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/core.h> 53 #include <linux/can/dev.h> /* for can_is_canxl_dev_mtu() */ 54 #include <linux/can/skb.h> 55 #include <linux/can/raw.h> 56 #include <net/sock.h> 57 #include <net/net_namespace.h> 58 59 MODULE_DESCRIPTION("PF_CAN raw protocol"); 60 MODULE_LICENSE("Dual BSD/GPL"); 61 MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>"); 62 MODULE_ALIAS("can-proto-1"); 63 64 #define RAW_MIN_NAMELEN CAN_REQUIRED_SIZE(struct sockaddr_can, can_ifindex) 65 66 #define MASK_ALL 0 67 68 /* A raw socket has a list of can_filters attached to it, each receiving 69 * the CAN frames matching that filter. If the filter list is empty, 70 * no CAN frames will be received by the socket. The default after 71 * opening the socket, is to have one filter which receives all frames. 72 * The filter list is allocated dynamically with the exception of the 73 * list containing only one item. This common case is optimized by 74 * storing the single filter in dfilter, to avoid using dynamic memory. 75 */ 76 77 struct uniqframe { 78 int skbcnt; 79 const struct sk_buff *skb; 80 unsigned int join_rx_count; 81 }; 82 83 struct raw_sock { 84 struct sock sk; 85 int bound; 86 int ifindex; 87 struct net_device *dev; 88 netdevice_tracker dev_tracker; 89 struct list_head notifier; 90 int loopback; 91 int recv_own_msgs; 92 int fd_frames; 93 int xl_frames; 94 struct can_raw_vcid_options raw_vcid_opts; 95 canid_t tx_vcid_shifted; 96 canid_t rx_vcid_shifted; 97 canid_t rx_vcid_mask_shifted; 98 int join_filters; 99 int count; /* number of active filters */ 100 struct can_filter dfilter; /* default/single filter */ 101 struct can_filter *filter; /* pointer to filter(s) */ 102 can_err_mask_t err_mask; 103 struct uniqframe __percpu *uniq; 104 }; 105 106 static LIST_HEAD(raw_notifier_list); 107 static DEFINE_SPINLOCK(raw_notifier_lock); 108 static struct raw_sock *raw_busy_notifier; 109 110 /* Return pointer to store the extra msg flags for raw_recvmsg(). 111 * We use the space of one unsigned int beyond the 'struct sockaddr_can' 112 * in skb->cb. 113 */ 114 static inline unsigned int *raw_flags(struct sk_buff *skb) 115 { 116 sock_skb_cb_check_size(sizeof(struct sockaddr_can) + 117 sizeof(unsigned int)); 118 119 /* return pointer after struct sockaddr_can */ 120 return (unsigned int *)(&((struct sockaddr_can *)skb->cb)[1]); 121 } 122 123 static inline struct raw_sock *raw_sk(const struct sock *sk) 124 { 125 return (struct raw_sock *)sk; 126 } 127 128 static void raw_rcv(struct sk_buff *oskb, void *data) 129 { 130 struct sock *sk = (struct sock *)data; 131 struct raw_sock *ro = raw_sk(sk); 132 enum skb_drop_reason reason; 133 struct sockaddr_can *addr; 134 struct sk_buff *skb; 135 unsigned int *pflags; 136 137 /* check the received tx sock reference */ 138 if (!ro->recv_own_msgs && oskb->sk == sk) 139 return; 140 141 /* make sure to not pass oversized frames to the socket */ 142 if (!ro->fd_frames && can_is_canfd_skb(oskb)) 143 return; 144 145 if (can_is_canxl_skb(oskb)) { 146 struct canxl_frame *cxl = (struct canxl_frame *)oskb->data; 147 148 /* make sure to not pass oversized frames to the socket */ 149 if (!ro->xl_frames) 150 return; 151 152 /* filter CAN XL VCID content */ 153 if (ro->raw_vcid_opts.flags & CAN_RAW_XL_VCID_RX_FILTER) { 154 /* apply VCID filter if user enabled the filter */ 155 if ((cxl->prio & ro->rx_vcid_mask_shifted) != 156 (ro->rx_vcid_shifted & ro->rx_vcid_mask_shifted)) 157 return; 158 } else { 159 /* no filter => do not forward VCID tagged frames */ 160 if (cxl->prio & CANXL_VCID_MASK) 161 return; 162 } 163 } 164 165 /* eliminate multiple filter matches for the same skb */ 166 if (this_cpu_ptr(ro->uniq)->skb == oskb && 167 this_cpu_ptr(ro->uniq)->skbcnt == can_skb_prv(oskb)->skbcnt) { 168 if (!ro->join_filters) 169 return; 170 171 this_cpu_inc(ro->uniq->join_rx_count); 172 /* drop frame until all enabled filters matched */ 173 if (this_cpu_ptr(ro->uniq)->join_rx_count < ro->count) 174 return; 175 } else { 176 this_cpu_ptr(ro->uniq)->skb = oskb; 177 this_cpu_ptr(ro->uniq)->skbcnt = can_skb_prv(oskb)->skbcnt; 178 this_cpu_ptr(ro->uniq)->join_rx_count = 1; 179 /* drop first frame to check all enabled filters? */ 180 if (ro->join_filters && ro->count > 1) 181 return; 182 } 183 184 /* clone the given skb to be able to enqueue it into the rcv queue */ 185 skb = skb_clone(oskb, GFP_ATOMIC); 186 if (!skb) 187 return; 188 189 /* Put the datagram to the queue so that raw_recvmsg() can get 190 * it from there. We need to pass the interface index to 191 * raw_recvmsg(). We pass a whole struct sockaddr_can in 192 * skb->cb containing the interface index. 193 */ 194 195 sock_skb_cb_check_size(sizeof(struct sockaddr_can)); 196 addr = (struct sockaddr_can *)skb->cb; 197 memset(addr, 0, sizeof(*addr)); 198 addr->can_family = AF_CAN; 199 addr->can_ifindex = skb->dev->ifindex; 200 201 /* add CAN specific message flags for raw_recvmsg() */ 202 pflags = raw_flags(skb); 203 *pflags = 0; 204 if (oskb->sk) 205 *pflags |= MSG_DONTROUTE; 206 if (oskb->sk == sk) 207 *pflags |= MSG_CONFIRM; 208 209 if (sock_queue_rcv_skb_reason(sk, skb, &reason) < 0) 210 sk_skb_reason_drop(sk, skb, reason); 211 } 212 213 static int raw_enable_filters(struct net *net, struct net_device *dev, 214 struct sock *sk, struct can_filter *filter, 215 int count) 216 { 217 int err = 0; 218 int i; 219 220 for (i = 0; i < count; i++) { 221 err = can_rx_register(net, dev, filter[i].can_id, 222 filter[i].can_mask, 223 raw_rcv, sk, "raw", sk); 224 if (err) { 225 /* clean up successfully registered filters */ 226 while (--i >= 0) 227 can_rx_unregister(net, dev, filter[i].can_id, 228 filter[i].can_mask, 229 raw_rcv, sk); 230 break; 231 } 232 } 233 234 return err; 235 } 236 237 static int raw_enable_errfilter(struct net *net, struct net_device *dev, 238 struct sock *sk, can_err_mask_t err_mask) 239 { 240 int err = 0; 241 242 if (err_mask) 243 err = can_rx_register(net, dev, 0, err_mask | CAN_ERR_FLAG, 244 raw_rcv, sk, "raw", sk); 245 246 return err; 247 } 248 249 static void raw_disable_filters(struct net *net, struct net_device *dev, 250 struct sock *sk, struct can_filter *filter, 251 int count) 252 { 253 int i; 254 255 for (i = 0; i < count; i++) 256 can_rx_unregister(net, dev, filter[i].can_id, 257 filter[i].can_mask, raw_rcv, sk); 258 } 259 260 static inline void raw_disable_errfilter(struct net *net, 261 struct net_device *dev, 262 struct sock *sk, 263 can_err_mask_t err_mask) 264 265 { 266 if (err_mask) 267 can_rx_unregister(net, dev, 0, err_mask | CAN_ERR_FLAG, 268 raw_rcv, sk); 269 } 270 271 static inline void raw_disable_allfilters(struct net *net, 272 struct net_device *dev, 273 struct sock *sk) 274 { 275 struct raw_sock *ro = raw_sk(sk); 276 277 raw_disable_filters(net, dev, sk, ro->filter, ro->count); 278 raw_disable_errfilter(net, dev, sk, ro->err_mask); 279 } 280 281 static int raw_enable_allfilters(struct net *net, struct net_device *dev, 282 struct sock *sk) 283 { 284 struct raw_sock *ro = raw_sk(sk); 285 int err; 286 287 err = raw_enable_filters(net, dev, sk, ro->filter, ro->count); 288 if (!err) { 289 err = raw_enable_errfilter(net, dev, sk, ro->err_mask); 290 if (err) 291 raw_disable_filters(net, dev, sk, ro->filter, 292 ro->count); 293 } 294 295 return err; 296 } 297 298 static void raw_notify(struct raw_sock *ro, unsigned long msg, 299 struct net_device *dev) 300 { 301 struct sock *sk = &ro->sk; 302 303 if (!net_eq(dev_net(dev), sock_net(sk))) 304 return; 305 306 if (ro->dev != dev) 307 return; 308 309 switch (msg) { 310 case NETDEV_UNREGISTER: 311 lock_sock(sk); 312 /* remove current filters & unregister */ 313 if (ro->bound) { 314 raw_disable_allfilters(dev_net(dev), dev, sk); 315 netdev_put(dev, &ro->dev_tracker); 316 } 317 318 if (ro->count > 1) 319 kfree(ro->filter); 320 321 ro->ifindex = 0; 322 ro->bound = 0; 323 ro->dev = NULL; 324 ro->count = 0; 325 release_sock(sk); 326 327 sk->sk_err = ENODEV; 328 if (!sock_flag(sk, SOCK_DEAD)) 329 sk_error_report(sk); 330 break; 331 332 case NETDEV_DOWN: 333 sk->sk_err = ENETDOWN; 334 if (!sock_flag(sk, SOCK_DEAD)) 335 sk_error_report(sk); 336 break; 337 } 338 } 339 340 static int raw_notifier(struct notifier_block *nb, unsigned long msg, 341 void *ptr) 342 { 343 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 344 345 if (dev->type != ARPHRD_CAN) 346 return NOTIFY_DONE; 347 if (msg != NETDEV_UNREGISTER && msg != NETDEV_DOWN) 348 return NOTIFY_DONE; 349 if (unlikely(raw_busy_notifier)) /* Check for reentrant bug. */ 350 return NOTIFY_DONE; 351 352 spin_lock(&raw_notifier_lock); 353 list_for_each_entry(raw_busy_notifier, &raw_notifier_list, notifier) { 354 spin_unlock(&raw_notifier_lock); 355 raw_notify(raw_busy_notifier, msg, dev); 356 spin_lock(&raw_notifier_lock); 357 } 358 raw_busy_notifier = NULL; 359 spin_unlock(&raw_notifier_lock); 360 return NOTIFY_DONE; 361 } 362 363 static int raw_init(struct sock *sk) 364 { 365 struct raw_sock *ro = raw_sk(sk); 366 367 ro->bound = 0; 368 ro->ifindex = 0; 369 ro->dev = NULL; 370 371 /* set default filter to single entry dfilter */ 372 ro->dfilter.can_id = 0; 373 ro->dfilter.can_mask = MASK_ALL; 374 ro->filter = &ro->dfilter; 375 ro->count = 1; 376 377 /* set default loopback behaviour */ 378 ro->loopback = 1; 379 ro->recv_own_msgs = 0; 380 ro->fd_frames = 0; 381 ro->xl_frames = 0; 382 ro->join_filters = 0; 383 384 /* alloc_percpu provides zero'ed memory */ 385 ro->uniq = alloc_percpu(struct uniqframe); 386 if (unlikely(!ro->uniq)) 387 return -ENOMEM; 388 389 /* set notifier */ 390 spin_lock(&raw_notifier_lock); 391 list_add_tail(&ro->notifier, &raw_notifier_list); 392 spin_unlock(&raw_notifier_lock); 393 394 return 0; 395 } 396 397 static int raw_release(struct socket *sock) 398 { 399 struct sock *sk = sock->sk; 400 struct raw_sock *ro; 401 struct net *net; 402 403 if (!sk) 404 return 0; 405 406 ro = raw_sk(sk); 407 net = sock_net(sk); 408 409 spin_lock(&raw_notifier_lock); 410 while (raw_busy_notifier == ro) { 411 spin_unlock(&raw_notifier_lock); 412 schedule_timeout_uninterruptible(1); 413 spin_lock(&raw_notifier_lock); 414 } 415 list_del(&ro->notifier); 416 spin_unlock(&raw_notifier_lock); 417 418 rtnl_lock(); 419 lock_sock(sk); 420 421 /* remove current filters & unregister */ 422 if (ro->bound) { 423 if (ro->dev) { 424 raw_disable_allfilters(dev_net(ro->dev), ro->dev, sk); 425 netdev_put(ro->dev, &ro->dev_tracker); 426 } else { 427 raw_disable_allfilters(net, NULL, sk); 428 } 429 } 430 431 if (ro->count > 1) 432 kfree(ro->filter); 433 434 ro->ifindex = 0; 435 ro->bound = 0; 436 ro->dev = NULL; 437 ro->count = 0; 438 free_percpu(ro->uniq); 439 440 sock_orphan(sk); 441 sock->sk = NULL; 442 443 release_sock(sk); 444 rtnl_unlock(); 445 446 sock_prot_inuse_add(net, sk->sk_prot, -1); 447 sock_put(sk); 448 449 return 0; 450 } 451 452 static int raw_bind(struct socket *sock, struct sockaddr *uaddr, int len) 453 { 454 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; 455 struct sock *sk = sock->sk; 456 struct raw_sock *ro = raw_sk(sk); 457 struct net_device *dev = NULL; 458 int ifindex; 459 int err = 0; 460 int notify_enetdown = 0; 461 462 if (len < RAW_MIN_NAMELEN) 463 return -EINVAL; 464 if (addr->can_family != AF_CAN) 465 return -EINVAL; 466 467 rtnl_lock(); 468 lock_sock(sk); 469 470 if (ro->bound && addr->can_ifindex == ro->ifindex) 471 goto out; 472 473 if (addr->can_ifindex) { 474 dev = dev_get_by_index(sock_net(sk), addr->can_ifindex); 475 if (!dev) { 476 err = -ENODEV; 477 goto out; 478 } 479 if (dev->type != ARPHRD_CAN) { 480 err = -ENODEV; 481 goto out_put_dev; 482 } 483 484 if (!(dev->flags & IFF_UP)) 485 notify_enetdown = 1; 486 487 ifindex = dev->ifindex; 488 489 /* filters set by default/setsockopt */ 490 err = raw_enable_allfilters(sock_net(sk), dev, sk); 491 if (err) 492 goto out_put_dev; 493 494 } else { 495 ifindex = 0; 496 497 /* filters set by default/setsockopt */ 498 err = raw_enable_allfilters(sock_net(sk), NULL, sk); 499 } 500 501 if (!err) { 502 if (ro->bound) { 503 /* unregister old filters */ 504 if (ro->dev) { 505 raw_disable_allfilters(dev_net(ro->dev), 506 ro->dev, sk); 507 /* drop reference to old ro->dev */ 508 netdev_put(ro->dev, &ro->dev_tracker); 509 } else { 510 raw_disable_allfilters(sock_net(sk), NULL, sk); 511 } 512 } 513 ro->ifindex = ifindex; 514 ro->bound = 1; 515 /* bind() ok -> hold a reference for new ro->dev */ 516 ro->dev = dev; 517 if (ro->dev) 518 netdev_hold(ro->dev, &ro->dev_tracker, GFP_KERNEL); 519 } 520 521 out_put_dev: 522 /* remove potential reference from dev_get_by_index() */ 523 dev_put(dev); 524 out: 525 release_sock(sk); 526 rtnl_unlock(); 527 528 if (notify_enetdown) { 529 sk->sk_err = ENETDOWN; 530 if (!sock_flag(sk, SOCK_DEAD)) 531 sk_error_report(sk); 532 } 533 534 return err; 535 } 536 537 static int raw_getname(struct socket *sock, struct sockaddr *uaddr, 538 int peer) 539 { 540 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; 541 struct sock *sk = sock->sk; 542 struct raw_sock *ro = raw_sk(sk); 543 544 if (peer) 545 return -EOPNOTSUPP; 546 547 memset(addr, 0, RAW_MIN_NAMELEN); 548 addr->can_family = AF_CAN; 549 addr->can_ifindex = ro->ifindex; 550 551 return RAW_MIN_NAMELEN; 552 } 553 554 static int raw_setsockopt(struct socket *sock, int level, int optname, 555 sockptr_t optval, unsigned int optlen) 556 { 557 struct sock *sk = sock->sk; 558 struct raw_sock *ro = raw_sk(sk); 559 struct can_filter *filter = NULL; /* dyn. alloc'ed filters */ 560 struct can_filter sfilter; /* single filter */ 561 struct net_device *dev = NULL; 562 can_err_mask_t err_mask = 0; 563 int fd_frames; 564 int count = 0; 565 int err = 0; 566 567 if (level != SOL_CAN_RAW) 568 return -EINVAL; 569 570 switch (optname) { 571 case CAN_RAW_FILTER: 572 if (optlen % sizeof(struct can_filter) != 0) 573 return -EINVAL; 574 575 if (optlen > CAN_RAW_FILTER_MAX * sizeof(struct can_filter)) 576 return -EINVAL; 577 578 count = optlen / sizeof(struct can_filter); 579 580 if (count > 1) { 581 /* filter does not fit into dfilter => alloc space */ 582 filter = memdup_sockptr(optval, optlen); 583 if (IS_ERR(filter)) 584 return PTR_ERR(filter); 585 } else if (count == 1) { 586 if (copy_from_sockptr(&sfilter, optval, sizeof(sfilter))) 587 return -EFAULT; 588 } 589 590 rtnl_lock(); 591 lock_sock(sk); 592 593 dev = ro->dev; 594 if (ro->bound && dev) { 595 if (dev->reg_state != NETREG_REGISTERED) { 596 if (count > 1) 597 kfree(filter); 598 err = -ENODEV; 599 goto out_fil; 600 } 601 } 602 603 if (ro->bound) { 604 /* (try to) register the new filters */ 605 if (count == 1) 606 err = raw_enable_filters(sock_net(sk), dev, sk, 607 &sfilter, 1); 608 else 609 err = raw_enable_filters(sock_net(sk), dev, sk, 610 filter, count); 611 if (err) { 612 if (count > 1) 613 kfree(filter); 614 goto out_fil; 615 } 616 617 /* remove old filter registrations */ 618 raw_disable_filters(sock_net(sk), dev, sk, ro->filter, 619 ro->count); 620 } 621 622 /* remove old filter space */ 623 if (ro->count > 1) 624 kfree(ro->filter); 625 626 /* link new filters to the socket */ 627 if (count == 1) { 628 /* copy filter data for single filter */ 629 ro->dfilter = sfilter; 630 filter = &ro->dfilter; 631 } 632 ro->filter = filter; 633 ro->count = count; 634 635 out_fil: 636 release_sock(sk); 637 rtnl_unlock(); 638 639 break; 640 641 case CAN_RAW_ERR_FILTER: 642 if (optlen != sizeof(err_mask)) 643 return -EINVAL; 644 645 if (copy_from_sockptr(&err_mask, optval, optlen)) 646 return -EFAULT; 647 648 err_mask &= CAN_ERR_MASK; 649 650 rtnl_lock(); 651 lock_sock(sk); 652 653 dev = ro->dev; 654 if (ro->bound && dev) { 655 if (dev->reg_state != NETREG_REGISTERED) { 656 err = -ENODEV; 657 goto out_err; 658 } 659 } 660 661 /* remove current error mask */ 662 if (ro->bound) { 663 /* (try to) register the new err_mask */ 664 err = raw_enable_errfilter(sock_net(sk), dev, sk, 665 err_mask); 666 667 if (err) 668 goto out_err; 669 670 /* remove old err_mask registration */ 671 raw_disable_errfilter(sock_net(sk), dev, sk, 672 ro->err_mask); 673 } 674 675 /* link new err_mask to the socket */ 676 ro->err_mask = err_mask; 677 678 out_err: 679 release_sock(sk); 680 rtnl_unlock(); 681 682 break; 683 684 case CAN_RAW_LOOPBACK: 685 if (optlen != sizeof(ro->loopback)) 686 return -EINVAL; 687 688 if (copy_from_sockptr(&ro->loopback, optval, optlen)) 689 return -EFAULT; 690 691 break; 692 693 case CAN_RAW_RECV_OWN_MSGS: 694 if (optlen != sizeof(ro->recv_own_msgs)) 695 return -EINVAL; 696 697 if (copy_from_sockptr(&ro->recv_own_msgs, optval, optlen)) 698 return -EFAULT; 699 700 break; 701 702 case CAN_RAW_FD_FRAMES: 703 if (optlen != sizeof(fd_frames)) 704 return -EINVAL; 705 706 if (copy_from_sockptr(&fd_frames, optval, optlen)) 707 return -EFAULT; 708 709 /* Enabling CAN XL includes CAN FD */ 710 if (ro->xl_frames && !fd_frames) 711 return -EINVAL; 712 713 ro->fd_frames = fd_frames; 714 break; 715 716 case CAN_RAW_XL_FRAMES: 717 if (optlen != sizeof(ro->xl_frames)) 718 return -EINVAL; 719 720 if (copy_from_sockptr(&ro->xl_frames, optval, optlen)) 721 return -EFAULT; 722 723 /* Enabling CAN XL includes CAN FD */ 724 if (ro->xl_frames) 725 ro->fd_frames = ro->xl_frames; 726 break; 727 728 case CAN_RAW_XL_VCID_OPTS: 729 if (optlen != sizeof(ro->raw_vcid_opts)) 730 return -EINVAL; 731 732 if (copy_from_sockptr(&ro->raw_vcid_opts, optval, optlen)) 733 return -EFAULT; 734 735 /* prepare 32 bit values for handling in hot path */ 736 ro->tx_vcid_shifted = ro->raw_vcid_opts.tx_vcid << CANXL_VCID_OFFSET; 737 ro->rx_vcid_shifted = ro->raw_vcid_opts.rx_vcid << CANXL_VCID_OFFSET; 738 ro->rx_vcid_mask_shifted = ro->raw_vcid_opts.rx_vcid_mask << CANXL_VCID_OFFSET; 739 break; 740 741 case CAN_RAW_JOIN_FILTERS: 742 if (optlen != sizeof(ro->join_filters)) 743 return -EINVAL; 744 745 if (copy_from_sockptr(&ro->join_filters, optval, optlen)) 746 return -EFAULT; 747 748 break; 749 750 default: 751 return -ENOPROTOOPT; 752 } 753 return err; 754 } 755 756 static int raw_getsockopt(struct socket *sock, int level, int optname, 757 char __user *optval, int __user *optlen) 758 { 759 struct sock *sk = sock->sk; 760 struct raw_sock *ro = raw_sk(sk); 761 int len; 762 void *val; 763 764 if (level != SOL_CAN_RAW) 765 return -EINVAL; 766 if (get_user(len, optlen)) 767 return -EFAULT; 768 if (len < 0) 769 return -EINVAL; 770 771 switch (optname) { 772 case CAN_RAW_FILTER: { 773 int err = 0; 774 775 lock_sock(sk); 776 if (ro->count > 0) { 777 int fsize = ro->count * sizeof(struct can_filter); 778 779 /* user space buffer to small for filter list? */ 780 if (len < fsize) { 781 /* return -ERANGE and needed space in optlen */ 782 err = -ERANGE; 783 if (put_user(fsize, optlen)) 784 err = -EFAULT; 785 } else { 786 if (len > fsize) 787 len = fsize; 788 if (copy_to_user(optval, ro->filter, len)) 789 err = -EFAULT; 790 } 791 } else { 792 len = 0; 793 } 794 release_sock(sk); 795 796 if (!err) 797 err = put_user(len, optlen); 798 return err; 799 } 800 case CAN_RAW_ERR_FILTER: 801 if (len > sizeof(can_err_mask_t)) 802 len = sizeof(can_err_mask_t); 803 val = &ro->err_mask; 804 break; 805 806 case CAN_RAW_LOOPBACK: 807 if (len > sizeof(int)) 808 len = sizeof(int); 809 val = &ro->loopback; 810 break; 811 812 case CAN_RAW_RECV_OWN_MSGS: 813 if (len > sizeof(int)) 814 len = sizeof(int); 815 val = &ro->recv_own_msgs; 816 break; 817 818 case CAN_RAW_FD_FRAMES: 819 if (len > sizeof(int)) 820 len = sizeof(int); 821 val = &ro->fd_frames; 822 break; 823 824 case CAN_RAW_XL_FRAMES: 825 if (len > sizeof(int)) 826 len = sizeof(int); 827 val = &ro->xl_frames; 828 break; 829 830 case CAN_RAW_XL_VCID_OPTS: { 831 int err = 0; 832 833 /* user space buffer to small for VCID opts? */ 834 if (len < sizeof(ro->raw_vcid_opts)) { 835 /* return -ERANGE and needed space in optlen */ 836 err = -ERANGE; 837 if (put_user(sizeof(ro->raw_vcid_opts), optlen)) 838 err = -EFAULT; 839 } else { 840 if (len > sizeof(ro->raw_vcid_opts)) 841 len = sizeof(ro->raw_vcid_opts); 842 if (copy_to_user(optval, &ro->raw_vcid_opts, len)) 843 err = -EFAULT; 844 } 845 if (!err) 846 err = put_user(len, optlen); 847 return err; 848 } 849 case CAN_RAW_JOIN_FILTERS: 850 if (len > sizeof(int)) 851 len = sizeof(int); 852 val = &ro->join_filters; 853 break; 854 855 default: 856 return -ENOPROTOOPT; 857 } 858 859 if (put_user(len, optlen)) 860 return -EFAULT; 861 if (copy_to_user(optval, val, len)) 862 return -EFAULT; 863 return 0; 864 } 865 866 static void raw_put_canxl_vcid(struct raw_sock *ro, struct sk_buff *skb) 867 { 868 struct canxl_frame *cxl = (struct canxl_frame *)skb->data; 869 870 /* sanitize non CAN XL bits */ 871 cxl->prio &= (CANXL_PRIO_MASK | CANXL_VCID_MASK); 872 873 /* clear VCID in CAN XL frame if pass through is disabled */ 874 if (!(ro->raw_vcid_opts.flags & CAN_RAW_XL_VCID_TX_PASS)) 875 cxl->prio &= CANXL_PRIO_MASK; 876 877 /* set VCID in CAN XL frame if enabled */ 878 if (ro->raw_vcid_opts.flags & CAN_RAW_XL_VCID_TX_SET) { 879 cxl->prio &= CANXL_PRIO_MASK; 880 cxl->prio |= ro->tx_vcid_shifted; 881 } 882 } 883 884 static unsigned int raw_check_txframe(struct raw_sock *ro, struct sk_buff *skb, int mtu) 885 { 886 /* Classical CAN -> no checks for flags and device capabilities */ 887 if (can_is_can_skb(skb)) 888 return CAN_MTU; 889 890 /* CAN FD -> needs to be enabled and a CAN FD or CAN XL device */ 891 if (ro->fd_frames && can_is_canfd_skb(skb) && 892 (mtu == CANFD_MTU || can_is_canxl_dev_mtu(mtu))) 893 return CANFD_MTU; 894 895 /* CAN XL -> needs to be enabled and a CAN XL device */ 896 if (ro->xl_frames && can_is_canxl_skb(skb) && 897 can_is_canxl_dev_mtu(mtu)) 898 return CANXL_MTU; 899 900 return 0; 901 } 902 903 static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) 904 { 905 struct sock *sk = sock->sk; 906 struct raw_sock *ro = raw_sk(sk); 907 struct sockcm_cookie sockc; 908 struct sk_buff *skb; 909 struct net_device *dev; 910 unsigned int txmtu; 911 int ifindex; 912 int err = -EINVAL; 913 914 /* check for valid CAN frame sizes */ 915 if (size < CANXL_HDR_SIZE + CANXL_MIN_DLEN || size > CANXL_MTU) 916 return -EINVAL; 917 918 if (msg->msg_name) { 919 DECLARE_SOCKADDR(struct sockaddr_can *, addr, msg->msg_name); 920 921 if (msg->msg_namelen < RAW_MIN_NAMELEN) 922 return -EINVAL; 923 924 if (addr->can_family != AF_CAN) 925 return -EINVAL; 926 927 ifindex = addr->can_ifindex; 928 } else { 929 ifindex = ro->ifindex; 930 } 931 932 dev = dev_get_by_index(sock_net(sk), ifindex); 933 if (!dev) 934 return -ENXIO; 935 936 skb = sock_alloc_send_skb(sk, size + sizeof(struct can_skb_priv), 937 msg->msg_flags & MSG_DONTWAIT, &err); 938 if (!skb) 939 goto put_dev; 940 941 can_skb_reserve(skb); 942 can_skb_prv(skb)->ifindex = dev->ifindex; 943 can_skb_prv(skb)->skbcnt = 0; 944 945 /* fill the skb before testing for valid CAN frames */ 946 err = memcpy_from_msg(skb_put(skb, size), msg, size); 947 if (err < 0) 948 goto free_skb; 949 950 err = -EINVAL; 951 952 /* check for valid CAN (CC/FD/XL) frame content */ 953 txmtu = raw_check_txframe(ro, skb, dev->mtu); 954 if (!txmtu) 955 goto free_skb; 956 957 /* only CANXL: clear/forward/set VCID value */ 958 if (txmtu == CANXL_MTU) 959 raw_put_canxl_vcid(ro, skb); 960 961 sockcm_init(&sockc, sk); 962 if (msg->msg_controllen) { 963 err = sock_cmsg_send(sk, msg, &sockc); 964 if (unlikely(err)) 965 goto free_skb; 966 } 967 968 skb->dev = dev; 969 skb->priority = sockc.priority; 970 skb->mark = sockc.mark; 971 skb->tstamp = sockc.transmit_time; 972 973 skb_setup_tx_timestamp(skb, &sockc); 974 975 err = can_send(skb, ro->loopback); 976 977 dev_put(dev); 978 979 if (err) 980 goto send_failed; 981 982 return size; 983 984 free_skb: 985 kfree_skb(skb); 986 put_dev: 987 dev_put(dev); 988 send_failed: 989 return err; 990 } 991 992 static int raw_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 993 int flags) 994 { 995 struct sock *sk = sock->sk; 996 struct sk_buff *skb; 997 int err = 0; 998 999 if (flags & MSG_ERRQUEUE) 1000 return sock_recv_errqueue(sk, msg, size, 1001 SOL_CAN_RAW, SCM_CAN_RAW_ERRQUEUE); 1002 1003 skb = skb_recv_datagram(sk, flags, &err); 1004 if (!skb) 1005 return err; 1006 1007 if (size < skb->len) 1008 msg->msg_flags |= MSG_TRUNC; 1009 else 1010 size = skb->len; 1011 1012 err = memcpy_to_msg(msg, skb->data, size); 1013 if (err < 0) { 1014 skb_free_datagram(sk, skb); 1015 return err; 1016 } 1017 1018 sock_recv_cmsgs(msg, sk, skb); 1019 1020 if (msg->msg_name) { 1021 __sockaddr_check_size(RAW_MIN_NAMELEN); 1022 msg->msg_namelen = RAW_MIN_NAMELEN; 1023 memcpy(msg->msg_name, skb->cb, msg->msg_namelen); 1024 } 1025 1026 /* assign the flags that have been recorded in raw_rcv() */ 1027 msg->msg_flags |= *(raw_flags(skb)); 1028 1029 skb_free_datagram(sk, skb); 1030 1031 return size; 1032 } 1033 1034 static int raw_sock_no_ioctlcmd(struct socket *sock, unsigned int cmd, 1035 unsigned long arg) 1036 { 1037 /* no ioctls for socket layer -> hand it down to NIC layer */ 1038 return -ENOIOCTLCMD; 1039 } 1040 1041 static const struct proto_ops raw_ops = { 1042 .family = PF_CAN, 1043 .release = raw_release, 1044 .bind = raw_bind, 1045 .connect = sock_no_connect, 1046 .socketpair = sock_no_socketpair, 1047 .accept = sock_no_accept, 1048 .getname = raw_getname, 1049 .poll = datagram_poll, 1050 .ioctl = raw_sock_no_ioctlcmd, 1051 .gettstamp = sock_gettstamp, 1052 .listen = sock_no_listen, 1053 .shutdown = sock_no_shutdown, 1054 .setsockopt = raw_setsockopt, 1055 .getsockopt = raw_getsockopt, 1056 .sendmsg = raw_sendmsg, 1057 .recvmsg = raw_recvmsg, 1058 .mmap = sock_no_mmap, 1059 }; 1060 1061 static struct proto raw_proto __read_mostly = { 1062 .name = "CAN_RAW", 1063 .owner = THIS_MODULE, 1064 .obj_size = sizeof(struct raw_sock), 1065 .init = raw_init, 1066 }; 1067 1068 static const struct can_proto raw_can_proto = { 1069 .type = SOCK_RAW, 1070 .protocol = CAN_RAW, 1071 .ops = &raw_ops, 1072 .prot = &raw_proto, 1073 }; 1074 1075 static struct notifier_block canraw_notifier = { 1076 .notifier_call = raw_notifier 1077 }; 1078 1079 static __init int raw_module_init(void) 1080 { 1081 int err; 1082 1083 pr_info("can: raw protocol\n"); 1084 1085 err = register_netdevice_notifier(&canraw_notifier); 1086 if (err) 1087 return err; 1088 1089 err = can_proto_register(&raw_can_proto); 1090 if (err < 0) { 1091 pr_err("can: registration of raw protocol failed\n"); 1092 goto register_proto_failed; 1093 } 1094 1095 return 0; 1096 1097 register_proto_failed: 1098 unregister_netdevice_notifier(&canraw_notifier); 1099 return err; 1100 } 1101 1102 static __exit void raw_module_exit(void) 1103 { 1104 can_proto_unregister(&raw_can_proto); 1105 unregister_netdevice_notifier(&canraw_notifier); 1106 } 1107 1108 module_init(raw_module_init); 1109 module_exit(raw_module_exit); 1110