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 uniqframe {
  78         int skbcnt;
  79         const struct sk_buff *skb;
  80         unsigned int join_rx_count;
  81 };
  82
  83 struct raw_sock {
  84         struct sock sk;
  85         int bound;
  86         int ifindex;
  87         struct notifier_block notifier;
  88         int loopback;
  89         int recv_own_msgs;
  90         int fd_frames;
  91         int join_filters;
  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;
  97 };
  98
  99 /*
 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'
 102  * in skb->cb.
 103  */
 104 static inline unsigned int *raw_flags(struct sk_buff *skb)
 105 {
 106         sock_skb_cb_check_size(sizeof(struct sockaddr_can) +
 107                                sizeof(unsigned int));
 108
 109         /* return pointer after struct sockaddr_can */
 110         return (unsigned int *)(&((struct sockaddr_can *)skb->cb)[1]);
 111 }
 112
 113 static inline struct raw_sock *raw_sk(const struct sock *sk)
 114 {
 115         return (struct raw_sock *)sk;
 116 }
 117
 118 static void raw_rcv(struct sk_buff *oskb, void *data)
 119 {
 120         struct sock *sk = (struct sock *)data;
 121         struct raw_sock *ro = raw_sk(sk);
 122         struct sockaddr_can *addr;
 123         struct sk_buff *skb;
 124         unsigned int *pflags;
 125
 126         /* check the received tx sock reference */
 127         if (!ro->recv_own_msgs && oskb->sk == sk)
 128                 return;
 129
 130         /* do not pass non-CAN2.0 frames to a legacy socket */
 131         if (!ro->fd_frames && oskb->len != CAN_MTU)
 132                 return;
 133
 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)
 141                                 return;
 142                 } else {
 143                         return;
 144                 }
 145         } else {
 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)
 151                         return;
 152         }
 153
 154         /* clone the given skb to be able to enqueue it into the rcv queue */
 155         skb = skb_clone(oskb, GFP_ATOMIC);
 156         if (!skb)
 157                 return;
 158
 159         /*
 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.
 164          */
 165
 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;
 171
 172         /* add CAN specific message flags for raw_recvmsg() */
 173         pflags = raw_flags(skb);
 174         *pflags = 0;
 175         if (oskb->sk)
 176                 *pflags |= MSG_DONTROUTE;
 177         if (oskb->sk == sk)
 178                 *pflags |= MSG_CONFIRM;
 179
 180         if (sock_queue_rcv_skb(sk, skb) < 0)
 181                 kfree_skb(skb);
 182 }
 183
 184 static int raw_enable_filters(struct net_device *dev, struct sock *sk,
 185                               struct can_filter *filter, int count)
 186 {
 187         int err = 0;
 188         int i;
 189
 190         for (i = 0; i < count; i++) {
 191                 err = can_rx_register(dev, filter[i].can_id,
 192                                       filter[i].can_mask,
 193                                       raw_rcv, sk, "raw");
 194                 if (err) {
 195                         /* clean up successfully registered filters */
 196                         while (--i >= 0)
 197                                 can_rx_unregister(dev, filter[i].can_id,
 198                                                   filter[i].can_mask,
 199                                                   raw_rcv, sk);
 200                         break;
 201                 }
 202         }
 203
 204         return err;
 205 }
 206
 207 static int raw_enable_errfilter(struct net_device *dev, struct sock *sk,
 208                                 can_err_mask_t err_mask)
 209 {
 210         int err = 0;
 211
 212         if (err_mask)
 213                 err = can_rx_register(dev, 0, err_mask | CAN_ERR_FLAG,
 214                                       raw_rcv, sk, "raw");
 215
 216         return err;
 217 }
 218
 219 static void raw_disable_filters(struct net_device *dev, struct sock *sk,
 220                               struct can_filter *filter, int count)
 221 {
 222         int i;
 223
 224         for (i = 0; i < count; i++)
 225                 can_rx_unregister(dev, filter[i].can_id, filter[i].can_mask,
 226                                   raw_rcv, sk);
 227 }
 228
 229 static inline void raw_disable_errfilter(struct net_device *dev,
 230                                          struct sock *sk,
 231                                          can_err_mask_t err_mask)
 232
 233 {
 234         if (err_mask)
 235                 can_rx_unregister(dev, 0, err_mask | CAN_ERR_FLAG,
 236                                   raw_rcv, sk);
 237 }
 238
 239 static inline void raw_disable_allfilters(struct net_device *dev,
 240                                           struct sock *sk)
 241 {
 242         struct raw_sock *ro = raw_sk(sk);
 243
 244         raw_disable_filters(dev, sk, ro->filter, ro->count);
 245         raw_disable_errfilter(dev, sk, ro->err_mask);
 246 }
 247
 248 static int raw_enable_allfilters(struct net_device *dev, struct sock *sk)
 249 {
 250         struct raw_sock *ro = raw_sk(sk);
 251         int err;
 252
 253         err = raw_enable_filters(dev, sk, ro->filter, ro->count);
 254         if (!err) {
 255                 err = raw_enable_errfilter(dev, sk, ro->err_mask);
 256                 if (err)
 257                         raw_disable_filters(dev, sk, ro->filter, ro->count);
 258         }
 259
 260         return err;
 261 }
 262
 263 static int raw_notifier(struct notifier_block *nb,
 264                         unsigned long msg, void *ptr)
 265 {
 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;
 269
 270         if (!net_eq(dev_net(dev), &init_net))
 271                 return NOTIFY_DONE;
 272
 273         if (dev->type != ARPHRD_CAN)
 274                 return NOTIFY_DONE;
 275
 276         if (ro->ifindex != dev->ifindex)
 277                 return NOTIFY_DONE;
 278
 279         switch (msg) {
 280
 281         case NETDEV_UNREGISTER:
 282                 lock_sock(sk);
 283                 /* remove current filters & unregister */
 284                 if (ro->bound)
 285                         raw_disable_allfilters(dev, sk);
 286
 287                 if (ro->count > 1)
 288                         kfree(ro->filter);
 289
 290                 ro->ifindex = 0;
 291                 ro->bound   = 0;
 292                 ro->count   = 0;
 293                 release_sock(sk);
 294
 295                 sk->sk_err = ENODEV;
 296                 if (!sock_flag(sk, SOCK_DEAD))
 297                         sk->sk_error_report(sk);
 298                 break;
 299
 300         case NETDEV_DOWN:
 301                 sk->sk_err = ENETDOWN;
 302                 if (!sock_flag(sk, SOCK_DEAD))
 303                         sk->sk_error_report(sk);
 304                 break;
 305         }
 306
 307         return NOTIFY_DONE;
 308 }
 309
 310 static int raw_init(struct sock *sk)
 311 {
 312         struct raw_sock *ro = raw_sk(sk);
 313
 314         ro->bound            = 0;
 315         ro->ifindex          = 0;
 316
 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;
 321         ro->count            = 1;
 322
 323         /* set default loopback behaviour */
 324         ro->loopback         = 1;
 325         ro->recv_own_msgs    = 0;
 326         ro->fd_frames        = 0;
 327         ro->join_filters     = 0;
 328
 329         /* alloc_percpu provides zero'ed memory */
 330         ro->uniq = alloc_percpu(struct uniqframe);
 331         if (unlikely(!ro->uniq))
 332                 return -ENOMEM;
 333
 334         /* set notifier */
 335         ro->notifier.notifier_call = raw_notifier;
 336
 337         register_netdevice_notifier(&ro->notifier);
 338
 339         return 0;
 340 }
 341
 342 static int raw_release(struct socket *sock)
 343 {
 344         struct sock *sk = sock->sk;
 345         struct raw_sock *ro;
 346
 347         if (!sk)
 348                 return 0;
 349
 350         ro = raw_sk(sk);
 351
 352         unregister_netdevice_notifier(&ro->notifier);
 353
 354         lock_sock(sk);
 355
 356         /* remove current filters & unregister */
 357         if (ro->bound) {
 358                 if (ro->ifindex) {
 359                         struct net_device *dev;
 360
 361                         dev = dev_get_by_index(&init_net, ro->ifindex);
 362                         if (dev) {
 363                                 raw_disable_allfilters(dev, sk);
 364                                 dev_put(dev);
 365                         }
 366                 } else
 367                         raw_disable_allfilters(NULL, sk);
 368         }
 369
 370         if (ro->count > 1)
 371                 kfree(ro->filter);
 372
 373         ro->ifindex = 0;
 374         ro->bound   = 0;
 375         ro->count   = 0;
 376         free_percpu(ro->uniq);
 377
 378         sock_orphan(sk);
 379         sock->sk = NULL;
 380
 381         release_sock(sk);
 382         sock_put(sk);
 383
 384         return 0;
 385 }
 386
 387 static int raw_bind(struct socket *sock, struct sockaddr *uaddr, int len)
 388 {
 389         struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
 390         struct sock *sk = sock->sk;
 391         struct raw_sock *ro = raw_sk(sk);
 392         int ifindex;
 393         int err = 0;
 394         int notify_enetdown = 0;
 395
 396         if (len < sizeof(*addr))
 397                 return -EINVAL;
 398
 399         lock_sock(sk);
 400
 401         if (ro->bound && addr->can_ifindex == ro->ifindex)
 402                 goto out;
 403
 404         if (addr->can_ifindex) {
 405                 struct net_device *dev;
 406
 407                 dev = dev_get_by_index(&init_net, addr->can_ifindex);
 408                 if (!dev) {
 409                         err = -ENODEV;
 410                         goto out;
 411                 }
 412                 if (dev->type != ARPHRD_CAN) {
 413                         dev_put(dev);
 414                         err = -ENODEV;
 415                         goto out;
 416                 }
 417                 if (!(dev->flags & IFF_UP))
 418                         notify_enetdown = 1;
 419
 420                 ifindex = dev->ifindex;
 421
 422                 /* filters set by default/setsockopt */
 423                 err = raw_enable_allfilters(dev, sk);
 424                 dev_put(dev);
 425         } else {
 426                 ifindex = 0;
 427
 428                 /* filters set by default/setsockopt */
 429                 err = raw_enable_allfilters(NULL, sk);
 430         }
 431
 432         if (!err) {
 433                 if (ro->bound) {
 434                         /* unregister old filters */
 435                         if (ro->ifindex) {
 436                                 struct net_device *dev;
 437
 438                                 dev = dev_get_by_index(&init_net, ro->ifindex);
 439                                 if (dev) {
 440                                         raw_disable_allfilters(dev, sk);
 441                                         dev_put(dev);
 442                                 }
 443                         } else
 444                                 raw_disable_allfilters(NULL, sk);
 445                 }
 446                 ro->ifindex = ifindex;
 447                 ro->bound = 1;
 448         }
 449
 450  out:
 451         release_sock(sk);
 452
 453         if (notify_enetdown) {
 454                 sk->sk_err = ENETDOWN;
 455                 if (!sock_flag(sk, SOCK_DEAD))
 456                         sk->sk_error_report(sk);
 457         }
 458
 459         return err;
 460 }
 461
 462 static int raw_getname(struct socket *sock, struct sockaddr *uaddr,
 463                        int *len, int peer)
 464 {
 465         struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
 466         struct sock *sk = sock->sk;
 467         struct raw_sock *ro = raw_sk(sk);
 468
 469         if (peer)
 470                 return -EOPNOTSUPP;
 471
 472         memset(addr, 0, sizeof(*addr));
 473         addr->can_family  = AF_CAN;
 474         addr->can_ifindex = ro->ifindex;
 475
 476         *len = sizeof(*addr);
 477
 478         return 0;
 479 }
 480
 481 static int raw_setsockopt(struct socket *sock, int level, int optname,
 482                           char __user *optval, unsigned int optlen)
 483 {
 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;
 490         int count = 0;
 491         int err = 0;
 492
 493         if (level != SOL_CAN_RAW)
 494                 return -EINVAL;
 495
 496         switch (optname) {
 497
 498         case CAN_RAW_FILTER:
 499                 if (optlen % sizeof(struct can_filter) != 0)
 500                         return -EINVAL;
 501
 502                 if (optlen > CAN_RAW_FILTER_MAX * sizeof(struct can_filter))
 503                         return -EINVAL;
 504
 505                 count = optlen / sizeof(struct can_filter);
 506
 507                 if (count > 1) {
 508                         /* filter does not fit into dfilter => alloc space */
 509                         filter = memdup_user(optval, optlen);
 510                         if (IS_ERR(filter))
 511                                 return PTR_ERR(filter);
 512                 } else if (count == 1) {
 513                         if (copy_from_user(&sfilter, optval, sizeof(sfilter)))
 514                                 return -EFAULT;
 515                 }
 516
 517                 lock_sock(sk);
 518
 519                 if (ro->bound && ro->ifindex)
 520                         dev = dev_get_by_index(&init_net, ro->ifindex);
 521
 522                 if (ro->bound) {
 523                         /* (try to) register the new filters */
 524                         if (count == 1)
 525                                 err = raw_enable_filters(dev, sk, &sfilter, 1);
 526                         else
 527                                 err = raw_enable_filters(dev, sk, filter,
 528                                                          count);
 529                         if (err) {
 530                                 if (count > 1)
 531                                         kfree(filter);
 532                                 goto out_fil;
 533                         }
 534
 535                         /* remove old filter registrations */
 536                         raw_disable_filters(dev, sk, ro->filter, ro->count);
 537                 }
 538
 539                 /* remove old filter space */
 540                 if (ro->count > 1)
 541                         kfree(ro->filter);
 542
 543                 /* link new filters to the socket */
 544                 if (count == 1) {
 545                         /* copy filter data for single filter */
 546                         ro->dfilter = sfilter;
 547                         filter = &ro->dfilter;
 548                 }
 549                 ro->filter = filter;
 550                 ro->count  = count;
 551
 552  out_fil:
 553                 if (dev)
 554                         dev_put(dev);
 555
 556                 release_sock(sk);
 557
 558                 break;
 559
 560         case CAN_RAW_ERR_FILTER:
 561                 if (optlen != sizeof(err_mask))
 562                         return -EINVAL;
 563
 564                 if (copy_from_user(&err_mask, optval, optlen))
 565                         return -EFAULT;
 566
 567                 err_mask &= CAN_ERR_MASK;
 568
 569                 lock_sock(sk);
 570
 571                 if (ro->bound && ro->ifindex)
 572                         dev = dev_get_by_index(&init_net, ro->ifindex);
 573
 574                 /* remove current error mask */
 575                 if (ro->bound) {
 576                         /* (try to) register the new err_mask */
 577                         err = raw_enable_errfilter(dev, sk, err_mask);
 578
 579                         if (err)
 580                                 goto out_err;
 581
 582                         /* remove old err_mask registration */
 583                         raw_disable_errfilter(dev, sk, ro->err_mask);
 584                 }
 585
 586                 /* link new err_mask to the socket */
 587                 ro->err_mask = err_mask;
 588
 589  out_err:
 590                 if (dev)
 591                         dev_put(dev);
 592
 593                 release_sock(sk);
 594
 595                 break;
 596
 597         case CAN_RAW_LOOPBACK:
 598                 if (optlen != sizeof(ro->loopback))
 599                         return -EINVAL;
 600
 601                 if (copy_from_user(&ro->loopback, optval, optlen))
 602                         return -EFAULT;
 603
 604                 break;
 605
 606         case CAN_RAW_RECV_OWN_MSGS:
 607                 if (optlen != sizeof(ro->recv_own_msgs))
 608                         return -EINVAL;
 609
 610                 if (copy_from_user(&ro->recv_own_msgs, optval, optlen))
 611                         return -EFAULT;
 612
 613                 break;
 614
 615         case CAN_RAW_FD_FRAMES:
 616                 if (optlen != sizeof(ro->fd_frames))
 617                         return -EINVAL;
 618
 619                 if (copy_from_user(&ro->fd_frames, optval, optlen))
 620                         return -EFAULT;
 621
 622                 break;
 623
 624         case CAN_RAW_JOIN_FILTERS:
 625                 if (optlen != sizeof(ro->join_filters))
 626                         return -EINVAL;
 627
 628                 if (copy_from_user(&ro->join_filters, optval, optlen))
 629                         return -EFAULT;
 630
 631                 break;
 632
 633         default:
 634                 return -ENOPROTOOPT;
 635         }
 636         return err;
 637 }
 638
 639 static int raw_getsockopt(struct socket *sock, int level, int optname,
 640                           char __user *optval, int __user *optlen)
 641 {
 642         struct sock *sk = sock->sk;
 643         struct raw_sock *ro = raw_sk(sk);
 644         int len;
 645         void *val;
 646         int err = 0;
 647
 648         if (level != SOL_CAN_RAW)
 649                 return -EINVAL;
 650         if (get_user(len, optlen))
 651                 return -EFAULT;
 652         if (len < 0)
 653                 return -EINVAL;
 654
 655         switch (optname) {
 656
 657         case CAN_RAW_FILTER:
 658                 lock_sock(sk);
 659                 if (ro->count > 0) {
 660                         int fsize = ro->count * sizeof(struct can_filter);
 661                         if (len > fsize)
 662                                 len = fsize;
 663                         if (copy_to_user(optval, ro->filter, len))
 664                                 err = -EFAULT;
 665                 } else
 666                         len = 0;
 667                 release_sock(sk);
 668
 669                 if (!err)
 670                         err = put_user(len, optlen);
 671                 return err;
 672
 673         case CAN_RAW_ERR_FILTER:
 674                 if (len > sizeof(can_err_mask_t))
 675                         len = sizeof(can_err_mask_t);
 676                 val = &ro->err_mask;
 677                 break;
 678
 679         case CAN_RAW_LOOPBACK:
 680                 if (len > sizeof(int))
 681                         len = sizeof(int);
 682                 val = &ro->loopback;
 683                 break;
 684
 685         case CAN_RAW_RECV_OWN_MSGS:
 686                 if (len > sizeof(int))
 687                         len = sizeof(int);
 688                 val = &ro->recv_own_msgs;
 689                 break;
 690
 691         case CAN_RAW_FD_FRAMES:
 692                 if (len > sizeof(int))
 693                         len = sizeof(int);
 694                 val = &ro->fd_frames;
 695                 break;
 696
 697         case CAN_RAW_JOIN_FILTERS:
 698                 if (len > sizeof(int))
 699                         len = sizeof(int);
 700                 val = &ro->join_filters;
 701                 break;
 702
 703         default:
 704                 return -ENOPROTOOPT;
 705         }
 706
 707         if (put_user(len, optlen))
 708                 return -EFAULT;
 709         if (copy_to_user(optval, val, len))
 710                 return -EFAULT;
 711         return 0;
 712 }
 713
 714 static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
 715 {
 716         struct sock *sk = sock->sk;
 717         struct raw_sock *ro = raw_sk(sk);
 718         struct sk_buff *skb;
 719         struct net_device *dev;
 720         int ifindex;
 721         int err;
 722
 723         if (msg->msg_name) {
 724                 DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name);
 725
 726                 if (msg->msg_namelen < sizeof(*addr))
 727                         return -EINVAL;
 728
 729                 if (addr->can_family != AF_CAN)
 730                         return -EINVAL;
 731
 732                 ifindex = addr->can_ifindex;
 733         } else
 734                 ifindex = ro->ifindex;
 735
 736         if (ro->fd_frames) {
 737                 if (unlikely(size != CANFD_MTU && size != CAN_MTU))
 738                         return -EINVAL;
 739         } else {
 740                 if (unlikely(size != CAN_MTU))
 741                         return -EINVAL;
 742         }
 743
 744         dev = dev_get_by_index(&init_net, ifindex);
 745         if (!dev)
 746                 return -ENXIO;
 747
 748         skb = sock_alloc_send_skb(sk, size + sizeof(struct can_skb_priv),
 749                                   msg->msg_flags & MSG_DONTWAIT, &err);
 750         if (!skb)
 751                 goto put_dev;
 752
 753         can_skb_reserve(skb);
 754         can_skb_prv(skb)->ifindex = dev->ifindex;
 755         can_skb_prv(skb)->skbcnt = 0;
 756
 757         err = memcpy_from_msg(skb_put(skb, size), msg, size);
 758         if (err < 0)
 759                 goto free_skb;
 760
 761         sock_tx_timestamp(sk, sk->sk_tsflags, &skb_shinfo(skb)->tx_flags);
 762
 763         skb->dev = dev;
 764         skb->sk  = sk;
 765         skb->priority = sk->sk_priority;
 766
 767         err = can_send(skb, ro->loopback);
 768
 769         dev_put(dev);
 770
 771         if (err)
 772                 goto send_failed;
 773
 774         return size;
 775
 776 free_skb:
 777         kfree_skb(skb);
 778 put_dev:
 779         dev_put(dev);
 780 send_failed:
 781         return err;
 782 }
 783
 784 static int raw_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
 785                        int flags)
 786 {
 787         struct sock *sk = sock->sk;
 788         struct sk_buff *skb;
 789         int err = 0;
 790         int noblock;
 791
 792         noblock =  flags & MSG_DONTWAIT;
 793         flags   &= ~MSG_DONTWAIT;
 794
 795         skb = skb_recv_datagram(sk, flags, noblock, &err);
 796         if (!skb)
 797                 return err;
 798
 799         if (size < skb->len)
 800                 msg->msg_flags |= MSG_TRUNC;
 801         else
 802                 size = skb->len;
 803
 804         err = memcpy_to_msg(msg, skb->data, size);
 805         if (err < 0) {
 806                 skb_free_datagram(sk, skb);
 807                 return err;
 808         }
 809
 810         sock_recv_ts_and_drops(msg, sk, skb);
 811
 812         if (msg->msg_name) {
 813                 __sockaddr_check_size(sizeof(struct sockaddr_can));
 814                 msg->msg_namelen = sizeof(struct sockaddr_can);
 815                 memcpy(msg->msg_name, skb->cb, msg->msg_namelen);
 816         }
 817
 818         /* assign the flags that have been recorded in raw_rcv() */
 819         msg->msg_flags |= *(raw_flags(skb));
 820
 821         skb_free_datagram(sk, skb);
 822
 823         return size;
 824 }
 825
 826 static const struct proto_ops raw_ops = {
 827         .family        = PF_CAN,
 828         .release       = raw_release,
 829         .bind          = raw_bind,
 830         .connect       = sock_no_connect,
 831         .socketpair    = sock_no_socketpair,
 832         .accept        = sock_no_accept,
 833         .getname       = raw_getname,
 834         .poll          = datagram_poll,
 835         .ioctl         = can_ioctl,     /* use can_ioctl() from af_can.c */
 836         .listen        = sock_no_listen,
 837         .shutdown      = sock_no_shutdown,
 838         .setsockopt    = raw_setsockopt,
 839         .getsockopt    = raw_getsockopt,
 840         .sendmsg       = raw_sendmsg,
 841         .recvmsg       = raw_recvmsg,
 842         .mmap          = sock_no_mmap,
 843         .sendpage      = sock_no_sendpage,
 844 };
 845
 846 static struct proto raw_proto __read_mostly = {
 847         .name       = "CAN_RAW",
 848         .owner      = THIS_MODULE,
 849         .obj_size   = sizeof(struct raw_sock),
 850         .init       = raw_init,
 851 };
 852
 853 static const struct can_proto raw_can_proto = {
 854         .type       = SOCK_RAW,
 855         .protocol   = CAN_RAW,
 856         .ops        = &raw_ops,
 857         .prot       = &raw_proto,
 858 };
 859
 860 static __init int raw_module_init(void)
 861 {
 862         int err;
 863
 864         pr_info("can: raw protocol (rev " CAN_RAW_VERSION ")\n");
 865
 866         err = can_proto_register(&raw_can_proto);
 867         if (err < 0)
 868                 printk(KERN_ERR "can: registration of raw protocol failed\n");
 869
 870         return err;
 871 }
 872
 873 static __exit void raw_module_exit(void)
 874 {
 875         can_proto_unregister(&raw_can_proto);
 876 }
 877
 878 module_init(raw_module_init);
 879 module_exit(raw_module_exit);