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