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_locked(struct socket *sock, 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 switch (optname) { 579 case CAN_RAW_FILTER: 580 if (optlen % sizeof(struct can_filter) != 0) 581 return -EINVAL; 582 583 if (optlen > CAN_RAW_FILTER_MAX * sizeof(struct can_filter)) 584 return -EINVAL; 585 586 count = optlen / sizeof(struct can_filter); 587 588 if (count > 1) { 589 /* filter does not fit into dfilter => alloc space */ 590 filter = memdup_sockptr(optval, optlen); 591 if (IS_ERR(filter)) 592 return PTR_ERR(filter); 593 } else if (count == 1) { 594 if (copy_from_sockptr(&sfilter, optval, sizeof(sfilter))) 595 return -EFAULT; 596 } 597 598 dev = ro->dev; 599 if (ro->bound && dev && dev->reg_state != NETREG_REGISTERED) { 600 if (count > 1) 601 kfree(filter); 602 return -ENODEV; 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 return err; 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 break; 637 638 case CAN_RAW_ERR_FILTER: 639 if (optlen != sizeof(err_mask)) 640 return -EINVAL; 641 642 if (copy_from_sockptr(&err_mask, optval, optlen)) 643 return -EFAULT; 644 645 err_mask &= CAN_ERR_MASK; 646 647 dev = ro->dev; 648 if (ro->bound && dev && dev->reg_state != NETREG_REGISTERED) 649 return -ENODEV; 650 651 /* remove current error mask */ 652 if (ro->bound) { 653 /* (try to) register the new err_mask */ 654 err = raw_enable_errfilter(sock_net(sk), dev, sk, 655 err_mask); 656 657 if (err) 658 return err; 659 660 /* remove old err_mask registration */ 661 raw_disable_errfilter(sock_net(sk), dev, sk, 662 ro->err_mask); 663 } 664 665 /* link new err_mask to the socket */ 666 ro->err_mask = err_mask; 667 break; 668 669 case CAN_RAW_LOOPBACK: 670 if (optlen != sizeof(flag)) 671 return -EINVAL; 672 673 if (copy_from_sockptr(&flag, optval, optlen)) 674 return -EFAULT; 675 676 ro->loopback = !!flag; 677 break; 678 679 case CAN_RAW_RECV_OWN_MSGS: 680 if (optlen != sizeof(flag)) 681 return -EINVAL; 682 683 if (copy_from_sockptr(&flag, optval, optlen)) 684 return -EFAULT; 685 686 ro->recv_own_msgs = !!flag; 687 break; 688 689 case CAN_RAW_FD_FRAMES: 690 if (optlen != sizeof(flag)) 691 return -EINVAL; 692 693 if (copy_from_sockptr(&flag, optval, optlen)) 694 return -EFAULT; 695 696 /* Enabling CAN XL includes CAN FD */ 697 if (ro->xl_frames && !flag) 698 return -EINVAL; 699 700 ro->fd_frames = !!flag; 701 break; 702 703 case CAN_RAW_XL_FRAMES: 704 if (optlen != sizeof(flag)) 705 return -EINVAL; 706 707 if (copy_from_sockptr(&flag, optval, optlen)) 708 return -EFAULT; 709 710 ro->xl_frames = !!flag; 711 712 /* Enabling CAN XL includes CAN FD */ 713 if (ro->xl_frames) 714 ro->fd_frames = ro->xl_frames; 715 break; 716 717 case CAN_RAW_XL_VCID_OPTS: 718 if (optlen != sizeof(ro->raw_vcid_opts)) 719 return -EINVAL; 720 721 if (copy_from_sockptr(&ro->raw_vcid_opts, optval, optlen)) 722 return -EFAULT; 723 724 /* prepare 32 bit values for handling in hot path */ 725 ro->tx_vcid_shifted = ro->raw_vcid_opts.tx_vcid << CANXL_VCID_OFFSET; 726 ro->rx_vcid_shifted = ro->raw_vcid_opts.rx_vcid << CANXL_VCID_OFFSET; 727 ro->rx_vcid_mask_shifted = ro->raw_vcid_opts.rx_vcid_mask << CANXL_VCID_OFFSET; 728 break; 729 730 case CAN_RAW_JOIN_FILTERS: 731 if (optlen != sizeof(flag)) 732 return -EINVAL; 733 734 if (copy_from_sockptr(&flag, optval, optlen)) 735 return -EFAULT; 736 737 ro->join_filters = !!flag; 738 break; 739 740 default: 741 return -ENOPROTOOPT; 742 } 743 return err; 744 } 745 746 static int raw_setsockopt(struct socket *sock, int level, int optname, 747 sockptr_t optval, unsigned int optlen) 748 { 749 struct sock *sk = sock->sk; 750 int err; 751 752 if (level != SOL_CAN_RAW) 753 return -EINVAL; 754 755 rtnl_lock(); 756 lock_sock(sk); 757 758 err = raw_setsockopt_locked(sock, optname, optval, optlen); 759 760 release_sock(sk); 761 rtnl_unlock(); 762 763 return err; 764 } 765 766 static int raw_getsockopt(struct socket *sock, int level, int optname, 767 sockopt_t *opt) 768 { 769 struct sock *sk = sock->sk; 770 struct raw_sock *ro = raw_sk(sk); 771 int flag; 772 int len; 773 void *val; 774 775 if (level != SOL_CAN_RAW) 776 return -EINVAL; 777 len = opt->optlen; 778 if (len < 0) 779 return -EINVAL; 780 781 switch (optname) { 782 case CAN_RAW_FILTER: { 783 int err = 0; 784 785 lock_sock(sk); 786 if (ro->count > 0) { 787 int fsize = ro->count * sizeof(struct can_filter); 788 789 /* user space buffer to small for filter list? */ 790 if (len < fsize) { 791 /* return -ERANGE and needed space in optlen */ 792 err = -ERANGE; 793 opt->optlen = fsize; 794 } else { 795 if (len > fsize) 796 len = fsize; 797 if (copy_to_iter(ro->filter, len, 798 &opt->iter_out) != len) 799 err = -EFAULT; 800 } 801 } else { 802 len = 0; 803 } 804 release_sock(sk); 805 806 if (!err) 807 opt->optlen = len; 808 return err; 809 } 810 case CAN_RAW_ERR_FILTER: 811 if (len > sizeof(can_err_mask_t)) 812 len = sizeof(can_err_mask_t); 813 val = &ro->err_mask; 814 break; 815 816 case CAN_RAW_LOOPBACK: 817 if (len > sizeof(int)) 818 len = sizeof(int); 819 flag = ro->loopback; 820 val = &flag; 821 break; 822 823 case CAN_RAW_RECV_OWN_MSGS: 824 if (len > sizeof(int)) 825 len = sizeof(int); 826 flag = ro->recv_own_msgs; 827 val = &flag; 828 break; 829 830 case CAN_RAW_FD_FRAMES: 831 if (len > sizeof(int)) 832 len = sizeof(int); 833 flag = ro->fd_frames; 834 val = &flag; 835 break; 836 837 case CAN_RAW_XL_FRAMES: 838 if (len > sizeof(int)) 839 len = sizeof(int); 840 flag = ro->xl_frames; 841 val = &flag; 842 break; 843 844 case CAN_RAW_XL_VCID_OPTS: { 845 int err = 0; 846 847 /* user space buffer to small for VCID opts? */ 848 if (len < sizeof(ro->raw_vcid_opts)) { 849 /* return -ERANGE and needed space in optlen */ 850 err = -ERANGE; 851 opt->optlen = sizeof(ro->raw_vcid_opts); 852 } else { 853 if (len > sizeof(ro->raw_vcid_opts)) 854 len = sizeof(ro->raw_vcid_opts); 855 if (copy_to_iter(&ro->raw_vcid_opts, len, 856 &opt->iter_out) != len) 857 err = -EFAULT; 858 } 859 if (!err) 860 opt->optlen = len; 861 return err; 862 } 863 case CAN_RAW_JOIN_FILTERS: 864 if (len > sizeof(int)) 865 len = sizeof(int); 866 flag = ro->join_filters; 867 val = &flag; 868 break; 869 870 default: 871 return -ENOPROTOOPT; 872 } 873 874 opt->optlen = len; 875 if (copy_to_iter(val, len, &opt->iter_out) != len) 876 return -EFAULT; 877 return 0; 878 } 879 880 static void raw_put_canxl_vcid(struct raw_sock *ro, struct sk_buff *skb) 881 { 882 struct canxl_frame *cxl = (struct canxl_frame *)skb->data; 883 884 /* sanitize non CAN XL bits */ 885 cxl->prio &= (CANXL_PRIO_MASK | CANXL_VCID_MASK); 886 887 /* clear VCID in CAN XL frame if pass through is disabled */ 888 if (!(ro->raw_vcid_opts.flags & CAN_RAW_XL_VCID_TX_PASS)) 889 cxl->prio &= CANXL_PRIO_MASK; 890 891 /* set VCID in CAN XL frame if enabled */ 892 if (ro->raw_vcid_opts.flags & CAN_RAW_XL_VCID_TX_SET) { 893 cxl->prio &= CANXL_PRIO_MASK; 894 cxl->prio |= ro->tx_vcid_shifted; 895 } 896 } 897 898 static unsigned int raw_check_txframe(struct raw_sock *ro, struct sk_buff *skb, 899 struct net_device *dev) 900 { 901 /* Classical CAN */ 902 if (can_is_can_skb(skb) && can_cap_enabled(dev, CAN_CAP_CC)) 903 return CAN_MTU; 904 905 /* CAN FD */ 906 if (ro->fd_frames && can_is_canfd_skb(skb) && 907 can_cap_enabled(dev, CAN_CAP_FD)) 908 return CANFD_MTU; 909 910 /* CAN XL */ 911 if (ro->xl_frames && can_is_canxl_skb(skb) && 912 can_cap_enabled(dev, CAN_CAP_XL)) 913 return CANXL_MTU; 914 915 return 0; 916 } 917 918 static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) 919 { 920 struct sock *sk = sock->sk; 921 struct raw_sock *ro = raw_sk(sk); 922 struct sockcm_cookie sockc; 923 struct sk_buff *skb; 924 struct can_skb_ext *csx; 925 struct net_device *dev; 926 unsigned int txmtu; 927 int ifindex; 928 int err = -EINVAL; 929 930 /* check for valid CAN frame sizes */ 931 if (size < CANXL_HDR_SIZE + CANXL_MIN_DLEN || size > CANXL_MTU) 932 return -EINVAL; 933 934 if (msg->msg_name) { 935 DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name); 936 937 if (msg->msg_namelen < RAW_MIN_NAMELEN) 938 return -EINVAL; 939 940 if (addr->can_family != AF_CAN) 941 return -EINVAL; 942 943 ifindex = addr->can_ifindex; 944 } else { 945 ifindex = ro->ifindex; 946 } 947 948 dev = dev_get_by_index(sock_net(sk), ifindex); 949 if (!dev) 950 return -ENXIO; 951 952 /* no sending on a CAN device in read-only mode */ 953 if (can_cap_enabled(dev, CAN_CAP_RO)) { 954 err = -EACCES; 955 goto put_dev; 956 } 957 958 skb = sock_alloc_send_skb(sk, size, msg->msg_flags & MSG_DONTWAIT, 959 &err); 960 if (!skb) 961 goto put_dev; 962 963 csx = can_skb_ext_add(skb); 964 if (!csx) { 965 kfree_skb(skb); 966 err = -ENOMEM; 967 goto put_dev; 968 } 969 970 csx->can_iif = dev->ifindex; 971 972 /* fill the skb before testing for valid CAN frames */ 973 err = memcpy_from_msg(skb_put(skb, size), msg, size); 974 if (err < 0) 975 goto free_skb; 976 977 err = -EINVAL; 978 979 /* check for valid CAN (CC/FD/XL) frame content */ 980 txmtu = raw_check_txframe(ro, skb, dev); 981 if (!txmtu) 982 goto free_skb; 983 984 /* only CANXL: clear/forward/set VCID value */ 985 if (txmtu == CANXL_MTU) 986 raw_put_canxl_vcid(ro, skb); 987 988 sockcm_init(&sockc, sk); 989 if (msg->msg_controllen) { 990 err = sock_cmsg_send(sk, msg, &sockc); 991 if (unlikely(err)) 992 goto free_skb; 993 } 994 995 skb->dev = dev; 996 skb->priority = sockc.priority; 997 skb->mark = sockc.mark; 998 skb->tstamp = sockc.transmit_time; 999 1000 skb_setup_tx_timestamp(skb, &sockc); 1001 1002 err = can_send(skb, ro->loopback); 1003 1004 dev_put(dev); 1005 1006 if (err) 1007 goto send_failed; 1008 1009 return size; 1010 1011 free_skb: 1012 kfree_skb(skb); 1013 put_dev: 1014 dev_put(dev); 1015 send_failed: 1016 return err; 1017 } 1018 1019 static int raw_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 1020 int flags) 1021 { 1022 struct sock *sk = sock->sk; 1023 struct sk_buff *skb; 1024 int err = 0; 1025 1026 if (flags & MSG_ERRQUEUE) 1027 return sock_recv_errqueue(sk, msg, size, 1028 SOL_CAN_RAW, SCM_CAN_RAW_ERRQUEUE); 1029 1030 skb = skb_recv_datagram(sk, flags, &err); 1031 if (!skb) 1032 return err; 1033 1034 if (size < skb->len) 1035 msg->msg_flags |= MSG_TRUNC; 1036 else 1037 size = skb->len; 1038 1039 err = memcpy_to_msg(msg, skb->data, size); 1040 if (err < 0) { 1041 skb_free_datagram(sk, skb); 1042 return err; 1043 } 1044 1045 sock_recv_cmsgs(msg, sk, skb); 1046 1047 if (msg->msg_name) { 1048 __sockaddr_check_size(RAW_MIN_NAMELEN); 1049 msg->msg_namelen = RAW_MIN_NAMELEN; 1050 memcpy(msg->msg_name, skb->cb, msg->msg_namelen); 1051 } 1052 1053 /* assign the flags that have been recorded in raw_rcv() */ 1054 msg->msg_flags |= *(raw_flags(skb)); 1055 1056 skb_free_datagram(sk, skb); 1057 1058 return size; 1059 } 1060 1061 static int raw_sock_no_ioctlcmd(struct socket *sock, unsigned int cmd, 1062 unsigned long arg) 1063 { 1064 /* no ioctls for socket layer -> hand it down to NIC layer */ 1065 return -ENOIOCTLCMD; 1066 } 1067 1068 static const struct proto_ops raw_ops = { 1069 .family = PF_CAN, 1070 .release = raw_release, 1071 .bind = raw_bind, 1072 .connect = sock_no_connect, 1073 .socketpair = sock_no_socketpair, 1074 .accept = sock_no_accept, 1075 .getname = raw_getname, 1076 .poll = datagram_poll, 1077 .ioctl = raw_sock_no_ioctlcmd, 1078 .gettstamp = sock_gettstamp, 1079 .listen = sock_no_listen, 1080 .shutdown = sock_no_shutdown, 1081 .setsockopt = raw_setsockopt, 1082 .getsockopt_iter = raw_getsockopt, 1083 .sendmsg = raw_sendmsg, 1084 .recvmsg = raw_recvmsg, 1085 .mmap = sock_no_mmap, 1086 }; 1087 1088 static struct proto raw_proto __read_mostly = { 1089 .name = "CAN_RAW", 1090 .owner = THIS_MODULE, 1091 .obj_size = sizeof(struct raw_sock), 1092 .init = raw_init, 1093 }; 1094 1095 static const struct can_proto raw_can_proto = { 1096 .type = SOCK_RAW, 1097 .protocol = CAN_RAW, 1098 .ops = &raw_ops, 1099 .prot = &raw_proto, 1100 }; 1101 1102 static struct notifier_block canraw_notifier = { 1103 .notifier_call = raw_notifier 1104 }; 1105 1106 static __init int raw_module_init(void) 1107 { 1108 int err; 1109 1110 pr_info("can: raw protocol\n"); 1111 1112 err = register_netdevice_notifier(&canraw_notifier); 1113 if (err) 1114 return err; 1115 1116 err = can_proto_register(&raw_can_proto); 1117 if (err < 0) { 1118 pr_err("can: registration of raw protocol failed\n"); 1119 goto register_proto_failed; 1120 } 1121 1122 return 0; 1123 1124 register_proto_failed: 1125 unregister_netdevice_notifier(&canraw_notifier); 1126 return err; 1127 } 1128 1129 static __exit void raw_module_exit(void) 1130 { 1131 can_proto_unregister(&raw_can_proto); 1132 unregister_netdevice_notifier(&canraw_notifier); 1133 } 1134 1135 module_init(raw_module_init); 1136 module_exit(raw_module_exit); 1137