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