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/can-ml.h> 53 #include <linux/can/core.h> 54 #include <linux/can/skb.h> 55 #include <linux/can/raw.h> 56 #include <net/can.h> 57 #include <net/sock.h> 58 #include <net/net_namespace.h> 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 RAW_MIN_NAMELEN CAN_REQUIRED_SIZE(struct sockaddr_can, can_ifindex) 66 67 #define MASK_ALL 0 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 const struct sk_buff *skb; 80 u32 hash; 81 unsigned int join_rx_count; 82 }; 83 84 struct raw_sock { 85 struct sock sk; 86 struct net_device *dev; 87 netdevice_tracker dev_tracker; 88 struct list_head notifier; 89 int ifindex; 90 unsigned int bound:1; 91 unsigned int loopback:1; 92 unsigned int recv_own_msgs:1; 93 unsigned int fd_frames:1; 94 unsigned int xl_frames:1; 95 unsigned int join_filters:1; 96 struct can_raw_vcid_options raw_vcid_opts; 97 canid_t tx_vcid_shifted; 98 canid_t rx_vcid_shifted; 99 canid_t rx_vcid_mask_shifted; 100 can_err_mask_t err_mask; 101 int count; /* number of active filters */ 102 struct can_filter dfilter; /* default/single filter */ 103 struct can_filter *filter; /* pointer to filter(s) */ 104 struct uniqframe __percpu *uniq; 105 }; 106 107 static LIST_HEAD(raw_notifier_list); 108 static DEFINE_SPINLOCK(raw_notifier_lock); 109 static struct raw_sock *raw_busy_notifier; 110 111 /* Return pointer to store the extra msg flags for raw_recvmsg(). 112 * We use the space of one unsigned int beyond the 'struct sockaddr_can' 113 * in skb->cb. 114 */ 115 static inline unsigned int *raw_flags(struct sk_buff *skb) 116 { 117 sock_skb_cb_check_size(sizeof(struct sockaddr_can) + 118 sizeof(unsigned int)); 119 120 /* return pointer after struct sockaddr_can */ 121 return (unsigned int *)(&((struct sockaddr_can *)skb->cb)[1]); 122 } 123 124 static inline struct raw_sock *raw_sk(const struct sock *sk) 125 { 126 return (struct raw_sock *)sk; 127 } 128 129 static void raw_rcv(struct sk_buff *oskb, void *data) 130 { 131 struct sock *sk = (struct sock *)data; 132 struct raw_sock *ro = raw_sk(sk); 133 enum skb_drop_reason reason; 134 struct sockaddr_can *addr; 135 struct sk_buff *skb; 136 unsigned int *pflags; 137 138 /* check the received tx sock reference */ 139 if (!ro->recv_own_msgs && oskb->sk == sk) 140 return; 141 142 /* make sure to not pass oversized frames to the socket */ 143 if (!ro->fd_frames && can_is_canfd_skb(oskb)) 144 return; 145 146 if (can_is_canxl_skb(oskb)) { 147 struct canxl_frame *cxl = (struct canxl_frame *)oskb->data; 148 149 /* make sure to not pass oversized frames to the socket */ 150 if (!ro->xl_frames) 151 return; 152 153 /* filter CAN XL VCID content */ 154 if (ro->raw_vcid_opts.flags & CAN_RAW_XL_VCID_RX_FILTER) { 155 /* apply VCID filter if user enabled the filter */ 156 if ((cxl->prio & ro->rx_vcid_mask_shifted) != 157 (ro->rx_vcid_shifted & ro->rx_vcid_mask_shifted)) 158 return; 159 } else { 160 /* no filter => do not forward VCID tagged frames */ 161 if (cxl->prio & CANXL_VCID_MASK) 162 return; 163 } 164 } 165 166 /* eliminate multiple filter matches for the same skb */ 167 if (this_cpu_ptr(ro->uniq)->skb == oskb && 168 this_cpu_ptr(ro->uniq)->hash == oskb->hash) { 169 if (!ro->join_filters) 170 return; 171 172 this_cpu_inc(ro->uniq->join_rx_count); 173 /* drop frame until all enabled filters matched */ 174 if (this_cpu_ptr(ro->uniq)->join_rx_count < ro->count) 175 return; 176 } else { 177 this_cpu_ptr(ro->uniq)->skb = oskb; 178 this_cpu_ptr(ro->uniq)->hash = oskb->hash; 179 this_cpu_ptr(ro->uniq)->join_rx_count = 1; 180 /* drop first frame to check all enabled filters? */ 181 if (ro->join_filters && ro->count > 1) 182 return; 183 } 184 185 /* clone the given skb to be able to enqueue it into the rcv queue */ 186 skb = skb_clone(oskb, GFP_ATOMIC); 187 if (!skb) 188 return; 189 190 /* Put the datagram to the queue so that raw_recvmsg() can get 191 * it from there. We need to pass the interface index to 192 * raw_recvmsg(). We pass a whole struct sockaddr_can in 193 * skb->cb containing the interface index. 194 */ 195 196 sock_skb_cb_check_size(sizeof(struct sockaddr_can)); 197 addr = (struct sockaddr_can *)skb->cb; 198 memset(addr, 0, sizeof(*addr)); 199 addr->can_family = AF_CAN; 200 addr->can_ifindex = skb->dev->ifindex; 201 202 /* add CAN specific message flags for raw_recvmsg() */ 203 pflags = raw_flags(skb); 204 *pflags = 0; 205 if (oskb->sk) 206 *pflags |= MSG_DONTROUTE; 207 if (oskb->sk == sk) 208 *pflags |= MSG_CONFIRM; 209 210 reason = sock_queue_rcv_skb_reason(sk, skb); 211 if (reason) 212 sk_skb_reason_drop(sk, skb, reason); 213 } 214 215 static int raw_enable_filters(struct net *net, struct net_device *dev, 216 struct sock *sk, struct can_filter *filter, 217 int count) 218 { 219 int err = 0; 220 int i; 221 222 for (i = 0; i < count; i++) { 223 err = can_rx_register(net, dev, filter[i].can_id, 224 filter[i].can_mask, 225 raw_rcv, sk, "raw", sk); 226 if (err) { 227 /* clean up successfully registered filters */ 228 while (--i >= 0) 229 can_rx_unregister(net, dev, filter[i].can_id, 230 filter[i].can_mask, 231 raw_rcv, sk); 232 break; 233 } 234 } 235 236 return err; 237 } 238 239 static int raw_enable_errfilter(struct net *net, struct net_device *dev, 240 struct sock *sk, can_err_mask_t err_mask) 241 { 242 int err = 0; 243 244 if (err_mask) 245 err = can_rx_register(net, dev, 0, err_mask | CAN_ERR_FLAG, 246 raw_rcv, sk, "raw", sk); 247 248 return err; 249 } 250 251 static void raw_disable_filters(struct net *net, struct net_device *dev, 252 struct sock *sk, struct can_filter *filter, 253 int count) 254 { 255 int i; 256 257 for (i = 0; i < count; i++) 258 can_rx_unregister(net, dev, filter[i].can_id, 259 filter[i].can_mask, raw_rcv, sk); 260 } 261 262 static inline void raw_disable_errfilter(struct net *net, 263 struct net_device *dev, 264 struct sock *sk, 265 can_err_mask_t err_mask) 266 267 { 268 if (err_mask) 269 can_rx_unregister(net, dev, 0, err_mask | CAN_ERR_FLAG, 270 raw_rcv, sk); 271 } 272 273 static inline void raw_disable_allfilters(struct net *net, 274 struct net_device *dev, 275 struct sock *sk) 276 { 277 struct raw_sock *ro = raw_sk(sk); 278 279 raw_disable_filters(net, dev, sk, ro->filter, ro->count); 280 raw_disable_errfilter(net, dev, sk, ro->err_mask); 281 } 282 283 static int raw_enable_allfilters(struct net *net, struct net_device *dev, 284 struct sock *sk) 285 { 286 struct raw_sock *ro = raw_sk(sk); 287 int err; 288 289 err = raw_enable_filters(net, dev, sk, ro->filter, ro->count); 290 if (!err) { 291 err = raw_enable_errfilter(net, dev, sk, ro->err_mask); 292 if (err) 293 raw_disable_filters(net, dev, sk, ro->filter, 294 ro->count); 295 } 296 297 return err; 298 } 299 300 static void raw_notify(struct raw_sock *ro, unsigned long msg, 301 struct net_device *dev) 302 { 303 struct sock *sk = &ro->sk; 304 305 if (!net_eq(dev_net(dev), sock_net(sk))) 306 return; 307 308 if (ro->dev != dev) 309 return; 310 311 switch (msg) { 312 case NETDEV_UNREGISTER: 313 lock_sock(sk); 314 /* remove current filters & unregister */ 315 if (ro->bound) { 316 raw_disable_allfilters(dev_net(dev), dev, sk); 317 netdev_put(dev, &ro->dev_tracker); 318 } 319 320 if (ro->count > 1) 321 kfree(ro->filter); 322 323 ro->ifindex = 0; 324 ro->bound = 0; 325 ro->dev = NULL; 326 ro->count = 0; 327 release_sock(sk); 328 329 sk->sk_err = ENODEV; 330 if (!sock_flag(sk, SOCK_DEAD)) 331 sk_error_report(sk); 332 break; 333 334 case NETDEV_DOWN: 335 sk->sk_err = ENETDOWN; 336 if (!sock_flag(sk, SOCK_DEAD)) 337 sk_error_report(sk); 338 break; 339 } 340 } 341 342 static int raw_notifier(struct notifier_block *nb, unsigned long msg, 343 void *ptr) 344 { 345 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 346 347 if (dev->type != ARPHRD_CAN) 348 return NOTIFY_DONE; 349 if (msg != NETDEV_UNREGISTER && msg != NETDEV_DOWN) 350 return NOTIFY_DONE; 351 if (unlikely(raw_busy_notifier)) /* Check for reentrant bug. */ 352 return NOTIFY_DONE; 353 354 spin_lock(&raw_notifier_lock); 355 list_for_each_entry(raw_busy_notifier, &raw_notifier_list, notifier) { 356 spin_unlock(&raw_notifier_lock); 357 raw_notify(raw_busy_notifier, msg, dev); 358 spin_lock(&raw_notifier_lock); 359 } 360 raw_busy_notifier = NULL; 361 spin_unlock(&raw_notifier_lock); 362 return NOTIFY_DONE; 363 } 364 365 static int raw_init(struct sock *sk) 366 { 367 struct raw_sock *ro = raw_sk(sk); 368 369 ro->bound = 0; 370 ro->ifindex = 0; 371 ro->dev = NULL; 372 373 /* set default filter to single entry dfilter */ 374 ro->dfilter.can_id = 0; 375 ro->dfilter.can_mask = MASK_ALL; 376 ro->filter = &ro->dfilter; 377 ro->count = 1; 378 379 /* set default loopback behaviour */ 380 ro->loopback = 1; 381 ro->recv_own_msgs = 0; 382 ro->fd_frames = 0; 383 ro->xl_frames = 0; 384 ro->join_filters = 0; 385 386 /* alloc_percpu provides zero'ed memory */ 387 ro->uniq = alloc_percpu(struct uniqframe); 388 if (unlikely(!ro->uniq)) 389 return -ENOMEM; 390 391 /* set notifier */ 392 spin_lock(&raw_notifier_lock); 393 list_add_tail(&ro->notifier, &raw_notifier_list); 394 spin_unlock(&raw_notifier_lock); 395 396 return 0; 397 } 398 399 static int raw_release(struct socket *sock) 400 { 401 struct sock *sk = sock->sk; 402 struct raw_sock *ro; 403 struct net *net; 404 405 if (!sk) 406 return 0; 407 408 ro = raw_sk(sk); 409 net = sock_net(sk); 410 411 spin_lock(&raw_notifier_lock); 412 while (raw_busy_notifier == ro) { 413 spin_unlock(&raw_notifier_lock); 414 schedule_timeout_uninterruptible(1); 415 spin_lock(&raw_notifier_lock); 416 } 417 list_del(&ro->notifier); 418 spin_unlock(&raw_notifier_lock); 419 420 rtnl_lock(); 421 lock_sock(sk); 422 423 /* remove current filters & unregister */ 424 if (ro->bound) { 425 if (ro->dev) { 426 raw_disable_allfilters(dev_net(ro->dev), ro->dev, sk); 427 netdev_put(ro->dev, &ro->dev_tracker); 428 } else { 429 raw_disable_allfilters(net, NULL, sk); 430 } 431 } 432 433 if (ro->count > 1) 434 kfree(ro->filter); 435 436 ro->ifindex = 0; 437 ro->bound = 0; 438 ro->dev = NULL; 439 ro->count = 0; 440 free_percpu(ro->uniq); 441 442 sock_orphan(sk); 443 sock->sk = NULL; 444 445 release_sock(sk); 446 rtnl_unlock(); 447 448 sock_prot_inuse_add(net, sk->sk_prot, -1); 449 sock_put(sk); 450 451 return 0; 452 } 453 454 static int raw_bind(struct socket *sock, struct sockaddr_unsized *uaddr, int len) 455 { 456 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; 457 struct sock *sk = sock->sk; 458 struct raw_sock *ro = raw_sk(sk); 459 struct net_device *dev = NULL; 460 int ifindex; 461 int err = 0; 462 int notify_enetdown = 0; 463 464 if (len < RAW_MIN_NAMELEN) 465 return -EINVAL; 466 if (addr->can_family != AF_CAN) 467 return -EINVAL; 468 469 rtnl_lock(); 470 lock_sock(sk); 471 472 if (ro->bound && addr->can_ifindex == ro->ifindex) 473 goto out; 474 475 if (addr->can_ifindex) { 476 dev = dev_get_by_index(sock_net(sk), addr->can_ifindex); 477 if (!dev) { 478 err = -ENODEV; 479 goto out; 480 } 481 if (dev->type != ARPHRD_CAN) { 482 err = -ENODEV; 483 goto out_put_dev; 484 } 485 486 if (!(dev->flags & IFF_UP)) 487 notify_enetdown = 1; 488 489 ifindex = dev->ifindex; 490 491 /* filters set by default/setsockopt */ 492 err = raw_enable_allfilters(sock_net(sk), dev, sk); 493 if (err) 494 goto out_put_dev; 495 496 } else { 497 ifindex = 0; 498 499 /* filters set by default/setsockopt */ 500 err = raw_enable_allfilters(sock_net(sk), NULL, sk); 501 } 502 503 if (!err) { 504 if (ro->bound) { 505 /* unregister old filters */ 506 if (ro->dev) { 507 raw_disable_allfilters(dev_net(ro->dev), 508 ro->dev, sk); 509 /* drop reference to old ro->dev */ 510 netdev_put(ro->dev, &ro->dev_tracker); 511 } else { 512 raw_disable_allfilters(sock_net(sk), NULL, sk); 513 } 514 } 515 ro->ifindex = ifindex; 516 ro->bound = 1; 517 /* bind() ok -> hold a reference for new ro->dev */ 518 ro->dev = dev; 519 if (ro->dev) 520 netdev_hold(ro->dev, &ro->dev_tracker, GFP_KERNEL); 521 } 522 523 out_put_dev: 524 /* remove potential reference from dev_get_by_index() */ 525 dev_put(dev); 526 out: 527 release_sock(sk); 528 rtnl_unlock(); 529 530 if (notify_enetdown) { 531 sk->sk_err = ENETDOWN; 532 if (!sock_flag(sk, SOCK_DEAD)) 533 sk_error_report(sk); 534 } 535 536 return err; 537 } 538 539 static int raw_getname(struct socket *sock, struct sockaddr *uaddr, 540 int peer) 541 { 542 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; 543 struct sock *sk = sock->sk; 544 struct raw_sock *ro = raw_sk(sk); 545 546 if (peer) 547 return -EOPNOTSUPP; 548 549 memset(addr, 0, RAW_MIN_NAMELEN); 550 addr->can_family = AF_CAN; 551 addr->can_ifindex = ro->ifindex; 552 553 return RAW_MIN_NAMELEN; 554 } 555 556 static int raw_setsockopt(struct socket *sock, int level, int optname, 557 sockptr_t optval, unsigned int optlen) 558 { 559 struct sock *sk = sock->sk; 560 struct raw_sock *ro = raw_sk(sk); 561 struct can_filter *filter = NULL; /* dyn. alloc'ed filters */ 562 struct can_filter sfilter; /* single filter */ 563 struct net_device *dev = NULL; 564 can_err_mask_t err_mask = 0; 565 int count = 0; 566 int flag; 567 int err = 0; 568 569 if (level != SOL_CAN_RAW) 570 return -EINVAL; 571 572 switch (optname) { 573 case CAN_RAW_FILTER: 574 if (optlen % sizeof(struct can_filter) != 0) 575 return -EINVAL; 576 577 if (optlen > CAN_RAW_FILTER_MAX * sizeof(struct can_filter)) 578 return -EINVAL; 579 580 count = optlen / sizeof(struct can_filter); 581 582 if (count > 1) { 583 /* filter does not fit into dfilter => alloc space */ 584 filter = memdup_sockptr(optval, optlen); 585 if (IS_ERR(filter)) 586 return PTR_ERR(filter); 587 } else if (count == 1) { 588 if (copy_from_sockptr(&sfilter, optval, sizeof(sfilter))) 589 return -EFAULT; 590 } 591 592 rtnl_lock(); 593 lock_sock(sk); 594 595 dev = ro->dev; 596 if (ro->bound && dev) { 597 if (dev->reg_state != NETREG_REGISTERED) { 598 if (count > 1) 599 kfree(filter); 600 err = -ENODEV; 601 goto out_fil; 602 } 603 } 604 605 if (ro->bound) { 606 /* (try to) register the new filters */ 607 if (count == 1) 608 err = raw_enable_filters(sock_net(sk), dev, sk, 609 &sfilter, 1); 610 else 611 err = raw_enable_filters(sock_net(sk), dev, sk, 612 filter, count); 613 if (err) { 614 if (count > 1) 615 kfree(filter); 616 goto out_fil; 617 } 618 619 /* remove old filter registrations */ 620 raw_disable_filters(sock_net(sk), dev, sk, ro->filter, 621 ro->count); 622 } 623 624 /* remove old filter space */ 625 if (ro->count > 1) 626 kfree(ro->filter); 627 628 /* link new filters to the socket */ 629 if (count == 1) { 630 /* copy filter data for single filter */ 631 ro->dfilter = sfilter; 632 filter = &ro->dfilter; 633 } 634 ro->filter = filter; 635 ro->count = count; 636 637 out_fil: 638 release_sock(sk); 639 rtnl_unlock(); 640 641 break; 642 643 case CAN_RAW_ERR_FILTER: 644 if (optlen != sizeof(err_mask)) 645 return -EINVAL; 646 647 if (copy_from_sockptr(&err_mask, optval, optlen)) 648 return -EFAULT; 649 650 err_mask &= CAN_ERR_MASK; 651 652 rtnl_lock(); 653 lock_sock(sk); 654 655 dev = ro->dev; 656 if (ro->bound && dev) { 657 if (dev->reg_state != NETREG_REGISTERED) { 658 err = -ENODEV; 659 goto out_err; 660 } 661 } 662 663 /* remove current error mask */ 664 if (ro->bound) { 665 /* (try to) register the new err_mask */ 666 err = raw_enable_errfilter(sock_net(sk), dev, sk, 667 err_mask); 668 669 if (err) 670 goto out_err; 671 672 /* remove old err_mask registration */ 673 raw_disable_errfilter(sock_net(sk), dev, sk, 674 ro->err_mask); 675 } 676 677 /* link new err_mask to the socket */ 678 ro->err_mask = err_mask; 679 680 out_err: 681 release_sock(sk); 682 rtnl_unlock(); 683 684 break; 685 686 case CAN_RAW_LOOPBACK: 687 if (optlen != sizeof(flag)) 688 return -EINVAL; 689 690 if (copy_from_sockptr(&flag, optval, optlen)) 691 return -EFAULT; 692 693 ro->loopback = !!flag; 694 break; 695 696 case CAN_RAW_RECV_OWN_MSGS: 697 if (optlen != sizeof(flag)) 698 return -EINVAL; 699 700 if (copy_from_sockptr(&flag, optval, optlen)) 701 return -EFAULT; 702 703 ro->recv_own_msgs = !!flag; 704 break; 705 706 case CAN_RAW_FD_FRAMES: 707 if (optlen != sizeof(flag)) 708 return -EINVAL; 709 710 if (copy_from_sockptr(&flag, optval, optlen)) 711 return -EFAULT; 712 713 /* Enabling CAN XL includes CAN FD */ 714 if (ro->xl_frames && !flag) 715 return -EINVAL; 716 717 ro->fd_frames = !!flag; 718 break; 719 720 case CAN_RAW_XL_FRAMES: 721 if (optlen != sizeof(flag)) 722 return -EINVAL; 723 724 if (copy_from_sockptr(&flag, optval, optlen)) 725 return -EFAULT; 726 727 ro->xl_frames = !!flag; 728 729 /* Enabling CAN XL includes CAN FD */ 730 if (ro->xl_frames) 731 ro->fd_frames = ro->xl_frames; 732 break; 733 734 case CAN_RAW_XL_VCID_OPTS: 735 if (optlen != sizeof(ro->raw_vcid_opts)) 736 return -EINVAL; 737 738 if (copy_from_sockptr(&ro->raw_vcid_opts, optval, optlen)) 739 return -EFAULT; 740 741 /* prepare 32 bit values for handling in hot path */ 742 ro->tx_vcid_shifted = ro->raw_vcid_opts.tx_vcid << CANXL_VCID_OFFSET; 743 ro->rx_vcid_shifted = ro->raw_vcid_opts.rx_vcid << CANXL_VCID_OFFSET; 744 ro->rx_vcid_mask_shifted = ro->raw_vcid_opts.rx_vcid_mask << CANXL_VCID_OFFSET; 745 break; 746 747 case CAN_RAW_JOIN_FILTERS: 748 if (optlen != sizeof(flag)) 749 return -EINVAL; 750 751 if (copy_from_sockptr(&flag, optval, optlen)) 752 return -EFAULT; 753 754 ro->join_filters = !!flag; 755 break; 756 757 default: 758 return -ENOPROTOOPT; 759 } 760 return err; 761 } 762 763 static int raw_getsockopt(struct socket *sock, int level, int optname, 764 sockopt_t *opt) 765 { 766 struct sock *sk = sock->sk; 767 struct raw_sock *ro = raw_sk(sk); 768 int flag; 769 int len; 770 void *val; 771 772 if (level != SOL_CAN_RAW) 773 return -EINVAL; 774 len = opt->optlen; 775 if (len < 0) 776 return -EINVAL; 777 778 switch (optname) { 779 case CAN_RAW_FILTER: { 780 int err = 0; 781 782 lock_sock(sk); 783 if (ro->count > 0) { 784 int fsize = ro->count * sizeof(struct can_filter); 785 786 /* user space buffer to small for filter list? */ 787 if (len < fsize) { 788 /* return -ERANGE and needed space in optlen */ 789 err = -ERANGE; 790 opt->optlen = fsize; 791 } else { 792 if (len > fsize) 793 len = fsize; 794 if (copy_to_iter(ro->filter, len, 795 &opt->iter_out) != len) 796 err = -EFAULT; 797 } 798 } else { 799 len = 0; 800 } 801 release_sock(sk); 802 803 if (!err) 804 opt->optlen = len; 805 return err; 806 } 807 case CAN_RAW_ERR_FILTER: 808 if (len > sizeof(can_err_mask_t)) 809 len = sizeof(can_err_mask_t); 810 val = &ro->err_mask; 811 break; 812 813 case CAN_RAW_LOOPBACK: 814 if (len > sizeof(int)) 815 len = sizeof(int); 816 flag = ro->loopback; 817 val = &flag; 818 break; 819 820 case CAN_RAW_RECV_OWN_MSGS: 821 if (len > sizeof(int)) 822 len = sizeof(int); 823 flag = ro->recv_own_msgs; 824 val = &flag; 825 break; 826 827 case CAN_RAW_FD_FRAMES: 828 if (len > sizeof(int)) 829 len = sizeof(int); 830 flag = ro->fd_frames; 831 val = &flag; 832 break; 833 834 case CAN_RAW_XL_FRAMES: 835 if (len > sizeof(int)) 836 len = sizeof(int); 837 flag = ro->xl_frames; 838 val = &flag; 839 break; 840 841 case CAN_RAW_XL_VCID_OPTS: { 842 int err = 0; 843 844 /* user space buffer to small for VCID opts? */ 845 if (len < sizeof(ro->raw_vcid_opts)) { 846 /* return -ERANGE and needed space in optlen */ 847 err = -ERANGE; 848 opt->optlen = sizeof(ro->raw_vcid_opts); 849 } else { 850 if (len > sizeof(ro->raw_vcid_opts)) 851 len = sizeof(ro->raw_vcid_opts); 852 if (copy_to_iter(&ro->raw_vcid_opts, len, 853 &opt->iter_out) != len) 854 err = -EFAULT; 855 } 856 if (!err) 857 opt->optlen = len; 858 return err; 859 } 860 case CAN_RAW_JOIN_FILTERS: 861 if (len > sizeof(int)) 862 len = sizeof(int); 863 flag = ro->join_filters; 864 val = &flag; 865 break; 866 867 default: 868 return -ENOPROTOOPT; 869 } 870 871 opt->optlen = len; 872 if (copy_to_iter(val, len, &opt->iter_out) != len) 873 return -EFAULT; 874 return 0; 875 } 876 877 static void raw_put_canxl_vcid(struct raw_sock *ro, struct sk_buff *skb) 878 { 879 struct canxl_frame *cxl = (struct canxl_frame *)skb->data; 880 881 /* sanitize non CAN XL bits */ 882 cxl->prio &= (CANXL_PRIO_MASK | CANXL_VCID_MASK); 883 884 /* clear VCID in CAN XL frame if pass through is disabled */ 885 if (!(ro->raw_vcid_opts.flags & CAN_RAW_XL_VCID_TX_PASS)) 886 cxl->prio &= CANXL_PRIO_MASK; 887 888 /* set VCID in CAN XL frame if enabled */ 889 if (ro->raw_vcid_opts.flags & CAN_RAW_XL_VCID_TX_SET) { 890 cxl->prio &= CANXL_PRIO_MASK; 891 cxl->prio |= ro->tx_vcid_shifted; 892 } 893 } 894 895 static unsigned int raw_check_txframe(struct raw_sock *ro, struct sk_buff *skb, 896 struct net_device *dev) 897 { 898 /* Classical CAN */ 899 if (can_is_can_skb(skb) && can_cap_enabled(dev, CAN_CAP_CC)) 900 return CAN_MTU; 901 902 /* CAN FD */ 903 if (ro->fd_frames && can_is_canfd_skb(skb) && 904 can_cap_enabled(dev, CAN_CAP_FD)) 905 return CANFD_MTU; 906 907 /* CAN XL */ 908 if (ro->xl_frames && can_is_canxl_skb(skb) && 909 can_cap_enabled(dev, CAN_CAP_XL)) 910 return CANXL_MTU; 911 912 return 0; 913 } 914 915 static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) 916 { 917 struct sock *sk = sock->sk; 918 struct raw_sock *ro = raw_sk(sk); 919 struct sockcm_cookie sockc; 920 struct sk_buff *skb; 921 struct can_skb_ext *csx; 922 struct net_device *dev; 923 unsigned int txmtu; 924 int ifindex; 925 int err = -EINVAL; 926 927 /* check for valid CAN frame sizes */ 928 if (size < CANXL_HDR_SIZE + CANXL_MIN_DLEN || size > CANXL_MTU) 929 return -EINVAL; 930 931 if (msg->msg_name) { 932 DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name); 933 934 if (msg->msg_namelen < RAW_MIN_NAMELEN) 935 return -EINVAL; 936 937 if (addr->can_family != AF_CAN) 938 return -EINVAL; 939 940 ifindex = addr->can_ifindex; 941 } else { 942 ifindex = ro->ifindex; 943 } 944 945 dev = dev_get_by_index(sock_net(sk), ifindex); 946 if (!dev) 947 return -ENXIO; 948 949 /* no sending on a CAN device in read-only mode */ 950 if (can_cap_enabled(dev, CAN_CAP_RO)) { 951 err = -EACCES; 952 goto put_dev; 953 } 954 955 skb = sock_alloc_send_skb(sk, size, msg->msg_flags & MSG_DONTWAIT, 956 &err); 957 if (!skb) 958 goto put_dev; 959 960 csx = can_skb_ext_add(skb); 961 if (!csx) { 962 kfree_skb(skb); 963 err = -ENOMEM; 964 goto put_dev; 965 } 966 967 csx->can_iif = dev->ifindex; 968 969 /* fill the skb before testing for valid CAN frames */ 970 err = memcpy_from_msg(skb_put(skb, size), msg, size); 971 if (err < 0) 972 goto free_skb; 973 974 err = -EINVAL; 975 976 /* check for valid CAN (CC/FD/XL) frame content */ 977 txmtu = raw_check_txframe(ro, skb, dev); 978 if (!txmtu) 979 goto free_skb; 980 981 /* only CANXL: clear/forward/set VCID value */ 982 if (txmtu == CANXL_MTU) 983 raw_put_canxl_vcid(ro, skb); 984 985 sockcm_init(&sockc, sk); 986 if (msg->msg_controllen) { 987 err = sock_cmsg_send(sk, msg, &sockc); 988 if (unlikely(err)) 989 goto free_skb; 990 } 991 992 skb->dev = dev; 993 skb->priority = sockc.priority; 994 skb->mark = sockc.mark; 995 skb->tstamp = sockc.transmit_time; 996 997 skb_setup_tx_timestamp(skb, &sockc); 998 999 err = can_send(skb, ro->loopback); 1000 1001 dev_put(dev); 1002 1003 if (err) 1004 goto send_failed; 1005 1006 return size; 1007 1008 free_skb: 1009 kfree_skb(skb); 1010 put_dev: 1011 dev_put(dev); 1012 send_failed: 1013 return err; 1014 } 1015 1016 static int raw_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 1017 int flags) 1018 { 1019 struct sock *sk = sock->sk; 1020 struct sk_buff *skb; 1021 int err = 0; 1022 1023 if (flags & MSG_ERRQUEUE) 1024 return sock_recv_errqueue(sk, msg, size, 1025 SOL_CAN_RAW, SCM_CAN_RAW_ERRQUEUE); 1026 1027 skb = skb_recv_datagram(sk, flags, &err); 1028 if (!skb) 1029 return err; 1030 1031 if (size < skb->len) 1032 msg->msg_flags |= MSG_TRUNC; 1033 else 1034 size = skb->len; 1035 1036 err = memcpy_to_msg(msg, skb->data, size); 1037 if (err < 0) { 1038 skb_free_datagram(sk, skb); 1039 return err; 1040 } 1041 1042 sock_recv_cmsgs(msg, sk, skb); 1043 1044 if (msg->msg_name) { 1045 __sockaddr_check_size(RAW_MIN_NAMELEN); 1046 msg->msg_namelen = RAW_MIN_NAMELEN; 1047 memcpy(msg->msg_name, skb->cb, msg->msg_namelen); 1048 } 1049 1050 /* assign the flags that have been recorded in raw_rcv() */ 1051 msg->msg_flags |= *(raw_flags(skb)); 1052 1053 skb_free_datagram(sk, skb); 1054 1055 return size; 1056 } 1057 1058 static int raw_sock_no_ioctlcmd(struct socket *sock, unsigned int cmd, 1059 unsigned long arg) 1060 { 1061 /* no ioctls for socket layer -> hand it down to NIC layer */ 1062 return -ENOIOCTLCMD; 1063 } 1064 1065 static const struct proto_ops raw_ops = { 1066 .family = PF_CAN, 1067 .release = raw_release, 1068 .bind = raw_bind, 1069 .connect = sock_no_connect, 1070 .socketpair = sock_no_socketpair, 1071 .accept = sock_no_accept, 1072 .getname = raw_getname, 1073 .poll = datagram_poll, 1074 .ioctl = raw_sock_no_ioctlcmd, 1075 .gettstamp = sock_gettstamp, 1076 .listen = sock_no_listen, 1077 .shutdown = sock_no_shutdown, 1078 .setsockopt = raw_setsockopt, 1079 .getsockopt_iter = raw_getsockopt, 1080 .sendmsg = raw_sendmsg, 1081 .recvmsg = raw_recvmsg, 1082 .mmap = sock_no_mmap, 1083 }; 1084 1085 static struct proto raw_proto __read_mostly = { 1086 .name = "CAN_RAW", 1087 .owner = THIS_MODULE, 1088 .obj_size = sizeof(struct raw_sock), 1089 .init = raw_init, 1090 }; 1091 1092 static const struct can_proto raw_can_proto = { 1093 .type = SOCK_RAW, 1094 .protocol = CAN_RAW, 1095 .ops = &raw_ops, 1096 .prot = &raw_proto, 1097 }; 1098 1099 static struct notifier_block canraw_notifier = { 1100 .notifier_call = raw_notifier 1101 }; 1102 1103 static __init int raw_module_init(void) 1104 { 1105 int err; 1106 1107 pr_info("can: raw protocol\n"); 1108 1109 err = register_netdevice_notifier(&canraw_notifier); 1110 if (err) 1111 return err; 1112 1113 err = can_proto_register(&raw_can_proto); 1114 if (err < 0) { 1115 pr_err("can: registration of raw protocol failed\n"); 1116 goto register_proto_failed; 1117 } 1118 1119 return 0; 1120 1121 register_proto_failed: 1122 unregister_netdevice_notifier(&canraw_notifier); 1123 return err; 1124 } 1125 1126 static __exit void raw_module_exit(void) 1127 { 1128 can_proto_unregister(&raw_can_proto); 1129 unregister_netdevice_notifier(&canraw_notifier); 1130 } 1131 1132 module_init(raw_module_init); 1133 module_exit(raw_module_exit); 1134