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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/*
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 * Send feedback to <socketcan-users@lists.berlios.de>
41 *
42 */
43
44#include <linux/module.h>
45#include <linux/init.h>
46#include <linux/uio.h>
47#include <linux/net.h>
48#include <linux/slab.h>
49#include <linux/netdevice.h>
50#include <linux/socket.h>
51#include <linux/if_arp.h>
52#include <linux/skbuff.h>
53#include <linux/can.h>
54#include <linux/can/core.h>
55#include <linux/can/raw.h>
56#include <net/sock.h>
57#include <net/net_namespace.h>
58
59#define CAN_RAW_VERSION CAN_VERSION
60static __initdata const char banner[] =
61 KERN_INFO "can: raw protocol (rev " CAN_RAW_VERSION ")\n";
62
63MODULE_DESCRIPTION("PF_CAN raw protocol");
64MODULE_LICENSE("Dual BSD/GPL");
65MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>");
66MODULE_ALIAS("can-proto-1");
67
68#define MASK_ALL 0
69
70/*
71 * A raw socket has a list of can_filters attached to it, each receiving
72 * the CAN frames matching that filter. If the filter list is empty,
73 * no CAN frames will be received by the socket. The default after
74 * opening the socket, is to have one filter which receives all frames.
75 * The filter list is allocated dynamically with the exception of the
76 * list containing only one item. This common case is optimized by
77 * storing the single filter in dfilter, to avoid using dynamic memory.
78 */
79
80struct raw_sock {
81 struct sock sk;
82 int bound;
83 int ifindex;
84 struct notifier_block notifier;
85 int loopback;
86 int recv_own_msgs;
87 int count; /* number of active filters */
88 struct can_filter dfilter; /* default/single filter */
89 struct can_filter *filter; /* pointer to filter(s) */
90 can_err_mask_t err_mask;
91};
92
93/*
94 * Return pointer to store the extra msg flags for raw_recvmsg().
95 * We use the space of one unsigned int beyond the 'struct sockaddr_can'
96 * in skb->cb.
97 */
98static inline unsigned int *raw_flags(struct sk_buff *skb)
99{
100 BUILD_BUG_ON(sizeof(skb->cb) <= (sizeof(struct sockaddr_can) +
101 sizeof(unsigned int)));
102
103 /* return pointer after struct sockaddr_can */
104 return (unsigned int *)(&((struct sockaddr_can *)skb->cb)[1]);
105}
106
107static inline struct raw_sock *raw_sk(const struct sock *sk)
108{
109 return (struct raw_sock *)sk;
110}
111
112static void raw_rcv(struct sk_buff *oskb, void *data)
113{
114 struct sock *sk = (struct sock *)data;
115 struct raw_sock *ro = raw_sk(sk);
116 struct sockaddr_can *addr;
117 struct sk_buff *skb;
118 unsigned int *pflags;
119
120 /* check the received tx sock reference */
121 if (!ro->recv_own_msgs && oskb->sk == sk)
122 return;
123
124 /* clone the given skb to be able to enqueue it into the rcv queue */
125 skb = skb_clone(oskb, GFP_ATOMIC);
126 if (!skb)
127 return;
128
129 /*
130 * Put the datagram to the queue so that raw_recvmsg() can
131 * get it from there. We need to pass the interface index to
132 * raw_recvmsg(). We pass a whole struct sockaddr_can in skb->cb
133 * containing the interface index.
134 */
135
136 BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct sockaddr_can));
137 addr = (struct sockaddr_can *)skb->cb;
138 memset(addr, 0, sizeof(*addr));
139 addr->can_family = AF_CAN;
140 addr->can_ifindex = skb->dev->ifindex;
141
142 /* add CAN specific message flags for raw_recvmsg() */
143 pflags = raw_flags(skb);
144 *pflags = 0;
145 if (oskb->sk)
146 *pflags |= MSG_DONTROUTE;
147 if (oskb->sk == sk)
148 *pflags |= MSG_CONFIRM;
149
150 if (sock_queue_rcv_skb(sk, skb) < 0)
151 kfree_skb(skb);
152}
153
154static int raw_enable_filters(struct net_device *dev, struct sock *sk,
155 struct can_filter *filter, int count)
156{
157 int err = 0;
158 int i;
159
160 for (i = 0; i < count; i++) {
161 err = can_rx_register(dev, filter[i].can_id,
162 filter[i].can_mask,
163 raw_rcv, sk, "raw");
164 if (err) {
165 /* clean up successfully registered filters */
166 while (--i >= 0)
167 can_rx_unregister(dev, filter[i].can_id,
168 filter[i].can_mask,
169 raw_rcv, sk);
170 break;
171 }
172 }
173
174 return err;
175}
176
177static int raw_enable_errfilter(struct net_device *dev, struct sock *sk,
178 can_err_mask_t err_mask)
179{
180 int err = 0;
181
182 if (err_mask)
183 err = can_rx_register(dev, 0, err_mask | CAN_ERR_FLAG,
184 raw_rcv, sk, "raw");
185
186 return err;
187}
188
189static void raw_disable_filters(struct net_device *dev, struct sock *sk,
190 struct can_filter *filter, int count)
191{
192 int i;
193
194 for (i = 0; i < count; i++)
195 can_rx_unregister(dev, filter[i].can_id, filter[i].can_mask,
196 raw_rcv, sk);
197}
198
199static inline void raw_disable_errfilter(struct net_device *dev,
200 struct sock *sk,
201 can_err_mask_t err_mask)
202
203{
204 if (err_mask)
205 can_rx_unregister(dev, 0, err_mask | CAN_ERR_FLAG,
206 raw_rcv, sk);
207}
208
209static inline void raw_disable_allfilters(struct net_device *dev,
210 struct sock *sk)
211{
212 struct raw_sock *ro = raw_sk(sk);
213
214 raw_disable_filters(dev, sk, ro->filter, ro->count);
215 raw_disable_errfilter(dev, sk, ro->err_mask);
216}
217
218static int raw_enable_allfilters(struct net_device *dev, struct sock *sk)
219{
220 struct raw_sock *ro = raw_sk(sk);
221 int err;
222
223 err = raw_enable_filters(dev, sk, ro->filter, ro->count);
224 if (!err) {
225 err = raw_enable_errfilter(dev, sk, ro->err_mask);
226 if (err)
227 raw_disable_filters(dev, sk, ro->filter, ro->count);
228 }
229
230 return err;
231}
232
233static int raw_notifier(struct notifier_block *nb,
234 unsigned long msg, void *data)
235{
236 struct net_device *dev = (struct net_device *)data;
237 struct raw_sock *ro = container_of(nb, struct raw_sock, notifier);
238 struct sock *sk = &ro->sk;
239
240 if (!net_eq(dev_net(dev), &init_net))
241 return NOTIFY_DONE;
242
243 if (dev->type != ARPHRD_CAN)
244 return NOTIFY_DONE;
245
246 if (ro->ifindex != dev->ifindex)
247 return NOTIFY_DONE;
248
249 switch (msg) {
250
251 case NETDEV_UNREGISTER:
252 lock_sock(sk);
253 /* remove current filters & unregister */
254 if (ro->bound)
255 raw_disable_allfilters(dev, sk);
256
257 if (ro->count > 1)
258 kfree(ro->filter);
259
260 ro->ifindex = 0;
261 ro->bound = 0;
262 ro->count = 0;
263 release_sock(sk);
264
265 sk->sk_err = ENODEV;
266 if (!sock_flag(sk, SOCK_DEAD))
267 sk->sk_error_report(sk);
268 break;
269
270 case NETDEV_DOWN:
271 sk->sk_err = ENETDOWN;
272 if (!sock_flag(sk, SOCK_DEAD))
273 sk->sk_error_report(sk);
274 break;
275 }
276
277 return NOTIFY_DONE;
278}
279
280static int raw_init(struct sock *sk)
281{
282 struct raw_sock *ro = raw_sk(sk);
283
284 ro->bound = 0;
285 ro->ifindex = 0;
286
287 /* set default filter to single entry dfilter */
288 ro->dfilter.can_id = 0;
289 ro->dfilter.can_mask = MASK_ALL;
290 ro->filter = &ro->dfilter;
291 ro->count = 1;
292
293 /* set default loopback behaviour */
294 ro->loopback = 1;
295 ro->recv_own_msgs = 0;
296
297 /* set notifier */
298 ro->notifier.notifier_call = raw_notifier;
299
300 register_netdevice_notifier(&ro->notifier);
301
302 return 0;
303}
304
305static int raw_release(struct socket *sock)
306{
307 struct sock *sk = sock->sk;
308 struct raw_sock *ro;
309
310 if (!sk)
311 return 0;
312
313 ro = raw_sk(sk);
314
315 unregister_netdevice_notifier(&ro->notifier);
316
317 lock_sock(sk);
318
319 /* remove current filters & unregister */
320 if (ro->bound) {
321 if (ro->ifindex) {
322 struct net_device *dev;
323
324 dev = dev_get_by_index(&init_net, ro->ifindex);
325 if (dev) {
326 raw_disable_allfilters(dev, sk);
327 dev_put(dev);
328 }
329 } else
330 raw_disable_allfilters(NULL, sk);
331 }
332
333 if (ro->count > 1)
334 kfree(ro->filter);
335
336 ro->ifindex = 0;
337 ro->bound = 0;
338 ro->count = 0;
339
340 sock_orphan(sk);
341 sock->sk = NULL;
342
343 release_sock(sk);
344 sock_put(sk);
345
346 return 0;
347}
348
349static int raw_bind(struct socket *sock, struct sockaddr *uaddr, int len)
350{
351 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
352 struct sock *sk = sock->sk;
353 struct raw_sock *ro = raw_sk(sk);
354 int ifindex;
355 int err = 0;
356 int notify_enetdown = 0;
357
358 if (len < sizeof(*addr))
359 return -EINVAL;
360
361 lock_sock(sk);
362
363 if (ro->bound && addr->can_ifindex == ro->ifindex)
364 goto out;
365
366 if (addr->can_ifindex) {
367 struct net_device *dev;
368
369 dev = dev_get_by_index(&init_net, addr->can_ifindex);
370 if (!dev) {
371 err = -ENODEV;
372 goto out;
373 }
374 if (dev->type != ARPHRD_CAN) {
375 dev_put(dev);
376 err = -ENODEV;
377 goto out;
378 }
379 if (!(dev->flags & IFF_UP))
380 notify_enetdown = 1;
381
382 ifindex = dev->ifindex;
383
384 /* filters set by default/setsockopt */
385 err = raw_enable_allfilters(dev, sk);
386 dev_put(dev);
387 } else {
388 ifindex = 0;
389
390 /* filters set by default/setsockopt */
391 err = raw_enable_allfilters(NULL, sk);
392 }
393
394 if (!err) {
395 if (ro->bound) {
396 /* unregister old filters */
397 if (ro->ifindex) {
398 struct net_device *dev;
399
400 dev = dev_get_by_index(&init_net, ro->ifindex);
401 if (dev) {
402 raw_disable_allfilters(dev, sk);
403 dev_put(dev);
404 }
405 } else
406 raw_disable_allfilters(NULL, sk);
407 }
408 ro->ifindex = ifindex;
409 ro->bound = 1;
410 }
411
412 out:
413 release_sock(sk);
414
415 if (notify_enetdown) {
416 sk->sk_err = ENETDOWN;
417 if (!sock_flag(sk, SOCK_DEAD))
418 sk->sk_error_report(sk);
419 }
420
421 return err;
422}
423
424static int raw_getname(struct socket *sock, struct sockaddr *uaddr,
425 int *len, int peer)
426{
427 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
428 struct sock *sk = sock->sk;
429 struct raw_sock *ro = raw_sk(sk);
430
431 if (peer)
432 return -EOPNOTSUPP;
433
434 memset(addr, 0, sizeof(*addr));
435 addr->can_family = AF_CAN;
436 addr->can_ifindex = ro->ifindex;
437
438 *len = sizeof(*addr);
439
440 return 0;
441}
442
443static int raw_setsockopt(struct socket *sock, int level, int optname,
444 char __user *optval, unsigned int optlen)
445{
446 struct sock *sk = sock->sk;
447 struct raw_sock *ro = raw_sk(sk);
448 struct can_filter *filter = NULL; /* dyn. alloc'ed filters */
449 struct can_filter sfilter; /* single filter */
450 struct net_device *dev = NULL;
451 can_err_mask_t err_mask = 0;
452 int count = 0;
453 int err = 0;
454
455 if (level != SOL_CAN_RAW)
456 return -EINVAL;
457
458 switch (optname) {
459
460 case CAN_RAW_FILTER:
461 if (optlen % sizeof(struct can_filter) != 0)
462 return -EINVAL;
463
464 count = optlen / sizeof(struct can_filter);
465
466 if (count > 1) {
467 /* filter does not fit into dfilter => alloc space */
468 filter = memdup_user(optval, optlen);
469 if (IS_ERR(filter))
470 return PTR_ERR(filter);
471 } else if (count == 1) {
472 if (copy_from_user(&sfilter, optval, sizeof(sfilter)))
473 return -EFAULT;
474 }
475
476 lock_sock(sk);
477
478 if (ro->bound && ro->ifindex)
479 dev = dev_get_by_index(&init_net, ro->ifindex);
480
481 if (ro->bound) {
482 /* (try to) register the new filters */
483 if (count == 1)
484 err = raw_enable_filters(dev, sk, &sfilter, 1);
485 else
486 err = raw_enable_filters(dev, sk, filter,
487 count);
488 if (err) {
489 if (count > 1)
490 kfree(filter);
491 goto out_fil;
492 }
493
494 /* remove old filter registrations */
495 raw_disable_filters(dev, sk, ro->filter, ro->count);
496 }
497
498 /* remove old filter space */
499 if (ro->count > 1)
500 kfree(ro->filter);
501
502 /* link new filters to the socket */
503 if (count == 1) {
504 /* copy filter data for single filter */
505 ro->dfilter = sfilter;
506 filter = &ro->dfilter;
507 }
508 ro->filter = filter;
509 ro->count = count;
510
511 out_fil:
512 if (dev)
513 dev_put(dev);
514
515 release_sock(sk);
516
517 break;
518
519 case CAN_RAW_ERR_FILTER:
520 if (optlen != sizeof(err_mask))
521 return -EINVAL;
522
523 if (copy_from_user(&err_mask, optval, optlen))
524 return -EFAULT;
525
526 err_mask &= CAN_ERR_MASK;
527
528 lock_sock(sk);
529
530 if (ro->bound && ro->ifindex)
531 dev = dev_get_by_index(&init_net, ro->ifindex);
532
533 /* remove current error mask */
534 if (ro->bound) {
535 /* (try to) register the new err_mask */
536 err = raw_enable_errfilter(dev, sk, err_mask);
537
538 if (err)
539 goto out_err;
540
541 /* remove old err_mask registration */
542 raw_disable_errfilter(dev, sk, ro->err_mask);
543 }
544
545 /* link new err_mask to the socket */
546 ro->err_mask = err_mask;
547
548 out_err:
549 if (dev)
550 dev_put(dev);
551
552 release_sock(sk);
553
554 break;
555
556 case CAN_RAW_LOOPBACK:
557 if (optlen != sizeof(ro->loopback))
558 return -EINVAL;
559
560 if (copy_from_user(&ro->loopback, optval, optlen))
561 return -EFAULT;
562
563 break;
564
565 case CAN_RAW_RECV_OWN_MSGS:
566 if (optlen != sizeof(ro->recv_own_msgs))
567 return -EINVAL;
568
569 if (copy_from_user(&ro->recv_own_msgs, optval, optlen))
570 return -EFAULT;
571
572 break;
573
574 default:
575 return -ENOPROTOOPT;
576 }
577 return err;
578}
579
580static int raw_getsockopt(struct socket *sock, int level, int optname,
581 char __user *optval, int __user *optlen)
582{
583 struct sock *sk = sock->sk;
584 struct raw_sock *ro = raw_sk(sk);
585 int len;
586 void *val;
587 int err = 0;
588
589 if (level != SOL_CAN_RAW)
590 return -EINVAL;
591 if (get_user(len, optlen))
592 return -EFAULT;
593 if (len < 0)
594 return -EINVAL;
595
596 switch (optname) {
597
598 case CAN_RAW_FILTER:
599 lock_sock(sk);
600 if (ro->count > 0) {
601 int fsize = ro->count * sizeof(struct can_filter);
602 if (len > fsize)
603 len = fsize;
604 if (copy_to_user(optval, ro->filter, len))
605 err = -EFAULT;
606 } else
607 len = 0;
608 release_sock(sk);
609
610 if (!err)
611 err = put_user(len, optlen);
612 return err;
613
614 case CAN_RAW_ERR_FILTER:
615 if (len > sizeof(can_err_mask_t))
616 len = sizeof(can_err_mask_t);
617 val = &ro->err_mask;
618 break;
619
620 case CAN_RAW_LOOPBACK:
621 if (len > sizeof(int))
622 len = sizeof(int);
623 val = &ro->loopback;
624 break;
625
626 case CAN_RAW_RECV_OWN_MSGS:
627 if (len > sizeof(int))
628 len = sizeof(int);
629 val = &ro->recv_own_msgs;
630 break;
631
632 default:
633 return -ENOPROTOOPT;
634 }
635
636 if (put_user(len, optlen))
637 return -EFAULT;
638 if (copy_to_user(optval, val, len))
639 return -EFAULT;
640 return 0;
641}
642
643static int raw_sendmsg(struct kiocb *iocb, struct socket *sock,
644 struct msghdr *msg, size_t size)
645{
646 struct sock *sk = sock->sk;
647 struct raw_sock *ro = raw_sk(sk);
648 struct sk_buff *skb;
649 struct net_device *dev;
650 int ifindex;
651 int err;
652
653 if (msg->msg_name) {
654 struct sockaddr_can *addr =
655 (struct sockaddr_can *)msg->msg_name;
656
657 if (msg->msg_namelen < sizeof(*addr))
658 return -EINVAL;
659
660 if (addr->can_family != AF_CAN)
661 return -EINVAL;
662
663 ifindex = addr->can_ifindex;
664 } else
665 ifindex = ro->ifindex;
666
667 if (size != sizeof(struct can_frame))
668 return -EINVAL;
669
670 dev = dev_get_by_index(&init_net, ifindex);
671 if (!dev)
672 return -ENXIO;
673
674 skb = sock_alloc_send_skb(sk, size, msg->msg_flags & MSG_DONTWAIT,
675 &err);
676 if (!skb)
677 goto put_dev;
678
679 err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
680 if (err < 0)
681 goto free_skb;
682 err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
683 if (err < 0)
684 goto free_skb;
685
686 /* to be able to check the received tx sock reference in raw_rcv() */
687 skb_shinfo(skb)->tx_flags |= SKBTX_DRV_NEEDS_SK_REF;
688
689 skb->dev = dev;
690 skb->sk = sk;
691
692 err = can_send(skb, ro->loopback);
693
694 dev_put(dev);
695
696 if (err)
697 goto send_failed;
698
699 return size;
700
701free_skb:
702 kfree_skb(skb);
703put_dev:
704 dev_put(dev);
705send_failed:
706 return err;
707}
708
709static int raw_recvmsg(struct kiocb *iocb, struct socket *sock,
710 struct msghdr *msg, size_t size, int flags)
711{
712 struct sock *sk = sock->sk;
713 struct sk_buff *skb;
714 int err = 0;
715 int noblock;
716
717 noblock = flags & MSG_DONTWAIT;
718 flags &= ~MSG_DONTWAIT;
719
720 skb = skb_recv_datagram(sk, flags, noblock, &err);
721 if (!skb)
722 return err;
723
724 if (size < skb->len)
725 msg->msg_flags |= MSG_TRUNC;
726 else
727 size = skb->len;
728
729 err = memcpy_toiovec(msg->msg_iov, skb->data, size);
730 if (err < 0) {
731 skb_free_datagram(sk, skb);
732 return err;
733 }
734
735 sock_recv_ts_and_drops(msg, sk, skb);
736
737 if (msg->msg_name) {
738 msg->msg_namelen = sizeof(struct sockaddr_can);
739 memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
740 }
741
742 /* assign the flags that have been recorded in raw_rcv() */
743 msg->msg_flags |= *(raw_flags(skb));
744
745 skb_free_datagram(sk, skb);
746
747 return size;
748}
749
750static const struct proto_ops raw_ops = {
751 .family = PF_CAN,
752 .release = raw_release,
753 .bind = raw_bind,
754 .connect = sock_no_connect,
755 .socketpair = sock_no_socketpair,
756 .accept = sock_no_accept,
757 .getname = raw_getname,
758 .poll = datagram_poll,
759 .ioctl = can_ioctl, /* use can_ioctl() from af_can.c */
760 .listen = sock_no_listen,
761 .shutdown = sock_no_shutdown,
762 .setsockopt = raw_setsockopt,
763 .getsockopt = raw_getsockopt,
764 .sendmsg = raw_sendmsg,
765 .recvmsg = raw_recvmsg,
766 .mmap = sock_no_mmap,
767 .sendpage = sock_no_sendpage,
768};
769
770static struct proto raw_proto __read_mostly = {
771 .name = "CAN_RAW",
772 .owner = THIS_MODULE,
773 .obj_size = sizeof(struct raw_sock),
774 .init = raw_init,
775};
776
777static const struct can_proto raw_can_proto = {
778 .type = SOCK_RAW,
779 .protocol = CAN_RAW,
780 .ops = &raw_ops,
781 .prot = &raw_proto,
782};
783
784static __init int raw_module_init(void)
785{
786 int err;
787
788 printk(banner);
789
790 err = can_proto_register(&raw_can_proto);
791 if (err < 0)
792 printk(KERN_ERR "can: registration of raw protocol failed\n");
793
794 return err;
795}
796
797static __exit void raw_module_exit(void)
798{
799 can_proto_unregister(&raw_can_proto);
800}
801
802module_init(raw_module_init);
803module_exit(raw_module_exit);