2 * raw.c - Raw sockets for protocol family CAN
4 * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
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.
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.
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.
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
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>
56 #include <net/net_namespace.h>
58 #define CAN_RAW_VERSION CAN_VERSION
60 MODULE_DESCRIPTION("PF_CAN raw protocol");
61 MODULE_LICENSE("Dual BSD/GPL");
62 MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>");
63 MODULE_ALIAS("can-proto-1");
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.
79 const struct sk_buff
*skb
;
80 unsigned int join_rx_count
;
87 struct notifier_block notifier
;
92 int count
; /* number of active filters */
93 struct can_filter dfilter
; /* default/single filter */
94 struct can_filter
*filter
; /* pointer to filter(s) */
95 can_err_mask_t err_mask
;
96 struct uniqframe __percpu
*uniq
;
100 * Return pointer to store the extra msg flags for raw_recvmsg().
101 * We use the space of one unsigned int beyond the 'struct sockaddr_can'
104 static inline unsigned int *raw_flags(struct sk_buff
*skb
)
106 sock_skb_cb_check_size(sizeof(struct sockaddr_can
) +
107 sizeof(unsigned int));
109 /* return pointer after struct sockaddr_can */
110 return (unsigned int *)(&((struct sockaddr_can
*)skb
->cb
)[1]);
113 static inline struct raw_sock
*raw_sk(const struct sock
*sk
)
115 return (struct raw_sock
*)sk
;
118 static void raw_rcv(struct sk_buff
*oskb
, void *data
)
120 struct sock
*sk
= (struct sock
*)data
;
121 struct raw_sock
*ro
= raw_sk(sk
);
122 struct sockaddr_can
*addr
;
124 unsigned int *pflags
;
126 /* check the received tx sock reference */
127 if (!ro
->recv_own_msgs
&& oskb
->sk
== sk
)
130 /* do not pass non-CAN2.0 frames to a legacy socket */
131 if (!ro
->fd_frames
&& oskb
->len
!= CAN_MTU
)
134 /* eliminate multiple filter matches for the same skb */
135 if (this_cpu_ptr(ro
->uniq
)->skb
== oskb
&&
136 this_cpu_ptr(ro
->uniq
)->skbcnt
== can_skb_prv(oskb
)->skbcnt
) {
137 if (ro
->join_filters
) {
138 this_cpu_inc(ro
->uniq
->join_rx_count
);
139 /* drop frame until all enabled filters matched */
140 if (this_cpu_ptr(ro
->uniq
)->join_rx_count
< ro
->count
)
146 this_cpu_ptr(ro
->uniq
)->skb
= oskb
;
147 this_cpu_ptr(ro
->uniq
)->skbcnt
= can_skb_prv(oskb
)->skbcnt
;
148 this_cpu_ptr(ro
->uniq
)->join_rx_count
= 1;
149 /* drop first frame to check all enabled filters? */
150 if (ro
->join_filters
&& ro
->count
> 1)
154 /* clone the given skb to be able to enqueue it into the rcv queue */
155 skb
= skb_clone(oskb
, GFP_ATOMIC
);
160 * Put the datagram to the queue so that raw_recvmsg() can
161 * get it from there. We need to pass the interface index to
162 * raw_recvmsg(). We pass a whole struct sockaddr_can in skb->cb
163 * containing the interface index.
166 sock_skb_cb_check_size(sizeof(struct sockaddr_can
));
167 addr
= (struct sockaddr_can
*)skb
->cb
;
168 memset(addr
, 0, sizeof(*addr
));
169 addr
->can_family
= AF_CAN
;
170 addr
->can_ifindex
= skb
->dev
->ifindex
;
172 /* add CAN specific message flags for raw_recvmsg() */
173 pflags
= raw_flags(skb
);
176 *pflags
|= MSG_DONTROUTE
;
178 *pflags
|= MSG_CONFIRM
;
180 if (sock_queue_rcv_skb(sk
, skb
) < 0)
184 static int raw_enable_filters(struct net_device
*dev
, struct sock
*sk
,
185 struct can_filter
*filter
, int count
)
190 for (i
= 0; i
< count
; i
++) {
191 err
= can_rx_register(dev
, filter
[i
].can_id
,
195 /* clean up successfully registered filters */
197 can_rx_unregister(dev
, filter
[i
].can_id
,
207 static int raw_enable_errfilter(struct net_device
*dev
, struct sock
*sk
,
208 can_err_mask_t err_mask
)
213 err
= can_rx_register(dev
, 0, err_mask
| CAN_ERR_FLAG
,
219 static void raw_disable_filters(struct net_device
*dev
, struct sock
*sk
,
220 struct can_filter
*filter
, int count
)
224 for (i
= 0; i
< count
; i
++)
225 can_rx_unregister(dev
, filter
[i
].can_id
, filter
[i
].can_mask
,
229 static inline void raw_disable_errfilter(struct net_device
*dev
,
231 can_err_mask_t err_mask
)
235 can_rx_unregister(dev
, 0, err_mask
| CAN_ERR_FLAG
,
239 static inline void raw_disable_allfilters(struct net_device
*dev
,
242 struct raw_sock
*ro
= raw_sk(sk
);
244 raw_disable_filters(dev
, sk
, ro
->filter
, ro
->count
);
245 raw_disable_errfilter(dev
, sk
, ro
->err_mask
);
248 static int raw_enable_allfilters(struct net_device
*dev
, struct sock
*sk
)
250 struct raw_sock
*ro
= raw_sk(sk
);
253 err
= raw_enable_filters(dev
, sk
, ro
->filter
, ro
->count
);
255 err
= raw_enable_errfilter(dev
, sk
, ro
->err_mask
);
257 raw_disable_filters(dev
, sk
, ro
->filter
, ro
->count
);
263 static int raw_notifier(struct notifier_block
*nb
,
264 unsigned long msg
, void *ptr
)
266 struct net_device
*dev
= netdev_notifier_info_to_dev(ptr
);
267 struct raw_sock
*ro
= container_of(nb
, struct raw_sock
, notifier
);
268 struct sock
*sk
= &ro
->sk
;
270 if (!net_eq(dev_net(dev
), &init_net
))
273 if (dev
->type
!= ARPHRD_CAN
)
276 if (ro
->ifindex
!= dev
->ifindex
)
281 case NETDEV_UNREGISTER
:
283 /* remove current filters & unregister */
285 raw_disable_allfilters(dev
, sk
);
296 if (!sock_flag(sk
, SOCK_DEAD
))
297 sk
->sk_error_report(sk
);
301 sk
->sk_err
= ENETDOWN
;
302 if (!sock_flag(sk
, SOCK_DEAD
))
303 sk
->sk_error_report(sk
);
310 static int raw_init(struct sock
*sk
)
312 struct raw_sock
*ro
= raw_sk(sk
);
317 /* set default filter to single entry dfilter */
318 ro
->dfilter
.can_id
= 0;
319 ro
->dfilter
.can_mask
= MASK_ALL
;
320 ro
->filter
= &ro
->dfilter
;
323 /* set default loopback behaviour */
325 ro
->recv_own_msgs
= 0;
327 ro
->join_filters
= 0;
329 /* alloc_percpu provides zero'ed memory */
330 ro
->uniq
= alloc_percpu(struct uniqframe
);
331 if (unlikely(!ro
->uniq
))
335 ro
->notifier
.notifier_call
= raw_notifier
;
337 register_netdevice_notifier(&ro
->notifier
);
342 static int raw_release(struct socket
*sock
)
344 struct sock
*sk
= sock
->sk
;
352 unregister_netdevice_notifier(&ro
->notifier
);
356 /* remove current filters & unregister */
359 struct net_device
*dev
;
361 dev
= dev_get_by_index(&init_net
, ro
->ifindex
);
363 raw_disable_allfilters(dev
, sk
);
367 raw_disable_allfilters(NULL
, sk
);
376 free_percpu(ro
->uniq
);
387 static int raw_bind(struct socket
*sock
, struct sockaddr
*uaddr
, int len
)
389 struct sockaddr_can
*addr
= (struct sockaddr_can
*)uaddr
;
390 struct sock
*sk
= sock
->sk
;
391 struct raw_sock
*ro
= raw_sk(sk
);
394 int notify_enetdown
= 0;
396 if (len
< sizeof(*addr
))
401 if (ro
->bound
&& addr
->can_ifindex
== ro
->ifindex
)
404 if (addr
->can_ifindex
) {
405 struct net_device
*dev
;
407 dev
= dev_get_by_index(&init_net
, addr
->can_ifindex
);
412 if (dev
->type
!= ARPHRD_CAN
) {
417 if (!(dev
->flags
& IFF_UP
))
420 ifindex
= dev
->ifindex
;
422 /* filters set by default/setsockopt */
423 err
= raw_enable_allfilters(dev
, sk
);
428 /* filters set by default/setsockopt */
429 err
= raw_enable_allfilters(NULL
, sk
);
434 /* unregister old filters */
436 struct net_device
*dev
;
438 dev
= dev_get_by_index(&init_net
, ro
->ifindex
);
440 raw_disable_allfilters(dev
, sk
);
444 raw_disable_allfilters(NULL
, sk
);
446 ro
->ifindex
= ifindex
;
453 if (notify_enetdown
) {
454 sk
->sk_err
= ENETDOWN
;
455 if (!sock_flag(sk
, SOCK_DEAD
))
456 sk
->sk_error_report(sk
);
462 static int raw_getname(struct socket
*sock
, struct sockaddr
*uaddr
,
465 struct sockaddr_can
*addr
= (struct sockaddr_can
*)uaddr
;
466 struct sock
*sk
= sock
->sk
;
467 struct raw_sock
*ro
= raw_sk(sk
);
472 memset(addr
, 0, sizeof(*addr
));
473 addr
->can_family
= AF_CAN
;
474 addr
->can_ifindex
= ro
->ifindex
;
476 *len
= sizeof(*addr
);
481 static int raw_setsockopt(struct socket
*sock
, int level
, int optname
,
482 char __user
*optval
, unsigned int optlen
)
484 struct sock
*sk
= sock
->sk
;
485 struct raw_sock
*ro
= raw_sk(sk
);
486 struct can_filter
*filter
= NULL
; /* dyn. alloc'ed filters */
487 struct can_filter sfilter
; /* single filter */
488 struct net_device
*dev
= NULL
;
489 can_err_mask_t err_mask
= 0;
493 if (level
!= SOL_CAN_RAW
)
499 if (optlen
% sizeof(struct can_filter
) != 0)
502 count
= optlen
/ sizeof(struct can_filter
);
505 /* filter does not fit into dfilter => alloc space */
506 filter
= memdup_user(optval
, optlen
);
508 return PTR_ERR(filter
);
509 } else if (count
== 1) {
510 if (copy_from_user(&sfilter
, optval
, sizeof(sfilter
)))
516 if (ro
->bound
&& ro
->ifindex
)
517 dev
= dev_get_by_index(&init_net
, ro
->ifindex
);
520 /* (try to) register the new filters */
522 err
= raw_enable_filters(dev
, sk
, &sfilter
, 1);
524 err
= raw_enable_filters(dev
, sk
, filter
,
532 /* remove old filter registrations */
533 raw_disable_filters(dev
, sk
, ro
->filter
, ro
->count
);
536 /* remove old filter space */
540 /* link new filters to the socket */
542 /* copy filter data for single filter */
543 ro
->dfilter
= sfilter
;
544 filter
= &ro
->dfilter
;
557 case CAN_RAW_ERR_FILTER
:
558 if (optlen
!= sizeof(err_mask
))
561 if (copy_from_user(&err_mask
, optval
, optlen
))
564 err_mask
&= CAN_ERR_MASK
;
568 if (ro
->bound
&& ro
->ifindex
)
569 dev
= dev_get_by_index(&init_net
, ro
->ifindex
);
571 /* remove current error mask */
573 /* (try to) register the new err_mask */
574 err
= raw_enable_errfilter(dev
, sk
, err_mask
);
579 /* remove old err_mask registration */
580 raw_disable_errfilter(dev
, sk
, ro
->err_mask
);
583 /* link new err_mask to the socket */
584 ro
->err_mask
= err_mask
;
594 case CAN_RAW_LOOPBACK
:
595 if (optlen
!= sizeof(ro
->loopback
))
598 if (copy_from_user(&ro
->loopback
, optval
, optlen
))
603 case CAN_RAW_RECV_OWN_MSGS
:
604 if (optlen
!= sizeof(ro
->recv_own_msgs
))
607 if (copy_from_user(&ro
->recv_own_msgs
, optval
, optlen
))
612 case CAN_RAW_FD_FRAMES
:
613 if (optlen
!= sizeof(ro
->fd_frames
))
616 if (copy_from_user(&ro
->fd_frames
, optval
, optlen
))
621 case CAN_RAW_JOIN_FILTERS
:
622 if (optlen
!= sizeof(ro
->join_filters
))
625 if (copy_from_user(&ro
->join_filters
, optval
, optlen
))
636 static int raw_getsockopt(struct socket
*sock
, int level
, int optname
,
637 char __user
*optval
, int __user
*optlen
)
639 struct sock
*sk
= sock
->sk
;
640 struct raw_sock
*ro
= raw_sk(sk
);
645 if (level
!= SOL_CAN_RAW
)
647 if (get_user(len
, optlen
))
657 int fsize
= ro
->count
* sizeof(struct can_filter
);
660 if (copy_to_user(optval
, ro
->filter
, len
))
667 err
= put_user(len
, optlen
);
670 case CAN_RAW_ERR_FILTER
:
671 if (len
> sizeof(can_err_mask_t
))
672 len
= sizeof(can_err_mask_t
);
676 case CAN_RAW_LOOPBACK
:
677 if (len
> sizeof(int))
682 case CAN_RAW_RECV_OWN_MSGS
:
683 if (len
> sizeof(int))
685 val
= &ro
->recv_own_msgs
;
688 case CAN_RAW_FD_FRAMES
:
689 if (len
> sizeof(int))
691 val
= &ro
->fd_frames
;
694 case CAN_RAW_JOIN_FILTERS
:
695 if (len
> sizeof(int))
697 val
= &ro
->join_filters
;
704 if (put_user(len
, optlen
))
706 if (copy_to_user(optval
, val
, len
))
711 static int raw_sendmsg(struct socket
*sock
, struct msghdr
*msg
, size_t size
)
713 struct sock
*sk
= sock
->sk
;
714 struct raw_sock
*ro
= raw_sk(sk
);
716 struct net_device
*dev
;
721 DECLARE_SOCKADDR(struct sockaddr_can
*, addr
, msg
->msg_name
);
723 if (msg
->msg_namelen
< sizeof(*addr
))
726 if (addr
->can_family
!= AF_CAN
)
729 ifindex
= addr
->can_ifindex
;
731 ifindex
= ro
->ifindex
;
734 if (unlikely(size
!= CANFD_MTU
&& size
!= CAN_MTU
))
737 if (unlikely(size
!= CAN_MTU
))
741 dev
= dev_get_by_index(&init_net
, ifindex
);
745 skb
= sock_alloc_send_skb(sk
, size
+ sizeof(struct can_skb_priv
),
746 msg
->msg_flags
& MSG_DONTWAIT
, &err
);
750 can_skb_reserve(skb
);
751 can_skb_prv(skb
)->ifindex
= dev
->ifindex
;
752 can_skb_prv(skb
)->skbcnt
= 0;
754 err
= memcpy_from_msg(skb_put(skb
, size
), msg
, size
);
758 sock_tx_timestamp(sk
, sk
->sk_tsflags
, &skb_shinfo(skb
)->tx_flags
);
762 skb
->priority
= sk
->sk_priority
;
764 err
= can_send(skb
, ro
->loopback
);
781 static int raw_recvmsg(struct socket
*sock
, struct msghdr
*msg
, size_t size
,
784 struct sock
*sk
= sock
->sk
;
789 noblock
= flags
& MSG_DONTWAIT
;
790 flags
&= ~MSG_DONTWAIT
;
792 skb
= skb_recv_datagram(sk
, flags
, noblock
, &err
);
797 msg
->msg_flags
|= MSG_TRUNC
;
801 err
= memcpy_to_msg(msg
, skb
->data
, size
);
803 skb_free_datagram(sk
, skb
);
807 sock_recv_ts_and_drops(msg
, sk
, skb
);
810 __sockaddr_check_size(sizeof(struct sockaddr_can
));
811 msg
->msg_namelen
= sizeof(struct sockaddr_can
);
812 memcpy(msg
->msg_name
, skb
->cb
, msg
->msg_namelen
);
815 /* assign the flags that have been recorded in raw_rcv() */
816 msg
->msg_flags
|= *(raw_flags(skb
));
818 skb_free_datagram(sk
, skb
);
823 static const struct proto_ops raw_ops
= {
825 .release
= raw_release
,
827 .connect
= sock_no_connect
,
828 .socketpair
= sock_no_socketpair
,
829 .accept
= sock_no_accept
,
830 .getname
= raw_getname
,
831 .poll
= datagram_poll
,
832 .ioctl
= can_ioctl
, /* use can_ioctl() from af_can.c */
833 .listen
= sock_no_listen
,
834 .shutdown
= sock_no_shutdown
,
835 .setsockopt
= raw_setsockopt
,
836 .getsockopt
= raw_getsockopt
,
837 .sendmsg
= raw_sendmsg
,
838 .recvmsg
= raw_recvmsg
,
839 .mmap
= sock_no_mmap
,
840 .sendpage
= sock_no_sendpage
,
843 static struct proto raw_proto __read_mostly
= {
845 .owner
= THIS_MODULE
,
846 .obj_size
= sizeof(struct raw_sock
),
850 static const struct can_proto raw_can_proto
= {
857 static __init
int raw_module_init(void)
861 pr_info("can: raw protocol (rev " CAN_RAW_VERSION
")\n");
863 err
= can_proto_register(&raw_can_proto
);
865 printk(KERN_ERR
"can: registration of raw protocol failed\n");
870 static __exit
void raw_module_exit(void)
872 can_proto_unregister(&raw_can_proto
);
875 module_init(raw_module_init
);
876 module_exit(raw_module_exit
);