xref: /OK3568_Linux_fs/kernel/net/netrom/nr_route.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-or-later
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  *
4*4882a593Smuzhiyun  * Copyright Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
5*4882a593Smuzhiyun  * Copyright Alan Cox GW4PTS (alan@lxorguk.ukuu.org.uk)
6*4882a593Smuzhiyun  * Copyright Tomi Manninen OH2BNS (oh2bns@sral.fi)
7*4882a593Smuzhiyun  */
8*4882a593Smuzhiyun #include <linux/errno.h>
9*4882a593Smuzhiyun #include <linux/types.h>
10*4882a593Smuzhiyun #include <linux/socket.h>
11*4882a593Smuzhiyun #include <linux/in.h>
12*4882a593Smuzhiyun #include <linux/kernel.h>
13*4882a593Smuzhiyun #include <linux/timer.h>
14*4882a593Smuzhiyun #include <linux/string.h>
15*4882a593Smuzhiyun #include <linux/sockios.h>
16*4882a593Smuzhiyun #include <linux/net.h>
17*4882a593Smuzhiyun #include <linux/slab.h>
18*4882a593Smuzhiyun #include <net/ax25.h>
19*4882a593Smuzhiyun #include <linux/inet.h>
20*4882a593Smuzhiyun #include <linux/netdevice.h>
21*4882a593Smuzhiyun #include <net/arp.h>
22*4882a593Smuzhiyun #include <linux/if_arp.h>
23*4882a593Smuzhiyun #include <linux/skbuff.h>
24*4882a593Smuzhiyun #include <net/sock.h>
25*4882a593Smuzhiyun #include <linux/uaccess.h>
26*4882a593Smuzhiyun #include <linux/fcntl.h>
27*4882a593Smuzhiyun #include <linux/termios.h>	/* For TIOCINQ/OUTQ */
28*4882a593Smuzhiyun #include <linux/mm.h>
29*4882a593Smuzhiyun #include <linux/interrupt.h>
30*4882a593Smuzhiyun #include <linux/notifier.h>
31*4882a593Smuzhiyun #include <linux/init.h>
32*4882a593Smuzhiyun #include <linux/spinlock.h>
33*4882a593Smuzhiyun #include <net/netrom.h>
34*4882a593Smuzhiyun #include <linux/seq_file.h>
35*4882a593Smuzhiyun #include <linux/export.h>
36*4882a593Smuzhiyun 
37*4882a593Smuzhiyun static unsigned int nr_neigh_no = 1;
38*4882a593Smuzhiyun 
39*4882a593Smuzhiyun static HLIST_HEAD(nr_node_list);
40*4882a593Smuzhiyun static DEFINE_SPINLOCK(nr_node_list_lock);
41*4882a593Smuzhiyun static HLIST_HEAD(nr_neigh_list);
42*4882a593Smuzhiyun static DEFINE_SPINLOCK(nr_neigh_list_lock);
43*4882a593Smuzhiyun 
nr_node_get(ax25_address * callsign)44*4882a593Smuzhiyun static struct nr_node *nr_node_get(ax25_address *callsign)
45*4882a593Smuzhiyun {
46*4882a593Smuzhiyun 	struct nr_node *found = NULL;
47*4882a593Smuzhiyun 	struct nr_node *nr_node;
48*4882a593Smuzhiyun 
49*4882a593Smuzhiyun 	spin_lock_bh(&nr_node_list_lock);
50*4882a593Smuzhiyun 	nr_node_for_each(nr_node, &nr_node_list)
51*4882a593Smuzhiyun 		if (ax25cmp(callsign, &nr_node->callsign) == 0) {
52*4882a593Smuzhiyun 			nr_node_hold(nr_node);
53*4882a593Smuzhiyun 			found = nr_node;
54*4882a593Smuzhiyun 			break;
55*4882a593Smuzhiyun 		}
56*4882a593Smuzhiyun 	spin_unlock_bh(&nr_node_list_lock);
57*4882a593Smuzhiyun 	return found;
58*4882a593Smuzhiyun }
59*4882a593Smuzhiyun 
nr_neigh_get_dev(ax25_address * callsign,struct net_device * dev)60*4882a593Smuzhiyun static struct nr_neigh *nr_neigh_get_dev(ax25_address *callsign,
61*4882a593Smuzhiyun 					 struct net_device *dev)
62*4882a593Smuzhiyun {
63*4882a593Smuzhiyun 	struct nr_neigh *found = NULL;
64*4882a593Smuzhiyun 	struct nr_neigh *nr_neigh;
65*4882a593Smuzhiyun 
66*4882a593Smuzhiyun 	spin_lock_bh(&nr_neigh_list_lock);
67*4882a593Smuzhiyun 	nr_neigh_for_each(nr_neigh, &nr_neigh_list)
68*4882a593Smuzhiyun 		if (ax25cmp(callsign, &nr_neigh->callsign) == 0 &&
69*4882a593Smuzhiyun 		    nr_neigh->dev == dev) {
70*4882a593Smuzhiyun 			nr_neigh_hold(nr_neigh);
71*4882a593Smuzhiyun 			found = nr_neigh;
72*4882a593Smuzhiyun 			break;
73*4882a593Smuzhiyun 		}
74*4882a593Smuzhiyun 	spin_unlock_bh(&nr_neigh_list_lock);
75*4882a593Smuzhiyun 	return found;
76*4882a593Smuzhiyun }
77*4882a593Smuzhiyun 
78*4882a593Smuzhiyun static void nr_remove_neigh(struct nr_neigh *);
79*4882a593Smuzhiyun 
80*4882a593Smuzhiyun /*      re-sort the routes in quality order.    */
re_sort_routes(struct nr_node * nr_node,int x,int y)81*4882a593Smuzhiyun static void re_sort_routes(struct nr_node *nr_node, int x, int y)
82*4882a593Smuzhiyun {
83*4882a593Smuzhiyun 	if (nr_node->routes[y].quality > nr_node->routes[x].quality) {
84*4882a593Smuzhiyun 		if (nr_node->which == x)
85*4882a593Smuzhiyun 			nr_node->which = y;
86*4882a593Smuzhiyun 		else if (nr_node->which == y)
87*4882a593Smuzhiyun 			nr_node->which = x;
88*4882a593Smuzhiyun 
89*4882a593Smuzhiyun 		swap(nr_node->routes[x], nr_node->routes[y]);
90*4882a593Smuzhiyun 	}
91*4882a593Smuzhiyun }
92*4882a593Smuzhiyun 
93*4882a593Smuzhiyun /*
94*4882a593Smuzhiyun  *	Add a new route to a node, and in the process add the node and the
95*4882a593Smuzhiyun  *	neighbour if it is new.
96*4882a593Smuzhiyun  */
nr_add_node(ax25_address * nr,const char * mnemonic,ax25_address * ax25,ax25_digi * ax25_digi,struct net_device * dev,int quality,int obs_count)97*4882a593Smuzhiyun static int __must_check nr_add_node(ax25_address *nr, const char *mnemonic,
98*4882a593Smuzhiyun 	ax25_address *ax25, ax25_digi *ax25_digi, struct net_device *dev,
99*4882a593Smuzhiyun 	int quality, int obs_count)
100*4882a593Smuzhiyun {
101*4882a593Smuzhiyun 	struct nr_node  *nr_node;
102*4882a593Smuzhiyun 	struct nr_neigh *nr_neigh;
103*4882a593Smuzhiyun 	int i, found;
104*4882a593Smuzhiyun 	struct net_device *odev;
105*4882a593Smuzhiyun 
106*4882a593Smuzhiyun 	if ((odev=nr_dev_get(nr)) != NULL) {	/* Can't add routes to ourself */
107*4882a593Smuzhiyun 		dev_put(odev);
108*4882a593Smuzhiyun 		return -EINVAL;
109*4882a593Smuzhiyun 	}
110*4882a593Smuzhiyun 
111*4882a593Smuzhiyun 	nr_node = nr_node_get(nr);
112*4882a593Smuzhiyun 
113*4882a593Smuzhiyun 	nr_neigh = nr_neigh_get_dev(ax25, dev);
114*4882a593Smuzhiyun 
115*4882a593Smuzhiyun 	/*
116*4882a593Smuzhiyun 	 * The L2 link to a neighbour has failed in the past
117*4882a593Smuzhiyun 	 * and now a frame comes from this neighbour. We assume
118*4882a593Smuzhiyun 	 * it was a temporary trouble with the link and reset the
119*4882a593Smuzhiyun 	 * routes now (and not wait for a node broadcast).
120*4882a593Smuzhiyun 	 */
121*4882a593Smuzhiyun 	if (nr_neigh != NULL && nr_neigh->failed != 0 && quality == 0) {
122*4882a593Smuzhiyun 		struct nr_node *nr_nodet;
123*4882a593Smuzhiyun 
124*4882a593Smuzhiyun 		spin_lock_bh(&nr_node_list_lock);
125*4882a593Smuzhiyun 		nr_node_for_each(nr_nodet, &nr_node_list) {
126*4882a593Smuzhiyun 			nr_node_lock(nr_nodet);
127*4882a593Smuzhiyun 			for (i = 0; i < nr_nodet->count; i++)
128*4882a593Smuzhiyun 				if (nr_nodet->routes[i].neighbour == nr_neigh)
129*4882a593Smuzhiyun 					if (i < nr_nodet->which)
130*4882a593Smuzhiyun 						nr_nodet->which = i;
131*4882a593Smuzhiyun 			nr_node_unlock(nr_nodet);
132*4882a593Smuzhiyun 		}
133*4882a593Smuzhiyun 		spin_unlock_bh(&nr_node_list_lock);
134*4882a593Smuzhiyun 	}
135*4882a593Smuzhiyun 
136*4882a593Smuzhiyun 	if (nr_neigh != NULL)
137*4882a593Smuzhiyun 		nr_neigh->failed = 0;
138*4882a593Smuzhiyun 
139*4882a593Smuzhiyun 	if (quality == 0 && nr_neigh != NULL && nr_node != NULL) {
140*4882a593Smuzhiyun 		nr_neigh_put(nr_neigh);
141*4882a593Smuzhiyun 		nr_node_put(nr_node);
142*4882a593Smuzhiyun 		return 0;
143*4882a593Smuzhiyun 	}
144*4882a593Smuzhiyun 
145*4882a593Smuzhiyun 	if (nr_neigh == NULL) {
146*4882a593Smuzhiyun 		if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL) {
147*4882a593Smuzhiyun 			if (nr_node)
148*4882a593Smuzhiyun 				nr_node_put(nr_node);
149*4882a593Smuzhiyun 			return -ENOMEM;
150*4882a593Smuzhiyun 		}
151*4882a593Smuzhiyun 
152*4882a593Smuzhiyun 		nr_neigh->callsign = *ax25;
153*4882a593Smuzhiyun 		nr_neigh->digipeat = NULL;
154*4882a593Smuzhiyun 		nr_neigh->ax25     = NULL;
155*4882a593Smuzhiyun 		nr_neigh->dev      = dev;
156*4882a593Smuzhiyun 		nr_neigh->quality  = sysctl_netrom_default_path_quality;
157*4882a593Smuzhiyun 		nr_neigh->locked   = 0;
158*4882a593Smuzhiyun 		nr_neigh->count    = 0;
159*4882a593Smuzhiyun 		nr_neigh->number   = nr_neigh_no++;
160*4882a593Smuzhiyun 		nr_neigh->failed   = 0;
161*4882a593Smuzhiyun 		refcount_set(&nr_neigh->refcount, 1);
162*4882a593Smuzhiyun 
163*4882a593Smuzhiyun 		if (ax25_digi != NULL && ax25_digi->ndigi > 0) {
164*4882a593Smuzhiyun 			nr_neigh->digipeat = kmemdup(ax25_digi,
165*4882a593Smuzhiyun 						     sizeof(*ax25_digi),
166*4882a593Smuzhiyun 						     GFP_KERNEL);
167*4882a593Smuzhiyun 			if (nr_neigh->digipeat == NULL) {
168*4882a593Smuzhiyun 				kfree(nr_neigh);
169*4882a593Smuzhiyun 				if (nr_node)
170*4882a593Smuzhiyun 					nr_node_put(nr_node);
171*4882a593Smuzhiyun 				return -ENOMEM;
172*4882a593Smuzhiyun 			}
173*4882a593Smuzhiyun 		}
174*4882a593Smuzhiyun 
175*4882a593Smuzhiyun 		spin_lock_bh(&nr_neigh_list_lock);
176*4882a593Smuzhiyun 		hlist_add_head(&nr_neigh->neigh_node, &nr_neigh_list);
177*4882a593Smuzhiyun 		nr_neigh_hold(nr_neigh);
178*4882a593Smuzhiyun 		spin_unlock_bh(&nr_neigh_list_lock);
179*4882a593Smuzhiyun 	}
180*4882a593Smuzhiyun 
181*4882a593Smuzhiyun 	if (quality != 0 && ax25cmp(nr, ax25) == 0 && !nr_neigh->locked)
182*4882a593Smuzhiyun 		nr_neigh->quality = quality;
183*4882a593Smuzhiyun 
184*4882a593Smuzhiyun 	if (nr_node == NULL) {
185*4882a593Smuzhiyun 		if ((nr_node = kmalloc(sizeof(*nr_node), GFP_ATOMIC)) == NULL) {
186*4882a593Smuzhiyun 			if (nr_neigh)
187*4882a593Smuzhiyun 				nr_neigh_put(nr_neigh);
188*4882a593Smuzhiyun 			return -ENOMEM;
189*4882a593Smuzhiyun 		}
190*4882a593Smuzhiyun 
191*4882a593Smuzhiyun 		nr_node->callsign = *nr;
192*4882a593Smuzhiyun 		strcpy(nr_node->mnemonic, mnemonic);
193*4882a593Smuzhiyun 
194*4882a593Smuzhiyun 		nr_node->which = 0;
195*4882a593Smuzhiyun 		nr_node->count = 1;
196*4882a593Smuzhiyun 		refcount_set(&nr_node->refcount, 1);
197*4882a593Smuzhiyun 		spin_lock_init(&nr_node->node_lock);
198*4882a593Smuzhiyun 
199*4882a593Smuzhiyun 		nr_node->routes[0].quality   = quality;
200*4882a593Smuzhiyun 		nr_node->routes[0].obs_count = obs_count;
201*4882a593Smuzhiyun 		nr_node->routes[0].neighbour = nr_neigh;
202*4882a593Smuzhiyun 
203*4882a593Smuzhiyun 		nr_neigh_hold(nr_neigh);
204*4882a593Smuzhiyun 		nr_neigh->count++;
205*4882a593Smuzhiyun 
206*4882a593Smuzhiyun 		spin_lock_bh(&nr_node_list_lock);
207*4882a593Smuzhiyun 		hlist_add_head(&nr_node->node_node, &nr_node_list);
208*4882a593Smuzhiyun 		/* refcount initialized at 1 */
209*4882a593Smuzhiyun 		spin_unlock_bh(&nr_node_list_lock);
210*4882a593Smuzhiyun 
211*4882a593Smuzhiyun 		nr_neigh_put(nr_neigh);
212*4882a593Smuzhiyun 		return 0;
213*4882a593Smuzhiyun 	}
214*4882a593Smuzhiyun 	nr_node_lock(nr_node);
215*4882a593Smuzhiyun 
216*4882a593Smuzhiyun 	if (quality != 0)
217*4882a593Smuzhiyun 		strcpy(nr_node->mnemonic, mnemonic);
218*4882a593Smuzhiyun 
219*4882a593Smuzhiyun 	for (found = 0, i = 0; i < nr_node->count; i++) {
220*4882a593Smuzhiyun 		if (nr_node->routes[i].neighbour == nr_neigh) {
221*4882a593Smuzhiyun 			nr_node->routes[i].quality   = quality;
222*4882a593Smuzhiyun 			nr_node->routes[i].obs_count = obs_count;
223*4882a593Smuzhiyun 			found = 1;
224*4882a593Smuzhiyun 			break;
225*4882a593Smuzhiyun 		}
226*4882a593Smuzhiyun 	}
227*4882a593Smuzhiyun 
228*4882a593Smuzhiyun 	if (!found) {
229*4882a593Smuzhiyun 		/* We have space at the bottom, slot it in */
230*4882a593Smuzhiyun 		if (nr_node->count < 3) {
231*4882a593Smuzhiyun 			nr_node->routes[2] = nr_node->routes[1];
232*4882a593Smuzhiyun 			nr_node->routes[1] = nr_node->routes[0];
233*4882a593Smuzhiyun 
234*4882a593Smuzhiyun 			nr_node->routes[0].quality   = quality;
235*4882a593Smuzhiyun 			nr_node->routes[0].obs_count = obs_count;
236*4882a593Smuzhiyun 			nr_node->routes[0].neighbour = nr_neigh;
237*4882a593Smuzhiyun 
238*4882a593Smuzhiyun 			nr_node->which++;
239*4882a593Smuzhiyun 			nr_node->count++;
240*4882a593Smuzhiyun 			nr_neigh_hold(nr_neigh);
241*4882a593Smuzhiyun 			nr_neigh->count++;
242*4882a593Smuzhiyun 		} else {
243*4882a593Smuzhiyun 			/* It must be better than the worst */
244*4882a593Smuzhiyun 			if (quality > nr_node->routes[2].quality) {
245*4882a593Smuzhiyun 				nr_node->routes[2].neighbour->count--;
246*4882a593Smuzhiyun 				nr_neigh_put(nr_node->routes[2].neighbour);
247*4882a593Smuzhiyun 
248*4882a593Smuzhiyun 				if (nr_node->routes[2].neighbour->count == 0 && !nr_node->routes[2].neighbour->locked)
249*4882a593Smuzhiyun 					nr_remove_neigh(nr_node->routes[2].neighbour);
250*4882a593Smuzhiyun 
251*4882a593Smuzhiyun 				nr_node->routes[2].quality   = quality;
252*4882a593Smuzhiyun 				nr_node->routes[2].obs_count = obs_count;
253*4882a593Smuzhiyun 				nr_node->routes[2].neighbour = nr_neigh;
254*4882a593Smuzhiyun 
255*4882a593Smuzhiyun 				nr_neigh_hold(nr_neigh);
256*4882a593Smuzhiyun 				nr_neigh->count++;
257*4882a593Smuzhiyun 			}
258*4882a593Smuzhiyun 		}
259*4882a593Smuzhiyun 	}
260*4882a593Smuzhiyun 
261*4882a593Smuzhiyun 	/* Now re-sort the routes in quality order */
262*4882a593Smuzhiyun 	switch (nr_node->count) {
263*4882a593Smuzhiyun 	case 3:
264*4882a593Smuzhiyun 		re_sort_routes(nr_node, 0, 1);
265*4882a593Smuzhiyun 		re_sort_routes(nr_node, 1, 2);
266*4882a593Smuzhiyun 		fallthrough;
267*4882a593Smuzhiyun 	case 2:
268*4882a593Smuzhiyun 		re_sort_routes(nr_node, 0, 1);
269*4882a593Smuzhiyun 	case 1:
270*4882a593Smuzhiyun 		break;
271*4882a593Smuzhiyun 	}
272*4882a593Smuzhiyun 
273*4882a593Smuzhiyun 	for (i = 0; i < nr_node->count; i++) {
274*4882a593Smuzhiyun 		if (nr_node->routes[i].neighbour == nr_neigh) {
275*4882a593Smuzhiyun 			if (i < nr_node->which)
276*4882a593Smuzhiyun 				nr_node->which = i;
277*4882a593Smuzhiyun 			break;
278*4882a593Smuzhiyun 		}
279*4882a593Smuzhiyun 	}
280*4882a593Smuzhiyun 
281*4882a593Smuzhiyun 	nr_neigh_put(nr_neigh);
282*4882a593Smuzhiyun 	nr_node_unlock(nr_node);
283*4882a593Smuzhiyun 	nr_node_put(nr_node);
284*4882a593Smuzhiyun 	return 0;
285*4882a593Smuzhiyun }
286*4882a593Smuzhiyun 
__nr_remove_node(struct nr_node * nr_node)287*4882a593Smuzhiyun static inline void __nr_remove_node(struct nr_node *nr_node)
288*4882a593Smuzhiyun {
289*4882a593Smuzhiyun 	hlist_del_init(&nr_node->node_node);
290*4882a593Smuzhiyun 	nr_node_put(nr_node);
291*4882a593Smuzhiyun }
292*4882a593Smuzhiyun 
293*4882a593Smuzhiyun #define nr_remove_node_locked(__node) \
294*4882a593Smuzhiyun 	__nr_remove_node(__node)
295*4882a593Smuzhiyun 
nr_remove_node(struct nr_node * nr_node)296*4882a593Smuzhiyun static void nr_remove_node(struct nr_node *nr_node)
297*4882a593Smuzhiyun {
298*4882a593Smuzhiyun 	spin_lock_bh(&nr_node_list_lock);
299*4882a593Smuzhiyun 	__nr_remove_node(nr_node);
300*4882a593Smuzhiyun 	spin_unlock_bh(&nr_node_list_lock);
301*4882a593Smuzhiyun }
302*4882a593Smuzhiyun 
__nr_remove_neigh(struct nr_neigh * nr_neigh)303*4882a593Smuzhiyun static inline void __nr_remove_neigh(struct nr_neigh *nr_neigh)
304*4882a593Smuzhiyun {
305*4882a593Smuzhiyun 	hlist_del_init(&nr_neigh->neigh_node);
306*4882a593Smuzhiyun 	nr_neigh_put(nr_neigh);
307*4882a593Smuzhiyun }
308*4882a593Smuzhiyun 
309*4882a593Smuzhiyun #define nr_remove_neigh_locked(__neigh) \
310*4882a593Smuzhiyun 	__nr_remove_neigh(__neigh)
311*4882a593Smuzhiyun 
nr_remove_neigh(struct nr_neigh * nr_neigh)312*4882a593Smuzhiyun static void nr_remove_neigh(struct nr_neigh *nr_neigh)
313*4882a593Smuzhiyun {
314*4882a593Smuzhiyun 	spin_lock_bh(&nr_neigh_list_lock);
315*4882a593Smuzhiyun 	__nr_remove_neigh(nr_neigh);
316*4882a593Smuzhiyun 	spin_unlock_bh(&nr_neigh_list_lock);
317*4882a593Smuzhiyun }
318*4882a593Smuzhiyun 
319*4882a593Smuzhiyun /*
320*4882a593Smuzhiyun  *	"Delete" a node. Strictly speaking remove a route to a node. The node
321*4882a593Smuzhiyun  *	is only deleted if no routes are left to it.
322*4882a593Smuzhiyun  */
nr_del_node(ax25_address * callsign,ax25_address * neighbour,struct net_device * dev)323*4882a593Smuzhiyun static int nr_del_node(ax25_address *callsign, ax25_address *neighbour, struct net_device *dev)
324*4882a593Smuzhiyun {
325*4882a593Smuzhiyun 	struct nr_node  *nr_node;
326*4882a593Smuzhiyun 	struct nr_neigh *nr_neigh;
327*4882a593Smuzhiyun 	int i;
328*4882a593Smuzhiyun 
329*4882a593Smuzhiyun 	nr_node = nr_node_get(callsign);
330*4882a593Smuzhiyun 
331*4882a593Smuzhiyun 	if (nr_node == NULL)
332*4882a593Smuzhiyun 		return -EINVAL;
333*4882a593Smuzhiyun 
334*4882a593Smuzhiyun 	nr_neigh = nr_neigh_get_dev(neighbour, dev);
335*4882a593Smuzhiyun 
336*4882a593Smuzhiyun 	if (nr_neigh == NULL) {
337*4882a593Smuzhiyun 		nr_node_put(nr_node);
338*4882a593Smuzhiyun 		return -EINVAL;
339*4882a593Smuzhiyun 	}
340*4882a593Smuzhiyun 
341*4882a593Smuzhiyun 	nr_node_lock(nr_node);
342*4882a593Smuzhiyun 	for (i = 0; i < nr_node->count; i++) {
343*4882a593Smuzhiyun 		if (nr_node->routes[i].neighbour == nr_neigh) {
344*4882a593Smuzhiyun 			nr_neigh->count--;
345*4882a593Smuzhiyun 			nr_neigh_put(nr_neigh);
346*4882a593Smuzhiyun 
347*4882a593Smuzhiyun 			if (nr_neigh->count == 0 && !nr_neigh->locked)
348*4882a593Smuzhiyun 				nr_remove_neigh(nr_neigh);
349*4882a593Smuzhiyun 			nr_neigh_put(nr_neigh);
350*4882a593Smuzhiyun 
351*4882a593Smuzhiyun 			nr_node->count--;
352*4882a593Smuzhiyun 
353*4882a593Smuzhiyun 			if (nr_node->count == 0) {
354*4882a593Smuzhiyun 				nr_remove_node(nr_node);
355*4882a593Smuzhiyun 			} else {
356*4882a593Smuzhiyun 				switch (i) {
357*4882a593Smuzhiyun 				case 0:
358*4882a593Smuzhiyun 					nr_node->routes[0] = nr_node->routes[1];
359*4882a593Smuzhiyun 					fallthrough;
360*4882a593Smuzhiyun 				case 1:
361*4882a593Smuzhiyun 					nr_node->routes[1] = nr_node->routes[2];
362*4882a593Smuzhiyun 				case 2:
363*4882a593Smuzhiyun 					break;
364*4882a593Smuzhiyun 				}
365*4882a593Smuzhiyun 				nr_node_put(nr_node);
366*4882a593Smuzhiyun 			}
367*4882a593Smuzhiyun 			nr_node_unlock(nr_node);
368*4882a593Smuzhiyun 
369*4882a593Smuzhiyun 			return 0;
370*4882a593Smuzhiyun 		}
371*4882a593Smuzhiyun 	}
372*4882a593Smuzhiyun 	nr_neigh_put(nr_neigh);
373*4882a593Smuzhiyun 	nr_node_unlock(nr_node);
374*4882a593Smuzhiyun 	nr_node_put(nr_node);
375*4882a593Smuzhiyun 
376*4882a593Smuzhiyun 	return -EINVAL;
377*4882a593Smuzhiyun }
378*4882a593Smuzhiyun 
379*4882a593Smuzhiyun /*
380*4882a593Smuzhiyun  *	Lock a neighbour with a quality.
381*4882a593Smuzhiyun  */
nr_add_neigh(ax25_address * callsign,ax25_digi * ax25_digi,struct net_device * dev,unsigned int quality)382*4882a593Smuzhiyun static int __must_check nr_add_neigh(ax25_address *callsign,
383*4882a593Smuzhiyun 	ax25_digi *ax25_digi, struct net_device *dev, unsigned int quality)
384*4882a593Smuzhiyun {
385*4882a593Smuzhiyun 	struct nr_neigh *nr_neigh;
386*4882a593Smuzhiyun 
387*4882a593Smuzhiyun 	nr_neigh = nr_neigh_get_dev(callsign, dev);
388*4882a593Smuzhiyun 	if (nr_neigh) {
389*4882a593Smuzhiyun 		nr_neigh->quality = quality;
390*4882a593Smuzhiyun 		nr_neigh->locked  = 1;
391*4882a593Smuzhiyun 		nr_neigh_put(nr_neigh);
392*4882a593Smuzhiyun 		return 0;
393*4882a593Smuzhiyun 	}
394*4882a593Smuzhiyun 
395*4882a593Smuzhiyun 	if ((nr_neigh = kmalloc(sizeof(*nr_neigh), GFP_ATOMIC)) == NULL)
396*4882a593Smuzhiyun 		return -ENOMEM;
397*4882a593Smuzhiyun 
398*4882a593Smuzhiyun 	nr_neigh->callsign = *callsign;
399*4882a593Smuzhiyun 	nr_neigh->digipeat = NULL;
400*4882a593Smuzhiyun 	nr_neigh->ax25     = NULL;
401*4882a593Smuzhiyun 	nr_neigh->dev      = dev;
402*4882a593Smuzhiyun 	nr_neigh->quality  = quality;
403*4882a593Smuzhiyun 	nr_neigh->locked   = 1;
404*4882a593Smuzhiyun 	nr_neigh->count    = 0;
405*4882a593Smuzhiyun 	nr_neigh->number   = nr_neigh_no++;
406*4882a593Smuzhiyun 	nr_neigh->failed   = 0;
407*4882a593Smuzhiyun 	refcount_set(&nr_neigh->refcount, 1);
408*4882a593Smuzhiyun 
409*4882a593Smuzhiyun 	if (ax25_digi != NULL && ax25_digi->ndigi > 0) {
410*4882a593Smuzhiyun 		nr_neigh->digipeat = kmemdup(ax25_digi, sizeof(*ax25_digi),
411*4882a593Smuzhiyun 					     GFP_KERNEL);
412*4882a593Smuzhiyun 		if (nr_neigh->digipeat == NULL) {
413*4882a593Smuzhiyun 			kfree(nr_neigh);
414*4882a593Smuzhiyun 			return -ENOMEM;
415*4882a593Smuzhiyun 		}
416*4882a593Smuzhiyun 	}
417*4882a593Smuzhiyun 
418*4882a593Smuzhiyun 	spin_lock_bh(&nr_neigh_list_lock);
419*4882a593Smuzhiyun 	hlist_add_head(&nr_neigh->neigh_node, &nr_neigh_list);
420*4882a593Smuzhiyun 	/* refcount is initialized at 1 */
421*4882a593Smuzhiyun 	spin_unlock_bh(&nr_neigh_list_lock);
422*4882a593Smuzhiyun 
423*4882a593Smuzhiyun 	return 0;
424*4882a593Smuzhiyun }
425*4882a593Smuzhiyun 
426*4882a593Smuzhiyun /*
427*4882a593Smuzhiyun  *	"Delete" a neighbour. The neighbour is only removed if the number
428*4882a593Smuzhiyun  *	of nodes that may use it is zero.
429*4882a593Smuzhiyun  */
nr_del_neigh(ax25_address * callsign,struct net_device * dev,unsigned int quality)430*4882a593Smuzhiyun static int nr_del_neigh(ax25_address *callsign, struct net_device *dev, unsigned int quality)
431*4882a593Smuzhiyun {
432*4882a593Smuzhiyun 	struct nr_neigh *nr_neigh;
433*4882a593Smuzhiyun 
434*4882a593Smuzhiyun 	nr_neigh = nr_neigh_get_dev(callsign, dev);
435*4882a593Smuzhiyun 
436*4882a593Smuzhiyun 	if (nr_neigh == NULL) return -EINVAL;
437*4882a593Smuzhiyun 
438*4882a593Smuzhiyun 	nr_neigh->quality = quality;
439*4882a593Smuzhiyun 	nr_neigh->locked  = 0;
440*4882a593Smuzhiyun 
441*4882a593Smuzhiyun 	if (nr_neigh->count == 0)
442*4882a593Smuzhiyun 		nr_remove_neigh(nr_neigh);
443*4882a593Smuzhiyun 	nr_neigh_put(nr_neigh);
444*4882a593Smuzhiyun 
445*4882a593Smuzhiyun 	return 0;
446*4882a593Smuzhiyun }
447*4882a593Smuzhiyun 
448*4882a593Smuzhiyun /*
449*4882a593Smuzhiyun  *	Decrement the obsolescence count by one. If a route is reduced to a
450*4882a593Smuzhiyun  *	count of zero, remove it. Also remove any unlocked neighbours with
451*4882a593Smuzhiyun  *	zero nodes routing via it.
452*4882a593Smuzhiyun  */
nr_dec_obs(void)453*4882a593Smuzhiyun static int nr_dec_obs(void)
454*4882a593Smuzhiyun {
455*4882a593Smuzhiyun 	struct nr_neigh *nr_neigh;
456*4882a593Smuzhiyun 	struct nr_node  *s;
457*4882a593Smuzhiyun 	struct hlist_node *nodet;
458*4882a593Smuzhiyun 	int i;
459*4882a593Smuzhiyun 
460*4882a593Smuzhiyun 	spin_lock_bh(&nr_node_list_lock);
461*4882a593Smuzhiyun 	nr_node_for_each_safe(s, nodet, &nr_node_list) {
462*4882a593Smuzhiyun 		nr_node_lock(s);
463*4882a593Smuzhiyun 		for (i = 0; i < s->count; i++) {
464*4882a593Smuzhiyun 			switch (s->routes[i].obs_count) {
465*4882a593Smuzhiyun 			case 0:		/* A locked entry */
466*4882a593Smuzhiyun 				break;
467*4882a593Smuzhiyun 
468*4882a593Smuzhiyun 			case 1:		/* From 1 -> 0 */
469*4882a593Smuzhiyun 				nr_neigh = s->routes[i].neighbour;
470*4882a593Smuzhiyun 
471*4882a593Smuzhiyun 				nr_neigh->count--;
472*4882a593Smuzhiyun 				nr_neigh_put(nr_neigh);
473*4882a593Smuzhiyun 
474*4882a593Smuzhiyun 				if (nr_neigh->count == 0 && !nr_neigh->locked)
475*4882a593Smuzhiyun 					nr_remove_neigh(nr_neigh);
476*4882a593Smuzhiyun 
477*4882a593Smuzhiyun 				s->count--;
478*4882a593Smuzhiyun 
479*4882a593Smuzhiyun 				switch (i) {
480*4882a593Smuzhiyun 				case 0:
481*4882a593Smuzhiyun 					s->routes[0] = s->routes[1];
482*4882a593Smuzhiyun 					fallthrough;
483*4882a593Smuzhiyun 				case 1:
484*4882a593Smuzhiyun 					s->routes[1] = s->routes[2];
485*4882a593Smuzhiyun 				case 2:
486*4882a593Smuzhiyun 					break;
487*4882a593Smuzhiyun 				}
488*4882a593Smuzhiyun 				break;
489*4882a593Smuzhiyun 
490*4882a593Smuzhiyun 			default:
491*4882a593Smuzhiyun 				s->routes[i].obs_count--;
492*4882a593Smuzhiyun 				break;
493*4882a593Smuzhiyun 
494*4882a593Smuzhiyun 			}
495*4882a593Smuzhiyun 		}
496*4882a593Smuzhiyun 
497*4882a593Smuzhiyun 		if (s->count <= 0)
498*4882a593Smuzhiyun 			nr_remove_node_locked(s);
499*4882a593Smuzhiyun 		nr_node_unlock(s);
500*4882a593Smuzhiyun 	}
501*4882a593Smuzhiyun 	spin_unlock_bh(&nr_node_list_lock);
502*4882a593Smuzhiyun 
503*4882a593Smuzhiyun 	return 0;
504*4882a593Smuzhiyun }
505*4882a593Smuzhiyun 
506*4882a593Smuzhiyun /*
507*4882a593Smuzhiyun  *	A device has been removed. Remove its routes and neighbours.
508*4882a593Smuzhiyun  */
nr_rt_device_down(struct net_device * dev)509*4882a593Smuzhiyun void nr_rt_device_down(struct net_device *dev)
510*4882a593Smuzhiyun {
511*4882a593Smuzhiyun 	struct nr_neigh *s;
512*4882a593Smuzhiyun 	struct hlist_node *nodet, *node2t;
513*4882a593Smuzhiyun 	struct nr_node  *t;
514*4882a593Smuzhiyun 	int i;
515*4882a593Smuzhiyun 
516*4882a593Smuzhiyun 	spin_lock_bh(&nr_neigh_list_lock);
517*4882a593Smuzhiyun 	nr_neigh_for_each_safe(s, nodet, &nr_neigh_list) {
518*4882a593Smuzhiyun 		if (s->dev == dev) {
519*4882a593Smuzhiyun 			spin_lock_bh(&nr_node_list_lock);
520*4882a593Smuzhiyun 			nr_node_for_each_safe(t, node2t, &nr_node_list) {
521*4882a593Smuzhiyun 				nr_node_lock(t);
522*4882a593Smuzhiyun 				for (i = 0; i < t->count; i++) {
523*4882a593Smuzhiyun 					if (t->routes[i].neighbour == s) {
524*4882a593Smuzhiyun 						t->count--;
525*4882a593Smuzhiyun 
526*4882a593Smuzhiyun 						switch (i) {
527*4882a593Smuzhiyun 						case 0:
528*4882a593Smuzhiyun 							t->routes[0] = t->routes[1];
529*4882a593Smuzhiyun 							fallthrough;
530*4882a593Smuzhiyun 						case 1:
531*4882a593Smuzhiyun 							t->routes[1] = t->routes[2];
532*4882a593Smuzhiyun 						case 2:
533*4882a593Smuzhiyun 							break;
534*4882a593Smuzhiyun 						}
535*4882a593Smuzhiyun 					}
536*4882a593Smuzhiyun 				}
537*4882a593Smuzhiyun 
538*4882a593Smuzhiyun 				if (t->count <= 0)
539*4882a593Smuzhiyun 					nr_remove_node_locked(t);
540*4882a593Smuzhiyun 				nr_node_unlock(t);
541*4882a593Smuzhiyun 			}
542*4882a593Smuzhiyun 			spin_unlock_bh(&nr_node_list_lock);
543*4882a593Smuzhiyun 
544*4882a593Smuzhiyun 			nr_remove_neigh_locked(s);
545*4882a593Smuzhiyun 		}
546*4882a593Smuzhiyun 	}
547*4882a593Smuzhiyun 	spin_unlock_bh(&nr_neigh_list_lock);
548*4882a593Smuzhiyun }
549*4882a593Smuzhiyun 
550*4882a593Smuzhiyun /*
551*4882a593Smuzhiyun  *	Check that the device given is a valid AX.25 interface that is "up".
552*4882a593Smuzhiyun  *	Or a valid ethernet interface with an AX.25 callsign binding.
553*4882a593Smuzhiyun  */
nr_ax25_dev_get(char * devname)554*4882a593Smuzhiyun static struct net_device *nr_ax25_dev_get(char *devname)
555*4882a593Smuzhiyun {
556*4882a593Smuzhiyun 	struct net_device *dev;
557*4882a593Smuzhiyun 
558*4882a593Smuzhiyun 	if ((dev = dev_get_by_name(&init_net, devname)) == NULL)
559*4882a593Smuzhiyun 		return NULL;
560*4882a593Smuzhiyun 
561*4882a593Smuzhiyun 	if ((dev->flags & IFF_UP) && dev->type == ARPHRD_AX25)
562*4882a593Smuzhiyun 		return dev;
563*4882a593Smuzhiyun 
564*4882a593Smuzhiyun 	dev_put(dev);
565*4882a593Smuzhiyun 	return NULL;
566*4882a593Smuzhiyun }
567*4882a593Smuzhiyun 
568*4882a593Smuzhiyun /*
569*4882a593Smuzhiyun  *	Find the first active NET/ROM device, usually "nr0".
570*4882a593Smuzhiyun  */
nr_dev_first(void)571*4882a593Smuzhiyun struct net_device *nr_dev_first(void)
572*4882a593Smuzhiyun {
573*4882a593Smuzhiyun 	struct net_device *dev, *first = NULL;
574*4882a593Smuzhiyun 
575*4882a593Smuzhiyun 	rcu_read_lock();
576*4882a593Smuzhiyun 	for_each_netdev_rcu(&init_net, dev) {
577*4882a593Smuzhiyun 		if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM)
578*4882a593Smuzhiyun 			if (first == NULL || strncmp(dev->name, first->name, 3) < 0)
579*4882a593Smuzhiyun 				first = dev;
580*4882a593Smuzhiyun 	}
581*4882a593Smuzhiyun 	if (first)
582*4882a593Smuzhiyun 		dev_hold(first);
583*4882a593Smuzhiyun 	rcu_read_unlock();
584*4882a593Smuzhiyun 
585*4882a593Smuzhiyun 	return first;
586*4882a593Smuzhiyun }
587*4882a593Smuzhiyun 
588*4882a593Smuzhiyun /*
589*4882a593Smuzhiyun  *	Find the NET/ROM device for the given callsign.
590*4882a593Smuzhiyun  */
nr_dev_get(ax25_address * addr)591*4882a593Smuzhiyun struct net_device *nr_dev_get(ax25_address *addr)
592*4882a593Smuzhiyun {
593*4882a593Smuzhiyun 	struct net_device *dev;
594*4882a593Smuzhiyun 
595*4882a593Smuzhiyun 	rcu_read_lock();
596*4882a593Smuzhiyun 	for_each_netdev_rcu(&init_net, dev) {
597*4882a593Smuzhiyun 		if ((dev->flags & IFF_UP) && dev->type == ARPHRD_NETROM &&
598*4882a593Smuzhiyun 		    ax25cmp(addr, (ax25_address *)dev->dev_addr) == 0) {
599*4882a593Smuzhiyun 			dev_hold(dev);
600*4882a593Smuzhiyun 			goto out;
601*4882a593Smuzhiyun 		}
602*4882a593Smuzhiyun 	}
603*4882a593Smuzhiyun 	dev = NULL;
604*4882a593Smuzhiyun out:
605*4882a593Smuzhiyun 	rcu_read_unlock();
606*4882a593Smuzhiyun 	return dev;
607*4882a593Smuzhiyun }
608*4882a593Smuzhiyun 
nr_call_to_digi(ax25_digi * digi,int ndigis,ax25_address * digipeaters)609*4882a593Smuzhiyun static ax25_digi *nr_call_to_digi(ax25_digi *digi, int ndigis,
610*4882a593Smuzhiyun 	ax25_address *digipeaters)
611*4882a593Smuzhiyun {
612*4882a593Smuzhiyun 	int i;
613*4882a593Smuzhiyun 
614*4882a593Smuzhiyun 	if (ndigis == 0)
615*4882a593Smuzhiyun 		return NULL;
616*4882a593Smuzhiyun 
617*4882a593Smuzhiyun 	for (i = 0; i < ndigis; i++) {
618*4882a593Smuzhiyun 		digi->calls[i]    = digipeaters[i];
619*4882a593Smuzhiyun 		digi->repeated[i] = 0;
620*4882a593Smuzhiyun 	}
621*4882a593Smuzhiyun 
622*4882a593Smuzhiyun 	digi->ndigi      = ndigis;
623*4882a593Smuzhiyun 	digi->lastrepeat = -1;
624*4882a593Smuzhiyun 
625*4882a593Smuzhiyun 	return digi;
626*4882a593Smuzhiyun }
627*4882a593Smuzhiyun 
628*4882a593Smuzhiyun /*
629*4882a593Smuzhiyun  *	Handle the ioctls that control the routing functions.
630*4882a593Smuzhiyun  */
nr_rt_ioctl(unsigned int cmd,void __user * arg)631*4882a593Smuzhiyun int nr_rt_ioctl(unsigned int cmd, void __user *arg)
632*4882a593Smuzhiyun {
633*4882a593Smuzhiyun 	struct nr_route_struct nr_route;
634*4882a593Smuzhiyun 	struct net_device *dev;
635*4882a593Smuzhiyun 	ax25_digi digi;
636*4882a593Smuzhiyun 	int ret;
637*4882a593Smuzhiyun 
638*4882a593Smuzhiyun 	switch (cmd) {
639*4882a593Smuzhiyun 	case SIOCADDRT:
640*4882a593Smuzhiyun 		if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct)))
641*4882a593Smuzhiyun 			return -EFAULT;
642*4882a593Smuzhiyun 		if (nr_route.ndigis > AX25_MAX_DIGIS)
643*4882a593Smuzhiyun 			return -EINVAL;
644*4882a593Smuzhiyun 		if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL)
645*4882a593Smuzhiyun 			return -EINVAL;
646*4882a593Smuzhiyun 		switch (nr_route.type) {
647*4882a593Smuzhiyun 		case NETROM_NODE:
648*4882a593Smuzhiyun 			if (strnlen(nr_route.mnemonic, 7) == 7) {
649*4882a593Smuzhiyun 				ret = -EINVAL;
650*4882a593Smuzhiyun 				break;
651*4882a593Smuzhiyun 			}
652*4882a593Smuzhiyun 
653*4882a593Smuzhiyun 			ret = nr_add_node(&nr_route.callsign,
654*4882a593Smuzhiyun 				nr_route.mnemonic,
655*4882a593Smuzhiyun 				&nr_route.neighbour,
656*4882a593Smuzhiyun 				nr_call_to_digi(&digi, nr_route.ndigis,
657*4882a593Smuzhiyun 						nr_route.digipeaters),
658*4882a593Smuzhiyun 				dev, nr_route.quality,
659*4882a593Smuzhiyun 				nr_route.obs_count);
660*4882a593Smuzhiyun 			break;
661*4882a593Smuzhiyun 		case NETROM_NEIGH:
662*4882a593Smuzhiyun 			ret = nr_add_neigh(&nr_route.callsign,
663*4882a593Smuzhiyun 				nr_call_to_digi(&digi, nr_route.ndigis,
664*4882a593Smuzhiyun 						nr_route.digipeaters),
665*4882a593Smuzhiyun 				dev, nr_route.quality);
666*4882a593Smuzhiyun 			break;
667*4882a593Smuzhiyun 		default:
668*4882a593Smuzhiyun 			ret = -EINVAL;
669*4882a593Smuzhiyun 		}
670*4882a593Smuzhiyun 		dev_put(dev);
671*4882a593Smuzhiyun 		return ret;
672*4882a593Smuzhiyun 
673*4882a593Smuzhiyun 	case SIOCDELRT:
674*4882a593Smuzhiyun 		if (copy_from_user(&nr_route, arg, sizeof(struct nr_route_struct)))
675*4882a593Smuzhiyun 			return -EFAULT;
676*4882a593Smuzhiyun 		if ((dev = nr_ax25_dev_get(nr_route.device)) == NULL)
677*4882a593Smuzhiyun 			return -EINVAL;
678*4882a593Smuzhiyun 		switch (nr_route.type) {
679*4882a593Smuzhiyun 		case NETROM_NODE:
680*4882a593Smuzhiyun 			ret = nr_del_node(&nr_route.callsign,
681*4882a593Smuzhiyun 				&nr_route.neighbour, dev);
682*4882a593Smuzhiyun 			break;
683*4882a593Smuzhiyun 		case NETROM_NEIGH:
684*4882a593Smuzhiyun 			ret = nr_del_neigh(&nr_route.callsign,
685*4882a593Smuzhiyun 				dev, nr_route.quality);
686*4882a593Smuzhiyun 			break;
687*4882a593Smuzhiyun 		default:
688*4882a593Smuzhiyun 			ret = -EINVAL;
689*4882a593Smuzhiyun 		}
690*4882a593Smuzhiyun 		dev_put(dev);
691*4882a593Smuzhiyun 		return ret;
692*4882a593Smuzhiyun 
693*4882a593Smuzhiyun 	case SIOCNRDECOBS:
694*4882a593Smuzhiyun 		return nr_dec_obs();
695*4882a593Smuzhiyun 
696*4882a593Smuzhiyun 	default:
697*4882a593Smuzhiyun 		return -EINVAL;
698*4882a593Smuzhiyun 	}
699*4882a593Smuzhiyun 
700*4882a593Smuzhiyun 	return 0;
701*4882a593Smuzhiyun }
702*4882a593Smuzhiyun 
703*4882a593Smuzhiyun /*
704*4882a593Smuzhiyun  * 	A level 2 link has timed out, therefore it appears to be a poor link,
705*4882a593Smuzhiyun  *	then don't use that neighbour until it is reset.
706*4882a593Smuzhiyun  */
nr_link_failed(ax25_cb * ax25,int reason)707*4882a593Smuzhiyun void nr_link_failed(ax25_cb *ax25, int reason)
708*4882a593Smuzhiyun {
709*4882a593Smuzhiyun 	struct nr_neigh *s, *nr_neigh = NULL;
710*4882a593Smuzhiyun 	struct nr_node  *nr_node = NULL;
711*4882a593Smuzhiyun 
712*4882a593Smuzhiyun 	spin_lock_bh(&nr_neigh_list_lock);
713*4882a593Smuzhiyun 	nr_neigh_for_each(s, &nr_neigh_list) {
714*4882a593Smuzhiyun 		if (s->ax25 == ax25) {
715*4882a593Smuzhiyun 			nr_neigh_hold(s);
716*4882a593Smuzhiyun 			nr_neigh = s;
717*4882a593Smuzhiyun 			break;
718*4882a593Smuzhiyun 		}
719*4882a593Smuzhiyun 	}
720*4882a593Smuzhiyun 	spin_unlock_bh(&nr_neigh_list_lock);
721*4882a593Smuzhiyun 
722*4882a593Smuzhiyun 	if (nr_neigh == NULL)
723*4882a593Smuzhiyun 		return;
724*4882a593Smuzhiyun 
725*4882a593Smuzhiyun 	nr_neigh->ax25 = NULL;
726*4882a593Smuzhiyun 	ax25_cb_put(ax25);
727*4882a593Smuzhiyun 
728*4882a593Smuzhiyun 	if (++nr_neigh->failed < sysctl_netrom_link_fails_count) {
729*4882a593Smuzhiyun 		nr_neigh_put(nr_neigh);
730*4882a593Smuzhiyun 		return;
731*4882a593Smuzhiyun 	}
732*4882a593Smuzhiyun 	spin_lock_bh(&nr_node_list_lock);
733*4882a593Smuzhiyun 	nr_node_for_each(nr_node, &nr_node_list) {
734*4882a593Smuzhiyun 		nr_node_lock(nr_node);
735*4882a593Smuzhiyun 		if (nr_node->which < nr_node->count &&
736*4882a593Smuzhiyun 		    nr_node->routes[nr_node->which].neighbour == nr_neigh)
737*4882a593Smuzhiyun 			nr_node->which++;
738*4882a593Smuzhiyun 		nr_node_unlock(nr_node);
739*4882a593Smuzhiyun 	}
740*4882a593Smuzhiyun 	spin_unlock_bh(&nr_node_list_lock);
741*4882a593Smuzhiyun 	nr_neigh_put(nr_neigh);
742*4882a593Smuzhiyun }
743*4882a593Smuzhiyun 
744*4882a593Smuzhiyun /*
745*4882a593Smuzhiyun  *	Route a frame to an appropriate AX.25 connection. A NULL ax25_cb
746*4882a593Smuzhiyun  *	indicates an internally generated frame.
747*4882a593Smuzhiyun  */
nr_route_frame(struct sk_buff * skb,ax25_cb * ax25)748*4882a593Smuzhiyun int nr_route_frame(struct sk_buff *skb, ax25_cb *ax25)
749*4882a593Smuzhiyun {
750*4882a593Smuzhiyun 	ax25_address *nr_src, *nr_dest;
751*4882a593Smuzhiyun 	struct nr_neigh *nr_neigh;
752*4882a593Smuzhiyun 	struct nr_node  *nr_node;
753*4882a593Smuzhiyun 	struct net_device *dev;
754*4882a593Smuzhiyun 	unsigned char *dptr;
755*4882a593Smuzhiyun 	ax25_cb *ax25s;
756*4882a593Smuzhiyun 	int ret;
757*4882a593Smuzhiyun 	struct sk_buff *skbn;
758*4882a593Smuzhiyun 
759*4882a593Smuzhiyun 
760*4882a593Smuzhiyun 	nr_src  = (ax25_address *)(skb->data + 0);
761*4882a593Smuzhiyun 	nr_dest = (ax25_address *)(skb->data + 7);
762*4882a593Smuzhiyun 
763*4882a593Smuzhiyun 	if (ax25 != NULL) {
764*4882a593Smuzhiyun 		ret = nr_add_node(nr_src, "", &ax25->dest_addr, ax25->digipeat,
765*4882a593Smuzhiyun 				  ax25->ax25_dev->dev, 0,
766*4882a593Smuzhiyun 				  sysctl_netrom_obsolescence_count_initialiser);
767*4882a593Smuzhiyun 		if (ret)
768*4882a593Smuzhiyun 			return ret;
769*4882a593Smuzhiyun 	}
770*4882a593Smuzhiyun 
771*4882a593Smuzhiyun 	if ((dev = nr_dev_get(nr_dest)) != NULL) {	/* Its for me */
772*4882a593Smuzhiyun 		if (ax25 == NULL)			/* Its from me */
773*4882a593Smuzhiyun 			ret = nr_loopback_queue(skb);
774*4882a593Smuzhiyun 		else
775*4882a593Smuzhiyun 			ret = nr_rx_frame(skb, dev);
776*4882a593Smuzhiyun 		dev_put(dev);
777*4882a593Smuzhiyun 		return ret;
778*4882a593Smuzhiyun 	}
779*4882a593Smuzhiyun 
780*4882a593Smuzhiyun 	if (!sysctl_netrom_routing_control && ax25 != NULL)
781*4882a593Smuzhiyun 		return 0;
782*4882a593Smuzhiyun 
783*4882a593Smuzhiyun 	/* Its Time-To-Live has expired */
784*4882a593Smuzhiyun 	if (skb->data[14] == 1) {
785*4882a593Smuzhiyun 		return 0;
786*4882a593Smuzhiyun 	}
787*4882a593Smuzhiyun 
788*4882a593Smuzhiyun 	nr_node = nr_node_get(nr_dest);
789*4882a593Smuzhiyun 	if (nr_node == NULL)
790*4882a593Smuzhiyun 		return 0;
791*4882a593Smuzhiyun 	nr_node_lock(nr_node);
792*4882a593Smuzhiyun 
793*4882a593Smuzhiyun 	if (nr_node->which >= nr_node->count) {
794*4882a593Smuzhiyun 		nr_node_unlock(nr_node);
795*4882a593Smuzhiyun 		nr_node_put(nr_node);
796*4882a593Smuzhiyun 		return 0;
797*4882a593Smuzhiyun 	}
798*4882a593Smuzhiyun 
799*4882a593Smuzhiyun 	nr_neigh = nr_node->routes[nr_node->which].neighbour;
800*4882a593Smuzhiyun 
801*4882a593Smuzhiyun 	if ((dev = nr_dev_first()) == NULL) {
802*4882a593Smuzhiyun 		nr_node_unlock(nr_node);
803*4882a593Smuzhiyun 		nr_node_put(nr_node);
804*4882a593Smuzhiyun 		return 0;
805*4882a593Smuzhiyun 	}
806*4882a593Smuzhiyun 
807*4882a593Smuzhiyun 	/* We are going to change the netrom headers so we should get our
808*4882a593Smuzhiyun 	   own skb, we also did not know until now how much header space
809*4882a593Smuzhiyun 	   we had to reserve... - RXQ */
810*4882a593Smuzhiyun 	if ((skbn=skb_copy_expand(skb, dev->hard_header_len, 0, GFP_ATOMIC)) == NULL) {
811*4882a593Smuzhiyun 		nr_node_unlock(nr_node);
812*4882a593Smuzhiyun 		nr_node_put(nr_node);
813*4882a593Smuzhiyun 		dev_put(dev);
814*4882a593Smuzhiyun 		return 0;
815*4882a593Smuzhiyun 	}
816*4882a593Smuzhiyun 	kfree_skb(skb);
817*4882a593Smuzhiyun 	skb=skbn;
818*4882a593Smuzhiyun 	skb->data[14]--;
819*4882a593Smuzhiyun 
820*4882a593Smuzhiyun 	dptr  = skb_push(skb, 1);
821*4882a593Smuzhiyun 	*dptr = AX25_P_NETROM;
822*4882a593Smuzhiyun 
823*4882a593Smuzhiyun 	ax25s = nr_neigh->ax25;
824*4882a593Smuzhiyun 	nr_neigh->ax25 = ax25_send_frame(skb, 256,
825*4882a593Smuzhiyun 					 (ax25_address *)dev->dev_addr,
826*4882a593Smuzhiyun 					 &nr_neigh->callsign,
827*4882a593Smuzhiyun 					 nr_neigh->digipeat, nr_neigh->dev);
828*4882a593Smuzhiyun 	if (ax25s)
829*4882a593Smuzhiyun 		ax25_cb_put(ax25s);
830*4882a593Smuzhiyun 
831*4882a593Smuzhiyun 	dev_put(dev);
832*4882a593Smuzhiyun 	ret = (nr_neigh->ax25 != NULL);
833*4882a593Smuzhiyun 	nr_node_unlock(nr_node);
834*4882a593Smuzhiyun 	nr_node_put(nr_node);
835*4882a593Smuzhiyun 
836*4882a593Smuzhiyun 	return ret;
837*4882a593Smuzhiyun }
838*4882a593Smuzhiyun 
839*4882a593Smuzhiyun #ifdef CONFIG_PROC_FS
840*4882a593Smuzhiyun 
nr_node_start(struct seq_file * seq,loff_t * pos)841*4882a593Smuzhiyun static void *nr_node_start(struct seq_file *seq, loff_t *pos)
842*4882a593Smuzhiyun 	__acquires(&nr_node_list_lock)
843*4882a593Smuzhiyun {
844*4882a593Smuzhiyun 	spin_lock_bh(&nr_node_list_lock);
845*4882a593Smuzhiyun 	return seq_hlist_start_head(&nr_node_list, *pos);
846*4882a593Smuzhiyun }
847*4882a593Smuzhiyun 
nr_node_next(struct seq_file * seq,void * v,loff_t * pos)848*4882a593Smuzhiyun static void *nr_node_next(struct seq_file *seq, void *v, loff_t *pos)
849*4882a593Smuzhiyun {
850*4882a593Smuzhiyun 	return seq_hlist_next(v, &nr_node_list, pos);
851*4882a593Smuzhiyun }
852*4882a593Smuzhiyun 
nr_node_stop(struct seq_file * seq,void * v)853*4882a593Smuzhiyun static void nr_node_stop(struct seq_file *seq, void *v)
854*4882a593Smuzhiyun 	__releases(&nr_node_list_lock)
855*4882a593Smuzhiyun {
856*4882a593Smuzhiyun 	spin_unlock_bh(&nr_node_list_lock);
857*4882a593Smuzhiyun }
858*4882a593Smuzhiyun 
nr_node_show(struct seq_file * seq,void * v)859*4882a593Smuzhiyun static int nr_node_show(struct seq_file *seq, void *v)
860*4882a593Smuzhiyun {
861*4882a593Smuzhiyun 	char buf[11];
862*4882a593Smuzhiyun 	int i;
863*4882a593Smuzhiyun 
864*4882a593Smuzhiyun 	if (v == SEQ_START_TOKEN)
865*4882a593Smuzhiyun 		seq_puts(seq,
866*4882a593Smuzhiyun 			 "callsign  mnemonic w n qual obs neigh qual obs neigh qual obs neigh\n");
867*4882a593Smuzhiyun 	else {
868*4882a593Smuzhiyun 		struct nr_node *nr_node = hlist_entry(v, struct nr_node,
869*4882a593Smuzhiyun 						      node_node);
870*4882a593Smuzhiyun 
871*4882a593Smuzhiyun 		nr_node_lock(nr_node);
872*4882a593Smuzhiyun 		seq_printf(seq, "%-9s %-7s  %d %d",
873*4882a593Smuzhiyun 			ax2asc(buf, &nr_node->callsign),
874*4882a593Smuzhiyun 			(nr_node->mnemonic[0] == '\0') ? "*" : nr_node->mnemonic,
875*4882a593Smuzhiyun 			nr_node->which + 1,
876*4882a593Smuzhiyun 			nr_node->count);
877*4882a593Smuzhiyun 
878*4882a593Smuzhiyun 		for (i = 0; i < nr_node->count; i++) {
879*4882a593Smuzhiyun 			seq_printf(seq, "  %3d   %d %05d",
880*4882a593Smuzhiyun 				nr_node->routes[i].quality,
881*4882a593Smuzhiyun 				nr_node->routes[i].obs_count,
882*4882a593Smuzhiyun 				nr_node->routes[i].neighbour->number);
883*4882a593Smuzhiyun 		}
884*4882a593Smuzhiyun 		nr_node_unlock(nr_node);
885*4882a593Smuzhiyun 
886*4882a593Smuzhiyun 		seq_puts(seq, "\n");
887*4882a593Smuzhiyun 	}
888*4882a593Smuzhiyun 	return 0;
889*4882a593Smuzhiyun }
890*4882a593Smuzhiyun 
891*4882a593Smuzhiyun const struct seq_operations nr_node_seqops = {
892*4882a593Smuzhiyun 	.start = nr_node_start,
893*4882a593Smuzhiyun 	.next = nr_node_next,
894*4882a593Smuzhiyun 	.stop = nr_node_stop,
895*4882a593Smuzhiyun 	.show = nr_node_show,
896*4882a593Smuzhiyun };
897*4882a593Smuzhiyun 
nr_neigh_start(struct seq_file * seq,loff_t * pos)898*4882a593Smuzhiyun static void *nr_neigh_start(struct seq_file *seq, loff_t *pos)
899*4882a593Smuzhiyun 	__acquires(&nr_neigh_list_lock)
900*4882a593Smuzhiyun {
901*4882a593Smuzhiyun 	spin_lock_bh(&nr_neigh_list_lock);
902*4882a593Smuzhiyun 	return seq_hlist_start_head(&nr_neigh_list, *pos);
903*4882a593Smuzhiyun }
904*4882a593Smuzhiyun 
nr_neigh_next(struct seq_file * seq,void * v,loff_t * pos)905*4882a593Smuzhiyun static void *nr_neigh_next(struct seq_file *seq, void *v, loff_t *pos)
906*4882a593Smuzhiyun {
907*4882a593Smuzhiyun 	return seq_hlist_next(v, &nr_neigh_list, pos);
908*4882a593Smuzhiyun }
909*4882a593Smuzhiyun 
nr_neigh_stop(struct seq_file * seq,void * v)910*4882a593Smuzhiyun static void nr_neigh_stop(struct seq_file *seq, void *v)
911*4882a593Smuzhiyun 	__releases(&nr_neigh_list_lock)
912*4882a593Smuzhiyun {
913*4882a593Smuzhiyun 	spin_unlock_bh(&nr_neigh_list_lock);
914*4882a593Smuzhiyun }
915*4882a593Smuzhiyun 
nr_neigh_show(struct seq_file * seq,void * v)916*4882a593Smuzhiyun static int nr_neigh_show(struct seq_file *seq, void *v)
917*4882a593Smuzhiyun {
918*4882a593Smuzhiyun 	char buf[11];
919*4882a593Smuzhiyun 	int i;
920*4882a593Smuzhiyun 
921*4882a593Smuzhiyun 	if (v == SEQ_START_TOKEN)
922*4882a593Smuzhiyun 		seq_puts(seq, "addr  callsign  dev  qual lock count failed digipeaters\n");
923*4882a593Smuzhiyun 	else {
924*4882a593Smuzhiyun 		struct nr_neigh *nr_neigh;
925*4882a593Smuzhiyun 
926*4882a593Smuzhiyun 		nr_neigh = hlist_entry(v, struct nr_neigh, neigh_node);
927*4882a593Smuzhiyun 		seq_printf(seq, "%05d %-9s %-4s  %3d    %d   %3d    %3d",
928*4882a593Smuzhiyun 			nr_neigh->number,
929*4882a593Smuzhiyun 			ax2asc(buf, &nr_neigh->callsign),
930*4882a593Smuzhiyun 			nr_neigh->dev ? nr_neigh->dev->name : "???",
931*4882a593Smuzhiyun 			nr_neigh->quality,
932*4882a593Smuzhiyun 			nr_neigh->locked,
933*4882a593Smuzhiyun 			nr_neigh->count,
934*4882a593Smuzhiyun 			nr_neigh->failed);
935*4882a593Smuzhiyun 
936*4882a593Smuzhiyun 		if (nr_neigh->digipeat != NULL) {
937*4882a593Smuzhiyun 			for (i = 0; i < nr_neigh->digipeat->ndigi; i++)
938*4882a593Smuzhiyun 				seq_printf(seq, " %s",
939*4882a593Smuzhiyun 					   ax2asc(buf, &nr_neigh->digipeat->calls[i]));
940*4882a593Smuzhiyun 		}
941*4882a593Smuzhiyun 
942*4882a593Smuzhiyun 		seq_puts(seq, "\n");
943*4882a593Smuzhiyun 	}
944*4882a593Smuzhiyun 	return 0;
945*4882a593Smuzhiyun }
946*4882a593Smuzhiyun 
947*4882a593Smuzhiyun const struct seq_operations nr_neigh_seqops = {
948*4882a593Smuzhiyun 	.start = nr_neigh_start,
949*4882a593Smuzhiyun 	.next = nr_neigh_next,
950*4882a593Smuzhiyun 	.stop = nr_neigh_stop,
951*4882a593Smuzhiyun 	.show = nr_neigh_show,
952*4882a593Smuzhiyun };
953*4882a593Smuzhiyun #endif
954*4882a593Smuzhiyun 
955*4882a593Smuzhiyun /*
956*4882a593Smuzhiyun  *	Free all memory associated with the nodes and routes lists.
957*4882a593Smuzhiyun  */
nr_rt_free(void)958*4882a593Smuzhiyun void nr_rt_free(void)
959*4882a593Smuzhiyun {
960*4882a593Smuzhiyun 	struct nr_neigh *s = NULL;
961*4882a593Smuzhiyun 	struct nr_node  *t = NULL;
962*4882a593Smuzhiyun 	struct hlist_node *nodet;
963*4882a593Smuzhiyun 
964*4882a593Smuzhiyun 	spin_lock_bh(&nr_neigh_list_lock);
965*4882a593Smuzhiyun 	spin_lock_bh(&nr_node_list_lock);
966*4882a593Smuzhiyun 	nr_node_for_each_safe(t, nodet, &nr_node_list) {
967*4882a593Smuzhiyun 		nr_node_lock(t);
968*4882a593Smuzhiyun 		nr_remove_node_locked(t);
969*4882a593Smuzhiyun 		nr_node_unlock(t);
970*4882a593Smuzhiyun 	}
971*4882a593Smuzhiyun 	nr_neigh_for_each_safe(s, nodet, &nr_neigh_list) {
972*4882a593Smuzhiyun 		while(s->count) {
973*4882a593Smuzhiyun 			s->count--;
974*4882a593Smuzhiyun 			nr_neigh_put(s);
975*4882a593Smuzhiyun 		}
976*4882a593Smuzhiyun 		nr_remove_neigh_locked(s);
977*4882a593Smuzhiyun 	}
978*4882a593Smuzhiyun 	spin_unlock_bh(&nr_node_list_lock);
979*4882a593Smuzhiyun 	spin_unlock_bh(&nr_neigh_list_lock);
980*4882a593Smuzhiyun }
981