xfs: fix locking in xfs_iget_cache_hit
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / net / can / raw.c
blobf4cc44548bdaa35a2b6947b8c7ef89affe8ac615
1 /*
2 * raw.c - Raw sockets for protocol family CAN
4 * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
5 * All rights reserved.
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.
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
38 * DAMAGE.
40 * Send feedback to <socketcan-users@lists.berlios.de>
44 #include <linux/module.h>
45 #include <linux/init.h>
46 #include <linux/uio.h>
47 #include <linux/net.h>
48 #include <linux/netdevice.h>
49 #include <linux/socket.h>
50 #include <linux/if_arp.h>
51 #include <linux/skbuff.h>
52 #include <linux/can.h>
53 #include <linux/can/core.h>
54 #include <linux/can/raw.h>
55 #include <net/sock.h>
56 #include <net/net_namespace.h>
58 #define CAN_RAW_VERSION CAN_VERSION
59 static __initdata 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");
64 MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>");
65 MODULE_ALIAS("can-proto-1");
67 #define MASK_ALL 0
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.
79 struct raw_sock {
80 struct sock sk;
81 int bound;
82 int ifindex;
83 struct notifier_block notifier;
84 int loopback;
85 int recv_own_msgs;
86 int count; /* number of active filters */
87 struct can_filter dfilter; /* default/single filter */
88 struct can_filter *filter; /* pointer to filter(s) */
89 can_err_mask_t err_mask;
92 static inline struct raw_sock *raw_sk(const struct sock *sk)
94 return (struct raw_sock *)sk;
97 static void raw_rcv(struct sk_buff *skb, void *data)
99 struct sock *sk = (struct sock *)data;
100 struct raw_sock *ro = raw_sk(sk);
101 struct sockaddr_can *addr;
103 /* check the received tx sock reference */
104 if (!ro->recv_own_msgs && skb->sk == sk)
105 return;
107 /* clone the given skb to be able to enqueue it into the rcv queue */
108 skb = skb_clone(skb, GFP_ATOMIC);
109 if (!skb)
110 return;
113 * Put the datagram to the queue so that raw_recvmsg() can
114 * get it from there. We need to pass the interface index to
115 * raw_recvmsg(). We pass a whole struct sockaddr_can in skb->cb
116 * containing the interface index.
119 BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct sockaddr_can));
120 addr = (struct sockaddr_can *)skb->cb;
121 memset(addr, 0, sizeof(*addr));
122 addr->can_family = AF_CAN;
123 addr->can_ifindex = skb->dev->ifindex;
125 if (sock_queue_rcv_skb(sk, skb) < 0)
126 kfree_skb(skb);
129 static int raw_enable_filters(struct net_device *dev, struct sock *sk,
130 struct can_filter *filter, int count)
132 int err = 0;
133 int i;
135 for (i = 0; i < count; i++) {
136 err = can_rx_register(dev, filter[i].can_id,
137 filter[i].can_mask,
138 raw_rcv, sk, "raw");
139 if (err) {
140 /* clean up successfully registered filters */
141 while (--i >= 0)
142 can_rx_unregister(dev, filter[i].can_id,
143 filter[i].can_mask,
144 raw_rcv, sk);
145 break;
149 return err;
152 static int raw_enable_errfilter(struct net_device *dev, struct sock *sk,
153 can_err_mask_t err_mask)
155 int err = 0;
157 if (err_mask)
158 err = can_rx_register(dev, 0, err_mask | CAN_ERR_FLAG,
159 raw_rcv, sk, "raw");
161 return err;
164 static void raw_disable_filters(struct net_device *dev, struct sock *sk,
165 struct can_filter *filter, int count)
167 int i;
169 for (i = 0; i < count; i++)
170 can_rx_unregister(dev, filter[i].can_id, filter[i].can_mask,
171 raw_rcv, sk);
174 static inline void raw_disable_errfilter(struct net_device *dev,
175 struct sock *sk,
176 can_err_mask_t err_mask)
179 if (err_mask)
180 can_rx_unregister(dev, 0, err_mask | CAN_ERR_FLAG,
181 raw_rcv, sk);
184 static inline void raw_disable_allfilters(struct net_device *dev,
185 struct sock *sk)
187 struct raw_sock *ro = raw_sk(sk);
189 raw_disable_filters(dev, sk, ro->filter, ro->count);
190 raw_disable_errfilter(dev, sk, ro->err_mask);
193 static int raw_enable_allfilters(struct net_device *dev, struct sock *sk)
195 struct raw_sock *ro = raw_sk(sk);
196 int err;
198 err = raw_enable_filters(dev, sk, ro->filter, ro->count);
199 if (!err) {
200 err = raw_enable_errfilter(dev, sk, ro->err_mask);
201 if (err)
202 raw_disable_filters(dev, sk, ro->filter, ro->count);
205 return err;
208 static int raw_notifier(struct notifier_block *nb,
209 unsigned long msg, void *data)
211 struct net_device *dev = (struct net_device *)data;
212 struct raw_sock *ro = container_of(nb, struct raw_sock, notifier);
213 struct sock *sk = &ro->sk;
215 if (!net_eq(dev_net(dev), &init_net))
216 return NOTIFY_DONE;
218 if (dev->type != ARPHRD_CAN)
219 return NOTIFY_DONE;
221 if (ro->ifindex != dev->ifindex)
222 return NOTIFY_DONE;
224 switch (msg) {
226 case NETDEV_UNREGISTER:
227 lock_sock(sk);
228 /* remove current filters & unregister */
229 if (ro->bound)
230 raw_disable_allfilters(dev, sk);
232 if (ro->count > 1)
233 kfree(ro->filter);
235 ro->ifindex = 0;
236 ro->bound = 0;
237 ro->count = 0;
238 release_sock(sk);
240 sk->sk_err = ENODEV;
241 if (!sock_flag(sk, SOCK_DEAD))
242 sk->sk_error_report(sk);
243 break;
245 case NETDEV_DOWN:
246 sk->sk_err = ENETDOWN;
247 if (!sock_flag(sk, SOCK_DEAD))
248 sk->sk_error_report(sk);
249 break;
252 return NOTIFY_DONE;
255 static int raw_init(struct sock *sk)
257 struct raw_sock *ro = raw_sk(sk);
259 ro->bound = 0;
260 ro->ifindex = 0;
262 /* set default filter to single entry dfilter */
263 ro->dfilter.can_id = 0;
264 ro->dfilter.can_mask = MASK_ALL;
265 ro->filter = &ro->dfilter;
266 ro->count = 1;
268 /* set default loopback behaviour */
269 ro->loopback = 1;
270 ro->recv_own_msgs = 0;
272 /* set notifier */
273 ro->notifier.notifier_call = raw_notifier;
275 register_netdevice_notifier(&ro->notifier);
277 return 0;
280 static int raw_release(struct socket *sock)
282 struct sock *sk = sock->sk;
283 struct raw_sock *ro = raw_sk(sk);
285 unregister_netdevice_notifier(&ro->notifier);
287 lock_sock(sk);
289 /* remove current filters & unregister */
290 if (ro->bound) {
291 if (ro->ifindex) {
292 struct net_device *dev;
294 dev = dev_get_by_index(&init_net, ro->ifindex);
295 if (dev) {
296 raw_disable_allfilters(dev, sk);
297 dev_put(dev);
299 } else
300 raw_disable_allfilters(NULL, sk);
303 if (ro->count > 1)
304 kfree(ro->filter);
306 ro->ifindex = 0;
307 ro->bound = 0;
308 ro->count = 0;
310 sock_orphan(sk);
311 sock->sk = NULL;
313 release_sock(sk);
314 sock_put(sk);
316 return 0;
319 static int raw_bind(struct socket *sock, struct sockaddr *uaddr, int len)
321 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
322 struct sock *sk = sock->sk;
323 struct raw_sock *ro = raw_sk(sk);
324 int ifindex;
325 int err = 0;
326 int notify_enetdown = 0;
328 if (len < sizeof(*addr))
329 return -EINVAL;
331 lock_sock(sk);
333 if (ro->bound && addr->can_ifindex == ro->ifindex)
334 goto out;
336 if (addr->can_ifindex) {
337 struct net_device *dev;
339 dev = dev_get_by_index(&init_net, addr->can_ifindex);
340 if (!dev) {
341 err = -ENODEV;
342 goto out;
344 if (dev->type != ARPHRD_CAN) {
345 dev_put(dev);
346 err = -ENODEV;
347 goto out;
349 if (!(dev->flags & IFF_UP))
350 notify_enetdown = 1;
352 ifindex = dev->ifindex;
354 /* filters set by default/setsockopt */
355 err = raw_enable_allfilters(dev, sk);
356 dev_put(dev);
357 } else {
358 ifindex = 0;
360 /* filters set by default/setsockopt */
361 err = raw_enable_allfilters(NULL, sk);
364 if (!err) {
365 if (ro->bound) {
366 /* unregister old filters */
367 if (ro->ifindex) {
368 struct net_device *dev;
370 dev = dev_get_by_index(&init_net, ro->ifindex);
371 if (dev) {
372 raw_disable_allfilters(dev, sk);
373 dev_put(dev);
375 } else
376 raw_disable_allfilters(NULL, sk);
378 ro->ifindex = ifindex;
379 ro->bound = 1;
382 out:
383 release_sock(sk);
385 if (notify_enetdown) {
386 sk->sk_err = ENETDOWN;
387 if (!sock_flag(sk, SOCK_DEAD))
388 sk->sk_error_report(sk);
391 return err;
394 static int raw_getname(struct socket *sock, struct sockaddr *uaddr,
395 int *len, int peer)
397 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
398 struct sock *sk = sock->sk;
399 struct raw_sock *ro = raw_sk(sk);
401 if (peer)
402 return -EOPNOTSUPP;
404 addr->can_family = AF_CAN;
405 addr->can_ifindex = ro->ifindex;
407 *len = sizeof(*addr);
409 return 0;
412 static int raw_setsockopt(struct socket *sock, int level, int optname,
413 char __user *optval, int optlen)
415 struct sock *sk = sock->sk;
416 struct raw_sock *ro = raw_sk(sk);
417 struct can_filter *filter = NULL; /* dyn. alloc'ed filters */
418 struct can_filter sfilter; /* single filter */
419 struct net_device *dev = NULL;
420 can_err_mask_t err_mask = 0;
421 int count = 0;
422 int err = 0;
424 if (level != SOL_CAN_RAW)
425 return -EINVAL;
426 if (optlen < 0)
427 return -EINVAL;
429 switch (optname) {
431 case CAN_RAW_FILTER:
432 if (optlen % sizeof(struct can_filter) != 0)
433 return -EINVAL;
435 count = optlen / sizeof(struct can_filter);
437 if (count > 1) {
438 /* filter does not fit into dfilter => alloc space */
439 filter = kmalloc(optlen, GFP_KERNEL);
440 if (!filter)
441 return -ENOMEM;
443 if (copy_from_user(filter, optval, optlen)) {
444 kfree(filter);
445 return -EFAULT;
447 } else if (count == 1) {
448 if (copy_from_user(&sfilter, optval, optlen))
449 return -EFAULT;
452 lock_sock(sk);
454 if (ro->bound && ro->ifindex)
455 dev = dev_get_by_index(&init_net, ro->ifindex);
457 if (ro->bound) {
458 /* (try to) register the new filters */
459 if (count == 1)
460 err = raw_enable_filters(dev, sk, &sfilter, 1);
461 else
462 err = raw_enable_filters(dev, sk, filter,
463 count);
464 if (err) {
465 if (count > 1)
466 kfree(filter);
467 goto out_fil;
470 /* remove old filter registrations */
471 raw_disable_filters(dev, sk, ro->filter, ro->count);
474 /* remove old filter space */
475 if (ro->count > 1)
476 kfree(ro->filter);
478 /* link new filters to the socket */
479 if (count == 1) {
480 /* copy filter data for single filter */
481 ro->dfilter = sfilter;
482 filter = &ro->dfilter;
484 ro->filter = filter;
485 ro->count = count;
487 out_fil:
488 if (dev)
489 dev_put(dev);
491 release_sock(sk);
493 break;
495 case CAN_RAW_ERR_FILTER:
496 if (optlen != sizeof(err_mask))
497 return -EINVAL;
499 if (copy_from_user(&err_mask, optval, optlen))
500 return -EFAULT;
502 err_mask &= CAN_ERR_MASK;
504 lock_sock(sk);
506 if (ro->bound && ro->ifindex)
507 dev = dev_get_by_index(&init_net, ro->ifindex);
509 /* remove current error mask */
510 if (ro->bound) {
511 /* (try to) register the new err_mask */
512 err = raw_enable_errfilter(dev, sk, err_mask);
514 if (err)
515 goto out_err;
517 /* remove old err_mask registration */
518 raw_disable_errfilter(dev, sk, ro->err_mask);
521 /* link new err_mask to the socket */
522 ro->err_mask = err_mask;
524 out_err:
525 if (dev)
526 dev_put(dev);
528 release_sock(sk);
530 break;
532 case CAN_RAW_LOOPBACK:
533 if (optlen != sizeof(ro->loopback))
534 return -EINVAL;
536 if (copy_from_user(&ro->loopback, optval, optlen))
537 return -EFAULT;
539 break;
541 case CAN_RAW_RECV_OWN_MSGS:
542 if (optlen != sizeof(ro->recv_own_msgs))
543 return -EINVAL;
545 if (copy_from_user(&ro->recv_own_msgs, optval, optlen))
546 return -EFAULT;
548 break;
550 default:
551 return -ENOPROTOOPT;
553 return err;
556 static int raw_getsockopt(struct socket *sock, int level, int optname,
557 char __user *optval, int __user *optlen)
559 struct sock *sk = sock->sk;
560 struct raw_sock *ro = raw_sk(sk);
561 int len;
562 void *val;
563 int err = 0;
565 if (level != SOL_CAN_RAW)
566 return -EINVAL;
567 if (get_user(len, optlen))
568 return -EFAULT;
569 if (len < 0)
570 return -EINVAL;
572 switch (optname) {
574 case CAN_RAW_FILTER:
575 lock_sock(sk);
576 if (ro->count > 0) {
577 int fsize = ro->count * sizeof(struct can_filter);
578 if (len > fsize)
579 len = fsize;
580 if (copy_to_user(optval, ro->filter, len))
581 err = -EFAULT;
582 } else
583 len = 0;
584 release_sock(sk);
586 if (!err)
587 err = put_user(len, optlen);
588 return err;
590 case CAN_RAW_ERR_FILTER:
591 if (len > sizeof(can_err_mask_t))
592 len = sizeof(can_err_mask_t);
593 val = &ro->err_mask;
594 break;
596 case CAN_RAW_LOOPBACK:
597 if (len > sizeof(int))
598 len = sizeof(int);
599 val = &ro->loopback;
600 break;
602 case CAN_RAW_RECV_OWN_MSGS:
603 if (len > sizeof(int))
604 len = sizeof(int);
605 val = &ro->recv_own_msgs;
606 break;
608 default:
609 return -ENOPROTOOPT;
612 if (put_user(len, optlen))
613 return -EFAULT;
614 if (copy_to_user(optval, val, len))
615 return -EFAULT;
616 return 0;
619 static int raw_sendmsg(struct kiocb *iocb, struct socket *sock,
620 struct msghdr *msg, size_t size)
622 struct sock *sk = sock->sk;
623 struct raw_sock *ro = raw_sk(sk);
624 struct sk_buff *skb;
625 struct net_device *dev;
626 int ifindex;
627 int err;
629 if (msg->msg_name) {
630 struct sockaddr_can *addr =
631 (struct sockaddr_can *)msg->msg_name;
633 if (addr->can_family != AF_CAN)
634 return -EINVAL;
636 ifindex = addr->can_ifindex;
637 } else
638 ifindex = ro->ifindex;
640 if (size != sizeof(struct can_frame))
641 return -EINVAL;
643 dev = dev_get_by_index(&init_net, ifindex);
644 if (!dev)
645 return -ENXIO;
647 skb = sock_alloc_send_skb(sk, size, msg->msg_flags & MSG_DONTWAIT,
648 &err);
649 if (!skb)
650 goto put_dev;
652 err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
653 if (err < 0)
654 goto free_skb;
655 err = sock_tx_timestamp(msg, sk, skb_tx(skb));
656 if (err < 0)
657 goto free_skb;
658 skb->dev = dev;
659 skb->sk = sk;
661 err = can_send(skb, ro->loopback);
663 dev_put(dev);
665 if (err)
666 goto send_failed;
668 return size;
670 free_skb:
671 kfree_skb(skb);
672 put_dev:
673 dev_put(dev);
674 send_failed:
675 return err;
678 static int raw_recvmsg(struct kiocb *iocb, struct socket *sock,
679 struct msghdr *msg, size_t size, int flags)
681 struct sock *sk = sock->sk;
682 struct sk_buff *skb;
683 int err = 0;
684 int noblock;
686 noblock = flags & MSG_DONTWAIT;
687 flags &= ~MSG_DONTWAIT;
689 skb = skb_recv_datagram(sk, flags, noblock, &err);
690 if (!skb)
691 return err;
693 if (size < skb->len)
694 msg->msg_flags |= MSG_TRUNC;
695 else
696 size = skb->len;
698 err = memcpy_toiovec(msg->msg_iov, skb->data, size);
699 if (err < 0) {
700 skb_free_datagram(sk, skb);
701 return err;
704 sock_recv_timestamp(msg, sk, skb);
706 if (msg->msg_name) {
707 msg->msg_namelen = sizeof(struct sockaddr_can);
708 memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
711 skb_free_datagram(sk, skb);
713 return size;
716 static struct proto_ops raw_ops __read_mostly = {
717 .family = PF_CAN,
718 .release = raw_release,
719 .bind = raw_bind,
720 .connect = sock_no_connect,
721 .socketpair = sock_no_socketpair,
722 .accept = sock_no_accept,
723 .getname = raw_getname,
724 .poll = datagram_poll,
725 .ioctl = NULL, /* use can_ioctl() from af_can.c */
726 .listen = sock_no_listen,
727 .shutdown = sock_no_shutdown,
728 .setsockopt = raw_setsockopt,
729 .getsockopt = raw_getsockopt,
730 .sendmsg = raw_sendmsg,
731 .recvmsg = raw_recvmsg,
732 .mmap = sock_no_mmap,
733 .sendpage = sock_no_sendpage,
736 static struct proto raw_proto __read_mostly = {
737 .name = "CAN_RAW",
738 .owner = THIS_MODULE,
739 .obj_size = sizeof(struct raw_sock),
740 .init = raw_init,
743 static struct can_proto raw_can_proto __read_mostly = {
744 .type = SOCK_RAW,
745 .protocol = CAN_RAW,
746 .capability = -1,
747 .ops = &raw_ops,
748 .prot = &raw_proto,
751 static __init int raw_module_init(void)
753 int err;
755 printk(banner);
757 err = can_proto_register(&raw_can_proto);
758 if (err < 0)
759 printk(KERN_ERR "can: registration of raw protocol failed\n");
761 return err;
764 static __exit void raw_module_exit(void)
766 can_proto_unregister(&raw_can_proto);
769 module_init(raw_module_init);
770 module_exit(raw_module_exit);