1 /* 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 * Send feedback to <socketcan-users@lists.berlios.de> 41 * 42 */ 43 44 #include <linux/module.h> 45 #include <linux/init.h> 46 #include <linux/uio.h> 47 #include <linux/net.h> 48 #include <linux/slab.h> 49 #include <linux/netdevice.h> 50 #include <linux/socket.h> 51 #include <linux/if_arp.h> 52 #include <linux/skbuff.h> 53 #include <linux/can.h> 54 #include <linux/can/core.h> 55 #include <linux/can/raw.h> 56 #include <net/sock.h> 57 #include <net/net_namespace.h> 58 59 #define CAN_RAW_VERSION CAN_VERSION 60 static __initdata const char banner[] = 61 KERN_INFO "can: raw protocol (rev " CAN_RAW_VERSION ")\n"; 62 63 MODULE_DESCRIPTION("PF_CAN raw protocol"); 64 MODULE_LICENSE("Dual BSD/GPL"); 65 MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>"); 66 MODULE_ALIAS("can-proto-1"); 67 68 #define MASK_ALL 0 69 70 /* 71 * A raw socket has a list of can_filters attached to it, each receiving 72 * the CAN frames matching that filter. If the filter list is empty, 73 * no CAN frames will be received by the socket. The default after 74 * opening the socket, is to have one filter which receives all frames. 75 * The filter list is allocated dynamically with the exception of the 76 * list containing only one item. This common case is optimized by 77 * storing the single filter in dfilter, to avoid using dynamic memory. 78 */ 79 80 struct raw_sock { 81 struct sock sk; 82 int bound; 83 int ifindex; 84 struct notifier_block notifier; 85 int loopback; 86 int recv_own_msgs; 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; 91 }; 92 93 /* 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' 96 * in skb->cb. 97 */ 98 static inline unsigned int *raw_flags(struct sk_buff *skb) 99 { 100 BUILD_BUG_ON(sizeof(skb->cb) <= (sizeof(struct sockaddr_can) + 101 sizeof(unsigned int))); 102 103 /* return pointer after struct sockaddr_can */ 104 return (unsigned int *)(&((struct sockaddr_can *)skb->cb)[1]); 105 } 106 107 static inline struct raw_sock *raw_sk(const struct sock *sk) 108 { 109 return (struct raw_sock *)sk; 110 } 111 112 static void raw_rcv(struct sk_buff *oskb, void *data) 113 { 114 struct sock *sk = (struct sock *)data; 115 struct raw_sock *ro = raw_sk(sk); 116 struct sockaddr_can *addr; 117 struct sk_buff *skb; 118 unsigned int *pflags; 119 120 /* check the received tx sock reference */ 121 if (!ro->recv_own_msgs && oskb->sk == sk) 122 return; 123 124 /* clone the given skb to be able to enqueue it into the rcv queue */ 125 skb = skb_clone(oskb, GFP_ATOMIC); 126 if (!skb) 127 return; 128 129 /* 130 * Put the datagram to the queue so that raw_recvmsg() can 131 * get it from there. We need to pass the interface index to 132 * raw_recvmsg(). We pass a whole struct sockaddr_can in skb->cb 133 * containing the interface index. 134 */ 135 136 BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct sockaddr_can)); 137 addr = (struct sockaddr_can *)skb->cb; 138 memset(addr, 0, sizeof(*addr)); 139 addr->can_family = AF_CAN; 140 addr->can_ifindex = skb->dev->ifindex; 141 142 /* add CAN specific message flags for raw_recvmsg() */ 143 pflags = raw_flags(skb); 144 *pflags = 0; 145 if (oskb->sk) 146 *pflags |= MSG_DONTROUTE; 147 if (oskb->sk == sk) 148 *pflags |= MSG_CONFIRM; 149 150 if (sock_queue_rcv_skb(sk, skb) < 0) 151 kfree_skb(skb); 152 } 153 154 static int raw_enable_filters(struct net_device *dev, struct sock *sk, 155 struct can_filter *filter, int count) 156 { 157 int err = 0; 158 int i; 159 160 for (i = 0; i < count; i++) { 161 err = can_rx_register(dev, filter[i].can_id, 162 filter[i].can_mask, 163 raw_rcv, sk, "raw"); 164 if (err) { 165 /* clean up successfully registered filters */ 166 while (--i >= 0) 167 can_rx_unregister(dev, filter[i].can_id, 168 filter[i].can_mask, 169 raw_rcv, sk); 170 break; 171 } 172 } 173 174 return err; 175 } 176 177 static int raw_enable_errfilter(struct net_device *dev, struct sock *sk, 178 can_err_mask_t err_mask) 179 { 180 int err = 0; 181 182 if (err_mask) 183 err = can_rx_register(dev, 0, err_mask | CAN_ERR_FLAG, 184 raw_rcv, sk, "raw"); 185 186 return err; 187 } 188 189 static void raw_disable_filters(struct net_device *dev, struct sock *sk, 190 struct can_filter *filter, int count) 191 { 192 int i; 193 194 for (i = 0; i < count; i++) 195 can_rx_unregister(dev, filter[i].can_id, filter[i].can_mask, 196 raw_rcv, sk); 197 } 198 199 static inline void raw_disable_errfilter(struct net_device *dev, 200 struct sock *sk, 201 can_err_mask_t err_mask) 202 203 { 204 if (err_mask) 205 can_rx_unregister(dev, 0, err_mask | CAN_ERR_FLAG, 206 raw_rcv, sk); 207 } 208 209 static inline void raw_disable_allfilters(struct net_device *dev, 210 struct sock *sk) 211 { 212 struct raw_sock *ro = raw_sk(sk); 213 214 raw_disable_filters(dev, sk, ro->filter, ro->count); 215 raw_disable_errfilter(dev, sk, ro->err_mask); 216 } 217 218 static int raw_enable_allfilters(struct net_device *dev, struct sock *sk) 219 { 220 struct raw_sock *ro = raw_sk(sk); 221 int err; 222 223 err = raw_enable_filters(dev, sk, ro->filter, ro->count); 224 if (!err) { 225 err = raw_enable_errfilter(dev, sk, ro->err_mask); 226 if (err) 227 raw_disable_filters(dev, sk, ro->filter, ro->count); 228 } 229 230 return err; 231 } 232 233 static int raw_notifier(struct notifier_block *nb, 234 unsigned long msg, void *data) 235 { 236 struct net_device *dev = (struct net_device *)data; 237 struct raw_sock *ro = container_of(nb, struct raw_sock, notifier); 238 struct sock *sk = &ro->sk; 239 240 if (!net_eq(dev_net(dev), &init_net)) 241 return NOTIFY_DONE; 242 243 if (dev->type != ARPHRD_CAN) 244 return NOTIFY_DONE; 245 246 if (ro->ifindex != dev->ifindex) 247 return NOTIFY_DONE; 248 249 switch (msg) { 250 251 case NETDEV_UNREGISTER: 252 lock_sock(sk); 253 /* remove current filters & unregister */ 254 if (ro->bound) 255 raw_disable_allfilters(dev, sk); 256 257 if (ro->count > 1) 258 kfree(ro->filter); 259 260 ro->ifindex = 0; 261 ro->bound = 0; 262 ro->count = 0; 263 release_sock(sk); 264 265 sk->sk_err = ENODEV; 266 if (!sock_flag(sk, SOCK_DEAD)) 267 sk->sk_error_report(sk); 268 break; 269 270 case NETDEV_DOWN: 271 sk->sk_err = ENETDOWN; 272 if (!sock_flag(sk, SOCK_DEAD)) 273 sk->sk_error_report(sk); 274 break; 275 } 276 277 return NOTIFY_DONE; 278 } 279 280 static int raw_init(struct sock *sk) 281 { 282 struct raw_sock *ro = raw_sk(sk); 283 284 ro->bound = 0; 285 ro->ifindex = 0; 286 287 /* set default filter to single entry dfilter */ 288 ro->dfilter.can_id = 0; 289 ro->dfilter.can_mask = MASK_ALL; 290 ro->filter = &ro->dfilter; 291 ro->count = 1; 292 293 /* set default loopback behaviour */ 294 ro->loopback = 1; 295 ro->recv_own_msgs = 0; 296 297 /* set notifier */ 298 ro->notifier.notifier_call = raw_notifier; 299 300 register_netdevice_notifier(&ro->notifier); 301 302 return 0; 303 } 304 305 static int raw_release(struct socket *sock) 306 { 307 struct sock *sk = sock->sk; 308 struct raw_sock *ro = raw_sk(sk); 309 310 unregister_netdevice_notifier(&ro->notifier); 311 312 lock_sock(sk); 313 314 /* remove current filters & unregister */ 315 if (ro->bound) { 316 if (ro->ifindex) { 317 struct net_device *dev; 318 319 dev = dev_get_by_index(&init_net, ro->ifindex); 320 if (dev) { 321 raw_disable_allfilters(dev, sk); 322 dev_put(dev); 323 } 324 } else 325 raw_disable_allfilters(NULL, sk); 326 } 327 328 if (ro->count > 1) 329 kfree(ro->filter); 330 331 ro->ifindex = 0; 332 ro->bound = 0; 333 ro->count = 0; 334 335 sock_orphan(sk); 336 sock->sk = NULL; 337 338 release_sock(sk); 339 sock_put(sk); 340 341 return 0; 342 } 343 344 static int raw_bind(struct socket *sock, struct sockaddr *uaddr, int len) 345 { 346 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; 347 struct sock *sk = sock->sk; 348 struct raw_sock *ro = raw_sk(sk); 349 int ifindex; 350 int err = 0; 351 int notify_enetdown = 0; 352 353 if (len < sizeof(*addr)) 354 return -EINVAL; 355 356 lock_sock(sk); 357 358 if (ro->bound && addr->can_ifindex == ro->ifindex) 359 goto out; 360 361 if (addr->can_ifindex) { 362 struct net_device *dev; 363 364 dev = dev_get_by_index(&init_net, addr->can_ifindex); 365 if (!dev) { 366 err = -ENODEV; 367 goto out; 368 } 369 if (dev->type != ARPHRD_CAN) { 370 dev_put(dev); 371 err = -ENODEV; 372 goto out; 373 } 374 if (!(dev->flags & IFF_UP)) 375 notify_enetdown = 1; 376 377 ifindex = dev->ifindex; 378 379 /* filters set by default/setsockopt */ 380 err = raw_enable_allfilters(dev, sk); 381 dev_put(dev); 382 } else { 383 ifindex = 0; 384 385 /* filters set by default/setsockopt */ 386 err = raw_enable_allfilters(NULL, sk); 387 } 388 389 if (!err) { 390 if (ro->bound) { 391 /* unregister old filters */ 392 if (ro->ifindex) { 393 struct net_device *dev; 394 395 dev = dev_get_by_index(&init_net, ro->ifindex); 396 if (dev) { 397 raw_disable_allfilters(dev, sk); 398 dev_put(dev); 399 } 400 } else 401 raw_disable_allfilters(NULL, sk); 402 } 403 ro->ifindex = ifindex; 404 ro->bound = 1; 405 } 406 407 out: 408 release_sock(sk); 409 410 if (notify_enetdown) { 411 sk->sk_err = ENETDOWN; 412 if (!sock_flag(sk, SOCK_DEAD)) 413 sk->sk_error_report(sk); 414 } 415 416 return err; 417 } 418 419 static int raw_getname(struct socket *sock, struct sockaddr *uaddr, 420 int *len, int peer) 421 { 422 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; 423 struct sock *sk = sock->sk; 424 struct raw_sock *ro = raw_sk(sk); 425 426 if (peer) 427 return -EOPNOTSUPP; 428 429 memset(addr, 0, sizeof(*addr)); 430 addr->can_family = AF_CAN; 431 addr->can_ifindex = ro->ifindex; 432 433 *len = sizeof(*addr); 434 435 return 0; 436 } 437 438 static int raw_setsockopt(struct socket *sock, int level, int optname, 439 char __user *optval, unsigned int optlen) 440 { 441 struct sock *sk = sock->sk; 442 struct raw_sock *ro = raw_sk(sk); 443 struct can_filter *filter = NULL; /* dyn. alloc'ed filters */ 444 struct can_filter sfilter; /* single filter */ 445 struct net_device *dev = NULL; 446 can_err_mask_t err_mask = 0; 447 int count = 0; 448 int err = 0; 449 450 if (level != SOL_CAN_RAW) 451 return -EINVAL; 452 453 switch (optname) { 454 455 case CAN_RAW_FILTER: 456 if (optlen % sizeof(struct can_filter) != 0) 457 return -EINVAL; 458 459 count = optlen / sizeof(struct can_filter); 460 461 if (count > 1) { 462 /* filter does not fit into dfilter => alloc space */ 463 filter = memdup_user(optval, optlen); 464 if (IS_ERR(filter)) 465 return PTR_ERR(filter); 466 } else if (count == 1) { 467 if (copy_from_user(&sfilter, optval, sizeof(sfilter))) 468 return -EFAULT; 469 } 470 471 lock_sock(sk); 472 473 if (ro->bound && ro->ifindex) 474 dev = dev_get_by_index(&init_net, ro->ifindex); 475 476 if (ro->bound) { 477 /* (try to) register the new filters */ 478 if (count == 1) 479 err = raw_enable_filters(dev, sk, &sfilter, 1); 480 else 481 err = raw_enable_filters(dev, sk, filter, 482 count); 483 if (err) { 484 if (count > 1) 485 kfree(filter); 486 goto out_fil; 487 } 488 489 /* remove old filter registrations */ 490 raw_disable_filters(dev, sk, ro->filter, ro->count); 491 } 492 493 /* remove old filter space */ 494 if (ro->count > 1) 495 kfree(ro->filter); 496 497 /* link new filters to the socket */ 498 if (count == 1) { 499 /* copy filter data for single filter */ 500 ro->dfilter = sfilter; 501 filter = &ro->dfilter; 502 } 503 ro->filter = filter; 504 ro->count = count; 505 506 out_fil: 507 if (dev) 508 dev_put(dev); 509 510 release_sock(sk); 511 512 break; 513 514 case CAN_RAW_ERR_FILTER: 515 if (optlen != sizeof(err_mask)) 516 return -EINVAL; 517 518 if (copy_from_user(&err_mask, optval, optlen)) 519 return -EFAULT; 520 521 err_mask &= CAN_ERR_MASK; 522 523 lock_sock(sk); 524 525 if (ro->bound && ro->ifindex) 526 dev = dev_get_by_index(&init_net, ro->ifindex); 527 528 /* remove current error mask */ 529 if (ro->bound) { 530 /* (try to) register the new err_mask */ 531 err = raw_enable_errfilter(dev, sk, err_mask); 532 533 if (err) 534 goto out_err; 535 536 /* remove old err_mask registration */ 537 raw_disable_errfilter(dev, sk, ro->err_mask); 538 } 539 540 /* link new err_mask to the socket */ 541 ro->err_mask = err_mask; 542 543 out_err: 544 if (dev) 545 dev_put(dev); 546 547 release_sock(sk); 548 549 break; 550 551 case CAN_RAW_LOOPBACK: 552 if (optlen != sizeof(ro->loopback)) 553 return -EINVAL; 554 555 if (copy_from_user(&ro->loopback, optval, optlen)) 556 return -EFAULT; 557 558 break; 559 560 case CAN_RAW_RECV_OWN_MSGS: 561 if (optlen != sizeof(ro->recv_own_msgs)) 562 return -EINVAL; 563 564 if (copy_from_user(&ro->recv_own_msgs, optval, optlen)) 565 return -EFAULT; 566 567 break; 568 569 default: 570 return -ENOPROTOOPT; 571 } 572 return err; 573 } 574 575 static int raw_getsockopt(struct socket *sock, int level, int optname, 576 char __user *optval, int __user *optlen) 577 { 578 struct sock *sk = sock->sk; 579 struct raw_sock *ro = raw_sk(sk); 580 int len; 581 void *val; 582 int err = 0; 583 584 if (level != SOL_CAN_RAW) 585 return -EINVAL; 586 if (get_user(len, optlen)) 587 return -EFAULT; 588 if (len < 0) 589 return -EINVAL; 590 591 switch (optname) { 592 593 case CAN_RAW_FILTER: 594 lock_sock(sk); 595 if (ro->count > 0) { 596 int fsize = ro->count * sizeof(struct can_filter); 597 if (len > fsize) 598 len = fsize; 599 if (copy_to_user(optval, ro->filter, len)) 600 err = -EFAULT; 601 } else 602 len = 0; 603 release_sock(sk); 604 605 if (!err) 606 err = put_user(len, optlen); 607 return err; 608 609 case CAN_RAW_ERR_FILTER: 610 if (len > sizeof(can_err_mask_t)) 611 len = sizeof(can_err_mask_t); 612 val = &ro->err_mask; 613 break; 614 615 case CAN_RAW_LOOPBACK: 616 if (len > sizeof(int)) 617 len = sizeof(int); 618 val = &ro->loopback; 619 break; 620 621 case CAN_RAW_RECV_OWN_MSGS: 622 if (len > sizeof(int)) 623 len = sizeof(int); 624 val = &ro->recv_own_msgs; 625 break; 626 627 default: 628 return -ENOPROTOOPT; 629 } 630 631 if (put_user(len, optlen)) 632 return -EFAULT; 633 if (copy_to_user(optval, val, len)) 634 return -EFAULT; 635 return 0; 636 } 637 638 static int raw_sendmsg(struct kiocb *iocb, struct socket *sock, 639 struct msghdr *msg, size_t size) 640 { 641 struct sock *sk = sock->sk; 642 struct raw_sock *ro = raw_sk(sk); 643 struct sk_buff *skb; 644 struct net_device *dev; 645 int ifindex; 646 int err; 647 648 if (msg->msg_name) { 649 struct sockaddr_can *addr = 650 (struct sockaddr_can *)msg->msg_name; 651 652 if (msg->msg_namelen < sizeof(*addr)) 653 return -EINVAL; 654 655 if (addr->can_family != AF_CAN) 656 return -EINVAL; 657 658 ifindex = addr->can_ifindex; 659 } else 660 ifindex = ro->ifindex; 661 662 if (size != sizeof(struct can_frame)) 663 return -EINVAL; 664 665 dev = dev_get_by_index(&init_net, ifindex); 666 if (!dev) 667 return -ENXIO; 668 669 skb = sock_alloc_send_skb(sk, size, msg->msg_flags & MSG_DONTWAIT, 670 &err); 671 if (!skb) 672 goto put_dev; 673 674 err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size); 675 if (err < 0) 676 goto free_skb; 677 err = sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags); 678 if (err < 0) 679 goto free_skb; 680 681 /* to be able to check the received tx sock reference in raw_rcv() */ 682 skb_shinfo(skb)->tx_flags |= SKBTX_DRV_NEEDS_SK_REF; 683 684 skb->dev = dev; 685 skb->sk = sk; 686 687 err = can_send(skb, ro->loopback); 688 689 dev_put(dev); 690 691 if (err) 692 goto send_failed; 693 694 return size; 695 696 free_skb: 697 kfree_skb(skb); 698 put_dev: 699 dev_put(dev); 700 send_failed: 701 return err; 702 } 703 704 static int raw_recvmsg(struct kiocb *iocb, struct socket *sock, 705 struct msghdr *msg, size_t size, int flags) 706 { 707 struct sock *sk = sock->sk; 708 struct sk_buff *skb; 709 int err = 0; 710 int noblock; 711 712 noblock = flags & MSG_DONTWAIT; 713 flags &= ~MSG_DONTWAIT; 714 715 skb = skb_recv_datagram(sk, flags, noblock, &err); 716 if (!skb) 717 return err; 718 719 if (size < skb->len) 720 msg->msg_flags |= MSG_TRUNC; 721 else 722 size = skb->len; 723 724 err = memcpy_toiovec(msg->msg_iov, skb->data, size); 725 if (err < 0) { 726 skb_free_datagram(sk, skb); 727 return err; 728 } 729 730 sock_recv_ts_and_drops(msg, sk, skb); 731 732 if (msg->msg_name) { 733 msg->msg_namelen = sizeof(struct sockaddr_can); 734 memcpy(msg->msg_name, skb->cb, msg->msg_namelen); 735 } 736 737 /* assign the flags that have been recorded in raw_rcv() */ 738 msg->msg_flags |= *(raw_flags(skb)); 739 740 skb_free_datagram(sk, skb); 741 742 return size; 743 } 744 745 static const struct proto_ops raw_ops = { 746 .family = PF_CAN, 747 .release = raw_release, 748 .bind = raw_bind, 749 .connect = sock_no_connect, 750 .socketpair = sock_no_socketpair, 751 .accept = sock_no_accept, 752 .getname = raw_getname, 753 .poll = datagram_poll, 754 .ioctl = can_ioctl, /* use can_ioctl() from af_can.c */ 755 .listen = sock_no_listen, 756 .shutdown = sock_no_shutdown, 757 .setsockopt = raw_setsockopt, 758 .getsockopt = raw_getsockopt, 759 .sendmsg = raw_sendmsg, 760 .recvmsg = raw_recvmsg, 761 .mmap = sock_no_mmap, 762 .sendpage = sock_no_sendpage, 763 }; 764 765 static struct proto raw_proto __read_mostly = { 766 .name = "CAN_RAW", 767 .owner = THIS_MODULE, 768 .obj_size = sizeof(struct raw_sock), 769 .init = raw_init, 770 }; 771 772 static struct can_proto raw_can_proto __read_mostly = { 773 .type = SOCK_RAW, 774 .protocol = CAN_RAW, 775 .ops = &raw_ops, 776 .prot = &raw_proto, 777 }; 778 779 static __init int raw_module_init(void) 780 { 781 int err; 782 783 printk(banner); 784 785 err = can_proto_register(&raw_can_proto); 786 if (err < 0) 787 printk(KERN_ERR "can: registration of raw protocol failed\n"); 788 789 return err; 790 } 791 792 static __exit void raw_module_exit(void) 793 { 794 can_proto_unregister(&raw_can_proto); 795 } 796 797 module_init(raw_module_init); 798 module_exit(raw_module_exit); 799