1 // SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 2 /* 3 * raw.c - Raw sockets for protocol family CAN 4 * 5 * Copyright (c) 2002-2007 Volkswagen Group Electronic Research 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of Volkswagen nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * Alternatively, provided that this notice is retained in full, this 21 * software may be distributed under the terms of the GNU General 22 * Public License ("GPL") version 2, in which case the provisions of the 23 * GPL apply INSTEAD OF those given above. 24 * 25 * The provided data structures and external interfaces from this code 26 * are not restricted to be used by modules with a GPL compatible license. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 29 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 30 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 31 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 32 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 33 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 34 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 35 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 36 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 37 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 38 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH 39 * DAMAGE. 40 * 41 */ 42 43 #include <linux/module.h> 44 #include <linux/init.h> 45 #include <linux/uio.h> 46 #include <linux/net.h> 47 #include <linux/slab.h> 48 #include <linux/netdevice.h> 49 #include <linux/socket.h> 50 #include <linux/if_arp.h> 51 #include <linux/skbuff.h> 52 #include <linux/can.h> 53 #include <linux/can/core.h> 54 #include <linux/can/skb.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 61 MODULE_DESCRIPTION("PF_CAN raw protocol"); 62 MODULE_LICENSE("Dual BSD/GPL"); 63 MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>"); 64 MODULE_ALIAS("can-proto-1"); 65 66 #define MASK_ALL 0 67 68 /* 69 * A raw socket has a list of can_filters attached to it, each receiving 70 * the CAN frames matching that filter. If the filter list is empty, 71 * no CAN frames will be received by the socket. The default after 72 * opening the socket, is to have one filter which receives all frames. 73 * The filter list is allocated dynamically with the exception of the 74 * list containing only one item. This common case is optimized by 75 * storing the single filter in dfilter, to avoid using dynamic memory. 76 */ 77 78 struct uniqframe { 79 int skbcnt; 80 const struct sk_buff *skb; 81 unsigned int join_rx_count; 82 }; 83 84 struct raw_sock { 85 struct sock sk; 86 int bound; 87 int ifindex; 88 struct notifier_block notifier; 89 int loopback; 90 int recv_own_msgs; 91 int fd_frames; 92 int join_filters; 93 int count; /* number of active filters */ 94 struct can_filter dfilter; /* default/single filter */ 95 struct can_filter *filter; /* pointer to filter(s) */ 96 can_err_mask_t err_mask; 97 struct uniqframe __percpu *uniq; 98 }; 99 100 /* 101 * Return pointer to store the extra msg flags for raw_recvmsg(). 102 * We use the space of one unsigned int beyond the 'struct sockaddr_can' 103 * in skb->cb. 104 */ 105 static inline unsigned int *raw_flags(struct sk_buff *skb) 106 { 107 sock_skb_cb_check_size(sizeof(struct sockaddr_can) + 108 sizeof(unsigned int)); 109 110 /* return pointer after struct sockaddr_can */ 111 return (unsigned int *)(&((struct sockaddr_can *)skb->cb)[1]); 112 } 113 114 static inline struct raw_sock *raw_sk(const struct sock *sk) 115 { 116 return (struct raw_sock *)sk; 117 } 118 119 static void raw_rcv(struct sk_buff *oskb, void *data) 120 { 121 struct sock *sk = (struct sock *)data; 122 struct raw_sock *ro = raw_sk(sk); 123 struct sockaddr_can *addr; 124 struct sk_buff *skb; 125 unsigned int *pflags; 126 127 /* check the received tx sock reference */ 128 if (!ro->recv_own_msgs && oskb->sk == sk) 129 return; 130 131 /* do not pass non-CAN2.0 frames to a legacy socket */ 132 if (!ro->fd_frames && oskb->len != CAN_MTU) 133 return; 134 135 /* eliminate multiple filter matches for the same skb */ 136 if (this_cpu_ptr(ro->uniq)->skb == oskb && 137 this_cpu_ptr(ro->uniq)->skbcnt == can_skb_prv(oskb)->skbcnt) { 138 if (ro->join_filters) { 139 this_cpu_inc(ro->uniq->join_rx_count); 140 /* drop frame until all enabled filters matched */ 141 if (this_cpu_ptr(ro->uniq)->join_rx_count < ro->count) 142 return; 143 } else { 144 return; 145 } 146 } else { 147 this_cpu_ptr(ro->uniq)->skb = oskb; 148 this_cpu_ptr(ro->uniq)->skbcnt = can_skb_prv(oskb)->skbcnt; 149 this_cpu_ptr(ro->uniq)->join_rx_count = 1; 150 /* drop first frame to check all enabled filters? */ 151 if (ro->join_filters && ro->count > 1) 152 return; 153 } 154 155 /* clone the given skb to be able to enqueue it into the rcv queue */ 156 skb = skb_clone(oskb, GFP_ATOMIC); 157 if (!skb) 158 return; 159 160 /* 161 * Put the datagram to the queue so that raw_recvmsg() can 162 * get it from there. We need to pass the interface index to 163 * raw_recvmsg(). We pass a whole struct sockaddr_can in skb->cb 164 * containing the interface index. 165 */ 166 167 sock_skb_cb_check_size(sizeof(struct sockaddr_can)); 168 addr = (struct sockaddr_can *)skb->cb; 169 memset(addr, 0, sizeof(*addr)); 170 addr->can_family = AF_CAN; 171 addr->can_ifindex = skb->dev->ifindex; 172 173 /* add CAN specific message flags for raw_recvmsg() */ 174 pflags = raw_flags(skb); 175 *pflags = 0; 176 if (oskb->sk) 177 *pflags |= MSG_DONTROUTE; 178 if (oskb->sk == sk) 179 *pflags |= MSG_CONFIRM; 180 181 if (sock_queue_rcv_skb(sk, skb) < 0) 182 kfree_skb(skb); 183 } 184 185 static int raw_enable_filters(struct net *net, struct net_device *dev, 186 struct sock *sk, struct can_filter *filter, 187 int count) 188 { 189 int err = 0; 190 int i; 191 192 for (i = 0; i < count; i++) { 193 err = can_rx_register(net, dev, filter[i].can_id, 194 filter[i].can_mask, 195 raw_rcv, sk, "raw", sk); 196 if (err) { 197 /* clean up successfully registered filters */ 198 while (--i >= 0) 199 can_rx_unregister(net, dev, filter[i].can_id, 200 filter[i].can_mask, 201 raw_rcv, sk); 202 break; 203 } 204 } 205 206 return err; 207 } 208 209 static int raw_enable_errfilter(struct net *net, struct net_device *dev, 210 struct sock *sk, can_err_mask_t err_mask) 211 { 212 int err = 0; 213 214 if (err_mask) 215 err = can_rx_register(net, dev, 0, err_mask | CAN_ERR_FLAG, 216 raw_rcv, sk, "raw", sk); 217 218 return err; 219 } 220 221 static void raw_disable_filters(struct net *net, struct net_device *dev, 222 struct sock *sk, struct can_filter *filter, 223 int count) 224 { 225 int i; 226 227 for (i = 0; i < count; i++) 228 can_rx_unregister(net, dev, filter[i].can_id, 229 filter[i].can_mask, raw_rcv, sk); 230 } 231 232 static inline void raw_disable_errfilter(struct net *net, 233 struct net_device *dev, 234 struct sock *sk, 235 can_err_mask_t err_mask) 236 237 { 238 if (err_mask) 239 can_rx_unregister(net, dev, 0, err_mask | CAN_ERR_FLAG, 240 raw_rcv, sk); 241 } 242 243 static inline void raw_disable_allfilters(struct net *net, 244 struct net_device *dev, 245 struct sock *sk) 246 { 247 struct raw_sock *ro = raw_sk(sk); 248 249 raw_disable_filters(net, dev, sk, ro->filter, ro->count); 250 raw_disable_errfilter(net, dev, sk, ro->err_mask); 251 } 252 253 static int raw_enable_allfilters(struct net *net, struct net_device *dev, 254 struct sock *sk) 255 { 256 struct raw_sock *ro = raw_sk(sk); 257 int err; 258 259 err = raw_enable_filters(net, dev, sk, ro->filter, ro->count); 260 if (!err) { 261 err = raw_enable_errfilter(net, dev, sk, ro->err_mask); 262 if (err) 263 raw_disable_filters(net, dev, sk, ro->filter, 264 ro->count); 265 } 266 267 return err; 268 } 269 270 static int raw_notifier(struct notifier_block *nb, 271 unsigned long msg, void *ptr) 272 { 273 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 274 struct raw_sock *ro = container_of(nb, struct raw_sock, notifier); 275 struct sock *sk = &ro->sk; 276 277 if (!net_eq(dev_net(dev), sock_net(sk))) 278 return NOTIFY_DONE; 279 280 if (dev->type != ARPHRD_CAN) 281 return NOTIFY_DONE; 282 283 if (ro->ifindex != dev->ifindex) 284 return NOTIFY_DONE; 285 286 switch (msg) { 287 288 case NETDEV_UNREGISTER: 289 lock_sock(sk); 290 /* remove current filters & unregister */ 291 if (ro->bound) 292 raw_disable_allfilters(dev_net(dev), dev, sk); 293 294 if (ro->count > 1) 295 kfree(ro->filter); 296 297 ro->ifindex = 0; 298 ro->bound = 0; 299 ro->count = 0; 300 release_sock(sk); 301 302 sk->sk_err = ENODEV; 303 if (!sock_flag(sk, SOCK_DEAD)) 304 sk->sk_error_report(sk); 305 break; 306 307 case NETDEV_DOWN: 308 sk->sk_err = ENETDOWN; 309 if (!sock_flag(sk, SOCK_DEAD)) 310 sk->sk_error_report(sk); 311 break; 312 } 313 314 return NOTIFY_DONE; 315 } 316 317 static int raw_init(struct sock *sk) 318 { 319 struct raw_sock *ro = raw_sk(sk); 320 321 ro->bound = 0; 322 ro->ifindex = 0; 323 324 /* set default filter to single entry dfilter */ 325 ro->dfilter.can_id = 0; 326 ro->dfilter.can_mask = MASK_ALL; 327 ro->filter = &ro->dfilter; 328 ro->count = 1; 329 330 /* set default loopback behaviour */ 331 ro->loopback = 1; 332 ro->recv_own_msgs = 0; 333 ro->fd_frames = 0; 334 ro->join_filters = 0; 335 336 /* alloc_percpu provides zero'ed memory */ 337 ro->uniq = alloc_percpu(struct uniqframe); 338 if (unlikely(!ro->uniq)) 339 return -ENOMEM; 340 341 /* set notifier */ 342 ro->notifier.notifier_call = raw_notifier; 343 344 register_netdevice_notifier(&ro->notifier); 345 346 return 0; 347 } 348 349 static int raw_release(struct socket *sock) 350 { 351 struct sock *sk = sock->sk; 352 struct raw_sock *ro; 353 354 if (!sk) 355 return 0; 356 357 ro = raw_sk(sk); 358 359 unregister_netdevice_notifier(&ro->notifier); 360 361 lock_sock(sk); 362 363 /* remove current filters & unregister */ 364 if (ro->bound) { 365 if (ro->ifindex) { 366 struct net_device *dev; 367 368 dev = dev_get_by_index(sock_net(sk), ro->ifindex); 369 if (dev) { 370 raw_disable_allfilters(dev_net(dev), dev, sk); 371 dev_put(dev); 372 } 373 } else 374 raw_disable_allfilters(sock_net(sk), NULL, sk); 375 } 376 377 if (ro->count > 1) 378 kfree(ro->filter); 379 380 ro->ifindex = 0; 381 ro->bound = 0; 382 ro->count = 0; 383 free_percpu(ro->uniq); 384 385 sock_orphan(sk); 386 sock->sk = NULL; 387 388 release_sock(sk); 389 sock_put(sk); 390 391 return 0; 392 } 393 394 static int raw_bind(struct socket *sock, struct sockaddr *uaddr, int len) 395 { 396 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; 397 struct sock *sk = sock->sk; 398 struct raw_sock *ro = raw_sk(sk); 399 int ifindex; 400 int err = 0; 401 int notify_enetdown = 0; 402 403 if (len < sizeof(*addr)) 404 return -EINVAL; 405 if (addr->can_family != AF_CAN) 406 return -EINVAL; 407 408 lock_sock(sk); 409 410 if (ro->bound && addr->can_ifindex == ro->ifindex) 411 goto out; 412 413 if (addr->can_ifindex) { 414 struct net_device *dev; 415 416 dev = dev_get_by_index(sock_net(sk), addr->can_ifindex); 417 if (!dev) { 418 err = -ENODEV; 419 goto out; 420 } 421 if (dev->type != ARPHRD_CAN) { 422 dev_put(dev); 423 err = -ENODEV; 424 goto out; 425 } 426 if (!(dev->flags & IFF_UP)) 427 notify_enetdown = 1; 428 429 ifindex = dev->ifindex; 430 431 /* filters set by default/setsockopt */ 432 err = raw_enable_allfilters(sock_net(sk), dev, sk); 433 dev_put(dev); 434 } else { 435 ifindex = 0; 436 437 /* filters set by default/setsockopt */ 438 err = raw_enable_allfilters(sock_net(sk), NULL, sk); 439 } 440 441 if (!err) { 442 if (ro->bound) { 443 /* unregister old filters */ 444 if (ro->ifindex) { 445 struct net_device *dev; 446 447 dev = dev_get_by_index(sock_net(sk), 448 ro->ifindex); 449 if (dev) { 450 raw_disable_allfilters(dev_net(dev), 451 dev, sk); 452 dev_put(dev); 453 } 454 } else 455 raw_disable_allfilters(sock_net(sk), NULL, sk); 456 } 457 ro->ifindex = ifindex; 458 ro->bound = 1; 459 } 460 461 out: 462 release_sock(sk); 463 464 if (notify_enetdown) { 465 sk->sk_err = ENETDOWN; 466 if (!sock_flag(sk, SOCK_DEAD)) 467 sk->sk_error_report(sk); 468 } 469 470 return err; 471 } 472 473 static int raw_getname(struct socket *sock, struct sockaddr *uaddr, 474 int peer) 475 { 476 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; 477 struct sock *sk = sock->sk; 478 struct raw_sock *ro = raw_sk(sk); 479 480 if (peer) 481 return -EOPNOTSUPP; 482 483 memset(addr, 0, sizeof(*addr)); 484 addr->can_family = AF_CAN; 485 addr->can_ifindex = ro->ifindex; 486 487 return sizeof(*addr); 488 } 489 490 static int raw_setsockopt(struct socket *sock, int level, int optname, 491 char __user *optval, unsigned int optlen) 492 { 493 struct sock *sk = sock->sk; 494 struct raw_sock *ro = raw_sk(sk); 495 struct can_filter *filter = NULL; /* dyn. alloc'ed filters */ 496 struct can_filter sfilter; /* single filter */ 497 struct net_device *dev = NULL; 498 can_err_mask_t err_mask = 0; 499 int count = 0; 500 int err = 0; 501 502 if (level != SOL_CAN_RAW) 503 return -EINVAL; 504 505 switch (optname) { 506 507 case CAN_RAW_FILTER: 508 if (optlen % sizeof(struct can_filter) != 0) 509 return -EINVAL; 510 511 if (optlen > CAN_RAW_FILTER_MAX * sizeof(struct can_filter)) 512 return -EINVAL; 513 514 count = optlen / sizeof(struct can_filter); 515 516 if (count > 1) { 517 /* filter does not fit into dfilter => alloc space */ 518 filter = memdup_user(optval, optlen); 519 if (IS_ERR(filter)) 520 return PTR_ERR(filter); 521 } else if (count == 1) { 522 if (copy_from_user(&sfilter, optval, sizeof(sfilter))) 523 return -EFAULT; 524 } 525 526 lock_sock(sk); 527 528 if (ro->bound && ro->ifindex) 529 dev = dev_get_by_index(sock_net(sk), ro->ifindex); 530 531 if (ro->bound) { 532 /* (try to) register the new filters */ 533 if (count == 1) 534 err = raw_enable_filters(sock_net(sk), dev, sk, 535 &sfilter, 1); 536 else 537 err = raw_enable_filters(sock_net(sk), dev, sk, 538 filter, count); 539 if (err) { 540 if (count > 1) 541 kfree(filter); 542 goto out_fil; 543 } 544 545 /* remove old filter registrations */ 546 raw_disable_filters(sock_net(sk), dev, sk, ro->filter, 547 ro->count); 548 } 549 550 /* remove old filter space */ 551 if (ro->count > 1) 552 kfree(ro->filter); 553 554 /* link new filters to the socket */ 555 if (count == 1) { 556 /* copy filter data for single filter */ 557 ro->dfilter = sfilter; 558 filter = &ro->dfilter; 559 } 560 ro->filter = filter; 561 ro->count = count; 562 563 out_fil: 564 if (dev) 565 dev_put(dev); 566 567 release_sock(sk); 568 569 break; 570 571 case CAN_RAW_ERR_FILTER: 572 if (optlen != sizeof(err_mask)) 573 return -EINVAL; 574 575 if (copy_from_user(&err_mask, optval, optlen)) 576 return -EFAULT; 577 578 err_mask &= CAN_ERR_MASK; 579 580 lock_sock(sk); 581 582 if (ro->bound && ro->ifindex) 583 dev = dev_get_by_index(sock_net(sk), ro->ifindex); 584 585 /* remove current error mask */ 586 if (ro->bound) { 587 /* (try to) register the new err_mask */ 588 err = raw_enable_errfilter(sock_net(sk), dev, sk, 589 err_mask); 590 591 if (err) 592 goto out_err; 593 594 /* remove old err_mask registration */ 595 raw_disable_errfilter(sock_net(sk), dev, sk, 596 ro->err_mask); 597 } 598 599 /* link new err_mask to the socket */ 600 ro->err_mask = err_mask; 601 602 out_err: 603 if (dev) 604 dev_put(dev); 605 606 release_sock(sk); 607 608 break; 609 610 case CAN_RAW_LOOPBACK: 611 if (optlen != sizeof(ro->loopback)) 612 return -EINVAL; 613 614 if (copy_from_user(&ro->loopback, optval, optlen)) 615 return -EFAULT; 616 617 break; 618 619 case CAN_RAW_RECV_OWN_MSGS: 620 if (optlen != sizeof(ro->recv_own_msgs)) 621 return -EINVAL; 622 623 if (copy_from_user(&ro->recv_own_msgs, optval, optlen)) 624 return -EFAULT; 625 626 break; 627 628 case CAN_RAW_FD_FRAMES: 629 if (optlen != sizeof(ro->fd_frames)) 630 return -EINVAL; 631 632 if (copy_from_user(&ro->fd_frames, optval, optlen)) 633 return -EFAULT; 634 635 break; 636 637 case CAN_RAW_JOIN_FILTERS: 638 if (optlen != sizeof(ro->join_filters)) 639 return -EINVAL; 640 641 if (copy_from_user(&ro->join_filters, optval, optlen)) 642 return -EFAULT; 643 644 break; 645 646 default: 647 return -ENOPROTOOPT; 648 } 649 return err; 650 } 651 652 static int raw_getsockopt(struct socket *sock, int level, int optname, 653 char __user *optval, int __user *optlen) 654 { 655 struct sock *sk = sock->sk; 656 struct raw_sock *ro = raw_sk(sk); 657 int len; 658 void *val; 659 int err = 0; 660 661 if (level != SOL_CAN_RAW) 662 return -EINVAL; 663 if (get_user(len, optlen)) 664 return -EFAULT; 665 if (len < 0) 666 return -EINVAL; 667 668 switch (optname) { 669 670 case CAN_RAW_FILTER: 671 lock_sock(sk); 672 if (ro->count > 0) { 673 int fsize = ro->count * sizeof(struct can_filter); 674 if (len > fsize) 675 len = fsize; 676 if (copy_to_user(optval, ro->filter, len)) 677 err = -EFAULT; 678 } else 679 len = 0; 680 release_sock(sk); 681 682 if (!err) 683 err = put_user(len, optlen); 684 return err; 685 686 case CAN_RAW_ERR_FILTER: 687 if (len > sizeof(can_err_mask_t)) 688 len = sizeof(can_err_mask_t); 689 val = &ro->err_mask; 690 break; 691 692 case CAN_RAW_LOOPBACK: 693 if (len > sizeof(int)) 694 len = sizeof(int); 695 val = &ro->loopback; 696 break; 697 698 case CAN_RAW_RECV_OWN_MSGS: 699 if (len > sizeof(int)) 700 len = sizeof(int); 701 val = &ro->recv_own_msgs; 702 break; 703 704 case CAN_RAW_FD_FRAMES: 705 if (len > sizeof(int)) 706 len = sizeof(int); 707 val = &ro->fd_frames; 708 break; 709 710 case CAN_RAW_JOIN_FILTERS: 711 if (len > sizeof(int)) 712 len = sizeof(int); 713 val = &ro->join_filters; 714 break; 715 716 default: 717 return -ENOPROTOOPT; 718 } 719 720 if (put_user(len, optlen)) 721 return -EFAULT; 722 if (copy_to_user(optval, val, len)) 723 return -EFAULT; 724 return 0; 725 } 726 727 static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) 728 { 729 struct sock *sk = sock->sk; 730 struct raw_sock *ro = raw_sk(sk); 731 struct sk_buff *skb; 732 struct net_device *dev; 733 int ifindex; 734 int err; 735 736 if (msg->msg_name) { 737 DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name); 738 739 if (msg->msg_namelen < sizeof(*addr)) 740 return -EINVAL; 741 742 if (addr->can_family != AF_CAN) 743 return -EINVAL; 744 745 ifindex = addr->can_ifindex; 746 } else 747 ifindex = ro->ifindex; 748 749 dev = dev_get_by_index(sock_net(sk), ifindex); 750 if (!dev) 751 return -ENXIO; 752 753 err = -EINVAL; 754 if (ro->fd_frames && dev->mtu == CANFD_MTU) { 755 if (unlikely(size != CANFD_MTU && size != CAN_MTU)) 756 goto put_dev; 757 } else { 758 if (unlikely(size != CAN_MTU)) 759 goto put_dev; 760 } 761 762 skb = sock_alloc_send_skb(sk, size + sizeof(struct can_skb_priv), 763 msg->msg_flags & MSG_DONTWAIT, &err); 764 if (!skb) 765 goto put_dev; 766 767 can_skb_reserve(skb); 768 can_skb_prv(skb)->ifindex = dev->ifindex; 769 can_skb_prv(skb)->skbcnt = 0; 770 771 err = memcpy_from_msg(skb_put(skb, size), msg, size); 772 if (err < 0) 773 goto free_skb; 774 775 skb_setup_tx_timestamp(skb, sk->sk_tsflags); 776 777 skb->dev = dev; 778 skb->sk = sk; 779 skb->priority = sk->sk_priority; 780 781 err = can_send(skb, ro->loopback); 782 783 dev_put(dev); 784 785 if (err) 786 goto send_failed; 787 788 return size; 789 790 free_skb: 791 kfree_skb(skb); 792 put_dev: 793 dev_put(dev); 794 send_failed: 795 return err; 796 } 797 798 static int raw_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 799 int flags) 800 { 801 struct sock *sk = sock->sk; 802 struct sk_buff *skb; 803 int err = 0; 804 int noblock; 805 806 noblock = flags & MSG_DONTWAIT; 807 flags &= ~MSG_DONTWAIT; 808 809 skb = skb_recv_datagram(sk, flags, noblock, &err); 810 if (!skb) 811 return err; 812 813 if (size < skb->len) 814 msg->msg_flags |= MSG_TRUNC; 815 else 816 size = skb->len; 817 818 err = memcpy_to_msg(msg, skb->data, size); 819 if (err < 0) { 820 skb_free_datagram(sk, skb); 821 return err; 822 } 823 824 sock_recv_ts_and_drops(msg, sk, skb); 825 826 if (msg->msg_name) { 827 __sockaddr_check_size(sizeof(struct sockaddr_can)); 828 msg->msg_namelen = sizeof(struct sockaddr_can); 829 memcpy(msg->msg_name, skb->cb, msg->msg_namelen); 830 } 831 832 /* assign the flags that have been recorded in raw_rcv() */ 833 msg->msg_flags |= *(raw_flags(skb)); 834 835 skb_free_datagram(sk, skb); 836 837 return size; 838 } 839 840 int raw_sock_no_ioctlcmd(struct socket *sock, unsigned int cmd, 841 unsigned long arg) 842 { 843 /* no ioctls for socket layer -> hand it down to NIC layer */ 844 return -ENOIOCTLCMD; 845 } 846 847 static const struct proto_ops raw_ops = { 848 .family = PF_CAN, 849 .release = raw_release, 850 .bind = raw_bind, 851 .connect = sock_no_connect, 852 .socketpair = sock_no_socketpair, 853 .accept = sock_no_accept, 854 .getname = raw_getname, 855 .poll = datagram_poll, 856 .ioctl = raw_sock_no_ioctlcmd, 857 .gettstamp = sock_gettstamp, 858 .listen = sock_no_listen, 859 .shutdown = sock_no_shutdown, 860 .setsockopt = raw_setsockopt, 861 .getsockopt = raw_getsockopt, 862 .sendmsg = raw_sendmsg, 863 .recvmsg = raw_recvmsg, 864 .mmap = sock_no_mmap, 865 .sendpage = sock_no_sendpage, 866 }; 867 868 static struct proto raw_proto __read_mostly = { 869 .name = "CAN_RAW", 870 .owner = THIS_MODULE, 871 .obj_size = sizeof(struct raw_sock), 872 .init = raw_init, 873 }; 874 875 static const struct can_proto raw_can_proto = { 876 .type = SOCK_RAW, 877 .protocol = CAN_RAW, 878 .ops = &raw_ops, 879 .prot = &raw_proto, 880 }; 881 882 static __init int raw_module_init(void) 883 { 884 int err; 885 886 pr_info("can: raw protocol (rev " CAN_RAW_VERSION ")\n"); 887 888 err = can_proto_register(&raw_can_proto); 889 if (err < 0) 890 printk(KERN_ERR "can: registration of raw protocol failed\n"); 891 892 return err; 893 } 894 895 static __exit void raw_module_exit(void) 896 { 897 can_proto_unregister(&raw_can_proto); 898 } 899 900 module_init(raw_module_init); 901 module_exit(raw_module_exit); 902