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