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1/*
2 * raw.c - Raw sockets for protocol family CAN
3 *
4 * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of Volkswagen nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * Alternatively, provided that this notice is retained in full, this
20 * software may be distributed under the terms of the GNU General
21 * Public License ("GPL") version 2, in which case the provisions of the
22 * GPL apply INSTEAD OF those given above.
23 *
24 * The provided data structures and external interfaces from this code
25 * are not restricted to be used by modules with a GPL compatible license.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
28 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
29 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
30 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
31 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
32 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
33 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
34 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
35 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
36 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
37 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
38 * DAMAGE.
39 *
40 */
41
42#include <linux/module.h>
43#include <linux/init.h>
44#include <linux/uio.h>
45#include <linux/net.h>
46#include <linux/slab.h>
47#include <linux/netdevice.h>
48#include <linux/socket.h>
49#include <linux/if_arp.h>
50#include <linux/skbuff.h>
51#include <linux/can.h>
52#include <linux/can/core.h>
53#include <linux/can/skb.h>
54#include <linux/can/raw.h>
55#include <net/sock.h>
56#include <net/net_namespace.h>
57
58#define CAN_RAW_VERSION CAN_VERSION
59
60MODULE_DESCRIPTION("PF_CAN raw protocol");
61MODULE_LICENSE("Dual BSD/GPL");
62MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>");
63MODULE_ALIAS("can-proto-1");
64
65#define MASK_ALL 0
66
67/*
68 * A raw socket has a list of can_filters attached to it, each receiving
69 * the CAN frames matching that filter. If the filter list is empty,
70 * no CAN frames will be received by the socket. The default after
71 * opening the socket, is to have one filter which receives all frames.
72 * The filter list is allocated dynamically with the exception of the
73 * list containing only one item. This common case is optimized by
74 * storing the single filter in dfilter, to avoid using dynamic memory.
75 */
76
77struct uniqframe {
78 int skbcnt;
79 const struct sk_buff *skb;
80 unsigned int join_rx_count;
81};
82
83struct raw_sock {
84 struct sock sk;
85 int bound;
86 int ifindex;
87 struct notifier_block notifier;
88 int loopback;
89 int recv_own_msgs;
90 int fd_frames;
91 int join_filters;
92 int count; /* number of active filters */
93 struct can_filter dfilter; /* default/single filter */
94 struct can_filter *filter; /* pointer to filter(s) */
95 can_err_mask_t err_mask;
96 struct uniqframe __percpu *uniq;
97};
98
99/*
100 * Return pointer to store the extra msg flags for raw_recvmsg().
101 * We use the space of one unsigned int beyond the 'struct sockaddr_can'
102 * in skb->cb.
103 */
104static inline unsigned int *raw_flags(struct sk_buff *skb)
105{
106 sock_skb_cb_check_size(sizeof(struct sockaddr_can) +
107 sizeof(unsigned int));
108
109 /* return pointer after struct sockaddr_can */
110 return (unsigned int *)(&((struct sockaddr_can *)skb->cb)[1]);
111}
112
113static inline struct raw_sock *raw_sk(const struct sock *sk)
114{
115 return (struct raw_sock *)sk;
116}
117
118static void raw_rcv(struct sk_buff *oskb, void *data)
119{
120 struct sock *sk = (struct sock *)data;
121 struct raw_sock *ro = raw_sk(sk);
122 struct sockaddr_can *addr;
123 struct sk_buff *skb;
124 unsigned int *pflags;
125
126 /* check the received tx sock reference */
127 if (!ro->recv_own_msgs && oskb->sk == sk)
128 return;
129
130 /* do not pass non-CAN2.0 frames to a legacy socket */
131 if (!ro->fd_frames && oskb->len != CAN_MTU)
132 return;
133
134 /* eliminate multiple filter matches for the same skb */
135 if (this_cpu_ptr(ro->uniq)->skb == oskb &&
136 this_cpu_ptr(ro->uniq)->skbcnt == can_skb_prv(oskb)->skbcnt) {
137 if (ro->join_filters) {
138 this_cpu_inc(ro->uniq->join_rx_count);
139 /* drop frame until all enabled filters matched */
140 if (this_cpu_ptr(ro->uniq)->join_rx_count < ro->count)
141 return;
142 } else {
143 return;
144 }
145 } else {
146 this_cpu_ptr(ro->uniq)->skb = oskb;
147 this_cpu_ptr(ro->uniq)->skbcnt = can_skb_prv(oskb)->skbcnt;
148 this_cpu_ptr(ro->uniq)->join_rx_count = 1;
149 /* drop first frame to check all enabled filters? */
150 if (ro->join_filters && ro->count > 1)
151 return;
152 }
153
154 /* clone the given skb to be able to enqueue it into the rcv queue */
155 skb = skb_clone(oskb, GFP_ATOMIC);
156 if (!skb)
157 return;
158
159 /*
160 * Put the datagram to the queue so that raw_recvmsg() can
161 * get it from there. We need to pass the interface index to
162 * raw_recvmsg(). We pass a whole struct sockaddr_can in skb->cb
163 * containing the interface index.
164 */
165
166 sock_skb_cb_check_size(sizeof(struct sockaddr_can));
167 addr = (struct sockaddr_can *)skb->cb;
168 memset(addr, 0, sizeof(*addr));
169 addr->can_family = AF_CAN;
170 addr->can_ifindex = skb->dev->ifindex;
171
172 /* add CAN specific message flags for raw_recvmsg() */
173 pflags = raw_flags(skb);
174 *pflags = 0;
175 if (oskb->sk)
176 *pflags |= MSG_DONTROUTE;
177 if (oskb->sk == sk)
178 *pflags |= MSG_CONFIRM;
179
180 if (sock_queue_rcv_skb(sk, skb) < 0)
181 kfree_skb(skb);
182}
183
184static int raw_enable_filters(struct net_device *dev, struct sock *sk,
185 struct can_filter *filter, int count)
186{
187 int err = 0;
188 int i;
189
190 for (i = 0; i < count; i++) {
191 err = can_rx_register(dev, filter[i].can_id,
192 filter[i].can_mask,
193 raw_rcv, sk, "raw", sk);
194 if (err) {
195 /* clean up successfully registered filters */
196 while (--i >= 0)
197 can_rx_unregister(dev, filter[i].can_id,
198 filter[i].can_mask,
199 raw_rcv, sk);
200 break;
201 }
202 }
203
204 return err;
205}
206
207static int raw_enable_errfilter(struct net_device *dev, struct sock *sk,
208 can_err_mask_t err_mask)
209{
210 int err = 0;
211
212 if (err_mask)
213 err = can_rx_register(dev, 0, err_mask | CAN_ERR_FLAG,
214 raw_rcv, sk, "raw", sk);
215
216 return err;
217}
218
219static void raw_disable_filters(struct net_device *dev, struct sock *sk,
220 struct can_filter *filter, int count)
221{
222 int i;
223
224 for (i = 0; i < count; i++)
225 can_rx_unregister(dev, filter[i].can_id, filter[i].can_mask,
226 raw_rcv, sk);
227}
228
229static inline void raw_disable_errfilter(struct net_device *dev,
230 struct sock *sk,
231 can_err_mask_t err_mask)
232
233{
234 if (err_mask)
235 can_rx_unregister(dev, 0, err_mask | CAN_ERR_FLAG,
236 raw_rcv, sk);
237}
238
239static inline void raw_disable_allfilters(struct net_device *dev,
240 struct sock *sk)
241{
242 struct raw_sock *ro = raw_sk(sk);
243
244 raw_disable_filters(dev, sk, ro->filter, ro->count);
245 raw_disable_errfilter(dev, sk, ro->err_mask);
246}
247
248static int raw_enable_allfilters(struct net_device *dev, struct sock *sk)
249{
250 struct raw_sock *ro = raw_sk(sk);
251 int err;
252
253 err = raw_enable_filters(dev, sk, ro->filter, ro->count);
254 if (!err) {
255 err = raw_enable_errfilter(dev, sk, ro->err_mask);
256 if (err)
257 raw_disable_filters(dev, sk, ro->filter, ro->count);
258 }
259
260 return err;
261}
262
263static int raw_notifier(struct notifier_block *nb,
264 unsigned long msg, void *ptr)
265{
266 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
267 struct raw_sock *ro = container_of(nb, struct raw_sock, notifier);
268 struct sock *sk = &ro->sk;
269
270 if (!net_eq(dev_net(dev), &init_net))
271 return NOTIFY_DONE;
272
273 if (dev->type != ARPHRD_CAN)
274 return NOTIFY_DONE;
275
276 if (ro->ifindex != dev->ifindex)
277 return NOTIFY_DONE;
278
279 switch (msg) {
280
281 case NETDEV_UNREGISTER:
282 lock_sock(sk);
283 /* remove current filters & unregister */
284 if (ro->bound)
285 raw_disable_allfilters(dev, sk);
286
287 if (ro->count > 1)
288 kfree(ro->filter);
289
290 ro->ifindex = 0;
291 ro->bound = 0;
292 ro->count = 0;
293 release_sock(sk);
294
295 sk->sk_err = ENODEV;
296 if (!sock_flag(sk, SOCK_DEAD))
297 sk->sk_error_report(sk);
298 break;
299
300 case NETDEV_DOWN:
301 sk->sk_err = ENETDOWN;
302 if (!sock_flag(sk, SOCK_DEAD))
303 sk->sk_error_report(sk);
304 break;
305 }
306
307 return NOTIFY_DONE;
308}
309
310static int raw_init(struct sock *sk)
311{
312 struct raw_sock *ro = raw_sk(sk);
313
314 ro->bound = 0;
315 ro->ifindex = 0;
316
317 /* set default filter to single entry dfilter */
318 ro->dfilter.can_id = 0;
319 ro->dfilter.can_mask = MASK_ALL;
320 ro->filter = &ro->dfilter;
321 ro->count = 1;
322
323 /* set default loopback behaviour */
324 ro->loopback = 1;
325 ro->recv_own_msgs = 0;
326 ro->fd_frames = 0;
327 ro->join_filters = 0;
328
329 /* alloc_percpu provides zero'ed memory */
330 ro->uniq = alloc_percpu(struct uniqframe);
331 if (unlikely(!ro->uniq))
332 return -ENOMEM;
333
334 /* set notifier */
335 ro->notifier.notifier_call = raw_notifier;
336
337 register_netdevice_notifier(&ro->notifier);
338
339 return 0;
340}
341
342static int raw_release(struct socket *sock)
343{
344 struct sock *sk = sock->sk;
345 struct raw_sock *ro;
346
347 if (!sk)
348 return 0;
349
350 ro = raw_sk(sk);
351
352 unregister_netdevice_notifier(&ro->notifier);
353
354 lock_sock(sk);
355
356 /* remove current filters & unregister */
357 if (ro->bound) {
358 if (ro->ifindex) {
359 struct net_device *dev;
360
361 dev = dev_get_by_index(&init_net, ro->ifindex);
362 if (dev) {
363 raw_disable_allfilters(dev, sk);
364 dev_put(dev);
365 }
366 } else
367 raw_disable_allfilters(NULL, sk);
368 }
369
370 if (ro->count > 1)
371 kfree(ro->filter);
372
373 ro->ifindex = 0;
374 ro->bound = 0;
375 ro->count = 0;
376 free_percpu(ro->uniq);
377
378 sock_orphan(sk);
379 sock->sk = NULL;
380
381 release_sock(sk);
382 sock_put(sk);
383
384 return 0;
385}
386
387static int raw_bind(struct socket *sock, struct sockaddr *uaddr, int len)
388{
389 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
390 struct sock *sk = sock->sk;
391 struct raw_sock *ro = raw_sk(sk);
392 int ifindex;
393 int err = 0;
394 int notify_enetdown = 0;
395
396 if (len < sizeof(*addr))
397 return -EINVAL;
398
399 lock_sock(sk);
400
401 if (ro->bound && addr->can_ifindex == ro->ifindex)
402 goto out;
403
404 if (addr->can_ifindex) {
405 struct net_device *dev;
406
407 dev = dev_get_by_index(&init_net, addr->can_ifindex);
408 if (!dev) {
409 err = -ENODEV;
410 goto out;
411 }
412 if (dev->type != ARPHRD_CAN) {
413 dev_put(dev);
414 err = -ENODEV;
415 goto out;
416 }
417 if (!(dev->flags & IFF_UP))
418 notify_enetdown = 1;
419
420 ifindex = dev->ifindex;
421
422 /* filters set by default/setsockopt */
423 err = raw_enable_allfilters(dev, sk);
424 dev_put(dev);
425 } else {
426 ifindex = 0;
427
428 /* filters set by default/setsockopt */
429 err = raw_enable_allfilters(NULL, sk);
430 }
431
432 if (!err) {
433 if (ro->bound) {
434 /* unregister old filters */
435 if (ro->ifindex) {
436 struct net_device *dev;
437
438 dev = dev_get_by_index(&init_net, ro->ifindex);
439 if (dev) {
440 raw_disable_allfilters(dev, sk);
441 dev_put(dev);
442 }
443 } else
444 raw_disable_allfilters(NULL, sk);
445 }
446 ro->ifindex = ifindex;
447 ro->bound = 1;
448 }
449
450 out:
451 release_sock(sk);
452
453 if (notify_enetdown) {
454 sk->sk_err = ENETDOWN;
455 if (!sock_flag(sk, SOCK_DEAD))
456 sk->sk_error_report(sk);
457 }
458
459 return err;
460}
461
462static int raw_getname(struct socket *sock, struct sockaddr *uaddr,
463 int *len, int peer)
464{
465 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
466 struct sock *sk = sock->sk;
467 struct raw_sock *ro = raw_sk(sk);
468
469 if (peer)
470 return -EOPNOTSUPP;
471
472 memset(addr, 0, sizeof(*addr));
473 addr->can_family = AF_CAN;
474 addr->can_ifindex = ro->ifindex;
475
476 *len = sizeof(*addr);
477
478 return 0;
479}
480
481static int raw_setsockopt(struct socket *sock, int level, int optname,
482 char __user *optval, unsigned int optlen)
483{
484 struct sock *sk = sock->sk;
485 struct raw_sock *ro = raw_sk(sk);
486 struct can_filter *filter = NULL; /* dyn. alloc'ed filters */
487 struct can_filter sfilter; /* single filter */
488 struct net_device *dev = NULL;
489 can_err_mask_t err_mask = 0;
490 int count = 0;
491 int err = 0;
492
493 if (level != SOL_CAN_RAW)
494 return -EINVAL;
495
496 switch (optname) {
497
498 case CAN_RAW_FILTER:
499 if (optlen % sizeof(struct can_filter) != 0)
500 return -EINVAL;
501
502 if (optlen > CAN_RAW_FILTER_MAX * sizeof(struct can_filter))
503 return -EINVAL;
504
505 count = optlen / sizeof(struct can_filter);
506
507 if (count > 1) {
508 /* filter does not fit into dfilter => alloc space */
509 filter = memdup_user(optval, optlen);
510 if (IS_ERR(filter))
511 return PTR_ERR(filter);
512 } else if (count == 1) {
513 if (copy_from_user(&sfilter, optval, sizeof(sfilter)))
514 return -EFAULT;
515 }
516
517 lock_sock(sk);
518
519 if (ro->bound && ro->ifindex)
520 dev = dev_get_by_index(&init_net, ro->ifindex);
521
522 if (ro->bound) {
523 /* (try to) register the new filters */
524 if (count == 1)
525 err = raw_enable_filters(dev, sk, &sfilter, 1);
526 else
527 err = raw_enable_filters(dev, sk, filter,
528 count);
529 if (err) {
530 if (count > 1)
531 kfree(filter);
532 goto out_fil;
533 }
534
535 /* remove old filter registrations */
536 raw_disable_filters(dev, sk, ro->filter, ro->count);
537 }
538
539 /* remove old filter space */
540 if (ro->count > 1)
541 kfree(ro->filter);
542
543 /* link new filters to the socket */
544 if (count == 1) {
545 /* copy filter data for single filter */
546 ro->dfilter = sfilter;
547 filter = &ro->dfilter;
548 }
549 ro->filter = filter;
550 ro->count = count;
551
552 out_fil:
553 if (dev)
554 dev_put(dev);
555
556 release_sock(sk);
557
558 break;
559
560 case CAN_RAW_ERR_FILTER:
561 if (optlen != sizeof(err_mask))
562 return -EINVAL;
563
564 if (copy_from_user(&err_mask, optval, optlen))
565 return -EFAULT;
566
567 err_mask &= CAN_ERR_MASK;
568
569 lock_sock(sk);
570
571 if (ro->bound && ro->ifindex)
572 dev = dev_get_by_index(&init_net, ro->ifindex);
573
574 /* remove current error mask */
575 if (ro->bound) {
576 /* (try to) register the new err_mask */
577 err = raw_enable_errfilter(dev, sk, err_mask);
578
579 if (err)
580 goto out_err;
581
582 /* remove old err_mask registration */
583 raw_disable_errfilter(dev, sk, ro->err_mask);
584 }
585
586 /* link new err_mask to the socket */
587 ro->err_mask = err_mask;
588
589 out_err:
590 if (dev)
591 dev_put(dev);
592
593 release_sock(sk);
594
595 break;
596
597 case CAN_RAW_LOOPBACK:
598 if (optlen != sizeof(ro->loopback))
599 return -EINVAL;
600
601 if (copy_from_user(&ro->loopback, optval, optlen))
602 return -EFAULT;
603
604 break;
605
606 case CAN_RAW_RECV_OWN_MSGS:
607 if (optlen != sizeof(ro->recv_own_msgs))
608 return -EINVAL;
609
610 if (copy_from_user(&ro->recv_own_msgs, optval, optlen))
611 return -EFAULT;
612
613 break;
614
615 case CAN_RAW_FD_FRAMES:
616 if (optlen != sizeof(ro->fd_frames))
617 return -EINVAL;
618
619 if (copy_from_user(&ro->fd_frames, optval, optlen))
620 return -EFAULT;
621
622 break;
623
624 case CAN_RAW_JOIN_FILTERS:
625 if (optlen != sizeof(ro->join_filters))
626 return -EINVAL;
627
628 if (copy_from_user(&ro->join_filters, optval, optlen))
629 return -EFAULT;
630
631 break;
632
633 default:
634 return -ENOPROTOOPT;
635 }
636 return err;
637}
638
639static int raw_getsockopt(struct socket *sock, int level, int optname,
640 char __user *optval, int __user *optlen)
641{
642 struct sock *sk = sock->sk;
643 struct raw_sock *ro = raw_sk(sk);
644 int len;
645 void *val;
646 int err = 0;
647
648 if (level != SOL_CAN_RAW)
649 return -EINVAL;
650 if (get_user(len, optlen))
651 return -EFAULT;
652 if (len < 0)
653 return -EINVAL;
654
655 switch (optname) {
656
657 case CAN_RAW_FILTER:
658 lock_sock(sk);
659 if (ro->count > 0) {
660 int fsize = ro->count * sizeof(struct can_filter);
661 if (len > fsize)
662 len = fsize;
663 if (copy_to_user(optval, ro->filter, len))
664 err = -EFAULT;
665 } else
666 len = 0;
667 release_sock(sk);
668
669 if (!err)
670 err = put_user(len, optlen);
671 return err;
672
673 case CAN_RAW_ERR_FILTER:
674 if (len > sizeof(can_err_mask_t))
675 len = sizeof(can_err_mask_t);
676 val = &ro->err_mask;
677 break;
678
679 case CAN_RAW_LOOPBACK:
680 if (len > sizeof(int))
681 len = sizeof(int);
682 val = &ro->loopback;
683 break;
684
685 case CAN_RAW_RECV_OWN_MSGS:
686 if (len > sizeof(int))
687 len = sizeof(int);
688 val = &ro->recv_own_msgs;
689 break;
690
691 case CAN_RAW_FD_FRAMES:
692 if (len > sizeof(int))
693 len = sizeof(int);
694 val = &ro->fd_frames;
695 break;
696
697 case CAN_RAW_JOIN_FILTERS:
698 if (len > sizeof(int))
699 len = sizeof(int);
700 val = &ro->join_filters;
701 break;
702
703 default:
704 return -ENOPROTOOPT;
705 }
706
707 if (put_user(len, optlen))
708 return -EFAULT;
709 if (copy_to_user(optval, val, len))
710 return -EFAULT;
711 return 0;
712}
713
714static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
715{
716 struct sock *sk = sock->sk;
717 struct raw_sock *ro = raw_sk(sk);
718 struct sk_buff *skb;
719 struct net_device *dev;
720 int ifindex;
721 int err;
722
723 if (msg->msg_name) {
724 DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name);
725
726 if (msg->msg_namelen < sizeof(*addr))
727 return -EINVAL;
728
729 if (addr->can_family != AF_CAN)
730 return -EINVAL;
731
732 ifindex = addr->can_ifindex;
733 } else
734 ifindex = ro->ifindex;
735
736 if (ro->fd_frames) {
737 if (unlikely(size != CANFD_MTU && size != CAN_MTU))
738 return -EINVAL;
739 } else {
740 if (unlikely(size != CAN_MTU))
741 return -EINVAL;
742 }
743
744 dev = dev_get_by_index(&init_net, ifindex);
745 if (!dev)
746 return -ENXIO;
747
748 skb = sock_alloc_send_skb(sk, size + sizeof(struct can_skb_priv),
749 msg->msg_flags & MSG_DONTWAIT, &err);
750 if (!skb)
751 goto put_dev;
752
753 can_skb_reserve(skb);
754 can_skb_prv(skb)->ifindex = dev->ifindex;
755 can_skb_prv(skb)->skbcnt = 0;
756
757 err = memcpy_from_msg(skb_put(skb, size), msg, size);
758 if (err < 0)
759 goto free_skb;
760
761 sock_tx_timestamp(sk, sk->sk_tsflags, &skb_shinfo(skb)->tx_flags);
762
763 skb->dev = dev;
764 skb->sk = sk;
765 skb->priority = sk->sk_priority;
766
767 err = can_send(skb, ro->loopback);
768
769 dev_put(dev);
770
771 if (err)
772 goto send_failed;
773
774 return size;
775
776free_skb:
777 kfree_skb(skb);
778put_dev:
779 dev_put(dev);
780send_failed:
781 return err;
782}
783
784static int raw_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
785 int flags)
786{
787 struct sock *sk = sock->sk;
788 struct sk_buff *skb;
789 int err = 0;
790 int noblock;
791
792 noblock = flags & MSG_DONTWAIT;
793 flags &= ~MSG_DONTWAIT;
794
795 skb = skb_recv_datagram(sk, flags, noblock, &err);
796 if (!skb)
797 return err;
798
799 if (size < skb->len)
800 msg->msg_flags |= MSG_TRUNC;
801 else
802 size = skb->len;
803
804 err = memcpy_to_msg(msg, skb->data, size);
805 if (err < 0) {
806 skb_free_datagram(sk, skb);
807 return err;
808 }
809
810 sock_recv_ts_and_drops(msg, sk, skb);
811
812 if (msg->msg_name) {
813 __sockaddr_check_size(sizeof(struct sockaddr_can));
814 msg->msg_namelen = sizeof(struct sockaddr_can);
815 memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
816 }
817
818 /* assign the flags that have been recorded in raw_rcv() */
819 msg->msg_flags |= *(raw_flags(skb));
820
821 skb_free_datagram(sk, skb);
822
823 return size;
824}
825
826static const struct proto_ops raw_ops = {
827 .family = PF_CAN,
828 .release = raw_release,
829 .bind = raw_bind,
830 .connect = sock_no_connect,
831 .socketpair = sock_no_socketpair,
832 .accept = sock_no_accept,
833 .getname = raw_getname,
834 .poll = datagram_poll,
835 .ioctl = can_ioctl, /* use can_ioctl() from af_can.c */
836 .listen = sock_no_listen,
837 .shutdown = sock_no_shutdown,
838 .setsockopt = raw_setsockopt,
839 .getsockopt = raw_getsockopt,
840 .sendmsg = raw_sendmsg,
841 .recvmsg = raw_recvmsg,
842 .mmap = sock_no_mmap,
843 .sendpage = sock_no_sendpage,
844};
845
846static struct proto raw_proto __read_mostly = {
847 .name = "CAN_RAW",
848 .owner = THIS_MODULE,
849 .obj_size = sizeof(struct raw_sock),
850 .init = raw_init,
851};
852
853static const struct can_proto raw_can_proto = {
854 .type = SOCK_RAW,
855 .protocol = CAN_RAW,
856 .ops = &raw_ops,
857 .prot = &raw_proto,
858};
859
860static __init int raw_module_init(void)
861{
862 int err;
863
864 pr_info("can: raw protocol (rev " CAN_RAW_VERSION ")\n");
865
866 err = can_proto_register(&raw_can_proto);
867 if (err < 0)
868 printk(KERN_ERR "can: registration of raw protocol failed\n");
869
870 return err;
871}
872
873static __exit void raw_module_exit(void)
874{
875 can_proto_unregister(&raw_can_proto);
876}
877
878module_init(raw_module_init);
879module_exit(raw_module_exit);
1// SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)
2/* raw.c - Raw sockets for protocol family CAN
3 *
4 * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of Volkswagen nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * Alternatively, provided that this notice is retained in full, this
20 * software may be distributed under the terms of the GNU General
21 * Public License ("GPL") version 2, in which case the provisions of the
22 * GPL apply INSTEAD OF those given above.
23 *
24 * The provided data structures and external interfaces from this code
25 * are not restricted to be used by modules with a GPL compatible license.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
28 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
29 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
30 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
31 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
32 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
33 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
34 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
35 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
36 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
37 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
38 * DAMAGE.
39 *
40 */
41
42#include <linux/module.h>
43#include <linux/init.h>
44#include <linux/uio.h>
45#include <linux/net.h>
46#include <linux/slab.h>
47#include <linux/netdevice.h>
48#include <linux/socket.h>
49#include <linux/if_arp.h>
50#include <linux/skbuff.h>
51#include <linux/can.h>
52#include <linux/can/core.h>
53#include <linux/can/skb.h>
54#include <linux/can/raw.h>
55#include <net/sock.h>
56#include <net/net_namespace.h>
57
58#define CAN_RAW_VERSION CAN_VERSION
59
60MODULE_DESCRIPTION("PF_CAN raw protocol");
61MODULE_LICENSE("Dual BSD/GPL");
62MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>");
63MODULE_ALIAS("can-proto-1");
64
65#define MASK_ALL 0
66
67/* A raw socket has a list of can_filters attached to it, each receiving
68 * the CAN frames matching that filter. If the filter list is empty,
69 * no CAN frames will be received by the socket. The default after
70 * opening the socket, is to have one filter which receives all frames.
71 * The filter list is allocated dynamically with the exception of the
72 * list containing only one item. This common case is optimized by
73 * storing the single filter in dfilter, to avoid using dynamic memory.
74 */
75
76struct uniqframe {
77 int skbcnt;
78 const struct sk_buff *skb;
79 unsigned int join_rx_count;
80};
81
82struct raw_sock {
83 struct sock sk;
84 int bound;
85 int ifindex;
86 struct notifier_block notifier;
87 int loopback;
88 int recv_own_msgs;
89 int fd_frames;
90 int join_filters;
91 int count; /* number of active filters */
92 struct can_filter dfilter; /* default/single filter */
93 struct can_filter *filter; /* pointer to filter(s) */
94 can_err_mask_t err_mask;
95 struct uniqframe __percpu *uniq;
96};
97
98/* Return pointer to store the extra msg flags for raw_recvmsg().
99 * We use the space of one unsigned int beyond the 'struct sockaddr_can'
100 * in skb->cb.
101 */
102static inline unsigned int *raw_flags(struct sk_buff *skb)
103{
104 sock_skb_cb_check_size(sizeof(struct sockaddr_can) +
105 sizeof(unsigned int));
106
107 /* return pointer after struct sockaddr_can */
108 return (unsigned int *)(&((struct sockaddr_can *)skb->cb)[1]);
109}
110
111static inline struct raw_sock *raw_sk(const struct sock *sk)
112{
113 return (struct raw_sock *)sk;
114}
115
116static void raw_rcv(struct sk_buff *oskb, void *data)
117{
118 struct sock *sk = (struct sock *)data;
119 struct raw_sock *ro = raw_sk(sk);
120 struct sockaddr_can *addr;
121 struct sk_buff *skb;
122 unsigned int *pflags;
123
124 /* check the received tx sock reference */
125 if (!ro->recv_own_msgs && oskb->sk == sk)
126 return;
127
128 /* do not pass non-CAN2.0 frames to a legacy socket */
129 if (!ro->fd_frames && oskb->len != CAN_MTU)
130 return;
131
132 /* eliminate multiple filter matches for the same skb */
133 if (this_cpu_ptr(ro->uniq)->skb == oskb &&
134 this_cpu_ptr(ro->uniq)->skbcnt == can_skb_prv(oskb)->skbcnt) {
135 if (ro->join_filters) {
136 this_cpu_inc(ro->uniq->join_rx_count);
137 /* drop frame until all enabled filters matched */
138 if (this_cpu_ptr(ro->uniq)->join_rx_count < ro->count)
139 return;
140 } else {
141 return;
142 }
143 } else {
144 this_cpu_ptr(ro->uniq)->skb = oskb;
145 this_cpu_ptr(ro->uniq)->skbcnt = can_skb_prv(oskb)->skbcnt;
146 this_cpu_ptr(ro->uniq)->join_rx_count = 1;
147 /* drop first frame to check all enabled filters? */
148 if (ro->join_filters && ro->count > 1)
149 return;
150 }
151
152 /* clone the given skb to be able to enqueue it into the rcv queue */
153 skb = skb_clone(oskb, GFP_ATOMIC);
154 if (!skb)
155 return;
156
157 /* Put the datagram to the queue so that raw_recvmsg() can
158 * get it from there. We need to pass the interface index to
159 * raw_recvmsg(). We pass a whole struct sockaddr_can in skb->cb
160 * containing the interface index.
161 */
162
163 sock_skb_cb_check_size(sizeof(struct sockaddr_can));
164 addr = (struct sockaddr_can *)skb->cb;
165 memset(addr, 0, sizeof(*addr));
166 addr->can_family = AF_CAN;
167 addr->can_ifindex = skb->dev->ifindex;
168
169 /* add CAN specific message flags for raw_recvmsg() */
170 pflags = raw_flags(skb);
171 *pflags = 0;
172 if (oskb->sk)
173 *pflags |= MSG_DONTROUTE;
174 if (oskb->sk == sk)
175 *pflags |= MSG_CONFIRM;
176
177 if (sock_queue_rcv_skb(sk, skb) < 0)
178 kfree_skb(skb);
179}
180
181static int raw_enable_filters(struct net *net, struct net_device *dev,
182 struct sock *sk, struct can_filter *filter,
183 int count)
184{
185 int err = 0;
186 int i;
187
188 for (i = 0; i < count; i++) {
189 err = can_rx_register(net, dev, filter[i].can_id,
190 filter[i].can_mask,
191 raw_rcv, sk, "raw", sk);
192 if (err) {
193 /* clean up successfully registered filters */
194 while (--i >= 0)
195 can_rx_unregister(net, dev, filter[i].can_id,
196 filter[i].can_mask,
197 raw_rcv, sk);
198 break;
199 }
200 }
201
202 return err;
203}
204
205static int raw_enable_errfilter(struct net *net, struct net_device *dev,
206 struct sock *sk, can_err_mask_t err_mask)
207{
208 int err = 0;
209
210 if (err_mask)
211 err = can_rx_register(net, dev, 0, err_mask | CAN_ERR_FLAG,
212 raw_rcv, sk, "raw", sk);
213
214 return err;
215}
216
217static void raw_disable_filters(struct net *net, struct net_device *dev,
218 struct sock *sk, struct can_filter *filter,
219 int count)
220{
221 int i;
222
223 for (i = 0; i < count; i++)
224 can_rx_unregister(net, dev, filter[i].can_id,
225 filter[i].can_mask, raw_rcv, sk);
226}
227
228static inline void raw_disable_errfilter(struct net *net,
229 struct net_device *dev,
230 struct sock *sk,
231 can_err_mask_t err_mask)
232
233{
234 if (err_mask)
235 can_rx_unregister(net, dev, 0, err_mask | CAN_ERR_FLAG,
236 raw_rcv, sk);
237}
238
239static inline void raw_disable_allfilters(struct net *net,
240 struct net_device *dev,
241 struct sock *sk)
242{
243 struct raw_sock *ro = raw_sk(sk);
244
245 raw_disable_filters(net, dev, sk, ro->filter, ro->count);
246 raw_disable_errfilter(net, dev, sk, ro->err_mask);
247}
248
249static int raw_enable_allfilters(struct net *net, struct net_device *dev,
250 struct sock *sk)
251{
252 struct raw_sock *ro = raw_sk(sk);
253 int err;
254
255 err = raw_enable_filters(net, dev, sk, ro->filter, ro->count);
256 if (!err) {
257 err = raw_enable_errfilter(net, dev, sk, ro->err_mask);
258 if (err)
259 raw_disable_filters(net, dev, sk, ro->filter,
260 ro->count);
261 }
262
263 return err;
264}
265
266static int raw_notifier(struct notifier_block *nb,
267 unsigned long msg, void *ptr)
268{
269 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
270 struct raw_sock *ro = container_of(nb, struct raw_sock, notifier);
271 struct sock *sk = &ro->sk;
272
273 if (!net_eq(dev_net(dev), sock_net(sk)))
274 return NOTIFY_DONE;
275
276 if (dev->type != ARPHRD_CAN)
277 return NOTIFY_DONE;
278
279 if (ro->ifindex != dev->ifindex)
280 return NOTIFY_DONE;
281
282 switch (msg) {
283 case NETDEV_UNREGISTER:
284 lock_sock(sk);
285 /* remove current filters & unregister */
286 if (ro->bound)
287 raw_disable_allfilters(dev_net(dev), dev, sk);
288
289 if (ro->count > 1)
290 kfree(ro->filter);
291
292 ro->ifindex = 0;
293 ro->bound = 0;
294 ro->count = 0;
295 release_sock(sk);
296
297 sk->sk_err = ENODEV;
298 if (!sock_flag(sk, SOCK_DEAD))
299 sk->sk_error_report(sk);
300 break;
301
302 case NETDEV_DOWN:
303 sk->sk_err = ENETDOWN;
304 if (!sock_flag(sk, SOCK_DEAD))
305 sk->sk_error_report(sk);
306 break;
307 }
308
309 return NOTIFY_DONE;
310}
311
312static int raw_init(struct sock *sk)
313{
314 struct raw_sock *ro = raw_sk(sk);
315
316 ro->bound = 0;
317 ro->ifindex = 0;
318
319 /* set default filter to single entry dfilter */
320 ro->dfilter.can_id = 0;
321 ro->dfilter.can_mask = MASK_ALL;
322 ro->filter = &ro->dfilter;
323 ro->count = 1;
324
325 /* set default loopback behaviour */
326 ro->loopback = 1;
327 ro->recv_own_msgs = 0;
328 ro->fd_frames = 0;
329 ro->join_filters = 0;
330
331 /* alloc_percpu provides zero'ed memory */
332 ro->uniq = alloc_percpu(struct uniqframe);
333 if (unlikely(!ro->uniq))
334 return -ENOMEM;
335
336 /* set notifier */
337 ro->notifier.notifier_call = raw_notifier;
338
339 register_netdevice_notifier(&ro->notifier);
340
341 return 0;
342}
343
344static int raw_release(struct socket *sock)
345{
346 struct sock *sk = sock->sk;
347 struct raw_sock *ro;
348
349 if (!sk)
350 return 0;
351
352 ro = raw_sk(sk);
353
354 unregister_netdevice_notifier(&ro->notifier);
355
356 lock_sock(sk);
357
358 /* remove current filters & unregister */
359 if (ro->bound) {
360 if (ro->ifindex) {
361 struct net_device *dev;
362
363 dev = dev_get_by_index(sock_net(sk), ro->ifindex);
364 if (dev) {
365 raw_disable_allfilters(dev_net(dev), dev, sk);
366 dev_put(dev);
367 }
368 } else {
369 raw_disable_allfilters(sock_net(sk), NULL, sk);
370 }
371 }
372
373 if (ro->count > 1)
374 kfree(ro->filter);
375
376 ro->ifindex = 0;
377 ro->bound = 0;
378 ro->count = 0;
379 free_percpu(ro->uniq);
380
381 sock_orphan(sk);
382 sock->sk = NULL;
383
384 release_sock(sk);
385 sock_put(sk);
386
387 return 0;
388}
389
390static int raw_bind(struct socket *sock, struct sockaddr *uaddr, int len)
391{
392 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
393 struct sock *sk = sock->sk;
394 struct raw_sock *ro = raw_sk(sk);
395 int ifindex;
396 int err = 0;
397 int notify_enetdown = 0;
398
399 if (len < CAN_REQUIRED_SIZE(*addr, can_ifindex))
400 return -EINVAL;
401 if (addr->can_family != AF_CAN)
402 return -EINVAL;
403
404 lock_sock(sk);
405
406 if (ro->bound && addr->can_ifindex == ro->ifindex)
407 goto out;
408
409 if (addr->can_ifindex) {
410 struct net_device *dev;
411
412 dev = dev_get_by_index(sock_net(sk), addr->can_ifindex);
413 if (!dev) {
414 err = -ENODEV;
415 goto out;
416 }
417 if (dev->type != ARPHRD_CAN) {
418 dev_put(dev);
419 err = -ENODEV;
420 goto out;
421 }
422 if (!(dev->flags & IFF_UP))
423 notify_enetdown = 1;
424
425 ifindex = dev->ifindex;
426
427 /* filters set by default/setsockopt */
428 err = raw_enable_allfilters(sock_net(sk), dev, sk);
429 dev_put(dev);
430 } else {
431 ifindex = 0;
432
433 /* filters set by default/setsockopt */
434 err = raw_enable_allfilters(sock_net(sk), NULL, sk);
435 }
436
437 if (!err) {
438 if (ro->bound) {
439 /* unregister old filters */
440 if (ro->ifindex) {
441 struct net_device *dev;
442
443 dev = dev_get_by_index(sock_net(sk),
444 ro->ifindex);
445 if (dev) {
446 raw_disable_allfilters(dev_net(dev),
447 dev, sk);
448 dev_put(dev);
449 }
450 } else {
451 raw_disable_allfilters(sock_net(sk), NULL, sk);
452 }
453 }
454 ro->ifindex = ifindex;
455 ro->bound = 1;
456 }
457
458 out:
459 release_sock(sk);
460
461 if (notify_enetdown) {
462 sk->sk_err = ENETDOWN;
463 if (!sock_flag(sk, SOCK_DEAD))
464 sk->sk_error_report(sk);
465 }
466
467 return err;
468}
469
470static int raw_getname(struct socket *sock, struct sockaddr *uaddr,
471 int peer)
472{
473 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
474 struct sock *sk = sock->sk;
475 struct raw_sock *ro = raw_sk(sk);
476
477 if (peer)
478 return -EOPNOTSUPP;
479
480 memset(addr, 0, sizeof(*addr));
481 addr->can_family = AF_CAN;
482 addr->can_ifindex = ro->ifindex;
483
484 return sizeof(*addr);
485}
486
487static int raw_setsockopt(struct socket *sock, int level, int optname,
488 char __user *optval, unsigned int optlen)
489{
490 struct sock *sk = sock->sk;
491 struct raw_sock *ro = raw_sk(sk);
492 struct can_filter *filter = NULL; /* dyn. alloc'ed filters */
493 struct can_filter sfilter; /* single filter */
494 struct net_device *dev = NULL;
495 can_err_mask_t err_mask = 0;
496 int count = 0;
497 int err = 0;
498
499 if (level != SOL_CAN_RAW)
500 return -EINVAL;
501
502 switch (optname) {
503 case CAN_RAW_FILTER:
504 if (optlen % sizeof(struct can_filter) != 0)
505 return -EINVAL;
506
507 if (optlen > CAN_RAW_FILTER_MAX * sizeof(struct can_filter))
508 return -EINVAL;
509
510 count = optlen / sizeof(struct can_filter);
511
512 if (count > 1) {
513 /* filter does not fit into dfilter => alloc space */
514 filter = memdup_user(optval, optlen);
515 if (IS_ERR(filter))
516 return PTR_ERR(filter);
517 } else if (count == 1) {
518 if (copy_from_user(&sfilter, optval, sizeof(sfilter)))
519 return -EFAULT;
520 }
521
522 lock_sock(sk);
523
524 if (ro->bound && ro->ifindex)
525 dev = dev_get_by_index(sock_net(sk), ro->ifindex);
526
527 if (ro->bound) {
528 /* (try to) register the new filters */
529 if (count == 1)
530 err = raw_enable_filters(sock_net(sk), dev, sk,
531 &sfilter, 1);
532 else
533 err = raw_enable_filters(sock_net(sk), dev, sk,
534 filter, count);
535 if (err) {
536 if (count > 1)
537 kfree(filter);
538 goto out_fil;
539 }
540
541 /* remove old filter registrations */
542 raw_disable_filters(sock_net(sk), dev, sk, ro->filter,
543 ro->count);
544 }
545
546 /* remove old filter space */
547 if (ro->count > 1)
548 kfree(ro->filter);
549
550 /* link new filters to the socket */
551 if (count == 1) {
552 /* copy filter data for single filter */
553 ro->dfilter = sfilter;
554 filter = &ro->dfilter;
555 }
556 ro->filter = filter;
557 ro->count = count;
558
559 out_fil:
560 if (dev)
561 dev_put(dev);
562
563 release_sock(sk);
564
565 break;
566
567 case CAN_RAW_ERR_FILTER:
568 if (optlen != sizeof(err_mask))
569 return -EINVAL;
570
571 if (copy_from_user(&err_mask, optval, optlen))
572 return -EFAULT;
573
574 err_mask &= CAN_ERR_MASK;
575
576 lock_sock(sk);
577
578 if (ro->bound && ro->ifindex)
579 dev = dev_get_by_index(sock_net(sk), ro->ifindex);
580
581 /* remove current error mask */
582 if (ro->bound) {
583 /* (try to) register the new err_mask */
584 err = raw_enable_errfilter(sock_net(sk), dev, sk,
585 err_mask);
586
587 if (err)
588 goto out_err;
589
590 /* remove old err_mask registration */
591 raw_disable_errfilter(sock_net(sk), dev, sk,
592 ro->err_mask);
593 }
594
595 /* link new err_mask to the socket */
596 ro->err_mask = err_mask;
597
598 out_err:
599 if (dev)
600 dev_put(dev);
601
602 release_sock(sk);
603
604 break;
605
606 case CAN_RAW_LOOPBACK:
607 if (optlen != sizeof(ro->loopback))
608 return -EINVAL;
609
610 if (copy_from_user(&ro->loopback, optval, optlen))
611 return -EFAULT;
612
613 break;
614
615 case CAN_RAW_RECV_OWN_MSGS:
616 if (optlen != sizeof(ro->recv_own_msgs))
617 return -EINVAL;
618
619 if (copy_from_user(&ro->recv_own_msgs, optval, optlen))
620 return -EFAULT;
621
622 break;
623
624 case CAN_RAW_FD_FRAMES:
625 if (optlen != sizeof(ro->fd_frames))
626 return -EINVAL;
627
628 if (copy_from_user(&ro->fd_frames, optval, optlen))
629 return -EFAULT;
630
631 break;
632
633 case CAN_RAW_JOIN_FILTERS:
634 if (optlen != sizeof(ro->join_filters))
635 return -EINVAL;
636
637 if (copy_from_user(&ro->join_filters, optval, optlen))
638 return -EFAULT;
639
640 break;
641
642 default:
643 return -ENOPROTOOPT;
644 }
645 return err;
646}
647
648static int raw_getsockopt(struct socket *sock, int level, int optname,
649 char __user *optval, int __user *optlen)
650{
651 struct sock *sk = sock->sk;
652 struct raw_sock *ro = raw_sk(sk);
653 int len;
654 void *val;
655 int err = 0;
656
657 if (level != SOL_CAN_RAW)
658 return -EINVAL;
659 if (get_user(len, optlen))
660 return -EFAULT;
661 if (len < 0)
662 return -EINVAL;
663
664 switch (optname) {
665 case CAN_RAW_FILTER:
666 lock_sock(sk);
667 if (ro->count > 0) {
668 int fsize = ro->count * sizeof(struct can_filter);
669
670 if (len > fsize)
671 len = fsize;
672 if (copy_to_user(optval, ro->filter, len))
673 err = -EFAULT;
674 } else {
675 len = 0;
676 }
677 release_sock(sk);
678
679 if (!err)
680 err = put_user(len, optlen);
681 return err;
682
683 case CAN_RAW_ERR_FILTER:
684 if (len > sizeof(can_err_mask_t))
685 len = sizeof(can_err_mask_t);
686 val = &ro->err_mask;
687 break;
688
689 case CAN_RAW_LOOPBACK:
690 if (len > sizeof(int))
691 len = sizeof(int);
692 val = &ro->loopback;
693 break;
694
695 case CAN_RAW_RECV_OWN_MSGS:
696 if (len > sizeof(int))
697 len = sizeof(int);
698 val = &ro->recv_own_msgs;
699 break;
700
701 case CAN_RAW_FD_FRAMES:
702 if (len > sizeof(int))
703 len = sizeof(int);
704 val = &ro->fd_frames;
705 break;
706
707 case CAN_RAW_JOIN_FILTERS:
708 if (len > sizeof(int))
709 len = sizeof(int);
710 val = &ro->join_filters;
711 break;
712
713 default:
714 return -ENOPROTOOPT;
715 }
716
717 if (put_user(len, optlen))
718 return -EFAULT;
719 if (copy_to_user(optval, val, len))
720 return -EFAULT;
721 return 0;
722}
723
724static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
725{
726 struct sock *sk = sock->sk;
727 struct raw_sock *ro = raw_sk(sk);
728 struct sk_buff *skb;
729 struct net_device *dev;
730 int ifindex;
731 int err;
732
733 if (msg->msg_name) {
734 DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name);
735
736 if (msg->msg_namelen < CAN_REQUIRED_SIZE(*addr, can_ifindex))
737 return -EINVAL;
738
739 if (addr->can_family != AF_CAN)
740 return -EINVAL;
741
742 ifindex = addr->can_ifindex;
743 } else {
744 ifindex = ro->ifindex;
745 }
746
747 dev = dev_get_by_index(sock_net(sk), ifindex);
748 if (!dev)
749 return -ENXIO;
750
751 err = -EINVAL;
752 if (ro->fd_frames && dev->mtu == CANFD_MTU) {
753 if (unlikely(size != CANFD_MTU && size != CAN_MTU))
754 goto put_dev;
755 } else {
756 if (unlikely(size != CAN_MTU))
757 goto put_dev;
758 }
759
760 skb = sock_alloc_send_skb(sk, size + sizeof(struct can_skb_priv),
761 msg->msg_flags & MSG_DONTWAIT, &err);
762 if (!skb)
763 goto put_dev;
764
765 can_skb_reserve(skb);
766 can_skb_prv(skb)->ifindex = dev->ifindex;
767 can_skb_prv(skb)->skbcnt = 0;
768
769 err = memcpy_from_msg(skb_put(skb, size), msg, size);
770 if (err < 0)
771 goto free_skb;
772
773 skb_setup_tx_timestamp(skb, sk->sk_tsflags);
774
775 skb->dev = dev;
776 skb->sk = sk;
777 skb->priority = sk->sk_priority;
778
779 err = can_send(skb, ro->loopback);
780
781 dev_put(dev);
782
783 if (err)
784 goto send_failed;
785
786 return size;
787
788free_skb:
789 kfree_skb(skb);
790put_dev:
791 dev_put(dev);
792send_failed:
793 return err;
794}
795
796static int raw_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
797 int flags)
798{
799 struct sock *sk = sock->sk;
800 struct sk_buff *skb;
801 int err = 0;
802 int noblock;
803
804 noblock = flags & MSG_DONTWAIT;
805 flags &= ~MSG_DONTWAIT;
806
807 skb = skb_recv_datagram(sk, flags, noblock, &err);
808 if (!skb)
809 return err;
810
811 if (size < skb->len)
812 msg->msg_flags |= MSG_TRUNC;
813 else
814 size = skb->len;
815
816 err = memcpy_to_msg(msg, skb->data, size);
817 if (err < 0) {
818 skb_free_datagram(sk, skb);
819 return err;
820 }
821
822 sock_recv_ts_and_drops(msg, sk, skb);
823
824 if (msg->msg_name) {
825 __sockaddr_check_size(sizeof(struct sockaddr_can));
826 msg->msg_namelen = sizeof(struct sockaddr_can);
827 memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
828 }
829
830 /* assign the flags that have been recorded in raw_rcv() */
831 msg->msg_flags |= *(raw_flags(skb));
832
833 skb_free_datagram(sk, skb);
834
835 return size;
836}
837
838static int raw_sock_no_ioctlcmd(struct socket *sock, unsigned int cmd,
839 unsigned long arg)
840{
841 /* no ioctls for socket layer -> hand it down to NIC layer */
842 return -ENOIOCTLCMD;
843}
844
845static const struct proto_ops raw_ops = {
846 .family = PF_CAN,
847 .release = raw_release,
848 .bind = raw_bind,
849 .connect = sock_no_connect,
850 .socketpair = sock_no_socketpair,
851 .accept = sock_no_accept,
852 .getname = raw_getname,
853 .poll = datagram_poll,
854 .ioctl = raw_sock_no_ioctlcmd,
855 .gettstamp = sock_gettstamp,
856 .listen = sock_no_listen,
857 .shutdown = sock_no_shutdown,
858 .setsockopt = raw_setsockopt,
859 .getsockopt = raw_getsockopt,
860 .sendmsg = raw_sendmsg,
861 .recvmsg = raw_recvmsg,
862 .mmap = sock_no_mmap,
863 .sendpage = sock_no_sendpage,
864};
865
866static struct proto raw_proto __read_mostly = {
867 .name = "CAN_RAW",
868 .owner = THIS_MODULE,
869 .obj_size = sizeof(struct raw_sock),
870 .init = raw_init,
871};
872
873static const struct can_proto raw_can_proto = {
874 .type = SOCK_RAW,
875 .protocol = CAN_RAW,
876 .ops = &raw_ops,
877 .prot = &raw_proto,
878};
879
880static __init int raw_module_init(void)
881{
882 int err;
883
884 pr_info("can: raw protocol (rev " CAN_RAW_VERSION ")\n");
885
886 err = can_proto_register(&raw_can_proto);
887 if (err < 0)
888 pr_err("can: registration of raw protocol failed\n");
889
890 return err;
891}
892
893static __exit void raw_module_exit(void)
894{
895 can_proto_unregister(&raw_can_proto);
896}
897
898module_init(raw_module_init);
899module_exit(raw_module_exit);