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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 *net, struct net_device *dev,
185 struct sock *sk, struct can_filter *filter,
186 int count)
187{
188 int err = 0;
189 int i;
190
191 for (i = 0; i < count; i++) {
192 err = can_rx_register(net, dev, filter[i].can_id,
193 filter[i].can_mask,
194 raw_rcv, sk, "raw", sk);
195 if (err) {
196 /* clean up successfully registered filters */
197 while (--i >= 0)
198 can_rx_unregister(net, dev, filter[i].can_id,
199 filter[i].can_mask,
200 raw_rcv, sk);
201 break;
202 }
203 }
204
205 return err;
206}
207
208static int raw_enable_errfilter(struct net *net, struct net_device *dev,
209 struct sock *sk, can_err_mask_t err_mask)
210{
211 int err = 0;
212
213 if (err_mask)
214 err = can_rx_register(net, dev, 0, err_mask | CAN_ERR_FLAG,
215 raw_rcv, sk, "raw", sk);
216
217 return err;
218}
219
220static void raw_disable_filters(struct net *net, struct net_device *dev,
221 struct sock *sk, struct can_filter *filter,
222 int count)
223{
224 int i;
225
226 for (i = 0; i < count; i++)
227 can_rx_unregister(net, dev, filter[i].can_id,
228 filter[i].can_mask, raw_rcv, sk);
229}
230
231static inline void raw_disable_errfilter(struct net *net,
232 struct net_device *dev,
233 struct sock *sk,
234 can_err_mask_t err_mask)
235
236{
237 if (err_mask)
238 can_rx_unregister(net, dev, 0, err_mask | CAN_ERR_FLAG,
239 raw_rcv, sk);
240}
241
242static inline void raw_disable_allfilters(struct net *net,
243 struct net_device *dev,
244 struct sock *sk)
245{
246 struct raw_sock *ro = raw_sk(sk);
247
248 raw_disable_filters(net, dev, sk, ro->filter, ro->count);
249 raw_disable_errfilter(net, dev, sk, ro->err_mask);
250}
251
252static int raw_enable_allfilters(struct net *net, struct net_device *dev,
253 struct sock *sk)
254{
255 struct raw_sock *ro = raw_sk(sk);
256 int err;
257
258 err = raw_enable_filters(net, dev, sk, ro->filter, ro->count);
259 if (!err) {
260 err = raw_enable_errfilter(net, dev, sk, ro->err_mask);
261 if (err)
262 raw_disable_filters(net, dev, sk, ro->filter,
263 ro->count);
264 }
265
266 return err;
267}
268
269static int raw_notifier(struct notifier_block *nb,
270 unsigned long msg, void *ptr)
271{
272 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
273 struct raw_sock *ro = container_of(nb, struct raw_sock, notifier);
274 struct sock *sk = &ro->sk;
275
276 if (!net_eq(dev_net(dev), sock_net(sk)))
277 return NOTIFY_DONE;
278
279 if (dev->type != ARPHRD_CAN)
280 return NOTIFY_DONE;
281
282 if (ro->ifindex != dev->ifindex)
283 return NOTIFY_DONE;
284
285 switch (msg) {
286
287 case NETDEV_UNREGISTER:
288 lock_sock(sk);
289 /* remove current filters & unregister */
290 if (ro->bound)
291 raw_disable_allfilters(dev_net(dev), dev, sk);
292
293 if (ro->count > 1)
294 kfree(ro->filter);
295
296 ro->ifindex = 0;
297 ro->bound = 0;
298 ro->count = 0;
299 release_sock(sk);
300
301 sk->sk_err = ENODEV;
302 if (!sock_flag(sk, SOCK_DEAD))
303 sk->sk_error_report(sk);
304 break;
305
306 case NETDEV_DOWN:
307 sk->sk_err = ENETDOWN;
308 if (!sock_flag(sk, SOCK_DEAD))
309 sk->sk_error_report(sk);
310 break;
311 }
312
313 return NOTIFY_DONE;
314}
315
316static int raw_init(struct sock *sk)
317{
318 struct raw_sock *ro = raw_sk(sk);
319
320 ro->bound = 0;
321 ro->ifindex = 0;
322
323 /* set default filter to single entry dfilter */
324 ro->dfilter.can_id = 0;
325 ro->dfilter.can_mask = MASK_ALL;
326 ro->filter = &ro->dfilter;
327 ro->count = 1;
328
329 /* set default loopback behaviour */
330 ro->loopback = 1;
331 ro->recv_own_msgs = 0;
332 ro->fd_frames = 0;
333 ro->join_filters = 0;
334
335 /* alloc_percpu provides zero'ed memory */
336 ro->uniq = alloc_percpu(struct uniqframe);
337 if (unlikely(!ro->uniq))
338 return -ENOMEM;
339
340 /* set notifier */
341 ro->notifier.notifier_call = raw_notifier;
342
343 register_netdevice_notifier(&ro->notifier);
344
345 return 0;
346}
347
348static int raw_release(struct socket *sock)
349{
350 struct sock *sk = sock->sk;
351 struct raw_sock *ro;
352
353 if (!sk)
354 return 0;
355
356 ro = raw_sk(sk);
357
358 unregister_netdevice_notifier(&ro->notifier);
359
360 lock_sock(sk);
361
362 /* remove current filters & unregister */
363 if (ro->bound) {
364 if (ro->ifindex) {
365 struct net_device *dev;
366
367 dev = dev_get_by_index(sock_net(sk), ro->ifindex);
368 if (dev) {
369 raw_disable_allfilters(dev_net(dev), dev, sk);
370 dev_put(dev);
371 }
372 } else
373 raw_disable_allfilters(sock_net(sk), NULL, sk);
374 }
375
376 if (ro->count > 1)
377 kfree(ro->filter);
378
379 ro->ifindex = 0;
380 ro->bound = 0;
381 ro->count = 0;
382 free_percpu(ro->uniq);
383
384 sock_orphan(sk);
385 sock->sk = NULL;
386
387 release_sock(sk);
388 sock_put(sk);
389
390 return 0;
391}
392
393static int raw_bind(struct socket *sock, struct sockaddr *uaddr, int len)
394{
395 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
396 struct sock *sk = sock->sk;
397 struct raw_sock *ro = raw_sk(sk);
398 int ifindex;
399 int err = 0;
400 int notify_enetdown = 0;
401
402 if (len < sizeof(*addr))
403 return -EINVAL;
404 if (addr->can_family != AF_CAN)
405 return -EINVAL;
406
407 lock_sock(sk);
408
409 if (ro->bound && addr->can_ifindex == ro->ifindex)
410 goto out;
411
412 if (addr->can_ifindex) {
413 struct net_device *dev;
414
415 dev = dev_get_by_index(sock_net(sk), addr->can_ifindex);
416 if (!dev) {
417 err = -ENODEV;
418 goto out;
419 }
420 if (dev->type != ARPHRD_CAN) {
421 dev_put(dev);
422 err = -ENODEV;
423 goto out;
424 }
425 if (!(dev->flags & IFF_UP))
426 notify_enetdown = 1;
427
428 ifindex = dev->ifindex;
429
430 /* filters set by default/setsockopt */
431 err = raw_enable_allfilters(sock_net(sk), dev, sk);
432 dev_put(dev);
433 } else {
434 ifindex = 0;
435
436 /* filters set by default/setsockopt */
437 err = raw_enable_allfilters(sock_net(sk), NULL, sk);
438 }
439
440 if (!err) {
441 if (ro->bound) {
442 /* unregister old filters */
443 if (ro->ifindex) {
444 struct net_device *dev;
445
446 dev = dev_get_by_index(sock_net(sk),
447 ro->ifindex);
448 if (dev) {
449 raw_disable_allfilters(dev_net(dev),
450 dev, sk);
451 dev_put(dev);
452 }
453 } else
454 raw_disable_allfilters(sock_net(sk), NULL, sk);
455 }
456 ro->ifindex = ifindex;
457 ro->bound = 1;
458 }
459
460 out:
461 release_sock(sk);
462
463 if (notify_enetdown) {
464 sk->sk_err = ENETDOWN;
465 if (!sock_flag(sk, SOCK_DEAD))
466 sk->sk_error_report(sk);
467 }
468
469 return err;
470}
471
472static int raw_getname(struct socket *sock, struct sockaddr *uaddr,
473 int peer)
474{
475 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
476 struct sock *sk = sock->sk;
477 struct raw_sock *ro = raw_sk(sk);
478
479 if (peer)
480 return -EOPNOTSUPP;
481
482 memset(addr, 0, sizeof(*addr));
483 addr->can_family = AF_CAN;
484 addr->can_ifindex = ro->ifindex;
485
486 return sizeof(*addr);
487}
488
489static int raw_setsockopt(struct socket *sock, int level, int optname,
490 char __user *optval, unsigned int optlen)
491{
492 struct sock *sk = sock->sk;
493 struct raw_sock *ro = raw_sk(sk);
494 struct can_filter *filter = NULL; /* dyn. alloc'ed filters */
495 struct can_filter sfilter; /* single filter */
496 struct net_device *dev = NULL;
497 can_err_mask_t err_mask = 0;
498 int count = 0;
499 int err = 0;
500
501 if (level != SOL_CAN_RAW)
502 return -EINVAL;
503
504 switch (optname) {
505
506 case CAN_RAW_FILTER:
507 if (optlen % sizeof(struct can_filter) != 0)
508 return -EINVAL;
509
510 if (optlen > CAN_RAW_FILTER_MAX * sizeof(struct can_filter))
511 return -EINVAL;
512
513 count = optlen / sizeof(struct can_filter);
514
515 if (count > 1) {
516 /* filter does not fit into dfilter => alloc space */
517 filter = memdup_user(optval, optlen);
518 if (IS_ERR(filter))
519 return PTR_ERR(filter);
520 } else if (count == 1) {
521 if (copy_from_user(&sfilter, optval, sizeof(sfilter)))
522 return -EFAULT;
523 }
524
525 lock_sock(sk);
526
527 if (ro->bound && ro->ifindex)
528 dev = dev_get_by_index(sock_net(sk), ro->ifindex);
529
530 if (ro->bound) {
531 /* (try to) register the new filters */
532 if (count == 1)
533 err = raw_enable_filters(sock_net(sk), dev, sk,
534 &sfilter, 1);
535 else
536 err = raw_enable_filters(sock_net(sk), dev, sk,
537 filter, count);
538 if (err) {
539 if (count > 1)
540 kfree(filter);
541 goto out_fil;
542 }
543
544 /* remove old filter registrations */
545 raw_disable_filters(sock_net(sk), dev, sk, ro->filter,
546 ro->count);
547 }
548
549 /* remove old filter space */
550 if (ro->count > 1)
551 kfree(ro->filter);
552
553 /* link new filters to the socket */
554 if (count == 1) {
555 /* copy filter data for single filter */
556 ro->dfilter = sfilter;
557 filter = &ro->dfilter;
558 }
559 ro->filter = filter;
560 ro->count = count;
561
562 out_fil:
563 if (dev)
564 dev_put(dev);
565
566 release_sock(sk);
567
568 break;
569
570 case CAN_RAW_ERR_FILTER:
571 if (optlen != sizeof(err_mask))
572 return -EINVAL;
573
574 if (copy_from_user(&err_mask, optval, optlen))
575 return -EFAULT;
576
577 err_mask &= CAN_ERR_MASK;
578
579 lock_sock(sk);
580
581 if (ro->bound && ro->ifindex)
582 dev = dev_get_by_index(sock_net(sk), ro->ifindex);
583
584 /* remove current error mask */
585 if (ro->bound) {
586 /* (try to) register the new err_mask */
587 err = raw_enable_errfilter(sock_net(sk), dev, sk,
588 err_mask);
589
590 if (err)
591 goto out_err;
592
593 /* remove old err_mask registration */
594 raw_disable_errfilter(sock_net(sk), dev, sk,
595 ro->err_mask);
596 }
597
598 /* link new err_mask to the socket */
599 ro->err_mask = err_mask;
600
601 out_err:
602 if (dev)
603 dev_put(dev);
604
605 release_sock(sk);
606
607 break;
608
609 case CAN_RAW_LOOPBACK:
610 if (optlen != sizeof(ro->loopback))
611 return -EINVAL;
612
613 if (copy_from_user(&ro->loopback, optval, optlen))
614 return -EFAULT;
615
616 break;
617
618 case CAN_RAW_RECV_OWN_MSGS:
619 if (optlen != sizeof(ro->recv_own_msgs))
620 return -EINVAL;
621
622 if (copy_from_user(&ro->recv_own_msgs, optval, optlen))
623 return -EFAULT;
624
625 break;
626
627 case CAN_RAW_FD_FRAMES:
628 if (optlen != sizeof(ro->fd_frames))
629 return -EINVAL;
630
631 if (copy_from_user(&ro->fd_frames, optval, optlen))
632 return -EFAULT;
633
634 break;
635
636 case CAN_RAW_JOIN_FILTERS:
637 if (optlen != sizeof(ro->join_filters))
638 return -EINVAL;
639
640 if (copy_from_user(&ro->join_filters, optval, optlen))
641 return -EFAULT;
642
643 break;
644
645 default:
646 return -ENOPROTOOPT;
647 }
648 return err;
649}
650
651static int raw_getsockopt(struct socket *sock, int level, int optname,
652 char __user *optval, int __user *optlen)
653{
654 struct sock *sk = sock->sk;
655 struct raw_sock *ro = raw_sk(sk);
656 int len;
657 void *val;
658 int err = 0;
659
660 if (level != SOL_CAN_RAW)
661 return -EINVAL;
662 if (get_user(len, optlen))
663 return -EFAULT;
664 if (len < 0)
665 return -EINVAL;
666
667 switch (optname) {
668
669 case CAN_RAW_FILTER:
670 lock_sock(sk);
671 if (ro->count > 0) {
672 int fsize = ro->count * sizeof(struct can_filter);
673 if (len > fsize)
674 len = fsize;
675 if (copy_to_user(optval, ro->filter, len))
676 err = -EFAULT;
677 } else
678 len = 0;
679 release_sock(sk);
680
681 if (!err)
682 err = put_user(len, optlen);
683 return err;
684
685 case CAN_RAW_ERR_FILTER:
686 if (len > sizeof(can_err_mask_t))
687 len = sizeof(can_err_mask_t);
688 val = &ro->err_mask;
689 break;
690
691 case CAN_RAW_LOOPBACK:
692 if (len > sizeof(int))
693 len = sizeof(int);
694 val = &ro->loopback;
695 break;
696
697 case CAN_RAW_RECV_OWN_MSGS:
698 if (len > sizeof(int))
699 len = sizeof(int);
700 val = &ro->recv_own_msgs;
701 break;
702
703 case CAN_RAW_FD_FRAMES:
704 if (len > sizeof(int))
705 len = sizeof(int);
706 val = &ro->fd_frames;
707 break;
708
709 case CAN_RAW_JOIN_FILTERS:
710 if (len > sizeof(int))
711 len = sizeof(int);
712 val = &ro->join_filters;
713 break;
714
715 default:
716 return -ENOPROTOOPT;
717 }
718
719 if (put_user(len, optlen))
720 return -EFAULT;
721 if (copy_to_user(optval, val, len))
722 return -EFAULT;
723 return 0;
724}
725
726static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
727{
728 struct sock *sk = sock->sk;
729 struct raw_sock *ro = raw_sk(sk);
730 struct sk_buff *skb;
731 struct net_device *dev;
732 int ifindex;
733 int err;
734
735 if (msg->msg_name) {
736 DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name);
737
738 if (msg->msg_namelen < sizeof(*addr))
739 return -EINVAL;
740
741 if (addr->can_family != AF_CAN)
742 return -EINVAL;
743
744 ifindex = addr->can_ifindex;
745 } else
746 ifindex = ro->ifindex;
747
748 if (ro->fd_frames) {
749 if (unlikely(size != CANFD_MTU && size != CAN_MTU))
750 return -EINVAL;
751 } else {
752 if (unlikely(size != CAN_MTU))
753 return -EINVAL;
754 }
755
756 dev = dev_get_by_index(sock_net(sk), ifindex);
757 if (!dev)
758 return -ENXIO;
759
760 skb = sock_alloc_send_skb(sk, size + sizeof(struct can_skb_priv),
761 msg->msg_flags & MSG_DONTWAIT, &err);
762 if (!skb)
763 goto put_dev;
764
765 can_skb_reserve(skb);
766 can_skb_prv(skb)->ifindex = dev->ifindex;
767 can_skb_prv(skb)->skbcnt = 0;
768
769 err = memcpy_from_msg(skb_put(skb, size), msg, size);
770 if (err < 0)
771 goto free_skb;
772
773 sock_tx_timestamp(sk, sk->sk_tsflags, &skb_shinfo(skb)->tx_flags);
774
775 skb->dev = dev;
776 skb->sk = sk;
777 skb->priority = sk->sk_priority;
778
779 err = can_send(skb, ro->loopback);
780
781 dev_put(dev);
782
783 if (err)
784 goto send_failed;
785
786 return size;
787
788free_skb:
789 kfree_skb(skb);
790put_dev:
791 dev_put(dev);
792send_failed:
793 return err;
794}
795
796static int raw_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
797 int flags)
798{
799 struct sock *sk = sock->sk;
800 struct sk_buff *skb;
801 int err = 0;
802 int noblock;
803
804 noblock = flags & MSG_DONTWAIT;
805 flags &= ~MSG_DONTWAIT;
806
807 skb = skb_recv_datagram(sk, flags, noblock, &err);
808 if (!skb)
809 return err;
810
811 if (size < skb->len)
812 msg->msg_flags |= MSG_TRUNC;
813 else
814 size = skb->len;
815
816 err = memcpy_to_msg(msg, skb->data, size);
817 if (err < 0) {
818 skb_free_datagram(sk, skb);
819 return err;
820 }
821
822 sock_recv_ts_and_drops(msg, sk, skb);
823
824 if (msg->msg_name) {
825 __sockaddr_check_size(sizeof(struct sockaddr_can));
826 msg->msg_namelen = sizeof(struct sockaddr_can);
827 memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
828 }
829
830 /* assign the flags that have been recorded in raw_rcv() */
831 msg->msg_flags |= *(raw_flags(skb));
832
833 skb_free_datagram(sk, skb);
834
835 return size;
836}
837
838static const struct proto_ops raw_ops = {
839 .family = PF_CAN,
840 .release = raw_release,
841 .bind = raw_bind,
842 .connect = sock_no_connect,
843 .socketpair = sock_no_socketpair,
844 .accept = sock_no_accept,
845 .getname = raw_getname,
846 .poll = datagram_poll,
847 .ioctl = can_ioctl, /* use can_ioctl() from af_can.c */
848 .listen = sock_no_listen,
849 .shutdown = sock_no_shutdown,
850 .setsockopt = raw_setsockopt,
851 .getsockopt = raw_getsockopt,
852 .sendmsg = raw_sendmsg,
853 .recvmsg = raw_recvmsg,
854 .mmap = sock_no_mmap,
855 .sendpage = sock_no_sendpage,
856};
857
858static struct proto raw_proto __read_mostly = {
859 .name = "CAN_RAW",
860 .owner = THIS_MODULE,
861 .obj_size = sizeof(struct raw_sock),
862 .init = raw_init,
863};
864
865static const struct can_proto raw_can_proto = {
866 .type = SOCK_RAW,
867 .protocol = CAN_RAW,
868 .ops = &raw_ops,
869 .prot = &raw_proto,
870};
871
872static __init int raw_module_init(void)
873{
874 int err;
875
876 pr_info("can: raw protocol (rev " CAN_RAW_VERSION ")\n");
877
878 err = can_proto_register(&raw_can_proto);
879 if (err < 0)
880 printk(KERN_ERR "can: registration of raw protocol failed\n");
881
882 return err;
883}
884
885static __exit void raw_module_exit(void)
886{
887 can_proto_unregister(&raw_can_proto);
888}
889
890module_init(raw_module_init);
891module_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 net_device *dev;
88 netdevice_tracker dev_tracker;
89 struct list_head notifier;
90 int loopback;
91 int recv_own_msgs;
92 int fd_frames;
93 int xl_frames;
94 int join_filters;
95 int count; /* number of active filters */
96 struct can_filter dfilter; /* default/single filter */
97 struct can_filter *filter; /* pointer to filter(s) */
98 can_err_mask_t err_mask;
99 struct uniqframe __percpu *uniq;
100};
101
102static LIST_HEAD(raw_notifier_list);
103static DEFINE_SPINLOCK(raw_notifier_lock);
104static struct raw_sock *raw_busy_notifier;
105
106/* Return pointer to store the extra msg flags for raw_recvmsg().
107 * We use the space of one unsigned int beyond the 'struct sockaddr_can'
108 * in skb->cb.
109 */
110static inline unsigned int *raw_flags(struct sk_buff *skb)
111{
112 sock_skb_cb_check_size(sizeof(struct sockaddr_can) +
113 sizeof(unsigned int));
114
115 /* return pointer after struct sockaddr_can */
116 return (unsigned int *)(&((struct sockaddr_can *)skb->cb)[1]);
117}
118
119static inline struct raw_sock *raw_sk(const struct sock *sk)
120{
121 return (struct raw_sock *)sk;
122}
123
124static void raw_rcv(struct sk_buff *oskb, void *data)
125{
126 struct sock *sk = (struct sock *)data;
127 struct raw_sock *ro = raw_sk(sk);
128 struct sockaddr_can *addr;
129 struct sk_buff *skb;
130 unsigned int *pflags;
131
132 /* check the received tx sock reference */
133 if (!ro->recv_own_msgs && oskb->sk == sk)
134 return;
135
136 /* make sure to not pass oversized frames to the socket */
137 if ((!ro->fd_frames && can_is_canfd_skb(oskb)) ||
138 (!ro->xl_frames && can_is_canxl_skb(oskb)))
139 return;
140
141 /* eliminate multiple filter matches for the same skb */
142 if (this_cpu_ptr(ro->uniq)->skb == oskb &&
143 this_cpu_ptr(ro->uniq)->skbcnt == can_skb_prv(oskb)->skbcnt) {
144 if (!ro->join_filters)
145 return;
146
147 this_cpu_inc(ro->uniq->join_rx_count);
148 /* drop frame until all enabled filters matched */
149 if (this_cpu_ptr(ro->uniq)->join_rx_count < ro->count)
150 return;
151 } else {
152 this_cpu_ptr(ro->uniq)->skb = oskb;
153 this_cpu_ptr(ro->uniq)->skbcnt = can_skb_prv(oskb)->skbcnt;
154 this_cpu_ptr(ro->uniq)->join_rx_count = 1;
155 /* drop first frame to check all enabled filters? */
156 if (ro->join_filters && ro->count > 1)
157 return;
158 }
159
160 /* clone the given skb to be able to enqueue it into the rcv queue */
161 skb = skb_clone(oskb, GFP_ATOMIC);
162 if (!skb)
163 return;
164
165 /* Put the datagram to the queue so that raw_recvmsg() can get
166 * it from there. We need to pass the interface index to
167 * raw_recvmsg(). We pass a whole struct sockaddr_can in
168 * skb->cb containing the interface index.
169 */
170
171 sock_skb_cb_check_size(sizeof(struct sockaddr_can));
172 addr = (struct sockaddr_can *)skb->cb;
173 memset(addr, 0, sizeof(*addr));
174 addr->can_family = AF_CAN;
175 addr->can_ifindex = skb->dev->ifindex;
176
177 /* add CAN specific message flags for raw_recvmsg() */
178 pflags = raw_flags(skb);
179 *pflags = 0;
180 if (oskb->sk)
181 *pflags |= MSG_DONTROUTE;
182 if (oskb->sk == sk)
183 *pflags |= MSG_CONFIRM;
184
185 if (sock_queue_rcv_skb(sk, skb) < 0)
186 kfree_skb(skb);
187}
188
189static int raw_enable_filters(struct net *net, struct net_device *dev,
190 struct sock *sk, struct can_filter *filter,
191 int count)
192{
193 int err = 0;
194 int i;
195
196 for (i = 0; i < count; i++) {
197 err = can_rx_register(net, dev, filter[i].can_id,
198 filter[i].can_mask,
199 raw_rcv, sk, "raw", sk);
200 if (err) {
201 /* clean up successfully registered filters */
202 while (--i >= 0)
203 can_rx_unregister(net, dev, filter[i].can_id,
204 filter[i].can_mask,
205 raw_rcv, sk);
206 break;
207 }
208 }
209
210 return err;
211}
212
213static int raw_enable_errfilter(struct net *net, struct net_device *dev,
214 struct sock *sk, can_err_mask_t err_mask)
215{
216 int err = 0;
217
218 if (err_mask)
219 err = can_rx_register(net, dev, 0, err_mask | CAN_ERR_FLAG,
220 raw_rcv, sk, "raw", sk);
221
222 return err;
223}
224
225static void raw_disable_filters(struct net *net, struct net_device *dev,
226 struct sock *sk, struct can_filter *filter,
227 int count)
228{
229 int i;
230
231 for (i = 0; i < count; i++)
232 can_rx_unregister(net, dev, filter[i].can_id,
233 filter[i].can_mask, raw_rcv, sk);
234}
235
236static inline void raw_disable_errfilter(struct net *net,
237 struct net_device *dev,
238 struct sock *sk,
239 can_err_mask_t err_mask)
240
241{
242 if (err_mask)
243 can_rx_unregister(net, dev, 0, err_mask | CAN_ERR_FLAG,
244 raw_rcv, sk);
245}
246
247static inline void raw_disable_allfilters(struct net *net,
248 struct net_device *dev,
249 struct sock *sk)
250{
251 struct raw_sock *ro = raw_sk(sk);
252
253 raw_disable_filters(net, dev, sk, ro->filter, ro->count);
254 raw_disable_errfilter(net, dev, sk, ro->err_mask);
255}
256
257static int raw_enable_allfilters(struct net *net, struct net_device *dev,
258 struct sock *sk)
259{
260 struct raw_sock *ro = raw_sk(sk);
261 int err;
262
263 err = raw_enable_filters(net, dev, sk, ro->filter, ro->count);
264 if (!err) {
265 err = raw_enable_errfilter(net, dev, sk, ro->err_mask);
266 if (err)
267 raw_disable_filters(net, dev, sk, ro->filter,
268 ro->count);
269 }
270
271 return err;
272}
273
274static void raw_notify(struct raw_sock *ro, unsigned long msg,
275 struct net_device *dev)
276{
277 struct sock *sk = &ro->sk;
278
279 if (!net_eq(dev_net(dev), sock_net(sk)))
280 return;
281
282 if (ro->dev != dev)
283 return;
284
285 switch (msg) {
286 case NETDEV_UNREGISTER:
287 lock_sock(sk);
288 /* remove current filters & unregister */
289 if (ro->bound) {
290 raw_disable_allfilters(dev_net(dev), dev, sk);
291 netdev_put(dev, &ro->dev_tracker);
292 }
293
294 if (ro->count > 1)
295 kfree(ro->filter);
296
297 ro->ifindex = 0;
298 ro->bound = 0;
299 ro->dev = NULL;
300 ro->count = 0;
301 release_sock(sk);
302
303 sk->sk_err = ENODEV;
304 if (!sock_flag(sk, SOCK_DEAD))
305 sk_error_report(sk);
306 break;
307
308 case NETDEV_DOWN:
309 sk->sk_err = ENETDOWN;
310 if (!sock_flag(sk, SOCK_DEAD))
311 sk_error_report(sk);
312 break;
313 }
314}
315
316static int raw_notifier(struct notifier_block *nb, unsigned long msg,
317 void *ptr)
318{
319 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
320
321 if (dev->type != ARPHRD_CAN)
322 return NOTIFY_DONE;
323 if (msg != NETDEV_UNREGISTER && msg != NETDEV_DOWN)
324 return NOTIFY_DONE;
325 if (unlikely(raw_busy_notifier)) /* Check for reentrant bug. */
326 return NOTIFY_DONE;
327
328 spin_lock(&raw_notifier_lock);
329 list_for_each_entry(raw_busy_notifier, &raw_notifier_list, notifier) {
330 spin_unlock(&raw_notifier_lock);
331 raw_notify(raw_busy_notifier, msg, dev);
332 spin_lock(&raw_notifier_lock);
333 }
334 raw_busy_notifier = NULL;
335 spin_unlock(&raw_notifier_lock);
336 return NOTIFY_DONE;
337}
338
339static int raw_init(struct sock *sk)
340{
341 struct raw_sock *ro = raw_sk(sk);
342
343 ro->bound = 0;
344 ro->ifindex = 0;
345 ro->dev = NULL;
346
347 /* set default filter to single entry dfilter */
348 ro->dfilter.can_id = 0;
349 ro->dfilter.can_mask = MASK_ALL;
350 ro->filter = &ro->dfilter;
351 ro->count = 1;
352
353 /* set default loopback behaviour */
354 ro->loopback = 1;
355 ro->recv_own_msgs = 0;
356 ro->fd_frames = 0;
357 ro->xl_frames = 0;
358 ro->join_filters = 0;
359
360 /* alloc_percpu provides zero'ed memory */
361 ro->uniq = alloc_percpu(struct uniqframe);
362 if (unlikely(!ro->uniq))
363 return -ENOMEM;
364
365 /* set notifier */
366 spin_lock(&raw_notifier_lock);
367 list_add_tail(&ro->notifier, &raw_notifier_list);
368 spin_unlock(&raw_notifier_lock);
369
370 return 0;
371}
372
373static int raw_release(struct socket *sock)
374{
375 struct sock *sk = sock->sk;
376 struct raw_sock *ro;
377
378 if (!sk)
379 return 0;
380
381 ro = raw_sk(sk);
382
383 spin_lock(&raw_notifier_lock);
384 while (raw_busy_notifier == ro) {
385 spin_unlock(&raw_notifier_lock);
386 schedule_timeout_uninterruptible(1);
387 spin_lock(&raw_notifier_lock);
388 }
389 list_del(&ro->notifier);
390 spin_unlock(&raw_notifier_lock);
391
392 rtnl_lock();
393 lock_sock(sk);
394
395 /* remove current filters & unregister */
396 if (ro->bound) {
397 if (ro->dev) {
398 raw_disable_allfilters(dev_net(ro->dev), ro->dev, sk);
399 netdev_put(ro->dev, &ro->dev_tracker);
400 } else {
401 raw_disable_allfilters(sock_net(sk), NULL, sk);
402 }
403 }
404
405 if (ro->count > 1)
406 kfree(ro->filter);
407
408 ro->ifindex = 0;
409 ro->bound = 0;
410 ro->dev = NULL;
411 ro->count = 0;
412 free_percpu(ro->uniq);
413
414 sock_orphan(sk);
415 sock->sk = NULL;
416
417 release_sock(sk);
418 rtnl_unlock();
419
420 sock_put(sk);
421
422 return 0;
423}
424
425static int raw_bind(struct socket *sock, struct sockaddr *uaddr, int len)
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 struct net_device *dev = NULL;
431 int ifindex;
432 int err = 0;
433 int notify_enetdown = 0;
434
435 if (len < RAW_MIN_NAMELEN)
436 return -EINVAL;
437 if (addr->can_family != AF_CAN)
438 return -EINVAL;
439
440 rtnl_lock();
441 lock_sock(sk);
442
443 if (ro->bound && addr->can_ifindex == ro->ifindex)
444 goto out;
445
446 if (addr->can_ifindex) {
447 dev = dev_get_by_index(sock_net(sk), addr->can_ifindex);
448 if (!dev) {
449 err = -ENODEV;
450 goto out;
451 }
452 if (dev->type != ARPHRD_CAN) {
453 err = -ENODEV;
454 goto out_put_dev;
455 }
456
457 if (!(dev->flags & IFF_UP))
458 notify_enetdown = 1;
459
460 ifindex = dev->ifindex;
461
462 /* filters set by default/setsockopt */
463 err = raw_enable_allfilters(sock_net(sk), dev, sk);
464 if (err)
465 goto out_put_dev;
466
467 } else {
468 ifindex = 0;
469
470 /* filters set by default/setsockopt */
471 err = raw_enable_allfilters(sock_net(sk), NULL, sk);
472 }
473
474 if (!err) {
475 if (ro->bound) {
476 /* unregister old filters */
477 if (ro->dev) {
478 raw_disable_allfilters(dev_net(ro->dev),
479 ro->dev, sk);
480 /* drop reference to old ro->dev */
481 netdev_put(ro->dev, &ro->dev_tracker);
482 } else {
483 raw_disable_allfilters(sock_net(sk), NULL, sk);
484 }
485 }
486 ro->ifindex = ifindex;
487 ro->bound = 1;
488 /* bind() ok -> hold a reference for new ro->dev */
489 ro->dev = dev;
490 if (ro->dev)
491 netdev_hold(ro->dev, &ro->dev_tracker, GFP_KERNEL);
492 }
493
494out_put_dev:
495 /* remove potential reference from dev_get_by_index() */
496 dev_put(dev);
497out:
498 release_sock(sk);
499 rtnl_unlock();
500
501 if (notify_enetdown) {
502 sk->sk_err = ENETDOWN;
503 if (!sock_flag(sk, SOCK_DEAD))
504 sk_error_report(sk);
505 }
506
507 return err;
508}
509
510static int raw_getname(struct socket *sock, struct sockaddr *uaddr,
511 int peer)
512{
513 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
514 struct sock *sk = sock->sk;
515 struct raw_sock *ro = raw_sk(sk);
516
517 if (peer)
518 return -EOPNOTSUPP;
519
520 memset(addr, 0, RAW_MIN_NAMELEN);
521 addr->can_family = AF_CAN;
522 addr->can_ifindex = ro->ifindex;
523
524 return RAW_MIN_NAMELEN;
525}
526
527static int raw_setsockopt(struct socket *sock, int level, int optname,
528 sockptr_t optval, unsigned int optlen)
529{
530 struct sock *sk = sock->sk;
531 struct raw_sock *ro = raw_sk(sk);
532 struct can_filter *filter = NULL; /* dyn. alloc'ed filters */
533 struct can_filter sfilter; /* single filter */
534 struct net_device *dev = NULL;
535 can_err_mask_t err_mask = 0;
536 int fd_frames;
537 int count = 0;
538 int err = 0;
539
540 if (level != SOL_CAN_RAW)
541 return -EINVAL;
542
543 switch (optname) {
544 case CAN_RAW_FILTER:
545 if (optlen % sizeof(struct can_filter) != 0)
546 return -EINVAL;
547
548 if (optlen > CAN_RAW_FILTER_MAX * sizeof(struct can_filter))
549 return -EINVAL;
550
551 count = optlen / sizeof(struct can_filter);
552
553 if (count > 1) {
554 /* filter does not fit into dfilter => alloc space */
555 filter = memdup_sockptr(optval, optlen);
556 if (IS_ERR(filter))
557 return PTR_ERR(filter);
558 } else if (count == 1) {
559 if (copy_from_sockptr(&sfilter, optval, sizeof(sfilter)))
560 return -EFAULT;
561 }
562
563 rtnl_lock();
564 lock_sock(sk);
565
566 dev = ro->dev;
567 if (ro->bound && dev) {
568 if (dev->reg_state != NETREG_REGISTERED) {
569 if (count > 1)
570 kfree(filter);
571 err = -ENODEV;
572 goto out_fil;
573 }
574 }
575
576 if (ro->bound) {
577 /* (try to) register the new filters */
578 if (count == 1)
579 err = raw_enable_filters(sock_net(sk), dev, sk,
580 &sfilter, 1);
581 else
582 err = raw_enable_filters(sock_net(sk), dev, sk,
583 filter, count);
584 if (err) {
585 if (count > 1)
586 kfree(filter);
587 goto out_fil;
588 }
589
590 /* remove old filter registrations */
591 raw_disable_filters(sock_net(sk), dev, sk, ro->filter,
592 ro->count);
593 }
594
595 /* remove old filter space */
596 if (ro->count > 1)
597 kfree(ro->filter);
598
599 /* link new filters to the socket */
600 if (count == 1) {
601 /* copy filter data for single filter */
602 ro->dfilter = sfilter;
603 filter = &ro->dfilter;
604 }
605 ro->filter = filter;
606 ro->count = count;
607
608 out_fil:
609 release_sock(sk);
610 rtnl_unlock();
611
612 break;
613
614 case CAN_RAW_ERR_FILTER:
615 if (optlen != sizeof(err_mask))
616 return -EINVAL;
617
618 if (copy_from_sockptr(&err_mask, optval, optlen))
619 return -EFAULT;
620
621 err_mask &= CAN_ERR_MASK;
622
623 rtnl_lock();
624 lock_sock(sk);
625
626 dev = ro->dev;
627 if (ro->bound && dev) {
628 if (dev->reg_state != NETREG_REGISTERED) {
629 err = -ENODEV;
630 goto out_err;
631 }
632 }
633
634 /* remove current error mask */
635 if (ro->bound) {
636 /* (try to) register the new err_mask */
637 err = raw_enable_errfilter(sock_net(sk), dev, sk,
638 err_mask);
639
640 if (err)
641 goto out_err;
642
643 /* remove old err_mask registration */
644 raw_disable_errfilter(sock_net(sk), dev, sk,
645 ro->err_mask);
646 }
647
648 /* link new err_mask to the socket */
649 ro->err_mask = err_mask;
650
651 out_err:
652 release_sock(sk);
653 rtnl_unlock();
654
655 break;
656
657 case CAN_RAW_LOOPBACK:
658 if (optlen != sizeof(ro->loopback))
659 return -EINVAL;
660
661 if (copy_from_sockptr(&ro->loopback, optval, optlen))
662 return -EFAULT;
663
664 break;
665
666 case CAN_RAW_RECV_OWN_MSGS:
667 if (optlen != sizeof(ro->recv_own_msgs))
668 return -EINVAL;
669
670 if (copy_from_sockptr(&ro->recv_own_msgs, optval, optlen))
671 return -EFAULT;
672
673 break;
674
675 case CAN_RAW_FD_FRAMES:
676 if (optlen != sizeof(fd_frames))
677 return -EINVAL;
678
679 if (copy_from_sockptr(&fd_frames, optval, optlen))
680 return -EFAULT;
681
682 /* Enabling CAN XL includes CAN FD */
683 if (ro->xl_frames && !fd_frames)
684 return -EINVAL;
685
686 ro->fd_frames = fd_frames;
687 break;
688
689 case CAN_RAW_XL_FRAMES:
690 if (optlen != sizeof(ro->xl_frames))
691 return -EINVAL;
692
693 if (copy_from_sockptr(&ro->xl_frames, optval, optlen))
694 return -EFAULT;
695
696 /* Enabling CAN XL includes CAN FD */
697 if (ro->xl_frames)
698 ro->fd_frames = ro->xl_frames;
699 break;
700
701 case CAN_RAW_JOIN_FILTERS:
702 if (optlen != sizeof(ro->join_filters))
703 return -EINVAL;
704
705 if (copy_from_sockptr(&ro->join_filters, optval, optlen))
706 return -EFAULT;
707
708 break;
709
710 default:
711 return -ENOPROTOOPT;
712 }
713 return err;
714}
715
716static int raw_getsockopt(struct socket *sock, int level, int optname,
717 char __user *optval, int __user *optlen)
718{
719 struct sock *sk = sock->sk;
720 struct raw_sock *ro = raw_sk(sk);
721 int len;
722 void *val;
723 int err = 0;
724
725 if (level != SOL_CAN_RAW)
726 return -EINVAL;
727 if (get_user(len, optlen))
728 return -EFAULT;
729 if (len < 0)
730 return -EINVAL;
731
732 switch (optname) {
733 case CAN_RAW_FILTER:
734 lock_sock(sk);
735 if (ro->count > 0) {
736 int fsize = ro->count * sizeof(struct can_filter);
737
738 /* user space buffer to small for filter list? */
739 if (len < fsize) {
740 /* return -ERANGE and needed space in optlen */
741 err = -ERANGE;
742 if (put_user(fsize, optlen))
743 err = -EFAULT;
744 } else {
745 if (len > fsize)
746 len = fsize;
747 if (copy_to_user(optval, ro->filter, len))
748 err = -EFAULT;
749 }
750 } else {
751 len = 0;
752 }
753 release_sock(sk);
754
755 if (!err)
756 err = put_user(len, optlen);
757 return err;
758
759 case CAN_RAW_ERR_FILTER:
760 if (len > sizeof(can_err_mask_t))
761 len = sizeof(can_err_mask_t);
762 val = &ro->err_mask;
763 break;
764
765 case CAN_RAW_LOOPBACK:
766 if (len > sizeof(int))
767 len = sizeof(int);
768 val = &ro->loopback;
769 break;
770
771 case CAN_RAW_RECV_OWN_MSGS:
772 if (len > sizeof(int))
773 len = sizeof(int);
774 val = &ro->recv_own_msgs;
775 break;
776
777 case CAN_RAW_FD_FRAMES:
778 if (len > sizeof(int))
779 len = sizeof(int);
780 val = &ro->fd_frames;
781 break;
782
783 case CAN_RAW_XL_FRAMES:
784 if (len > sizeof(int))
785 len = sizeof(int);
786 val = &ro->xl_frames;
787 break;
788
789 case CAN_RAW_JOIN_FILTERS:
790 if (len > sizeof(int))
791 len = sizeof(int);
792 val = &ro->join_filters;
793 break;
794
795 default:
796 return -ENOPROTOOPT;
797 }
798
799 if (put_user(len, optlen))
800 return -EFAULT;
801 if (copy_to_user(optval, val, len))
802 return -EFAULT;
803 return 0;
804}
805
806static bool raw_bad_txframe(struct raw_sock *ro, struct sk_buff *skb, int mtu)
807{
808 /* Classical CAN -> no checks for flags and device capabilities */
809 if (can_is_can_skb(skb))
810 return false;
811
812 /* CAN FD -> needs to be enabled and a CAN FD or CAN XL device */
813 if (ro->fd_frames && can_is_canfd_skb(skb) &&
814 (mtu == CANFD_MTU || can_is_canxl_dev_mtu(mtu)))
815 return false;
816
817 /* CAN XL -> needs to be enabled and a CAN XL device */
818 if (ro->xl_frames && can_is_canxl_skb(skb) &&
819 can_is_canxl_dev_mtu(mtu))
820 return false;
821
822 return true;
823}
824
825static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
826{
827 struct sock *sk = sock->sk;
828 struct raw_sock *ro = raw_sk(sk);
829 struct sockcm_cookie sockc;
830 struct sk_buff *skb;
831 struct net_device *dev;
832 int ifindex;
833 int err = -EINVAL;
834
835 /* check for valid CAN frame sizes */
836 if (size < CANXL_HDR_SIZE + CANXL_MIN_DLEN || size > CANXL_MTU)
837 return -EINVAL;
838
839 if (msg->msg_name) {
840 DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name);
841
842 if (msg->msg_namelen < RAW_MIN_NAMELEN)
843 return -EINVAL;
844
845 if (addr->can_family != AF_CAN)
846 return -EINVAL;
847
848 ifindex = addr->can_ifindex;
849 } else {
850 ifindex = ro->ifindex;
851 }
852
853 dev = dev_get_by_index(sock_net(sk), ifindex);
854 if (!dev)
855 return -ENXIO;
856
857 skb = sock_alloc_send_skb(sk, size + sizeof(struct can_skb_priv),
858 msg->msg_flags & MSG_DONTWAIT, &err);
859 if (!skb)
860 goto put_dev;
861
862 can_skb_reserve(skb);
863 can_skb_prv(skb)->ifindex = dev->ifindex;
864 can_skb_prv(skb)->skbcnt = 0;
865
866 /* fill the skb before testing for valid CAN frames */
867 err = memcpy_from_msg(skb_put(skb, size), msg, size);
868 if (err < 0)
869 goto free_skb;
870
871 err = -EINVAL;
872 if (raw_bad_txframe(ro, skb, dev->mtu))
873 goto free_skb;
874
875 sockcm_init(&sockc, sk);
876 if (msg->msg_controllen) {
877 err = sock_cmsg_send(sk, msg, &sockc);
878 if (unlikely(err))
879 goto free_skb;
880 }
881
882 skb->dev = dev;
883 skb->priority = READ_ONCE(sk->sk_priority);
884 skb->mark = READ_ONCE(sk->sk_mark);
885 skb->tstamp = sockc.transmit_time;
886
887 skb_setup_tx_timestamp(skb, sockc.tsflags);
888
889 err = can_send(skb, ro->loopback);
890
891 dev_put(dev);
892
893 if (err)
894 goto send_failed;
895
896 return size;
897
898free_skb:
899 kfree_skb(skb);
900put_dev:
901 dev_put(dev);
902send_failed:
903 return err;
904}
905
906static int raw_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
907 int flags)
908{
909 struct sock *sk = sock->sk;
910 struct sk_buff *skb;
911 int err = 0;
912
913 if (flags & MSG_ERRQUEUE)
914 return sock_recv_errqueue(sk, msg, size,
915 SOL_CAN_RAW, SCM_CAN_RAW_ERRQUEUE);
916
917 skb = skb_recv_datagram(sk, flags, &err);
918 if (!skb)
919 return err;
920
921 if (size < skb->len)
922 msg->msg_flags |= MSG_TRUNC;
923 else
924 size = skb->len;
925
926 err = memcpy_to_msg(msg, skb->data, size);
927 if (err < 0) {
928 skb_free_datagram(sk, skb);
929 return err;
930 }
931
932 sock_recv_cmsgs(msg, sk, skb);
933
934 if (msg->msg_name) {
935 __sockaddr_check_size(RAW_MIN_NAMELEN);
936 msg->msg_namelen = RAW_MIN_NAMELEN;
937 memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
938 }
939
940 /* assign the flags that have been recorded in raw_rcv() */
941 msg->msg_flags |= *(raw_flags(skb));
942
943 skb_free_datagram(sk, skb);
944
945 return size;
946}
947
948static int raw_sock_no_ioctlcmd(struct socket *sock, unsigned int cmd,
949 unsigned long arg)
950{
951 /* no ioctls for socket layer -> hand it down to NIC layer */
952 return -ENOIOCTLCMD;
953}
954
955static const struct proto_ops raw_ops = {
956 .family = PF_CAN,
957 .release = raw_release,
958 .bind = raw_bind,
959 .connect = sock_no_connect,
960 .socketpair = sock_no_socketpair,
961 .accept = sock_no_accept,
962 .getname = raw_getname,
963 .poll = datagram_poll,
964 .ioctl = raw_sock_no_ioctlcmd,
965 .gettstamp = sock_gettstamp,
966 .listen = sock_no_listen,
967 .shutdown = sock_no_shutdown,
968 .setsockopt = raw_setsockopt,
969 .getsockopt = raw_getsockopt,
970 .sendmsg = raw_sendmsg,
971 .recvmsg = raw_recvmsg,
972 .mmap = sock_no_mmap,
973};
974
975static struct proto raw_proto __read_mostly = {
976 .name = "CAN_RAW",
977 .owner = THIS_MODULE,
978 .obj_size = sizeof(struct raw_sock),
979 .init = raw_init,
980};
981
982static const struct can_proto raw_can_proto = {
983 .type = SOCK_RAW,
984 .protocol = CAN_RAW,
985 .ops = &raw_ops,
986 .prot = &raw_proto,
987};
988
989static struct notifier_block canraw_notifier = {
990 .notifier_call = raw_notifier
991};
992
993static __init int raw_module_init(void)
994{
995 int err;
996
997 pr_info("can: raw protocol\n");
998
999 err = register_netdevice_notifier(&canraw_notifier);
1000 if (err)
1001 return err;
1002
1003 err = can_proto_register(&raw_can_proto);
1004 if (err < 0) {
1005 pr_err("can: registration of raw protocol failed\n");
1006 goto register_proto_failed;
1007 }
1008
1009 return 0;
1010
1011register_proto_failed:
1012 unregister_netdevice_notifier(&canraw_notifier);
1013 return err;
1014}
1015
1016static __exit void raw_module_exit(void)
1017{
1018 can_proto_unregister(&raw_can_proto);
1019 unregister_netdevice_notifier(&canraw_notifier);
1020}
1021
1022module_init(raw_module_init);
1023module_exit(raw_module_exit);