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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/skb.h>
54#include <linux/can/raw.h>
55#include <net/sock.h>
56#include <net/net_namespace.h>
57
58MODULE_DESCRIPTION("PF_CAN raw protocol");
59MODULE_LICENSE("Dual BSD/GPL");
60MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>");
61MODULE_ALIAS("can-proto-1");
62
63#define RAW_MIN_NAMELEN CAN_REQUIRED_SIZE(struct sockaddr_can, can_ifindex)
64
65#define MASK_ALL 0
66
67/* A raw socket has a list of can_filters attached to it, each receiving
68 * the CAN frames matching that filter. If the filter list is empty,
69 * no CAN frames will be received by the socket. The default after
70 * opening the socket, is to have one filter which receives all frames.
71 * The filter list is allocated dynamically with the exception of the
72 * list containing only one item. This common case is optimized by
73 * storing the single filter in dfilter, to avoid using dynamic memory.
74 */
75
76struct uniqframe {
77 int skbcnt;
78 const struct sk_buff *skb;
79 unsigned int join_rx_count;
80};
81
82struct raw_sock {
83 struct sock sk;
84 int bound;
85 int ifindex;
86 struct list_head notifier;
87 int loopback;
88 int recv_own_msgs;
89 int fd_frames;
90 int join_filters;
91 int count; /* number of active filters */
92 struct can_filter dfilter; /* default/single filter */
93 struct can_filter *filter; /* pointer to filter(s) */
94 can_err_mask_t err_mask;
95 struct uniqframe __percpu *uniq;
96};
97
98static LIST_HEAD(raw_notifier_list);
99static DEFINE_SPINLOCK(raw_notifier_lock);
100static struct raw_sock *raw_busy_notifier;
101
102/* Return pointer to store the extra msg flags for raw_recvmsg().
103 * We use the space of one unsigned int beyond the 'struct sockaddr_can'
104 * in skb->cb.
105 */
106static inline unsigned int *raw_flags(struct sk_buff *skb)
107{
108 sock_skb_cb_check_size(sizeof(struct sockaddr_can) +
109 sizeof(unsigned int));
110
111 /* return pointer after struct sockaddr_can */
112 return (unsigned int *)(&((struct sockaddr_can *)skb->cb)[1]);
113}
114
115static inline struct raw_sock *raw_sk(const struct sock *sk)
116{
117 return (struct raw_sock *)sk;
118}
119
120static void raw_rcv(struct sk_buff *oskb, void *data)
121{
122 struct sock *sk = (struct sock *)data;
123 struct raw_sock *ro = raw_sk(sk);
124 struct sockaddr_can *addr;
125 struct sk_buff *skb;
126 unsigned int *pflags;
127
128 /* check the received tx sock reference */
129 if (!ro->recv_own_msgs && oskb->sk == sk)
130 return;
131
132 /* do not pass non-CAN2.0 frames to a legacy socket */
133 if (!ro->fd_frames && oskb->len != CAN_MTU)
134 return;
135
136 /* eliminate multiple filter matches for the same skb */
137 if (this_cpu_ptr(ro->uniq)->skb == oskb &&
138 this_cpu_ptr(ro->uniq)->skbcnt == can_skb_prv(oskb)->skbcnt) {
139 if (ro->join_filters) {
140 this_cpu_inc(ro->uniq->join_rx_count);
141 /* drop frame until all enabled filters matched */
142 if (this_cpu_ptr(ro->uniq)->join_rx_count < ro->count)
143 return;
144 } else {
145 return;
146 }
147 } else {
148 this_cpu_ptr(ro->uniq)->skb = oskb;
149 this_cpu_ptr(ro->uniq)->skbcnt = can_skb_prv(oskb)->skbcnt;
150 this_cpu_ptr(ro->uniq)->join_rx_count = 1;
151 /* drop first frame to check all enabled filters? */
152 if (ro->join_filters && ro->count > 1)
153 return;
154 }
155
156 /* clone the given skb to be able to enqueue it into the rcv queue */
157 skb = skb_clone(oskb, GFP_ATOMIC);
158 if (!skb)
159 return;
160
161 /* Put the datagram to the queue so that raw_recvmsg() can get
162 * it from there. We need to pass the interface index to
163 * raw_recvmsg(). We pass a whole struct sockaddr_can in
164 * skb->cb containing the interface index.
165 */
166
167 sock_skb_cb_check_size(sizeof(struct sockaddr_can));
168 addr = (struct sockaddr_can *)skb->cb;
169 memset(addr, 0, sizeof(*addr));
170 addr->can_family = AF_CAN;
171 addr->can_ifindex = skb->dev->ifindex;
172
173 /* add CAN specific message flags for raw_recvmsg() */
174 pflags = raw_flags(skb);
175 *pflags = 0;
176 if (oskb->sk)
177 *pflags |= MSG_DONTROUTE;
178 if (oskb->sk == sk)
179 *pflags |= MSG_CONFIRM;
180
181 if (sock_queue_rcv_skb(sk, skb) < 0)
182 kfree_skb(skb);
183}
184
185static int raw_enable_filters(struct net *net, struct net_device *dev,
186 struct sock *sk, struct can_filter *filter,
187 int count)
188{
189 int err = 0;
190 int i;
191
192 for (i = 0; i < count; i++) {
193 err = can_rx_register(net, dev, filter[i].can_id,
194 filter[i].can_mask,
195 raw_rcv, sk, "raw", sk);
196 if (err) {
197 /* clean up successfully registered filters */
198 while (--i >= 0)
199 can_rx_unregister(net, dev, filter[i].can_id,
200 filter[i].can_mask,
201 raw_rcv, sk);
202 break;
203 }
204 }
205
206 return err;
207}
208
209static int raw_enable_errfilter(struct net *net, struct net_device *dev,
210 struct sock *sk, can_err_mask_t err_mask)
211{
212 int err = 0;
213
214 if (err_mask)
215 err = can_rx_register(net, dev, 0, err_mask | CAN_ERR_FLAG,
216 raw_rcv, sk, "raw", sk);
217
218 return err;
219}
220
221static void raw_disable_filters(struct net *net, struct net_device *dev,
222 struct sock *sk, struct can_filter *filter,
223 int count)
224{
225 int i;
226
227 for (i = 0; i < count; i++)
228 can_rx_unregister(net, dev, filter[i].can_id,
229 filter[i].can_mask, raw_rcv, sk);
230}
231
232static inline void raw_disable_errfilter(struct net *net,
233 struct net_device *dev,
234 struct sock *sk,
235 can_err_mask_t err_mask)
236
237{
238 if (err_mask)
239 can_rx_unregister(net, dev, 0, err_mask | CAN_ERR_FLAG,
240 raw_rcv, sk);
241}
242
243static inline void raw_disable_allfilters(struct net *net,
244 struct net_device *dev,
245 struct sock *sk)
246{
247 struct raw_sock *ro = raw_sk(sk);
248
249 raw_disable_filters(net, dev, sk, ro->filter, ro->count);
250 raw_disable_errfilter(net, dev, sk, ro->err_mask);
251}
252
253static int raw_enable_allfilters(struct net *net, struct net_device *dev,
254 struct sock *sk)
255{
256 struct raw_sock *ro = raw_sk(sk);
257 int err;
258
259 err = raw_enable_filters(net, dev, sk, ro->filter, ro->count);
260 if (!err) {
261 err = raw_enable_errfilter(net, dev, sk, ro->err_mask);
262 if (err)
263 raw_disable_filters(net, dev, sk, ro->filter,
264 ro->count);
265 }
266
267 return err;
268}
269
270static void raw_notify(struct raw_sock *ro, unsigned long msg,
271 struct net_device *dev)
272{
273 struct sock *sk = &ro->sk;
274
275 if (!net_eq(dev_net(dev), sock_net(sk)))
276 return;
277
278 if (ro->ifindex != dev->ifindex)
279 return;
280
281 switch (msg) {
282 case NETDEV_UNREGISTER:
283 lock_sock(sk);
284 /* remove current filters & unregister */
285 if (ro->bound)
286 raw_disable_allfilters(dev_net(dev), dev, sk);
287
288 if (ro->count > 1)
289 kfree(ro->filter);
290
291 ro->ifindex = 0;
292 ro->bound = 0;
293 ro->count = 0;
294 release_sock(sk);
295
296 sk->sk_err = ENODEV;
297 if (!sock_flag(sk, SOCK_DEAD))
298 sk_error_report(sk);
299 break;
300
301 case NETDEV_DOWN:
302 sk->sk_err = ENETDOWN;
303 if (!sock_flag(sk, SOCK_DEAD))
304 sk_error_report(sk);
305 break;
306 }
307}
308
309static int raw_notifier(struct notifier_block *nb, unsigned long msg,
310 void *ptr)
311{
312 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
313
314 if (dev->type != ARPHRD_CAN)
315 return NOTIFY_DONE;
316 if (msg != NETDEV_UNREGISTER && msg != NETDEV_DOWN)
317 return NOTIFY_DONE;
318 if (unlikely(raw_busy_notifier)) /* Check for reentrant bug. */
319 return NOTIFY_DONE;
320
321 spin_lock(&raw_notifier_lock);
322 list_for_each_entry(raw_busy_notifier, &raw_notifier_list, notifier) {
323 spin_unlock(&raw_notifier_lock);
324 raw_notify(raw_busy_notifier, msg, dev);
325 spin_lock(&raw_notifier_lock);
326 }
327 raw_busy_notifier = NULL;
328 spin_unlock(&raw_notifier_lock);
329 return NOTIFY_DONE;
330}
331
332static int raw_init(struct sock *sk)
333{
334 struct raw_sock *ro = raw_sk(sk);
335
336 ro->bound = 0;
337 ro->ifindex = 0;
338
339 /* set default filter to single entry dfilter */
340 ro->dfilter.can_id = 0;
341 ro->dfilter.can_mask = MASK_ALL;
342 ro->filter = &ro->dfilter;
343 ro->count = 1;
344
345 /* set default loopback behaviour */
346 ro->loopback = 1;
347 ro->recv_own_msgs = 0;
348 ro->fd_frames = 0;
349 ro->join_filters = 0;
350
351 /* alloc_percpu provides zero'ed memory */
352 ro->uniq = alloc_percpu(struct uniqframe);
353 if (unlikely(!ro->uniq))
354 return -ENOMEM;
355
356 /* set notifier */
357 spin_lock(&raw_notifier_lock);
358 list_add_tail(&ro->notifier, &raw_notifier_list);
359 spin_unlock(&raw_notifier_lock);
360
361 return 0;
362}
363
364static int raw_release(struct socket *sock)
365{
366 struct sock *sk = sock->sk;
367 struct raw_sock *ro;
368
369 if (!sk)
370 return 0;
371
372 ro = raw_sk(sk);
373
374 spin_lock(&raw_notifier_lock);
375 while (raw_busy_notifier == ro) {
376 spin_unlock(&raw_notifier_lock);
377 schedule_timeout_uninterruptible(1);
378 spin_lock(&raw_notifier_lock);
379 }
380 list_del(&ro->notifier);
381 spin_unlock(&raw_notifier_lock);
382
383 lock_sock(sk);
384
385 /* remove current filters & unregister */
386 if (ro->bound) {
387 if (ro->ifindex) {
388 struct net_device *dev;
389
390 dev = dev_get_by_index(sock_net(sk), ro->ifindex);
391 if (dev) {
392 raw_disable_allfilters(dev_net(dev), dev, sk);
393 dev_put(dev);
394 }
395 } else {
396 raw_disable_allfilters(sock_net(sk), NULL, sk);
397 }
398 }
399
400 if (ro->count > 1)
401 kfree(ro->filter);
402
403 ro->ifindex = 0;
404 ro->bound = 0;
405 ro->count = 0;
406 free_percpu(ro->uniq);
407
408 sock_orphan(sk);
409 sock->sk = NULL;
410
411 release_sock(sk);
412 sock_put(sk);
413
414 return 0;
415}
416
417static int raw_bind(struct socket *sock, struct sockaddr *uaddr, int len)
418{
419 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
420 struct sock *sk = sock->sk;
421 struct raw_sock *ro = raw_sk(sk);
422 int ifindex;
423 int err = 0;
424 int notify_enetdown = 0;
425
426 if (len < RAW_MIN_NAMELEN)
427 return -EINVAL;
428 if (addr->can_family != AF_CAN)
429 return -EINVAL;
430
431 lock_sock(sk);
432
433 if (ro->bound && addr->can_ifindex == ro->ifindex)
434 goto out;
435
436 if (addr->can_ifindex) {
437 struct net_device *dev;
438
439 dev = dev_get_by_index(sock_net(sk), addr->can_ifindex);
440 if (!dev) {
441 err = -ENODEV;
442 goto out;
443 }
444 if (dev->type != ARPHRD_CAN) {
445 dev_put(dev);
446 err = -ENODEV;
447 goto out;
448 }
449 if (!(dev->flags & IFF_UP))
450 notify_enetdown = 1;
451
452 ifindex = dev->ifindex;
453
454 /* filters set by default/setsockopt */
455 err = raw_enable_allfilters(sock_net(sk), dev, sk);
456 dev_put(dev);
457 } else {
458 ifindex = 0;
459
460 /* filters set by default/setsockopt */
461 err = raw_enable_allfilters(sock_net(sk), NULL, sk);
462 }
463
464 if (!err) {
465 if (ro->bound) {
466 /* unregister old filters */
467 if (ro->ifindex) {
468 struct net_device *dev;
469
470 dev = dev_get_by_index(sock_net(sk),
471 ro->ifindex);
472 if (dev) {
473 raw_disable_allfilters(dev_net(dev),
474 dev, sk);
475 dev_put(dev);
476 }
477 } else {
478 raw_disable_allfilters(sock_net(sk), NULL, sk);
479 }
480 }
481 ro->ifindex = ifindex;
482 ro->bound = 1;
483 }
484
485 out:
486 release_sock(sk);
487
488 if (notify_enetdown) {
489 sk->sk_err = ENETDOWN;
490 if (!sock_flag(sk, SOCK_DEAD))
491 sk_error_report(sk);
492 }
493
494 return err;
495}
496
497static int raw_getname(struct socket *sock, struct sockaddr *uaddr,
498 int peer)
499{
500 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
501 struct sock *sk = sock->sk;
502 struct raw_sock *ro = raw_sk(sk);
503
504 if (peer)
505 return -EOPNOTSUPP;
506
507 memset(addr, 0, RAW_MIN_NAMELEN);
508 addr->can_family = AF_CAN;
509 addr->can_ifindex = ro->ifindex;
510
511 return RAW_MIN_NAMELEN;
512}
513
514static int raw_setsockopt(struct socket *sock, int level, int optname,
515 sockptr_t optval, unsigned int optlen)
516{
517 struct sock *sk = sock->sk;
518 struct raw_sock *ro = raw_sk(sk);
519 struct can_filter *filter = NULL; /* dyn. alloc'ed filters */
520 struct can_filter sfilter; /* single filter */
521 struct net_device *dev = NULL;
522 can_err_mask_t err_mask = 0;
523 int count = 0;
524 int err = 0;
525
526 if (level != SOL_CAN_RAW)
527 return -EINVAL;
528
529 switch (optname) {
530 case CAN_RAW_FILTER:
531 if (optlen % sizeof(struct can_filter) != 0)
532 return -EINVAL;
533
534 if (optlen > CAN_RAW_FILTER_MAX * sizeof(struct can_filter))
535 return -EINVAL;
536
537 count = optlen / sizeof(struct can_filter);
538
539 if (count > 1) {
540 /* filter does not fit into dfilter => alloc space */
541 filter = memdup_sockptr(optval, optlen);
542 if (IS_ERR(filter))
543 return PTR_ERR(filter);
544 } else if (count == 1) {
545 if (copy_from_sockptr(&sfilter, optval, sizeof(sfilter)))
546 return -EFAULT;
547 }
548
549 rtnl_lock();
550 lock_sock(sk);
551
552 if (ro->bound && ro->ifindex) {
553 dev = dev_get_by_index(sock_net(sk), ro->ifindex);
554 if (!dev) {
555 if (count > 1)
556 kfree(filter);
557 err = -ENODEV;
558 goto out_fil;
559 }
560 }
561
562 if (ro->bound) {
563 /* (try to) register the new filters */
564 if (count == 1)
565 err = raw_enable_filters(sock_net(sk), dev, sk,
566 &sfilter, 1);
567 else
568 err = raw_enable_filters(sock_net(sk), dev, sk,
569 filter, count);
570 if (err) {
571 if (count > 1)
572 kfree(filter);
573 goto out_fil;
574 }
575
576 /* remove old filter registrations */
577 raw_disable_filters(sock_net(sk), dev, sk, ro->filter,
578 ro->count);
579 }
580
581 /* remove old filter space */
582 if (ro->count > 1)
583 kfree(ro->filter);
584
585 /* link new filters to the socket */
586 if (count == 1) {
587 /* copy filter data for single filter */
588 ro->dfilter = sfilter;
589 filter = &ro->dfilter;
590 }
591 ro->filter = filter;
592 ro->count = count;
593
594 out_fil:
595 if (dev)
596 dev_put(dev);
597
598 release_sock(sk);
599 rtnl_unlock();
600
601 break;
602
603 case CAN_RAW_ERR_FILTER:
604 if (optlen != sizeof(err_mask))
605 return -EINVAL;
606
607 if (copy_from_sockptr(&err_mask, optval, optlen))
608 return -EFAULT;
609
610 err_mask &= CAN_ERR_MASK;
611
612 rtnl_lock();
613 lock_sock(sk);
614
615 if (ro->bound && ro->ifindex) {
616 dev = dev_get_by_index(sock_net(sk), ro->ifindex);
617 if (!dev) {
618 err = -ENODEV;
619 goto out_err;
620 }
621 }
622
623 /* remove current error mask */
624 if (ro->bound) {
625 /* (try to) register the new err_mask */
626 err = raw_enable_errfilter(sock_net(sk), dev, sk,
627 err_mask);
628
629 if (err)
630 goto out_err;
631
632 /* remove old err_mask registration */
633 raw_disable_errfilter(sock_net(sk), dev, sk,
634 ro->err_mask);
635 }
636
637 /* link new err_mask to the socket */
638 ro->err_mask = err_mask;
639
640 out_err:
641 if (dev)
642 dev_put(dev);
643
644 release_sock(sk);
645 rtnl_unlock();
646
647 break;
648
649 case CAN_RAW_LOOPBACK:
650 if (optlen != sizeof(ro->loopback))
651 return -EINVAL;
652
653 if (copy_from_sockptr(&ro->loopback, optval, optlen))
654 return -EFAULT;
655
656 break;
657
658 case CAN_RAW_RECV_OWN_MSGS:
659 if (optlen != sizeof(ro->recv_own_msgs))
660 return -EINVAL;
661
662 if (copy_from_sockptr(&ro->recv_own_msgs, optval, optlen))
663 return -EFAULT;
664
665 break;
666
667 case CAN_RAW_FD_FRAMES:
668 if (optlen != sizeof(ro->fd_frames))
669 return -EINVAL;
670
671 if (copy_from_sockptr(&ro->fd_frames, optval, optlen))
672 return -EFAULT;
673
674 break;
675
676 case CAN_RAW_JOIN_FILTERS:
677 if (optlen != sizeof(ro->join_filters))
678 return -EINVAL;
679
680 if (copy_from_sockptr(&ro->join_filters, optval, optlen))
681 return -EFAULT;
682
683 break;
684
685 default:
686 return -ENOPROTOOPT;
687 }
688 return err;
689}
690
691static int raw_getsockopt(struct socket *sock, int level, int optname,
692 char __user *optval, int __user *optlen)
693{
694 struct sock *sk = sock->sk;
695 struct raw_sock *ro = raw_sk(sk);
696 int len;
697 void *val;
698 int err = 0;
699
700 if (level != SOL_CAN_RAW)
701 return -EINVAL;
702 if (get_user(len, optlen))
703 return -EFAULT;
704 if (len < 0)
705 return -EINVAL;
706
707 switch (optname) {
708 case CAN_RAW_FILTER:
709 lock_sock(sk);
710 if (ro->count > 0) {
711 int fsize = ro->count * sizeof(struct can_filter);
712
713 /* user space buffer to small for filter list? */
714 if (len < fsize) {
715 /* return -ERANGE and needed space in optlen */
716 err = -ERANGE;
717 if (put_user(fsize, optlen))
718 err = -EFAULT;
719 } else {
720 if (len > fsize)
721 len = fsize;
722 if (copy_to_user(optval, ro->filter, len))
723 err = -EFAULT;
724 }
725 } else {
726 len = 0;
727 }
728 release_sock(sk);
729
730 if (!err)
731 err = put_user(len, optlen);
732 return err;
733
734 case CAN_RAW_ERR_FILTER:
735 if (len > sizeof(can_err_mask_t))
736 len = sizeof(can_err_mask_t);
737 val = &ro->err_mask;
738 break;
739
740 case CAN_RAW_LOOPBACK:
741 if (len > sizeof(int))
742 len = sizeof(int);
743 val = &ro->loopback;
744 break;
745
746 case CAN_RAW_RECV_OWN_MSGS:
747 if (len > sizeof(int))
748 len = sizeof(int);
749 val = &ro->recv_own_msgs;
750 break;
751
752 case CAN_RAW_FD_FRAMES:
753 if (len > sizeof(int))
754 len = sizeof(int);
755 val = &ro->fd_frames;
756 break;
757
758 case CAN_RAW_JOIN_FILTERS:
759 if (len > sizeof(int))
760 len = sizeof(int);
761 val = &ro->join_filters;
762 break;
763
764 default:
765 return -ENOPROTOOPT;
766 }
767
768 if (put_user(len, optlen))
769 return -EFAULT;
770 if (copy_to_user(optval, val, len))
771 return -EFAULT;
772 return 0;
773}
774
775static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
776{
777 struct sock *sk = sock->sk;
778 struct raw_sock *ro = raw_sk(sk);
779 struct sk_buff *skb;
780 struct net_device *dev;
781 int ifindex;
782 int err;
783
784 if (msg->msg_name) {
785 DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name);
786
787 if (msg->msg_namelen < RAW_MIN_NAMELEN)
788 return -EINVAL;
789
790 if (addr->can_family != AF_CAN)
791 return -EINVAL;
792
793 ifindex = addr->can_ifindex;
794 } else {
795 ifindex = ro->ifindex;
796 }
797
798 dev = dev_get_by_index(sock_net(sk), ifindex);
799 if (!dev)
800 return -ENXIO;
801
802 err = -EINVAL;
803 if (ro->fd_frames && dev->mtu == CANFD_MTU) {
804 if (unlikely(size != CANFD_MTU && size != CAN_MTU))
805 goto put_dev;
806 } else {
807 if (unlikely(size != CAN_MTU))
808 goto put_dev;
809 }
810
811 skb = sock_alloc_send_skb(sk, size + sizeof(struct can_skb_priv),
812 msg->msg_flags & MSG_DONTWAIT, &err);
813 if (!skb)
814 goto put_dev;
815
816 can_skb_reserve(skb);
817 can_skb_prv(skb)->ifindex = dev->ifindex;
818 can_skb_prv(skb)->skbcnt = 0;
819
820 err = memcpy_from_msg(skb_put(skb, size), msg, size);
821 if (err < 0)
822 goto free_skb;
823
824 skb_setup_tx_timestamp(skb, sk->sk_tsflags);
825
826 skb->dev = dev;
827 skb->sk = sk;
828 skb->priority = sk->sk_priority;
829
830 err = can_send(skb, ro->loopback);
831
832 dev_put(dev);
833
834 if (err)
835 goto send_failed;
836
837 return size;
838
839free_skb:
840 kfree_skb(skb);
841put_dev:
842 dev_put(dev);
843send_failed:
844 return err;
845}
846
847static int raw_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
848 int flags)
849{
850 struct sock *sk = sock->sk;
851 struct sk_buff *skb;
852 int err = 0;
853 int noblock;
854
855 noblock = flags & MSG_DONTWAIT;
856 flags &= ~MSG_DONTWAIT;
857
858 if (flags & MSG_ERRQUEUE)
859 return sock_recv_errqueue(sk, msg, size,
860 SOL_CAN_RAW, SCM_CAN_RAW_ERRQUEUE);
861
862 skb = skb_recv_datagram(sk, flags, noblock, &err);
863 if (!skb)
864 return err;
865
866 if (size < skb->len)
867 msg->msg_flags |= MSG_TRUNC;
868 else
869 size = skb->len;
870
871 err = memcpy_to_msg(msg, skb->data, size);
872 if (err < 0) {
873 skb_free_datagram(sk, skb);
874 return err;
875 }
876
877 sock_recv_ts_and_drops(msg, sk, skb);
878
879 if (msg->msg_name) {
880 __sockaddr_check_size(RAW_MIN_NAMELEN);
881 msg->msg_namelen = RAW_MIN_NAMELEN;
882 memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
883 }
884
885 /* assign the flags that have been recorded in raw_rcv() */
886 msg->msg_flags |= *(raw_flags(skb));
887
888 skb_free_datagram(sk, skb);
889
890 return size;
891}
892
893static int raw_sock_no_ioctlcmd(struct socket *sock, unsigned int cmd,
894 unsigned long arg)
895{
896 /* no ioctls for socket layer -> hand it down to NIC layer */
897 return -ENOIOCTLCMD;
898}
899
900static const struct proto_ops raw_ops = {
901 .family = PF_CAN,
902 .release = raw_release,
903 .bind = raw_bind,
904 .connect = sock_no_connect,
905 .socketpair = sock_no_socketpair,
906 .accept = sock_no_accept,
907 .getname = raw_getname,
908 .poll = datagram_poll,
909 .ioctl = raw_sock_no_ioctlcmd,
910 .gettstamp = sock_gettstamp,
911 .listen = sock_no_listen,
912 .shutdown = sock_no_shutdown,
913 .setsockopt = raw_setsockopt,
914 .getsockopt = raw_getsockopt,
915 .sendmsg = raw_sendmsg,
916 .recvmsg = raw_recvmsg,
917 .mmap = sock_no_mmap,
918 .sendpage = sock_no_sendpage,
919};
920
921static struct proto raw_proto __read_mostly = {
922 .name = "CAN_RAW",
923 .owner = THIS_MODULE,
924 .obj_size = sizeof(struct raw_sock),
925 .init = raw_init,
926};
927
928static const struct can_proto raw_can_proto = {
929 .type = SOCK_RAW,
930 .protocol = CAN_RAW,
931 .ops = &raw_ops,
932 .prot = &raw_proto,
933};
934
935static struct notifier_block canraw_notifier = {
936 .notifier_call = raw_notifier
937};
938
939static __init int raw_module_init(void)
940{
941 int err;
942
943 pr_info("can: raw protocol\n");
944
945 err = can_proto_register(&raw_can_proto);
946 if (err < 0)
947 pr_err("can: registration of raw protocol failed\n");
948 else
949 register_netdevice_notifier(&canraw_notifier);
950
951 return err;
952}
953
954static __exit void raw_module_exit(void)
955{
956 can_proto_unregister(&raw_can_proto);
957 unregister_netdevice_notifier(&canraw_notifier);
958}
959
960module_init(raw_module_init);
961module_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);