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 Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
8 * Copyright Alan Cox GW4PTS (alan@lxorguk.ukuu.org.uk)
9 * Copyright Tomi Manninen OH2BNS (oh2bns@sral.fi)
10 */
11#include <linux/errno.h>
12#include <linux/types.h>
13#include <linux/socket.h>
14#include <linux/in.h>
15#include <linux/kernel.h>
16#include <linux/timer.h>
17#include <linux/string.h>
18#include <linux/sockios.h>
19#include <linux/net.h>
20#include <linux/slab.h>
21#include <net/ax25.h>
22#include <linux/inet.h>
23#include <linux/netdevice.h>
24#include <net/arp.h>
25#include <linux/if_arp.h>
26#include <linux/skbuff.h>
27#include <net/sock.h>
28#include <linux/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 <linux/spinlock.h>
37#include <net/netrom.h>
38#include <linux/seq_file.h>
39#include <linux/export.h>
40
41static unsigned int nr_neigh_no = 1;
42
43static HLIST_HEAD(nr_node_list);
44static DEFINE_SPINLOCK(nr_node_list_lock);
45static HLIST_HEAD(nr_neigh_list);
46static DEFINE_SPINLOCK(nr_neigh_list_lock);
47
48static struct nr_node *nr_node_get(ax25_address *callsign)
49{
50	struct nr_node *found = NULL;
51	struct nr_node *nr_node;
52
53	spin_lock_bh(&nr_node_list_lock);
54	nr_node_for_each(nr_node, &nr_node_list)
55		if (ax25cmp(callsign, &nr_node->callsign) == 0) {
56			nr_node_hold(nr_node);
57			found = nr_node;
58			break;
59		}
60	spin_unlock_bh(&nr_node_list_lock);
61	return found;
62}
63
64static struct nr_neigh *nr_neigh_get_dev(ax25_address *callsign,
65					 struct net_device *dev)
66{
67	struct nr_neigh *found = NULL;
68	struct nr_neigh *nr_neigh;
69
70	spin_lock_bh(&nr_neigh_list_lock);
71	nr_neigh_for_each(nr_neigh, &nr_neigh_list)
72		if (ax25cmp(callsign, &nr_neigh->callsign) == 0 &&
73		    nr_neigh->dev == dev) {
74			nr_neigh_hold(nr_neigh);
75			found = nr_neigh;
76			break;
77		}
78	spin_unlock_bh(&nr_neigh_list_lock);
79	return found;
80}
81
82static void nr_remove_neigh(struct nr_neigh *);
83
84/*
85 *	Add a new route to a node, and in the process add the node and the
86 *	neighbour if it is new.
87 */
88static int __must_check nr_add_node(ax25_address *nr, const char *mnemonic,
89	ax25_address *ax25, ax25_digi *ax25_digi, struct net_device *dev,
90	int quality, int obs_count)
91{
92	struct nr_node  *nr_node;
93	struct nr_neigh *nr_neigh;
94	struct nr_route nr_route;
95	int i, found;
96	struct net_device *odev;
97
98	if ((odev=nr_dev_get(nr)) != NULL) {	/* Can't add routes to ourself */
99		dev_put(odev);
100		return -EINVAL;
101	}
102
103	nr_node = nr_node_get(nr);
104
105	nr_neigh = nr_neigh_get_dev(ax25, dev);
106
107	/*
108	 * The L2 link to a neighbour has failed in the past
109	 * and now a frame comes from this neighbour. We assume
110	 * it was a temporary trouble with the link and reset the
111	 * routes now (and not wait for a node broadcast).
112	 */
113	if (nr_neigh != NULL && nr_neigh->failed != 0 && quality == 0) {
114		struct nr_node *nr_nodet;
115
116		spin_lock_bh(&nr_node_list_lock);
117		nr_node_for_each(nr_nodet, &nr_node_list) {
118			nr_node_lock(nr_nodet);
119			for (i = 0; i < nr_nodet->count; i++)
120				if (nr_nodet->routes[i].neighbour == nr_neigh)
121					if (i < nr_nodet->which)
122						nr_nodet->which = i;
123			nr_node_unlock(nr_nodet);
124		}
125		spin_unlock_bh(&nr_node_list_lock);
126	}
127
128	if (nr_neigh != NULL)
129		nr_neigh->failed = 0;
130
131	if (quality == 0 && nr_neigh != NULL && nr_node != NULL) {
132		nr_neigh_put(nr_neigh);
133		nr_node_put(nr_node);
134		return 0;
135	}
136
137	if (nr_neigh == NULL) {
138		if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL) {
139			if (nr_node)
140				nr_node_put(nr_node);
141			return -ENOMEM;
142		}
143
144		nr_neigh->callsign = *ax25;
145		nr_neigh->digipeat = NULL;
146		nr_neigh->ax25     = NULL;
147		nr_neigh->dev      = dev;
148		nr_neigh->quality  = sysctl_netrom_default_path_quality;
149		nr_neigh->locked   = 0;
150		nr_neigh->count    = 0;
151		nr_neigh->number   = nr_neigh_no++;
152		nr_neigh->failed   = 0;
153		atomic_set(&nr_neigh->refcount, 1);
154
155		if (ax25_digi != NULL && ax25_digi->ndigi > 0) {
156			nr_neigh->digipeat = kmemdup(ax25_digi,
157						     sizeof(*ax25_digi),
158						     GFP_KERNEL);
159			if (nr_neigh->digipeat == NULL) {
160				kfree(nr_neigh);
161				if (nr_node)
162					nr_node_put(nr_node);
163				return -ENOMEM;
164			}
165		}
166
167		spin_lock_bh(&nr_neigh_list_lock);
168		hlist_add_head(&nr_neigh->neigh_node, &nr_neigh_list);
169		nr_neigh_hold(nr_neigh);
170		spin_unlock_bh(&nr_neigh_list_lock);
171	}
172
173	if (quality != 0 && ax25cmp(nr, ax25) == 0 && !nr_neigh->locked)
174		nr_neigh->quality = quality;
175
176	if (nr_node == NULL) {
177		if ((nr_node = kmalloc(sizeof(*nr_node), GFP_ATOMIC)) == NULL) {
178			if (nr_neigh)
179				nr_neigh_put(nr_neigh);
180			return -ENOMEM;
181		}
182
183		nr_node->callsign = *nr;
184		strcpy(nr_node->mnemonic, mnemonic);
185
186		nr_node->which = 0;
187		nr_node->count = 1;
188		atomic_set(&nr_node->refcount, 1);
189		spin_lock_init(&nr_node->node_lock);
190
191		nr_node->routes[0].quality   = quality;
192		nr_node->routes[0].obs_count = obs_count;
193		nr_node->routes[0].neighbour = nr_neigh;
194
195		nr_neigh_hold(nr_neigh);
196		nr_neigh->count++;
197
198		spin_lock_bh(&nr_node_list_lock);
199		hlist_add_head(&nr_node->node_node, &nr_node_list);
200		/* refcount initialized at 1 */
201		spin_unlock_bh(&nr_node_list_lock);
202
203		return 0;
204	}
205	nr_node_lock(nr_node);
206
207	if (quality != 0)
208		strcpy(nr_node->mnemonic, mnemonic);
209
210	for (found = 0, i = 0; i < nr_node->count; i++) {
211		if (nr_node->routes[i].neighbour == nr_neigh) {
212			nr_node->routes[i].quality   = quality;
213			nr_node->routes[i].obs_count = obs_count;
214			found = 1;
215			break;
216		}
217	}
218
219	if (!found) {
220		/* We have space at the bottom, slot it in */
221		if (nr_node->count < 3) {
222			nr_node->routes[2] = nr_node->routes[1];
223			nr_node->routes[1] = nr_node->routes[0];
224
225			nr_node->routes[0].quality   = quality;
226			nr_node->routes[0].obs_count = obs_count;
227			nr_node->routes[0].neighbour = nr_neigh;
228
229			nr_node->which++;
230			nr_node->count++;
231			nr_neigh_hold(nr_neigh);
232			nr_neigh->count++;
233		} else {
234			/* It must be better than the worst */
235			if (quality > nr_node->routes[2].quality) {
236				nr_node->routes[2].neighbour->count--;
237				nr_neigh_put(nr_node->routes[2].neighbour);
238
239				if (nr_node->routes[2].neighbour->count == 0 && !nr_node->routes[2].neighbour->locked)
240					nr_remove_neigh(nr_node->routes[2].neighbour);
241
242				nr_node->routes[2].quality   = quality;
243				nr_node->routes[2].obs_count = obs_count;
244				nr_node->routes[2].neighbour = nr_neigh;
245
246				nr_neigh_hold(nr_neigh);
247				nr_neigh->count++;
248			}
249		}
250	}
251
252	/* Now re-sort the routes in quality order */
253	switch (nr_node->count) {
254	case 3:
255		if (nr_node->routes[1].quality > nr_node->routes[0].quality) {
256			switch (nr_node->which) {
257			case 0:
258				nr_node->which = 1;
259				break;
260			case 1:
261				nr_node->which = 0;
262				break;
263			}
264			nr_route           = nr_node->routes[0];
265			nr_node->routes[0] = nr_node->routes[1];
266			nr_node->routes[1] = nr_route;
267		}
268		if (nr_node->routes[2].quality > nr_node->routes[1].quality) {
269			switch (nr_node->which) {
270			case 1:  nr_node->which = 2;
271				break;
272
273			case 2:  nr_node->which = 1;
274				break;
275
276			default:
277				break;
278			}
279			nr_route           = nr_node->routes[1];
280			nr_node->routes[1] = nr_node->routes[2];
281			nr_node->routes[2] = nr_route;
282		}
283	case 2:
284		if (nr_node->routes[1].quality > nr_node->routes[0].quality) {
285			switch (nr_node->which) {
286			case 0:  nr_node->which = 1;
287				break;
288
289			case 1:  nr_node->which = 0;
290				break;
291
292			default: break;
293			}
294			nr_route           = nr_node->routes[0];
295			nr_node->routes[0] = nr_node->routes[1];
296			nr_node->routes[1] = nr_route;
297			}
298	case 1:
299		break;
300	}
301
302	for (i = 0; i < nr_node->count; i++) {
303		if (nr_node->routes[i].neighbour == nr_neigh) {
304			if (i < nr_node->which)
305				nr_node->which = i;
306			break;
307		}
308	}
309
310	nr_neigh_put(nr_neigh);
311	nr_node_unlock(nr_node);
312	nr_node_put(nr_node);
313	return 0;
314}
315
316static inline void __nr_remove_node(struct nr_node *nr_node)
317{
318	hlist_del_init(&nr_node->node_node);
319	nr_node_put(nr_node);
320}
321
322#define nr_remove_node_locked(__node) \
323	__nr_remove_node(__node)
324
325static void nr_remove_node(struct nr_node *nr_node)
326{
327	spin_lock_bh(&nr_node_list_lock);
328	__nr_remove_node(nr_node);
329	spin_unlock_bh(&nr_node_list_lock);
330}
331
332static inline void __nr_remove_neigh(struct nr_neigh *nr_neigh)
333{
334	hlist_del_init(&nr_neigh->neigh_node);
335	nr_neigh_put(nr_neigh);
336}
337
338#define nr_remove_neigh_locked(__neigh) \
339	__nr_remove_neigh(__neigh)
340
341static void nr_remove_neigh(struct nr_neigh *nr_neigh)
342{
343	spin_lock_bh(&nr_neigh_list_lock);
344	__nr_remove_neigh(nr_neigh);
345	spin_unlock_bh(&nr_neigh_list_lock);
346}
347
348/*
349 *	"Delete" a node. Strictly speaking remove a route to a node. The node
350 *	is only deleted if no routes are left to it.
351 */
352static int nr_del_node(ax25_address *callsign, ax25_address *neighbour, struct net_device *dev)
353{
354	struct nr_node  *nr_node;
355	struct nr_neigh *nr_neigh;
356	int i;
357
358	nr_node = nr_node_get(callsign);
359
360	if (nr_node == NULL)
361		return -EINVAL;
362
363	nr_neigh = nr_neigh_get_dev(neighbour, dev);
364
365	if (nr_neigh == NULL) {
366		nr_node_put(nr_node);
367		return -EINVAL;
368	}
369
370	nr_node_lock(nr_node);
371	for (i = 0; i < nr_node->count; i++) {
372		if (nr_node->routes[i].neighbour == nr_neigh) {
373			nr_neigh->count--;
374			nr_neigh_put(nr_neigh);
375
376			if (nr_neigh->count == 0 && !nr_neigh->locked)
377				nr_remove_neigh(nr_neigh);
378			nr_neigh_put(nr_neigh);
379
380			nr_node->count--;
381
382			if (nr_node->count == 0) {
383				nr_remove_node(nr_node);
384			} else {
385				switch (i) {
386				case 0:
387					nr_node->routes[0] = nr_node->routes[1];
388				case 1:
389					nr_node->routes[1] = nr_node->routes[2];
390				case 2:
391					break;
392				}
393				nr_node_put(nr_node);
394			}
395			nr_node_unlock(nr_node);
396
397			return 0;
398		}
399	}
400	nr_neigh_put(nr_neigh);
401	nr_node_unlock(nr_node);
402	nr_node_put(nr_node);
403
404	return -EINVAL;
405}
406
407/*
408 *	Lock a neighbour with a quality.
409 */
410static int __must_check nr_add_neigh(ax25_address *callsign,
411	ax25_digi *ax25_digi, struct net_device *dev, unsigned int quality)
412{
413	struct nr_neigh *nr_neigh;
414
415	nr_neigh = nr_neigh_get_dev(callsign, dev);
416	if (nr_neigh) {
417		nr_neigh->quality = quality;
418		nr_neigh->locked  = 1;
419		nr_neigh_put(nr_neigh);
420		return 0;
421	}
422
423	if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL)
424		return -ENOMEM;
425
426	nr_neigh->callsign = *callsign;
427	nr_neigh->digipeat = NULL;
428	nr_neigh->ax25     = NULL;
429	nr_neigh->dev      = dev;
430	nr_neigh->quality  = quality;
431	nr_neigh->locked   = 1;
432	nr_neigh->count    = 0;
433	nr_neigh->number   = nr_neigh_no++;
434	nr_neigh->failed   = 0;
435	atomic_set(&nr_neigh->refcount, 1);
436
437	if (ax25_digi != NULL && ax25_digi->ndigi > 0) {
438		nr_neigh->digipeat = kmemdup(ax25_digi, sizeof(*ax25_digi),
439					     GFP_KERNEL);
440		if (nr_neigh->digipeat == NULL) {
441			kfree(nr_neigh);
442			return -ENOMEM;
443		}
444	}
445
446	spin_lock_bh(&nr_neigh_list_lock);
447	hlist_add_head(&nr_neigh->neigh_node, &nr_neigh_list);
448	/* refcount is initialized at 1 */
449	spin_unlock_bh(&nr_neigh_list_lock);
450
451	return 0;
452}
453
454/*
455 *	"Delete" a neighbour. The neighbour is only removed if the number
456 *	of nodes that may use it is zero.
457 */
458static int nr_del_neigh(ax25_address *callsign, struct net_device *dev, unsigned int quality)
459{
460	struct nr_neigh *nr_neigh;
461
462	nr_neigh = nr_neigh_get_dev(callsign, dev);
463
464	if (nr_neigh == NULL) return -EINVAL;
465
466	nr_neigh->quality = quality;
467	nr_neigh->locked  = 0;
468
469	if (nr_neigh->count == 0)
470		nr_remove_neigh(nr_neigh);
471	nr_neigh_put(nr_neigh);
472
473	return 0;
474}
475
476/*
477 *	Decrement the obsolescence count by one. If a route is reduced to a
478 *	count of zero, remove it. Also remove any unlocked neighbours with
479 *	zero nodes routing via it.
480 */
481static int nr_dec_obs(void)
482{
483	struct nr_neigh *nr_neigh;
484	struct nr_node  *s;
485	struct hlist_node *nodet;
486	int i;
487
488	spin_lock_bh(&nr_node_list_lock);
489	nr_node_for_each_safe(s, nodet, &nr_node_list) {
490		nr_node_lock(s);
491		for (i = 0; i < s->count; i++) {
492			switch (s->routes[i].obs_count) {
493			case 0:		/* A locked entry */
494				break;
495
496			case 1:		/* From 1 -> 0 */
497				nr_neigh = s->routes[i].neighbour;
498
499				nr_neigh->count--;
500				nr_neigh_put(nr_neigh);
501
502				if (nr_neigh->count == 0 && !nr_neigh->locked)
503					nr_remove_neigh(nr_neigh);
504
505				s->count--;
506
507				switch (i) {
508				case 0:
509					s->routes[0] = s->routes[1];
510					/* Fallthrough */
511				case 1:
512					s->routes[1] = s->routes[2];
513				case 2:
514					break;
515				}
516				break;
517
518			default:
519				s->routes[i].obs_count--;
520				break;
521
522			}
523		}
524
525		if (s->count <= 0)
526			nr_remove_node_locked(s);
527		nr_node_unlock(s);
528	}
529	spin_unlock_bh(&nr_node_list_lock);
530
531	return 0;
532}
533
534/*
535 *	A device has been removed. Remove its routes and neighbours.
536 */
537void nr_rt_device_down(struct net_device *dev)
538{
539	struct nr_neigh *s;
540	struct hlist_node *nodet, *node2t;
541	struct nr_node  *t;
542	int i;
543
544	spin_lock_bh(&nr_neigh_list_lock);
545	nr_neigh_for_each_safe(s, nodet, &nr_neigh_list) {
546		if (s->dev == dev) {
547			spin_lock_bh(&nr_node_list_lock);
548			nr_node_for_each_safe(t, node2t, &nr_node_list) {
549				nr_node_lock(t);
550				for (i = 0; i < t->count; i++) {
551					if (t->routes[i].neighbour == s) {
552						t->count--;
553
554						switch (i) {
555						case 0:
556							t->routes[0] = t->routes[1];
557						case 1:
558							t->routes[1] = t->routes[2];
559						case 2:
560							break;
561						}
562					}
563				}
564
565				if (t->count <= 0)
566					nr_remove_node_locked(t);
567				nr_node_unlock(t);
568			}
569			spin_unlock_bh(&nr_node_list_lock);
570
571			nr_remove_neigh_locked(s);
572		}
573	}
574	spin_unlock_bh(&nr_neigh_list_lock);
575}
576
577/*
578 *	Check that the device given is a valid AX.25 interface that is "up".
579 *	Or a valid ethernet interface with an AX.25 callsign binding.
580 */
581static struct net_device *nr_ax25_dev_get(char *devname)
582{
583	struct net_device *dev;
584
585	if ((dev = dev_get_by_name(&init_net, devname)) == NULL)
586		return NULL;
587
588	if ((dev->flags & IFF_UP) && dev->type == ARPHRD_AX25)
589		return dev;
590
591	dev_put(dev);
592	return NULL;
593}
594
595/*
596 *	Find the first active NET/ROM device, usually "nr0".
597 */
598struct net_device *nr_dev_first(void)
599{
600	struct net_device *dev, *first = NULL;
601
602	rcu_read_lock();
603	for_each_netdev_rcu(&init_net, dev) {
604		if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM)
605			if (first == NULL || strncmp(dev->name, first->name, 3) < 0)
606				first = dev;
607	}
608	if (first)
609		dev_hold(first);
610	rcu_read_unlock();
611
612	return first;
613}
614
615/*
616 *	Find the NET/ROM device for the given callsign.
617 */
618struct net_device *nr_dev_get(ax25_address *addr)
619{
620	struct net_device *dev;
621
622	rcu_read_lock();
623	for_each_netdev_rcu(&init_net, dev) {
624		if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM &&
625		    ax25cmp(addr, (ax25_address *)dev->dev_addr) == 0) {
626			dev_hold(dev);
627			goto out;
628		}
629	}
630	dev = NULL;
631out:
632	rcu_read_unlock();
633	return dev;
634}
635
636static ax25_digi *nr_call_to_digi(ax25_digi *digi, int ndigis,
637	ax25_address *digipeaters)
638{
639	int i;
640
641	if (ndigis == 0)
642		return NULL;
643
644	for (i = 0; i < ndigis; i++) {
645		digi->calls[i]    = digipeaters[i];
646		digi->repeated[i] = 0;
647	}
648
649	digi->ndigi      = ndigis;
650	digi->lastrepeat = -1;
651
652	return digi;
653}
654
655/*
656 *	Handle the ioctls that control the routing functions.
657 */
658int nr_rt_ioctl(unsigned int cmd, void __user *arg)
659{
660	struct nr_route_struct nr_route;
661	struct net_device *dev;
662	ax25_digi digi;
663	int ret;
664
665	switch (cmd) {
666	case SIOCADDRT:
667		if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct)))
668			return -EFAULT;
669		if (nr_route.ndigis > AX25_MAX_DIGIS)
670			return -EINVAL;
671		if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL)
672			return -EINVAL;
673		switch (nr_route.type) {
674		case NETROM_NODE:
675			if (strnlen(nr_route.mnemonic, 7) == 7) {
676				ret = -EINVAL;
677				break;
678			}
679
680			ret = nr_add_node(&nr_route.callsign,
681				nr_route.mnemonic,
682				&nr_route.neighbour,
683				nr_call_to_digi(&digi, nr_route.ndigis,
684						nr_route.digipeaters),
685				dev, nr_route.quality,
686				nr_route.obs_count);
687			break;
688		case NETROM_NEIGH:
689			ret = nr_add_neigh(&nr_route.callsign,
690				nr_call_to_digi(&digi, nr_route.ndigis,
691						nr_route.digipeaters),
692				dev, nr_route.quality);
693			break;
694		default:
695			ret = -EINVAL;
696		}
697		dev_put(dev);
698		return ret;
699
700	case SIOCDELRT:
701		if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct)))
702			return -EFAULT;
703		if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL)
704			return -EINVAL;
705		switch (nr_route.type) {
706		case NETROM_NODE:
707			ret = nr_del_node(&nr_route.callsign,
708				&nr_route.neighbour, dev);
709			break;
710		case NETROM_NEIGH:
711			ret = nr_del_neigh(&nr_route.callsign,
712				dev, nr_route.quality);
713			break;
714		default:
715			ret = -EINVAL;
716		}
717		dev_put(dev);
718		return ret;
719
720	case SIOCNRDECOBS:
721		return nr_dec_obs();
722
723	default:
724		return -EINVAL;
725	}
726
727	return 0;
728}
729
730/*
731 * 	A level 2 link has timed out, therefore it appears to be a poor link,
732 *	then don't use that neighbour until it is reset.
733 */
734void nr_link_failed(ax25_cb *ax25, int reason)
735{
736	struct nr_neigh *s, *nr_neigh = NULL;
737	struct nr_node  *nr_node = NULL;
738
739	spin_lock_bh(&nr_neigh_list_lock);
740	nr_neigh_for_each(s, &nr_neigh_list) {
741		if (s->ax25 == ax25) {
742			nr_neigh_hold(s);
743			nr_neigh = s;
744			break;
745		}
746	}
747	spin_unlock_bh(&nr_neigh_list_lock);
748
749	if (nr_neigh == NULL)
750		return;
751
752	nr_neigh->ax25 = NULL;
753	ax25_cb_put(ax25);
754
755	if (++nr_neigh->failed < sysctl_netrom_link_fails_count) {
756		nr_neigh_put(nr_neigh);
757		return;
758	}
759	spin_lock_bh(&nr_node_list_lock);
760	nr_node_for_each(nr_node, &nr_node_list) {
761		nr_node_lock(nr_node);
762		if (nr_node->which < nr_node->count &&
763		    nr_node->routes[nr_node->which].neighbour == nr_neigh)
764			nr_node->which++;
765		nr_node_unlock(nr_node);
766	}
767	spin_unlock_bh(&nr_node_list_lock);
768	nr_neigh_put(nr_neigh);
769}
770
771/*
772 *	Route a frame to an appropriate AX.25 connection. A NULL ax25_cb
773 *	indicates an internally generated frame.
774 */
775int nr_route_frame(struct sk_buff *skb, ax25_cb *ax25)
776{
777	ax25_address *nr_src, *nr_dest;
778	struct nr_neigh *nr_neigh;
779	struct nr_node  *nr_node;
780	struct net_device *dev;
781	unsigned char *dptr;
782	ax25_cb *ax25s;
783	int ret;
784	struct sk_buff *skbn;
785
786
787	nr_src  = (ax25_address *)(skb->data + 0);
788	nr_dest = (ax25_address *)(skb->data + 7);
789
790	if (ax25 != NULL) {
791		ret = nr_add_node(nr_src, "", &ax25->dest_addr, ax25->digipeat,
792				  ax25->ax25_dev->dev, 0,
793				  sysctl_netrom_obsolescence_count_initialiser);
794		if (ret)
795			return ret;
796	}
797
798	if ((dev = nr_dev_get(nr_dest)) != NULL) {	/* Its for me */
799		if (ax25 == NULL)			/* Its from me */
800			ret = nr_loopback_queue(skb);
801		else
802			ret = nr_rx_frame(skb, dev);
803		dev_put(dev);
804		return ret;
805	}
806
807	if (!sysctl_netrom_routing_control && ax25 != NULL)
808		return 0;
809
810	/* Its Time-To-Live has expired */
811	if (skb->data[14] == 1) {
812		return 0;
813	}
814
815	nr_node = nr_node_get(nr_dest);
816	if (nr_node == NULL)
817		return 0;
818	nr_node_lock(nr_node);
819
820	if (nr_node->which >= nr_node->count) {
821		nr_node_unlock(nr_node);
822		nr_node_put(nr_node);
823		return 0;
824	}
825
826	nr_neigh = nr_node->routes[nr_node->which].neighbour;
827
828	if ((dev = nr_dev_first()) == NULL) {
829		nr_node_unlock(nr_node);
830		nr_node_put(nr_node);
831		return 0;
832	}
833
834	/* We are going to change the netrom headers so we should get our
835	   own skb, we also did not know until now how much header space
836	   we had to reserve... - RXQ */
837	if ((skbn=skb_copy_expand(skb, dev->hard_header_len, 0, GFP_ATOMIC)) == NULL) {
838		nr_node_unlock(nr_node);
839		nr_node_put(nr_node);
840		dev_put(dev);
841		return 0;
842	}
843	kfree_skb(skb);
844	skb=skbn;
845	skb->data[14]--;
846
847	dptr  = skb_push(skb, 1);
848	*dptr = AX25_P_NETROM;
849
850	ax25s = nr_neigh->ax25;
851	nr_neigh->ax25 = ax25_send_frame(skb, 256,
852					 (ax25_address *)dev->dev_addr,
853					 &nr_neigh->callsign,
854					 nr_neigh->digipeat, nr_neigh->dev);
855	if (ax25s)
856		ax25_cb_put(ax25s);
857
858	dev_put(dev);
859	ret = (nr_neigh->ax25 != NULL);
860	nr_node_unlock(nr_node);
861	nr_node_put(nr_node);
862
863	return ret;
864}
865
866#ifdef CONFIG_PROC_FS
867
868static void *nr_node_start(struct seq_file *seq, loff_t *pos)
869{
870	spin_lock_bh(&nr_node_list_lock);
871	return seq_hlist_start_head(&nr_node_list, *pos);
872}
873
874static void *nr_node_next(struct seq_file *seq, void *v, loff_t *pos)
875{
876	return seq_hlist_next(v, &nr_node_list, pos);
877}
878
879static void nr_node_stop(struct seq_file *seq, void *v)
880{
881	spin_unlock_bh(&nr_node_list_lock);
882}
883
884static int nr_node_show(struct seq_file *seq, void *v)
885{
886	char buf[11];
887	int i;
888
889	if (v == SEQ_START_TOKEN)
890		seq_puts(seq,
891			 "callsign  mnemonic w n qual obs neigh qual obs neigh qual obs neigh\n");
892	else {
893		struct nr_node *nr_node = hlist_entry(v, struct nr_node,
894						      node_node);
895
896		nr_node_lock(nr_node);
897		seq_printf(seq, "%-9s %-7s  %d %d",
898			ax2asc(buf, &nr_node->callsign),
899			(nr_node->mnemonic[0] == '\0') ? "*" : nr_node->mnemonic,
900			nr_node->which + 1,
901			nr_node->count);
902
903		for (i = 0; i < nr_node->count; i++) {
904			seq_printf(seq, "  %3d   %d %05d",
905				nr_node->routes[i].quality,
906				nr_node->routes[i].obs_count,
907				nr_node->routes[i].neighbour->number);
908		}
909		nr_node_unlock(nr_node);
910
911		seq_puts(seq, "\n");
912	}
913	return 0;
914}
915
916static const struct seq_operations nr_node_seqops = {
917	.start = nr_node_start,
918	.next = nr_node_next,
919	.stop = nr_node_stop,
920	.show = nr_node_show,
921};
922
923static int nr_node_info_open(struct inode *inode, struct file *file)
924{
925	return seq_open(file, &nr_node_seqops);
926}
927
928const struct file_operations nr_nodes_fops = {
929	.owner = THIS_MODULE,
930	.open = nr_node_info_open,
931	.read = seq_read,
932	.llseek = seq_lseek,
933	.release = seq_release,
934};
935
936static void *nr_neigh_start(struct seq_file *seq, loff_t *pos)
937{
938	spin_lock_bh(&nr_neigh_list_lock);
939	return seq_hlist_start_head(&nr_neigh_list, *pos);
940}
941
942static void *nr_neigh_next(struct seq_file *seq, void *v, loff_t *pos)
943{
944	return seq_hlist_next(v, &nr_neigh_list, pos);
945}
946
947static void nr_neigh_stop(struct seq_file *seq, void *v)
948{
949	spin_unlock_bh(&nr_neigh_list_lock);
950}
951
952static int nr_neigh_show(struct seq_file *seq, void *v)
953{
954	char buf[11];
955	int i;
956
957	if (v == SEQ_START_TOKEN)
958		seq_puts(seq, "addr  callsign  dev  qual lock count failed digipeaters\n");
959	else {
960		struct nr_neigh *nr_neigh;
961
962		nr_neigh = hlist_entry(v, struct nr_neigh, neigh_node);
963		seq_printf(seq, "%05d %-9s %-4s  %3d    %d   %3d    %3d",
964			nr_neigh->number,
965			ax2asc(buf, &nr_neigh->callsign),
966			nr_neigh->dev ? nr_neigh->dev->name : "???",
967			nr_neigh->quality,
968			nr_neigh->locked,
969			nr_neigh->count,
970			nr_neigh->failed);
971
972		if (nr_neigh->digipeat != NULL) {
973			for (i = 0; i < nr_neigh->digipeat->ndigi; i++)
974				seq_printf(seq, " %s",
975					   ax2asc(buf, &nr_neigh->digipeat->calls[i]));
976		}
977
978		seq_puts(seq, "\n");
979	}
980	return 0;
981}
982
983static const struct seq_operations nr_neigh_seqops = {
984	.start = nr_neigh_start,
985	.next = nr_neigh_next,
986	.stop = nr_neigh_stop,
987	.show = nr_neigh_show,
988};
989
990static int nr_neigh_info_open(struct inode *inode, struct file *file)
991{
992	return seq_open(file, &nr_neigh_seqops);
993}
994
995const struct file_operations nr_neigh_fops = {
996	.owner = THIS_MODULE,
997	.open = nr_neigh_info_open,
998	.read = seq_read,
999	.llseek = seq_lseek,
1000	.release = seq_release,
1001};
1002
1003#endif
1004
1005/*
1006 *	Free all memory associated with the nodes and routes lists.
1007 */
1008void __exit nr_rt_free(void)
1009{
1010	struct nr_neigh *s = NULL;
1011	struct nr_node  *t = NULL;
1012	struct hlist_node *nodet;
1013
1014	spin_lock_bh(&nr_neigh_list_lock);
1015	spin_lock_bh(&nr_node_list_lock);
1016	nr_node_for_each_safe(t, nodet, &nr_node_list) {
1017		nr_node_lock(t);
1018		nr_remove_node_locked(t);
1019		nr_node_unlock(t);
1020	}
1021	nr_neigh_for_each_safe(s, nodet, &nr_neigh_list) {
1022		while(s->count) {
1023			s->count--;
1024			nr_neigh_put(s);
1025		}
1026		nr_remove_neigh_locked(s);
1027	}
1028	spin_unlock_bh(&nr_node_list_lock);
1029	spin_unlock_bh(&nr_neigh_list_lock);
1030}
1031