net/can/raw.c

   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  */
  41
  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>
  55 #include <net/sock.h>
  56 #include <net/net_namespace.h>
  57
  58 #define CAN_RAW_VERSION CAN_VERSION
  59
  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");
  64
  65 #define MASK_ALL 0
  66
  67 /*
  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.
  75  */
  76
  77 struct raw_sock {
  78         struct sock sk;
  79         int bound;
  80         int ifindex;
  81         struct notifier_block notifier;
  82         int loopback;
  83         int recv_own_msgs;
  84         int fd_frames;
  85         int count;                 /* number of active filters */
  86         struct can_filter dfilter; /* default/single filter */
  87         struct can_filter *filter; /* pointer to filter(s) */
  88         can_err_mask_t err_mask;
  89 };
  90
  91 /*
  92  * Return pointer to store the extra msg flags for raw_recvmsg().
  93  * We use the space of one unsigned int beyond the 'struct sockaddr_can'
  94  * in skb->cb.
  95  */
  96 static inline unsigned int *raw_flags(struct sk_buff *skb)
  97 {
  98         sock_skb_cb_check_size(sizeof(struct sockaddr_can) +
  99                                sizeof(unsigned int));
 100
 101         /* return pointer after struct sockaddr_can */
 102         return (unsigned int *)(&((struct sockaddr_can *)skb->cb)[1]);
 103 }
 104
 105 static inline struct raw_sock *raw_sk(const struct sock *sk)
 106 {
 107         return (struct raw_sock *)sk;
 108 }
 109
 110 static void raw_rcv(struct sk_buff *oskb, void *data)
 111 {
 112         struct sock *sk = (struct sock *)data;
 113         struct raw_sock *ro = raw_sk(sk);
 114         struct sockaddr_can *addr;
 115         struct sk_buff *skb;
 116         unsigned int *pflags;
 117
 118         /* check the received tx sock reference */
 119         if (!ro->recv_own_msgs && oskb->sk == sk)
 120                 return;
 121
 122         /* do not pass non-CAN2.0 frames to a legacy socket */
 123         if (!ro->fd_frames && oskb->len != CAN_MTU)
 124                 return;
 125
 126         /* clone the given skb to be able to enqueue it into the rcv queue */
 127         skb = skb_clone(oskb, GFP_ATOMIC);
 128         if (!skb)
 129                 return;
 130
 131         /*
 132          *  Put the datagram to the queue so that raw_recvmsg() can
 133          *  get it from there.  We need to pass the interface index to
 134          *  raw_recvmsg().  We pass a whole struct sockaddr_can in skb->cb
 135          *  containing the interface index.
 136          */
 137
 138         sock_skb_cb_check_size(sizeof(struct sockaddr_can));
 139         addr = (struct sockaddr_can *)skb->cb;
 140         memset(addr, 0, sizeof(*addr));
 141         addr->can_family  = AF_CAN;
 142         addr->can_ifindex = skb->dev->ifindex;
 143
 144         /* add CAN specific message flags for raw_recvmsg() */
 145         pflags = raw_flags(skb);
 146         *pflags = 0;
 147         if (oskb->sk)
 148                 *pflags |= MSG_DONTROUTE;
 149         if (oskb->sk == sk)
 150                 *pflags |= MSG_CONFIRM;
 151
 152         if (sock_queue_rcv_skb(sk, skb) < 0)
 153                 kfree_skb(skb);
 154 }
 155
 156 static int raw_enable_filters(struct net_device *dev, struct sock *sk,
 157                               struct can_filter *filter, int count)
 158 {
 159         int err = 0;
 160         int i;
 161
 162         for (i = 0; i < count; i++) {
 163                 err = can_rx_register(dev, filter[i].can_id,
 164                                       filter[i].can_mask,
 165                                       raw_rcv, sk, "raw");
 166                 if (err) {
 167                         /* clean up successfully registered filters */
 168                         while (--i >= 0)
 169                                 can_rx_unregister(dev, filter[i].can_id,
 170                                                   filter[i].can_mask,
 171                                                   raw_rcv, sk);
 172                         break;
 173                 }
 174         }
 175
 176         return err;
 177 }
 178
 179 static int raw_enable_errfilter(struct net_device *dev, struct sock *sk,
 180                                 can_err_mask_t err_mask)
 181 {
 182         int err = 0;
 183
 184         if (err_mask)
 185                 err = can_rx_register(dev, 0, err_mask | CAN_ERR_FLAG,
 186                                       raw_rcv, sk, "raw");
 187
 188         return err;
 189 }
 190
 191 static void raw_disable_filters(struct net_device *dev, struct sock *sk,
 192                               struct can_filter *filter, int count)
 193 {
 194         int i;
 195
 196         for (i = 0; i < count; i++)
 197                 can_rx_unregister(dev, filter[i].can_id, filter[i].can_mask,
 198                                   raw_rcv, sk);
 199 }
 200
 201 static inline void raw_disable_errfilter(struct net_device *dev,
 202                                          struct sock *sk,
 203                                          can_err_mask_t err_mask)
 204
 205 {
 206         if (err_mask)
 207                 can_rx_unregister(dev, 0, err_mask | CAN_ERR_FLAG,
 208                                   raw_rcv, sk);
 209 }
 210
 211 static inline void raw_disable_allfilters(struct net_device *dev,
 212                                           struct sock *sk)
 213 {
 214         struct raw_sock *ro = raw_sk(sk);
 215
 216         raw_disable_filters(dev, sk, ro->filter, ro->count);
 217         raw_disable_errfilter(dev, sk, ro->err_mask);
 218 }
 219
 220 static int raw_enable_allfilters(struct net_device *dev, struct sock *sk)
 221 {
 222         struct raw_sock *ro = raw_sk(sk);
 223         int err;
 224
 225         err = raw_enable_filters(dev, sk, ro->filter, ro->count);
 226         if (!err) {
 227                 err = raw_enable_errfilter(dev, sk, ro->err_mask);
 228                 if (err)
 229                         raw_disable_filters(dev, sk, ro->filter, ro->count);
 230         }
 231
 232         return err;
 233 }
 234
 235 static int raw_notifier(struct notifier_block *nb,
 236                         unsigned long msg, void *ptr)
 237 {
 238         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 239         struct raw_sock *ro = container_of(nb, struct raw_sock, notifier);
 240         struct sock *sk = &ro->sk;
 241
 242         if (!net_eq(dev_net(dev), &init_net))
 243                 return NOTIFY_DONE;
 244
 245         if (dev->type != ARPHRD_CAN)
 246                 return NOTIFY_DONE;
 247
 248         if (ro->ifindex != dev->ifindex)
 249                 return NOTIFY_DONE;
 250
 251         switch (msg) {
 252
 253         case NETDEV_UNREGISTER:
 254                 lock_sock(sk);
 255                 /* remove current filters & unregister */
 256                 if (ro->bound)
 257                         raw_disable_allfilters(dev, sk);
 258
 259                 if (ro->count > 1)
 260                         kfree(ro->filter);
 261
 262                 ro->ifindex = 0;
 263                 ro->bound   = 0;
 264                 ro->count   = 0;
 265                 release_sock(sk);
 266
 267                 sk->sk_err = ENODEV;
 268                 if (!sock_flag(sk, SOCK_DEAD))
 269                         sk->sk_error_report(sk);
 270                 break;
 271
 272         case NETDEV_DOWN:
 273                 sk->sk_err = ENETDOWN;
 274                 if (!sock_flag(sk, SOCK_DEAD))
 275                         sk->sk_error_report(sk);
 276                 break;
 277         }
 278
 279         return NOTIFY_DONE;
 280 }
 281
 282 static int raw_init(struct sock *sk)
 283 {
 284         struct raw_sock *ro = raw_sk(sk);
 285
 286         ro->bound            = 0;
 287         ro->ifindex          = 0;
 288
 289         /* set default filter to single entry dfilter */
 290         ro->dfilter.can_id   = 0;
 291         ro->dfilter.can_mask = MASK_ALL;
 292         ro->filter           = &ro->dfilter;
 293         ro->count            = 1;
 294
 295         /* set default loopback behaviour */
 296         ro->loopback         = 1;
 297         ro->recv_own_msgs    = 0;
 298         ro->fd_frames        = 0;
 299
 300         /* set notifier */
 301         ro->notifier.notifier_call = raw_notifier;
 302
 303         register_netdevice_notifier(&ro->notifier);
 304
 305         return 0;
 306 }
 307
 308 static int raw_release(struct socket *sock)
 309 {
 310         struct sock *sk = sock->sk;
 311         struct raw_sock *ro;
 312
 313         if (!sk)
 314                 return 0;
 315
 316         ro = raw_sk(sk);
 317
 318         unregister_netdevice_notifier(&ro->notifier);
 319
 320         lock_sock(sk);
 321
 322         /* remove current filters & unregister */
 323         if (ro->bound) {
 324                 if (ro->ifindex) {
 325                         struct net_device *dev;
 326
 327                         dev = dev_get_by_index(&init_net, ro->ifindex);
 328                         if (dev) {
 329                                 raw_disable_allfilters(dev, sk);
 330                                 dev_put(dev);
 331                         }
 332                 } else
 333                         raw_disable_allfilters(NULL, sk);
 334         }
 335
 336         if (ro->count > 1)
 337                 kfree(ro->filter);
 338
 339         ro->ifindex = 0;
 340         ro->bound   = 0;
 341         ro->count   = 0;
 342
 343         sock_orphan(sk);
 344         sock->sk = NULL;
 345
 346         release_sock(sk);
 347         sock_put(sk);
 348
 349         return 0;
 350 }
 351
 352 static int raw_bind(struct socket *sock, struct sockaddr *uaddr, int len)
 353 {
 354         struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
 355         struct sock *sk = sock->sk;
 356         struct raw_sock *ro = raw_sk(sk);
 357         int ifindex;
 358         int err = 0;
 359         int notify_enetdown = 0;
 360
 361         if (len < sizeof(*addr))
 362                 return -EINVAL;
 363
 364         lock_sock(sk);
 365
 366         if (ro->bound && addr->can_ifindex == ro->ifindex)
 367                 goto out;
 368
 369         if (addr->can_ifindex) {
 370                 struct net_device *dev;
 371
 372                 dev = dev_get_by_index(&init_net, addr->can_ifindex);
 373                 if (!dev) {
 374                         err = -ENODEV;
 375                         goto out;
 376                 }
 377                 if (dev->type != ARPHRD_CAN) {
 378                         dev_put(dev);
 379                         err = -ENODEV;
 380                         goto out;
 381                 }
 382                 if (!(dev->flags & IFF_UP))
 383                         notify_enetdown = 1;
 384
 385                 ifindex = dev->ifindex;
 386
 387                 /* filters set by default/setsockopt */
 388                 err = raw_enable_allfilters(dev, sk);
 389                 dev_put(dev);
 390         } else {
 391                 ifindex = 0;
 392
 393                 /* filters set by default/setsockopt */
 394                 err = raw_enable_allfilters(NULL, sk);
 395         }
 396
 397         if (!err) {
 398                 if (ro->bound) {
 399                         /* unregister old filters */
 400                         if (ro->ifindex) {
 401                                 struct net_device *dev;
 402
 403                                 dev = dev_get_by_index(&init_net, ro->ifindex);
 404                                 if (dev) {
 405                                         raw_disable_allfilters(dev, sk);
 406                                         dev_put(dev);
 407                                 }
 408                         } else
 409                                 raw_disable_allfilters(NULL, sk);
 410                 }
 411                 ro->ifindex = ifindex;
 412                 ro->bound = 1;
 413         }
 414
 415  out:
 416         release_sock(sk);
 417
 418         if (notify_enetdown) {
 419                 sk->sk_err = ENETDOWN;
 420                 if (!sock_flag(sk, SOCK_DEAD))
 421                         sk->sk_error_report(sk);
 422         }
 423
 424         return err;
 425 }
 426
 427 static int raw_getname(struct socket *sock, struct sockaddr *uaddr,
 428                        int *len, int peer)
 429 {
 430         struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
 431         struct sock *sk = sock->sk;
 432         struct raw_sock *ro = raw_sk(sk);
 433
 434         if (peer)
 435                 return -EOPNOTSUPP;
 436
 437         memset(addr, 0, sizeof(*addr));
 438         addr->can_family  = AF_CAN;
 439         addr->can_ifindex = ro->ifindex;
 440
 441         *len = sizeof(*addr);
 442
 443         return 0;
 444 }
 445
 446 static int raw_setsockopt(struct socket *sock, int level, int optname,
 447                           char __user *optval, unsigned int optlen)
 448 {
 449         struct sock *sk = sock->sk;
 450         struct raw_sock *ro = raw_sk(sk);
 451         struct can_filter *filter = NULL;  /* dyn. alloc'ed filters */
 452         struct can_filter sfilter;         /* single filter */
 453         struct net_device *dev = NULL;
 454         can_err_mask_t err_mask = 0;
 455         int count = 0;
 456         int err = 0;
 457
 458         if (level != SOL_CAN_RAW)
 459                 return -EINVAL;
 460
 461         switch (optname) {
 462
 463         case CAN_RAW_FILTER:
 464                 if (optlen % sizeof(struct can_filter) != 0)
 465                         return -EINVAL;
 466
 467                 count = optlen / sizeof(struct can_filter);
 468
 469                 if (count > 1) {
 470                         /* filter does not fit into dfilter => alloc space */
 471                         filter = memdup_user(optval, optlen);
 472                         if (IS_ERR(filter))
 473                                 return PTR_ERR(filter);
 474                 } else if (count == 1) {
 475                         if (copy_from_user(&sfilter, optval, sizeof(sfilter)))
 476                                 return -EFAULT;
 477                 }
 478
 479                 lock_sock(sk);
 480
 481                 if (ro->bound && ro->ifindex)
 482                         dev = dev_get_by_index(&init_net, ro->ifindex);
 483
 484                 if (ro->bound) {
 485                         /* (try to) register the new filters */
 486                         if (count == 1)
 487                                 err = raw_enable_filters(dev, sk, &sfilter, 1);
 488                         else
 489                                 err = raw_enable_filters(dev, sk, filter,
 490                                                          count);
 491                         if (err) {
 492                                 if (count > 1)
 493                                         kfree(filter);
 494                                 goto out_fil;
 495                         }
 496
 497                         /* remove old filter registrations */
 498                         raw_disable_filters(dev, sk, ro->filter, ro->count);
 499                 }
 500
 501                 /* remove old filter space */
 502                 if (ro->count > 1)
 503                         kfree(ro->filter);
 504
 505                 /* link new filters to the socket */
 506                 if (count == 1) {
 507                         /* copy filter data for single filter */
 508                         ro->dfilter = sfilter;
 509                         filter = &ro->dfilter;
 510                 }
 511                 ro->filter = filter;
 512                 ro->count  = count;
 513
 514  out_fil:
 515                 if (dev)
 516                         dev_put(dev);
 517
 518                 release_sock(sk);
 519
 520                 break;
 521
 522         case CAN_RAW_ERR_FILTER:
 523                 if (optlen != sizeof(err_mask))
 524                         return -EINVAL;
 525
 526                 if (copy_from_user(&err_mask, optval, optlen))
 527                         return -EFAULT;
 528
 529                 err_mask &= CAN_ERR_MASK;
 530
 531                 lock_sock(sk);
 532
 533                 if (ro->bound && ro->ifindex)
 534                         dev = dev_get_by_index(&init_net, ro->ifindex);
 535
 536                 /* remove current error mask */
 537                 if (ro->bound) {
 538                         /* (try to) register the new err_mask */
 539                         err = raw_enable_errfilter(dev, sk, err_mask);
 540
 541                         if (err)
 542                                 goto out_err;
 543
 544                         /* remove old err_mask registration */
 545                         raw_disable_errfilter(dev, sk, ro->err_mask);
 546                 }
 547
 548                 /* link new err_mask to the socket */
 549                 ro->err_mask = err_mask;
 550
 551  out_err:
 552                 if (dev)
 553                         dev_put(dev);
 554
 555                 release_sock(sk);
 556
 557                 break;
 558
 559         case CAN_RAW_LOOPBACK:
 560                 if (optlen != sizeof(ro->loopback))
 561                         return -EINVAL;
 562
 563                 if (copy_from_user(&ro->loopback, optval, optlen))
 564                         return -EFAULT;
 565
 566                 break;
 567
 568         case CAN_RAW_RECV_OWN_MSGS:
 569                 if (optlen != sizeof(ro->recv_own_msgs))
 570                         return -EINVAL;
 571
 572                 if (copy_from_user(&ro->recv_own_msgs, optval, optlen))
 573                         return -EFAULT;
 574
 575                 break;
 576
 577         case CAN_RAW_FD_FRAMES:
 578                 if (optlen != sizeof(ro->fd_frames))
 579                         return -EINVAL;
 580
 581                 if (copy_from_user(&ro->fd_frames, optval, optlen))
 582                         return -EFAULT;
 583
 584                 break;
 585
 586         default:
 587                 return -ENOPROTOOPT;
 588         }
 589         return err;
 590 }
 591
 592 static int raw_getsockopt(struct socket *sock, int level, int optname,
 593                           char __user *optval, int __user *optlen)
 594 {
 595         struct sock *sk = sock->sk;
 596         struct raw_sock *ro = raw_sk(sk);
 597         int len;
 598         void *val;
 599         int err = 0;
 600
 601         if (level != SOL_CAN_RAW)
 602                 return -EINVAL;
 603         if (get_user(len, optlen))
 604                 return -EFAULT;
 605         if (len < 0)
 606                 return -EINVAL;
 607
 608         switch (optname) {
 609
 610         case CAN_RAW_FILTER:
 611                 lock_sock(sk);
 612                 if (ro->count > 0) {
 613                         int fsize = ro->count * sizeof(struct can_filter);
 614                         if (len > fsize)
 615                                 len = fsize;
 616                         if (copy_to_user(optval, ro->filter, len))
 617                                 err = -EFAULT;
 618                 } else
 619                         len = 0;
 620                 release_sock(sk);
 621
 622                 if (!err)
 623                         err = put_user(len, optlen);
 624                 return err;
 625
 626         case CAN_RAW_ERR_FILTER:
 627                 if (len > sizeof(can_err_mask_t))
 628                         len = sizeof(can_err_mask_t);
 629                 val = &ro->err_mask;
 630                 break;
 631
 632         case CAN_RAW_LOOPBACK:
 633                 if (len > sizeof(int))
 634                         len = sizeof(int);
 635                 val = &ro->loopback;
 636                 break;
 637
 638         case CAN_RAW_RECV_OWN_MSGS:
 639                 if (len > sizeof(int))
 640                         len = sizeof(int);
 641                 val = &ro->recv_own_msgs;
 642                 break;
 643
 644         case CAN_RAW_FD_FRAMES:
 645                 if (len > sizeof(int))
 646                         len = sizeof(int);
 647                 val = &ro->fd_frames;
 648                 break;
 649
 650         default:
 651                 return -ENOPROTOOPT;
 652         }
 653
 654         if (put_user(len, optlen))
 655                 return -EFAULT;
 656         if (copy_to_user(optval, val, len))
 657                 return -EFAULT;
 658         return 0;
 659 }
 660
 661 static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
 662 {
 663         struct sock *sk = sock->sk;
 664         struct raw_sock *ro = raw_sk(sk);
 665         struct sk_buff *skb;
 666         struct net_device *dev;
 667         int ifindex;
 668         int err;
 669
 670         if (msg->msg_name) {
 671                 DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name);
 672
 673                 if (msg->msg_namelen < sizeof(*addr))
 674                         return -EINVAL;
 675
 676                 if (addr->can_family != AF_CAN)
 677                         return -EINVAL;
 678
 679                 ifindex = addr->can_ifindex;
 680         } else
 681                 ifindex = ro->ifindex;
 682
 683         if (ro->fd_frames) {
 684                 if (unlikely(size != CANFD_MTU && size != CAN_MTU))
 685                         return -EINVAL;
 686         } else {
 687                 if (unlikely(size != CAN_MTU))
 688                         return -EINVAL;
 689         }
 690
 691         dev = dev_get_by_index(&init_net, ifindex);
 692         if (!dev)
 693                 return -ENXIO;
 694
 695         skb = sock_alloc_send_skb(sk, size + sizeof(struct can_skb_priv),
 696                                   msg->msg_flags & MSG_DONTWAIT, &err);
 697         if (!skb)
 698                 goto put_dev;
 699
 700         can_skb_reserve(skb);
 701         can_skb_prv(skb)->ifindex = dev->ifindex;
 702
 703         err = memcpy_from_msg(skb_put(skb, size), msg, size);
 704         if (err < 0)
 705                 goto free_skb;
 706
 707         sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
 708
 709         skb->dev = dev;
 710         skb->sk  = sk;
 711         skb->priority = sk->sk_priority;
 712
 713         err = can_send(skb, ro->loopback);
 714
 715         dev_put(dev);
 716
 717         if (err)
 718                 goto send_failed;
 719
 720         return size;
 721
 722 free_skb:
 723         kfree_skb(skb);
 724 put_dev:
 725         dev_put(dev);
 726 send_failed:
 727         return err;
 728 }
 729
 730 static int raw_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
 731                        int flags)
 732 {
 733         struct sock *sk = sock->sk;
 734         struct sk_buff *skb;
 735         int err = 0;
 736         int noblock;
 737
 738         noblock =  flags & MSG_DONTWAIT;
 739         flags   &= ~MSG_DONTWAIT;
 740
 741         skb = skb_recv_datagram(sk, flags, noblock, &err);
 742         if (!skb)
 743                 return err;
 744
 745         if (size < skb->len)
 746                 msg->msg_flags |= MSG_TRUNC;
 747         else
 748                 size = skb->len;
 749
 750         err = memcpy_to_msg(msg, skb->data, size);
 751         if (err < 0) {
 752                 skb_free_datagram(sk, skb);
 753                 return err;
 754         }
 755
 756         sock_recv_ts_and_drops(msg, sk, skb);
 757
 758         if (msg->msg_name) {
 759                 __sockaddr_check_size(sizeof(struct sockaddr_can));
 760                 msg->msg_namelen = sizeof(struct sockaddr_can);
 761                 memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
 762         }
 763
 764         /* assign the flags that have been recorded in raw_rcv() */
 765         msg->msg_flags |= *(raw_flags(skb));
 766
 767         skb_free_datagram(sk, skb);
 768
 769         return size;
 770 }
 771
 772 static const struct proto_ops raw_ops = {
 773         .family        = PF_CAN,
 774         .release       = raw_release,
 775         .bind          = raw_bind,
 776         .connect       = sock_no_connect,
 777         .socketpair    = sock_no_socketpair,
 778         .accept        = sock_no_accept,
 779         .getname       = raw_getname,
 780         .poll          = datagram_poll,
 781         .ioctl         = can_ioctl,     /* use can_ioctl() from af_can.c */
 782         .listen        = sock_no_listen,
 783         .shutdown      = sock_no_shutdown,
 784         .setsockopt    = raw_setsockopt,
 785         .getsockopt    = raw_getsockopt,
 786         .sendmsg       = raw_sendmsg,
 787         .recvmsg       = raw_recvmsg,
 788         .mmap          = sock_no_mmap,
 789         .sendpage      = sock_no_sendpage,
 790 };
 791
 792 static struct proto raw_proto __read_mostly = {
 793         .name       = "CAN_RAW",
 794         .owner      = THIS_MODULE,
 795         .obj_size   = sizeof(struct raw_sock),
 796         .init       = raw_init,
 797 };
 798
 799 static const struct can_proto raw_can_proto = {
 800         .type       = SOCK_RAW,
 801         .protocol   = CAN_RAW,
 802         .ops        = &raw_ops,
 803         .prot       = &raw_proto,
 804 };
 805
 806 static __init int raw_module_init(void)
 807 {
 808         int err;
 809
 810         pr_info("can: raw protocol (rev " CAN_RAW_VERSION ")\n");
 811
 812         err = can_proto_register(&raw_can_proto);
 813         if (err < 0)
 814                 printk(KERN_ERR "can: registration of raw protocol failed\n");
 815
 816         return err;
 817 }
 818
 819 static __exit void raw_module_exit(void)
 820 {
 821         can_proto_unregister(&raw_can_proto);
 822 }
 823
 824 module_init(raw_module_init);
 825 module_exit(raw_module_exit);