File: /usr/src/linux/net/netrom/nr_route.c

1     /*
2      *	NET/ROM release 007
3      *
4      *	This code REQUIRES 2.1.15 or higher/ NET3.038
5      *
6      *	This module:
7      *		This module is free software; you can redistribute it and/or
8      *		modify it under the terms of the GNU General Public License
9      *		as published by the Free Software Foundation; either version
10      *		2 of the License, or (at your option) any later version.
11      *
12      *	History
13      *	NET/ROM 001	Jonathan(G4KLX)	First attempt.
14      *	NET/ROM	003	Jonathan(G4KLX)	Use SIOCADDRT/SIOCDELRT ioctl values
15      *					for NET/ROM routes.
16      *					Use '*' for a blank mnemonic in /proc/net/nr_nodes.
17      *					Change default quality for new neighbour when same
18      *					as node callsign.
19      *			Alan Cox(GW4PTS) Added the firewall hooks.
20      *	NET/ROM 006	Jonathan(G4KLX)	Added the setting of digipeated neighbours.
21      *			Tomi(OH2BNS)	Routing quality and link failure changes.
22      */
23     
24     #include <linux/errno.h>
25     #include <linux/types.h>
26     #include <linux/socket.h>
27     #include <linux/in.h>
28     #include <linux/kernel.h>
29     #include <linux/sched.h>
30     #include <linux/timer.h>
31     #include <linux/string.h>
32     #include <linux/sockios.h>
33     #include <linux/net.h>
34     #include <net/ax25.h>
35     #include <linux/inet.h>
36     #include <linux/netdevice.h>
37     #include <net/arp.h>
38     #include <linux/if_arp.h>
39     #include <linux/skbuff.h>
40     #include <net/sock.h>
41     #include <asm/uaccess.h>
42     #include <asm/system.h>
43     #include <linux/fcntl.h>
44     #include <linux/termios.h>	/* For TIOCINQ/OUTQ */
45     #include <linux/mm.h>
46     #include <linux/interrupt.h>
47     #include <linux/notifier.h>
48     #include <linux/netfilter.h>
49     #include <linux/init.h>
50     #include <net/netrom.h>
51     
52     static unsigned int nr_neigh_no = 1;
53     
54     static struct nr_node  *nr_node_list;
55     static struct nr_neigh *nr_neigh_list;
56     
57     static void nr_remove_neigh(struct nr_neigh *);
58     
59     /*
60      *	Add a new route to a node, and in the process add the node and the
61      *	neighbour if it is new.
62      */
63     static int nr_add_node(ax25_address *nr, const char *mnemonic, ax25_address *ax25,
64     	ax25_digi *ax25_digi, struct net_device *dev, int quality, int obs_count)
65     {
66     	struct nr_node  *nr_node;
67     	struct nr_neigh *nr_neigh;
68     	struct nr_route nr_route;
69     	unsigned long flags;
70     	int i, found;
71     
72     	if (nr_dev_get(nr) != NULL)	/* Can't add routes to ourself */
73     		return -EINVAL;
74     
75     	for (nr_node = nr_node_list; nr_node != NULL; nr_node = nr_node->next)
76     		if (ax25cmp(nr, &nr_node->callsign) == 0)
77     			break;
78     
79     	for (nr_neigh = nr_neigh_list; nr_neigh != NULL; nr_neigh = nr_neigh->next)
80     		if (ax25cmp(ax25, &nr_neigh->callsign) == 0 && nr_neigh->dev == dev)
81     			break;
82     
83     	/*
84     	 * The L2 link to a neighbour has failed in the past
85     	 * and now a frame comes from this neighbour. We assume
86     	 * it was a temporary trouble with the link and reset the
87     	 * routes now (and not wait for a node broadcast).
88     	 */
89     	if (nr_neigh != NULL && nr_neigh->failed != 0 && quality == 0) {
90     		struct nr_node *node;
91     
92     		for (node = nr_node_list; node != NULL; node = node->next)
93     			for (i = 0; i < node->count; i++)
94     				if (node->routes[i].neighbour == nr_neigh)
95     					if (i < node->which)
96     						node->which = i;
97     	}
98     
99     	if (nr_neigh != NULL)
100     		nr_neigh->failed = 0;
101     
102     	if (quality == 0 && nr_neigh != NULL && nr_node != NULL)
103     		return 0;
104     
105     	if (nr_neigh == NULL) {
106     		if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL)
107     			return -ENOMEM;
108     
109     		nr_neigh->callsign = *ax25;
110     		nr_neigh->digipeat = NULL;
111     		nr_neigh->ax25     = NULL;
112     		nr_neigh->dev      = dev;
113     		nr_neigh->quality  = sysctl_netrom_default_path_quality;
114     		nr_neigh->locked   = 0;
115     		nr_neigh->count    = 0;
116     		nr_neigh->number   = nr_neigh_no++;
117     		nr_neigh->failed   = 0;
118     
119     		if (ax25_digi != NULL && ax25_digi->ndigi > 0) {
120     			if ((nr_neigh->digipeat = kmalloc(sizeof(*ax25_digi), GFP_KERNEL)) == NULL) {
121     				kfree(nr_neigh);
122     				return -ENOMEM;
123     			}
124     			memcpy(nr_neigh->digipeat, ax25_digi, sizeof(ax25_digi));
125     		}
126     
127     		save_flags(flags);
128     		cli();
129     
130     		nr_neigh->next = nr_neigh_list;
131     		nr_neigh_list  = nr_neigh;
132     
133     		restore_flags(flags);
134     	}
135     
136     	if (quality != 0 && ax25cmp(nr, ax25) == 0 && !nr_neigh->locked)
137     		nr_neigh->quality = quality;
138     
139     	if (nr_node == NULL) {
140     		if ((nr_node = kmalloc(sizeof(*nr_node), GFP_ATOMIC)) == NULL)
141     			return -ENOMEM;
142     
143     		nr_node->callsign = *nr;
144     		strcpy(nr_node->mnemonic, mnemonic);
145     
146     		nr_node->which = 0;
147     		nr_node->count = 1;
148     
149     		nr_node->routes[0].quality   = quality;
150     		nr_node->routes[0].obs_count = obs_count;
151     		nr_node->routes[0].neighbour = nr_neigh;
152     
153     		save_flags(flags);
154     		cli();
155     
156     		nr_node->next = nr_node_list;
157     		nr_node_list  = nr_node;
158     
159     		restore_flags(flags);
160     
161     		nr_neigh->count++;
162     
163     		return 0;
164     	}
165     
166     	if (quality != 0)
167     		strcpy(nr_node->mnemonic, mnemonic);
168     
169     	for (found = 0, i = 0; i < nr_node->count; i++) {
170     		if (nr_node->routes[i].neighbour == nr_neigh) {
171     			nr_node->routes[i].quality   = quality;
172     			nr_node->routes[i].obs_count = obs_count;
173     			found = 1;
174     			break;
175     		}
176     	}
177     
178     	if (!found) {
179     		/* We have space at the bottom, slot it in */
180     		if (nr_node->count < 3) {
181     			nr_node->routes[2] = nr_node->routes[1];
182     			nr_node->routes[1] = nr_node->routes[0];
183     
184     			nr_node->routes[0].quality   = quality;
185     			nr_node->routes[0].obs_count = obs_count;
186     			nr_node->routes[0].neighbour = nr_neigh;
187     
188     			nr_node->which++;
189     			nr_node->count++;
190     			nr_neigh->count++;
191     		} else {
192     			/* It must be better than the worst */
193     			if (quality > nr_node->routes[2].quality) {
194     				nr_node->routes[2].neighbour->count--;
195     
196     				if (nr_node->routes[2].neighbour->count == 0 && !nr_node->routes[2].neighbour->locked)
197     					nr_remove_neigh(nr_node->routes[2].neighbour);
198     
199     				nr_node->routes[2].quality   = quality;
200     				nr_node->routes[2].obs_count = obs_count;
201     				nr_node->routes[2].neighbour = nr_neigh;
202     
203     				nr_neigh->count++;
204     			}
205     		}
206     	}
207     
208     	/* Now re-sort the routes in quality order */
209     	switch (nr_node->count) {
210     		case 3:
211     			if (nr_node->routes[1].quality > nr_node->routes[0].quality) {
212     				switch (nr_node->which) {
213     					case 0:  nr_node->which = 1; break;
214     					case 1:  nr_node->which = 0; break;
215     					default: break;
216     				}
217     				nr_route           = nr_node->routes[0];
218     				nr_node->routes[0] = nr_node->routes[1];
219     				nr_node->routes[1] = nr_route;
220     			}
221     			if (nr_node->routes[2].quality > nr_node->routes[1].quality) {
222     				switch (nr_node->which) {
223     					case 1:  nr_node->which = 2; break;
224     					case 2:  nr_node->which = 1; break;
225     					default: break;
226     				}
227     				nr_route           = nr_node->routes[1];
228     				nr_node->routes[1] = nr_node->routes[2];
229     				nr_node->routes[2] = nr_route;
230     			}
231     		case 2:
232     			if (nr_node->routes[1].quality > nr_node->routes[0].quality) {
233     				switch (nr_node->which) {
234     					case 0:  nr_node->which = 1; break;
235     					case 1:  nr_node->which = 0; break;
236     					default: break;
237     				}
238     				nr_route           = nr_node->routes[0];
239     				nr_node->routes[0] = nr_node->routes[1];
240     				nr_node->routes[1] = nr_route;
241     			}
242     		case 1:
243     			break;
244     	}
245     
246     	for (i = 0; i < nr_node->count; i++) {
247     		if (nr_node->routes[i].neighbour == nr_neigh) {
248     			if (i < nr_node->which)
249     				nr_node->which = i;
250     			break;
251     		}
252     	}
253     
254     	return 0;
255     }
256     
257     static void nr_remove_node(struct nr_node *nr_node)
258     {
259     	struct nr_node *s;
260     	unsigned long flags;
261     
262     	save_flags(flags);
263     	cli();
264     
265     	if ((s = nr_node_list) == nr_node) {
266     		nr_node_list = nr_node->next;
267     		restore_flags(flags);
268     		kfree(nr_node);
269     		return;
270     	}
271     
272     	while (s != NULL && s->next != NULL) {
273     		if (s->next == nr_node) {
274     			s->next = nr_node->next;
275     			restore_flags(flags);
276     			kfree(nr_node);
277     			return;
278     		}
279     
280     		s = s->next;
281     	}
282     
283     	restore_flags(flags);
284     }
285     
286     static void nr_remove_neigh(struct nr_neigh *nr_neigh)
287     {
288     	struct nr_neigh *s;
289     	unsigned long flags;
290     	
291     	save_flags(flags);
292     	cli();
293     
294     	if ((s = nr_neigh_list) == nr_neigh) {
295     		nr_neigh_list = nr_neigh->next;
296     		restore_flags(flags);
297     		if (nr_neigh->digipeat != NULL)
298     			kfree(nr_neigh->digipeat);
299     		kfree(nr_neigh);
300     		return;
301     	}
302     
303     	while (s != NULL && s->next != NULL) {
304     		if (s->next == nr_neigh) {
305     			s->next = nr_neigh->next;
306     			restore_flags(flags);
307     			if (nr_neigh->digipeat != NULL)
308     				kfree(nr_neigh->digipeat);
309     			kfree(nr_neigh);
310     			return;
311     		}
312     
313     		s = s->next;
314     	}
315     
316     	restore_flags(flags);
317     }
318     
319     /*
320      *	"Delete" a node. Strictly speaking remove a route to a node. The node
321      *	is only deleted if no routes are left to it.
322      */
323     static int nr_del_node(ax25_address *callsign, ax25_address *neighbour, struct net_device *dev)
324     {
325     	struct nr_node  *nr_node;
326     	struct nr_neigh *nr_neigh;
327     	int i;
328     
329     	for (nr_node = nr_node_list; nr_node != NULL; nr_node = nr_node->next)
330     		if (ax25cmp(callsign, &nr_node->callsign) == 0)
331     			break;
332     
333     	if (nr_node == NULL) return -EINVAL;
334     
335     	for (nr_neigh = nr_neigh_list; nr_neigh != NULL; nr_neigh = nr_neigh->next)
336     		if (ax25cmp(neighbour, &nr_neigh->callsign) == 0 && nr_neigh->dev == dev)
337     			break;
338     
339     	if (nr_neigh == NULL) return -EINVAL;
340     
341     	for (i = 0; i < nr_node->count; i++) {
342     		if (nr_node->routes[i].neighbour == nr_neigh) {
343     			nr_neigh->count--;
344     
345     			if (nr_neigh->count == 0 && !nr_neigh->locked)
346     				nr_remove_neigh(nr_neigh);
347     
348     			nr_node->count--;
349     
350     			if (nr_node->count == 0) {
351     				nr_remove_node(nr_node);
352     			} else {
353     				switch (i) {
354     					case 0:
355     						nr_node->routes[0] = nr_node->routes[1];
356     					case 1:
357     						nr_node->routes[1] = nr_node->routes[2];
358     					case 2:
359     						break;
360     				}
361     			}
362     
363     			return 0;
364     		}
365     	}
366     
367     	return -EINVAL;
368     }
369     
370     /*
371      *	Lock a neighbour with a quality.
372      */
373     static int nr_add_neigh(ax25_address *callsign, ax25_digi *ax25_digi, struct net_device *dev, unsigned int quality)
374     {
375     	struct nr_neigh *nr_neigh;
376     	unsigned long flags;
377     
378     	for (nr_neigh = nr_neigh_list; nr_neigh != NULL; nr_neigh = nr_neigh->next) {
379     		if (ax25cmp(callsign, &nr_neigh->callsign) == 0 && nr_neigh->dev == dev) {
380     			nr_neigh->quality = quality;
381     			nr_neigh->locked  = 1;
382     			return 0;
383     		}
384     	}
385     
386     	if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL)
387     		return -ENOMEM;
388     
389     	nr_neigh->callsign = *callsign;
390     	nr_neigh->digipeat = NULL;
391     	nr_neigh->ax25     = NULL;
392     	nr_neigh->dev      = dev;
393     	nr_neigh->quality  = quality;
394     	nr_neigh->locked   = 1;
395     	nr_neigh->count    = 0;
396     	nr_neigh->number   = nr_neigh_no++;
397     	nr_neigh->failed   = 0;
398     
399     	if (ax25_digi != NULL && ax25_digi->ndigi > 0) {
400     		if ((nr_neigh->digipeat = kmalloc(sizeof(*ax25_digi), GFP_KERNEL)) == NULL) {
401     			kfree(nr_neigh);
402     			return -ENOMEM;
403     		}
404     		memcpy(nr_neigh->digipeat, ax25_digi, sizeof(ax25_digi));
405     	}
406     
407     	save_flags(flags);
408     	cli();
409     
410     	nr_neigh->next = nr_neigh_list;
411     	nr_neigh_list  = nr_neigh;
412     
413     	restore_flags(flags);
414     
415     	return 0;	
416     }
417     
418     /*
419      *	"Delete" a neighbour. The neighbour is only removed if the number
420      *	of nodes that may use it is zero.
421      */
422     static int nr_del_neigh(ax25_address *callsign, struct net_device *dev, unsigned int quality)
423     {
424     	struct nr_neigh *nr_neigh;
425     
426     	for (nr_neigh = nr_neigh_list; nr_neigh != NULL; nr_neigh = nr_neigh->next)
427     		if (ax25cmp(callsign, &nr_neigh->callsign) == 0 && nr_neigh->dev == dev)
428     			break;
429     
430     	if (nr_neigh == NULL) return -EINVAL;
431     
432     	nr_neigh->quality = quality;
433     	nr_neigh->locked  = 0;
434     
435     	if (nr_neigh->count == 0)
436     		nr_remove_neigh(nr_neigh);
437     
438     	return 0;
439     }
440     
441     /*
442      *	Decrement the obsolescence count by one. If a route is reduced to a
443      *	count of zero, remove it. Also remove any unlocked neighbours with
444      *	zero nodes routing via it.
445      */
446     static int nr_dec_obs(void)
447     {
448     	struct nr_neigh *nr_neigh;
449     	struct nr_node  *s, *nr_node;
450     	int i;
451     
452     	nr_node = nr_node_list;
453     
454     	while (nr_node != NULL) {
455     		s       = nr_node;
456     		nr_node = nr_node->next;
457     
458     		for (i = 0; i < s->count; i++) {
459     			switch (s->routes[i].obs_count) {
460     
461     			case 0:		/* A locked entry */
462     				break;
463     
464     			case 1:		/* From 1 -> 0 */
465     				nr_neigh = s->routes[i].neighbour;
466     
467     				nr_neigh->count--;
468     
469     				if (nr_neigh->count == 0 && !nr_neigh->locked)
470     					nr_remove_neigh(nr_neigh);
471     
472     				s->count--;
473     
474     				switch (i) {
475     					case 0:
476     						s->routes[0] = s->routes[1];
477     					case 1:
478     						s->routes[1] = s->routes[2];
479     					case 2:
480     						break;
481     				}
482     				break;
483     
484     			default:
485     				s->routes[i].obs_count--;
486     				break;
487     
488     			}
489     		}
490     
491     		if (s->count <= 0)
492     			nr_remove_node(s);
493     	}
494     
495     	return 0;
496     }
497     
498     /*
499      *	A device has been removed. Remove its routes and neighbours.
500      */
501     void nr_rt_device_down(struct net_device *dev)
502     {
503     	struct nr_neigh *s, *nr_neigh = nr_neigh_list;
504     	struct nr_node  *t, *nr_node;
505     	int i;
506     
507     	while (nr_neigh != NULL) {
508     		s        = nr_neigh;
509     		nr_neigh = nr_neigh->next;
510     
511     		if (s->dev == dev) {
512     			nr_node = nr_node_list;
513     
514     			while (nr_node != NULL) {
515     				t       = nr_node;
516     				nr_node = nr_node->next;
517     
518     				for (i = 0; i < t->count; i++) {
519     					if (t->routes[i].neighbour == s) {
520     						t->count--;
521     
522     						switch (i) {
523     							case 0:
524     								t->routes[0] = t->routes[1];
525     							case 1:
526     								t->routes[1] = t->routes[2];
527     							case 2:
528     								break;
529     						}
530     					}
531     				}
532     
533     				if (t->count <= 0)
534     					nr_remove_node(t);
535     			}
536     
537     			nr_remove_neigh(s);
538     		}
539     	}
540     }
541     
542     /*
543      *	Check that the device given is a valid AX.25 interface that is "up".
544      *	Or a valid ethernet interface with an AX.25 callsign binding.
545      */
546     static struct net_device *nr_ax25_dev_get(char *devname)
547     {
548     	struct net_device *dev;
549     
550     	if ((dev = dev_get_by_name(devname)) == NULL)
551     		return NULL;
552     
553     	if ((dev->flags & IFF_UP) && dev->type == ARPHRD_AX25)
554     		return dev;
555     
556     	dev_put(dev);
557     	return NULL;
558     }
559     
560     /*
561      *	Find the first active NET/ROM device, usually "nr0".
562      */
563     struct net_device *nr_dev_first(void)
564     {
565     	struct net_device *dev, *first = NULL;
566     
567     	read_lock(&dev_base_lock);
568     	for (dev = dev_base; dev != NULL; dev = dev->next) {
569     		if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM)
570     			if (first == NULL || strncmp(dev->name, first->name, 3) < 0)
571     				first = dev;
572     	}
573     	read_unlock(&dev_base_lock);
574     
575     	return first;
576     }
577     
578     /*
579      *	Find the NET/ROM device for the given callsign.
580      */
581     struct net_device *nr_dev_get(ax25_address *addr)
582     {
583     	struct net_device *dev;
584     
585     	read_lock(&dev_base_lock);
586     	for (dev = dev_base; dev != NULL; dev = dev->next) {
587     		if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM && ax25cmp(addr, (ax25_address *)dev->dev_addr) == 0) {
588     			dev_hold(dev);
589     			goto out;
590     		}
591     	}
592     out:
593     	read_unlock(&dev_base_lock);
594     	return dev;
595     }
596     
597     static ax25_digi *nr_call_to_digi(int ndigis, ax25_address *digipeaters)
598     {
599     	static ax25_digi ax25_digi;
600     	int i;
601     
602     	if (ndigis == 0)
603     		return NULL;
604     
605     	for (i = 0; i < ndigis; i++) {
606     		ax25_digi.calls[i]    = digipeaters[i];
607     		ax25_digi.repeated[i] = 0;
608     	}
609     
610     	ax25_digi.ndigi      = ndigis;
611     	ax25_digi.lastrepeat = -1;
612     
613     	return &ax25_digi;
614     }
615     
616     /*
617      *	Handle the ioctls that control the routing functions.
618      */
619     int nr_rt_ioctl(unsigned int cmd, void *arg)
620     {
621     	struct nr_route_struct nr_route;
622     	struct net_device *dev;
623     
624     	switch (cmd) {
625     
626     		case SIOCADDRT:
627     			if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct)))
628     				return -EFAULT;
629     			if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL)
630     				return -EINVAL;
631     			if (nr_route.ndigis < 0 || nr_route.ndigis > AX25_MAX_DIGIS)
632     				return -EINVAL;
633     			switch (nr_route.type) {
634     				case NETROM_NODE:
635     					return nr_add_node(&nr_route.callsign,
636     						nr_route.mnemonic,
637     						&nr_route.neighbour,
638     						nr_call_to_digi(nr_route.ndigis, nr_route.digipeaters),
639     						dev, nr_route.quality,
640     						nr_route.obs_count);
641     				case NETROM_NEIGH:
642     					return nr_add_neigh(&nr_route.callsign,
643     						nr_call_to_digi(nr_route.ndigis, nr_route.digipeaters),
644     						dev, nr_route.quality);
645     				default:
646     					return -EINVAL;
647     			}
648     
649     		case SIOCDELRT:
650     			if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct)))
651     				return -EFAULT;
652     			if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL)
653     				return -EINVAL;
654     			switch (nr_route.type) {
655     				case NETROM_NODE:
656     					return nr_del_node(&nr_route.callsign,
657     						&nr_route.neighbour, dev);
658     				case NETROM_NEIGH:
659     					return nr_del_neigh(&nr_route.callsign,
660     						dev, nr_route.quality);
661     				default:
662     					return -EINVAL;
663     			}
664     
665     		case SIOCNRDECOBS:
666     			return nr_dec_obs();
667     
668     		default:
669     			return -EINVAL;
670     	}
671     
672     	return 0;
673     }
674     
675     /*
676      * 	A level 2 link has timed out, therefore it appears to be a poor link,
677      *	then don't use that neighbour until it is reset.
678      */
679     void nr_link_failed(ax25_cb *ax25, int reason)
680     {
681     	struct nr_neigh *nr_neigh;
682     	struct nr_node  *nr_node;
683     
684     	for (nr_neigh = nr_neigh_list; nr_neigh != NULL; nr_neigh = nr_neigh->next)
685     		if (nr_neigh->ax25 == ax25)
686     			break;
687     
688     	if (nr_neigh == NULL) return;
689     
690     	nr_neigh->ax25 = NULL;
691     
692     	if (++nr_neigh->failed < sysctl_netrom_link_fails_count) return;
693     
694     	for (nr_node = nr_node_list; nr_node != NULL; nr_node = nr_node->next)
695     		if (nr_node->which < nr_node->count && nr_node->routes[nr_node->which].neighbour == nr_neigh)
696     			nr_node->which++;
697     }
698     
699     /*
700      *	Route a frame to an appropriate AX.25 connection. A NULL ax25_cb
701      *	indicates an internally generated frame.
702      */
703     int nr_route_frame(struct sk_buff *skb, ax25_cb *ax25)
704     {
705     	ax25_address *nr_src, *nr_dest;
706     	struct nr_neigh *nr_neigh;
707     	struct nr_node  *nr_node;
708     	struct net_device *dev;
709     	unsigned char *dptr;
710     
711     
712     	nr_src  = (ax25_address *)(skb->data + 0);
713     	nr_dest = (ax25_address *)(skb->data + 7);
714     
715     	if (ax25 != NULL)
716     		nr_add_node(nr_src, "", &ax25->dest_addr, ax25->digipeat,
717     			    ax25->ax25_dev->dev, 0, sysctl_netrom_obsolescence_count_initialiser);
718     
719     	if ((dev = nr_dev_get(nr_dest)) != NULL) {	/* Its for me */
720     		if (ax25 == NULL)			/* Its from me */
721     			return nr_loopback_queue(skb);
722     		else
723     			return nr_rx_frame(skb, dev);
724     	}
725     
726     	if (!sysctl_netrom_routing_control && ax25 != NULL)
727     		return 0;
728     
729     	/* Its Time-To-Live has expired */
730     	if (--skb->data[14] == 0)
731     		return 0;
732     
733     	for (nr_node = nr_node_list; nr_node != NULL; nr_node = nr_node->next)
734     		if (ax25cmp(nr_dest, &nr_node->callsign) == 0)
735     			break;
736     
737     	if (nr_node == NULL || nr_node->which >= nr_node->count)
738     		return 0;
739     
740     	nr_neigh = nr_node->routes[nr_node->which].neighbour;
741     
742     	if ((dev = nr_dev_first()) == NULL)
743     		return 0;
744     
745     	dptr  = skb_push(skb, 1);
746     	*dptr = AX25_P_NETROM;
747     
748     	nr_neigh->ax25 = ax25_send_frame(skb, 256, (ax25_address *)dev->dev_addr, &nr_neigh->callsign, nr_neigh->digipeat, nr_neigh->dev);
749     
750     	return (nr_neigh->ax25 != NULL);
751     }
752     
753     int nr_nodes_get_info(char *buffer, char **start, off_t offset, int length)
754     {
755     	struct nr_node *nr_node;
756     	int len     = 0;
757     	off_t pos   = 0;
758     	off_t begin = 0;
759     	int i;
760     
761     	cli();
762     
763     	len += sprintf(buffer, "callsign  mnemonic w n qual obs neigh qual obs neigh qual obs neigh\n");
764     
765     	for (nr_node = nr_node_list; nr_node != NULL; nr_node = nr_node->next) {
766     		len += sprintf(buffer + len, "%-9s %-7s  %d %d",
767     			ax2asc(&nr_node->callsign),
768     			(nr_node->mnemonic[0] == '\0') ? "*" : nr_node->mnemonic,
769     			nr_node->which + 1,
770     			nr_node->count);			
771     
772     		for (i = 0; i < nr_node->count; i++) {
773     			len += sprintf(buffer + len, "  %3d   %d %05d",
774     				nr_node->routes[i].quality,
775     				nr_node->routes[i].obs_count,
776     				nr_node->routes[i].neighbour->number);
777     		}
778     
779     		len += sprintf(buffer + len, "\n");
780     
781     		pos = begin + len;
782     
783     		if (pos < offset) {
784     			len   = 0;
785     			begin = pos;
786     		}
787     
788     		if (pos > offset + length)
789     			break;
790     	}
791     
792     	sti();
793     
794     	*start = buffer + (offset - begin);
795     	len   -= (offset - begin);
796     
797     	if (len > length) len = length;
798     
799     	return len;
800     } 
801     
802     int nr_neigh_get_info(char *buffer, char **start, off_t offset, int length)
803     {
804     	struct nr_neigh *nr_neigh;
805     	int len     = 0;
806     	off_t pos   = 0;
807     	off_t begin = 0;
808     	int i;
809     
810     	cli();
811     
812     	len += sprintf(buffer, "addr  callsign  dev  qual lock count failed digipeaters\n");
813     
814     	for (nr_neigh = nr_neigh_list; nr_neigh != NULL; nr_neigh = nr_neigh->next) {
815     		len += sprintf(buffer + len, "%05d %-9s %-4s  %3d    %d   %3d    %3d",
816     			nr_neigh->number,
817     			ax2asc(&nr_neigh->callsign),
818     			nr_neigh->dev ? nr_neigh->dev->name : "???",
819     			nr_neigh->quality,
820     			nr_neigh->locked,
821     			nr_neigh->count,
822     			nr_neigh->failed);
823     
824     		if (nr_neigh->digipeat != NULL) {
825     			for (i = 0; i < nr_neigh->digipeat->ndigi; i++)
826     				len += sprintf(buffer + len, " %s", ax2asc(&nr_neigh->digipeat->calls[i]));
827     		}
828     
829     		len += sprintf(buffer + len, "\n");
830     
831     		pos = begin + len;
832     
833     		if (pos < offset) {
834     			len   = 0;
835     			begin = pos;
836     		}
837     
838     		if (pos > offset + length)
839     			break;
840     	}
841     
842     	sti();
843     
844     	*start = buffer + (offset - begin);
845     	len   -= (offset - begin);
846     
847     	if (len > length) len = length;
848     
849     	return len;
850     } 
851     
852     /*
853      *	Free all memory associated with the nodes and routes lists.
854      */
855     void __exit nr_rt_free(void)
856     {
857     	struct nr_neigh *s, *nr_neigh = nr_neigh_list;
858     	struct nr_node  *t, *nr_node  = nr_node_list;
859     
860     	while (nr_node != NULL) {
861     		t       = nr_node;
862     		nr_node = nr_node->next;
863     
864     		nr_remove_node(t);
865     	}
866     
867     	while (nr_neigh != NULL) {
868     		s        = nr_neigh;
869     		nr_neigh = nr_neigh->next;
870     
871     		nr_remove_neigh(s);
872     	}
873     }
874