Loading...
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 struct can_raw_vcid_options raw_vcid_opts;
95 canid_t tx_vcid_shifted;
96 canid_t rx_vcid_shifted;
97 canid_t rx_vcid_mask_shifted;
98 int join_filters;
99 int count; /* number of active filters */
100 struct can_filter dfilter; /* default/single filter */
101 struct can_filter *filter; /* pointer to filter(s) */
102 can_err_mask_t err_mask;
103 struct uniqframe __percpu *uniq;
104};
105
106static LIST_HEAD(raw_notifier_list);
107static DEFINE_SPINLOCK(raw_notifier_lock);
108static struct raw_sock *raw_busy_notifier;
109
110/* Return pointer to store the extra msg flags for raw_recvmsg().
111 * We use the space of one unsigned int beyond the 'struct sockaddr_can'
112 * in skb->cb.
113 */
114static inline unsigned int *raw_flags(struct sk_buff *skb)
115{
116 sock_skb_cb_check_size(sizeof(struct sockaddr_can) +
117 sizeof(unsigned int));
118
119 /* return pointer after struct sockaddr_can */
120 return (unsigned int *)(&((struct sockaddr_can *)skb->cb)[1]);
121}
122
123static inline struct raw_sock *raw_sk(const struct sock *sk)
124{
125 return (struct raw_sock *)sk;
126}
127
128static void raw_rcv(struct sk_buff *oskb, void *data)
129{
130 struct sock *sk = (struct sock *)data;
131 struct raw_sock *ro = raw_sk(sk);
132 struct sockaddr_can *addr;
133 struct sk_buff *skb;
134 unsigned int *pflags;
135
136 /* check the received tx sock reference */
137 if (!ro->recv_own_msgs && oskb->sk == sk)
138 return;
139
140 /* make sure to not pass oversized frames to the socket */
141 if (!ro->fd_frames && can_is_canfd_skb(oskb))
142 return;
143
144 if (can_is_canxl_skb(oskb)) {
145 struct canxl_frame *cxl = (struct canxl_frame *)oskb->data;
146
147 /* make sure to not pass oversized frames to the socket */
148 if (!ro->xl_frames)
149 return;
150
151 /* filter CAN XL VCID content */
152 if (ro->raw_vcid_opts.flags & CAN_RAW_XL_VCID_RX_FILTER) {
153 /* apply VCID filter if user enabled the filter */
154 if ((cxl->prio & ro->rx_vcid_mask_shifted) !=
155 (ro->rx_vcid_shifted & ro->rx_vcid_mask_shifted))
156 return;
157 } else {
158 /* no filter => do not forward VCID tagged frames */
159 if (cxl->prio & CANXL_VCID_MASK)
160 return;
161 }
162 }
163
164 /* eliminate multiple filter matches for the same skb */
165 if (this_cpu_ptr(ro->uniq)->skb == oskb &&
166 this_cpu_ptr(ro->uniq)->skbcnt == can_skb_prv(oskb)->skbcnt) {
167 if (!ro->join_filters)
168 return;
169
170 this_cpu_inc(ro->uniq->join_rx_count);
171 /* drop frame until all enabled filters matched */
172 if (this_cpu_ptr(ro->uniq)->join_rx_count < ro->count)
173 return;
174 } else {
175 this_cpu_ptr(ro->uniq)->skb = oskb;
176 this_cpu_ptr(ro->uniq)->skbcnt = can_skb_prv(oskb)->skbcnt;
177 this_cpu_ptr(ro->uniq)->join_rx_count = 1;
178 /* drop first frame to check all enabled filters? */
179 if (ro->join_filters && ro->count > 1)
180 return;
181 }
182
183 /* clone the given skb to be able to enqueue it into the rcv queue */
184 skb = skb_clone(oskb, GFP_ATOMIC);
185 if (!skb)
186 return;
187
188 /* Put the datagram to the queue so that raw_recvmsg() can get
189 * it from there. We need to pass the interface index to
190 * raw_recvmsg(). We pass a whole struct sockaddr_can in
191 * skb->cb containing the interface index.
192 */
193
194 sock_skb_cb_check_size(sizeof(struct sockaddr_can));
195 addr = (struct sockaddr_can *)skb->cb;
196 memset(addr, 0, sizeof(*addr));
197 addr->can_family = AF_CAN;
198 addr->can_ifindex = skb->dev->ifindex;
199
200 /* add CAN specific message flags for raw_recvmsg() */
201 pflags = raw_flags(skb);
202 *pflags = 0;
203 if (oskb->sk)
204 *pflags |= MSG_DONTROUTE;
205 if (oskb->sk == sk)
206 *pflags |= MSG_CONFIRM;
207
208 if (sock_queue_rcv_skb(sk, skb) < 0)
209 kfree_skb(skb);
210}
211
212static int raw_enable_filters(struct net *net, struct net_device *dev,
213 struct sock *sk, struct can_filter *filter,
214 int count)
215{
216 int err = 0;
217 int i;
218
219 for (i = 0; i < count; i++) {
220 err = can_rx_register(net, dev, filter[i].can_id,
221 filter[i].can_mask,
222 raw_rcv, sk, "raw", sk);
223 if (err) {
224 /* clean up successfully registered filters */
225 while (--i >= 0)
226 can_rx_unregister(net, dev, filter[i].can_id,
227 filter[i].can_mask,
228 raw_rcv, sk);
229 break;
230 }
231 }
232
233 return err;
234}
235
236static int raw_enable_errfilter(struct net *net, struct net_device *dev,
237 struct sock *sk, can_err_mask_t err_mask)
238{
239 int err = 0;
240
241 if (err_mask)
242 err = can_rx_register(net, dev, 0, err_mask | CAN_ERR_FLAG,
243 raw_rcv, sk, "raw", sk);
244
245 return err;
246}
247
248static void raw_disable_filters(struct net *net, struct net_device *dev,
249 struct sock *sk, struct can_filter *filter,
250 int count)
251{
252 int i;
253
254 for (i = 0; i < count; i++)
255 can_rx_unregister(net, dev, filter[i].can_id,
256 filter[i].can_mask, raw_rcv, sk);
257}
258
259static inline void raw_disable_errfilter(struct net *net,
260 struct net_device *dev,
261 struct sock *sk,
262 can_err_mask_t err_mask)
263
264{
265 if (err_mask)
266 can_rx_unregister(net, dev, 0, err_mask | CAN_ERR_FLAG,
267 raw_rcv, sk);
268}
269
270static inline void raw_disable_allfilters(struct net *net,
271 struct net_device *dev,
272 struct sock *sk)
273{
274 struct raw_sock *ro = raw_sk(sk);
275
276 raw_disable_filters(net, dev, sk, ro->filter, ro->count);
277 raw_disable_errfilter(net, dev, sk, ro->err_mask);
278}
279
280static int raw_enable_allfilters(struct net *net, struct net_device *dev,
281 struct sock *sk)
282{
283 struct raw_sock *ro = raw_sk(sk);
284 int err;
285
286 err = raw_enable_filters(net, dev, sk, ro->filter, ro->count);
287 if (!err) {
288 err = raw_enable_errfilter(net, dev, sk, ro->err_mask);
289 if (err)
290 raw_disable_filters(net, dev, sk, ro->filter,
291 ro->count);
292 }
293
294 return err;
295}
296
297static void raw_notify(struct raw_sock *ro, unsigned long msg,
298 struct net_device *dev)
299{
300 struct sock *sk = &ro->sk;
301
302 if (!net_eq(dev_net(dev), sock_net(sk)))
303 return;
304
305 if (ro->dev != dev)
306 return;
307
308 switch (msg) {
309 case NETDEV_UNREGISTER:
310 lock_sock(sk);
311 /* remove current filters & unregister */
312 if (ro->bound) {
313 raw_disable_allfilters(dev_net(dev), dev, sk);
314 netdev_put(dev, &ro->dev_tracker);
315 }
316
317 if (ro->count > 1)
318 kfree(ro->filter);
319
320 ro->ifindex = 0;
321 ro->bound = 0;
322 ro->dev = NULL;
323 ro->count = 0;
324 release_sock(sk);
325
326 sk->sk_err = ENODEV;
327 if (!sock_flag(sk, SOCK_DEAD))
328 sk_error_report(sk);
329 break;
330
331 case NETDEV_DOWN:
332 sk->sk_err = ENETDOWN;
333 if (!sock_flag(sk, SOCK_DEAD))
334 sk_error_report(sk);
335 break;
336 }
337}
338
339static int raw_notifier(struct notifier_block *nb, unsigned long msg,
340 void *ptr)
341{
342 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
343
344 if (dev->type != ARPHRD_CAN)
345 return NOTIFY_DONE;
346 if (msg != NETDEV_UNREGISTER && msg != NETDEV_DOWN)
347 return NOTIFY_DONE;
348 if (unlikely(raw_busy_notifier)) /* Check for reentrant bug. */
349 return NOTIFY_DONE;
350
351 spin_lock(&raw_notifier_lock);
352 list_for_each_entry(raw_busy_notifier, &raw_notifier_list, notifier) {
353 spin_unlock(&raw_notifier_lock);
354 raw_notify(raw_busy_notifier, msg, dev);
355 spin_lock(&raw_notifier_lock);
356 }
357 raw_busy_notifier = NULL;
358 spin_unlock(&raw_notifier_lock);
359 return NOTIFY_DONE;
360}
361
362static int raw_init(struct sock *sk)
363{
364 struct raw_sock *ro = raw_sk(sk);
365
366 ro->bound = 0;
367 ro->ifindex = 0;
368 ro->dev = NULL;
369
370 /* set default filter to single entry dfilter */
371 ro->dfilter.can_id = 0;
372 ro->dfilter.can_mask = MASK_ALL;
373 ro->filter = &ro->dfilter;
374 ro->count = 1;
375
376 /* set default loopback behaviour */
377 ro->loopback = 1;
378 ro->recv_own_msgs = 0;
379 ro->fd_frames = 0;
380 ro->xl_frames = 0;
381 ro->join_filters = 0;
382
383 /* alloc_percpu provides zero'ed memory */
384 ro->uniq = alloc_percpu(struct uniqframe);
385 if (unlikely(!ro->uniq))
386 return -ENOMEM;
387
388 /* set notifier */
389 spin_lock(&raw_notifier_lock);
390 list_add_tail(&ro->notifier, &raw_notifier_list);
391 spin_unlock(&raw_notifier_lock);
392
393 return 0;
394}
395
396static int raw_release(struct socket *sock)
397{
398 struct sock *sk = sock->sk;
399 struct raw_sock *ro;
400
401 if (!sk)
402 return 0;
403
404 ro = raw_sk(sk);
405
406 spin_lock(&raw_notifier_lock);
407 while (raw_busy_notifier == ro) {
408 spin_unlock(&raw_notifier_lock);
409 schedule_timeout_uninterruptible(1);
410 spin_lock(&raw_notifier_lock);
411 }
412 list_del(&ro->notifier);
413 spin_unlock(&raw_notifier_lock);
414
415 rtnl_lock();
416 lock_sock(sk);
417
418 /* remove current filters & unregister */
419 if (ro->bound) {
420 if (ro->dev) {
421 raw_disable_allfilters(dev_net(ro->dev), ro->dev, sk);
422 netdev_put(ro->dev, &ro->dev_tracker);
423 } else {
424 raw_disable_allfilters(sock_net(sk), NULL, sk);
425 }
426 }
427
428 if (ro->count > 1)
429 kfree(ro->filter);
430
431 ro->ifindex = 0;
432 ro->bound = 0;
433 ro->dev = NULL;
434 ro->count = 0;
435 free_percpu(ro->uniq);
436
437 sock_orphan(sk);
438 sock->sk = NULL;
439
440 release_sock(sk);
441 rtnl_unlock();
442
443 sock_put(sk);
444
445 return 0;
446}
447
448static int raw_bind(struct socket *sock, struct sockaddr *uaddr, int len)
449{
450 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
451 struct sock *sk = sock->sk;
452 struct raw_sock *ro = raw_sk(sk);
453 struct net_device *dev = NULL;
454 int ifindex;
455 int err = 0;
456 int notify_enetdown = 0;
457
458 if (len < RAW_MIN_NAMELEN)
459 return -EINVAL;
460 if (addr->can_family != AF_CAN)
461 return -EINVAL;
462
463 rtnl_lock();
464 lock_sock(sk);
465
466 if (ro->bound && addr->can_ifindex == ro->ifindex)
467 goto out;
468
469 if (addr->can_ifindex) {
470 dev = dev_get_by_index(sock_net(sk), addr->can_ifindex);
471 if (!dev) {
472 err = -ENODEV;
473 goto out;
474 }
475 if (dev->type != ARPHRD_CAN) {
476 err = -ENODEV;
477 goto out_put_dev;
478 }
479
480 if (!(dev->flags & IFF_UP))
481 notify_enetdown = 1;
482
483 ifindex = dev->ifindex;
484
485 /* filters set by default/setsockopt */
486 err = raw_enable_allfilters(sock_net(sk), dev, sk);
487 if (err)
488 goto out_put_dev;
489
490 } else {
491 ifindex = 0;
492
493 /* filters set by default/setsockopt */
494 err = raw_enable_allfilters(sock_net(sk), NULL, sk);
495 }
496
497 if (!err) {
498 if (ro->bound) {
499 /* unregister old filters */
500 if (ro->dev) {
501 raw_disable_allfilters(dev_net(ro->dev),
502 ro->dev, sk);
503 /* drop reference to old ro->dev */
504 netdev_put(ro->dev, &ro->dev_tracker);
505 } else {
506 raw_disable_allfilters(sock_net(sk), NULL, sk);
507 }
508 }
509 ro->ifindex = ifindex;
510 ro->bound = 1;
511 /* bind() ok -> hold a reference for new ro->dev */
512 ro->dev = dev;
513 if (ro->dev)
514 netdev_hold(ro->dev, &ro->dev_tracker, GFP_KERNEL);
515 }
516
517out_put_dev:
518 /* remove potential reference from dev_get_by_index() */
519 dev_put(dev);
520out:
521 release_sock(sk);
522 rtnl_unlock();
523
524 if (notify_enetdown) {
525 sk->sk_err = ENETDOWN;
526 if (!sock_flag(sk, SOCK_DEAD))
527 sk_error_report(sk);
528 }
529
530 return err;
531}
532
533static int raw_getname(struct socket *sock, struct sockaddr *uaddr,
534 int peer)
535{
536 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
537 struct sock *sk = sock->sk;
538 struct raw_sock *ro = raw_sk(sk);
539
540 if (peer)
541 return -EOPNOTSUPP;
542
543 memset(addr, 0, RAW_MIN_NAMELEN);
544 addr->can_family = AF_CAN;
545 addr->can_ifindex = ro->ifindex;
546
547 return RAW_MIN_NAMELEN;
548}
549
550static int raw_setsockopt(struct socket *sock, int level, int optname,
551 sockptr_t optval, unsigned int optlen)
552{
553 struct sock *sk = sock->sk;
554 struct raw_sock *ro = raw_sk(sk);
555 struct can_filter *filter = NULL; /* dyn. alloc'ed filters */
556 struct can_filter sfilter; /* single filter */
557 struct net_device *dev = NULL;
558 can_err_mask_t err_mask = 0;
559 int fd_frames;
560 int count = 0;
561 int err = 0;
562
563 if (level != SOL_CAN_RAW)
564 return -EINVAL;
565
566 switch (optname) {
567 case CAN_RAW_FILTER:
568 if (optlen % sizeof(struct can_filter) != 0)
569 return -EINVAL;
570
571 if (optlen > CAN_RAW_FILTER_MAX * sizeof(struct can_filter))
572 return -EINVAL;
573
574 count = optlen / sizeof(struct can_filter);
575
576 if (count > 1) {
577 /* filter does not fit into dfilter => alloc space */
578 filter = memdup_sockptr(optval, optlen);
579 if (IS_ERR(filter))
580 return PTR_ERR(filter);
581 } else if (count == 1) {
582 if (copy_from_sockptr(&sfilter, optval, sizeof(sfilter)))
583 return -EFAULT;
584 }
585
586 rtnl_lock();
587 lock_sock(sk);
588
589 dev = ro->dev;
590 if (ro->bound && dev) {
591 if (dev->reg_state != NETREG_REGISTERED) {
592 if (count > 1)
593 kfree(filter);
594 err = -ENODEV;
595 goto out_fil;
596 }
597 }
598
599 if (ro->bound) {
600 /* (try to) register the new filters */
601 if (count == 1)
602 err = raw_enable_filters(sock_net(sk), dev, sk,
603 &sfilter, 1);
604 else
605 err = raw_enable_filters(sock_net(sk), dev, sk,
606 filter, count);
607 if (err) {
608 if (count > 1)
609 kfree(filter);
610 goto out_fil;
611 }
612
613 /* remove old filter registrations */
614 raw_disable_filters(sock_net(sk), dev, sk, ro->filter,
615 ro->count);
616 }
617
618 /* remove old filter space */
619 if (ro->count > 1)
620 kfree(ro->filter);
621
622 /* link new filters to the socket */
623 if (count == 1) {
624 /* copy filter data for single filter */
625 ro->dfilter = sfilter;
626 filter = &ro->dfilter;
627 }
628 ro->filter = filter;
629 ro->count = count;
630
631 out_fil:
632 release_sock(sk);
633 rtnl_unlock();
634
635 break;
636
637 case CAN_RAW_ERR_FILTER:
638 if (optlen != sizeof(err_mask))
639 return -EINVAL;
640
641 if (copy_from_sockptr(&err_mask, optval, optlen))
642 return -EFAULT;
643
644 err_mask &= CAN_ERR_MASK;
645
646 rtnl_lock();
647 lock_sock(sk);
648
649 dev = ro->dev;
650 if (ro->bound && dev) {
651 if (dev->reg_state != NETREG_REGISTERED) {
652 err = -ENODEV;
653 goto out_err;
654 }
655 }
656
657 /* remove current error mask */
658 if (ro->bound) {
659 /* (try to) register the new err_mask */
660 err = raw_enable_errfilter(sock_net(sk), dev, sk,
661 err_mask);
662
663 if (err)
664 goto out_err;
665
666 /* remove old err_mask registration */
667 raw_disable_errfilter(sock_net(sk), dev, sk,
668 ro->err_mask);
669 }
670
671 /* link new err_mask to the socket */
672 ro->err_mask = err_mask;
673
674 out_err:
675 release_sock(sk);
676 rtnl_unlock();
677
678 break;
679
680 case CAN_RAW_LOOPBACK:
681 if (optlen != sizeof(ro->loopback))
682 return -EINVAL;
683
684 if (copy_from_sockptr(&ro->loopback, optval, optlen))
685 return -EFAULT;
686
687 break;
688
689 case CAN_RAW_RECV_OWN_MSGS:
690 if (optlen != sizeof(ro->recv_own_msgs))
691 return -EINVAL;
692
693 if (copy_from_sockptr(&ro->recv_own_msgs, optval, optlen))
694 return -EFAULT;
695
696 break;
697
698 case CAN_RAW_FD_FRAMES:
699 if (optlen != sizeof(fd_frames))
700 return -EINVAL;
701
702 if (copy_from_sockptr(&fd_frames, optval, optlen))
703 return -EFAULT;
704
705 /* Enabling CAN XL includes CAN FD */
706 if (ro->xl_frames && !fd_frames)
707 return -EINVAL;
708
709 ro->fd_frames = fd_frames;
710 break;
711
712 case CAN_RAW_XL_FRAMES:
713 if (optlen != sizeof(ro->xl_frames))
714 return -EINVAL;
715
716 if (copy_from_sockptr(&ro->xl_frames, optval, optlen))
717 return -EFAULT;
718
719 /* Enabling CAN XL includes CAN FD */
720 if (ro->xl_frames)
721 ro->fd_frames = ro->xl_frames;
722 break;
723
724 case CAN_RAW_XL_VCID_OPTS:
725 if (optlen != sizeof(ro->raw_vcid_opts))
726 return -EINVAL;
727
728 if (copy_from_sockptr(&ro->raw_vcid_opts, optval, optlen))
729 return -EFAULT;
730
731 /* prepare 32 bit values for handling in hot path */
732 ro->tx_vcid_shifted = ro->raw_vcid_opts.tx_vcid << CANXL_VCID_OFFSET;
733 ro->rx_vcid_shifted = ro->raw_vcid_opts.rx_vcid << CANXL_VCID_OFFSET;
734 ro->rx_vcid_mask_shifted = ro->raw_vcid_opts.rx_vcid_mask << CANXL_VCID_OFFSET;
735 break;
736
737 case CAN_RAW_JOIN_FILTERS:
738 if (optlen != sizeof(ro->join_filters))
739 return -EINVAL;
740
741 if (copy_from_sockptr(&ro->join_filters, optval, optlen))
742 return -EFAULT;
743
744 break;
745
746 default:
747 return -ENOPROTOOPT;
748 }
749 return err;
750}
751
752static int raw_getsockopt(struct socket *sock, int level, int optname,
753 char __user *optval, int __user *optlen)
754{
755 struct sock *sk = sock->sk;
756 struct raw_sock *ro = raw_sk(sk);
757 int len;
758 void *val;
759
760 if (level != SOL_CAN_RAW)
761 return -EINVAL;
762 if (get_user(len, optlen))
763 return -EFAULT;
764 if (len < 0)
765 return -EINVAL;
766
767 switch (optname) {
768 case CAN_RAW_FILTER: {
769 int err = 0;
770
771 lock_sock(sk);
772 if (ro->count > 0) {
773 int fsize = ro->count * sizeof(struct can_filter);
774
775 /* user space buffer to small for filter list? */
776 if (len < fsize) {
777 /* return -ERANGE and needed space in optlen */
778 err = -ERANGE;
779 if (put_user(fsize, optlen))
780 err = -EFAULT;
781 } else {
782 if (len > fsize)
783 len = fsize;
784 if (copy_to_user(optval, ro->filter, len))
785 err = -EFAULT;
786 }
787 } else {
788 len = 0;
789 }
790 release_sock(sk);
791
792 if (!err)
793 err = put_user(len, optlen);
794 return err;
795 }
796 case CAN_RAW_ERR_FILTER:
797 if (len > sizeof(can_err_mask_t))
798 len = sizeof(can_err_mask_t);
799 val = &ro->err_mask;
800 break;
801
802 case CAN_RAW_LOOPBACK:
803 if (len > sizeof(int))
804 len = sizeof(int);
805 val = &ro->loopback;
806 break;
807
808 case CAN_RAW_RECV_OWN_MSGS:
809 if (len > sizeof(int))
810 len = sizeof(int);
811 val = &ro->recv_own_msgs;
812 break;
813
814 case CAN_RAW_FD_FRAMES:
815 if (len > sizeof(int))
816 len = sizeof(int);
817 val = &ro->fd_frames;
818 break;
819
820 case CAN_RAW_XL_FRAMES:
821 if (len > sizeof(int))
822 len = sizeof(int);
823 val = &ro->xl_frames;
824 break;
825
826 case CAN_RAW_XL_VCID_OPTS: {
827 int err = 0;
828
829 /* user space buffer to small for VCID opts? */
830 if (len < sizeof(ro->raw_vcid_opts)) {
831 /* return -ERANGE and needed space in optlen */
832 err = -ERANGE;
833 if (put_user(sizeof(ro->raw_vcid_opts), optlen))
834 err = -EFAULT;
835 } else {
836 if (len > sizeof(ro->raw_vcid_opts))
837 len = sizeof(ro->raw_vcid_opts);
838 if (copy_to_user(optval, &ro->raw_vcid_opts, len))
839 err = -EFAULT;
840 }
841 if (!err)
842 err = put_user(len, optlen);
843 return err;
844 }
845 case CAN_RAW_JOIN_FILTERS:
846 if (len > sizeof(int))
847 len = sizeof(int);
848 val = &ro->join_filters;
849 break;
850
851 default:
852 return -ENOPROTOOPT;
853 }
854
855 if (put_user(len, optlen))
856 return -EFAULT;
857 if (copy_to_user(optval, val, len))
858 return -EFAULT;
859 return 0;
860}
861
862static void raw_put_canxl_vcid(struct raw_sock *ro, struct sk_buff *skb)
863{
864 struct canxl_frame *cxl = (struct canxl_frame *)skb->data;
865
866 /* sanitize non CAN XL bits */
867 cxl->prio &= (CANXL_PRIO_MASK | CANXL_VCID_MASK);
868
869 /* clear VCID in CAN XL frame if pass through is disabled */
870 if (!(ro->raw_vcid_opts.flags & CAN_RAW_XL_VCID_TX_PASS))
871 cxl->prio &= CANXL_PRIO_MASK;
872
873 /* set VCID in CAN XL frame if enabled */
874 if (ro->raw_vcid_opts.flags & CAN_RAW_XL_VCID_TX_SET) {
875 cxl->prio &= CANXL_PRIO_MASK;
876 cxl->prio |= ro->tx_vcid_shifted;
877 }
878}
879
880static unsigned int raw_check_txframe(struct raw_sock *ro, struct sk_buff *skb, int mtu)
881{
882 /* Classical CAN -> no checks for flags and device capabilities */
883 if (can_is_can_skb(skb))
884 return CAN_MTU;
885
886 /* CAN FD -> needs to be enabled and a CAN FD or CAN XL device */
887 if (ro->fd_frames && can_is_canfd_skb(skb) &&
888 (mtu == CANFD_MTU || can_is_canxl_dev_mtu(mtu)))
889 return CANFD_MTU;
890
891 /* CAN XL -> needs to be enabled and a CAN XL device */
892 if (ro->xl_frames && can_is_canxl_skb(skb) &&
893 can_is_canxl_dev_mtu(mtu))
894 return CANXL_MTU;
895
896 return 0;
897}
898
899static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
900{
901 struct sock *sk = sock->sk;
902 struct raw_sock *ro = raw_sk(sk);
903 struct sockcm_cookie sockc;
904 struct sk_buff *skb;
905 struct net_device *dev;
906 unsigned int txmtu;
907 int ifindex;
908 int err = -EINVAL;
909
910 /* check for valid CAN frame sizes */
911 if (size < CANXL_HDR_SIZE + CANXL_MIN_DLEN || size > CANXL_MTU)
912 return -EINVAL;
913
914 if (msg->msg_name) {
915 DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name);
916
917 if (msg->msg_namelen < RAW_MIN_NAMELEN)
918 return -EINVAL;
919
920 if (addr->can_family != AF_CAN)
921 return -EINVAL;
922
923 ifindex = addr->can_ifindex;
924 } else {
925 ifindex = ro->ifindex;
926 }
927
928 dev = dev_get_by_index(sock_net(sk), ifindex);
929 if (!dev)
930 return -ENXIO;
931
932 skb = sock_alloc_send_skb(sk, size + sizeof(struct can_skb_priv),
933 msg->msg_flags & MSG_DONTWAIT, &err);
934 if (!skb)
935 goto put_dev;
936
937 can_skb_reserve(skb);
938 can_skb_prv(skb)->ifindex = dev->ifindex;
939 can_skb_prv(skb)->skbcnt = 0;
940
941 /* fill the skb before testing for valid CAN frames */
942 err = memcpy_from_msg(skb_put(skb, size), msg, size);
943 if (err < 0)
944 goto free_skb;
945
946 err = -EINVAL;
947
948 /* check for valid CAN (CC/FD/XL) frame content */
949 txmtu = raw_check_txframe(ro, skb, dev->mtu);
950 if (!txmtu)
951 goto free_skb;
952
953 /* only CANXL: clear/forward/set VCID value */
954 if (txmtu == CANXL_MTU)
955 raw_put_canxl_vcid(ro, skb);
956
957 sockcm_init(&sockc, sk);
958 if (msg->msg_controllen) {
959 err = sock_cmsg_send(sk, msg, &sockc);
960 if (unlikely(err))
961 goto free_skb;
962 }
963
964 skb->dev = dev;
965 skb->priority = READ_ONCE(sk->sk_priority);
966 skb->mark = READ_ONCE(sk->sk_mark);
967 skb->tstamp = sockc.transmit_time;
968
969 skb_setup_tx_timestamp(skb, sockc.tsflags);
970
971 err = can_send(skb, ro->loopback);
972
973 dev_put(dev);
974
975 if (err)
976 goto send_failed;
977
978 return size;
979
980free_skb:
981 kfree_skb(skb);
982put_dev:
983 dev_put(dev);
984send_failed:
985 return err;
986}
987
988static int raw_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
989 int flags)
990{
991 struct sock *sk = sock->sk;
992 struct sk_buff *skb;
993 int err = 0;
994
995 if (flags & MSG_ERRQUEUE)
996 return sock_recv_errqueue(sk, msg, size,
997 SOL_CAN_RAW, SCM_CAN_RAW_ERRQUEUE);
998
999 skb = skb_recv_datagram(sk, flags, &err);
1000 if (!skb)
1001 return err;
1002
1003 if (size < skb->len)
1004 msg->msg_flags |= MSG_TRUNC;
1005 else
1006 size = skb->len;
1007
1008 err = memcpy_to_msg(msg, skb->data, size);
1009 if (err < 0) {
1010 skb_free_datagram(sk, skb);
1011 return err;
1012 }
1013
1014 sock_recv_cmsgs(msg, sk, skb);
1015
1016 if (msg->msg_name) {
1017 __sockaddr_check_size(RAW_MIN_NAMELEN);
1018 msg->msg_namelen = RAW_MIN_NAMELEN;
1019 memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
1020 }
1021
1022 /* assign the flags that have been recorded in raw_rcv() */
1023 msg->msg_flags |= *(raw_flags(skb));
1024
1025 skb_free_datagram(sk, skb);
1026
1027 return size;
1028}
1029
1030static int raw_sock_no_ioctlcmd(struct socket *sock, unsigned int cmd,
1031 unsigned long arg)
1032{
1033 /* no ioctls for socket layer -> hand it down to NIC layer */
1034 return -ENOIOCTLCMD;
1035}
1036
1037static const struct proto_ops raw_ops = {
1038 .family = PF_CAN,
1039 .release = raw_release,
1040 .bind = raw_bind,
1041 .connect = sock_no_connect,
1042 .socketpair = sock_no_socketpair,
1043 .accept = sock_no_accept,
1044 .getname = raw_getname,
1045 .poll = datagram_poll,
1046 .ioctl = raw_sock_no_ioctlcmd,
1047 .gettstamp = sock_gettstamp,
1048 .listen = sock_no_listen,
1049 .shutdown = sock_no_shutdown,
1050 .setsockopt = raw_setsockopt,
1051 .getsockopt = raw_getsockopt,
1052 .sendmsg = raw_sendmsg,
1053 .recvmsg = raw_recvmsg,
1054 .mmap = sock_no_mmap,
1055};
1056
1057static struct proto raw_proto __read_mostly = {
1058 .name = "CAN_RAW",
1059 .owner = THIS_MODULE,
1060 .obj_size = sizeof(struct raw_sock),
1061 .init = raw_init,
1062};
1063
1064static const struct can_proto raw_can_proto = {
1065 .type = SOCK_RAW,
1066 .protocol = CAN_RAW,
1067 .ops = &raw_ops,
1068 .prot = &raw_proto,
1069};
1070
1071static struct notifier_block canraw_notifier = {
1072 .notifier_call = raw_notifier
1073};
1074
1075static __init int raw_module_init(void)
1076{
1077 int err;
1078
1079 pr_info("can: raw protocol\n");
1080
1081 err = register_netdevice_notifier(&canraw_notifier);
1082 if (err)
1083 return err;
1084
1085 err = can_proto_register(&raw_can_proto);
1086 if (err < 0) {
1087 pr_err("can: registration of raw protocol failed\n");
1088 goto register_proto_failed;
1089 }
1090
1091 return 0;
1092
1093register_proto_failed:
1094 unregister_netdevice_notifier(&canraw_notifier);
1095 return err;
1096}
1097
1098static __exit void raw_module_exit(void)
1099{
1100 can_proto_unregister(&raw_can_proto);
1101 unregister_netdevice_notifier(&canraw_notifier);
1102}
1103
1104module_init(raw_module_init);
1105module_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);