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