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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
59static __initconst const char banner[] =
60 KERN_INFO "can: raw protocol (rev " CAN_RAW_VERSION ")\n";
61
62MODULE_DESCRIPTION("PF_CAN raw protocol");
63MODULE_LICENSE("Dual BSD/GPL");
64MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>");
65MODULE_ALIAS("can-proto-1");
66
67#define MASK_ALL 0
68
69/*
70 * A raw socket has a list of can_filters attached to it, each receiving
71 * the CAN frames matching that filter. If the filter list is empty,
72 * no CAN frames will be received by the socket. The default after
73 * opening the socket, is to have one filter which receives all frames.
74 * The filter list is allocated dynamically with the exception of the
75 * list containing only one item. This common case is optimized by
76 * storing the single filter in dfilter, to avoid using dynamic memory.
77 */
78
79struct raw_sock {
80 struct sock sk;
81 int bound;
82 int ifindex;
83 struct notifier_block notifier;
84 int loopback;
85 int recv_own_msgs;
86 int fd_frames;
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 /* do not pass non-CAN2.0 frames to a legacy socket */
125 if (!ro->fd_frames && oskb->len != CAN_MTU)
126 return;
127
128 /* clone the given skb to be able to enqueue it into the rcv queue */
129 skb = skb_clone(oskb, GFP_ATOMIC);
130 if (!skb)
131 return;
132
133 /*
134 * Put the datagram to the queue so that raw_recvmsg() can
135 * get it from there. We need to pass the interface index to
136 * raw_recvmsg(). We pass a whole struct sockaddr_can in skb->cb
137 * containing the interface index.
138 */
139
140 BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct sockaddr_can));
141 addr = (struct sockaddr_can *)skb->cb;
142 memset(addr, 0, sizeof(*addr));
143 addr->can_family = AF_CAN;
144 addr->can_ifindex = skb->dev->ifindex;
145
146 /* add CAN specific message flags for raw_recvmsg() */
147 pflags = raw_flags(skb);
148 *pflags = 0;
149 if (oskb->sk)
150 *pflags |= MSG_DONTROUTE;
151 if (oskb->sk == sk)
152 *pflags |= MSG_CONFIRM;
153
154 if (sock_queue_rcv_skb(sk, skb) < 0)
155 kfree_skb(skb);
156}
157
158static int raw_enable_filters(struct net_device *dev, struct sock *sk,
159 struct can_filter *filter, int count)
160{
161 int err = 0;
162 int i;
163
164 for (i = 0; i < count; i++) {
165 err = can_rx_register(dev, filter[i].can_id,
166 filter[i].can_mask,
167 raw_rcv, sk, "raw");
168 if (err) {
169 /* clean up successfully registered filters */
170 while (--i >= 0)
171 can_rx_unregister(dev, filter[i].can_id,
172 filter[i].can_mask,
173 raw_rcv, sk);
174 break;
175 }
176 }
177
178 return err;
179}
180
181static int raw_enable_errfilter(struct net_device *dev, struct sock *sk,
182 can_err_mask_t err_mask)
183{
184 int err = 0;
185
186 if (err_mask)
187 err = can_rx_register(dev, 0, err_mask | CAN_ERR_FLAG,
188 raw_rcv, sk, "raw");
189
190 return err;
191}
192
193static void raw_disable_filters(struct net_device *dev, struct sock *sk,
194 struct can_filter *filter, int count)
195{
196 int i;
197
198 for (i = 0; i < count; i++)
199 can_rx_unregister(dev, filter[i].can_id, filter[i].can_mask,
200 raw_rcv, sk);
201}
202
203static inline void raw_disable_errfilter(struct net_device *dev,
204 struct sock *sk,
205 can_err_mask_t err_mask)
206
207{
208 if (err_mask)
209 can_rx_unregister(dev, 0, err_mask | CAN_ERR_FLAG,
210 raw_rcv, sk);
211}
212
213static inline void raw_disable_allfilters(struct net_device *dev,
214 struct sock *sk)
215{
216 struct raw_sock *ro = raw_sk(sk);
217
218 raw_disable_filters(dev, sk, ro->filter, ro->count);
219 raw_disable_errfilter(dev, sk, ro->err_mask);
220}
221
222static int raw_enable_allfilters(struct net_device *dev, struct sock *sk)
223{
224 struct raw_sock *ro = raw_sk(sk);
225 int err;
226
227 err = raw_enable_filters(dev, sk, ro->filter, ro->count);
228 if (!err) {
229 err = raw_enable_errfilter(dev, sk, ro->err_mask);
230 if (err)
231 raw_disable_filters(dev, sk, ro->filter, ro->count);
232 }
233
234 return err;
235}
236
237static int raw_notifier(struct notifier_block *nb,
238 unsigned long msg, void *ptr)
239{
240 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
241 struct raw_sock *ro = container_of(nb, struct raw_sock, notifier);
242 struct sock *sk = &ro->sk;
243
244 if (!net_eq(dev_net(dev), &init_net))
245 return NOTIFY_DONE;
246
247 if (dev->type != ARPHRD_CAN)
248 return NOTIFY_DONE;
249
250 if (ro->ifindex != dev->ifindex)
251 return NOTIFY_DONE;
252
253 switch (msg) {
254
255 case NETDEV_UNREGISTER:
256 lock_sock(sk);
257 /* remove current filters & unregister */
258 if (ro->bound)
259 raw_disable_allfilters(dev, sk);
260
261 if (ro->count > 1)
262 kfree(ro->filter);
263
264 ro->ifindex = 0;
265 ro->bound = 0;
266 ro->count = 0;
267 release_sock(sk);
268
269 sk->sk_err = ENODEV;
270 if (!sock_flag(sk, SOCK_DEAD))
271 sk->sk_error_report(sk);
272 break;
273
274 case NETDEV_DOWN:
275 sk->sk_err = ENETDOWN;
276 if (!sock_flag(sk, SOCK_DEAD))
277 sk->sk_error_report(sk);
278 break;
279 }
280
281 return NOTIFY_DONE;
282}
283
284static int raw_init(struct sock *sk)
285{
286 struct raw_sock *ro = raw_sk(sk);
287
288 ro->bound = 0;
289 ro->ifindex = 0;
290
291 /* set default filter to single entry dfilter */
292 ro->dfilter.can_id = 0;
293 ro->dfilter.can_mask = MASK_ALL;
294 ro->filter = &ro->dfilter;
295 ro->count = 1;
296
297 /* set default loopback behaviour */
298 ro->loopback = 1;
299 ro->recv_own_msgs = 0;
300 ro->fd_frames = 0;
301
302 /* set notifier */
303 ro->notifier.notifier_call = raw_notifier;
304
305 register_netdevice_notifier(&ro->notifier);
306
307 return 0;
308}
309
310static int raw_release(struct socket *sock)
311{
312 struct sock *sk = sock->sk;
313 struct raw_sock *ro;
314
315 if (!sk)
316 return 0;
317
318 ro = raw_sk(sk);
319
320 unregister_netdevice_notifier(&ro->notifier);
321
322 lock_sock(sk);
323
324 /* remove current filters & unregister */
325 if (ro->bound) {
326 if (ro->ifindex) {
327 struct net_device *dev;
328
329 dev = dev_get_by_index(&init_net, ro->ifindex);
330 if (dev) {
331 raw_disable_allfilters(dev, sk);
332 dev_put(dev);
333 }
334 } else
335 raw_disable_allfilters(NULL, sk);
336 }
337
338 if (ro->count > 1)
339 kfree(ro->filter);
340
341 ro->ifindex = 0;
342 ro->bound = 0;
343 ro->count = 0;
344
345 sock_orphan(sk);
346 sock->sk = NULL;
347
348 release_sock(sk);
349 sock_put(sk);
350
351 return 0;
352}
353
354static int raw_bind(struct socket *sock, struct sockaddr *uaddr, int len)
355{
356 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
357 struct sock *sk = sock->sk;
358 struct raw_sock *ro = raw_sk(sk);
359 int ifindex;
360 int err = 0;
361 int notify_enetdown = 0;
362
363 if (len < sizeof(*addr))
364 return -EINVAL;
365
366 lock_sock(sk);
367
368 if (ro->bound && addr->can_ifindex == ro->ifindex)
369 goto out;
370
371 if (addr->can_ifindex) {
372 struct net_device *dev;
373
374 dev = dev_get_by_index(&init_net, addr->can_ifindex);
375 if (!dev) {
376 err = -ENODEV;
377 goto out;
378 }
379 if (dev->type != ARPHRD_CAN) {
380 dev_put(dev);
381 err = -ENODEV;
382 goto out;
383 }
384 if (!(dev->flags & IFF_UP))
385 notify_enetdown = 1;
386
387 ifindex = dev->ifindex;
388
389 /* filters set by default/setsockopt */
390 err = raw_enable_allfilters(dev, sk);
391 dev_put(dev);
392 } else {
393 ifindex = 0;
394
395 /* filters set by default/setsockopt */
396 err = raw_enable_allfilters(NULL, sk);
397 }
398
399 if (!err) {
400 if (ro->bound) {
401 /* unregister old filters */
402 if (ro->ifindex) {
403 struct net_device *dev;
404
405 dev = dev_get_by_index(&init_net, ro->ifindex);
406 if (dev) {
407 raw_disable_allfilters(dev, sk);
408 dev_put(dev);
409 }
410 } else
411 raw_disable_allfilters(NULL, sk);
412 }
413 ro->ifindex = ifindex;
414 ro->bound = 1;
415 }
416
417 out:
418 release_sock(sk);
419
420 if (notify_enetdown) {
421 sk->sk_err = ENETDOWN;
422 if (!sock_flag(sk, SOCK_DEAD))
423 sk->sk_error_report(sk);
424 }
425
426 return err;
427}
428
429static int raw_getname(struct socket *sock, struct sockaddr *uaddr,
430 int *len, int peer)
431{
432 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
433 struct sock *sk = sock->sk;
434 struct raw_sock *ro = raw_sk(sk);
435
436 if (peer)
437 return -EOPNOTSUPP;
438
439 memset(addr, 0, sizeof(*addr));
440 addr->can_family = AF_CAN;
441 addr->can_ifindex = ro->ifindex;
442
443 *len = sizeof(*addr);
444
445 return 0;
446}
447
448static int raw_setsockopt(struct socket *sock, int level, int optname,
449 char __user *optval, unsigned int optlen)
450{
451 struct sock *sk = sock->sk;
452 struct raw_sock *ro = raw_sk(sk);
453 struct can_filter *filter = NULL; /* dyn. alloc'ed filters */
454 struct can_filter sfilter; /* single filter */
455 struct net_device *dev = NULL;
456 can_err_mask_t err_mask = 0;
457 int count = 0;
458 int err = 0;
459
460 if (level != SOL_CAN_RAW)
461 return -EINVAL;
462
463 switch (optname) {
464
465 case CAN_RAW_FILTER:
466 if (optlen % sizeof(struct can_filter) != 0)
467 return -EINVAL;
468
469 count = optlen / sizeof(struct can_filter);
470
471 if (count > 1) {
472 /* filter does not fit into dfilter => alloc space */
473 filter = memdup_user(optval, optlen);
474 if (IS_ERR(filter))
475 return PTR_ERR(filter);
476 } else if (count == 1) {
477 if (copy_from_user(&sfilter, optval, sizeof(sfilter)))
478 return -EFAULT;
479 }
480
481 lock_sock(sk);
482
483 if (ro->bound && ro->ifindex)
484 dev = dev_get_by_index(&init_net, ro->ifindex);
485
486 if (ro->bound) {
487 /* (try to) register the new filters */
488 if (count == 1)
489 err = raw_enable_filters(dev, sk, &sfilter, 1);
490 else
491 err = raw_enable_filters(dev, sk, filter,
492 count);
493 if (err) {
494 if (count > 1)
495 kfree(filter);
496 goto out_fil;
497 }
498
499 /* remove old filter registrations */
500 raw_disable_filters(dev, sk, ro->filter, ro->count);
501 }
502
503 /* remove old filter space */
504 if (ro->count > 1)
505 kfree(ro->filter);
506
507 /* link new filters to the socket */
508 if (count == 1) {
509 /* copy filter data for single filter */
510 ro->dfilter = sfilter;
511 filter = &ro->dfilter;
512 }
513 ro->filter = filter;
514 ro->count = count;
515
516 out_fil:
517 if (dev)
518 dev_put(dev);
519
520 release_sock(sk);
521
522 break;
523
524 case CAN_RAW_ERR_FILTER:
525 if (optlen != sizeof(err_mask))
526 return -EINVAL;
527
528 if (copy_from_user(&err_mask, optval, optlen))
529 return -EFAULT;
530
531 err_mask &= CAN_ERR_MASK;
532
533 lock_sock(sk);
534
535 if (ro->bound && ro->ifindex)
536 dev = dev_get_by_index(&init_net, ro->ifindex);
537
538 /* remove current error mask */
539 if (ro->bound) {
540 /* (try to) register the new err_mask */
541 err = raw_enable_errfilter(dev, sk, err_mask);
542
543 if (err)
544 goto out_err;
545
546 /* remove old err_mask registration */
547 raw_disable_errfilter(dev, sk, ro->err_mask);
548 }
549
550 /* link new err_mask to the socket */
551 ro->err_mask = err_mask;
552
553 out_err:
554 if (dev)
555 dev_put(dev);
556
557 release_sock(sk);
558
559 break;
560
561 case CAN_RAW_LOOPBACK:
562 if (optlen != sizeof(ro->loopback))
563 return -EINVAL;
564
565 if (copy_from_user(&ro->loopback, optval, optlen))
566 return -EFAULT;
567
568 break;
569
570 case CAN_RAW_RECV_OWN_MSGS:
571 if (optlen != sizeof(ro->recv_own_msgs))
572 return -EINVAL;
573
574 if (copy_from_user(&ro->recv_own_msgs, optval, optlen))
575 return -EFAULT;
576
577 break;
578
579 case CAN_RAW_FD_FRAMES:
580 if (optlen != sizeof(ro->fd_frames))
581 return -EINVAL;
582
583 if (copy_from_user(&ro->fd_frames, optval, optlen))
584 return -EFAULT;
585
586 break;
587
588 default:
589 return -ENOPROTOOPT;
590 }
591 return err;
592}
593
594static int raw_getsockopt(struct socket *sock, int level, int optname,
595 char __user *optval, int __user *optlen)
596{
597 struct sock *sk = sock->sk;
598 struct raw_sock *ro = raw_sk(sk);
599 int len;
600 void *val;
601 int err = 0;
602
603 if (level != SOL_CAN_RAW)
604 return -EINVAL;
605 if (get_user(len, optlen))
606 return -EFAULT;
607 if (len < 0)
608 return -EINVAL;
609
610 switch (optname) {
611
612 case CAN_RAW_FILTER:
613 lock_sock(sk);
614 if (ro->count > 0) {
615 int fsize = ro->count * sizeof(struct can_filter);
616 if (len > fsize)
617 len = fsize;
618 if (copy_to_user(optval, ro->filter, len))
619 err = -EFAULT;
620 } else
621 len = 0;
622 release_sock(sk);
623
624 if (!err)
625 err = put_user(len, optlen);
626 return err;
627
628 case CAN_RAW_ERR_FILTER:
629 if (len > sizeof(can_err_mask_t))
630 len = sizeof(can_err_mask_t);
631 val = &ro->err_mask;
632 break;
633
634 case CAN_RAW_LOOPBACK:
635 if (len > sizeof(int))
636 len = sizeof(int);
637 val = &ro->loopback;
638 break;
639
640 case CAN_RAW_RECV_OWN_MSGS:
641 if (len > sizeof(int))
642 len = sizeof(int);
643 val = &ro->recv_own_msgs;
644 break;
645
646 case CAN_RAW_FD_FRAMES:
647 if (len > sizeof(int))
648 len = sizeof(int);
649 val = &ro->fd_frames;
650 break;
651
652 default:
653 return -ENOPROTOOPT;
654 }
655
656 if (put_user(len, optlen))
657 return -EFAULT;
658 if (copy_to_user(optval, val, len))
659 return -EFAULT;
660 return 0;
661}
662
663static int raw_sendmsg(struct kiocb *iocb, struct socket *sock,
664 struct msghdr *msg, size_t size)
665{
666 struct sock *sk = sock->sk;
667 struct raw_sock *ro = raw_sk(sk);
668 struct sk_buff *skb;
669 struct net_device *dev;
670 int ifindex;
671 int err;
672
673 if (msg->msg_name) {
674 DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name);
675
676 if (msg->msg_namelen < sizeof(*addr))
677 return -EINVAL;
678
679 if (addr->can_family != AF_CAN)
680 return -EINVAL;
681
682 ifindex = addr->can_ifindex;
683 } else
684 ifindex = ro->ifindex;
685
686 if (ro->fd_frames) {
687 if (unlikely(size != CANFD_MTU && size != CAN_MTU))
688 return -EINVAL;
689 } else {
690 if (unlikely(size != CAN_MTU))
691 return -EINVAL;
692 }
693
694 dev = dev_get_by_index(&init_net, ifindex);
695 if (!dev)
696 return -ENXIO;
697
698 skb = sock_alloc_send_skb(sk, size + sizeof(struct can_skb_priv),
699 msg->msg_flags & MSG_DONTWAIT, &err);
700 if (!skb)
701 goto put_dev;
702
703 can_skb_reserve(skb);
704 can_skb_prv(skb)->ifindex = dev->ifindex;
705
706 err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
707 if (err < 0)
708 goto free_skb;
709
710 sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
711
712 skb->dev = dev;
713 skb->sk = sk;
714 skb->priority = sk->sk_priority;
715
716 err = can_send(skb, ro->loopback);
717
718 dev_put(dev);
719
720 if (err)
721 goto send_failed;
722
723 return size;
724
725free_skb:
726 kfree_skb(skb);
727put_dev:
728 dev_put(dev);
729send_failed:
730 return err;
731}
732
733static int raw_recvmsg(struct kiocb *iocb, struct socket *sock,
734 struct msghdr *msg, size_t size, int flags)
735{
736 struct sock *sk = sock->sk;
737 struct sk_buff *skb;
738 int err = 0;
739 int noblock;
740
741 noblock = flags & MSG_DONTWAIT;
742 flags &= ~MSG_DONTWAIT;
743
744 skb = skb_recv_datagram(sk, flags, noblock, &err);
745 if (!skb)
746 return err;
747
748 if (size < skb->len)
749 msg->msg_flags |= MSG_TRUNC;
750 else
751 size = skb->len;
752
753 err = memcpy_toiovec(msg->msg_iov, skb->data, size);
754 if (err < 0) {
755 skb_free_datagram(sk, skb);
756 return err;
757 }
758
759 sock_recv_ts_and_drops(msg, sk, skb);
760
761 if (msg->msg_name) {
762 __sockaddr_check_size(sizeof(struct sockaddr_can));
763 msg->msg_namelen = sizeof(struct sockaddr_can);
764 memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
765 }
766
767 /* assign the flags that have been recorded in raw_rcv() */
768 msg->msg_flags |= *(raw_flags(skb));
769
770 skb_free_datagram(sk, skb);
771
772 return size;
773}
774
775static const struct proto_ops raw_ops = {
776 .family = PF_CAN,
777 .release = raw_release,
778 .bind = raw_bind,
779 .connect = sock_no_connect,
780 .socketpair = sock_no_socketpair,
781 .accept = sock_no_accept,
782 .getname = raw_getname,
783 .poll = datagram_poll,
784 .ioctl = can_ioctl, /* use can_ioctl() from af_can.c */
785 .listen = sock_no_listen,
786 .shutdown = sock_no_shutdown,
787 .setsockopt = raw_setsockopt,
788 .getsockopt = raw_getsockopt,
789 .sendmsg = raw_sendmsg,
790 .recvmsg = raw_recvmsg,
791 .mmap = sock_no_mmap,
792 .sendpage = sock_no_sendpage,
793};
794
795static struct proto raw_proto __read_mostly = {
796 .name = "CAN_RAW",
797 .owner = THIS_MODULE,
798 .obj_size = sizeof(struct raw_sock),
799 .init = raw_init,
800};
801
802static const struct can_proto raw_can_proto = {
803 .type = SOCK_RAW,
804 .protocol = CAN_RAW,
805 .ops = &raw_ops,
806 .prot = &raw_proto,
807};
808
809static __init int raw_module_init(void)
810{
811 int err;
812
813 printk(banner);
814
815 err = can_proto_register(&raw_can_proto);
816 if (err < 0)
817 printk(KERN_ERR "can: registration of raw protocol failed\n");
818
819 return err;
820}
821
822static __exit void raw_module_exit(void)
823{
824 can_proto_unregister(&raw_can_proto);
825}
826
827module_init(raw_module_init);
828module_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 */
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");
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");
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 count = optlen / sizeof(struct can_filter);
503
504 if (count > 1) {
505 /* filter does not fit into dfilter => alloc space */
506 filter = memdup_user(optval, optlen);
507 if (IS_ERR(filter))
508 return PTR_ERR(filter);
509 } else if (count == 1) {
510 if (copy_from_user(&sfilter, optval, sizeof(sfilter)))
511 return -EFAULT;
512 }
513
514 lock_sock(sk);
515
516 if (ro->bound && ro->ifindex)
517 dev = dev_get_by_index(&init_net, ro->ifindex);
518
519 if (ro->bound) {
520 /* (try to) register the new filters */
521 if (count == 1)
522 err = raw_enable_filters(dev, sk, &sfilter, 1);
523 else
524 err = raw_enable_filters(dev, sk, filter,
525 count);
526 if (err) {
527 if (count > 1)
528 kfree(filter);
529 goto out_fil;
530 }
531
532 /* remove old filter registrations */
533 raw_disable_filters(dev, sk, ro->filter, ro->count);
534 }
535
536 /* remove old filter space */
537 if (ro->count > 1)
538 kfree(ro->filter);
539
540 /* link new filters to the socket */
541 if (count == 1) {
542 /* copy filter data for single filter */
543 ro->dfilter = sfilter;
544 filter = &ro->dfilter;
545 }
546 ro->filter = filter;
547 ro->count = count;
548
549 out_fil:
550 if (dev)
551 dev_put(dev);
552
553 release_sock(sk);
554
555 break;
556
557 case CAN_RAW_ERR_FILTER:
558 if (optlen != sizeof(err_mask))
559 return -EINVAL;
560
561 if (copy_from_user(&err_mask, optval, optlen))
562 return -EFAULT;
563
564 err_mask &= CAN_ERR_MASK;
565
566 lock_sock(sk);
567
568 if (ro->bound && ro->ifindex)
569 dev = dev_get_by_index(&init_net, ro->ifindex);
570
571 /* remove current error mask */
572 if (ro->bound) {
573 /* (try to) register the new err_mask */
574 err = raw_enable_errfilter(dev, sk, err_mask);
575
576 if (err)
577 goto out_err;
578
579 /* remove old err_mask registration */
580 raw_disable_errfilter(dev, sk, ro->err_mask);
581 }
582
583 /* link new err_mask to the socket */
584 ro->err_mask = err_mask;
585
586 out_err:
587 if (dev)
588 dev_put(dev);
589
590 release_sock(sk);
591
592 break;
593
594 case CAN_RAW_LOOPBACK:
595 if (optlen != sizeof(ro->loopback))
596 return -EINVAL;
597
598 if (copy_from_user(&ro->loopback, optval, optlen))
599 return -EFAULT;
600
601 break;
602
603 case CAN_RAW_RECV_OWN_MSGS:
604 if (optlen != sizeof(ro->recv_own_msgs))
605 return -EINVAL;
606
607 if (copy_from_user(&ro->recv_own_msgs, optval, optlen))
608 return -EFAULT;
609
610 break;
611
612 case CAN_RAW_FD_FRAMES:
613 if (optlen != sizeof(ro->fd_frames))
614 return -EINVAL;
615
616 if (copy_from_user(&ro->fd_frames, optval, optlen))
617 return -EFAULT;
618
619 break;
620
621 case CAN_RAW_JOIN_FILTERS:
622 if (optlen != sizeof(ro->join_filters))
623 return -EINVAL;
624
625 if (copy_from_user(&ro->join_filters, optval, optlen))
626 return -EFAULT;
627
628 break;
629
630 default:
631 return -ENOPROTOOPT;
632 }
633 return err;
634}
635
636static int raw_getsockopt(struct socket *sock, int level, int optname,
637 char __user *optval, int __user *optlen)
638{
639 struct sock *sk = sock->sk;
640 struct raw_sock *ro = raw_sk(sk);
641 int len;
642 void *val;
643 int err = 0;
644
645 if (level != SOL_CAN_RAW)
646 return -EINVAL;
647 if (get_user(len, optlen))
648 return -EFAULT;
649 if (len < 0)
650 return -EINVAL;
651
652 switch (optname) {
653
654 case CAN_RAW_FILTER:
655 lock_sock(sk);
656 if (ro->count > 0) {
657 int fsize = ro->count * sizeof(struct can_filter);
658 if (len > fsize)
659 len = fsize;
660 if (copy_to_user(optval, ro->filter, len))
661 err = -EFAULT;
662 } else
663 len = 0;
664 release_sock(sk);
665
666 if (!err)
667 err = put_user(len, optlen);
668 return err;
669
670 case CAN_RAW_ERR_FILTER:
671 if (len > sizeof(can_err_mask_t))
672 len = sizeof(can_err_mask_t);
673 val = &ro->err_mask;
674 break;
675
676 case CAN_RAW_LOOPBACK:
677 if (len > sizeof(int))
678 len = sizeof(int);
679 val = &ro->loopback;
680 break;
681
682 case CAN_RAW_RECV_OWN_MSGS:
683 if (len > sizeof(int))
684 len = sizeof(int);
685 val = &ro->recv_own_msgs;
686 break;
687
688 case CAN_RAW_FD_FRAMES:
689 if (len > sizeof(int))
690 len = sizeof(int);
691 val = &ro->fd_frames;
692 break;
693
694 case CAN_RAW_JOIN_FILTERS:
695 if (len > sizeof(int))
696 len = sizeof(int);
697 val = &ro->join_filters;
698 break;
699
700 default:
701 return -ENOPROTOOPT;
702 }
703
704 if (put_user(len, optlen))
705 return -EFAULT;
706 if (copy_to_user(optval, val, len))
707 return -EFAULT;
708 return 0;
709}
710
711static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
712{
713 struct sock *sk = sock->sk;
714 struct raw_sock *ro = raw_sk(sk);
715 struct sk_buff *skb;
716 struct net_device *dev;
717 int ifindex;
718 int err;
719
720 if (msg->msg_name) {
721 DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name);
722
723 if (msg->msg_namelen < sizeof(*addr))
724 return -EINVAL;
725
726 if (addr->can_family != AF_CAN)
727 return -EINVAL;
728
729 ifindex = addr->can_ifindex;
730 } else
731 ifindex = ro->ifindex;
732
733 if (ro->fd_frames) {
734 if (unlikely(size != CANFD_MTU && size != CAN_MTU))
735 return -EINVAL;
736 } else {
737 if (unlikely(size != CAN_MTU))
738 return -EINVAL;
739 }
740
741 dev = dev_get_by_index(&init_net, ifindex);
742 if (!dev)
743 return -ENXIO;
744
745 skb = sock_alloc_send_skb(sk, size + sizeof(struct can_skb_priv),
746 msg->msg_flags & MSG_DONTWAIT, &err);
747 if (!skb)
748 goto put_dev;
749
750 can_skb_reserve(skb);
751 can_skb_prv(skb)->ifindex = dev->ifindex;
752 can_skb_prv(skb)->skbcnt = 0;
753
754 err = memcpy_from_msg(skb_put(skb, size), msg, size);
755 if (err < 0)
756 goto free_skb;
757
758 sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
759
760 skb->dev = dev;
761 skb->sk = sk;
762 skb->priority = sk->sk_priority;
763
764 err = can_send(skb, ro->loopback);
765
766 dev_put(dev);
767
768 if (err)
769 goto send_failed;
770
771 return size;
772
773free_skb:
774 kfree_skb(skb);
775put_dev:
776 dev_put(dev);
777send_failed:
778 return err;
779}
780
781static int raw_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
782 int flags)
783{
784 struct sock *sk = sock->sk;
785 struct sk_buff *skb;
786 int err = 0;
787 int noblock;
788
789 noblock = flags & MSG_DONTWAIT;
790 flags &= ~MSG_DONTWAIT;
791
792 skb = skb_recv_datagram(sk, flags, noblock, &err);
793 if (!skb)
794 return err;
795
796 if (size < skb->len)
797 msg->msg_flags |= MSG_TRUNC;
798 else
799 size = skb->len;
800
801 err = memcpy_to_msg(msg, skb->data, size);
802 if (err < 0) {
803 skb_free_datagram(sk, skb);
804 return err;
805 }
806
807 sock_recv_ts_and_drops(msg, sk, skb);
808
809 if (msg->msg_name) {
810 __sockaddr_check_size(sizeof(struct sockaddr_can));
811 msg->msg_namelen = sizeof(struct sockaddr_can);
812 memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
813 }
814
815 /* assign the flags that have been recorded in raw_rcv() */
816 msg->msg_flags |= *(raw_flags(skb));
817
818 skb_free_datagram(sk, skb);
819
820 return size;
821}
822
823static const struct proto_ops raw_ops = {
824 .family = PF_CAN,
825 .release = raw_release,
826 .bind = raw_bind,
827 .connect = sock_no_connect,
828 .socketpair = sock_no_socketpair,
829 .accept = sock_no_accept,
830 .getname = raw_getname,
831 .poll = datagram_poll,
832 .ioctl = can_ioctl, /* use can_ioctl() from af_can.c */
833 .listen = sock_no_listen,
834 .shutdown = sock_no_shutdown,
835 .setsockopt = raw_setsockopt,
836 .getsockopt = raw_getsockopt,
837 .sendmsg = raw_sendmsg,
838 .recvmsg = raw_recvmsg,
839 .mmap = sock_no_mmap,
840 .sendpage = sock_no_sendpage,
841};
842
843static struct proto raw_proto __read_mostly = {
844 .name = "CAN_RAW",
845 .owner = THIS_MODULE,
846 .obj_size = sizeof(struct raw_sock),
847 .init = raw_init,
848};
849
850static const struct can_proto raw_can_proto = {
851 .type = SOCK_RAW,
852 .protocol = CAN_RAW,
853 .ops = &raw_ops,
854 .prot = &raw_proto,
855};
856
857static __init int raw_module_init(void)
858{
859 int err;
860
861 pr_info("can: raw protocol (rev " CAN_RAW_VERSION ")\n");
862
863 err = can_proto_register(&raw_can_proto);
864 if (err < 0)
865 printk(KERN_ERR "can: registration of raw protocol failed\n");
866
867 return err;
868}
869
870static __exit void raw_module_exit(void)
871{
872 can_proto_unregister(&raw_can_proto);
873}
874
875module_init(raw_module_init);
876module_exit(raw_module_exit);