Loading...
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// SPDX-License-Identifier: (GPL-2.0 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/dev.h> /* for can_is_canxl_dev_mtu() */
54#include <linux/can/skb.h>
55#include <linux/can/raw.h>
56#include <net/sock.h>
57#include <net/net_namespace.h>
58
59MODULE_DESCRIPTION("PF_CAN raw protocol");
60MODULE_LICENSE("Dual BSD/GPL");
61MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>");
62MODULE_ALIAS("can-proto-1");
63
64#define RAW_MIN_NAMELEN CAN_REQUIRED_SIZE(struct sockaddr_can, can_ifindex)
65
66#define MASK_ALL 0
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 list_head notifier;
88 int loopback;
89 int recv_own_msgs;
90 int fd_frames;
91 int xl_frames;
92 int join_filters;
93 int count; /* number of active filters */
94 struct can_filter dfilter; /* default/single filter */
95 struct can_filter *filter; /* pointer to filter(s) */
96 can_err_mask_t err_mask;
97 struct uniqframe __percpu *uniq;
98};
99
100static LIST_HEAD(raw_notifier_list);
101static DEFINE_SPINLOCK(raw_notifier_lock);
102static struct raw_sock *raw_busy_notifier;
103
104/* Return pointer to store the extra msg flags for raw_recvmsg().
105 * We use the space of one unsigned int beyond the 'struct sockaddr_can'
106 * in skb->cb.
107 */
108static inline unsigned int *raw_flags(struct sk_buff *skb)
109{
110 sock_skb_cb_check_size(sizeof(struct sockaddr_can) +
111 sizeof(unsigned int));
112
113 /* return pointer after struct sockaddr_can */
114 return (unsigned int *)(&((struct sockaddr_can *)skb->cb)[1]);
115}
116
117static inline struct raw_sock *raw_sk(const struct sock *sk)
118{
119 return (struct raw_sock *)sk;
120}
121
122static void raw_rcv(struct sk_buff *oskb, void *data)
123{
124 struct sock *sk = (struct sock *)data;
125 struct raw_sock *ro = raw_sk(sk);
126 struct sockaddr_can *addr;
127 struct sk_buff *skb;
128 unsigned int *pflags;
129
130 /* check the received tx sock reference */
131 if (!ro->recv_own_msgs && oskb->sk == sk)
132 return;
133
134 /* make sure to not pass oversized frames to the socket */
135 if ((!ro->fd_frames && can_is_canfd_skb(oskb)) ||
136 (!ro->xl_frames && can_is_canxl_skb(oskb)))
137 return;
138
139 /* eliminate multiple filter matches for the same skb */
140 if (this_cpu_ptr(ro->uniq)->skb == oskb &&
141 this_cpu_ptr(ro->uniq)->skbcnt == can_skb_prv(oskb)->skbcnt) {
142 if (!ro->join_filters)
143 return;
144
145 this_cpu_inc(ro->uniq->join_rx_count);
146 /* drop frame until all enabled filters matched */
147 if (this_cpu_ptr(ro->uniq)->join_rx_count < ro->count)
148 return;
149 } else {
150 this_cpu_ptr(ro->uniq)->skb = oskb;
151 this_cpu_ptr(ro->uniq)->skbcnt = can_skb_prv(oskb)->skbcnt;
152 this_cpu_ptr(ro->uniq)->join_rx_count = 1;
153 /* drop first frame to check all enabled filters? */
154 if (ro->join_filters && ro->count > 1)
155 return;
156 }
157
158 /* clone the given skb to be able to enqueue it into the rcv queue */
159 skb = skb_clone(oskb, GFP_ATOMIC);
160 if (!skb)
161 return;
162
163 /* Put the datagram to the queue so that raw_recvmsg() can get
164 * it from there. We need to pass the interface index to
165 * raw_recvmsg(). We pass a whole struct sockaddr_can in
166 * skb->cb containing the interface index.
167 */
168
169 sock_skb_cb_check_size(sizeof(struct sockaddr_can));
170 addr = (struct sockaddr_can *)skb->cb;
171 memset(addr, 0, sizeof(*addr));
172 addr->can_family = AF_CAN;
173 addr->can_ifindex = skb->dev->ifindex;
174
175 /* add CAN specific message flags for raw_recvmsg() */
176 pflags = raw_flags(skb);
177 *pflags = 0;
178 if (oskb->sk)
179 *pflags |= MSG_DONTROUTE;
180 if (oskb->sk == sk)
181 *pflags |= MSG_CONFIRM;
182
183 if (sock_queue_rcv_skb(sk, skb) < 0)
184 kfree_skb(skb);
185}
186
187static int raw_enable_filters(struct net *net, struct net_device *dev,
188 struct sock *sk, struct can_filter *filter,
189 int count)
190{
191 int err = 0;
192 int i;
193
194 for (i = 0; i < count; i++) {
195 err = can_rx_register(net, dev, filter[i].can_id,
196 filter[i].can_mask,
197 raw_rcv, sk, "raw", sk);
198 if (err) {
199 /* clean up successfully registered filters */
200 while (--i >= 0)
201 can_rx_unregister(net, dev, filter[i].can_id,
202 filter[i].can_mask,
203 raw_rcv, sk);
204 break;
205 }
206 }
207
208 return err;
209}
210
211static int raw_enable_errfilter(struct net *net, struct net_device *dev,
212 struct sock *sk, can_err_mask_t err_mask)
213{
214 int err = 0;
215
216 if (err_mask)
217 err = can_rx_register(net, dev, 0, err_mask | CAN_ERR_FLAG,
218 raw_rcv, sk, "raw", sk);
219
220 return err;
221}
222
223static void raw_disable_filters(struct net *net, struct net_device *dev,
224 struct sock *sk, struct can_filter *filter,
225 int count)
226{
227 int i;
228
229 for (i = 0; i < count; i++)
230 can_rx_unregister(net, dev, filter[i].can_id,
231 filter[i].can_mask, raw_rcv, sk);
232}
233
234static inline void raw_disable_errfilter(struct net *net,
235 struct net_device *dev,
236 struct sock *sk,
237 can_err_mask_t err_mask)
238
239{
240 if (err_mask)
241 can_rx_unregister(net, dev, 0, err_mask | CAN_ERR_FLAG,
242 raw_rcv, sk);
243}
244
245static inline void raw_disable_allfilters(struct net *net,
246 struct net_device *dev,
247 struct sock *sk)
248{
249 struct raw_sock *ro = raw_sk(sk);
250
251 raw_disable_filters(net, dev, sk, ro->filter, ro->count);
252 raw_disable_errfilter(net, dev, sk, ro->err_mask);
253}
254
255static int raw_enable_allfilters(struct net *net, struct net_device *dev,
256 struct sock *sk)
257{
258 struct raw_sock *ro = raw_sk(sk);
259 int err;
260
261 err = raw_enable_filters(net, dev, sk, ro->filter, ro->count);
262 if (!err) {
263 err = raw_enable_errfilter(net, dev, sk, ro->err_mask);
264 if (err)
265 raw_disable_filters(net, dev, sk, ro->filter,
266 ro->count);
267 }
268
269 return err;
270}
271
272static void raw_notify(struct raw_sock *ro, unsigned long msg,
273 struct net_device *dev)
274{
275 struct sock *sk = &ro->sk;
276
277 if (!net_eq(dev_net(dev), sock_net(sk)))
278 return;
279
280 if (ro->ifindex != dev->ifindex)
281 return;
282
283 switch (msg) {
284 case NETDEV_UNREGISTER:
285 lock_sock(sk);
286 /* remove current filters & unregister */
287 if (ro->bound)
288 raw_disable_allfilters(dev_net(dev), dev, sk);
289
290 if (ro->count > 1)
291 kfree(ro->filter);
292
293 ro->ifindex = 0;
294 ro->bound = 0;
295 ro->count = 0;
296 release_sock(sk);
297
298 sk->sk_err = ENODEV;
299 if (!sock_flag(sk, SOCK_DEAD))
300 sk_error_report(sk);
301 break;
302
303 case NETDEV_DOWN:
304 sk->sk_err = ENETDOWN;
305 if (!sock_flag(sk, SOCK_DEAD))
306 sk_error_report(sk);
307 break;
308 }
309}
310
311static int raw_notifier(struct notifier_block *nb, unsigned long msg,
312 void *ptr)
313{
314 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
315
316 if (dev->type != ARPHRD_CAN)
317 return NOTIFY_DONE;
318 if (msg != NETDEV_UNREGISTER && msg != NETDEV_DOWN)
319 return NOTIFY_DONE;
320 if (unlikely(raw_busy_notifier)) /* Check for reentrant bug. */
321 return NOTIFY_DONE;
322
323 spin_lock(&raw_notifier_lock);
324 list_for_each_entry(raw_busy_notifier, &raw_notifier_list, notifier) {
325 spin_unlock(&raw_notifier_lock);
326 raw_notify(raw_busy_notifier, msg, dev);
327 spin_lock(&raw_notifier_lock);
328 }
329 raw_busy_notifier = NULL;
330 spin_unlock(&raw_notifier_lock);
331 return NOTIFY_DONE;
332}
333
334static int raw_init(struct sock *sk)
335{
336 struct raw_sock *ro = raw_sk(sk);
337
338 ro->bound = 0;
339 ro->ifindex = 0;
340
341 /* set default filter to single entry dfilter */
342 ro->dfilter.can_id = 0;
343 ro->dfilter.can_mask = MASK_ALL;
344 ro->filter = &ro->dfilter;
345 ro->count = 1;
346
347 /* set default loopback behaviour */
348 ro->loopback = 1;
349 ro->recv_own_msgs = 0;
350 ro->fd_frames = 0;
351 ro->xl_frames = 0;
352 ro->join_filters = 0;
353
354 /* alloc_percpu provides zero'ed memory */
355 ro->uniq = alloc_percpu(struct uniqframe);
356 if (unlikely(!ro->uniq))
357 return -ENOMEM;
358
359 /* set notifier */
360 spin_lock(&raw_notifier_lock);
361 list_add_tail(&ro->notifier, &raw_notifier_list);
362 spin_unlock(&raw_notifier_lock);
363
364 return 0;
365}
366
367static int raw_release(struct socket *sock)
368{
369 struct sock *sk = sock->sk;
370 struct raw_sock *ro;
371
372 if (!sk)
373 return 0;
374
375 ro = raw_sk(sk);
376
377 spin_lock(&raw_notifier_lock);
378 while (raw_busy_notifier == ro) {
379 spin_unlock(&raw_notifier_lock);
380 schedule_timeout_uninterruptible(1);
381 spin_lock(&raw_notifier_lock);
382 }
383 list_del(&ro->notifier);
384 spin_unlock(&raw_notifier_lock);
385
386 lock_sock(sk);
387
388 /* remove current filters & unregister */
389 if (ro->bound) {
390 if (ro->ifindex) {
391 struct net_device *dev;
392
393 dev = dev_get_by_index(sock_net(sk), ro->ifindex);
394 if (dev) {
395 raw_disable_allfilters(dev_net(dev), dev, sk);
396 dev_put(dev);
397 }
398 } else {
399 raw_disable_allfilters(sock_net(sk), NULL, sk);
400 }
401 }
402
403 if (ro->count > 1)
404 kfree(ro->filter);
405
406 ro->ifindex = 0;
407 ro->bound = 0;
408 ro->count = 0;
409 free_percpu(ro->uniq);
410
411 sock_orphan(sk);
412 sock->sk = NULL;
413
414 release_sock(sk);
415 sock_put(sk);
416
417 return 0;
418}
419
420static int raw_bind(struct socket *sock, struct sockaddr *uaddr, int len)
421{
422 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
423 struct sock *sk = sock->sk;
424 struct raw_sock *ro = raw_sk(sk);
425 int ifindex;
426 int err = 0;
427 int notify_enetdown = 0;
428
429 if (len < RAW_MIN_NAMELEN)
430 return -EINVAL;
431 if (addr->can_family != AF_CAN)
432 return -EINVAL;
433
434 lock_sock(sk);
435
436 if (ro->bound && addr->can_ifindex == ro->ifindex)
437 goto out;
438
439 if (addr->can_ifindex) {
440 struct net_device *dev;
441
442 dev = dev_get_by_index(sock_net(sk), addr->can_ifindex);
443 if (!dev) {
444 err = -ENODEV;
445 goto out;
446 }
447 if (dev->type != ARPHRD_CAN) {
448 dev_put(dev);
449 err = -ENODEV;
450 goto out;
451 }
452 if (!(dev->flags & IFF_UP))
453 notify_enetdown = 1;
454
455 ifindex = dev->ifindex;
456
457 /* filters set by default/setsockopt */
458 err = raw_enable_allfilters(sock_net(sk), dev, sk);
459 dev_put(dev);
460 } else {
461 ifindex = 0;
462
463 /* filters set by default/setsockopt */
464 err = raw_enable_allfilters(sock_net(sk), NULL, sk);
465 }
466
467 if (!err) {
468 if (ro->bound) {
469 /* unregister old filters */
470 if (ro->ifindex) {
471 struct net_device *dev;
472
473 dev = dev_get_by_index(sock_net(sk),
474 ro->ifindex);
475 if (dev) {
476 raw_disable_allfilters(dev_net(dev),
477 dev, sk);
478 dev_put(dev);
479 }
480 } else {
481 raw_disable_allfilters(sock_net(sk), NULL, sk);
482 }
483 }
484 ro->ifindex = ifindex;
485 ro->bound = 1;
486 }
487
488 out:
489 release_sock(sk);
490
491 if (notify_enetdown) {
492 sk->sk_err = ENETDOWN;
493 if (!sock_flag(sk, SOCK_DEAD))
494 sk_error_report(sk);
495 }
496
497 return err;
498}
499
500static int raw_getname(struct socket *sock, struct sockaddr *uaddr,
501 int peer)
502{
503 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
504 struct sock *sk = sock->sk;
505 struct raw_sock *ro = raw_sk(sk);
506
507 if (peer)
508 return -EOPNOTSUPP;
509
510 memset(addr, 0, RAW_MIN_NAMELEN);
511 addr->can_family = AF_CAN;
512 addr->can_ifindex = ro->ifindex;
513
514 return RAW_MIN_NAMELEN;
515}
516
517static int raw_setsockopt(struct socket *sock, int level, int optname,
518 sockptr_t optval, unsigned int optlen)
519{
520 struct sock *sk = sock->sk;
521 struct raw_sock *ro = raw_sk(sk);
522 struct can_filter *filter = NULL; /* dyn. alloc'ed filters */
523 struct can_filter sfilter; /* single filter */
524 struct net_device *dev = NULL;
525 can_err_mask_t err_mask = 0;
526 int count = 0;
527 int err = 0;
528
529 if (level != SOL_CAN_RAW)
530 return -EINVAL;
531
532 switch (optname) {
533 case CAN_RAW_FILTER:
534 if (optlen % sizeof(struct can_filter) != 0)
535 return -EINVAL;
536
537 if (optlen > CAN_RAW_FILTER_MAX * sizeof(struct can_filter))
538 return -EINVAL;
539
540 count = optlen / sizeof(struct can_filter);
541
542 if (count > 1) {
543 /* filter does not fit into dfilter => alloc space */
544 filter = memdup_sockptr(optval, optlen);
545 if (IS_ERR(filter))
546 return PTR_ERR(filter);
547 } else if (count == 1) {
548 if (copy_from_sockptr(&sfilter, optval, sizeof(sfilter)))
549 return -EFAULT;
550 }
551
552 rtnl_lock();
553 lock_sock(sk);
554
555 if (ro->bound && ro->ifindex) {
556 dev = dev_get_by_index(sock_net(sk), ro->ifindex);
557 if (!dev) {
558 if (count > 1)
559 kfree(filter);
560 err = -ENODEV;
561 goto out_fil;
562 }
563 }
564
565 if (ro->bound) {
566 /* (try to) register the new filters */
567 if (count == 1)
568 err = raw_enable_filters(sock_net(sk), dev, sk,
569 &sfilter, 1);
570 else
571 err = raw_enable_filters(sock_net(sk), dev, sk,
572 filter, count);
573 if (err) {
574 if (count > 1)
575 kfree(filter);
576 goto out_fil;
577 }
578
579 /* remove old filter registrations */
580 raw_disable_filters(sock_net(sk), dev, sk, ro->filter,
581 ro->count);
582 }
583
584 /* remove old filter space */
585 if (ro->count > 1)
586 kfree(ro->filter);
587
588 /* link new filters to the socket */
589 if (count == 1) {
590 /* copy filter data for single filter */
591 ro->dfilter = sfilter;
592 filter = &ro->dfilter;
593 }
594 ro->filter = filter;
595 ro->count = count;
596
597 out_fil:
598 dev_put(dev);
599 release_sock(sk);
600 rtnl_unlock();
601
602 break;
603
604 case CAN_RAW_ERR_FILTER:
605 if (optlen != sizeof(err_mask))
606 return -EINVAL;
607
608 if (copy_from_sockptr(&err_mask, optval, optlen))
609 return -EFAULT;
610
611 err_mask &= CAN_ERR_MASK;
612
613 rtnl_lock();
614 lock_sock(sk);
615
616 if (ro->bound && ro->ifindex) {
617 dev = dev_get_by_index(sock_net(sk), ro->ifindex);
618 if (!dev) {
619 err = -ENODEV;
620 goto out_err;
621 }
622 }
623
624 /* remove current error mask */
625 if (ro->bound) {
626 /* (try to) register the new err_mask */
627 err = raw_enable_errfilter(sock_net(sk), dev, sk,
628 err_mask);
629
630 if (err)
631 goto out_err;
632
633 /* remove old err_mask registration */
634 raw_disable_errfilter(sock_net(sk), dev, sk,
635 ro->err_mask);
636 }
637
638 /* link new err_mask to the socket */
639 ro->err_mask = err_mask;
640
641 out_err:
642 dev_put(dev);
643 release_sock(sk);
644 rtnl_unlock();
645
646 break;
647
648 case CAN_RAW_LOOPBACK:
649 if (optlen != sizeof(ro->loopback))
650 return -EINVAL;
651
652 if (copy_from_sockptr(&ro->loopback, optval, optlen))
653 return -EFAULT;
654
655 break;
656
657 case CAN_RAW_RECV_OWN_MSGS:
658 if (optlen != sizeof(ro->recv_own_msgs))
659 return -EINVAL;
660
661 if (copy_from_sockptr(&ro->recv_own_msgs, optval, optlen))
662 return -EFAULT;
663
664 break;
665
666 case CAN_RAW_FD_FRAMES:
667 if (optlen != sizeof(ro->fd_frames))
668 return -EINVAL;
669
670 if (copy_from_sockptr(&ro->fd_frames, optval, optlen))
671 return -EFAULT;
672
673 /* Enabling CAN XL includes CAN FD */
674 if (ro->xl_frames && !ro->fd_frames) {
675 ro->fd_frames = ro->xl_frames;
676 return -EINVAL;
677 }
678 break;
679
680 case CAN_RAW_XL_FRAMES:
681 if (optlen != sizeof(ro->xl_frames))
682 return -EINVAL;
683
684 if (copy_from_sockptr(&ro->xl_frames, optval, optlen))
685 return -EFAULT;
686
687 /* Enabling CAN XL includes CAN FD */
688 if (ro->xl_frames)
689 ro->fd_frames = ro->xl_frames;
690 break;
691
692 case CAN_RAW_JOIN_FILTERS:
693 if (optlen != sizeof(ro->join_filters))
694 return -EINVAL;
695
696 if (copy_from_sockptr(&ro->join_filters, optval, optlen))
697 return -EFAULT;
698
699 break;
700
701 default:
702 return -ENOPROTOOPT;
703 }
704 return err;
705}
706
707static int raw_getsockopt(struct socket *sock, int level, int optname,
708 char __user *optval, int __user *optlen)
709{
710 struct sock *sk = sock->sk;
711 struct raw_sock *ro = raw_sk(sk);
712 int len;
713 void *val;
714 int err = 0;
715
716 if (level != SOL_CAN_RAW)
717 return -EINVAL;
718 if (get_user(len, optlen))
719 return -EFAULT;
720 if (len < 0)
721 return -EINVAL;
722
723 switch (optname) {
724 case CAN_RAW_FILTER:
725 lock_sock(sk);
726 if (ro->count > 0) {
727 int fsize = ro->count * sizeof(struct can_filter);
728
729 /* user space buffer to small for filter list? */
730 if (len < fsize) {
731 /* return -ERANGE and needed space in optlen */
732 err = -ERANGE;
733 if (put_user(fsize, optlen))
734 err = -EFAULT;
735 } else {
736 if (len > fsize)
737 len = fsize;
738 if (copy_to_user(optval, ro->filter, len))
739 err = -EFAULT;
740 }
741 } else {
742 len = 0;
743 }
744 release_sock(sk);
745
746 if (!err)
747 err = put_user(len, optlen);
748 return err;
749
750 case CAN_RAW_ERR_FILTER:
751 if (len > sizeof(can_err_mask_t))
752 len = sizeof(can_err_mask_t);
753 val = &ro->err_mask;
754 break;
755
756 case CAN_RAW_LOOPBACK:
757 if (len > sizeof(int))
758 len = sizeof(int);
759 val = &ro->loopback;
760 break;
761
762 case CAN_RAW_RECV_OWN_MSGS:
763 if (len > sizeof(int))
764 len = sizeof(int);
765 val = &ro->recv_own_msgs;
766 break;
767
768 case CAN_RAW_FD_FRAMES:
769 if (len > sizeof(int))
770 len = sizeof(int);
771 val = &ro->fd_frames;
772 break;
773
774 case CAN_RAW_XL_FRAMES:
775 if (len > sizeof(int))
776 len = sizeof(int);
777 val = &ro->xl_frames;
778 break;
779
780 case CAN_RAW_JOIN_FILTERS:
781 if (len > sizeof(int))
782 len = sizeof(int);
783 val = &ro->join_filters;
784 break;
785
786 default:
787 return -ENOPROTOOPT;
788 }
789
790 if (put_user(len, optlen))
791 return -EFAULT;
792 if (copy_to_user(optval, val, len))
793 return -EFAULT;
794 return 0;
795}
796
797static bool raw_bad_txframe(struct raw_sock *ro, struct sk_buff *skb, int mtu)
798{
799 /* Classical CAN -> no checks for flags and device capabilities */
800 if (can_is_can_skb(skb))
801 return false;
802
803 /* CAN FD -> needs to be enabled and a CAN FD or CAN XL device */
804 if (ro->fd_frames && can_is_canfd_skb(skb) &&
805 (mtu == CANFD_MTU || can_is_canxl_dev_mtu(mtu)))
806 return false;
807
808 /* CAN XL -> needs to be enabled and a CAN XL device */
809 if (ro->xl_frames && can_is_canxl_skb(skb) &&
810 can_is_canxl_dev_mtu(mtu))
811 return false;
812
813 return true;
814}
815
816static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
817{
818 struct sock *sk = sock->sk;
819 struct raw_sock *ro = raw_sk(sk);
820 struct sockcm_cookie sockc;
821 struct sk_buff *skb;
822 struct net_device *dev;
823 int ifindex;
824 int err = -EINVAL;
825
826 /* check for valid CAN frame sizes */
827 if (size < CANXL_HDR_SIZE + CANXL_MIN_DLEN || size > CANXL_MTU)
828 return -EINVAL;
829
830 if (msg->msg_name) {
831 DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name);
832
833 if (msg->msg_namelen < RAW_MIN_NAMELEN)
834 return -EINVAL;
835
836 if (addr->can_family != AF_CAN)
837 return -EINVAL;
838
839 ifindex = addr->can_ifindex;
840 } else {
841 ifindex = ro->ifindex;
842 }
843
844 dev = dev_get_by_index(sock_net(sk), ifindex);
845 if (!dev)
846 return -ENXIO;
847
848 skb = sock_alloc_send_skb(sk, size + sizeof(struct can_skb_priv),
849 msg->msg_flags & MSG_DONTWAIT, &err);
850 if (!skb)
851 goto put_dev;
852
853 can_skb_reserve(skb);
854 can_skb_prv(skb)->ifindex = dev->ifindex;
855 can_skb_prv(skb)->skbcnt = 0;
856
857 /* fill the skb before testing for valid CAN frames */
858 err = memcpy_from_msg(skb_put(skb, size), msg, size);
859 if (err < 0)
860 goto free_skb;
861
862 err = -EINVAL;
863 if (raw_bad_txframe(ro, skb, dev->mtu))
864 goto free_skb;
865
866 sockcm_init(&sockc, sk);
867 if (msg->msg_controllen) {
868 err = sock_cmsg_send(sk, msg, &sockc);
869 if (unlikely(err))
870 goto free_skb;
871 }
872
873 skb->dev = dev;
874 skb->priority = sk->sk_priority;
875 skb->mark = sk->sk_mark;
876 skb->tstamp = sockc.transmit_time;
877
878 skb_setup_tx_timestamp(skb, sockc.tsflags);
879
880 err = can_send(skb, ro->loopback);
881
882 dev_put(dev);
883
884 if (err)
885 goto send_failed;
886
887 return size;
888
889free_skb:
890 kfree_skb(skb);
891put_dev:
892 dev_put(dev);
893send_failed:
894 return err;
895}
896
897static int raw_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
898 int flags)
899{
900 struct sock *sk = sock->sk;
901 struct sk_buff *skb;
902 int err = 0;
903
904 if (flags & MSG_ERRQUEUE)
905 return sock_recv_errqueue(sk, msg, size,
906 SOL_CAN_RAW, SCM_CAN_RAW_ERRQUEUE);
907
908 skb = skb_recv_datagram(sk, flags, &err);
909 if (!skb)
910 return err;
911
912 if (size < skb->len)
913 msg->msg_flags |= MSG_TRUNC;
914 else
915 size = skb->len;
916
917 err = memcpy_to_msg(msg, skb->data, size);
918 if (err < 0) {
919 skb_free_datagram(sk, skb);
920 return err;
921 }
922
923 sock_recv_cmsgs(msg, sk, skb);
924
925 if (msg->msg_name) {
926 __sockaddr_check_size(RAW_MIN_NAMELEN);
927 msg->msg_namelen = RAW_MIN_NAMELEN;
928 memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
929 }
930
931 /* assign the flags that have been recorded in raw_rcv() */
932 msg->msg_flags |= *(raw_flags(skb));
933
934 skb_free_datagram(sk, skb);
935
936 return size;
937}
938
939static int raw_sock_no_ioctlcmd(struct socket *sock, unsigned int cmd,
940 unsigned long arg)
941{
942 /* no ioctls for socket layer -> hand it down to NIC layer */
943 return -ENOIOCTLCMD;
944}
945
946static const struct proto_ops raw_ops = {
947 .family = PF_CAN,
948 .release = raw_release,
949 .bind = raw_bind,
950 .connect = sock_no_connect,
951 .socketpair = sock_no_socketpair,
952 .accept = sock_no_accept,
953 .getname = raw_getname,
954 .poll = datagram_poll,
955 .ioctl = raw_sock_no_ioctlcmd,
956 .gettstamp = sock_gettstamp,
957 .listen = sock_no_listen,
958 .shutdown = sock_no_shutdown,
959 .setsockopt = raw_setsockopt,
960 .getsockopt = raw_getsockopt,
961 .sendmsg = raw_sendmsg,
962 .recvmsg = raw_recvmsg,
963 .mmap = sock_no_mmap,
964 .sendpage = sock_no_sendpage,
965};
966
967static struct proto raw_proto __read_mostly = {
968 .name = "CAN_RAW",
969 .owner = THIS_MODULE,
970 .obj_size = sizeof(struct raw_sock),
971 .init = raw_init,
972};
973
974static const struct can_proto raw_can_proto = {
975 .type = SOCK_RAW,
976 .protocol = CAN_RAW,
977 .ops = &raw_ops,
978 .prot = &raw_proto,
979};
980
981static struct notifier_block canraw_notifier = {
982 .notifier_call = raw_notifier
983};
984
985static __init int raw_module_init(void)
986{
987 int err;
988
989 pr_info("can: raw protocol\n");
990
991 err = register_netdevice_notifier(&canraw_notifier);
992 if (err)
993 return err;
994
995 err = can_proto_register(&raw_can_proto);
996 if (err < 0) {
997 pr_err("can: registration of raw protocol failed\n");
998 goto register_proto_failed;
999 }
1000
1001 return 0;
1002
1003register_proto_failed:
1004 unregister_netdevice_notifier(&canraw_notifier);
1005 return err;
1006}
1007
1008static __exit void raw_module_exit(void)
1009{
1010 can_proto_unregister(&raw_can_proto);
1011 unregister_netdevice_notifier(&canraw_notifier);
1012}
1013
1014module_init(raw_module_init);
1015module_exit(raw_module_exit);