1 // SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) 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 MODULE_DESCRIPTION("PF_CAN raw protocol"); 59 MODULE_LICENSE("Dual BSD/GPL"); 60 MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>"); 61 MODULE_ALIAS("can-proto-1"); 62 63 #define MASK_ALL 0 64 65 /* A raw socket has a list of can_filters attached to it, each receiving 66 * the CAN frames matching that filter. If the filter list is empty, 67 * no CAN frames will be received by the socket. The default after 68 * opening the socket, is to have one filter which receives all frames. 69 * The filter list is allocated dynamically with the exception of the 70 * list containing only one item. This common case is optimized by 71 * storing the single filter in dfilter, to avoid using dynamic memory. 72 */ 73 74 struct uniqframe { 75 int skbcnt; 76 const struct sk_buff *skb; 77 unsigned int join_rx_count; 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 fd_frames; 88 int join_filters; 89 int count; /* number of active filters */ 90 struct can_filter dfilter; /* default/single filter */ 91 struct can_filter *filter; /* pointer to filter(s) */ 92 can_err_mask_t err_mask; 93 struct uniqframe __percpu *uniq; 94 }; 95 96 /* Return pointer to store the extra msg flags for raw_recvmsg(). 97 * We use the space of one unsigned int beyond the 'struct sockaddr_can' 98 * in skb->cb. 99 */ 100 static inline unsigned int *raw_flags(struct sk_buff *skb) 101 { 102 sock_skb_cb_check_size(sizeof(struct sockaddr_can) + 103 sizeof(unsigned int)); 104 105 /* return pointer after struct sockaddr_can */ 106 return (unsigned int *)(&((struct sockaddr_can *)skb->cb)[1]); 107 } 108 109 static inline struct raw_sock *raw_sk(const struct sock *sk) 110 { 111 return (struct raw_sock *)sk; 112 } 113 114 static void raw_rcv(struct sk_buff *oskb, void *data) 115 { 116 struct sock *sk = (struct sock *)data; 117 struct raw_sock *ro = raw_sk(sk); 118 struct sockaddr_can *addr; 119 struct sk_buff *skb; 120 unsigned int *pflags; 121 122 /* check the received tx sock reference */ 123 if (!ro->recv_own_msgs && oskb->sk == sk) 124 return; 125 126 /* do not pass non-CAN2.0 frames to a legacy socket */ 127 if (!ro->fd_frames && oskb->len != CAN_MTU) 128 return; 129 130 /* eliminate multiple filter matches for the same skb */ 131 if (this_cpu_ptr(ro->uniq)->skb == oskb && 132 this_cpu_ptr(ro->uniq)->skbcnt == can_skb_prv(oskb)->skbcnt) { 133 if (ro->join_filters) { 134 this_cpu_inc(ro->uniq->join_rx_count); 135 /* drop frame until all enabled filters matched */ 136 if (this_cpu_ptr(ro->uniq)->join_rx_count < ro->count) 137 return; 138 } else { 139 return; 140 } 141 } else { 142 this_cpu_ptr(ro->uniq)->skb = oskb; 143 this_cpu_ptr(ro->uniq)->skbcnt = can_skb_prv(oskb)->skbcnt; 144 this_cpu_ptr(ro->uniq)->join_rx_count = 1; 145 /* drop first frame to check all enabled filters? */ 146 if (ro->join_filters && ro->count > 1) 147 return; 148 } 149 150 /* clone the given skb to be able to enqueue it into the rcv queue */ 151 skb = skb_clone(oskb, GFP_ATOMIC); 152 if (!skb) 153 return; 154 155 /* Put the datagram to the queue so that raw_recvmsg() can get 156 * it from there. We need to pass the interface index to 157 * raw_recvmsg(). We pass a whole struct sockaddr_can in 158 * skb->cb containing the interface index. 159 */ 160 161 sock_skb_cb_check_size(sizeof(struct sockaddr_can)); 162 addr = (struct sockaddr_can *)skb->cb; 163 memset(addr, 0, sizeof(*addr)); 164 addr->can_family = AF_CAN; 165 addr->can_ifindex = skb->dev->ifindex; 166 167 /* add CAN specific message flags for raw_recvmsg() */ 168 pflags = raw_flags(skb); 169 *pflags = 0; 170 if (oskb->sk) 171 *pflags |= MSG_DONTROUTE; 172 if (oskb->sk == sk) 173 *pflags |= MSG_CONFIRM; 174 175 if (sock_queue_rcv_skb(sk, skb) < 0) 176 kfree_skb(skb); 177 } 178 179 static int raw_enable_filters(struct net *net, struct net_device *dev, 180 struct sock *sk, struct can_filter *filter, 181 int count) 182 { 183 int err = 0; 184 int i; 185 186 for (i = 0; i < count; i++) { 187 err = can_rx_register(net, dev, filter[i].can_id, 188 filter[i].can_mask, 189 raw_rcv, sk, "raw", sk); 190 if (err) { 191 /* clean up successfully registered filters */ 192 while (--i >= 0) 193 can_rx_unregister(net, dev, filter[i].can_id, 194 filter[i].can_mask, 195 raw_rcv, sk); 196 break; 197 } 198 } 199 200 return err; 201 } 202 203 static int raw_enable_errfilter(struct net *net, struct net_device *dev, 204 struct sock *sk, can_err_mask_t err_mask) 205 { 206 int err = 0; 207 208 if (err_mask) 209 err = can_rx_register(net, dev, 0, err_mask | CAN_ERR_FLAG, 210 raw_rcv, sk, "raw", sk); 211 212 return err; 213 } 214 215 static void raw_disable_filters(struct net *net, struct net_device *dev, 216 struct sock *sk, struct can_filter *filter, 217 int count) 218 { 219 int i; 220 221 for (i = 0; i < count; i++) 222 can_rx_unregister(net, dev, filter[i].can_id, 223 filter[i].can_mask, raw_rcv, sk); 224 } 225 226 static inline void raw_disable_errfilter(struct net *net, 227 struct net_device *dev, 228 struct sock *sk, 229 can_err_mask_t err_mask) 230 231 { 232 if (err_mask) 233 can_rx_unregister(net, dev, 0, err_mask | CAN_ERR_FLAG, 234 raw_rcv, sk); 235 } 236 237 static inline void raw_disable_allfilters(struct net *net, 238 struct net_device *dev, 239 struct sock *sk) 240 { 241 struct raw_sock *ro = raw_sk(sk); 242 243 raw_disable_filters(net, dev, sk, ro->filter, ro->count); 244 raw_disable_errfilter(net, dev, sk, ro->err_mask); 245 } 246 247 static int raw_enable_allfilters(struct net *net, struct net_device *dev, 248 struct sock *sk) 249 { 250 struct raw_sock *ro = raw_sk(sk); 251 int err; 252 253 err = raw_enable_filters(net, dev, sk, ro->filter, ro->count); 254 if (!err) { 255 err = raw_enable_errfilter(net, dev, sk, ro->err_mask); 256 if (err) 257 raw_disable_filters(net, dev, sk, ro->filter, 258 ro->count); 259 } 260 261 return err; 262 } 263 264 static int raw_notifier(struct notifier_block *nb, 265 unsigned long msg, void *ptr) 266 { 267 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 268 struct raw_sock *ro = container_of(nb, struct raw_sock, notifier); 269 struct sock *sk = &ro->sk; 270 271 if (!net_eq(dev_net(dev), sock_net(sk))) 272 return NOTIFY_DONE; 273 274 if (dev->type != ARPHRD_CAN) 275 return NOTIFY_DONE; 276 277 if (ro->ifindex != dev->ifindex) 278 return NOTIFY_DONE; 279 280 switch (msg) { 281 case NETDEV_UNREGISTER: 282 lock_sock(sk); 283 /* remove current filters & unregister */ 284 if (ro->bound) 285 raw_disable_allfilters(dev_net(dev), 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(sock_net(sk), ro->ifindex); 362 if (dev) { 363 raw_disable_allfilters(dev_net(dev), dev, sk); 364 dev_put(dev); 365 } 366 } else { 367 raw_disable_allfilters(sock_net(sk), NULL, sk); 368 } 369 } 370 371 if (ro->count > 1) 372 kfree(ro->filter); 373 374 ro->ifindex = 0; 375 ro->bound = 0; 376 ro->count = 0; 377 free_percpu(ro->uniq); 378 379 sock_orphan(sk); 380 sock->sk = NULL; 381 382 release_sock(sk); 383 sock_put(sk); 384 385 return 0; 386 } 387 388 static int raw_bind(struct socket *sock, struct sockaddr *uaddr, int len) 389 { 390 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; 391 struct sock *sk = sock->sk; 392 struct raw_sock *ro = raw_sk(sk); 393 int ifindex; 394 int err = 0; 395 int notify_enetdown = 0; 396 397 if (len < CAN_REQUIRED_SIZE(*addr, can_ifindex)) 398 return -EINVAL; 399 if (addr->can_family != AF_CAN) 400 return -EINVAL; 401 402 lock_sock(sk); 403 404 if (ro->bound && addr->can_ifindex == ro->ifindex) 405 goto out; 406 407 if (addr->can_ifindex) { 408 struct net_device *dev; 409 410 dev = dev_get_by_index(sock_net(sk), addr->can_ifindex); 411 if (!dev) { 412 err = -ENODEV; 413 goto out; 414 } 415 if (dev->type != ARPHRD_CAN) { 416 dev_put(dev); 417 err = -ENODEV; 418 goto out; 419 } 420 if (!(dev->flags & IFF_UP)) 421 notify_enetdown = 1; 422 423 ifindex = dev->ifindex; 424 425 /* filters set by default/setsockopt */ 426 err = raw_enable_allfilters(sock_net(sk), dev, sk); 427 dev_put(dev); 428 } else { 429 ifindex = 0; 430 431 /* filters set by default/setsockopt */ 432 err = raw_enable_allfilters(sock_net(sk), NULL, sk); 433 } 434 435 if (!err) { 436 if (ro->bound) { 437 /* unregister old filters */ 438 if (ro->ifindex) { 439 struct net_device *dev; 440 441 dev = dev_get_by_index(sock_net(sk), 442 ro->ifindex); 443 if (dev) { 444 raw_disable_allfilters(dev_net(dev), 445 dev, sk); 446 dev_put(dev); 447 } 448 } else { 449 raw_disable_allfilters(sock_net(sk), NULL, sk); 450 } 451 } 452 ro->ifindex = ifindex; 453 ro->bound = 1; 454 } 455 456 out: 457 release_sock(sk); 458 459 if (notify_enetdown) { 460 sk->sk_err = ENETDOWN; 461 if (!sock_flag(sk, SOCK_DEAD)) 462 sk->sk_error_report(sk); 463 } 464 465 return err; 466 } 467 468 static int raw_getname(struct socket *sock, struct sockaddr *uaddr, 469 int peer) 470 { 471 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; 472 struct sock *sk = sock->sk; 473 struct raw_sock *ro = raw_sk(sk); 474 475 if (peer) 476 return -EOPNOTSUPP; 477 478 memset(addr, 0, sizeof(*addr)); 479 addr->can_family = AF_CAN; 480 addr->can_ifindex = ro->ifindex; 481 482 return sizeof(*addr); 483 } 484 485 static int raw_setsockopt(struct socket *sock, int level, int optname, 486 sockptr_t optval, unsigned int optlen) 487 { 488 struct sock *sk = sock->sk; 489 struct raw_sock *ro = raw_sk(sk); 490 struct can_filter *filter = NULL; /* dyn. alloc'ed filters */ 491 struct can_filter sfilter; /* single filter */ 492 struct net_device *dev = NULL; 493 can_err_mask_t err_mask = 0; 494 int count = 0; 495 int err = 0; 496 497 if (level != SOL_CAN_RAW) 498 return -EINVAL; 499 500 switch (optname) { 501 case CAN_RAW_FILTER: 502 if (optlen % sizeof(struct can_filter) != 0) 503 return -EINVAL; 504 505 if (optlen > CAN_RAW_FILTER_MAX * sizeof(struct can_filter)) 506 return -EINVAL; 507 508 count = optlen / sizeof(struct can_filter); 509 510 if (count > 1) { 511 /* filter does not fit into dfilter => alloc space */ 512 filter = memdup_sockptr(optval, optlen); 513 if (IS_ERR(filter)) 514 return PTR_ERR(filter); 515 } else if (count == 1) { 516 if (copy_from_sockptr(&sfilter, optval, sizeof(sfilter))) 517 return -EFAULT; 518 } 519 520 lock_sock(sk); 521 522 if (ro->bound && ro->ifindex) 523 dev = dev_get_by_index(sock_net(sk), ro->ifindex); 524 525 if (ro->bound) { 526 /* (try to) register the new filters */ 527 if (count == 1) 528 err = raw_enable_filters(sock_net(sk), dev, sk, 529 &sfilter, 1); 530 else 531 err = raw_enable_filters(sock_net(sk), dev, sk, 532 filter, count); 533 if (err) { 534 if (count > 1) 535 kfree(filter); 536 goto out_fil; 537 } 538 539 /* remove old filter registrations */ 540 raw_disable_filters(sock_net(sk), dev, sk, ro->filter, 541 ro->count); 542 } 543 544 /* remove old filter space */ 545 if (ro->count > 1) 546 kfree(ro->filter); 547 548 /* link new filters to the socket */ 549 if (count == 1) { 550 /* copy filter data for single filter */ 551 ro->dfilter = sfilter; 552 filter = &ro->dfilter; 553 } 554 ro->filter = filter; 555 ro->count = count; 556 557 out_fil: 558 if (dev) 559 dev_put(dev); 560 561 release_sock(sk); 562 563 break; 564 565 case CAN_RAW_ERR_FILTER: 566 if (optlen != sizeof(err_mask)) 567 return -EINVAL; 568 569 if (copy_from_sockptr(&err_mask, optval, optlen)) 570 return -EFAULT; 571 572 err_mask &= CAN_ERR_MASK; 573 574 lock_sock(sk); 575 576 if (ro->bound && ro->ifindex) 577 dev = dev_get_by_index(sock_net(sk), ro->ifindex); 578 579 /* remove current error mask */ 580 if (ro->bound) { 581 /* (try to) register the new err_mask */ 582 err = raw_enable_errfilter(sock_net(sk), dev, sk, 583 err_mask); 584 585 if (err) 586 goto out_err; 587 588 /* remove old err_mask registration */ 589 raw_disable_errfilter(sock_net(sk), dev, sk, 590 ro->err_mask); 591 } 592 593 /* link new err_mask to the socket */ 594 ro->err_mask = err_mask; 595 596 out_err: 597 if (dev) 598 dev_put(dev); 599 600 release_sock(sk); 601 602 break; 603 604 case CAN_RAW_LOOPBACK: 605 if (optlen != sizeof(ro->loopback)) 606 return -EINVAL; 607 608 if (copy_from_sockptr(&ro->loopback, optval, optlen)) 609 return -EFAULT; 610 611 break; 612 613 case CAN_RAW_RECV_OWN_MSGS: 614 if (optlen != sizeof(ro->recv_own_msgs)) 615 return -EINVAL; 616 617 if (copy_from_sockptr(&ro->recv_own_msgs, optval, optlen)) 618 return -EFAULT; 619 620 break; 621 622 case CAN_RAW_FD_FRAMES: 623 if (optlen != sizeof(ro->fd_frames)) 624 return -EINVAL; 625 626 if (copy_from_sockptr(&ro->fd_frames, optval, optlen)) 627 return -EFAULT; 628 629 break; 630 631 case CAN_RAW_JOIN_FILTERS: 632 if (optlen != sizeof(ro->join_filters)) 633 return -EINVAL; 634 635 if (copy_from_sockptr(&ro->join_filters, optval, optlen)) 636 return -EFAULT; 637 638 break; 639 640 default: 641 return -ENOPROTOOPT; 642 } 643 return err; 644 } 645 646 static int raw_getsockopt(struct socket *sock, int level, int optname, 647 char __user *optval, int __user *optlen) 648 { 649 struct sock *sk = sock->sk; 650 struct raw_sock *ro = raw_sk(sk); 651 int len; 652 void *val; 653 int err = 0; 654 655 if (level != SOL_CAN_RAW) 656 return -EINVAL; 657 if (get_user(len, optlen)) 658 return -EFAULT; 659 if (len < 0) 660 return -EINVAL; 661 662 switch (optname) { 663 case CAN_RAW_FILTER: 664 lock_sock(sk); 665 if (ro->count > 0) { 666 int fsize = ro->count * sizeof(struct can_filter); 667 668 /* user space buffer to small for filter list? */ 669 if (len < fsize) { 670 /* return -ERANGE and needed space in optlen */ 671 err = -ERANGE; 672 if (put_user(fsize, optlen)) 673 err = -EFAULT; 674 } else { 675 if (len > fsize) 676 len = fsize; 677 if (copy_to_user(optval, ro->filter, len)) 678 err = -EFAULT; 679 } 680 } else { 681 len = 0; 682 } 683 release_sock(sk); 684 685 if (!err) 686 err = put_user(len, optlen); 687 return err; 688 689 case CAN_RAW_ERR_FILTER: 690 if (len > sizeof(can_err_mask_t)) 691 len = sizeof(can_err_mask_t); 692 val = &ro->err_mask; 693 break; 694 695 case CAN_RAW_LOOPBACK: 696 if (len > sizeof(int)) 697 len = sizeof(int); 698 val = &ro->loopback; 699 break; 700 701 case CAN_RAW_RECV_OWN_MSGS: 702 if (len > sizeof(int)) 703 len = sizeof(int); 704 val = &ro->recv_own_msgs; 705 break; 706 707 case CAN_RAW_FD_FRAMES: 708 if (len > sizeof(int)) 709 len = sizeof(int); 710 val = &ro->fd_frames; 711 break; 712 713 case CAN_RAW_JOIN_FILTERS: 714 if (len > sizeof(int)) 715 len = sizeof(int); 716 val = &ro->join_filters; 717 break; 718 719 default: 720 return -ENOPROTOOPT; 721 } 722 723 if (put_user(len, optlen)) 724 return -EFAULT; 725 if (copy_to_user(optval, val, len)) 726 return -EFAULT; 727 return 0; 728 } 729 730 static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) 731 { 732 struct sock *sk = sock->sk; 733 struct raw_sock *ro = raw_sk(sk); 734 struct sk_buff *skb; 735 struct net_device *dev; 736 int ifindex; 737 int err; 738 739 if (msg->msg_name) { 740 DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name); 741 742 if (msg->msg_namelen < CAN_REQUIRED_SIZE(*addr, can_ifindex)) 743 return -EINVAL; 744 745 if (addr->can_family != AF_CAN) 746 return -EINVAL; 747 748 ifindex = addr->can_ifindex; 749 } else { 750 ifindex = ro->ifindex; 751 } 752 753 dev = dev_get_by_index(sock_net(sk), ifindex); 754 if (!dev) 755 return -ENXIO; 756 757 err = -EINVAL; 758 if (ro->fd_frames && dev->mtu == CANFD_MTU) { 759 if (unlikely(size != CANFD_MTU && size != CAN_MTU)) 760 goto put_dev; 761 } else { 762 if (unlikely(size != CAN_MTU)) 763 goto put_dev; 764 } 765 766 skb = sock_alloc_send_skb(sk, size + sizeof(struct can_skb_priv), 767 msg->msg_flags & MSG_DONTWAIT, &err); 768 if (!skb) 769 goto put_dev; 770 771 can_skb_reserve(skb); 772 can_skb_prv(skb)->ifindex = dev->ifindex; 773 can_skb_prv(skb)->skbcnt = 0; 774 775 err = memcpy_from_msg(skb_put(skb, size), msg, size); 776 if (err < 0) 777 goto free_skb; 778 779 skb_setup_tx_timestamp(skb, sk->sk_tsflags); 780 781 skb->dev = dev; 782 skb->sk = sk; 783 skb->priority = sk->sk_priority; 784 785 err = can_send(skb, ro->loopback); 786 787 dev_put(dev); 788 789 if (err) 790 goto send_failed; 791 792 return size; 793 794 free_skb: 795 kfree_skb(skb); 796 put_dev: 797 dev_put(dev); 798 send_failed: 799 return err; 800 } 801 802 static int raw_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 803 int flags) 804 { 805 struct sock *sk = sock->sk; 806 struct sk_buff *skb; 807 int err = 0; 808 int noblock; 809 810 noblock = flags & MSG_DONTWAIT; 811 flags &= ~MSG_DONTWAIT; 812 813 if (flags & MSG_ERRQUEUE) 814 return sock_recv_errqueue(sk, msg, size, 815 SOL_CAN_RAW, SCM_CAN_RAW_ERRQUEUE); 816 817 skb = skb_recv_datagram(sk, flags, noblock, &err); 818 if (!skb) 819 return err; 820 821 if (size < skb->len) 822 msg->msg_flags |= MSG_TRUNC; 823 else 824 size = skb->len; 825 826 err = memcpy_to_msg(msg, skb->data, size); 827 if (err < 0) { 828 skb_free_datagram(sk, skb); 829 return err; 830 } 831 832 sock_recv_ts_and_drops(msg, sk, skb); 833 834 if (msg->msg_name) { 835 __sockaddr_check_size(sizeof(struct sockaddr_can)); 836 msg->msg_namelen = sizeof(struct sockaddr_can); 837 memcpy(msg->msg_name, skb->cb, msg->msg_namelen); 838 } 839 840 /* assign the flags that have been recorded in raw_rcv() */ 841 msg->msg_flags |= *(raw_flags(skb)); 842 843 skb_free_datagram(sk, skb); 844 845 return size; 846 } 847 848 static int raw_sock_no_ioctlcmd(struct socket *sock, unsigned int cmd, 849 unsigned long arg) 850 { 851 /* no ioctls for socket layer -> hand it down to NIC layer */ 852 return -ENOIOCTLCMD; 853 } 854 855 static const struct proto_ops raw_ops = { 856 .family = PF_CAN, 857 .release = raw_release, 858 .bind = raw_bind, 859 .connect = sock_no_connect, 860 .socketpair = sock_no_socketpair, 861 .accept = sock_no_accept, 862 .getname = raw_getname, 863 .poll = datagram_poll, 864 .ioctl = raw_sock_no_ioctlcmd, 865 .gettstamp = sock_gettstamp, 866 .listen = sock_no_listen, 867 .shutdown = sock_no_shutdown, 868 .setsockopt = raw_setsockopt, 869 .getsockopt = raw_getsockopt, 870 .sendmsg = raw_sendmsg, 871 .recvmsg = raw_recvmsg, 872 .mmap = sock_no_mmap, 873 .sendpage = sock_no_sendpage, 874 }; 875 876 static struct proto raw_proto __read_mostly = { 877 .name = "CAN_RAW", 878 .owner = THIS_MODULE, 879 .obj_size = sizeof(struct raw_sock), 880 .init = raw_init, 881 }; 882 883 static const struct can_proto raw_can_proto = { 884 .type = SOCK_RAW, 885 .protocol = CAN_RAW, 886 .ops = &raw_ops, 887 .prot = &raw_proto, 888 }; 889 890 static __init int raw_module_init(void) 891 { 892 int err; 893 894 pr_info("can: raw protocol\n"); 895 896 err = can_proto_register(&raw_can_proto); 897 if (err < 0) 898 pr_err("can: registration of raw protocol failed\n"); 899 900 return err; 901 } 902 903 static __exit void raw_module_exit(void) 904 { 905 can_proto_unregister(&raw_can_proto); 906 } 907 908 module_init(raw_module_init); 909 module_exit(raw_module_exit); 910