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 can_skb_uid; 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 struct can_skb_ext *csx = can_skb_ext_find(oskb); 137 unsigned int *pflags; 138 139 /* check the received tx sock reference */ 140 if (!ro->recv_own_msgs && oskb->sk == sk) 141 return; 142 143 if (WARN_ON_ONCE(!csx)) 144 return; 145 146 /* make sure to not pass oversized frames to the socket */ 147 if (!ro->fd_frames && can_is_canfd_skb(oskb)) 148 return; 149 150 if (can_is_canxl_skb(oskb)) { 151 struct canxl_frame *cxl = (struct canxl_frame *)oskb->data; 152 153 /* make sure to not pass oversized frames to the socket */ 154 if (!ro->xl_frames) 155 return; 156 157 /* filter CAN XL VCID content */ 158 if (ro->raw_vcid_opts.flags & CAN_RAW_XL_VCID_RX_FILTER) { 159 /* apply VCID filter if user enabled the filter */ 160 if ((cxl->prio & ro->rx_vcid_mask_shifted) != 161 (ro->rx_vcid_shifted & ro->rx_vcid_mask_shifted)) 162 return; 163 } else { 164 /* no filter => do not forward VCID tagged frames */ 165 if (cxl->prio & CANXL_VCID_MASK) 166 return; 167 } 168 } 169 170 /* eliminate multiple filter matches for the same skb */ 171 if (this_cpu_ptr(ro->uniq)->skb == oskb && 172 this_cpu_ptr(ro->uniq)->can_skb_uid == csx->can_skb_uid) { 173 if (!ro->join_filters) 174 return; 175 176 this_cpu_inc(ro->uniq->join_rx_count); 177 /* drop frame until all enabled filters matched */ 178 if (this_cpu_ptr(ro->uniq)->join_rx_count < ro->count) 179 return; 180 } else { 181 this_cpu_ptr(ro->uniq)->skb = oskb; 182 this_cpu_ptr(ro->uniq)->can_skb_uid = csx->can_skb_uid; 183 this_cpu_ptr(ro->uniq)->join_rx_count = 1; 184 /* drop first frame to check all enabled filters? */ 185 if (ro->join_filters && ro->count > 1) 186 return; 187 } 188 189 /* clone the given skb to be able to enqueue it into the rcv queue */ 190 skb = skb_clone(oskb, GFP_ATOMIC); 191 if (!skb) 192 return; 193 194 /* Put the datagram to the queue so that raw_recvmsg() can get 195 * it from there. We need to pass the interface index to 196 * raw_recvmsg(). We pass a whole struct sockaddr_can in 197 * skb->cb containing the interface index. 198 */ 199 200 sock_skb_cb_check_size(sizeof(struct sockaddr_can)); 201 addr = (struct sockaddr_can *)skb->cb; 202 memset(addr, 0, sizeof(*addr)); 203 addr->can_family = AF_CAN; 204 addr->can_ifindex = skb->dev->ifindex; 205 206 /* add CAN specific message flags for raw_recvmsg() */ 207 pflags = raw_flags(skb); 208 *pflags = 0; 209 if (oskb->sk) 210 *pflags |= MSG_DONTROUTE; 211 if (oskb->sk == sk) 212 *pflags |= MSG_CONFIRM; 213 214 reason = sock_queue_rcv_skb_reason(sk, skb); 215 if (reason) 216 sk_skb_reason_drop(sk, skb, reason); 217 } 218 219 static int raw_enable_filters(struct net *net, struct net_device *dev, 220 struct sock *sk, struct can_filter *filter, 221 int count) 222 { 223 int err = 0; 224 int i; 225 226 for (i = 0; i < count; i++) { 227 err = can_rx_register(net, dev, filter[i].can_id, 228 filter[i].can_mask, 229 raw_rcv, sk, "raw", sk); 230 if (err) { 231 /* clean up successfully registered filters */ 232 while (--i >= 0) 233 can_rx_unregister(net, dev, filter[i].can_id, 234 filter[i].can_mask, 235 raw_rcv, sk); 236 break; 237 } 238 } 239 240 return err; 241 } 242 243 static int raw_enable_errfilter(struct net *net, struct net_device *dev, 244 struct sock *sk, can_err_mask_t err_mask) 245 { 246 int err = 0; 247 248 if (err_mask) 249 err = can_rx_register(net, dev, 0, err_mask | CAN_ERR_FLAG, 250 raw_rcv, sk, "raw", sk); 251 252 return err; 253 } 254 255 static void raw_disable_filters(struct net *net, struct net_device *dev, 256 struct sock *sk, struct can_filter *filter, 257 int count) 258 { 259 int i; 260 261 for (i = 0; i < count; i++) 262 can_rx_unregister(net, dev, filter[i].can_id, 263 filter[i].can_mask, raw_rcv, sk); 264 } 265 266 static inline void raw_disable_errfilter(struct net *net, 267 struct net_device *dev, 268 struct sock *sk, 269 can_err_mask_t err_mask) 270 271 { 272 if (err_mask) 273 can_rx_unregister(net, dev, 0, err_mask | CAN_ERR_FLAG, 274 raw_rcv, sk); 275 } 276 277 static inline void raw_disable_allfilters(struct net *net, 278 struct net_device *dev, 279 struct sock *sk) 280 { 281 struct raw_sock *ro = raw_sk(sk); 282 283 raw_disable_filters(net, dev, sk, ro->filter, ro->count); 284 raw_disable_errfilter(net, dev, sk, ro->err_mask); 285 } 286 287 static int raw_enable_allfilters(struct net *net, struct net_device *dev, 288 struct sock *sk) 289 { 290 struct raw_sock *ro = raw_sk(sk); 291 int err; 292 293 err = raw_enable_filters(net, dev, sk, ro->filter, ro->count); 294 if (!err) { 295 err = raw_enable_errfilter(net, dev, sk, ro->err_mask); 296 if (err) 297 raw_disable_filters(net, dev, sk, ro->filter, 298 ro->count); 299 } 300 301 return err; 302 } 303 304 static void raw_notify(struct raw_sock *ro, unsigned long msg, 305 struct net_device *dev) 306 { 307 struct sock *sk = &ro->sk; 308 309 if (!net_eq(dev_net(dev), sock_net(sk))) 310 return; 311 312 if (ro->dev != dev) 313 return; 314 315 switch (msg) { 316 case NETDEV_UNREGISTER: 317 lock_sock(sk); 318 /* remove current filters & unregister */ 319 if (ro->bound) { 320 raw_disable_allfilters(dev_net(dev), dev, sk); 321 netdev_put(dev, &ro->dev_tracker); 322 } 323 324 if (ro->count > 1) 325 kfree(ro->filter); 326 327 ro->ifindex = 0; 328 ro->bound = 0; 329 ro->dev = NULL; 330 ro->count = 0; 331 release_sock(sk); 332 333 sk->sk_err = ENODEV; 334 if (!sock_flag(sk, SOCK_DEAD)) 335 sk_error_report(sk); 336 break; 337 338 case NETDEV_DOWN: 339 sk->sk_err = ENETDOWN; 340 if (!sock_flag(sk, SOCK_DEAD)) 341 sk_error_report(sk); 342 break; 343 } 344 } 345 346 static int raw_notifier(struct notifier_block *nb, unsigned long msg, 347 void *ptr) 348 { 349 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 350 351 if (dev->type != ARPHRD_CAN) 352 return NOTIFY_DONE; 353 if (msg != NETDEV_UNREGISTER && msg != NETDEV_DOWN) 354 return NOTIFY_DONE; 355 if (unlikely(raw_busy_notifier)) /* Check for reentrant bug. */ 356 return NOTIFY_DONE; 357 358 spin_lock(&raw_notifier_lock); 359 list_for_each_entry(raw_busy_notifier, &raw_notifier_list, notifier) { 360 spin_unlock(&raw_notifier_lock); 361 raw_notify(raw_busy_notifier, msg, dev); 362 spin_lock(&raw_notifier_lock); 363 } 364 raw_busy_notifier = NULL; 365 spin_unlock(&raw_notifier_lock); 366 return NOTIFY_DONE; 367 } 368 369 static void raw_sock_destruct(struct sock *sk) 370 { 371 struct raw_sock *ro = raw_sk(sk); 372 373 free_percpu(ro->uniq); 374 can_sock_destruct(sk); 375 } 376 377 static int raw_init(struct sock *sk) 378 { 379 struct raw_sock *ro = raw_sk(sk); 380 381 ro->bound = 0; 382 ro->ifindex = 0; 383 ro->dev = NULL; 384 385 /* set default filter to single entry dfilter */ 386 ro->dfilter.can_id = 0; 387 ro->dfilter.can_mask = MASK_ALL; 388 ro->filter = &ro->dfilter; 389 ro->count = 1; 390 391 /* set default loopback behaviour */ 392 ro->loopback = 1; 393 ro->recv_own_msgs = 0; 394 ro->fd_frames = 0; 395 ro->xl_frames = 0; 396 ro->join_filters = 0; 397 398 /* alloc_percpu provides zero'ed memory */ 399 ro->uniq = alloc_percpu(struct uniqframe); 400 if (unlikely(!ro->uniq)) 401 return -ENOMEM; 402 403 sk->sk_destruct = raw_sock_destruct; 404 405 /* set notifier */ 406 spin_lock(&raw_notifier_lock); 407 list_add_tail(&ro->notifier, &raw_notifier_list); 408 spin_unlock(&raw_notifier_lock); 409 410 return 0; 411 } 412 413 static int raw_release(struct socket *sock) 414 { 415 struct sock *sk = sock->sk; 416 struct raw_sock *ro; 417 struct net *net; 418 419 if (!sk) 420 return 0; 421 422 ro = raw_sk(sk); 423 net = sock_net(sk); 424 425 spin_lock(&raw_notifier_lock); 426 while (raw_busy_notifier == ro) { 427 spin_unlock(&raw_notifier_lock); 428 schedule_timeout_uninterruptible(1); 429 spin_lock(&raw_notifier_lock); 430 } 431 list_del(&ro->notifier); 432 spin_unlock(&raw_notifier_lock); 433 434 rtnl_lock(); 435 lock_sock(sk); 436 437 /* remove current filters & unregister */ 438 if (ro->bound) { 439 if (ro->dev) { 440 raw_disable_allfilters(dev_net(ro->dev), ro->dev, sk); 441 netdev_put(ro->dev, &ro->dev_tracker); 442 } else { 443 raw_disable_allfilters(net, NULL, sk); 444 } 445 } 446 447 if (ro->count > 1) 448 kfree(ro->filter); 449 450 ro->ifindex = 0; 451 ro->bound = 0; 452 ro->dev = NULL; 453 ro->count = 0; 454 455 sock_orphan(sk); 456 sock->sk = NULL; 457 458 release_sock(sk); 459 rtnl_unlock(); 460 461 sock_prot_inuse_add(net, sk->sk_prot, -1); 462 sock_put(sk); 463 464 return 0; 465 } 466 467 static int raw_bind(struct socket *sock, struct sockaddr_unsized *uaddr, int len) 468 { 469 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; 470 struct sock *sk = sock->sk; 471 struct raw_sock *ro = raw_sk(sk); 472 struct net_device *dev = NULL; 473 int ifindex; 474 int err = 0; 475 int notify_enetdown = 0; 476 477 if (len < RAW_MIN_NAMELEN) 478 return -EINVAL; 479 if (addr->can_family != AF_CAN) 480 return -EINVAL; 481 482 rtnl_lock(); 483 lock_sock(sk); 484 485 if (ro->bound && addr->can_ifindex == ro->ifindex) 486 goto out; 487 488 if (addr->can_ifindex) { 489 dev = dev_get_by_index(sock_net(sk), addr->can_ifindex); 490 if (!dev) { 491 err = -ENODEV; 492 goto out; 493 } 494 if (dev->type != ARPHRD_CAN) { 495 err = -ENODEV; 496 goto out_put_dev; 497 } 498 499 if (!(dev->flags & IFF_UP)) 500 notify_enetdown = 1; 501 502 ifindex = dev->ifindex; 503 504 /* filters set by default/setsockopt */ 505 err = raw_enable_allfilters(sock_net(sk), dev, sk); 506 if (err) 507 goto out_put_dev; 508 509 } else { 510 ifindex = 0; 511 512 /* filters set by default/setsockopt */ 513 err = raw_enable_allfilters(sock_net(sk), NULL, sk); 514 } 515 516 if (!err) { 517 if (ro->bound) { 518 /* unregister old filters */ 519 if (ro->dev) { 520 raw_disable_allfilters(dev_net(ro->dev), 521 ro->dev, sk); 522 /* drop reference to old ro->dev */ 523 netdev_put(ro->dev, &ro->dev_tracker); 524 } else { 525 raw_disable_allfilters(sock_net(sk), NULL, sk); 526 } 527 } 528 ro->ifindex = ifindex; 529 ro->bound = 1; 530 /* bind() ok -> hold a reference for new ro->dev */ 531 ro->dev = dev; 532 if (ro->dev) 533 netdev_hold(ro->dev, &ro->dev_tracker, GFP_KERNEL); 534 } 535 536 out_put_dev: 537 /* remove potential reference from dev_get_by_index() */ 538 dev_put(dev); 539 out: 540 release_sock(sk); 541 rtnl_unlock(); 542 543 if (notify_enetdown) { 544 sk->sk_err = ENETDOWN; 545 if (!sock_flag(sk, SOCK_DEAD)) 546 sk_error_report(sk); 547 } 548 549 return err; 550 } 551 552 static int raw_getname(struct socket *sock, struct sockaddr *uaddr, 553 int peer) 554 { 555 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; 556 struct sock *sk = sock->sk; 557 struct raw_sock *ro = raw_sk(sk); 558 559 if (peer) 560 return -EOPNOTSUPP; 561 562 memset(addr, 0, RAW_MIN_NAMELEN); 563 addr->can_family = AF_CAN; 564 addr->can_ifindex = ro->ifindex; 565 566 return RAW_MIN_NAMELEN; 567 } 568 569 static int raw_setsockopt_locked(struct socket *sock, int optname, 570 sockptr_t optval, unsigned int optlen) 571 { 572 struct sock *sk = sock->sk; 573 struct raw_sock *ro = raw_sk(sk); 574 struct can_filter *filter = NULL; /* dyn. alloc'ed filters */ 575 struct can_filter sfilter; /* single filter */ 576 struct net_device *dev = NULL; 577 can_err_mask_t err_mask = 0; 578 int count = 0; 579 int flag; 580 int err = 0; 581 582 switch (optname) { 583 case CAN_RAW_FILTER: 584 if (optlen % sizeof(struct can_filter) != 0) 585 return -EINVAL; 586 587 if (optlen > CAN_RAW_FILTER_MAX * sizeof(struct can_filter)) 588 return -EINVAL; 589 590 count = optlen / sizeof(struct can_filter); 591 592 if (count > 1) { 593 /* filter does not fit into dfilter => alloc space */ 594 filter = memdup_sockptr(optval, optlen); 595 if (IS_ERR(filter)) 596 return PTR_ERR(filter); 597 } else if (count == 1) { 598 if (copy_from_sockptr(&sfilter, optval, sizeof(sfilter))) 599 return -EFAULT; 600 } 601 602 dev = ro->dev; 603 if (ro->bound && dev && dev->reg_state != NETREG_REGISTERED) { 604 if (count > 1) 605 kfree(filter); 606 return -ENODEV; 607 } 608 609 if (ro->bound) { 610 /* (try to) register the new filters */ 611 if (count == 1) 612 err = raw_enable_filters(sock_net(sk), dev, sk, 613 &sfilter, 1); 614 else 615 err = raw_enable_filters(sock_net(sk), dev, sk, 616 filter, count); 617 if (err) { 618 if (count > 1) 619 kfree(filter); 620 return err; 621 } 622 623 /* remove old filter registrations */ 624 raw_disable_filters(sock_net(sk), dev, sk, ro->filter, 625 ro->count); 626 } 627 628 /* remove old filter space */ 629 if (ro->count > 1) 630 kfree(ro->filter); 631 632 /* link new filters to the socket */ 633 if (count == 1) { 634 /* copy filter data for single filter */ 635 ro->dfilter = sfilter; 636 filter = &ro->dfilter; 637 } 638 ro->filter = filter; 639 ro->count = count; 640 break; 641 642 case CAN_RAW_ERR_FILTER: 643 if (optlen != sizeof(err_mask)) 644 return -EINVAL; 645 646 if (copy_from_sockptr(&err_mask, optval, optlen)) 647 return -EFAULT; 648 649 err_mask &= CAN_ERR_MASK; 650 651 dev = ro->dev; 652 if (ro->bound && dev && dev->reg_state != NETREG_REGISTERED) 653 return -ENODEV; 654 655 /* remove current error mask */ 656 if (ro->bound) { 657 /* (try to) register the new err_mask */ 658 err = raw_enable_errfilter(sock_net(sk), dev, sk, 659 err_mask); 660 661 if (err) 662 return err; 663 664 /* remove old err_mask registration */ 665 raw_disable_errfilter(sock_net(sk), dev, sk, 666 ro->err_mask); 667 } 668 669 /* link new err_mask to the socket */ 670 ro->err_mask = err_mask; 671 break; 672 673 case CAN_RAW_LOOPBACK: 674 if (optlen != sizeof(flag)) 675 return -EINVAL; 676 677 if (copy_from_sockptr(&flag, optval, optlen)) 678 return -EFAULT; 679 680 ro->loopback = !!flag; 681 break; 682 683 case CAN_RAW_RECV_OWN_MSGS: 684 if (optlen != sizeof(flag)) 685 return -EINVAL; 686 687 if (copy_from_sockptr(&flag, optval, optlen)) 688 return -EFAULT; 689 690 ro->recv_own_msgs = !!flag; 691 break; 692 693 case CAN_RAW_FD_FRAMES: 694 if (optlen != sizeof(flag)) 695 return -EINVAL; 696 697 if (copy_from_sockptr(&flag, optval, optlen)) 698 return -EFAULT; 699 700 /* Enabling CAN XL includes CAN FD */ 701 if (ro->xl_frames && !flag) 702 return -EINVAL; 703 704 ro->fd_frames = !!flag; 705 break; 706 707 case CAN_RAW_XL_FRAMES: 708 if (optlen != sizeof(flag)) 709 return -EINVAL; 710 711 if (copy_from_sockptr(&flag, optval, optlen)) 712 return -EFAULT; 713 714 ro->xl_frames = !!flag; 715 716 /* Enabling CAN XL includes CAN FD */ 717 if (ro->xl_frames) 718 ro->fd_frames = ro->xl_frames; 719 break; 720 721 case CAN_RAW_XL_VCID_OPTS: 722 if (optlen != sizeof(ro->raw_vcid_opts)) 723 return -EINVAL; 724 725 if (copy_from_sockptr(&ro->raw_vcid_opts, optval, optlen)) 726 return -EFAULT; 727 728 /* prepare 32 bit values for handling in hot path */ 729 ro->tx_vcid_shifted = ro->raw_vcid_opts.tx_vcid << CANXL_VCID_OFFSET; 730 ro->rx_vcid_shifted = ro->raw_vcid_opts.rx_vcid << CANXL_VCID_OFFSET; 731 ro->rx_vcid_mask_shifted = ro->raw_vcid_opts.rx_vcid_mask << CANXL_VCID_OFFSET; 732 break; 733 734 case CAN_RAW_JOIN_FILTERS: 735 if (optlen != sizeof(flag)) 736 return -EINVAL; 737 738 if (copy_from_sockptr(&flag, optval, optlen)) 739 return -EFAULT; 740 741 ro->join_filters = !!flag; 742 break; 743 744 default: 745 return -ENOPROTOOPT; 746 } 747 return err; 748 } 749 750 static int raw_setsockopt(struct socket *sock, int level, int optname, 751 sockptr_t optval, unsigned int optlen) 752 { 753 struct sock *sk = sock->sk; 754 int err; 755 756 if (level != SOL_CAN_RAW) 757 return -EINVAL; 758 759 rtnl_lock(); 760 lock_sock(sk); 761 762 err = raw_setsockopt_locked(sock, optname, optval, optlen); 763 764 release_sock(sk); 765 rtnl_unlock(); 766 767 return err; 768 } 769 770 static int raw_getsockopt(struct socket *sock, int level, int optname, 771 sockopt_t *opt) 772 { 773 struct sock *sk = sock->sk; 774 struct raw_sock *ro = raw_sk(sk); 775 int flag; 776 int len; 777 void *val; 778 779 if (level != SOL_CAN_RAW) 780 return -EINVAL; 781 len = opt->optlen; 782 if (len < 0) 783 return -EINVAL; 784 785 switch (optname) { 786 case CAN_RAW_FILTER: { 787 int err = 0; 788 789 lock_sock(sk); 790 if (ro->count > 0) { 791 int fsize = ro->count * sizeof(struct can_filter); 792 793 /* user space buffer to small for filter list? */ 794 if (len < fsize) { 795 /* return -ERANGE and needed space in optlen */ 796 err = -ERANGE; 797 opt->optlen = fsize; 798 } else { 799 if (len > fsize) 800 len = fsize; 801 if (copy_to_iter(ro->filter, len, 802 &opt->iter_out) != len) 803 err = -EFAULT; 804 } 805 } else { 806 len = 0; 807 } 808 release_sock(sk); 809 810 if (!err) 811 opt->optlen = len; 812 return err; 813 } 814 case CAN_RAW_ERR_FILTER: 815 if (len > sizeof(can_err_mask_t)) 816 len = sizeof(can_err_mask_t); 817 val = &ro->err_mask; 818 break; 819 820 case CAN_RAW_LOOPBACK: 821 if (len > sizeof(int)) 822 len = sizeof(int); 823 flag = ro->loopback; 824 val = &flag; 825 break; 826 827 case CAN_RAW_RECV_OWN_MSGS: 828 if (len > sizeof(int)) 829 len = sizeof(int); 830 flag = ro->recv_own_msgs; 831 val = &flag; 832 break; 833 834 case CAN_RAW_FD_FRAMES: 835 if (len > sizeof(int)) 836 len = sizeof(int); 837 flag = ro->fd_frames; 838 val = &flag; 839 break; 840 841 case CAN_RAW_XL_FRAMES: 842 if (len > sizeof(int)) 843 len = sizeof(int); 844 flag = ro->xl_frames; 845 val = &flag; 846 break; 847 848 case CAN_RAW_XL_VCID_OPTS: { 849 int err = 0; 850 851 /* user space buffer to small for VCID opts? */ 852 if (len < sizeof(ro->raw_vcid_opts)) { 853 /* return -ERANGE and needed space in optlen */ 854 err = -ERANGE; 855 opt->optlen = sizeof(ro->raw_vcid_opts); 856 } else { 857 if (len > sizeof(ro->raw_vcid_opts)) 858 len = sizeof(ro->raw_vcid_opts); 859 if (copy_to_iter(&ro->raw_vcid_opts, len, 860 &opt->iter_out) != len) 861 err = -EFAULT; 862 } 863 if (!err) 864 opt->optlen = len; 865 return err; 866 } 867 case CAN_RAW_JOIN_FILTERS: 868 if (len > sizeof(int)) 869 len = sizeof(int); 870 flag = ro->join_filters; 871 val = &flag; 872 break; 873 874 default: 875 return -ENOPROTOOPT; 876 } 877 878 opt->optlen = len; 879 if (copy_to_iter(val, len, &opt->iter_out) != len) 880 return -EFAULT; 881 return 0; 882 } 883 884 static void raw_put_canxl_vcid(struct raw_sock *ro, struct sk_buff *skb) 885 { 886 struct canxl_frame *cxl = (struct canxl_frame *)skb->data; 887 888 /* sanitize non CAN XL bits */ 889 cxl->prio &= (CANXL_PRIO_MASK | CANXL_VCID_MASK); 890 891 /* clear VCID in CAN XL frame if pass through is disabled */ 892 if (!(ro->raw_vcid_opts.flags & CAN_RAW_XL_VCID_TX_PASS)) 893 cxl->prio &= CANXL_PRIO_MASK; 894 895 /* set VCID in CAN XL frame if enabled */ 896 if (ro->raw_vcid_opts.flags & CAN_RAW_XL_VCID_TX_SET) { 897 cxl->prio &= CANXL_PRIO_MASK; 898 cxl->prio |= ro->tx_vcid_shifted; 899 } 900 } 901 902 static unsigned int raw_check_txframe(struct raw_sock *ro, struct sk_buff *skb, 903 struct net_device *dev) 904 { 905 /* Classical CAN */ 906 if (can_is_can_skb(skb) && can_cap_enabled(dev, CAN_CAP_CC)) 907 return CAN_MTU; 908 909 /* CAN FD */ 910 if (ro->fd_frames && can_is_canfd_skb(skb) && 911 can_cap_enabled(dev, CAN_CAP_FD)) 912 return CANFD_MTU; 913 914 /* CAN XL */ 915 if (ro->xl_frames && can_is_canxl_skb(skb) && 916 can_cap_enabled(dev, CAN_CAP_XL)) 917 return CANXL_MTU; 918 919 return 0; 920 } 921 922 static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) 923 { 924 struct sock *sk = sock->sk; 925 struct raw_sock *ro = raw_sk(sk); 926 struct sockcm_cookie sockc; 927 struct sk_buff *skb; 928 struct can_skb_ext *csx; 929 struct net_device *dev; 930 unsigned int txmtu; 931 int ifindex; 932 int err = -EINVAL; 933 934 /* check for valid CAN frame sizes */ 935 if (size < CANXL_HDR_SIZE + CANXL_MIN_DLEN || size > CANXL_MTU) 936 return -EINVAL; 937 938 if (msg->msg_name) { 939 DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name); 940 941 if (msg->msg_namelen < RAW_MIN_NAMELEN) 942 return -EINVAL; 943 944 if (addr->can_family != AF_CAN) 945 return -EINVAL; 946 947 ifindex = addr->can_ifindex; 948 } else { 949 ifindex = ro->ifindex; 950 } 951 952 dev = dev_get_by_index(sock_net(sk), ifindex); 953 if (!dev) 954 return -ENXIO; 955 956 /* no sending on a CAN device in read-only mode */ 957 if (can_cap_enabled(dev, CAN_CAP_RO)) { 958 err = -EACCES; 959 goto put_dev; 960 } 961 962 skb = sock_alloc_send_skb(sk, size, msg->msg_flags & MSG_DONTWAIT, 963 &err); 964 if (!skb) 965 goto put_dev; 966 967 csx = can_skb_ext_add(skb); 968 if (!csx) { 969 kfree_skb(skb); 970 err = -ENOMEM; 971 goto put_dev; 972 } 973 974 csx->can_iif = dev->ifindex; 975 976 /* fill the skb before testing for valid CAN frames */ 977 err = memcpy_from_msg(skb_put(skb, size), msg, size); 978 if (err < 0) 979 goto free_skb; 980 981 err = -EINVAL; 982 983 /* check for valid CAN (CC/FD/XL) frame content */ 984 txmtu = raw_check_txframe(ro, skb, dev); 985 if (!txmtu) 986 goto free_skb; 987 988 /* only CANXL: clear/forward/set VCID value */ 989 if (txmtu == CANXL_MTU) 990 raw_put_canxl_vcid(ro, skb); 991 992 sockcm_init(&sockc, sk); 993 if (msg->msg_controllen) { 994 err = sock_cmsg_send(sk, msg, &sockc); 995 if (unlikely(err)) 996 goto free_skb; 997 } 998 999 skb->dev = dev; 1000 skb->priority = sockc.priority; 1001 skb->mark = sockc.mark; 1002 skb->tstamp = sockc.transmit_time; 1003 1004 skb_setup_tx_timestamp(skb, &sockc); 1005 1006 err = can_send(skb, ro->loopback); 1007 1008 dev_put(dev); 1009 1010 if (err) 1011 goto send_failed; 1012 1013 return size; 1014 1015 free_skb: 1016 kfree_skb(skb); 1017 put_dev: 1018 dev_put(dev); 1019 send_failed: 1020 return err; 1021 } 1022 1023 static int raw_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 1024 int flags) 1025 { 1026 struct sock *sk = sock->sk; 1027 struct sk_buff *skb; 1028 int err = 0; 1029 1030 if (flags & MSG_ERRQUEUE) 1031 return sock_recv_errqueue(sk, msg, size, 1032 SOL_CAN_RAW, SCM_CAN_RAW_ERRQUEUE); 1033 1034 skb = skb_recv_datagram(sk, flags, &err); 1035 if (!skb) 1036 return err; 1037 1038 if (size < skb->len) 1039 msg->msg_flags |= MSG_TRUNC; 1040 else 1041 size = skb->len; 1042 1043 err = memcpy_to_msg(msg, skb->data, size); 1044 if (err < 0) { 1045 skb_free_datagram(sk, skb); 1046 return err; 1047 } 1048 1049 sock_recv_cmsgs(msg, sk, skb); 1050 1051 if (msg->msg_name) { 1052 __sockaddr_check_size(RAW_MIN_NAMELEN); 1053 msg->msg_namelen = RAW_MIN_NAMELEN; 1054 memcpy(msg->msg_name, skb->cb, msg->msg_namelen); 1055 } 1056 1057 /* assign the flags that have been recorded in raw_rcv() */ 1058 msg->msg_flags |= *(raw_flags(skb)); 1059 1060 skb_free_datagram(sk, skb); 1061 1062 return size; 1063 } 1064 1065 static int raw_sock_no_ioctlcmd(struct socket *sock, unsigned int cmd, 1066 unsigned long arg) 1067 { 1068 /* no ioctls for socket layer -> hand it down to NIC layer */ 1069 return -ENOIOCTLCMD; 1070 } 1071 1072 static const struct proto_ops raw_ops = { 1073 .family = PF_CAN, 1074 .release = raw_release, 1075 .bind = raw_bind, 1076 .connect = sock_no_connect, 1077 .socketpair = sock_no_socketpair, 1078 .accept = sock_no_accept, 1079 .getname = raw_getname, 1080 .poll = datagram_poll, 1081 .ioctl = raw_sock_no_ioctlcmd, 1082 .gettstamp = sock_gettstamp, 1083 .listen = sock_no_listen, 1084 .shutdown = sock_no_shutdown, 1085 .setsockopt = raw_setsockopt, 1086 .getsockopt_iter = raw_getsockopt, 1087 .sendmsg = raw_sendmsg, 1088 .recvmsg = raw_recvmsg, 1089 .mmap = sock_no_mmap, 1090 }; 1091 1092 static struct proto raw_proto __read_mostly = { 1093 .name = "CAN_RAW", 1094 .owner = THIS_MODULE, 1095 .obj_size = sizeof(struct raw_sock), 1096 .init = raw_init, 1097 }; 1098 1099 static const struct can_proto raw_can_proto = { 1100 .type = SOCK_RAW, 1101 .protocol = CAN_RAW, 1102 .ops = &raw_ops, 1103 .prot = &raw_proto, 1104 }; 1105 1106 static struct notifier_block canraw_notifier = { 1107 .notifier_call = raw_notifier 1108 }; 1109 1110 static __init int raw_module_init(void) 1111 { 1112 int err; 1113 1114 pr_info("can: raw protocol\n"); 1115 1116 err = register_netdevice_notifier(&canraw_notifier); 1117 if (err) 1118 return err; 1119 1120 err = can_proto_register(&raw_can_proto); 1121 if (err < 0) { 1122 pr_err("can: registration of raw protocol failed\n"); 1123 goto register_proto_failed; 1124 } 1125 1126 return 0; 1127 1128 register_proto_failed: 1129 unregister_netdevice_notifier(&canraw_notifier); 1130 return err; 1131 } 1132 1133 static __exit void raw_module_exit(void) 1134 { 1135 can_proto_unregister(&raw_can_proto); 1136 unregister_netdevice_notifier(&canraw_notifier); 1137 } 1138 1139 module_init(raw_module_init); 1140 module_exit(raw_module_exit); 1141