == 0) &&
459 		    rose_node->loopback)
460 			break;
461 		rose_node = rose_node->next;
462 	}
463 
464 	if (rose_node == NULL)
465 		goto out;
466 
467 	rose_remove_node(rose_node);
468 
469 	rose_loopback_neigh->count--;
470 
471 out:
472 	spin_unlock_bh(&rose_node_list_lock);
473 }
474 
475 /*
476  *	A device has been removed. Remove its routes and neighbours.
477  */
rose_rt_device_down(struct net_device * dev)478 void rose_rt_device_down(struct net_device *dev)
479 {
480 	struct rose_neigh *s, *rose_neigh;
481 	struct rose_node  *t, *rose_node;
482 	int i;
483 
484 	spin_lock_bh(&rose_node_list_lock);
485 	spin_lock_bh(&rose_neigh_list_lock);
486 	rose_neigh = rose_neigh_list;
487 	while (rose_neigh != NULL) {
488 		s          = rose_neigh;
489 		rose_neigh = rose_neigh->next;
490 
491 		if (s->dev != dev)
492 			continue;
493 
494 		rose_node = rose_node_list;
495 
496 		while (rose_node != NULL) {
497 			t         = rose_node;
498 			rose_node = rose_node->next;
499 
500 			for (i = t->count - 1; i >= 0; i--) {
501 				if (t->neighbour[i] != s)
502 					continue;
503 
504 				t->count--;
505 
506 				memmove(&t->neighbour[i], &t->neighbour[i + 1],
507 					sizeof(t->neighbour[0]) *
508 						(t->count - i));
509 			}
510 
511 			if (t->count <= 0)
512 				rose_remove_node(t);
513 		}
514 
515 		rose_remove_neigh(s);
516 	}
517 	spin_unlock_bh(&rose_neigh_list_lock);
518 	spin_unlock_bh(&rose_node_list_lock);
519 }
520 
521 #if 0 /* Currently unused */
522 /*
523  *	A device has been removed. Remove its links.
524  */
525 void rose_route_device_down(struct net_device *dev)
526 {
527 	struct rose_route *s, *rose_route;
528 
529 	spin_lock_bh(&rose_route_list_lock);
530 	rose_route = rose_route_list;
531 	while (rose_route != NULL) {
532 		s          = rose_route;
533 		rose_route = rose_route->next;
534 
535 		if (s->neigh1->dev == dev || s->neigh2->dev == dev)
536 			rose_remove_route(s);
537 	}
538 	spin_unlock_bh(&rose_route_list_lock);
539 }
540 #endif
541 
542 /*
543  *	Clear all nodes and neighbours out, except for neighbours with
544  *	active connections going through them.
545  *  Do not clear loopback neighbour and nodes.
546  */
rose_clear_routes(void)547 static int rose_clear_routes(void)
548 {
549 	struct rose_neigh *s, *rose_neigh;
550 	struct rose_node  *t, *rose_node;
551 
552 	spin_lock_bh(&rose_node_list_lock);
553 	spin_lock_bh(&rose_neigh_list_lock);
554 
555 	rose_neigh = rose_neigh_list;
556 	rose_node  = rose_node_list;
557 
558 	while (rose_node != NULL) {
559 		t         = rose_node;
560 		rose_node = rose_node->next;
561 		if (!t->loopback)
562 			rose_remove_node(t);
563 	}
564 
565 	while (rose_neigh != NULL) {
566 		s          = rose_neigh;
567 		rose_neigh = rose_neigh->next;
568 
569 		if (s->use == 0 && !s->loopback) {
570 			s->count = 0;
571 			rose_remove_neigh(s);
572 		}
573 	}
574 
575 	spin_unlock_bh(&rose_neigh_list_lock);
576 	spin_unlock_bh(&rose_node_list_lock);
577 
578 	return 0;
579 }
580 
581 /*
582  *	Check that the device given is a valid AX.25 interface that is "up".
583  * 	called with RTNL
584  */
rose_ax25_dev_find(char * devname)585 static struct net_device *rose_ax25_dev_find(char *devname)
586 {
587 	struct net_device *dev;
588 
589 	if ((dev = __dev_get_by_name(&init_net, devname)) == NULL)
590 		return NULL;
591 
592 	if ((dev->flags & IFF_UP) && dev->type == ARPHRD_AX25)
593 		return dev;
594 
595 	return NULL;
596 }
597 
598 /*
599  *	Find the first active ROSE device, usually "rose0".
600  */
rose_dev_first(void)601 struct net_device *rose_dev_first(void)
602 {
603 	struct net_device *dev, *first = NULL;
604 
605 	rcu_read_lock();
606 	for_each_netdev_rcu(&init_net, dev) {
607 		if ((dev->flags & IFF_UP) && dev->type == ARPHRD_ROSE)
608 			if (first == NULL || strncmp(dev->name, first->name, 3) < 0)
609 				first = dev;
610 	}
611 	if (first)
612 		dev_hold(first);
613 	rcu_read_unlock();
614 
615 	return first;
616 }
617 
618 /*
619  *	Find the ROSE device for the given address.
620  */
rose_dev_get(rose_address * addr)621 struct net_device *rose_dev_get(rose_address *addr)
622 {
623 	struct net_device *dev;
624 
625 	rcu_read_lock();
626 	for_each_netdev_rcu(&init_net, dev) {
627 		if ((dev->flags & IFF_UP) && dev->type == ARPHRD_ROSE &&
628 		    rosecmp(addr, (const rose_address *)dev->dev_addr) == 0) {
629 			dev_hold(dev);
630 			goto out;
631 		}
632 	}
633 	dev = NULL;
634 out:
635 	rcu_read_unlock();
636 	return dev;
637 }
638 
rose_dev_exists(rose_address * addr)639 static int rose_dev_exists(rose_address *addr)
640 {
641 	struct net_device *dev;
642 
643 	rcu_read_lock();
644 	for_each_netdev_rcu(&init_net, dev) {
645 		if ((dev->flags & IFF_UP) && dev->type == ARPHRD_ROSE &&
646 		    rosecmp(addr, (const rose_address *)dev->dev_addr) == 0)
647 			goto out;
648 	}
649 	dev = NULL;
650 out:
651 	rcu_read_unlock();
652 	return dev != NULL;
653 }
654 
655 
656 
657 
rose_route_free_lci(unsigned int lci,struct rose_neigh * neigh)658 struct rose_route *rose_route_free_lci(unsigned int lci, struct rose_neigh *neigh)
659 {
660 	struct rose_route *rose_route;
661 
662 	for (rose_route = rose_route_list; rose_route != NULL; rose_route = rose_route->next)
663 		if ((rose_route->neigh1 == neigh && rose_route->lci1 == lci) ||
664 		    (rose_route->neigh2 == neigh && rose_route->lci2 == lci))
665 			return rose_route;
666 
667 	return NULL;
668 }
669 
670 /*
671  *	Find a neighbour or a route given a ROSE address.
672  */
rose_get_neigh(rose_address * addr,unsigned char * cause,unsigned char * diagnostic,int route_frame)673 struct rose_neigh *rose_get_neigh(rose_address *addr, unsigned char *cause,
674 	unsigned char *diagnostic, int route_frame)
675 {
676 	struct rose_neigh *res = NULL;
677 	struct rose_node *node;
678 	int failed = 0;
679 	int i;
680 
681 	if (!route_frame) spin_lock_bh(&rose_node_list_lock);
682 	for (node = rose_node_list; node != NULL; node = node->next) {
683 		if (rosecmpm(addr, &node->address, node->mask) == 0) {
684 			for (i = 0; i < node->count; i++) {
685 				if (node->neighbour[i]->restarted) {
686 					res = node->neighbour[i];
687 					goto out;
688 				}
689 			}
690 		}
691 	}
692 	if (!route_frame) { /* connect request */
693 		for (node = rose_node_list; node != NULL; node = node->next) {
694 			if (rosecmpm(addr, &node->address, node->mask) == 0) {
695 				for (i = 0; i < node->count; i++) {
696 					if (!rose_ftimer_running(node->neighbour[i])) {
697 						res = node->neighbour[i];
698 						goto out;
699 					}
700 					failed = 1;
701 				}
702 			}
703 		}
704 	}
705 
706 	if (failed) {
707 		*cause      = ROSE_OUT_OF_ORDER;
708 		*diagnostic = 0;
709 	} else {
710 		*cause      = ROSE_NOT_OBTAINABLE;
711 		*diagnostic = 0;
712 	}
713 
714 out:
715 	if (!route_frame) spin_unlock_bh(&rose_node_list_lock);
716 	return res;
717 }
718 
719 /*
720  *	Handle the ioctls that control the routing functions.
721  */
rose_rt_ioctl(unsigned int cmd,void __user * arg)722 int rose_rt_ioctl(unsigned int cmd, void __user *arg)
723 {
724 	struct rose_route_struct rose_route;
725 	struct net_device *dev;
726 	int err;
727 
728 	switch (cmd) {
729 	case SIOCADDRT:
730 		if (copy_from_user(&rose_route, arg, sizeof(struct rose_route_struct)))
731 			return -EFAULT;
732 		if ((dev = rose_ax25_dev_find(rose_route.device)) == NULL)
733 			return -EINVAL;
734 		if (rose_dev_exists(&rose_route.address)) /* Can't add routes to ourself */
735 			return -EINVAL;
736 		if (rose_route.mask > 10) /* Mask can't be more than 10 digits */
737 			return -EINVAL;
738 		if (rose_route.ndigis > AX25_MAX_DIGIS)
739 			return -EINVAL;
740 		err = rose_add_node(&rose_route, dev);
741 		return err;
742 
743 	case SIOCDELRT:
744 		if (copy_from_user(&rose_route, arg, sizeof(struct rose_route_struct)))
745 			return -EFAULT;
746 		if ((dev = rose_ax25_dev_find(rose_route.device)) == NULL)
747 			return -EINVAL;
748 		err = rose_del_node(&rose_route, dev);
749 		return err;
750 
751 	case SIOCRSCLRRT:
752 		return rose_clear_routes();
753 
754 	default:
755 		return -EINVAL;
756 	}
757 
758 	return 0;
759 }
760 
rose_del_route_by_neigh(struct rose_neigh * rose_neigh)761 static void rose_del_route_by_neigh(struct rose_neigh *rose_neigh)
762 {
763 	struct rose_route *rose_route, *s;
764 
765 	rose_neigh->restarted = 0;
766 
767 	rose_stop_t0timer(rose_neigh);
768 	rose_start_ftimer(rose_neigh);
769 
770 	skb_queue_purge(&rose_neigh->queue);
771 
772 	spin_lock_bh(&rose_route_list_lock);
773 
774 	rose_route = rose_route_list;
775 
776 	while (rose_route != NULL) {
777 		if ((rose_route->neigh1 == rose_neigh && rose_route->neigh2 == rose_neigh) ||
778 		    (rose_route->neigh1 == rose_neigh && rose_route->neigh2 == NULL)       ||
779 		    (rose_route->neigh2 == rose_neigh && rose_route->neigh1 == NULL)) {
780 			s = rose_route->next;
781 			rose_remove_route(rose_route);
782 			rose_route = s;
783 			continue;
784 		}
785 
786 		if (rose_route->neigh1 == rose_neigh) {
787 			rose_route->neigh1->use--;
788 			rose_route->neigh1 = NULL;
789 			rose_transmit_clear_request(rose_route->neigh2, rose_route->lci2, ROSE_OUT_OF_ORDER, 0);
790 		}
791 
792 		if (rose_route->neigh2 == rose_neigh) {
793 			rose_route->neigh2->use--;
794 			rose_route->neigh2 = NULL;
795 			rose_transmit_clear_request(rose_route->neigh1, rose_route->lci1, ROSE_OUT_OF_ORDER, 0);
796 		}
797 
798 		rose_route = rose_route->next;
799 	}
800 	spin_unlock_bh(&rose_route_list_lock);
801 }
802 
803 /*
804  * 	A level 2 link has timed out, therefore it appears to be a poor link,
805  *	then don't use that neighbour until it is reset. Blow away all through
806  *	routes and connections using this route.
807  */
rose_link_failed(ax25_cb * ax25,int reason)808 void rose_link_failed(ax25_cb *ax25, int reason)
809 {
810 	struct rose_neigh *rose_neigh;
811 
812 	spin_lock_bh(&rose_neigh_list_lock);
813 	rose_neigh = rose_neigh_list;
814 	while (rose_neigh != NULL) {
815 		if (rose_neigh->ax25 == ax25)
816 			break;
817 		rose_neigh = rose_neigh->next;
818 	}
819 
820 	if (rose_neigh != NULL) {
821 		rose_neigh->ax25 = NULL;
822 		ax25_cb_put(ax25);
823 
824 		rose_del_route_by_neigh(rose_neigh);
825 		rose_kill_by_neigh(rose_neigh);
826 	}
827 	spin_unlock_bh(&rose_neigh_list_lock);
828 }
829 
830 /*
831  * 	A device has been "downed" remove its link status. Blow away all
832  *	through routes and connections that use this device.
833  */
rose_link_device_down(struct net_device * dev)834 void rose_link_device_down(struct net_device *dev)
835 {
836 	struct rose_neigh *rose_neigh;
837 
838 	for (rose_neigh = rose_neigh_list; rose_neigh != NULL; rose_neigh = rose_neigh->next) {
839 		if (rose_neigh->dev == dev) {
840 			rose_del_route_by_neigh(rose_neigh);
841 			rose_kill_by_neigh(rose_neigh);
842 		}
843 	}
844 }
845 
846 /*
847  *	Route a frame to an appropriate AX.25 connection.
848  *	A NULL ax25_cb indicates an internally generated frame.
849  */
rose_route_frame(struct sk_buff * skb,ax25_cb * ax25)850 int rose_route_frame(struct sk_buff *skb, ax25_cb *ax25)
851 {
852 	struct rose_neigh *rose_neigh, *new_neigh;
853 	struct rose_route *rose_route;
854 	struct rose_facilities_struct facilities;
855 	rose_address *src_addr, *dest_addr;
856 	struct sock *sk;
857 	unsigned short frametype;
858 	unsigned int lci, new_lci;
859 	unsigned char cause, diagnostic;
860 	struct net_device *dev;
861 	int res = 0;
862 	char buf[11];
863 
864 	if (skb->len < ROSE_MIN_LEN)
865 		return res;
866 
867 	if (!ax25)
868 		return rose_loopback_queue(skb, NULL);
869 
870 	frametype = skb->data[2];
871 	lci = ((skb->data[0] << 8) & 0xF00) + ((skb->data[1] << 0) & 0x0FF);
872 	if (frametype == ROSE_CALL_REQUEST &&
873 	    (skb->len <= ROSE_CALL_REQ_FACILITIES_OFF ||
874 	     skb->data[ROSE_CALL_REQ_ADDR_LEN_OFF] !=
875 	     ROSE_CALL_REQ_ADDR_LEN_VAL))
876 		return res;
877 	src_addr  = (rose_address *)(skb->data + ROSE_CALL_REQ_SRC_ADDR_OFF);
878 	dest_addr = (rose_address *)(skb->data + ROSE_CALL_REQ_DEST_ADDR_OFF);
879 
880 	spin_lock_bh(&rose_neigh_list_lock);
881 	spin_lock_bh(&rose_route_list_lock);
882 
883 	rose_neigh = rose_neigh_list;
884 	while (rose_neigh != NULL) {
885 		if (ax25cmp(&ax25->dest_addr, &rose_neigh->callsign) == 0 &&
886 		    ax25->ax25_dev->dev == rose_neigh->dev)
887 			break;
888 		rose_neigh = rose_neigh->next;
889 	}
890 
891 	if (rose_neigh == NULL) {
892 		printk("rose_route : unknown neighbour or device %s\n",
893 		       ax2asc(buf, &ax25->dest_addr));
894 		goto out;
895 	}
896 
897 	/*
898 	 *	Obviously the link is working, halt the ftimer.
899 	 */
900 	rose_stop_ftimer(rose_neigh);
901 
902 	/*
903 	 *	LCI of zero is always for us, and its always a restart
904 	 * 	frame.
905 	 */
906 	if (lci == 0) {
907 		rose_link_rx_restart(skb, rose_neigh, frametype);
908 		goto out;
909 	}
910 
911 	/*
912 	 *	Find an existing socket.
913 	 */
914 	if ((sk = rose_find_socket(lci, rose_neigh)) != NULL) {
915 		if (frametype == ROSE_CALL_REQUEST) {
916 			struct rose_sock *rose = rose_sk(sk);
917 
918 			/* Remove an existing unused socket */
919 			rose_clear_queues(sk);
920 			rose->cause	 = ROSE_NETWORK_CONGESTION;
921 			rose->diagnostic = 0;
922 			rose->neighbour->use--;
923 			rose->neighbour	 = NULL;
924 			rose->lci	 = 0;
925 			rose->state	 = ROSE_STATE_0;
926 			sk->sk_state	 = TCP_CLOSE;
927 			sk->sk_err	 = 0;
928 			sk->sk_shutdown	 |= SEND_SHUTDOWN;
929 			if (!sock_flag(sk, SOCK_DEAD)) {
930 				sk->sk_state_change(sk);
931 				sock_set_flag(sk, SOCK_DEAD);
932 			}
933 		}
934 		else {
935 			skb_reset_transport_header(skb);
936 			res = rose_process_rx_frame(sk, skb);
937 			goto out;
938 		}
939 	}
940 
941 	/*
942 	 *	Is is a Call Request and is it for us ?
943 	 */
944 	if (frametype == ROSE_CALL_REQUEST)
945 		if ((dev = rose_dev_get(dest_addr)) != NULL) {
946 			res = rose_rx_call_request(skb, dev, rose_neigh, lci);
947 			dev_put(dev);
948 			goto out;
949 		}
950 
951 	if (!sysctl_rose_routing_control) {
952 		rose_transmit_clear_request(rose_neigh, lci, ROSE_NOT_OBTAINABLE, 0);
953 		goto out;
954 	}
955 
956 	/*
957 	 *	Route it to the next in line if we have an entry for it.
958 	 */
959 	rose_route = rose_route_list;
960 	while (rose_route != NULL) {
961 		if (rose_route->lci1 == lci &&
962 		    rose_route->neigh1 == rose_neigh) {
963 			if (frametype == ROSE_CALL_REQUEST) {
964 				/* F6FBB - Remove an existing unused route */
965 				rose_remove_route(rose_route);
966 				break;
967 			} else if (rose_route->neigh2 != NULL) {
968 				skb->data[0] &= 0xF0;
969 				skb->data[0] |= (rose_route->lci2 >> 8) & 0x0F;
970 				skb->data[1]  = (rose_route->lci2 >> 0) & 0xFF;
971 				rose_transmit_link(skb, rose_route->neigh2);
972 				if (frametype == ROSE_CLEAR_CONFIRMATION)
973 					rose_remove_route(rose_route);
974 				res = 1;
975 				goto out;
976 			} else {
977 				if (frametype == ROSE_CLEAR_CONFIRMATION)
978 					rose_remove_route(rose_route);
979 				goto out;
980 			}
981 		}
982 		if (rose_route->lci2 == lci &&
983 		    rose_route->neigh2 == rose_neigh) {
984 			if (frametype == ROSE_CALL_REQUEST) {
985 				/* F6FBB - Remove an existing unused route */
986 				rose_remove_route(rose_route);
987 				break;
988 			} else if (rose_route->neigh1 != NULL) {
989 				skb->data[0] &= 0xF0;
990 				skb->data[0] |= (rose_route->lci1 >> 8) & 0x0F;
991 				skb->data[1]  = (rose_route->lci1 >> 0) & 0xFF;
992 				rose_transmit_link(skb, rose_route->neigh1);
993 				if (frametype == ROSE_CLEAR_CONFIRMATION)
994 					rose_remove_route(rose_route);
995 				res = 1;
996 				goto out;
997 			} else {
998 				if (frametype == ROSE_CLEAR_CONFIRMATION)
999 					rose_remove_route(rose_route);
1000 				goto out;
1001 			}
1002 		}
1003 		rose_route = rose_route->next;
1004 	}
1005 
1006 	/*
1007 	 *	We know that:
1008 	 *	1. The frame isn't for us,
1009 	 *	2. It isn't "owned" by any existing route.
1010 	 */
1011 	if (frametype != ROSE_CALL_REQUEST) {	/* XXX */
1012 		res = 0;
1013 		goto out;
1014 	}
1015 
1016 	memset(&facilities, 0x00, sizeof(struct rose_facilities_struct));
1017 
1018 	if (!rose_parse_facilities(skb->data + ROSE_CALL_REQ_FACILITIES_OFF,
1019 				   skb->len - ROSE_CALL_REQ_FACILITIES_OFF,
1020 				   &facilities)) {
1021 		rose_transmit_clear_request(rose_neigh, lci, ROSE_INVALID_FACILITY, 76);
1022 		goto out;
1023 	}
1024 
1025 	/*
1026 	 *	Check for routing loops.
1027 	 */
1028 	rose_route = rose_route_list;
1029 	while (rose_route != NULL) {
1030 		if (rose_route->rand == facilities.rand &&
1031 		    rosecmp(src_addr, &rose_route->src_addr) == 0 &&
1032 		    ax25cmp(&facilities.dest_call, &rose_route->src_call) == 0 &&
1033 		    ax25cmp(&facilities.source_call, &rose_route->dest_call) == 0) {
1034 			rose_transmit_clear_request(rose_neigh, lci, ROSE_NOT_OBTAINABLE, 120);
1035 			goto out;
1036 		}
1037 		rose_route = rose_route->next;
1038 	}
1039 
1040 	if ((new_neigh = rose_get_neigh(dest_addr, &cause, &diagnostic, 1)) == NULL) {
1041 		rose_transmit_clear_request(rose_neigh, lci, cause, diagnostic);
1042 		goto out;
1043 	}
1044 
1045 	if ((new_lci = rose_new_lci(new_neigh)) == 0) {
1046 		rose_transmit_clear_request(rose_neigh, lci, ROSE_NETWORK_CONGESTION, 71);
1047 		goto out;
1048 	}
1049 
1050 	if ((rose_route = kmalloc(sizeof(*rose_route), GFP_ATOMIC)) == NULL) {
1051 		rose_transmit_clear_request(rose_neigh, lci, ROSE_NETWORK_CONGESTION, 120);
1052 		goto out;
1053 	}
1054 
1055 	rose_route->lci1      = lci;
1056 	rose_route->src_addr  = *src_addr;
1057 	rose_route->dest_addr = *dest_addr;
1058 	rose_route->src_call  = facilities.dest_call;
1059 	rose_route->dest_call = facilities.source_call;
1060 	rose_route->rand      = facilities.rand;
1061 	rose_route->neigh1    = rose_neigh;
1062 	rose_route->lci2      = new_lci;
1063 	rose_route->neigh2    = new_neigh;
1064 
1065 	rose_route->neigh1->use++;
1066 	rose_route->neigh2->use++;
1067 
1068 	rose_route->next = rose_route_list;
1069 	rose_route_list  = rose_route;
1070 
1071 	skb->data[0] &= 0xF0;
1072 	skb->data[0] |= (rose_route->lci2 >> 8) & 0x0F;
1073 	skb->data[1]  = (rose_route->lci2 >> 0) & 0xFF;
1074 
1075 	rose_transmit_link(skb, rose_route->neigh2);
1076 	res = 1;
1077 
1078 out:
1079 	spin_unlock_bh(&rose_route_list_lock);
1080 	spin_unlock_bh(&rose_neigh_list_lock);
1081 
1082 	return res;
1083 }
1084 
1085 #ifdef CONFIG_PROC_FS
1086 
rose_node_start(struct seq_file * seq,loff_t * pos)1087 static void *rose_node_start(struct seq_file *seq, loff_t *pos)
1088 	__acquires(rose_node_list_lock)
1089 {
1090 	struct rose_node *rose_node;
1091 	int i = 1;
1092 
1093 	spin_lock_bh(&rose_node_list_lock);
1094 	if (*pos == 0)
1095 		return SEQ_START_TOKEN;
1096 
1097 	for (rose_node = rose_node_list; rose_node && i < *pos;
1098 	     rose_node = rose_node->next, ++i);
1099 
1100 	return (i == *pos) ? rose_node : NULL;
1101 }
1102 
rose_node_next(struct seq_file * seq,void * v,loff_t * pos)1103 static void *rose_node_next(struct seq_file *seq, void *v, loff_t *pos)
1104 {
1105 	++*pos;
1106 
1107 	return (v == SEQ_START_TOKEN) ? rose_node_list
1108 		: ((struct rose_node *)v)->next;
1109 }
1110 
rose_node_stop(struct seq_file * seq,void * v)1111 static void rose_node_stop(struct seq_file *seq, void *v)
1112 	__releases(rose_node_list_lock)
1113 {
1114 	spin_unlock_bh(&rose_node_list_lock);
1115 }
1116 
rose_node_show(struct seq_file * seq,void * v)1117 static int rose_node_show(struct seq_file *seq, void *v)
1118 {
1119 	char rsbuf[11];
1120 	int i;
1121 
1122 	if (v == SEQ_START_TOKEN)
1123 		seq_puts(seq, "address    mask n neigh neigh neigh\n");
1124 	else {
1125 		const struct rose_node *rose_node = v;
1126 		seq_printf(seq, "%-10s %04d %d",
1127 			   rose2asc(rsbuf, &rose_node->address),
1128 			   rose_node->mask,
1129 			   rose_node->count);
1130 
1131 		for (i = 0; i < rose_node->count; i++)
1132 			seq_printf(seq, " %05d", rose_node->neighbour[i]->number);
1133 
1134 		seq_puts(seq, "\n");
1135 	}
1136 	return 0;
1137 }
1138 
1139 const struct seq_operations rose_node_seqops = {
1140 	.start = rose_node_start,
1141 	.next = rose_node_next,
1142 	.stop = rose_node_stop,
1143 	.show = rose_node_show,
1144 };
1145 
rose_neigh_start(struct seq_file * seq,loff_t * pos)1146 static void *rose_neigh_start(struct seq_file *seq, loff_t *pos)
1147 	__acquires(rose_neigh_list_lock)
1148 {
1149 	struct rose_neigh *rose_neigh;
1150 	int i = 1;
1151 
1152 	spin_lock_bh(&rose_neigh_list_lock);
1153 	if (*pos == 0)
1154 		return SEQ_START_TOKEN;
1155 
1156 	for (rose_neigh = rose_neigh_list; rose_neigh && i < *pos;
1157 	     rose_neigh = rose_neigh->next, ++i);
1158 
1159 	return (i == *pos) ? rose_neigh : NULL;
1160 }
1161 
rose_neigh_next(struct seq_file * seq,void * v,loff_t * pos)1162 static void *rose_neigh_next(struct seq_file *seq, void *v, loff_t *pos)
1163 {
1164 	++*pos;
1165 
1166 	return (v == SEQ_START_TOKEN) ? rose_neigh_list
1167 		: ((struct rose_neigh *)v)->next;
1168 }
1169 
rose_neigh_stop(struct seq_file * seq,void * v)1170 static void rose_neigh_stop(struct seq_file *seq, void *v)
1171 	__releases(rose_neigh_list_lock)
1172 {
1173 	spin_unlock_bh(&rose_neigh_list_lock);
1174 }
1175 
rose_neigh_show(struct seq_file * seq,void * v)1176 static int rose_neigh_show(struct seq_file *seq, void *v)
1177 {
1178 	char buf[11];
1179 	int i;
1180 
1181 	if (v == SEQ_START_TOKEN)
1182 		seq_puts(seq,
1183 			 "addr  callsign  dev  count use mode restart  t0  tf digipeaters\n");
1184 	else {
1185 		struct rose_neigh *rose_neigh = v;
1186 
1187 		/* if (!rose_neigh->loopback) { */
1188 		seq_printf(seq, "%05d %-9s %-4s   %3d %3d  %3s     %3s %3lu %3lu",
1189 			   rose_neigh->number,
1190 			   (rose_neigh->loopback) ? "RSLOOP-0" : ax2asc(buf, &rose_neigh->callsign),
1191 			   rose_neigh->dev ? rose_neigh->dev->name : "???",
1192 			   rose_neigh->count,
1193 			   rose_neigh->use,
1194 			   (rose_neigh->dce_mode) ? "DCE" : "DTE",
1195 			   (rose_neigh->restarted) ? "yes" : "no",
1196 			   ax25_display_timer(&rose_neigh->t0timer) / HZ,
1197 			   ax25_display_timer(&rose_neigh->ftimer)  / HZ);
1198 
1199 		if (rose_neigh->digipeat != NULL) {
1200 			for (i = 0; i < rose_neigh->digipeat->ndigi; i++)
1201 				seq_printf(seq, " %s", ax2asc(buf, &rose_neigh->digipeat->calls[i]));
1202 		}
1203 
1204 		seq_puts(seq, "\n");
1205 	}
1206 	return 0;
1207 }
1208 
1209 
1210 const struct seq_operations rose_neigh_seqops = {
1211 	.start = rose_neigh_start,
1212 	.next = rose_neigh_next,
1213 	.stop = rose_neigh_stop,
1214 	.show = rose_neigh_show,
1215 };
1216 
rose_route_start(struct seq_file * seq,loff_t * pos)1217 static void *rose_route_start(struct seq_file *seq, loff_t *pos)
1218 	__acquires(rose_route_list_lock)
1219 {
1220 	struct rose_route *rose_route;
1221 	int i = 1;
1222 
1223 	spin_lock_bh(&rose_route_list_lock);
1224 	if (*pos == 0)
1225 		return SEQ_START_TOKEN;
1226 
1227 	for (rose_route = rose_route_list; rose_route && i < *pos;
1228 	     rose_route = rose_route->next, ++i);
1229 
1230 	return (i == *pos) ? rose_route : NULL;
1231 }
1232 
rose_route_next(struct seq_file * seq,void * v,loff_t * pos)1233 static void *rose_route_next(struct seq_file *seq, void *v, loff_t *pos)
1234 {
1235 	++*pos;
1236 
1237 	return (v == SEQ_START_TOKEN) ? rose_route_list
1238 		: ((struct rose_route *)v)->next;
1239 }
1240 
rose_route_stop(struct seq_file * seq,void * v)1241 static void rose_route_stop(struct seq_file *seq, void *v)
1242 	__releases(rose_route_list_lock)
1243 {
1244 	spin_unlock_bh(&rose_route_list_lock);
1245 }
1246 
rose_route_show(struct seq_file * seq,void * v)1247 static int rose_route_show(struct seq_file *seq, void *v)
1248 {
1249 	char buf[11], rsbuf[11];
1250 
1251 	if (v == SEQ_START_TOKEN)
1252 		seq_puts(seq,
1253 			 "lci  address     callsign   neigh  <-> lci  address     callsign   neigh\n");
1254 	else {
1255 		struct rose_route *rose_route = v;
1256 
1257 		if (rose_route->neigh1)
1258 			seq_printf(seq,
1259 				   "%3.3X  %-10s  %-9s  %05d      ",
1260 				   rose_route->lci1,
1261 				   rose2asc(rsbuf, &rose_route->src_addr),
1262 				   ax2asc(buf, &rose_route->src_call),
1263 				   rose_route->neigh1->number);
1264 		else
1265 			seq_puts(seq,
1266 				 "000  *           *          00000      ");
1267 
1268 		if (rose_route->neigh2)
1269 			seq_printf(seq,
1270 				   "%3.3X  %-10s  %-9s  %05d\n",
1271 				   rose_route->lci2,
1272 				   rose2asc(rsbuf, &rose_route->dest_addr),
1273 				   ax2asc(buf, &rose_route->dest_call),
1274 				   rose_route->neigh2->number);
1275 		 else
1276 			 seq_puts(seq,
1277 				  "000  *           *          00000\n");
1278 		}
1279 	return 0;
1280 }
1281 
1282 struct seq_operations rose_route_seqops = {
1283 	.start = rose_route_start,
1284 	.next = rose_route_next,
1285 	.stop = rose_route_stop,
1286 	.show = rose_route_show,
1287 };
1288 #endif /* CONFIG_PROC_FS */
1289 
1290 /*
1291  *	Release all memory associated with ROSE routing structures.
1292  */
rose_rt_free(void)1293 void __exit rose_rt_free(void)
1294 {
1295 	struct rose_neigh *s, *rose_neigh = rose_neigh_list;
1296 	struct rose_node  *t, *rose_node  = rose_node_list;
1297 	struct rose_route *u, *rose_route = rose_route_list;
1298 
1299 	while (rose_neigh != NULL) {
1300 		s          = rose_neigh;
1301 		rose_neigh = rose_neigh->next;
1302 
1303 		rose_remove_neigh(s);
1304 	}
1305 
1306 	while (rose_node != NULL) {
1307 		t         = rose_node;
1308 		rose_node = rose_node->next;
1309 
1310 		rose_remove_node(t);
1311 	}
1312 
1313 	while (rose_route != NULL) {
1314 		u          = rose_route;
1315 		rose_route = rose_route->next;
1316 
1317 		rose_remove_route(u);
1318 	}
1319 }
1320