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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/raw.h>
54#include <net/sock.h>
55#include <net/net_namespace.h>
56
57#define CAN_RAW_VERSION CAN_VERSION
58static __initconst const char banner[] =
59 KERN_INFO "can: raw protocol (rev " CAN_RAW_VERSION ")\n";
60
61MODULE_DESCRIPTION("PF_CAN raw protocol");
62MODULE_LICENSE("Dual BSD/GPL");
63MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>");
64MODULE_ALIAS("can-proto-1");
65
66#define MASK_ALL 0
67
68
69
70
71
72
73
74
75
76
77
78struct raw_sock {
79 struct sock sk;
80 int bound;
81 int ifindex;
82 struct notifier_block notifier;
83 int loopback;
84 int recv_own_msgs;
85 int fd_frames;
86 int count;
87 struct can_filter dfilter;
88 struct can_filter *filter;
89 can_err_mask_t err_mask;
90};
91
92
93
94
95
96
97static inline unsigned int *raw_flags(struct sk_buff *skb)
98{
99 BUILD_BUG_ON(sizeof(skb->cb) <= (sizeof(struct sockaddr_can) +
100 sizeof(unsigned int)));
101
102
103 return (unsigned int *)(&((struct sockaddr_can *)skb->cb)[1]);
104}
105
106static inline struct raw_sock *raw_sk(const struct sock *sk)
107{
108 return (struct raw_sock *)sk;
109}
110
111static void raw_rcv(struct sk_buff *oskb, void *data)
112{
113 struct sock *sk = (struct sock *)data;
114 struct raw_sock *ro = raw_sk(sk);
115 struct sockaddr_can *addr;
116 struct sk_buff *skb;
117 unsigned int *pflags;
118
119
120 if (!ro->recv_own_msgs && oskb->sk == sk)
121 return;
122
123
124 if (!ro->fd_frames) {
125 struct canfd_frame *cfd = (struct canfd_frame *)oskb->data;
126
127 if (unlikely(cfd->len > CAN_MAX_DLEN))
128 return;
129 }
130
131
132 skb = skb_clone(oskb, GFP_ATOMIC);
133 if (!skb)
134 return;
135
136
137
138
139
140
141
142
143 BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct sockaddr_can));
144 addr = (struct sockaddr_can *)skb->cb;
145 memset(addr, 0, sizeof(*addr));
146 addr->can_family = AF_CAN;
147 addr->can_ifindex = skb->dev->ifindex;
148
149
150 pflags = raw_flags(skb);
151 *pflags = 0;
152 if (oskb->sk)
153 *pflags |= MSG_DONTROUTE;
154 if (oskb->sk == sk)
155 *pflags |= MSG_CONFIRM;
156
157 if (sock_queue_rcv_skb(sk, skb) < 0)
158 kfree_skb(skb);
159}
160
161static int raw_enable_filters(struct net_device *dev, struct sock *sk,
162 struct can_filter *filter, int count)
163{
164 int err = 0;
165 int i;
166
167 for (i = 0; i < count; i++) {
168 err = can_rx_register(dev, filter[i].can_id,
169 filter[i].can_mask,
170 raw_rcv, sk, "raw");
171 if (err) {
172
173 while (--i >= 0)
174 can_rx_unregister(dev, filter[i].can_id,
175 filter[i].can_mask,
176 raw_rcv, sk);
177 break;
178 }
179 }
180
181 return err;
182}
183
184static int raw_enable_errfilter(struct net_device *dev, struct sock *sk,
185 can_err_mask_t err_mask)
186{
187 int err = 0;
188
189 if (err_mask)
190 err = can_rx_register(dev, 0, err_mask | CAN_ERR_FLAG,
191 raw_rcv, sk, "raw");
192
193 return err;
194}
195
196static void raw_disable_filters(struct net_device *dev, struct sock *sk,
197 struct can_filter *filter, int count)
198{
199 int i;
200
201 for (i = 0; i < count; i++)
202 can_rx_unregister(dev, filter[i].can_id, filter[i].can_mask,
203 raw_rcv, sk);
204}
205
206static inline void raw_disable_errfilter(struct net_device *dev,
207 struct sock *sk,
208 can_err_mask_t err_mask)
209
210{
211 if (err_mask)
212 can_rx_unregister(dev, 0, err_mask | CAN_ERR_FLAG,
213 raw_rcv, sk);
214}
215
216static inline void raw_disable_allfilters(struct net_device *dev,
217 struct sock *sk)
218{
219 struct raw_sock *ro = raw_sk(sk);
220
221 raw_disable_filters(dev, sk, ro->filter, ro->count);
222 raw_disable_errfilter(dev, sk, ro->err_mask);
223}
224
225static int raw_enable_allfilters(struct net_device *dev, struct sock *sk)
226{
227 struct raw_sock *ro = raw_sk(sk);
228 int err;
229
230 err = raw_enable_filters(dev, sk, ro->filter, ro->count);
231 if (!err) {
232 err = raw_enable_errfilter(dev, sk, ro->err_mask);
233 if (err)
234 raw_disable_filters(dev, sk, ro->filter, ro->count);
235 }
236
237 return err;
238}
239
240static int raw_notifier(struct notifier_block *nb,
241 unsigned long msg, void *data)
242{
243 struct net_device *dev = (struct net_device *)data;
244 struct raw_sock *ro = container_of(nb, struct raw_sock, notifier);
245 struct sock *sk = &ro->sk;
246
247 if (!net_eq(dev_net(dev), &init_net))
248 return NOTIFY_DONE;
249
250 if (dev->type != ARPHRD_CAN)
251 return NOTIFY_DONE;
252
253 if (ro->ifindex != dev->ifindex)
254 return NOTIFY_DONE;
255
256 switch (msg) {
257
258 case NETDEV_UNREGISTER:
259 lock_sock(sk);
260
261 if (ro->bound)
262 raw_disable_allfilters(dev, sk);
263
264 if (ro->count > 1)
265 kfree(ro->filter);
266
267 ro->ifindex = 0;
268 ro->bound = 0;
269 ro->count = 0;
270 release_sock(sk);
271
272 sk->sk_err = ENODEV;
273 if (!sock_flag(sk, SOCK_DEAD))
274 sk->sk_error_report(sk);
275 break;
276
277 case NETDEV_DOWN:
278 sk->sk_err = ENETDOWN;
279 if (!sock_flag(sk, SOCK_DEAD))
280 sk->sk_error_report(sk);
281 break;
282 }
283
284 return NOTIFY_DONE;
285}
286
287static int raw_init(struct sock *sk)
288{
289 struct raw_sock *ro = raw_sk(sk);
290
291 ro->bound = 0;
292 ro->ifindex = 0;
293
294
295 ro->dfilter.can_id = 0;
296 ro->dfilter.can_mask = MASK_ALL;
297 ro->filter = &ro->dfilter;
298 ro->count = 1;
299
300
301 ro->loopback = 1;
302 ro->recv_own_msgs = 0;
303 ro->fd_frames = 0;
304
305
306 ro->notifier.notifier_call = raw_notifier;
307
308 register_netdevice_notifier(&ro->notifier);
309
310 return 0;
311}
312
313static int raw_release(struct socket *sock)
314{
315 struct sock *sk = sock->sk;
316 struct raw_sock *ro;
317
318 if (!sk)
319 return 0;
320
321 ro = raw_sk(sk);
322
323 unregister_netdevice_notifier(&ro->notifier);
324
325 lock_sock(sk);
326
327
328 if (ro->bound) {
329 if (ro->ifindex) {
330 struct net_device *dev;
331
332 dev = dev_get_by_index(&init_net, ro->ifindex);
333 if (dev) {
334 raw_disable_allfilters(dev, sk);
335 dev_put(dev);
336 }
337 } else
338 raw_disable_allfilters(NULL, sk);
339 }
340
341 if (ro->count > 1)
342 kfree(ro->filter);
343
344 ro->ifindex = 0;
345 ro->bound = 0;
346 ro->count = 0;
347
348 sock_orphan(sk);
349 sock->sk = NULL;
350
351 release_sock(sk);
352 sock_put(sk);
353
354 return 0;
355}
356
357static int raw_bind(struct socket *sock, struct sockaddr *uaddr, int len)
358{
359 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
360 struct sock *sk = sock->sk;
361 struct raw_sock *ro = raw_sk(sk);
362 int ifindex;
363 int err = 0;
364 int notify_enetdown = 0;
365
366 if (len < sizeof(*addr))
367 return -EINVAL;
368
369 lock_sock(sk);
370
371 if (ro->bound && addr->can_ifindex == ro->ifindex)
372 goto out;
373
374 if (addr->can_ifindex) {
375 struct net_device *dev;
376
377 dev = dev_get_by_index(&init_net, addr->can_ifindex);
378 if (!dev) {
379 err = -ENODEV;
380 goto out;
381 }
382 if (dev->type != ARPHRD_CAN) {
383 dev_put(dev);
384 err = -ENODEV;
385 goto out;
386 }
387 if (!(dev->flags & IFF_UP))
388 notify_enetdown = 1;
389
390 ifindex = dev->ifindex;
391
392
393 err = raw_enable_allfilters(dev, sk);
394 dev_put(dev);
395 } else {
396 ifindex = 0;
397
398
399 err = raw_enable_allfilters(NULL, sk);
400 }
401
402 if (!err) {
403 if (ro->bound) {
404
405 if (ro->ifindex) {
406 struct net_device *dev;
407
408 dev = dev_get_by_index(&init_net, ro->ifindex);
409 if (dev) {
410 raw_disable_allfilters(dev, sk);
411 dev_put(dev);
412 }
413 } else
414 raw_disable_allfilters(NULL, sk);
415 }
416 ro->ifindex = ifindex;
417 ro->bound = 1;
418 }
419
420 out:
421 release_sock(sk);
422
423 if (notify_enetdown) {
424 sk->sk_err = ENETDOWN;
425 if (!sock_flag(sk, SOCK_DEAD))
426 sk->sk_error_report(sk);
427 }
428
429 return err;
430}
431
432static int raw_getname(struct socket *sock, struct sockaddr *uaddr,
433 int *len, int peer)
434{
435 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
436 struct sock *sk = sock->sk;
437 struct raw_sock *ro = raw_sk(sk);
438
439 if (peer)
440 return -EOPNOTSUPP;
441
442 memset(addr, 0, sizeof(*addr));
443 addr->can_family = AF_CAN;
444 addr->can_ifindex = ro->ifindex;
445
446 *len = sizeof(*addr);
447
448 return 0;
449}
450
451static int raw_setsockopt(struct socket *sock, int level, int optname,
452 char __user *optval, unsigned int optlen)
453{
454 struct sock *sk = sock->sk;
455 struct raw_sock *ro = raw_sk(sk);
456 struct can_filter *filter = NULL;
457 struct can_filter sfilter;
458 struct net_device *dev = NULL;
459 can_err_mask_t err_mask = 0;
460 int count = 0;
461 int err = 0;
462
463 if (level != SOL_CAN_RAW)
464 return -EINVAL;
465
466 switch (optname) {
467
468 case CAN_RAW_FILTER:
469 if (optlen % sizeof(struct can_filter) != 0)
470 return -EINVAL;
471
472 count = optlen / sizeof(struct can_filter);
473
474 if (count > 1) {
475
476 filter = memdup_user(optval, optlen);
477 if (IS_ERR(filter))
478 return PTR_ERR(filter);
479 } else if (count == 1) {
480 if (copy_from_user(&sfilter, optval, sizeof(sfilter)))
481 return -EFAULT;
482 }
483
484 lock_sock(sk);
485
486 if (ro->bound && ro->ifindex)
487 dev = dev_get_by_index(&init_net, ro->ifindex);
488
489 if (ro->bound) {
490
491 if (count == 1)
492 err = raw_enable_filters(dev, sk, &sfilter, 1);
493 else
494 err = raw_enable_filters(dev, sk, filter,
495 count);
496 if (err) {
497 if (count > 1)
498 kfree(filter);
499 goto out_fil;
500 }
501
502
503 raw_disable_filters(dev, sk, ro->filter, ro->count);
504 }
505
506
507 if (ro->count > 1)
508 kfree(ro->filter);
509
510
511 if (count == 1) {
512
513 ro->dfilter = sfilter;
514 filter = &ro->dfilter;
515 }
516 ro->filter = filter;
517 ro->count = count;
518
519 out_fil:
520 if (dev)
521 dev_put(dev);
522
523 release_sock(sk);
524
525 break;
526
527 case CAN_RAW_ERR_FILTER:
528 if (optlen != sizeof(err_mask))
529 return -EINVAL;
530
531 if (copy_from_user(&err_mask, optval, optlen))
532 return -EFAULT;
533
534 err_mask &= CAN_ERR_MASK;
535
536 lock_sock(sk);
537
538 if (ro->bound && ro->ifindex)
539 dev = dev_get_by_index(&init_net, ro->ifindex);
540
541
542 if (ro->bound) {
543
544 err = raw_enable_errfilter(dev, sk, err_mask);
545
546 if (err)
547 goto out_err;
548
549
550 raw_disable_errfilter(dev, sk, ro->err_mask);
551 }
552
553
554 ro->err_mask = err_mask;
555
556 out_err:
557 if (dev)
558 dev_put(dev);
559
560 release_sock(sk);
561
562 break;
563
564 case CAN_RAW_LOOPBACK:
565 if (optlen != sizeof(ro->loopback))
566 return -EINVAL;
567
568 if (copy_from_user(&ro->loopback, optval, optlen))
569 return -EFAULT;
570
571 break;
572
573 case CAN_RAW_RECV_OWN_MSGS:
574 if (optlen != sizeof(ro->recv_own_msgs))
575 return -EINVAL;
576
577 if (copy_from_user(&ro->recv_own_msgs, optval, optlen))
578 return -EFAULT;
579
580 break;
581
582 case CAN_RAW_FD_FRAMES:
583 if (optlen != sizeof(ro->fd_frames))
584 return -EINVAL;
585
586 if (copy_from_user(&ro->fd_frames, optval, optlen))
587 return -EFAULT;
588
589 break;
590
591 default:
592 return -ENOPROTOOPT;
593 }
594 return err;
595}
596
597static int raw_getsockopt(struct socket *sock, int level, int optname,
598 char __user *optval, int __user *optlen)
599{
600 struct sock *sk = sock->sk;
601 struct raw_sock *ro = raw_sk(sk);
602 int len;
603 void *val;
604 int err = 0;
605
606 if (level != SOL_CAN_RAW)
607 return -EINVAL;
608 if (get_user(len, optlen))
609 return -EFAULT;
610 if (len < 0)
611 return -EINVAL;
612
613 switch (optname) {
614
615 case CAN_RAW_FILTER:
616 lock_sock(sk);
617 if (ro->count > 0) {
618 int fsize = ro->count * sizeof(struct can_filter);
619 if (len > fsize)
620 len = fsize;
621 if (copy_to_user(optval, ro->filter, len))
622 err = -EFAULT;
623 } else
624 len = 0;
625 release_sock(sk);
626
627 if (!err)
628 err = put_user(len, optlen);
629 return err;
630
631 case CAN_RAW_ERR_FILTER:
632 if (len > sizeof(can_err_mask_t))
633 len = sizeof(can_err_mask_t);
634 val = &ro->err_mask;
635 break;
636
637 case CAN_RAW_LOOPBACK:
638 if (len > sizeof(int))
639 len = sizeof(int);
640 val = &ro->loopback;
641 break;
642
643 case CAN_RAW_RECV_OWN_MSGS:
644 if (len > sizeof(int))
645 len = sizeof(int);
646 val = &ro->recv_own_msgs;
647 break;
648
649 case CAN_RAW_FD_FRAMES:
650 if (len > sizeof(int))
651 len = sizeof(int);
652 val = &ro->fd_frames;
653 break;
654
655 default:
656 return -ENOPROTOOPT;
657 }
658
659 if (put_user(len, optlen))
660 return -EFAULT;
661 if (copy_to_user(optval, val, len))
662 return -EFAULT;
663 return 0;
664}
665
666static int raw_sendmsg(struct kiocb *iocb, struct socket *sock,
667 struct msghdr *msg, size_t size)
668{
669 struct sock *sk = sock->sk;
670 struct raw_sock *ro = raw_sk(sk);
671 struct sk_buff *skb;
672 struct net_device *dev;
673 int ifindex;
674 int err;
675
676 if (msg->msg_name) {
677 struct sockaddr_can *addr =
678 (struct sockaddr_can *)msg->msg_name;
679
680 if (msg->msg_namelen < sizeof(*addr))
681 return -EINVAL;
682
683 if (addr->can_family != AF_CAN)
684 return -EINVAL;
685
686 ifindex = addr->can_ifindex;
687 } else
688 ifindex = ro->ifindex;
689
690 if (ro->fd_frames) {
691 if (unlikely(size != CANFD_MTU && size != CAN_MTU))
692 return -EINVAL;
693 } else {
694 if (unlikely(size != CAN_MTU))
695 return -EINVAL;
696 }
697
698 dev = dev_get_by_index(&init_net, ifindex);
699 if (!dev)
700 return -ENXIO;
701
702 skb = sock_alloc_send_skb(sk, size, msg->msg_flags & MSG_DONTWAIT,
703 &err);
704 if (!skb)
705 goto put_dev;
706
707 err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
708 if (err < 0)
709 goto free_skb;
710 err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
711 if (err < 0)
712 goto free_skb;
713
714 skb->dev = dev;
715 skb->sk = sk;
716
717 err = can_send(skb, ro->loopback);
718
719 dev_put(dev);
720
721 if (err)
722 goto send_failed;
723
724 return size;
725
726free_skb:
727 kfree_skb(skb);
728put_dev:
729 dev_put(dev);
730send_failed:
731 return err;
732}
733
734static int raw_recvmsg(struct kiocb *iocb, struct socket *sock,
735 struct msghdr *msg, size_t size, int flags)
736{
737 struct sock *sk = sock->sk;
738 struct raw_sock *ro = raw_sk(sk);
739 struct sk_buff *skb;
740 int rxmtu;
741 int err = 0;
742 int noblock;
743
744 noblock = flags & MSG_DONTWAIT;
745 flags &= ~MSG_DONTWAIT;
746
747 skb = skb_recv_datagram(sk, flags, noblock, &err);
748 if (!skb)
749 return err;
750
751
752
753
754
755
756 if (!ro->fd_frames)
757 rxmtu = CAN_MTU;
758 else
759 rxmtu = skb->len;
760
761 if (size < rxmtu)
762 msg->msg_flags |= MSG_TRUNC;
763 else
764 size = rxmtu;
765
766 err = memcpy_toiovec(msg->msg_iov, skb->data, size);
767 if (err < 0) {
768 skb_free_datagram(sk, skb);
769 return err;
770 }
771
772 sock_recv_ts_and_drops(msg, sk, skb);
773
774 if (msg->msg_name) {
775 msg->msg_namelen = sizeof(struct sockaddr_can);
776 memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
777 }
778
779
780 msg->msg_flags |= *(raw_flags(skb));
781
782 skb_free_datagram(sk, skb);
783
784 return size;
785}
786
787static const struct proto_ops raw_ops = {
788 .family = PF_CAN,
789 .release = raw_release,
790 .bind = raw_bind,
791 .connect = sock_no_connect,
792 .socketpair = sock_no_socketpair,
793 .accept = sock_no_accept,
794 .getname = raw_getname,
795 .poll = datagram_poll,
796 .ioctl = can_ioctl,
797 .listen = sock_no_listen,
798 .shutdown = sock_no_shutdown,
799 .setsockopt = raw_setsockopt,
800 .getsockopt = raw_getsockopt,
801 .sendmsg = raw_sendmsg,
802 .recvmsg = raw_recvmsg,
803 .mmap = sock_no_mmap,
804 .sendpage = sock_no_sendpage,
805};
806
807static struct proto raw_proto __read_mostly = {
808 .name = "CAN_RAW",
809 .owner = THIS_MODULE,
810 .obj_size = sizeof(struct raw_sock),
811 .init = raw_init,
812};
813
814static const struct can_proto raw_can_proto = {
815 .type = SOCK_RAW,
816 .protocol = CAN_RAW,
817 .ops = &raw_ops,
818 .prot = &raw_proto,
819};
820
821static __init int raw_module_init(void)
822{
823 int err;
824
825 printk(banner);
826
827 err = can_proto_register(&raw_can_proto);
828 if (err < 0)
829 printk(KERN_ERR "can: registration of raw protocol failed\n");
830
831 return err;
832}
833
834static __exit void raw_module_exit(void)
835{
836 can_proto_unregister(&raw_can_proto);
837}
838
839module_init(raw_module_init);
840module_exit(raw_module_exit);
841