xref: /linux/net/netrom/af_netrom.c (revision da5b2ad1c2f18834cb1ce429e2e5a5cf5cbdf21b)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *
4  * Copyright Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk)
5  * Copyright Alan Cox GW4PTS (alan@lxorguk.ukuu.org.uk)
6  * Copyright Darryl Miles G7LED (dlm@g7led.demon.co.uk)
7  */
8 #include <linux/module.h>
9 #include <linux/moduleparam.h>
10 #include <linux/capability.h>
11 #include <linux/errno.h>
12 #include <linux/types.h>
13 #include <linux/socket.h>
14 #include <linux/in.h>
15 #include <linux/slab.h>
16 #include <linux/kernel.h>
17 #include <linux/sched/signal.h>
18 #include <linux/timer.h>
19 #include <linux/string.h>
20 #include <linux/sockios.h>
21 #include <linux/net.h>
22 #include <linux/stat.h>
23 #include <net/ax25.h>
24 #include <linux/inet.h>
25 #include <linux/netdevice.h>
26 #include <linux/if_arp.h>
27 #include <linux/skbuff.h>
28 #include <net/net_namespace.h>
29 #include <net/sock.h>
30 #include <linux/uaccess.h>
31 #include <linux/fcntl.h>
32 #include <linux/termios.h>	/* For TIOCINQ/OUTQ */
33 #include <linux/mm.h>
34 #include <linux/interrupt.h>
35 #include <linux/notifier.h>
36 #include <net/netrom.h>
37 #include <linux/proc_fs.h>
38 #include <linux/seq_file.h>
39 #include <net/ip.h>
40 #include <net/tcp_states.h>
41 #include <net/arp.h>
42 #include <linux/init.h>
43 
44 static int nr_ndevs = 4;
45 
46 int sysctl_netrom_default_path_quality            = NR_DEFAULT_QUAL;
47 int sysctl_netrom_obsolescence_count_initialiser  = NR_DEFAULT_OBS;
48 int sysctl_netrom_network_ttl_initialiser         = NR_DEFAULT_TTL;
49 int sysctl_netrom_transport_timeout               = NR_DEFAULT_T1;
50 int sysctl_netrom_transport_maximum_tries         = NR_DEFAULT_N2;
51 int sysctl_netrom_transport_acknowledge_delay     = NR_DEFAULT_T2;
52 int sysctl_netrom_transport_busy_delay            = NR_DEFAULT_T4;
53 int sysctl_netrom_transport_requested_window_size = NR_DEFAULT_WINDOW;
54 int sysctl_netrom_transport_no_activity_timeout   = NR_DEFAULT_IDLE;
55 int sysctl_netrom_routing_control                 = NR_DEFAULT_ROUTING;
56 int sysctl_netrom_link_fails_count                = NR_DEFAULT_FAILS;
57 int sysctl_netrom_reset_circuit                   = NR_DEFAULT_RESET;
58 
59 static unsigned short circuit = 0x101;
60 
61 static HLIST_HEAD(nr_list);
62 static DEFINE_SPINLOCK(nr_list_lock);
63 
64 static const struct proto_ops nr_proto_ops;
65 
66 /*
67  * NETROM network devices are virtual network devices encapsulating NETROM
68  * frames into AX.25 which will be sent through an AX.25 device, so form a
69  * special "super class" of normal net devices; split their locks off into a
70  * separate class since they always nest.
71  */
72 static struct lock_class_key nr_netdev_xmit_lock_key;
73 static struct lock_class_key nr_netdev_addr_lock_key;
74 
75 static void nr_set_lockdep_one(struct net_device *dev,
76 			       struct netdev_queue *txq,
77 			       void *_unused)
78 {
79 	lockdep_set_class(&txq->_xmit_lock, &nr_netdev_xmit_lock_key);
80 }
81 
82 static void nr_set_lockdep_key(struct net_device *dev)
83 {
84 	lockdep_set_class(&dev->addr_list_lock, &nr_netdev_addr_lock_key);
85 	netdev_for_each_tx_queue(dev, nr_set_lockdep_one, NULL);
86 }
87 
88 /*
89  *	Socket removal during an interrupt is now safe.
90  */
91 static void nr_remove_socket(struct sock *sk)
92 {
93 	spin_lock_bh(&nr_list_lock);
94 	sk_del_node_init(sk);
95 	spin_unlock_bh(&nr_list_lock);
96 }
97 
98 /*
99  *	Kill all bound sockets on a dropped device.
100  */
101 static void nr_kill_by_device(struct net_device *dev)
102 {
103 	struct sock *s;
104 
105 	spin_lock_bh(&nr_list_lock);
106 	sk_for_each(s, &nr_list)
107 		if (nr_sk(s)->device == dev)
108 			nr_disconnect(s, ENETUNREACH);
109 	spin_unlock_bh(&nr_list_lock);
110 }
111 
112 /*
113  *	Handle device status changes.
114  */
115 static int nr_device_event(struct notifier_block *this, unsigned long event, void *ptr)
116 {
117 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
118 
119 	if (!net_eq(dev_net(dev), &init_net))
120 		return NOTIFY_DONE;
121 
122 	if (event != NETDEV_DOWN)
123 		return NOTIFY_DONE;
124 
125 	nr_kill_by_device(dev);
126 	nr_rt_device_down(dev);
127 
128 	return NOTIFY_DONE;
129 }
130 
131 /*
132  *	Add a socket to the bound sockets list.
133  */
134 static void nr_insert_socket(struct sock *sk)
135 {
136 	spin_lock_bh(&nr_list_lock);
137 	sk_add_node(sk, &nr_list);
138 	spin_unlock_bh(&nr_list_lock);
139 }
140 
141 /*
142  *	Find a socket that wants to accept the Connect Request we just
143  *	received.
144  */
145 static struct sock *nr_find_listener(ax25_address *addr)
146 {
147 	struct sock *s;
148 
149 	spin_lock_bh(&nr_list_lock);
150 	sk_for_each(s, &nr_list)
151 		if (!ax25cmp(&nr_sk(s)->source_addr, addr) &&
152 		    s->sk_state == TCP_LISTEN) {
153 			sock_hold(s);
154 			goto found;
155 		}
156 	s = NULL;
157 found:
158 	spin_unlock_bh(&nr_list_lock);
159 	return s;
160 }
161 
162 /*
163  *	Find a connected NET/ROM socket given my circuit IDs.
164  */
165 static struct sock *nr_find_socket(unsigned char index, unsigned char id)
166 {
167 	struct sock *s;
168 
169 	spin_lock_bh(&nr_list_lock);
170 	sk_for_each(s, &nr_list) {
171 		struct nr_sock *nr = nr_sk(s);
172 
173 		if (nr->my_index == index && nr->my_id == id) {
174 			sock_hold(s);
175 			goto found;
176 		}
177 	}
178 	s = NULL;
179 found:
180 	spin_unlock_bh(&nr_list_lock);
181 	return s;
182 }
183 
184 /*
185  *	Find a connected NET/ROM socket given their circuit IDs.
186  */
187 static struct sock *nr_find_peer(unsigned char index, unsigned char id,
188 	ax25_address *dest)
189 {
190 	struct sock *s;
191 
192 	spin_lock_bh(&nr_list_lock);
193 	sk_for_each(s, &nr_list) {
194 		struct nr_sock *nr = nr_sk(s);
195 
196 		if (nr->your_index == index && nr->your_id == id &&
197 		    !ax25cmp(&nr->dest_addr, dest)) {
198 			sock_hold(s);
199 			goto found;
200 		}
201 	}
202 	s = NULL;
203 found:
204 	spin_unlock_bh(&nr_list_lock);
205 	return s;
206 }
207 
208 /*
209  *	Find next free circuit ID.
210  */
211 static unsigned short nr_find_next_circuit(void)
212 {
213 	unsigned short id = circuit;
214 	unsigned char i, j;
215 	struct sock *sk;
216 
217 	for (;;) {
218 		i = id / 256;
219 		j = id % 256;
220 
221 		if (i != 0 && j != 0) {
222 			if ((sk=nr_find_socket(i, j)) == NULL)
223 				break;
224 			sock_put(sk);
225 		}
226 
227 		id++;
228 	}
229 
230 	return id;
231 }
232 
233 /*
234  *	Deferred destroy.
235  */
236 void nr_destroy_socket(struct sock *);
237 
238 /*
239  *	Handler for deferred kills.
240  */
241 static void nr_destroy_timer(struct timer_list *t)
242 {
243 	struct sock *sk = from_timer(sk, t, sk_timer);
244 	bh_lock_sock(sk);
245 	sock_hold(sk);
246 	nr_destroy_socket(sk);
247 	bh_unlock_sock(sk);
248 	sock_put(sk);
249 }
250 
251 /*
252  *	This is called from user mode and the timers. Thus it protects itself
253  *	against interrupt users but doesn't worry about being called during
254  *	work. Once it is removed from the queue no interrupt or bottom half
255  *	will touch it and we are (fairly 8-) ) safe.
256  */
257 void nr_destroy_socket(struct sock *sk)
258 {
259 	struct sk_buff *skb;
260 
261 	nr_remove_socket(sk);
262 
263 	nr_stop_heartbeat(sk);
264 	nr_stop_t1timer(sk);
265 	nr_stop_t2timer(sk);
266 	nr_stop_t4timer(sk);
267 	nr_stop_idletimer(sk);
268 
269 	nr_clear_queues(sk);		/* Flush the queues */
270 
271 	while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
272 		if (skb->sk != sk) { /* A pending connection */
273 			/* Queue the unaccepted socket for death */
274 			sock_set_flag(skb->sk, SOCK_DEAD);
275 			nr_start_heartbeat(skb->sk);
276 			nr_sk(skb->sk)->state = NR_STATE_0;
277 		}
278 
279 		kfree_skb(skb);
280 	}
281 
282 	if (sk_has_allocations(sk)) {
283 		/* Defer: outstanding buffers */
284 		sk->sk_timer.function = nr_destroy_timer;
285 		sk->sk_timer.expires  = jiffies + 2 * HZ;
286 		add_timer(&sk->sk_timer);
287 	} else
288 		sock_put(sk);
289 }
290 
291 /*
292  *	Handling for system calls applied via the various interfaces to a
293  *	NET/ROM socket object.
294  */
295 
296 static int nr_setsockopt(struct socket *sock, int level, int optname,
297 		sockptr_t optval, unsigned int optlen)
298 {
299 	struct sock *sk = sock->sk;
300 	struct nr_sock *nr = nr_sk(sk);
301 	unsigned int opt;
302 
303 	if (level != SOL_NETROM)
304 		return -ENOPROTOOPT;
305 
306 	if (optlen < sizeof(unsigned int))
307 		return -EINVAL;
308 
309 	if (copy_from_sockptr(&opt, optval, sizeof(opt)))
310 		return -EFAULT;
311 
312 	switch (optname) {
313 	case NETROM_T1:
314 		if (opt < 1 || opt > UINT_MAX / HZ)
315 			return -EINVAL;
316 		nr->t1 = opt * HZ;
317 		return 0;
318 
319 	case NETROM_T2:
320 		if (opt < 1 || opt > UINT_MAX / HZ)
321 			return -EINVAL;
322 		nr->t2 = opt * HZ;
323 		return 0;
324 
325 	case NETROM_N2:
326 		if (opt < 1 || opt > 31)
327 			return -EINVAL;
328 		nr->n2 = opt;
329 		return 0;
330 
331 	case NETROM_T4:
332 		if (opt < 1 || opt > UINT_MAX / HZ)
333 			return -EINVAL;
334 		nr->t4 = opt * HZ;
335 		return 0;
336 
337 	case NETROM_IDLE:
338 		if (opt > UINT_MAX / (60 * HZ))
339 			return -EINVAL;
340 		nr->idle = opt * 60 * HZ;
341 		return 0;
342 
343 	default:
344 		return -ENOPROTOOPT;
345 	}
346 }
347 
348 static int nr_getsockopt(struct socket *sock, int level, int optname,
349 	char __user *optval, int __user *optlen)
350 {
351 	struct sock *sk = sock->sk;
352 	struct nr_sock *nr = nr_sk(sk);
353 	int val = 0;
354 	int len;
355 
356 	if (level != SOL_NETROM)
357 		return -ENOPROTOOPT;
358 
359 	if (get_user(len, optlen))
360 		return -EFAULT;
361 
362 	if (len < 0)
363 		return -EINVAL;
364 
365 	switch (optname) {
366 	case NETROM_T1:
367 		val = nr->t1 / HZ;
368 		break;
369 
370 	case NETROM_T2:
371 		val = nr->t2 / HZ;
372 		break;
373 
374 	case NETROM_N2:
375 		val = nr->n2;
376 		break;
377 
378 	case NETROM_T4:
379 		val = nr->t4 / HZ;
380 		break;
381 
382 	case NETROM_IDLE:
383 		val = nr->idle / (60 * HZ);
384 		break;
385 
386 	default:
387 		return -ENOPROTOOPT;
388 	}
389 
390 	len = min_t(unsigned int, len, sizeof(int));
391 
392 	if (put_user(len, optlen))
393 		return -EFAULT;
394 
395 	return copy_to_user(optval, &val, len) ? -EFAULT : 0;
396 }
397 
398 static int nr_listen(struct socket *sock, int backlog)
399 {
400 	struct sock *sk = sock->sk;
401 
402 	lock_sock(sk);
403 	if (sock->state != SS_UNCONNECTED) {
404 		release_sock(sk);
405 		return -EINVAL;
406 	}
407 
408 	if (sk->sk_state != TCP_LISTEN) {
409 		memset(&nr_sk(sk)->user_addr, 0, AX25_ADDR_LEN);
410 		sk->sk_max_ack_backlog = backlog;
411 		sk->sk_state           = TCP_LISTEN;
412 		release_sock(sk);
413 		return 0;
414 	}
415 	release_sock(sk);
416 
417 	return -EOPNOTSUPP;
418 }
419 
420 static struct proto nr_proto = {
421 	.name	  = "NETROM",
422 	.owner	  = THIS_MODULE,
423 	.obj_size = sizeof(struct nr_sock),
424 };
425 
426 static int nr_create(struct net *net, struct socket *sock, int protocol,
427 		     int kern)
428 {
429 	struct sock *sk;
430 	struct nr_sock *nr;
431 
432 	if (!net_eq(net, &init_net))
433 		return -EAFNOSUPPORT;
434 
435 	if (sock->type != SOCK_SEQPACKET || protocol != 0)
436 		return -ESOCKTNOSUPPORT;
437 
438 	sk = sk_alloc(net, PF_NETROM, GFP_ATOMIC, &nr_proto, kern);
439 	if (sk  == NULL)
440 		return -ENOMEM;
441 
442 	nr = nr_sk(sk);
443 
444 	sock_init_data(sock, sk);
445 
446 	sock->ops    = &nr_proto_ops;
447 	sk->sk_protocol = protocol;
448 
449 	skb_queue_head_init(&nr->ack_queue);
450 	skb_queue_head_init(&nr->reseq_queue);
451 	skb_queue_head_init(&nr->frag_queue);
452 
453 	nr_init_timers(sk);
454 
455 	nr->t1     =
456 		msecs_to_jiffies(READ_ONCE(sysctl_netrom_transport_timeout));
457 	nr->t2     =
458 		msecs_to_jiffies(READ_ONCE(sysctl_netrom_transport_acknowledge_delay));
459 	nr->n2     =
460 		msecs_to_jiffies(READ_ONCE(sysctl_netrom_transport_maximum_tries));
461 	nr->t4     =
462 		msecs_to_jiffies(READ_ONCE(sysctl_netrom_transport_busy_delay));
463 	nr->idle   =
464 		msecs_to_jiffies(READ_ONCE(sysctl_netrom_transport_no_activity_timeout));
465 	nr->window = READ_ONCE(sysctl_netrom_transport_requested_window_size);
466 
467 	nr->bpqext = 1;
468 	nr->state  = NR_STATE_0;
469 
470 	return 0;
471 }
472 
473 static struct sock *nr_make_new(struct sock *osk)
474 {
475 	struct sock *sk;
476 	struct nr_sock *nr, *onr;
477 
478 	if (osk->sk_type != SOCK_SEQPACKET)
479 		return NULL;
480 
481 	sk = sk_alloc(sock_net(osk), PF_NETROM, GFP_ATOMIC, osk->sk_prot, 0);
482 	if (sk == NULL)
483 		return NULL;
484 
485 	nr = nr_sk(sk);
486 
487 	sock_init_data(NULL, sk);
488 
489 	sk->sk_type     = osk->sk_type;
490 	sk->sk_priority = READ_ONCE(osk->sk_priority);
491 	sk->sk_protocol = osk->sk_protocol;
492 	sk->sk_rcvbuf   = osk->sk_rcvbuf;
493 	sk->sk_sndbuf   = osk->sk_sndbuf;
494 	sk->sk_state    = TCP_ESTABLISHED;
495 	sock_copy_flags(sk, osk);
496 
497 	skb_queue_head_init(&nr->ack_queue);
498 	skb_queue_head_init(&nr->reseq_queue);
499 	skb_queue_head_init(&nr->frag_queue);
500 
501 	nr_init_timers(sk);
502 
503 	onr = nr_sk(osk);
504 
505 	nr->t1      = onr->t1;
506 	nr->t2      = onr->t2;
507 	nr->n2      = onr->n2;
508 	nr->t4      = onr->t4;
509 	nr->idle    = onr->idle;
510 	nr->window  = onr->window;
511 
512 	nr->device  = onr->device;
513 	nr->bpqext  = onr->bpqext;
514 
515 	return sk;
516 }
517 
518 static int nr_release(struct socket *sock)
519 {
520 	struct sock *sk = sock->sk;
521 	struct nr_sock *nr;
522 
523 	if (sk == NULL) return 0;
524 
525 	sock_hold(sk);
526 	sock_orphan(sk);
527 	lock_sock(sk);
528 	nr = nr_sk(sk);
529 
530 	switch (nr->state) {
531 	case NR_STATE_0:
532 	case NR_STATE_1:
533 	case NR_STATE_2:
534 		nr_disconnect(sk, 0);
535 		nr_destroy_socket(sk);
536 		break;
537 
538 	case NR_STATE_3:
539 		nr_clear_queues(sk);
540 		nr->n2count = 0;
541 		nr_write_internal(sk, NR_DISCREQ);
542 		nr_start_t1timer(sk);
543 		nr_stop_t2timer(sk);
544 		nr_stop_t4timer(sk);
545 		nr_stop_idletimer(sk);
546 		nr->state    = NR_STATE_2;
547 		sk->sk_state    = TCP_CLOSE;
548 		sk->sk_shutdown |= SEND_SHUTDOWN;
549 		sk->sk_state_change(sk);
550 		sock_set_flag(sk, SOCK_DESTROY);
551 		break;
552 
553 	default:
554 		break;
555 	}
556 
557 	sock->sk   = NULL;
558 	release_sock(sk);
559 	sock_put(sk);
560 
561 	return 0;
562 }
563 
564 static int nr_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
565 {
566 	struct sock *sk = sock->sk;
567 	struct nr_sock *nr = nr_sk(sk);
568 	struct full_sockaddr_ax25 *addr = (struct full_sockaddr_ax25 *)uaddr;
569 	struct net_device *dev;
570 	ax25_uid_assoc *user;
571 	ax25_address *source;
572 
573 	lock_sock(sk);
574 	if (!sock_flag(sk, SOCK_ZAPPED)) {
575 		release_sock(sk);
576 		return -EINVAL;
577 	}
578 	if (addr_len < sizeof(struct sockaddr_ax25) || addr_len > sizeof(struct full_sockaddr_ax25)) {
579 		release_sock(sk);
580 		return -EINVAL;
581 	}
582 	if (addr_len < (addr->fsa_ax25.sax25_ndigis * sizeof(ax25_address) + sizeof(struct sockaddr_ax25))) {
583 		release_sock(sk);
584 		return -EINVAL;
585 	}
586 	if (addr->fsa_ax25.sax25_family != AF_NETROM) {
587 		release_sock(sk);
588 		return -EINVAL;
589 	}
590 	if ((dev = nr_dev_get(&addr->fsa_ax25.sax25_call)) == NULL) {
591 		release_sock(sk);
592 		return -EADDRNOTAVAIL;
593 	}
594 
595 	/*
596 	 * Only the super user can set an arbitrary user callsign.
597 	 */
598 	if (addr->fsa_ax25.sax25_ndigis == 1) {
599 		if (!capable(CAP_NET_BIND_SERVICE)) {
600 			dev_put(dev);
601 			release_sock(sk);
602 			return -EPERM;
603 		}
604 		nr->user_addr   = addr->fsa_digipeater[0];
605 		nr->source_addr = addr->fsa_ax25.sax25_call;
606 	} else {
607 		source = &addr->fsa_ax25.sax25_call;
608 
609 		user = ax25_findbyuid(current_euid());
610 		if (user) {
611 			nr->user_addr   = user->call;
612 			ax25_uid_put(user);
613 		} else {
614 			if (ax25_uid_policy && !capable(CAP_NET_BIND_SERVICE)) {
615 				release_sock(sk);
616 				dev_put(dev);
617 				return -EPERM;
618 			}
619 			nr->user_addr   = *source;
620 		}
621 
622 		nr->source_addr = *source;
623 	}
624 
625 	nr->device = dev;
626 	nr_insert_socket(sk);
627 
628 	sock_reset_flag(sk, SOCK_ZAPPED);
629 	dev_put(dev);
630 	release_sock(sk);
631 
632 	return 0;
633 }
634 
635 static int nr_connect(struct socket *sock, struct sockaddr *uaddr,
636 	int addr_len, int flags)
637 {
638 	struct sock *sk = sock->sk;
639 	struct nr_sock *nr = nr_sk(sk);
640 	struct sockaddr_ax25 *addr = (struct sockaddr_ax25 *)uaddr;
641 	const ax25_address *source = NULL;
642 	ax25_uid_assoc *user;
643 	struct net_device *dev;
644 	int err = 0;
645 
646 	lock_sock(sk);
647 	if (sk->sk_state == TCP_ESTABLISHED && sock->state == SS_CONNECTING) {
648 		sock->state = SS_CONNECTED;
649 		goto out_release;	/* Connect completed during a ERESTARTSYS event */
650 	}
651 
652 	if (sk->sk_state == TCP_CLOSE && sock->state == SS_CONNECTING) {
653 		sock->state = SS_UNCONNECTED;
654 		err = -ECONNREFUSED;
655 		goto out_release;
656 	}
657 
658 	if (sk->sk_state == TCP_ESTABLISHED) {
659 		err = -EISCONN;	/* No reconnect on a seqpacket socket */
660 		goto out_release;
661 	}
662 
663 	if (sock->state == SS_CONNECTING) {
664 		err = -EALREADY;
665 		goto out_release;
666 	}
667 
668 	sk->sk_state   = TCP_CLOSE;
669 	sock->state = SS_UNCONNECTED;
670 
671 	if (addr_len != sizeof(struct sockaddr_ax25) && addr_len != sizeof(struct full_sockaddr_ax25)) {
672 		err = -EINVAL;
673 		goto out_release;
674 	}
675 	if (addr->sax25_family != AF_NETROM) {
676 		err = -EINVAL;
677 		goto out_release;
678 	}
679 	if (sock_flag(sk, SOCK_ZAPPED)) {	/* Must bind first - autobinding in this may or may not work */
680 		sock_reset_flag(sk, SOCK_ZAPPED);
681 
682 		if ((dev = nr_dev_first()) == NULL) {
683 			err = -ENETUNREACH;
684 			goto out_release;
685 		}
686 		source = (const ax25_address *)dev->dev_addr;
687 
688 		user = ax25_findbyuid(current_euid());
689 		if (user) {
690 			nr->user_addr   = user->call;
691 			ax25_uid_put(user);
692 		} else {
693 			if (ax25_uid_policy && !capable(CAP_NET_ADMIN)) {
694 				dev_put(dev);
695 				err = -EPERM;
696 				goto out_release;
697 			}
698 			nr->user_addr   = *source;
699 		}
700 
701 		nr->source_addr = *source;
702 		nr->device      = dev;
703 
704 		dev_put(dev);
705 		nr_insert_socket(sk);		/* Finish the bind */
706 	}
707 
708 	nr->dest_addr = addr->sax25_call;
709 
710 	release_sock(sk);
711 	circuit = nr_find_next_circuit();
712 	lock_sock(sk);
713 
714 	nr->my_index = circuit / 256;
715 	nr->my_id    = circuit % 256;
716 
717 	circuit++;
718 
719 	/* Move to connecting socket, start sending Connect Requests */
720 	sock->state  = SS_CONNECTING;
721 	sk->sk_state = TCP_SYN_SENT;
722 
723 	nr_establish_data_link(sk);
724 
725 	nr->state = NR_STATE_1;
726 
727 	nr_start_heartbeat(sk);
728 
729 	/* Now the loop */
730 	if (sk->sk_state != TCP_ESTABLISHED && (flags & O_NONBLOCK)) {
731 		err = -EINPROGRESS;
732 		goto out_release;
733 	}
734 
735 	/*
736 	 * A Connect Ack with Choke or timeout or failed routing will go to
737 	 * closed.
738 	 */
739 	if (sk->sk_state == TCP_SYN_SENT) {
740 		DEFINE_WAIT(wait);
741 
742 		for (;;) {
743 			prepare_to_wait(sk_sleep(sk), &wait,
744 					TASK_INTERRUPTIBLE);
745 			if (sk->sk_state != TCP_SYN_SENT)
746 				break;
747 			if (!signal_pending(current)) {
748 				release_sock(sk);
749 				schedule();
750 				lock_sock(sk);
751 				continue;
752 			}
753 			err = -ERESTARTSYS;
754 			break;
755 		}
756 		finish_wait(sk_sleep(sk), &wait);
757 		if (err)
758 			goto out_release;
759 	}
760 
761 	if (sk->sk_state != TCP_ESTABLISHED) {
762 		sock->state = SS_UNCONNECTED;
763 		err = sock_error(sk);	/* Always set at this point */
764 		goto out_release;
765 	}
766 
767 	sock->state = SS_CONNECTED;
768 
769 out_release:
770 	release_sock(sk);
771 
772 	return err;
773 }
774 
775 static int nr_accept(struct socket *sock, struct socket *newsock,
776 		     struct proto_accept_arg *arg)
777 {
778 	struct sk_buff *skb;
779 	struct sock *newsk;
780 	DEFINE_WAIT(wait);
781 	struct sock *sk;
782 	int err = 0;
783 
784 	if ((sk = sock->sk) == NULL)
785 		return -EINVAL;
786 
787 	lock_sock(sk);
788 	if (sk->sk_type != SOCK_SEQPACKET) {
789 		err = -EOPNOTSUPP;
790 		goto out_release;
791 	}
792 
793 	if (sk->sk_state != TCP_LISTEN) {
794 		err = -EINVAL;
795 		goto out_release;
796 	}
797 
798 	/*
799 	 *	The write queue this time is holding sockets ready to use
800 	 *	hooked into the SABM we saved
801 	 */
802 	for (;;) {
803 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
804 		skb = skb_dequeue(&sk->sk_receive_queue);
805 		if (skb)
806 			break;
807 
808 		if (arg->flags & O_NONBLOCK) {
809 			err = -EWOULDBLOCK;
810 			break;
811 		}
812 		if (!signal_pending(current)) {
813 			release_sock(sk);
814 			schedule();
815 			lock_sock(sk);
816 			continue;
817 		}
818 		err = -ERESTARTSYS;
819 		break;
820 	}
821 	finish_wait(sk_sleep(sk), &wait);
822 	if (err)
823 		goto out_release;
824 
825 	newsk = skb->sk;
826 	sock_graft(newsk, newsock);
827 
828 	/* Now attach up the new socket */
829 	kfree_skb(skb);
830 	sk_acceptq_removed(sk);
831 
832 out_release:
833 	release_sock(sk);
834 
835 	return err;
836 }
837 
838 static int nr_getname(struct socket *sock, struct sockaddr *uaddr,
839 	int peer)
840 {
841 	struct full_sockaddr_ax25 *sax = (struct full_sockaddr_ax25 *)uaddr;
842 	struct sock *sk = sock->sk;
843 	struct nr_sock *nr = nr_sk(sk);
844 	int uaddr_len;
845 
846 	memset(&sax->fsa_ax25, 0, sizeof(struct sockaddr_ax25));
847 
848 	lock_sock(sk);
849 	if (peer != 0) {
850 		if (sk->sk_state != TCP_ESTABLISHED) {
851 			release_sock(sk);
852 			return -ENOTCONN;
853 		}
854 		sax->fsa_ax25.sax25_family = AF_NETROM;
855 		sax->fsa_ax25.sax25_ndigis = 1;
856 		sax->fsa_ax25.sax25_call   = nr->user_addr;
857 		memset(sax->fsa_digipeater, 0, sizeof(sax->fsa_digipeater));
858 		sax->fsa_digipeater[0]     = nr->dest_addr;
859 		uaddr_len = sizeof(struct full_sockaddr_ax25);
860 	} else {
861 		sax->fsa_ax25.sax25_family = AF_NETROM;
862 		sax->fsa_ax25.sax25_ndigis = 0;
863 		sax->fsa_ax25.sax25_call   = nr->source_addr;
864 		uaddr_len = sizeof(struct sockaddr_ax25);
865 	}
866 	release_sock(sk);
867 
868 	return uaddr_len;
869 }
870 
871 int nr_rx_frame(struct sk_buff *skb, struct net_device *dev)
872 {
873 	struct sock *sk;
874 	struct sock *make;
875 	struct nr_sock *nr_make;
876 	ax25_address *src, *dest, *user;
877 	unsigned short circuit_index, circuit_id;
878 	unsigned short peer_circuit_index, peer_circuit_id;
879 	unsigned short frametype, flags, window, timeout;
880 	int ret;
881 
882 	skb_orphan(skb);
883 
884 	/*
885 	 *	skb->data points to the netrom frame start
886 	 */
887 
888 	src  = (ax25_address *)(skb->data + 0);
889 	dest = (ax25_address *)(skb->data + 7);
890 
891 	circuit_index      = skb->data[15];
892 	circuit_id         = skb->data[16];
893 	peer_circuit_index = skb->data[17];
894 	peer_circuit_id    = skb->data[18];
895 	frametype          = skb->data[19] & 0x0F;
896 	flags              = skb->data[19] & 0xF0;
897 
898 	/*
899 	 * Check for an incoming IP over NET/ROM frame.
900 	 */
901 	if (frametype == NR_PROTOEXT &&
902 	    circuit_index == NR_PROTO_IP && circuit_id == NR_PROTO_IP) {
903 		skb_pull(skb, NR_NETWORK_LEN + NR_TRANSPORT_LEN);
904 		skb_reset_transport_header(skb);
905 
906 		return nr_rx_ip(skb, dev);
907 	}
908 
909 	/*
910 	 * Find an existing socket connection, based on circuit ID, if it's
911 	 * a Connect Request base it on their circuit ID.
912 	 *
913 	 * Circuit ID 0/0 is not valid but it could still be a "reset" for a
914 	 * circuit that no longer exists at the other end ...
915 	 */
916 
917 	sk = NULL;
918 
919 	if (circuit_index == 0 && circuit_id == 0) {
920 		if (frametype == NR_CONNACK && flags == NR_CHOKE_FLAG)
921 			sk = nr_find_peer(peer_circuit_index, peer_circuit_id, src);
922 	} else {
923 		if (frametype == NR_CONNREQ)
924 			sk = nr_find_peer(circuit_index, circuit_id, src);
925 		else
926 			sk = nr_find_socket(circuit_index, circuit_id);
927 	}
928 
929 	if (sk != NULL) {
930 		bh_lock_sock(sk);
931 		skb_reset_transport_header(skb);
932 
933 		if (frametype == NR_CONNACK && skb->len == 22)
934 			nr_sk(sk)->bpqext = 1;
935 		else
936 			nr_sk(sk)->bpqext = 0;
937 
938 		ret = nr_process_rx_frame(sk, skb);
939 		bh_unlock_sock(sk);
940 		sock_put(sk);
941 		return ret;
942 	}
943 
944 	/*
945 	 * Now it should be a CONNREQ.
946 	 */
947 	if (frametype != NR_CONNREQ) {
948 		/*
949 		 * Here it would be nice to be able to send a reset but
950 		 * NET/ROM doesn't have one.  We've tried to extend the protocol
951 		 * by sending NR_CONNACK | NR_CHOKE_FLAGS replies but that
952 		 * apparently kills BPQ boxes... :-(
953 		 * So now we try to follow the established behaviour of
954 		 * G8PZT's Xrouter which is sending packets with command type 7
955 		 * as an extension of the protocol.
956 		 */
957 		if (READ_ONCE(sysctl_netrom_reset_circuit) &&
958 		    (frametype != NR_RESET || flags != 0))
959 			nr_transmit_reset(skb, 1);
960 
961 		return 0;
962 	}
963 
964 	sk = nr_find_listener(dest);
965 
966 	user = (ax25_address *)(skb->data + 21);
967 
968 	if (sk == NULL || sk_acceptq_is_full(sk) ||
969 	    (make = nr_make_new(sk)) == NULL) {
970 		nr_transmit_refusal(skb, 0);
971 		if (sk)
972 			sock_put(sk);
973 		return 0;
974 	}
975 
976 	bh_lock_sock(sk);
977 
978 	window = skb->data[20];
979 
980 	sock_hold(make);
981 	skb->sk             = make;
982 	skb->destructor     = sock_efree;
983 	make->sk_state	    = TCP_ESTABLISHED;
984 
985 	/* Fill in his circuit details */
986 	nr_make = nr_sk(make);
987 	nr_make->source_addr = *dest;
988 	nr_make->dest_addr   = *src;
989 	nr_make->user_addr   = *user;
990 
991 	nr_make->your_index  = circuit_index;
992 	nr_make->your_id     = circuit_id;
993 
994 	bh_unlock_sock(sk);
995 	circuit = nr_find_next_circuit();
996 	bh_lock_sock(sk);
997 
998 	nr_make->my_index    = circuit / 256;
999 	nr_make->my_id       = circuit % 256;
1000 
1001 	circuit++;
1002 
1003 	/* Window negotiation */
1004 	if (window < nr_make->window)
1005 		nr_make->window = window;
1006 
1007 	/* L4 timeout negotiation */
1008 	if (skb->len == 37) {
1009 		timeout = skb->data[36] * 256 + skb->data[35];
1010 		if (timeout * HZ < nr_make->t1)
1011 			nr_make->t1 = timeout * HZ;
1012 		nr_make->bpqext = 1;
1013 	} else {
1014 		nr_make->bpqext = 0;
1015 	}
1016 
1017 	nr_write_internal(make, NR_CONNACK);
1018 
1019 	nr_make->condition = 0x00;
1020 	nr_make->vs        = 0;
1021 	nr_make->va        = 0;
1022 	nr_make->vr        = 0;
1023 	nr_make->vl        = 0;
1024 	nr_make->state     = NR_STATE_3;
1025 	sk_acceptq_added(sk);
1026 	skb_queue_head(&sk->sk_receive_queue, skb);
1027 
1028 	if (!sock_flag(sk, SOCK_DEAD))
1029 		sk->sk_data_ready(sk);
1030 
1031 	bh_unlock_sock(sk);
1032 	sock_put(sk);
1033 
1034 	nr_insert_socket(make);
1035 
1036 	nr_start_heartbeat(make);
1037 	nr_start_idletimer(make);
1038 
1039 	return 1;
1040 }
1041 
1042 static int nr_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
1043 {
1044 	struct sock *sk = sock->sk;
1045 	struct nr_sock *nr = nr_sk(sk);
1046 	DECLARE_SOCKADDR(struct sockaddr_ax25 *, usax, msg->msg_name);
1047 	int err;
1048 	struct sockaddr_ax25 sax;
1049 	struct sk_buff *skb;
1050 	unsigned char *asmptr;
1051 	int size;
1052 
1053 	if (msg->msg_flags & ~(MSG_DONTWAIT|MSG_EOR|MSG_CMSG_COMPAT))
1054 		return -EINVAL;
1055 
1056 	lock_sock(sk);
1057 	if (sock_flag(sk, SOCK_ZAPPED)) {
1058 		err = -EADDRNOTAVAIL;
1059 		goto out;
1060 	}
1061 
1062 	if (sk->sk_shutdown & SEND_SHUTDOWN) {
1063 		send_sig(SIGPIPE, current, 0);
1064 		err = -EPIPE;
1065 		goto out;
1066 	}
1067 
1068 	if (nr->device == NULL) {
1069 		err = -ENETUNREACH;
1070 		goto out;
1071 	}
1072 
1073 	if (usax) {
1074 		if (msg->msg_namelen < sizeof(sax)) {
1075 			err = -EINVAL;
1076 			goto out;
1077 		}
1078 		sax = *usax;
1079 		if (ax25cmp(&nr->dest_addr, &sax.sax25_call) != 0) {
1080 			err = -EISCONN;
1081 			goto out;
1082 		}
1083 		if (sax.sax25_family != AF_NETROM) {
1084 			err = -EINVAL;
1085 			goto out;
1086 		}
1087 	} else {
1088 		if (sk->sk_state != TCP_ESTABLISHED) {
1089 			err = -ENOTCONN;
1090 			goto out;
1091 		}
1092 		sax.sax25_family = AF_NETROM;
1093 		sax.sax25_call   = nr->dest_addr;
1094 	}
1095 
1096 	/* Build a packet - the conventional user limit is 236 bytes. We can
1097 	   do ludicrously large NetROM frames but must not overflow */
1098 	if (len > 65536) {
1099 		err = -EMSGSIZE;
1100 		goto out;
1101 	}
1102 
1103 	size = len + NR_NETWORK_LEN + NR_TRANSPORT_LEN;
1104 
1105 	if ((skb = sock_alloc_send_skb(sk, size, msg->msg_flags & MSG_DONTWAIT, &err)) == NULL)
1106 		goto out;
1107 
1108 	skb_reserve(skb, size - len);
1109 	skb_reset_transport_header(skb);
1110 
1111 	/*
1112 	 *	Push down the NET/ROM header
1113 	 */
1114 
1115 	asmptr = skb_push(skb, NR_TRANSPORT_LEN);
1116 
1117 	/* Build a NET/ROM Transport header */
1118 
1119 	*asmptr++ = nr->your_index;
1120 	*asmptr++ = nr->your_id;
1121 	*asmptr++ = 0;		/* To be filled in later */
1122 	*asmptr++ = 0;		/*      Ditto            */
1123 	*asmptr++ = NR_INFO;
1124 
1125 	/*
1126 	 *	Put the data on the end
1127 	 */
1128 	skb_put(skb, len);
1129 
1130 	/* User data follows immediately after the NET/ROM transport header */
1131 	if (memcpy_from_msg(skb_transport_header(skb), msg, len)) {
1132 		kfree_skb(skb);
1133 		err = -EFAULT;
1134 		goto out;
1135 	}
1136 
1137 	if (sk->sk_state != TCP_ESTABLISHED) {
1138 		kfree_skb(skb);
1139 		err = -ENOTCONN;
1140 		goto out;
1141 	}
1142 
1143 	nr_output(sk, skb);	/* Shove it onto the queue */
1144 
1145 	err = len;
1146 out:
1147 	release_sock(sk);
1148 	return err;
1149 }
1150 
1151 static int nr_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1152 		      int flags)
1153 {
1154 	struct sock *sk = sock->sk;
1155 	DECLARE_SOCKADDR(struct sockaddr_ax25 *, sax, msg->msg_name);
1156 	size_t copied;
1157 	struct sk_buff *skb;
1158 	int er;
1159 
1160 	/*
1161 	 * This works for seqpacket too. The receiver has ordered the queue for
1162 	 * us! We do one quick check first though
1163 	 */
1164 
1165 	lock_sock(sk);
1166 	if (sk->sk_state != TCP_ESTABLISHED) {
1167 		release_sock(sk);
1168 		return -ENOTCONN;
1169 	}
1170 
1171 	/* Now we can treat all alike */
1172 	skb = skb_recv_datagram(sk, flags, &er);
1173 	if (!skb) {
1174 		release_sock(sk);
1175 		return er;
1176 	}
1177 
1178 	skb_reset_transport_header(skb);
1179 	copied     = skb->len;
1180 
1181 	if (copied > size) {
1182 		copied = size;
1183 		msg->msg_flags |= MSG_TRUNC;
1184 	}
1185 
1186 	er = skb_copy_datagram_msg(skb, 0, msg, copied);
1187 	if (er < 0) {
1188 		skb_free_datagram(sk, skb);
1189 		release_sock(sk);
1190 		return er;
1191 	}
1192 
1193 	if (sax != NULL) {
1194 		memset(sax, 0, sizeof(*sax));
1195 		sax->sax25_family = AF_NETROM;
1196 		skb_copy_from_linear_data_offset(skb, 7, sax->sax25_call.ax25_call,
1197 			      AX25_ADDR_LEN);
1198 		msg->msg_namelen = sizeof(*sax);
1199 	}
1200 
1201 	skb_free_datagram(sk, skb);
1202 
1203 	release_sock(sk);
1204 	return copied;
1205 }
1206 
1207 
1208 static int nr_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1209 {
1210 	struct sock *sk = sock->sk;
1211 	void __user *argp = (void __user *)arg;
1212 
1213 	switch (cmd) {
1214 	case TIOCOUTQ: {
1215 		long amount;
1216 
1217 		lock_sock(sk);
1218 		amount = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
1219 		if (amount < 0)
1220 			amount = 0;
1221 		release_sock(sk);
1222 		return put_user(amount, (int __user *)argp);
1223 	}
1224 
1225 	case TIOCINQ: {
1226 		struct sk_buff *skb;
1227 		long amount = 0L;
1228 
1229 		lock_sock(sk);
1230 		/* These two are safe on a single CPU system as only user tasks fiddle here */
1231 		if ((skb = skb_peek(&sk->sk_receive_queue)) != NULL)
1232 			amount = skb->len;
1233 		release_sock(sk);
1234 		return put_user(amount, (int __user *)argp);
1235 	}
1236 
1237 	case SIOCGIFADDR:
1238 	case SIOCSIFADDR:
1239 	case SIOCGIFDSTADDR:
1240 	case SIOCSIFDSTADDR:
1241 	case SIOCGIFBRDADDR:
1242 	case SIOCSIFBRDADDR:
1243 	case SIOCGIFNETMASK:
1244 	case SIOCSIFNETMASK:
1245 	case SIOCGIFMETRIC:
1246 	case SIOCSIFMETRIC:
1247 		return -EINVAL;
1248 
1249 	case SIOCADDRT:
1250 	case SIOCDELRT:
1251 	case SIOCNRDECOBS:
1252 		if (!capable(CAP_NET_ADMIN))
1253 			return -EPERM;
1254 		return nr_rt_ioctl(cmd, argp);
1255 
1256 	default:
1257 		return -ENOIOCTLCMD;
1258 	}
1259 
1260 	return 0;
1261 }
1262 
1263 #ifdef CONFIG_PROC_FS
1264 
1265 static void *nr_info_start(struct seq_file *seq, loff_t *pos)
1266 	__acquires(&nr_list_lock)
1267 {
1268 	spin_lock_bh(&nr_list_lock);
1269 	return seq_hlist_start_head(&nr_list, *pos);
1270 }
1271 
1272 static void *nr_info_next(struct seq_file *seq, void *v, loff_t *pos)
1273 {
1274 	return seq_hlist_next(v, &nr_list, pos);
1275 }
1276 
1277 static void nr_info_stop(struct seq_file *seq, void *v)
1278 	__releases(&nr_list_lock)
1279 {
1280 	spin_unlock_bh(&nr_list_lock);
1281 }
1282 
1283 static int nr_info_show(struct seq_file *seq, void *v)
1284 {
1285 	struct sock *s = sk_entry(v);
1286 	struct net_device *dev;
1287 	struct nr_sock *nr;
1288 	const char *devname;
1289 	char buf[11];
1290 
1291 	if (v == SEQ_START_TOKEN)
1292 		seq_puts(seq,
1293 "user_addr dest_node src_node  dev    my  your  st  vs  vr  va    t1     t2     t4      idle   n2  wnd Snd-Q Rcv-Q inode\n");
1294 
1295 	else {
1296 
1297 		bh_lock_sock(s);
1298 		nr = nr_sk(s);
1299 
1300 		if ((dev = nr->device) == NULL)
1301 			devname = "???";
1302 		else
1303 			devname = dev->name;
1304 
1305 		seq_printf(seq, "%-9s ", ax2asc(buf, &nr->user_addr));
1306 		seq_printf(seq, "%-9s ", ax2asc(buf, &nr->dest_addr));
1307 		seq_printf(seq,
1308 "%-9s %-3s  %02X/%02X %02X/%02X %2d %3d %3d %3d %3lu/%03lu %2lu/%02lu %3lu/%03lu %3lu/%03lu %2d/%02d %3d %5d %5d %ld\n",
1309 			ax2asc(buf, &nr->source_addr),
1310 			devname,
1311 			nr->my_index,
1312 			nr->my_id,
1313 			nr->your_index,
1314 			nr->your_id,
1315 			nr->state,
1316 			nr->vs,
1317 			nr->vr,
1318 			nr->va,
1319 			ax25_display_timer(&nr->t1timer) / HZ,
1320 			nr->t1 / HZ,
1321 			ax25_display_timer(&nr->t2timer) / HZ,
1322 			nr->t2 / HZ,
1323 			ax25_display_timer(&nr->t4timer) / HZ,
1324 			nr->t4 / HZ,
1325 			ax25_display_timer(&nr->idletimer) / (60 * HZ),
1326 			nr->idle / (60 * HZ),
1327 			nr->n2count,
1328 			nr->n2,
1329 			nr->window,
1330 			sk_wmem_alloc_get(s),
1331 			sk_rmem_alloc_get(s),
1332 			s->sk_socket ? SOCK_INODE(s->sk_socket)->i_ino : 0L);
1333 
1334 		bh_unlock_sock(s);
1335 	}
1336 	return 0;
1337 }
1338 
1339 static const struct seq_operations nr_info_seqops = {
1340 	.start = nr_info_start,
1341 	.next = nr_info_next,
1342 	.stop = nr_info_stop,
1343 	.show = nr_info_show,
1344 };
1345 #endif	/* CONFIG_PROC_FS */
1346 
1347 static const struct net_proto_family nr_family_ops = {
1348 	.family		=	PF_NETROM,
1349 	.create		=	nr_create,
1350 	.owner		=	THIS_MODULE,
1351 };
1352 
1353 static const struct proto_ops nr_proto_ops = {
1354 	.family		=	PF_NETROM,
1355 	.owner		=	THIS_MODULE,
1356 	.release	=	nr_release,
1357 	.bind		=	nr_bind,
1358 	.connect	=	nr_connect,
1359 	.socketpair	=	sock_no_socketpair,
1360 	.accept		=	nr_accept,
1361 	.getname	=	nr_getname,
1362 	.poll		=	datagram_poll,
1363 	.ioctl		=	nr_ioctl,
1364 	.gettstamp	=	sock_gettstamp,
1365 	.listen		=	nr_listen,
1366 	.shutdown	=	sock_no_shutdown,
1367 	.setsockopt	=	nr_setsockopt,
1368 	.getsockopt	=	nr_getsockopt,
1369 	.sendmsg	=	nr_sendmsg,
1370 	.recvmsg	=	nr_recvmsg,
1371 	.mmap		=	sock_no_mmap,
1372 };
1373 
1374 static struct notifier_block nr_dev_notifier = {
1375 	.notifier_call	=	nr_device_event,
1376 };
1377 
1378 static struct net_device **dev_nr;
1379 
1380 static struct ax25_protocol nr_pid = {
1381 	.pid	= AX25_P_NETROM,
1382 	.func	= nr_route_frame
1383 };
1384 
1385 static struct ax25_linkfail nr_linkfail_notifier = {
1386 	.func	= nr_link_failed,
1387 };
1388 
1389 static int __init nr_proto_init(void)
1390 {
1391 	int i;
1392 	int rc = proto_register(&nr_proto, 0);
1393 
1394 	if (rc)
1395 		return rc;
1396 
1397 	if (nr_ndevs > 0x7fffffff/sizeof(struct net_device *)) {
1398 		pr_err("NET/ROM: %s - nr_ndevs parameter too large\n",
1399 		       __func__);
1400 		rc = -EINVAL;
1401 		goto unregister_proto;
1402 	}
1403 
1404 	dev_nr = kcalloc(nr_ndevs, sizeof(struct net_device *), GFP_KERNEL);
1405 	if (!dev_nr) {
1406 		pr_err("NET/ROM: %s - unable to allocate device array\n",
1407 		       __func__);
1408 		rc = -ENOMEM;
1409 		goto unregister_proto;
1410 	}
1411 
1412 	for (i = 0; i < nr_ndevs; i++) {
1413 		char name[IFNAMSIZ];
1414 		struct net_device *dev;
1415 
1416 		sprintf(name, "nr%d", i);
1417 		dev = alloc_netdev(0, name, NET_NAME_UNKNOWN, nr_setup);
1418 		if (!dev) {
1419 			rc = -ENOMEM;
1420 			goto fail;
1421 		}
1422 
1423 		dev->base_addr = i;
1424 		rc = register_netdev(dev);
1425 		if (rc) {
1426 			free_netdev(dev);
1427 			goto fail;
1428 		}
1429 		nr_set_lockdep_key(dev);
1430 		dev_nr[i] = dev;
1431 	}
1432 
1433 	rc = sock_register(&nr_family_ops);
1434 	if (rc)
1435 		goto fail;
1436 
1437 	rc = register_netdevice_notifier(&nr_dev_notifier);
1438 	if (rc)
1439 		goto out_sock;
1440 
1441 	ax25_register_pid(&nr_pid);
1442 	ax25_linkfail_register(&nr_linkfail_notifier);
1443 
1444 #ifdef CONFIG_SYSCTL
1445 	rc = nr_register_sysctl();
1446 	if (rc)
1447 		goto out_sysctl;
1448 #endif
1449 
1450 	nr_loopback_init();
1451 
1452 	rc = -ENOMEM;
1453 	if (!proc_create_seq("nr", 0444, init_net.proc_net, &nr_info_seqops))
1454 		goto proc_remove1;
1455 	if (!proc_create_seq("nr_neigh", 0444, init_net.proc_net,
1456 			     &nr_neigh_seqops))
1457 		goto proc_remove2;
1458 	if (!proc_create_seq("nr_nodes", 0444, init_net.proc_net,
1459 			     &nr_node_seqops))
1460 		goto proc_remove3;
1461 
1462 	return 0;
1463 
1464 proc_remove3:
1465 	remove_proc_entry("nr_neigh", init_net.proc_net);
1466 proc_remove2:
1467 	remove_proc_entry("nr", init_net.proc_net);
1468 proc_remove1:
1469 
1470 	nr_loopback_clear();
1471 	nr_rt_free();
1472 
1473 #ifdef CONFIG_SYSCTL
1474 	nr_unregister_sysctl();
1475 out_sysctl:
1476 #endif
1477 	ax25_linkfail_release(&nr_linkfail_notifier);
1478 	ax25_protocol_release(AX25_P_NETROM);
1479 	unregister_netdevice_notifier(&nr_dev_notifier);
1480 out_sock:
1481 	sock_unregister(PF_NETROM);
1482 fail:
1483 	while (--i >= 0) {
1484 		unregister_netdev(dev_nr[i]);
1485 		free_netdev(dev_nr[i]);
1486 	}
1487 	kfree(dev_nr);
1488 unregister_proto:
1489 	proto_unregister(&nr_proto);
1490 	return rc;
1491 }
1492 
1493 module_init(nr_proto_init);
1494 
1495 module_param(nr_ndevs, int, 0);
1496 MODULE_PARM_DESC(nr_ndevs, "number of NET/ROM devices");
1497 
1498 MODULE_AUTHOR("Jonathan Naylor G4KLX <g4klx@g4klx.demon.co.uk>");
1499 MODULE_DESCRIPTION("The amateur radio NET/ROM network and transport layer protocol");
1500 MODULE_LICENSE("GPL");
1501 MODULE_ALIAS_NETPROTO(PF_NETROM);
1502 
1503 static void __exit nr_exit(void)
1504 {
1505 	int i;
1506 
1507 	remove_proc_entry("nr", init_net.proc_net);
1508 	remove_proc_entry("nr_neigh", init_net.proc_net);
1509 	remove_proc_entry("nr_nodes", init_net.proc_net);
1510 	nr_loopback_clear();
1511 
1512 	nr_rt_free();
1513 
1514 #ifdef CONFIG_SYSCTL
1515 	nr_unregister_sysctl();
1516 #endif
1517 
1518 	ax25_linkfail_release(&nr_linkfail_notifier);
1519 	ax25_protocol_release(AX25_P_NETROM);
1520 
1521 	unregister_netdevice_notifier(&nr_dev_notifier);
1522 
1523 	sock_unregister(PF_NETROM);
1524 
1525 	for (i = 0; i < nr_ndevs; i++) {
1526 		struct net_device *dev = dev_nr[i];
1527 		if (dev) {
1528 			unregister_netdev(dev);
1529 			free_netdev(dev);
1530 		}
1531 	}
1532 
1533 	kfree(dev_nr);
1534 	proto_unregister(&nr_proto);
1535 }
1536 module_exit(nr_exit);
1537