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 void raw_sock_destruct(struct sock *sk) 366 { 367 struct raw_sock *ro = raw_sk(sk); 368 369 free_percpu(ro->uniq); 370 can_sock_destruct(sk); 371 } 372 373 static int raw_init(struct sock *sk) 374 { 375 struct raw_sock *ro = raw_sk(sk); 376 377 ro->bound = 0; 378 ro->ifindex = 0; 379 ro->dev = NULL; 380 381 /* set default filter to single entry dfilter */ 382 ro->dfilter.can_id = 0; 383 ro->dfilter.can_mask = MASK_ALL; 384 ro->filter = &ro->dfilter; 385 ro->count = 1; 386 387 /* set default loopback behaviour */ 388 ro->loopback = 1; 389 ro->recv_own_msgs = 0; 390 ro->fd_frames = 0; 391 ro->xl_frames = 0; 392 ro->join_filters = 0; 393 394 /* alloc_percpu provides zero'ed memory */ 395 ro->uniq = alloc_percpu(struct uniqframe); 396 if (unlikely(!ro->uniq)) 397 return -ENOMEM; 398 399 sk->sk_destruct = raw_sock_destruct; 400 401 /* set notifier */ 402 spin_lock(&raw_notifier_lock); 403 list_add_tail(&ro->notifier, &raw_notifier_list); 404 spin_unlock(&raw_notifier_lock); 405 406 return 0; 407 } 408 409 static int raw_release(struct socket *sock) 410 { 411 struct sock *sk = sock->sk; 412 struct raw_sock *ro; 413 struct net *net; 414 415 if (!sk) 416 return 0; 417 418 ro = raw_sk(sk); 419 net = sock_net(sk); 420 421 spin_lock(&raw_notifier_lock); 422 while (raw_busy_notifier == ro) { 423 spin_unlock(&raw_notifier_lock); 424 schedule_timeout_uninterruptible(1); 425 spin_lock(&raw_notifier_lock); 426 } 427 list_del(&ro->notifier); 428 spin_unlock(&raw_notifier_lock); 429 430 rtnl_lock(); 431 lock_sock(sk); 432 433 /* remove current filters & unregister */ 434 if (ro->bound) { 435 if (ro->dev) { 436 raw_disable_allfilters(dev_net(ro->dev), ro->dev, sk); 437 netdev_put(ro->dev, &ro->dev_tracker); 438 } else { 439 raw_disable_allfilters(net, NULL, sk); 440 } 441 } 442 443 if (ro->count > 1) 444 kfree(ro->filter); 445 446 ro->ifindex = 0; 447 ro->bound = 0; 448 ro->dev = NULL; 449 ro->count = 0; 450 451 sock_orphan(sk); 452 sock->sk = NULL; 453 454 release_sock(sk); 455 rtnl_unlock(); 456 457 sock_prot_inuse_add(net, sk->sk_prot, -1); 458 sock_put(sk); 459 460 return 0; 461 } 462 463 static int raw_bind(struct socket *sock, struct sockaddr_unsized *uaddr, int len) 464 { 465 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; 466 struct sock *sk = sock->sk; 467 struct raw_sock *ro = raw_sk(sk); 468 struct net_device *dev = NULL; 469 int ifindex; 470 int err = 0; 471 int notify_enetdown = 0; 472 473 if (len < RAW_MIN_NAMELEN) 474 return -EINVAL; 475 if (addr->can_family != AF_CAN) 476 return -EINVAL; 477 478 rtnl_lock(); 479 lock_sock(sk); 480 481 if (ro->bound && addr->can_ifindex == ro->ifindex) 482 goto out; 483 484 if (addr->can_ifindex) { 485 dev = dev_get_by_index(sock_net(sk), addr->can_ifindex); 486 if (!dev) { 487 err = -ENODEV; 488 goto out; 489 } 490 if (dev->type != ARPHRD_CAN) { 491 err = -ENODEV; 492 goto out_put_dev; 493 } 494 495 if (!(dev->flags & IFF_UP)) 496 notify_enetdown = 1; 497 498 ifindex = dev->ifindex; 499 500 /* filters set by default/setsockopt */ 501 err = raw_enable_allfilters(sock_net(sk), dev, sk); 502 if (err) 503 goto out_put_dev; 504 505 } else { 506 ifindex = 0; 507 508 /* filters set by default/setsockopt */ 509 err = raw_enable_allfilters(sock_net(sk), NULL, sk); 510 } 511 512 if (!err) { 513 if (ro->bound) { 514 /* unregister old filters */ 515 if (ro->dev) { 516 raw_disable_allfilters(dev_net(ro->dev), 517 ro->dev, sk); 518 /* drop reference to old ro->dev */ 519 netdev_put(ro->dev, &ro->dev_tracker); 520 } else { 521 raw_disable_allfilters(sock_net(sk), NULL, sk); 522 } 523 } 524 ro->ifindex = ifindex; 525 ro->bound = 1; 526 /* bind() ok -> hold a reference for new ro->dev */ 527 ro->dev = dev; 528 if (ro->dev) 529 netdev_hold(ro->dev, &ro->dev_tracker, GFP_KERNEL); 530 } 531 532 out_put_dev: 533 /* remove potential reference from dev_get_by_index() */ 534 dev_put(dev); 535 out: 536 release_sock(sk); 537 rtnl_unlock(); 538 539 if (notify_enetdown) { 540 sk->sk_err = ENETDOWN; 541 if (!sock_flag(sk, SOCK_DEAD)) 542 sk_error_report(sk); 543 } 544 545 return err; 546 } 547 548 static int raw_getname(struct socket *sock, struct sockaddr *uaddr, 549 int peer) 550 { 551 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; 552 struct sock *sk = sock->sk; 553 struct raw_sock *ro = raw_sk(sk); 554 555 if (peer) 556 return -EOPNOTSUPP; 557 558 memset(addr, 0, RAW_MIN_NAMELEN); 559 addr->can_family = AF_CAN; 560 addr->can_ifindex = ro->ifindex; 561 562 return RAW_MIN_NAMELEN; 563 } 564 565 static int raw_setsockopt(struct socket *sock, int level, int optname, 566 sockptr_t optval, unsigned int optlen) 567 { 568 struct sock *sk = sock->sk; 569 struct raw_sock *ro = raw_sk(sk); 570 struct can_filter *filter = NULL; /* dyn. alloc'ed filters */ 571 struct can_filter sfilter; /* single filter */ 572 struct net_device *dev = NULL; 573 can_err_mask_t err_mask = 0; 574 int count = 0; 575 int flag; 576 int err = 0; 577 578 if (level != SOL_CAN_RAW) 579 return -EINVAL; 580 581 switch (optname) { 582 case CAN_RAW_FILTER: 583 if (optlen % sizeof(struct can_filter) != 0) 584 return -EINVAL; 585 586 if (optlen > CAN_RAW_FILTER_MAX * sizeof(struct can_filter)) 587 return -EINVAL; 588 589 count = optlen / sizeof(struct can_filter); 590 591 if (count > 1) { 592 /* filter does not fit into dfilter => alloc space */ 593 filter = memdup_sockptr(optval, optlen); 594 if (IS_ERR(filter)) 595 return PTR_ERR(filter); 596 } else if (count == 1) { 597 if (copy_from_sockptr(&sfilter, optval, sizeof(sfilter))) 598 return -EFAULT; 599 } 600 601 rtnl_lock(); 602 lock_sock(sk); 603 604 dev = ro->dev; 605 if (ro->bound && dev) { 606 if (dev->reg_state != NETREG_REGISTERED) { 607 if (count > 1) 608 kfree(filter); 609 err = -ENODEV; 610 goto out_fil; 611 } 612 } 613 614 if (ro->bound) { 615 /* (try to) register the new filters */ 616 if (count == 1) 617 err = raw_enable_filters(sock_net(sk), dev, sk, 618 &sfilter, 1); 619 else 620 err = raw_enable_filters(sock_net(sk), dev, sk, 621 filter, count); 622 if (err) { 623 if (count > 1) 624 kfree(filter); 625 goto out_fil; 626 } 627 628 /* remove old filter registrations */ 629 raw_disable_filters(sock_net(sk), dev, sk, ro->filter, 630 ro->count); 631 } 632 633 /* remove old filter space */ 634 if (ro->count > 1) 635 kfree(ro->filter); 636 637 /* link new filters to the socket */ 638 if (count == 1) { 639 /* copy filter data for single filter */ 640 ro->dfilter = sfilter; 641 filter = &ro->dfilter; 642 } 643 ro->filter = filter; 644 ro->count = count; 645 646 out_fil: 647 release_sock(sk); 648 rtnl_unlock(); 649 650 break; 651 652 case CAN_RAW_ERR_FILTER: 653 if (optlen != sizeof(err_mask)) 654 return -EINVAL; 655 656 if (copy_from_sockptr(&err_mask, optval, optlen)) 657 return -EFAULT; 658 659 err_mask &= CAN_ERR_MASK; 660 661 rtnl_lock(); 662 lock_sock(sk); 663 664 dev = ro->dev; 665 if (ro->bound && dev) { 666 if (dev->reg_state != NETREG_REGISTERED) { 667 err = -ENODEV; 668 goto out_err; 669 } 670 } 671 672 /* remove current error mask */ 673 if (ro->bound) { 674 /* (try to) register the new err_mask */ 675 err = raw_enable_errfilter(sock_net(sk), dev, sk, 676 err_mask); 677 678 if (err) 679 goto out_err; 680 681 /* remove old err_mask registration */ 682 raw_disable_errfilter(sock_net(sk), dev, sk, 683 ro->err_mask); 684 } 685 686 /* link new err_mask to the socket */ 687 ro->err_mask = err_mask; 688 689 out_err: 690 release_sock(sk); 691 rtnl_unlock(); 692 693 break; 694 695 case CAN_RAW_LOOPBACK: 696 if (optlen != sizeof(flag)) 697 return -EINVAL; 698 699 if (copy_from_sockptr(&flag, optval, optlen)) 700 return -EFAULT; 701 702 ro->loopback = !!flag; 703 break; 704 705 case CAN_RAW_RECV_OWN_MSGS: 706 if (optlen != sizeof(flag)) 707 return -EINVAL; 708 709 if (copy_from_sockptr(&flag, optval, optlen)) 710 return -EFAULT; 711 712 ro->recv_own_msgs = !!flag; 713 break; 714 715 case CAN_RAW_FD_FRAMES: 716 if (optlen != sizeof(flag)) 717 return -EINVAL; 718 719 if (copy_from_sockptr(&flag, optval, optlen)) 720 return -EFAULT; 721 722 /* Enabling CAN XL includes CAN FD */ 723 if (ro->xl_frames && !flag) 724 return -EINVAL; 725 726 ro->fd_frames = !!flag; 727 break; 728 729 case CAN_RAW_XL_FRAMES: 730 if (optlen != sizeof(flag)) 731 return -EINVAL; 732 733 if (copy_from_sockptr(&flag, optval, optlen)) 734 return -EFAULT; 735 736 ro->xl_frames = !!flag; 737 738 /* Enabling CAN XL includes CAN FD */ 739 if (ro->xl_frames) 740 ro->fd_frames = ro->xl_frames; 741 break; 742 743 case CAN_RAW_XL_VCID_OPTS: 744 if (optlen != sizeof(ro->raw_vcid_opts)) 745 return -EINVAL; 746 747 if (copy_from_sockptr(&ro->raw_vcid_opts, optval, optlen)) 748 return -EFAULT; 749 750 /* prepare 32 bit values for handling in hot path */ 751 ro->tx_vcid_shifted = ro->raw_vcid_opts.tx_vcid << CANXL_VCID_OFFSET; 752 ro->rx_vcid_shifted = ro->raw_vcid_opts.rx_vcid << CANXL_VCID_OFFSET; 753 ro->rx_vcid_mask_shifted = ro->raw_vcid_opts.rx_vcid_mask << CANXL_VCID_OFFSET; 754 break; 755 756 case CAN_RAW_JOIN_FILTERS: 757 if (optlen != sizeof(flag)) 758 return -EINVAL; 759 760 if (copy_from_sockptr(&flag, optval, optlen)) 761 return -EFAULT; 762 763 ro->join_filters = !!flag; 764 break; 765 766 default: 767 return -ENOPROTOOPT; 768 } 769 return err; 770 } 771 772 static int raw_getsockopt(struct socket *sock, int level, int optname, 773 sockopt_t *opt) 774 { 775 struct sock *sk = sock->sk; 776 struct raw_sock *ro = raw_sk(sk); 777 int flag; 778 int len; 779 void *val; 780 781 if (level != SOL_CAN_RAW) 782 return -EINVAL; 783 len = opt->optlen; 784 if (len < 0) 785 return -EINVAL; 786 787 switch (optname) { 788 case CAN_RAW_FILTER: { 789 int err = 0; 790 791 lock_sock(sk); 792 if (ro->count > 0) { 793 int fsize = ro->count * sizeof(struct can_filter); 794 795 /* user space buffer to small for filter list? */ 796 if (len < fsize) { 797 /* return -ERANGE and needed space in optlen */ 798 err = -ERANGE; 799 opt->optlen = fsize; 800 } else { 801 if (len > fsize) 802 len = fsize; 803 if (copy_to_iter(ro->filter, len, 804 &opt->iter_out) != len) 805 err = -EFAULT; 806 } 807 } else { 808 len = 0; 809 } 810 release_sock(sk); 811 812 if (!err) 813 opt->optlen = len; 814 return err; 815 } 816 case CAN_RAW_ERR_FILTER: 817 if (len > sizeof(can_err_mask_t)) 818 len = sizeof(can_err_mask_t); 819 val = &ro->err_mask; 820 break; 821 822 case CAN_RAW_LOOPBACK: 823 if (len > sizeof(int)) 824 len = sizeof(int); 825 flag = ro->loopback; 826 val = &flag; 827 break; 828 829 case CAN_RAW_RECV_OWN_MSGS: 830 if (len > sizeof(int)) 831 len = sizeof(int); 832 flag = ro->recv_own_msgs; 833 val = &flag; 834 break; 835 836 case CAN_RAW_FD_FRAMES: 837 if (len > sizeof(int)) 838 len = sizeof(int); 839 flag = ro->fd_frames; 840 val = &flag; 841 break; 842 843 case CAN_RAW_XL_FRAMES: 844 if (len > sizeof(int)) 845 len = sizeof(int); 846 flag = ro->xl_frames; 847 val = &flag; 848 break; 849 850 case CAN_RAW_XL_VCID_OPTS: { 851 int err = 0; 852 853 /* user space buffer to small for VCID opts? */ 854 if (len < sizeof(ro->raw_vcid_opts)) { 855 /* return -ERANGE and needed space in optlen */ 856 err = -ERANGE; 857 opt->optlen = sizeof(ro->raw_vcid_opts); 858 } else { 859 if (len > sizeof(ro->raw_vcid_opts)) 860 len = sizeof(ro->raw_vcid_opts); 861 if (copy_to_iter(&ro->raw_vcid_opts, len, 862 &opt->iter_out) != len) 863 err = -EFAULT; 864 } 865 if (!err) 866 opt->optlen = len; 867 return err; 868 } 869 case CAN_RAW_JOIN_FILTERS: 870 if (len > sizeof(int)) 871 len = sizeof(int); 872 flag = ro->join_filters; 873 val = &flag; 874 break; 875 876 default: 877 return -ENOPROTOOPT; 878 } 879 880 opt->optlen = len; 881 if (copy_to_iter(val, len, &opt->iter_out) != len) 882 return -EFAULT; 883 return 0; 884 } 885 886 static void raw_put_canxl_vcid(struct raw_sock *ro, struct sk_buff *skb) 887 { 888 struct canxl_frame *cxl = (struct canxl_frame *)skb->data; 889 890 /* sanitize non CAN XL bits */ 891 cxl->prio &= (CANXL_PRIO_MASK | CANXL_VCID_MASK); 892 893 /* clear VCID in CAN XL frame if pass through is disabled */ 894 if (!(ro->raw_vcid_opts.flags & CAN_RAW_XL_VCID_TX_PASS)) 895 cxl->prio &= CANXL_PRIO_MASK; 896 897 /* set VCID in CAN XL frame if enabled */ 898 if (ro->raw_vcid_opts.flags & CAN_RAW_XL_VCID_TX_SET) { 899 cxl->prio &= CANXL_PRIO_MASK; 900 cxl->prio |= ro->tx_vcid_shifted; 901 } 902 } 903 904 static unsigned int raw_check_txframe(struct raw_sock *ro, struct sk_buff *skb, 905 struct net_device *dev) 906 { 907 /* Classical CAN */ 908 if (can_is_can_skb(skb) && can_cap_enabled(dev, CAN_CAP_CC)) 909 return CAN_MTU; 910 911 /* CAN FD */ 912 if (ro->fd_frames && can_is_canfd_skb(skb) && 913 can_cap_enabled(dev, CAN_CAP_FD)) 914 return CANFD_MTU; 915 916 /* CAN XL */ 917 if (ro->xl_frames && can_is_canxl_skb(skb) && 918 can_cap_enabled(dev, CAN_CAP_XL)) 919 return CANXL_MTU; 920 921 return 0; 922 } 923 924 static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) 925 { 926 struct sock *sk = sock->sk; 927 struct raw_sock *ro = raw_sk(sk); 928 struct sockcm_cookie sockc; 929 struct sk_buff *skb; 930 struct can_skb_ext *csx; 931 struct net_device *dev; 932 unsigned int txmtu; 933 int ifindex; 934 int err = -EINVAL; 935 936 /* check for valid CAN frame sizes */ 937 if (size < CANXL_HDR_SIZE + CANXL_MIN_DLEN || size > CANXL_MTU) 938 return -EINVAL; 939 940 if (msg->msg_name) { 941 DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name); 942 943 if (msg->msg_namelen < RAW_MIN_NAMELEN) 944 return -EINVAL; 945 946 if (addr->can_family != AF_CAN) 947 return -EINVAL; 948 949 ifindex = addr->can_ifindex; 950 } else { 951 ifindex = ro->ifindex; 952 } 953 954 dev = dev_get_by_index(sock_net(sk), ifindex); 955 if (!dev) 956 return -ENXIO; 957 958 /* no sending on a CAN device in read-only mode */ 959 if (can_cap_enabled(dev, CAN_CAP_RO)) { 960 err = -EACCES; 961 goto put_dev; 962 } 963 964 skb = sock_alloc_send_skb(sk, size, msg->msg_flags & MSG_DONTWAIT, 965 &err); 966 if (!skb) 967 goto put_dev; 968 969 csx = can_skb_ext_add(skb); 970 if (!csx) { 971 kfree_skb(skb); 972 err = -ENOMEM; 973 goto put_dev; 974 } 975 976 csx->can_iif = dev->ifindex; 977 978 /* fill the skb before testing for valid CAN frames */ 979 err = memcpy_from_msg(skb_put(skb, size), msg, size); 980 if (err < 0) 981 goto free_skb; 982 983 err = -EINVAL; 984 985 /* check for valid CAN (CC/FD/XL) frame content */ 986 txmtu = raw_check_txframe(ro, skb, dev); 987 if (!txmtu) 988 goto free_skb; 989 990 /* only CANXL: clear/forward/set VCID value */ 991 if (txmtu == CANXL_MTU) 992 raw_put_canxl_vcid(ro, skb); 993 994 sockcm_init(&sockc, sk); 995 if (msg->msg_controllen) { 996 err = sock_cmsg_send(sk, msg, &sockc); 997 if (unlikely(err)) 998 goto free_skb; 999 } 1000 1001 skb->dev = dev; 1002 skb->priority = sockc.priority; 1003 skb->mark = sockc.mark; 1004 skb->tstamp = sockc.transmit_time; 1005 1006 skb_setup_tx_timestamp(skb, &sockc); 1007 1008 err = can_send(skb, ro->loopback); 1009 1010 dev_put(dev); 1011 1012 if (err) 1013 goto send_failed; 1014 1015 return size; 1016 1017 free_skb: 1018 kfree_skb(skb); 1019 put_dev: 1020 dev_put(dev); 1021 send_failed: 1022 return err; 1023 } 1024 1025 static int raw_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 1026 int flags) 1027 { 1028 struct sock *sk = sock->sk; 1029 struct sk_buff *skb; 1030 int err = 0; 1031 1032 if (flags & MSG_ERRQUEUE) 1033 return sock_recv_errqueue(sk, msg, size, 1034 SOL_CAN_RAW, SCM_CAN_RAW_ERRQUEUE); 1035 1036 skb = skb_recv_datagram(sk, flags, &err); 1037 if (!skb) 1038 return err; 1039 1040 if (size < skb->len) 1041 msg->msg_flags |= MSG_TRUNC; 1042 else 1043 size = skb->len; 1044 1045 err = memcpy_to_msg(msg, skb->data, size); 1046 if (err < 0) { 1047 skb_free_datagram(sk, skb); 1048 return err; 1049 } 1050 1051 sock_recv_cmsgs(msg, sk, skb); 1052 1053 if (msg->msg_name) { 1054 __sockaddr_check_size(RAW_MIN_NAMELEN); 1055 msg->msg_namelen = RAW_MIN_NAMELEN; 1056 memcpy(msg->msg_name, skb->cb, msg->msg_namelen); 1057 } 1058 1059 /* assign the flags that have been recorded in raw_rcv() */ 1060 msg->msg_flags |= *(raw_flags(skb)); 1061 1062 skb_free_datagram(sk, skb); 1063 1064 return size; 1065 } 1066 1067 static int raw_sock_no_ioctlcmd(struct socket *sock, unsigned int cmd, 1068 unsigned long arg) 1069 { 1070 /* no ioctls for socket layer -> hand it down to NIC layer */ 1071 return -ENOIOCTLCMD; 1072 } 1073 1074 static const struct proto_ops raw_ops = { 1075 .family = PF_CAN, 1076 .release = raw_release, 1077 .bind = raw_bind, 1078 .connect = sock_no_connect, 1079 .socketpair = sock_no_socketpair, 1080 .accept = sock_no_accept, 1081 .getname = raw_getname, 1082 .poll = datagram_poll, 1083 .ioctl = raw_sock_no_ioctlcmd, 1084 .gettstamp = sock_gettstamp, 1085 .listen = sock_no_listen, 1086 .shutdown = sock_no_shutdown, 1087 .setsockopt = raw_setsockopt, 1088 .getsockopt_iter = raw_getsockopt, 1089 .sendmsg = raw_sendmsg, 1090 .recvmsg = raw_recvmsg, 1091 .mmap = sock_no_mmap, 1092 }; 1093 1094 static struct proto raw_proto __read_mostly = { 1095 .name = "CAN_RAW", 1096 .owner = THIS_MODULE, 1097 .obj_size = sizeof(struct raw_sock), 1098 .init = raw_init, 1099 }; 1100 1101 static const struct can_proto raw_can_proto = { 1102 .type = SOCK_RAW, 1103 .protocol = CAN_RAW, 1104 .ops = &raw_ops, 1105 .prot = &raw_proto, 1106 }; 1107 1108 static struct notifier_block canraw_notifier = { 1109 .notifier_call = raw_notifier 1110 }; 1111 1112 static __init int raw_module_init(void) 1113 { 1114 int err; 1115 1116 pr_info("can: raw protocol\n"); 1117 1118 err = register_netdevice_notifier(&canraw_notifier); 1119 if (err) 1120 return err; 1121 1122 err = can_proto_register(&raw_can_proto); 1123 if (err < 0) { 1124 pr_err("can: registration of raw protocol failed\n"); 1125 goto register_proto_failed; 1126 } 1127 1128 return 0; 1129 1130 register_proto_failed: 1131 unregister_netdevice_notifier(&canraw_notifier); 1132 return err; 1133 } 1134 1135 static __exit void raw_module_exit(void) 1136 { 1137 can_proto_unregister(&raw_can_proto); 1138 unregister_netdevice_notifier(&canraw_notifier); 1139 } 1140 1141 module_init(raw_module_init); 1142 module_exit(raw_module_exit); 1143