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
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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
59 static __initconst const char banner[] =
60 KERN_INFO "can: raw protocol (rev " CAN_RAW_VERSION ")\n";
62 MODULE_DESCRIPTION("PF_CAN raw protocol");
63 MODULE_LICENSE("Dual BSD/GPL");
65 MODULE_ALIAS("can-proto-1");
70 * A raw socket has a list of can_filters attached to it, each receiving
71 * the CAN frames matching that filter. If the filter list is empty,
72 * no CAN frames will be received by the socket. The default after
73 * opening the socket, is to have one filter which receives all frames.
74 * The filter list is allocated dynamically with the exception of the
75 * list containing only one item. This common case is optimized by
76 * storing the single filter in dfilter, to avoid using dynamic memory.
83 struct notifier_block notifier;
87 int count; /* number of active filters */
88 struct can_filter dfilter; /* default/single filter */
89 struct can_filter *filter; /* pointer to filter(s) */
90 can_err_mask_t err_mask;
94 * Return pointer to store the extra msg flags for raw_recvmsg().
95 * We use the space of one unsigned int beyond the 'struct sockaddr_can'
98 static inline unsigned int *raw_flags(struct sk_buff *skb)
100 BUILD_BUG_ON(sizeof(skb->cb) <= (sizeof(struct sockaddr_can) +
101 sizeof(unsigned int)));
103 /* return pointer after struct sockaddr_can */
104 return (unsigned int *)(&((struct sockaddr_can *)skb->cb)[1]);
107 static inline struct raw_sock *raw_sk(const struct sock *sk)
109 return (struct raw_sock *)sk;
112 static void raw_rcv(struct sk_buff *oskb, void *data)
114 struct sock *sk = (struct sock *)data;
115 struct raw_sock *ro = raw_sk(sk);
116 struct sockaddr_can *addr;
118 unsigned int *pflags;
120 /* check the received tx sock reference */
121 if (!ro->recv_own_msgs && oskb->sk == sk)
124 /* do not pass non-CAN2.0 frames to a legacy socket */
125 if (!ro->fd_frames && oskb->len != CAN_MTU)
128 /* clone the given skb to be able to enqueue it into the rcv queue */
129 skb = skb_clone(oskb, GFP_ATOMIC);
134 * Put the datagram to the queue so that raw_recvmsg() can
135 * get it from there. We need to pass the interface index to
136 * raw_recvmsg(). We pass a whole struct sockaddr_can in skb->cb
137 * containing the interface index.
140 BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct sockaddr_can));
141 addr = (struct sockaddr_can *)skb->cb;
142 memset(addr, 0, sizeof(*addr));
143 addr->can_family = AF_CAN;
144 addr->can_ifindex = skb->dev->ifindex;
146 /* add CAN specific message flags for raw_recvmsg() */
147 pflags = raw_flags(skb);
150 *pflags |= MSG_DONTROUTE;
152 *pflags |= MSG_CONFIRM;
154 if (sock_queue_rcv_skb(sk, skb) < 0)
158 static int raw_enable_filters(struct net_device *dev, struct sock *sk,
159 struct can_filter *filter, int count)
164 for (i = 0; i < count; i++) {
165 err = can_rx_register(dev, filter[i].can_id,
169 /* clean up successfully registered filters */
171 can_rx_unregister(dev, filter[i].can_id,
181 static int raw_enable_errfilter(struct net_device *dev, struct sock *sk,
182 can_err_mask_t err_mask)
187 err = can_rx_register(dev, 0, err_mask | CAN_ERR_FLAG,
193 static void raw_disable_filters(struct net_device *dev, struct sock *sk,
194 struct can_filter *filter, int count)
198 for (i = 0; i < count; i++)
199 can_rx_unregister(dev, filter[i].can_id, filter[i].can_mask,
203 static inline void raw_disable_errfilter(struct net_device *dev,
205 can_err_mask_t err_mask)
209 can_rx_unregister(dev, 0, err_mask | CAN_ERR_FLAG,
213 static inline void raw_disable_allfilters(struct net_device *dev,
216 struct raw_sock *ro = raw_sk(sk);
218 raw_disable_filters(dev, sk, ro->filter, ro->count);
219 raw_disable_errfilter(dev, sk, ro->err_mask);
222 static int raw_enable_allfilters(struct net_device *dev, struct sock *sk)
224 struct raw_sock *ro = raw_sk(sk);
227 err = raw_enable_filters(dev, sk, ro->filter, ro->count);
229 err = raw_enable_errfilter(dev, sk, ro->err_mask);
231 raw_disable_filters(dev, sk, ro->filter, ro->count);
237 static int raw_notifier(struct notifier_block *nb,
238 unsigned long msg, void *ptr)
240 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
241 struct raw_sock *ro = container_of(nb, struct raw_sock, notifier);
242 struct sock *sk = &ro->sk;
244 if (!net_eq(dev_net(dev), &init_net))
247 if (dev->type != ARPHRD_CAN)
250 if (ro->ifindex != dev->ifindex)
255 case NETDEV_UNREGISTER:
257 /* remove current filters & unregister */
259 raw_disable_allfilters(dev, sk);
270 if (!sock_flag(sk, SOCK_DEAD))
271 sk->sk_error_report(sk);
275 sk->sk_err = ENETDOWN;
276 if (!sock_flag(sk, SOCK_DEAD))
277 sk->sk_error_report(sk);
284 static int raw_init(struct sock *sk)
286 struct raw_sock *ro = raw_sk(sk);
291 /* set default filter to single entry dfilter */
292 ro->dfilter.can_id = 0;
293 ro->dfilter.can_mask = MASK_ALL;
294 ro->filter = &ro->dfilter;
297 /* set default loopback behaviour */
299 ro->recv_own_msgs = 0;
303 ro->notifier.notifier_call = raw_notifier;
305 register_netdevice_notifier(&ro->notifier);
310 static int raw_release(struct socket *sock)
312 struct sock *sk = sock->sk;
320 unregister_netdevice_notifier(&ro->notifier);
324 /* remove current filters & unregister */
327 struct net_device *dev;
329 dev = dev_get_by_index(&init_net, ro->ifindex);
331 raw_disable_allfilters(dev, sk);
335 raw_disable_allfilters(NULL, sk);
354 static int raw_bind(struct socket *sock, struct sockaddr *uaddr, int len)
356 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
357 struct sock *sk = sock->sk;
358 struct raw_sock *ro = raw_sk(sk);
361 int notify_enetdown = 0;
363 if (len < sizeof(*addr))
368 if (ro->bound && addr->can_ifindex == ro->ifindex)
371 if (addr->can_ifindex) {
372 struct net_device *dev;
374 dev = dev_get_by_index(&init_net, addr->can_ifindex);
379 if (dev->type != ARPHRD_CAN) {
384 if (!(dev->flags & IFF_UP))
387 ifindex = dev->ifindex;
389 /* filters set by default/setsockopt */
390 err = raw_enable_allfilters(dev, sk);
395 /* filters set by default/setsockopt */
396 err = raw_enable_allfilters(NULL, sk);
401 /* unregister old filters */
403 struct net_device *dev;
405 dev = dev_get_by_index(&init_net, ro->ifindex);
407 raw_disable_allfilters(dev, sk);
411 raw_disable_allfilters(NULL, sk);
413 ro->ifindex = ifindex;
420 if (notify_enetdown) {
421 sk->sk_err = ENETDOWN;
422 if (!sock_flag(sk, SOCK_DEAD))
423 sk->sk_error_report(sk);
429 static int raw_getname(struct socket *sock, struct sockaddr *uaddr,
432 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
433 struct sock *sk = sock->sk;
434 struct raw_sock *ro = raw_sk(sk);
439 memset(addr, 0, sizeof(*addr));
440 addr->can_family = AF_CAN;
441 addr->can_ifindex = ro->ifindex;
443 *len = sizeof(*addr);
448 static int raw_setsockopt(struct socket *sock, int level, int optname,
449 char __user *optval, unsigned int optlen)
451 struct sock *sk = sock->sk;
452 struct raw_sock *ro = raw_sk(sk);
453 struct can_filter *filter = NULL; /* dyn. alloc'ed filters */
454 struct can_filter sfilter; /* single filter */
455 struct net_device *dev = NULL;
456 can_err_mask_t err_mask = 0;
460 if (level != SOL_CAN_RAW)
466 if (optlen % sizeof(struct can_filter) != 0)
469 count = optlen / sizeof(struct can_filter);
472 /* filter does not fit into dfilter => alloc space */
473 filter = memdup_user(optval, optlen);
475 return PTR_ERR(filter);
476 } else if (count == 1) {
477 if (copy_from_user(&sfilter, optval, sizeof(sfilter)))
483 if (ro->bound && ro->ifindex)
484 dev = dev_get_by_index(&init_net, ro->ifindex);
487 /* (try to) register the new filters */
489 err = raw_enable_filters(dev, sk, &sfilter, 1);
491 err = raw_enable_filters(dev, sk, filter,
499 /* remove old filter registrations */
500 raw_disable_filters(dev, sk, ro->filter, ro->count);
503 /* remove old filter space */
507 /* link new filters to the socket */
509 /* copy filter data for single filter */
510 ro->dfilter = sfilter;
511 filter = &ro->dfilter;
524 case CAN_RAW_ERR_FILTER:
525 if (optlen != sizeof(err_mask))
528 if (copy_from_user(&err_mask, optval, optlen))
531 err_mask &= CAN_ERR_MASK;
535 if (ro->bound && ro->ifindex)
536 dev = dev_get_by_index(&init_net, ro->ifindex);
538 /* remove current error mask */
540 /* (try to) register the new err_mask */
541 err = raw_enable_errfilter(dev, sk, err_mask);
546 /* remove old err_mask registration */
547 raw_disable_errfilter(dev, sk, ro->err_mask);
550 /* link new err_mask to the socket */
551 ro->err_mask = err_mask;
561 case CAN_RAW_LOOPBACK:
562 if (optlen != sizeof(ro->loopback))
565 if (copy_from_user(&ro->loopback, optval, optlen))
570 case CAN_RAW_RECV_OWN_MSGS:
571 if (optlen != sizeof(ro->recv_own_msgs))
574 if (copy_from_user(&ro->recv_own_msgs, optval, optlen))
579 case CAN_RAW_FD_FRAMES:
580 if (optlen != sizeof(ro->fd_frames))
583 if (copy_from_user(&ro->fd_frames, optval, optlen))
594 static int raw_getsockopt(struct socket *sock, int level, int optname,
595 char __user *optval, int __user *optlen)
597 struct sock *sk = sock->sk;
598 struct raw_sock *ro = raw_sk(sk);
603 if (level != SOL_CAN_RAW)
605 if (get_user(len, optlen))
615 int fsize = ro->count * sizeof(struct can_filter);
618 if (copy_to_user(optval, ro->filter, len))
625 err = put_user(len, optlen);
628 case CAN_RAW_ERR_FILTER:
629 if (len > sizeof(can_err_mask_t))
630 len = sizeof(can_err_mask_t);
634 case CAN_RAW_LOOPBACK:
635 if (len > sizeof(int))
640 case CAN_RAW_RECV_OWN_MSGS:
641 if (len > sizeof(int))
643 val = &ro->recv_own_msgs;
646 case CAN_RAW_FD_FRAMES:
647 if (len > sizeof(int))
649 val = &ro->fd_frames;
656 if (put_user(len, optlen))
658 if (copy_to_user(optval, val, len))
663 static int raw_sendmsg(struct kiocb *iocb, struct socket *sock,
664 struct msghdr *msg, size_t size)
666 struct sock *sk = sock->sk;
667 struct raw_sock *ro = raw_sk(sk);
669 struct net_device *dev;
674 DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name);
676 if (msg->msg_namelen < sizeof(*addr))
679 if (addr->can_family != AF_CAN)
682 ifindex = addr->can_ifindex;
684 ifindex = ro->ifindex;
687 if (unlikely(size != CANFD_MTU && size != CAN_MTU))
690 if (unlikely(size != CAN_MTU))
694 dev = dev_get_by_index(&init_net, ifindex);
698 skb = sock_alloc_send_skb(sk, size + sizeof(struct can_skb_priv),
699 msg->msg_flags & MSG_DONTWAIT, &err);
703 can_skb_reserve(skb);
704 can_skb_prv(skb)->ifindex = dev->ifindex;
706 err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
710 sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
714 skb->priority = sk->sk_priority;
716 err = can_send(skb, ro->loopback);
733 static int raw_recvmsg(struct kiocb *iocb, struct socket *sock,
734 struct msghdr *msg, size_t size, int flags)
736 struct sock *sk = sock->sk;
741 noblock = flags & MSG_DONTWAIT;
742 flags &= ~MSG_DONTWAIT;
744 skb = skb_recv_datagram(sk, flags, noblock, &err);
749 msg->msg_flags |= MSG_TRUNC;
753 err = memcpy_toiovec(msg->msg_iov, skb->data, size);
755 skb_free_datagram(sk, skb);
759 sock_recv_ts_and_drops(msg, sk, skb);
762 __sockaddr_check_size(sizeof(struct sockaddr_can));
763 msg->msg_namelen = sizeof(struct sockaddr_can);
764 memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
767 /* assign the flags that have been recorded in raw_rcv() */
768 msg->msg_flags |= *(raw_flags(skb));
770 skb_free_datagram(sk, skb);
775 static const struct proto_ops raw_ops = {
777 .release = raw_release,
779 .connect = sock_no_connect,
780 .socketpair = sock_no_socketpair,
781 .accept = sock_no_accept,
782 .getname = raw_getname,
783 .poll = datagram_poll,
784 .ioctl = can_ioctl, /* use can_ioctl() from af_can.c */
785 .listen = sock_no_listen,
786 .shutdown = sock_no_shutdown,
787 .setsockopt = raw_setsockopt,
788 .getsockopt = raw_getsockopt,
789 .sendmsg = raw_sendmsg,
790 .recvmsg = raw_recvmsg,
791 .mmap = sock_no_mmap,
792 .sendpage = sock_no_sendpage,
795 static struct proto raw_proto __read_mostly = {
797 .owner = THIS_MODULE,
798 .obj_size = sizeof(struct raw_sock),
802 static const struct can_proto raw_can_proto = {
809 static __init int raw_module_init(void)
815 err = can_proto_register(&raw_can_proto);
817 printk(KERN_ERR "can: registration of raw protocol failed\n");
822 static __exit void raw_module_exit(void)
824 can_proto_unregister(&raw_can_proto);
827 module_init(raw_module_init);
828 module_exit(raw_module_exit);