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
36static unsigned int rose_neigh_no = 1;
37
38static struct rose_node  *rose_node_list;
39static DEFINE_SPINLOCK(rose_node_list_lock);
40static struct rose_neigh *rose_neigh_list;
41static DEFINE_SPINLOCK(rose_neigh_list_lock);
42static struct rose_route *rose_route_list;
43static DEFINE_SPINLOCK(rose_route_list_lock);
44
45struct 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 */
51static 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
192out:
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 */
202static 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 */
226static void rose_remove_neigh(struct rose_neigh *rose_neigh)
227{
228	struct rose_neigh *s;
229
230	del_timer_sync(&rose_neigh->ftimer);
231	del_timer_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 */
261static 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 */
292static 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
360out:
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 */
370void 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 */
404int 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
440out:
441	spin_unlock_bh(&rose_node_list_lock);
442
443	return err;
444}
445
446/*
447 *	Delete a loopback node.
448 */
449void 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
471out:
472	spin_unlock_bh(&rose_node_list_lock);
473}
474
475/*
476 *	A device has been removed. Remove its routes and neighbours.
477 */
478void rose_rt_device_down(struct net_device *dev)
479{
480	struct rose_neigh *s, *rose_neigh;
481	struct rose_node  *t, *rose_node;
482	int i;
483
484	spin_lock_bh(&rose_node_list_lock);
485	spin_lock_bh(&rose_neigh_list_lock);
486	rose_neigh = rose_neigh_list;
487	while (rose_neigh != NULL) {
488		s          = rose_neigh;
489		rose_neigh = rose_neigh->next;
490
491		if (s->dev != dev)
492			continue;
493
494		rose_node = rose_node_list;
495
496		while (rose_node != NULL) {
497			t         = rose_node;
498			rose_node = rose_node->next;
499
500			for (i = 0; i < t->count; i++) {
501				if (t->neighbour[i] != s)
502					continue;
503
504				t->count--;
505
506				switch (i) {
507				case 0:
508					t->neighbour[0] = t->neighbour[1];
509					fallthrough;
510				case 1:
511					t->neighbour[1] = t->neighbour[2];
512					break;
513				case 2:
514					break;
515				}
516			}
517
518			if (t->count <= 0)
519				rose_remove_node(t);
520		}
521
522		rose_remove_neigh(s);
523	}
524	spin_unlock_bh(&rose_neigh_list_lock);
525	spin_unlock_bh(&rose_node_list_lock);
526}
527
528#if 0 /* Currently unused */
529/*
530 *	A device has been removed. Remove its links.
531 */
532void 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 */
554static 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 */
592static 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 */
608struct 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	if (first)
619		dev_hold(first);
620	rcu_read_unlock();
621
622	return first;
623}
624
625/*
626 *	Find the ROSE device for the given address.
627 */
628struct net_device *rose_dev_get(rose_address *addr)
629{
630	struct net_device *dev;
631
632	rcu_read_lock();
633	for_each_netdev_rcu(&init_net, dev) {
634		if ((dev->flags & IFF_UP) && dev->type == ARPHRD_ROSE &&
635		    rosecmp(addr, (const rose_address *)dev->dev_addr) == 0) {
636			dev_hold(dev);
637			goto out;
638		}
639	}
640	dev = NULL;
641out:
642	rcu_read_unlock();
643	return dev;
644}
645
646static int rose_dev_exists(rose_address *addr)
647{
648	struct net_device *dev;
649
650	rcu_read_lock();
651	for_each_netdev_rcu(&init_net, dev) {
652		if ((dev->flags & IFF_UP) && dev->type == ARPHRD_ROSE &&
653		    rosecmp(addr, (const rose_address *)dev->dev_addr) == 0)
654			goto out;
655	}
656	dev = NULL;
657out:
658	rcu_read_unlock();
659	return dev != NULL;
660}
661
662
663
664
665struct rose_route *rose_route_free_lci(unsigned int lci, struct rose_neigh *neigh)
666{
667	struct rose_route *rose_route;
668
669	for (rose_route = rose_route_list; rose_route != NULL; rose_route = rose_route->next)
670		if ((rose_route->neigh1 == neigh && rose_route->lci1 == lci) ||
671		    (rose_route->neigh2 == neigh && rose_route->lci2 == lci))
672			return rose_route;
673
674	return NULL;
675}
676
677/*
678 *	Find a neighbour or a route given a ROSE address.
679 */
680struct rose_neigh *rose_get_neigh(rose_address *addr, unsigned char *cause,
681	unsigned char *diagnostic, int route_frame)
682{
683	struct rose_neigh *res = NULL;
684	struct rose_node *node;
685	int failed = 0;
686	int i;
687
688	if (!route_frame) spin_lock_bh(&rose_node_list_lock);
689	for (node = rose_node_list; node != NULL; node = node->next) {
690		if (rosecmpm(addr, &node->address, node->mask) == 0) {
691			for (i = 0; i < node->count; i++) {
692				if (node->neighbour[i]->restarted) {
693					res = node->neighbour[i];
694					goto out;
695				}
696			}
697		}
698	}
699	if (!route_frame) { /* connect request */
700		for (node = rose_node_list; node != NULL; node = node->next) {
701			if (rosecmpm(addr, &node->address, node->mask) == 0) {
702				for (i = 0; i < node->count; i++) {
703					if (!rose_ftimer_running(node->neighbour[i])) {
704						res = node->neighbour[i];
705						goto out;
706					}
707					failed = 1;
708				}
709			}
710		}
711	}
712
713	if (failed) {
714		*cause      = ROSE_OUT_OF_ORDER;
715		*diagnostic = 0;
716	} else {
717		*cause      = ROSE_NOT_OBTAINABLE;
718		*diagnostic = 0;
719	}
720
721out:
722	if (!route_frame) spin_unlock_bh(&rose_node_list_lock);
723	return res;
724}
725
726/*
727 *	Handle the ioctls that control the routing functions.
728 */
729int rose_rt_ioctl(unsigned int cmd, void __user *arg)
730{
731	struct rose_route_struct rose_route;
732	struct net_device *dev;
733	int err;
734
735	switch (cmd) {
736	case SIOCADDRT:
737		if (copy_from_user(&rose_route, arg, sizeof(struct rose_route_struct)))
738			return -EFAULT;
739		if ((dev = rose_ax25_dev_find(rose_route.device)) == NULL)
740			return -EINVAL;
741		if (rose_dev_exists(&rose_route.address)) /* Can't add routes to ourself */
742			return -EINVAL;
743		if (rose_route.mask > 10) /* Mask can't be more than 10 digits */
744			return -EINVAL;
745		if (rose_route.ndigis > AX25_MAX_DIGIS)
746			return -EINVAL;
747		err = rose_add_node(&rose_route, dev);
748		return err;
749
750	case SIOCDELRT:
751		if (copy_from_user(&rose_route, arg, sizeof(struct rose_route_struct)))
752			return -EFAULT;
753		if ((dev = rose_ax25_dev_find(rose_route.device)) == NULL)
754			return -EINVAL;
755		err = rose_del_node(&rose_route, dev);
756		return err;
757
758	case SIOCRSCLRRT:
759		return rose_clear_routes();
760
761	default:
762		return -EINVAL;
763	}
764
765	return 0;
766}
767
768static void rose_del_route_by_neigh(struct rose_neigh *rose_neigh)
769{
770	struct rose_route *rose_route, *s;
771
772	rose_neigh->restarted = 0;
773
774	rose_stop_t0timer(rose_neigh);
775	rose_start_ftimer(rose_neigh);
776
777	skb_queue_purge(&rose_neigh->queue);
778
779	spin_lock_bh(&rose_route_list_lock);
780
781	rose_route = rose_route_list;
782
783	while (rose_route != NULL) {
784		if ((rose_route->neigh1 == rose_neigh && rose_route->neigh2 == rose_neigh) ||
785		    (rose_route->neigh1 == rose_neigh && rose_route->neigh2 == NULL)       ||
786		    (rose_route->neigh2 == rose_neigh && rose_route->neigh1 == NULL)) {
787			s = rose_route->next;
788			rose_remove_route(rose_route);
789			rose_route = s;
790			continue;
791		}
792
793		if (rose_route->neigh1 == rose_neigh) {
794			rose_route->neigh1->use--;
795			rose_route->neigh1 = NULL;
796			rose_transmit_clear_request(rose_route->neigh2, rose_route->lci2, ROSE_OUT_OF_ORDER, 0);
797		}
798
799		if (rose_route->neigh2 == rose_neigh) {
800			rose_route->neigh2->use--;
801			rose_route->neigh2 = NULL;
802			rose_transmit_clear_request(rose_route->neigh1, rose_route->lci1, ROSE_OUT_OF_ORDER, 0);
803		}
804
805		rose_route = rose_route->next;
806	}
807	spin_unlock_bh(&rose_route_list_lock);
808}
809
810/*
811 * 	A level 2 link has timed out, therefore it appears to be a poor link,
812 *	then don't use that neighbour until it is reset. Blow away all through
813 *	routes and connections using this route.
814 */
815void rose_link_failed(ax25_cb *ax25, int reason)
816{
817	struct rose_neigh *rose_neigh;
818
819	spin_lock_bh(&rose_neigh_list_lock);
820	rose_neigh = rose_neigh_list;
821	while (rose_neigh != NULL) {
822		if (rose_neigh->ax25 == ax25)
823			break;
824		rose_neigh = rose_neigh->next;
825	}
826
827	if (rose_neigh != NULL) {
828		rose_neigh->ax25 = NULL;
829		ax25_cb_put(ax25);
830
831		rose_del_route_by_neigh(rose_neigh);
832		rose_kill_by_neigh(rose_neigh);
833	}
834	spin_unlock_bh(&rose_neigh_list_lock);
835}
836
837/*
838 * 	A device has been "downed" remove its link status. Blow away all
839 *	through routes and connections that use this device.
840 */
841void rose_link_device_down(struct net_device *dev)
842{
843	struct rose_neigh *rose_neigh;
844
845	for (rose_neigh = rose_neigh_list; rose_neigh != NULL; rose_neigh = rose_neigh->next) {
846		if (rose_neigh->dev == dev) {
847			rose_del_route_by_neigh(rose_neigh);
848			rose_kill_by_neigh(rose_neigh);
849		}
850	}
851}
852
853/*
854 *	Route a frame to an appropriate AX.25 connection.
855 *	A NULL ax25_cb indicates an internally generated frame.
856 */
857int rose_route_frame(struct sk_buff *skb, ax25_cb *ax25)
858{
859	struct rose_neigh *rose_neigh, *new_neigh;
860	struct rose_route *rose_route;
861	struct rose_facilities_struct facilities;
862	rose_address *src_addr, *dest_addr;
863	struct sock *sk;
864	unsigned short frametype;
865	unsigned int lci, new_lci;
866	unsigned char cause, diagnostic;
867	struct net_device *dev;
868	int res = 0;
869	char buf[11];
870
871	if (skb->len < ROSE_MIN_LEN)
872		return res;
873
874	if (!ax25)
875		return rose_loopback_queue(skb, NULL);
876
877	frametype = skb->data[2];
878	lci = ((skb->data[0] << 8) & 0xF00) + ((skb->data[1] << 0) & 0x0FF);
879	if (frametype == ROSE_CALL_REQUEST &&
880	    (skb->len <= ROSE_CALL_REQ_FACILITIES_OFF ||
881	     skb->data[ROSE_CALL_REQ_ADDR_LEN_OFF] !=
882	     ROSE_CALL_REQ_ADDR_LEN_VAL))
883		return res;
884	src_addr  = (rose_address *)(skb->data + ROSE_CALL_REQ_SRC_ADDR_OFF);
885	dest_addr = (rose_address *)(skb->data + ROSE_CALL_REQ_DEST_ADDR_OFF);
886
887	spin_lock_bh(&rose_neigh_list_lock);
888	spin_lock_bh(&rose_route_list_lock);
889
890	rose_neigh = rose_neigh_list;
891	while (rose_neigh != NULL) {
892		if (ax25cmp(&ax25->dest_addr, &rose_neigh->callsign) == 0 &&
893		    ax25->ax25_dev->dev == rose_neigh->dev)
894			break;
895		rose_neigh = rose_neigh->next;
896	}
897
898	if (rose_neigh == NULL) {
899		printk("rose_route : unknown neighbour or device %s\n",
900		       ax2asc(buf, &ax25->dest_addr));
901		goto out;
902	}
903
904	/*
905	 *	Obviously the link is working, halt the ftimer.
906	 */
907	rose_stop_ftimer(rose_neigh);
908
909	/*
910	 *	LCI of zero is always for us, and its always a restart
911	 * 	frame.
912	 */
913	if (lci == 0) {
914		rose_link_rx_restart(skb, rose_neigh, frametype);
915		goto out;
916	}
917
918	/*
919	 *	Find an existing socket.
920	 */
921	if ((sk = rose_find_socket(lci, rose_neigh)) != NULL) {
922		if (frametype == ROSE_CALL_REQUEST) {
923			struct rose_sock *rose = rose_sk(sk);
924
925			/* Remove an existing unused socket */
926			rose_clear_queues(sk);
927			rose->cause	 = ROSE_NETWORK_CONGESTION;
928			rose->diagnostic = 0;
929			rose->neighbour->use--;
930			rose->neighbour	 = NULL;
931			rose->lci	 = 0;
932			rose->state	 = ROSE_STATE_0;
933			sk->sk_state	 = TCP_CLOSE;
934			sk->sk_err	 = 0;
935			sk->sk_shutdown	 |= SEND_SHUTDOWN;
936			if (!sock_flag(sk, SOCK_DEAD)) {
937				sk->sk_state_change(sk);
938				sock_set_flag(sk, SOCK_DEAD);
939			}
940		}
941		else {
942			skb_reset_transport_header(skb);
943			res = rose_process_rx_frame(sk, skb);
944			goto out;
945		}
946	}
947
948	/*
949	 *	Is is a Call Request and is it for us ?
950	 */
951	if (frametype == ROSE_CALL_REQUEST)
952		if ((dev = rose_dev_get(dest_addr)) != NULL) {
953			res = rose_rx_call_request(skb, dev, rose_neigh, lci);
954			dev_put(dev);
955			goto out;
956		}
957
958	if (!sysctl_rose_routing_control) {
959		rose_transmit_clear_request(rose_neigh, lci, ROSE_NOT_OBTAINABLE, 0);
960		goto out;
961	}
962
963	/*
964	 *	Route it to the next in line if we have an entry for it.
965	 */
966	rose_route = rose_route_list;
967	while (rose_route != NULL) {
968		if (rose_route->lci1 == lci &&
969		    rose_route->neigh1 == rose_neigh) {
970			if (frametype == ROSE_CALL_REQUEST) {
971				/* F6FBB - Remove an existing unused route */
972				rose_remove_route(rose_route);
973				break;
974			} else if (rose_route->neigh2 != NULL) {
975				skb->data[0] &= 0xF0;
976				skb->data[0] |= (rose_route->lci2 >> 8) & 0x0F;
977				skb->data[1]  = (rose_route->lci2 >> 0) & 0xFF;
978				rose_transmit_link(skb, rose_route->neigh2);
979				if (frametype == ROSE_CLEAR_CONFIRMATION)
980					rose_remove_route(rose_route);
981				res = 1;
982				goto out;
983			} else {
984				if (frametype == ROSE_CLEAR_CONFIRMATION)
985					rose_remove_route(rose_route);
986				goto out;
987			}
988		}
989		if (rose_route->lci2 == lci &&
990		    rose_route->neigh2 == rose_neigh) {
991			if (frametype == ROSE_CALL_REQUEST) {
992				/* F6FBB - Remove an existing unused route */
993				rose_remove_route(rose_route);
994				break;
995			} else if (rose_route->neigh1 != NULL) {
996				skb->data[0] &= 0xF0;
997				skb->data[0] |= (rose_route->lci1 >> 8) & 0x0F;
998				skb->data[1]  = (rose_route->lci1 >> 0) & 0xFF;
999				rose_transmit_link(skb, rose_route->neigh1);
1000				if (frametype == ROSE_CLEAR_CONFIRMATION)
1001					rose_remove_route(rose_route);
1002				res = 1;
1003				goto out;
1004			} else {
1005				if (frametype == ROSE_CLEAR_CONFIRMATION)
1006					rose_remove_route(rose_route);
1007				goto out;
1008			}
1009		}
1010		rose_route = rose_route->next;
1011	}
1012
1013	/*
1014	 *	We know that:
1015	 *	1. The frame isn't for us,
1016	 *	2. It isn't "owned" by any existing route.
1017	 */
1018	if (frametype != ROSE_CALL_REQUEST) {	/* XXX */
1019		res = 0;
1020		goto out;
1021	}
1022
1023	memset(&facilities, 0x00, sizeof(struct rose_facilities_struct));
1024
1025	if (!rose_parse_facilities(skb->data + ROSE_CALL_REQ_FACILITIES_OFF,
1026				   skb->len - ROSE_CALL_REQ_FACILITIES_OFF,
1027				   &facilities)) {
1028		rose_transmit_clear_request(rose_neigh, lci, ROSE_INVALID_FACILITY, 76);
1029		goto out;
1030	}
1031
1032	/*
1033	 *	Check for routing loops.
1034	 */
1035	rose_route = rose_route_list;
1036	while (rose_route != NULL) {
1037		if (rose_route->rand == facilities.rand &&
1038		    rosecmp(src_addr, &rose_route->src_addr) == 0 &&
1039		    ax25cmp(&facilities.dest_call, &rose_route->src_call) == 0 &&
1040		    ax25cmp(&facilities.source_call, &rose_route->dest_call) == 0) {
1041			rose_transmit_clear_request(rose_neigh, lci, ROSE_NOT_OBTAINABLE, 120);
1042			goto out;
1043		}
1044		rose_route = rose_route->next;
1045	}
1046
1047	if ((new_neigh = rose_get_neigh(dest_addr, &cause, &diagnostic, 1)) == NULL) {
1048		rose_transmit_clear_request(rose_neigh, lci, cause, diagnostic);
1049		goto out;
1050	}
1051
1052	if ((new_lci = rose_new_lci(new_neigh)) == 0) {
1053		rose_transmit_clear_request(rose_neigh, lci, ROSE_NETWORK_CONGESTION, 71);
1054		goto out;
1055	}
1056
1057	if ((rose_route = kmalloc(sizeof(*rose_route), GFP_ATOMIC)) == NULL) {
1058		rose_transmit_clear_request(rose_neigh, lci, ROSE_NETWORK_CONGESTION, 120);
1059		goto out;
1060	}
1061
1062	rose_route->lci1      = lci;
1063	rose_route->src_addr  = *src_addr;
1064	rose_route->dest_addr = *dest_addr;
1065	rose_route->src_call  = facilities.dest_call;
1066	rose_route->dest_call = facilities.source_call;
1067	rose_route->rand      = facilities.rand;
1068	rose_route->neigh1    = rose_neigh;
1069	rose_route->lci2      = new_lci;
1070	rose_route->neigh2    = new_neigh;
1071
1072	rose_route->neigh1->use++;
1073	rose_route->neigh2->use++;
1074
1075	rose_route->next = rose_route_list;
1076	rose_route_list  = rose_route;
1077
1078	skb->data[0] &= 0xF0;
1079	skb->data[0] |= (rose_route->lci2 >> 8) & 0x0F;
1080	skb->data[1]  = (rose_route->lci2 >> 0) & 0xFF;
1081
1082	rose_transmit_link(skb, rose_route->neigh2);
1083	res = 1;
1084
1085out:
1086	spin_unlock_bh(&rose_route_list_lock);
1087	spin_unlock_bh(&rose_neigh_list_lock);
1088
1089	return res;
1090}
1091
1092#ifdef CONFIG_PROC_FS
1093
1094static void *rose_node_start(struct seq_file *seq, loff_t *pos)
1095	__acquires(rose_node_list_lock)
1096{
1097	struct rose_node *rose_node;
1098	int i = 1;
1099
1100	spin_lock_bh(&rose_node_list_lock);
1101	if (*pos == 0)
1102		return SEQ_START_TOKEN;
1103
1104	for (rose_node = rose_node_list; rose_node && i < *pos;
1105	     rose_node = rose_node->next, ++i);
1106
1107	return (i == *pos) ? rose_node : NULL;
1108}
1109
1110static void *rose_node_next(struct seq_file *seq, void *v, loff_t *pos)
1111{
1112	++*pos;
1113
1114	return (v == SEQ_START_TOKEN) ? rose_node_list
1115		: ((struct rose_node *)v)->next;
1116}
1117
1118static void rose_node_stop(struct seq_file *seq, void *v)
1119	__releases(rose_node_list_lock)
1120{
1121	spin_unlock_bh(&rose_node_list_lock);
1122}
1123
1124static int rose_node_show(struct seq_file *seq, void *v)
1125{
1126	char rsbuf[11];
1127	int i;
1128
1129	if (v == SEQ_START_TOKEN)
1130		seq_puts(seq, "address    mask n neigh neigh neigh\n");
1131	else {
1132		const struct rose_node *rose_node = v;
1133		seq_printf(seq, "%-10s %04d %d",
1134			   rose2asc(rsbuf, &rose_node->address),
1135			   rose_node->mask,
1136			   rose_node->count);
1137
1138		for (i = 0; i < rose_node->count; i++)
1139			seq_printf(seq, " %05d", rose_node->neighbour[i]->number);
1140
1141		seq_puts(seq, "\n");
1142	}
1143	return 0;
1144}
1145
1146const struct seq_operations rose_node_seqops = {
1147	.start = rose_node_start,
1148	.next = rose_node_next,
1149	.stop = rose_node_stop,
1150	.show = rose_node_show,
1151};
1152
1153static void *rose_neigh_start(struct seq_file *seq, loff_t *pos)
1154	__acquires(rose_neigh_list_lock)
1155{
1156	struct rose_neigh *rose_neigh;
1157	int i = 1;
1158
1159	spin_lock_bh(&rose_neigh_list_lock);
1160	if (*pos == 0)
1161		return SEQ_START_TOKEN;
1162
1163	for (rose_neigh = rose_neigh_list; rose_neigh && i < *pos;
1164	     rose_neigh = rose_neigh->next, ++i);
1165
1166	return (i == *pos) ? rose_neigh : NULL;
1167}
1168
1169static void *rose_neigh_next(struct seq_file *seq, void *v, loff_t *pos)
1170{
1171	++*pos;
1172
1173	return (v == SEQ_START_TOKEN) ? rose_neigh_list
1174		: ((struct rose_neigh *)v)->next;
1175}
1176
1177static void rose_neigh_stop(struct seq_file *seq, void *v)
1178	__releases(rose_neigh_list_lock)
1179{
1180	spin_unlock_bh(&rose_neigh_list_lock);
1181}
1182
1183static int rose_neigh_show(struct seq_file *seq, void *v)
1184{
1185	char buf[11];
1186	int i;
1187
1188	if (v == SEQ_START_TOKEN)
1189		seq_puts(seq,
1190			 "addr  callsign  dev  count use mode restart  t0  tf digipeaters\n");
1191	else {
1192		struct rose_neigh *rose_neigh = v;
1193
1194		/* if (!rose_neigh->loopback) { */
1195		seq_printf(seq, "%05d %-9s %-4s   %3d %3d  %3s     %3s %3lu %3lu",
1196			   rose_neigh->number,
1197			   (rose_neigh->loopback) ? "RSLOOP-0" : ax2asc(buf, &rose_neigh->callsign),
1198			   rose_neigh->dev ? rose_neigh->dev->name : "???",
1199			   rose_neigh->count,
1200			   rose_neigh->use,
1201			   (rose_neigh->dce_mode) ? "DCE" : "DTE",
1202			   (rose_neigh->restarted) ? "yes" : "no",
1203			   ax25_display_timer(&rose_neigh->t0timer) / HZ,
1204			   ax25_display_timer(&rose_neigh->ftimer)  / HZ);
1205
1206		if (rose_neigh->digipeat != NULL) {
1207			for (i = 0; i < rose_neigh->digipeat->ndigi; i++)
1208				seq_printf(seq, " %s", ax2asc(buf, &rose_neigh->digipeat->calls[i]));
1209		}
1210
1211		seq_puts(seq, "\n");
1212	}
1213	return 0;
1214}
1215
1216
1217const struct seq_operations rose_neigh_seqops = {
1218	.start = rose_neigh_start,
1219	.next = rose_neigh_next,
1220	.stop = rose_neigh_stop,
1221	.show = rose_neigh_show,
1222};
1223
1224static void *rose_route_start(struct seq_file *seq, loff_t *pos)
1225	__acquires(rose_route_list_lock)
1226{
1227	struct rose_route *rose_route;
1228	int i = 1;
1229
1230	spin_lock_bh(&rose_route_list_lock);
1231	if (*pos == 0)
1232		return SEQ_START_TOKEN;
1233
1234	for (rose_route = rose_route_list; rose_route && i < *pos;
1235	     rose_route = rose_route->next, ++i);
1236
1237	return (i == *pos) ? rose_route : NULL;
1238}
1239
1240static void *rose_route_next(struct seq_file *seq, void *v, loff_t *pos)
1241{
1242	++*pos;
1243
1244	return (v == SEQ_START_TOKEN) ? rose_route_list
1245		: ((struct rose_route *)v)->next;
1246}
1247
1248static void rose_route_stop(struct seq_file *seq, void *v)
1249	__releases(rose_route_list_lock)
1250{
1251	spin_unlock_bh(&rose_route_list_lock);
1252}
1253
1254static int rose_route_show(struct seq_file *seq, void *v)
1255{
1256	char buf[11], rsbuf[11];
1257
1258	if (v == SEQ_START_TOKEN)
1259		seq_puts(seq,
1260			 "lci  address     callsign   neigh  <-> lci  address     callsign   neigh\n");
1261	else {
1262		struct rose_route *rose_route = v;
1263
1264		if (rose_route->neigh1)
1265			seq_printf(seq,
1266				   "%3.3X  %-10s  %-9s  %05d      ",
1267				   rose_route->lci1,
1268				   rose2asc(rsbuf, &rose_route->src_addr),
1269				   ax2asc(buf, &rose_route->src_call),
1270				   rose_route->neigh1->number);
1271		else
1272			seq_puts(seq,
1273				 "000  *           *          00000      ");
1274
1275		if (rose_route->neigh2)
1276			seq_printf(seq,
1277				   "%3.3X  %-10s  %-9s  %05d\n",
1278				   rose_route->lci2,
1279				   rose2asc(rsbuf, &rose_route->dest_addr),
1280				   ax2asc(buf, &rose_route->dest_call),
1281				   rose_route->neigh2->number);
1282		 else
1283			 seq_puts(seq,
1284				  "000  *           *          00000\n");
1285		}
1286	return 0;
1287}
1288
1289struct seq_operations rose_route_seqops = {
1290	.start = rose_route_start,
1291	.next = rose_route_next,
1292	.stop = rose_route_stop,
1293	.show = rose_route_show,
1294};
1295#endif /* CONFIG_PROC_FS */
1296
1297/*
1298 *	Release all memory associated with ROSE routing structures.
1299 */
1300void __exit rose_rt_free(void)
1301{
1302	struct rose_neigh *s, *rose_neigh = rose_neigh_list;
1303	struct rose_node  *t, *rose_node  = rose_node_list;
1304	struct rose_route *u, *rose_route = rose_route_list;
1305
1306	while (rose_neigh != NULL) {
1307		s          = rose_neigh;
1308		rose_neigh = rose_neigh->next;
1309
1310		rose_remove_neigh(s);
1311	}
1312
1313	while (rose_node != NULL) {
1314		t         = rose_node;
1315		rose_node = rose_node->next;
1316
1317		rose_remove_node(t);
1318	}
1319
1320	while (rose_route != NULL) {
1321		u          = rose_route;
1322		rose_route = rose_route->next;
1323
1324		rose_remove_route(u);
1325	}
1326}
1327