net/can/j1939/socket.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 // Copyright (c) 2010-2011 EIA Electronics,
   3 //                         Pieter Beyens <pieter.beyens@eia.be>
   4 // Copyright (c) 2010-2011 EIA Electronics,
   5 //                         Kurt Van Dijck <kurt.van.dijck@eia.be>
   6 // Copyright (c) 2018 Protonic,
   7 //                         Robin van der Gracht <robin@protonic.nl>
   8 // Copyright (c) 2017-2019 Pengutronix,
   9 //                         Marc Kleine-Budde <kernel@pengutronix.de>
  10 // Copyright (c) 2017-2019 Pengutronix,
  11 //                         Oleksij Rempel <kernel@pengutronix.de>
  12
  13 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  14
  15 #include <linux/can/core.h>
  16 #include <linux/can/skb.h>
  17 #include <linux/errqueue.h>
  18 #include <linux/if_arp.h>
  19
  20 #include "j1939-priv.h"
  21
  22 #define J1939_MIN_NAMELEN CAN_REQUIRED_SIZE(struct sockaddr_can, can_addr.j1939)
  23
  24 /* conversion function between struct sock::sk_priority from linux and
  25  * j1939 priority field
  26  */
  27 static inline priority_t j1939_prio(u32 sk_priority)
  28 {
  29         sk_priority = min(sk_priority, 7U);
  30
  31         return 7 - sk_priority;
  32 }
  33
  34 static inline u32 j1939_to_sk_priority(priority_t prio)
  35 {
  36         return 7 - prio;
  37 }
  38
  39 /* function to see if pgn is to be evaluated */
  40 static inline bool j1939_pgn_is_valid(pgn_t pgn)
  41 {
  42         return pgn <= J1939_PGN_MAX;
  43 }
  44
  45 /* test function to avoid non-zero DA placeholder for pdu1 pgn's */
  46 static inline bool j1939_pgn_is_clean_pdu(pgn_t pgn)
  47 {
  48         if (j1939_pgn_is_pdu1(pgn))
  49                 return !(pgn & 0xff);
  50         else
  51                 return true;
  52 }
  53
  54 static inline void j1939_sock_pending_add(struct sock *sk)
  55 {
  56         struct j1939_sock *jsk = j1939_sk(sk);
  57
  58         atomic_inc(&jsk->skb_pending);
  59 }
  60
  61 static int j1939_sock_pending_get(struct sock *sk)
  62 {
  63         struct j1939_sock *jsk = j1939_sk(sk);
  64
  65         return atomic_read(&jsk->skb_pending);
  66 }
  67
  68 void j1939_sock_pending_del(struct sock *sk)
  69 {
  70         struct j1939_sock *jsk = j1939_sk(sk);
  71
  72         /* atomic_dec_return returns the new value */
  73         if (!atomic_dec_return(&jsk->skb_pending))
  74                 wake_up(&jsk->waitq);   /* no pending SKB's */
  75 }
  76
  77 static void j1939_jsk_add(struct j1939_priv *priv, struct j1939_sock *jsk)
  78 {
  79         jsk->state |= J1939_SOCK_BOUND;
  80         j1939_priv_get(priv);
  81
  82         spin_lock_bh(&priv->j1939_socks_lock);
  83         list_add_tail(&jsk->list, &priv->j1939_socks);
  84         spin_unlock_bh(&priv->j1939_socks_lock);
  85 }
  86
  87 static void j1939_jsk_del(struct j1939_priv *priv, struct j1939_sock *jsk)
  88 {
  89         spin_lock_bh(&priv->j1939_socks_lock);
  90         list_del_init(&jsk->list);
  91         spin_unlock_bh(&priv->j1939_socks_lock);
  92
  93         j1939_priv_put(priv);
  94         jsk->state &= ~J1939_SOCK_BOUND;
  95 }
  96
  97 static bool j1939_sk_queue_session(struct j1939_session *session)
  98 {
  99         struct j1939_sock *jsk = j1939_sk(session->sk);
 100         bool empty;
 101
 102         spin_lock_bh(&jsk->sk_session_queue_lock);
 103         empty = list_empty(&jsk->sk_session_queue);
 104         j1939_session_get(session);
 105         list_add_tail(&session->sk_session_queue_entry, &jsk->sk_session_queue);
 106         spin_unlock_bh(&jsk->sk_session_queue_lock);
 107         j1939_sock_pending_add(&jsk->sk);
 108
 109         return empty;
 110 }
 111
 112 static struct
 113 j1939_session *j1939_sk_get_incomplete_session(struct j1939_sock *jsk)
 114 {
 115         struct j1939_session *session = NULL;
 116
 117         spin_lock_bh(&jsk->sk_session_queue_lock);
 118         if (!list_empty(&jsk->sk_session_queue)) {
 119                 session = list_last_entry(&jsk->sk_session_queue,
 120                                           struct j1939_session,
 121                                           sk_session_queue_entry);
 122                 if (session->total_queued_size == session->total_message_size)
 123                         session = NULL;
 124                 else
 125                         j1939_session_get(session);
 126         }
 127         spin_unlock_bh(&jsk->sk_session_queue_lock);
 128
 129         return session;
 130 }
 131
 132 static void j1939_sk_queue_drop_all(struct j1939_priv *priv,
 133                                     struct j1939_sock *jsk, int err)
 134 {
 135         struct j1939_session *session, *tmp;
 136
 137         netdev_dbg(priv->ndev, "%s: err: %i\n", __func__, err);
 138         spin_lock_bh(&jsk->sk_session_queue_lock);
 139         list_for_each_entry_safe(session, tmp, &jsk->sk_session_queue,
 140                                  sk_session_queue_entry) {
 141                 list_del_init(&session->sk_session_queue_entry);
 142                 session->err = err;
 143                 j1939_session_put(session);
 144         }
 145         spin_unlock_bh(&jsk->sk_session_queue_lock);
 146 }
 147
 148 static void j1939_sk_queue_activate_next_locked(struct j1939_session *session)
 149 {
 150         struct j1939_sock *jsk;
 151         struct j1939_session *first;
 152         int err;
 153
 154         /* RX-Session don't have a socket (yet) */
 155         if (!session->sk)
 156                 return;
 157
 158         jsk = j1939_sk(session->sk);
 159         lockdep_assert_held(&jsk->sk_session_queue_lock);
 160
 161         err = session->err;
 162
 163         first = list_first_entry_or_null(&jsk->sk_session_queue,
 164                                          struct j1939_session,
 165                                          sk_session_queue_entry);
 166
 167         /* Some else has already activated the next session */
 168         if (first != session)
 169                 return;
 170
 171 activate_next:
 172         list_del_init(&first->sk_session_queue_entry);
 173         j1939_session_put(first);
 174         first = list_first_entry_or_null(&jsk->sk_session_queue,
 175                                          struct j1939_session,
 176                                          sk_session_queue_entry);
 177         if (!first)
 178                 return;
 179
 180         if (WARN_ON_ONCE(j1939_session_activate(first))) {
 181                 first->err = -EBUSY;
 182                 goto activate_next;
 183         } else {
 184                 /* Give receiver some time (arbitrary chosen) to recover */
 185                 int time_ms = 0;
 186
 187                 if (err)
 188                         time_ms = 10 + prandom_u32_max(16);
 189
 190                 j1939_tp_schedule_txtimer(first, time_ms);
 191         }
 192 }
 193
 194 void j1939_sk_queue_activate_next(struct j1939_session *session)
 195 {
 196         struct j1939_sock *jsk;
 197
 198         if (!session->sk)
 199                 return;
 200
 201         jsk = j1939_sk(session->sk);
 202
 203         spin_lock_bh(&jsk->sk_session_queue_lock);
 204         j1939_sk_queue_activate_next_locked(session);
 205         spin_unlock_bh(&jsk->sk_session_queue_lock);
 206 }
 207
 208 static bool j1939_sk_match_dst(struct j1939_sock *jsk,
 209                                const struct j1939_sk_buff_cb *skcb)
 210 {
 211         if ((jsk->state & J1939_SOCK_PROMISC))
 212                 return true;
 213
 214         /* Destination address filter */
 215         if (jsk->addr.src_name && skcb->addr.dst_name) {
 216                 if (jsk->addr.src_name != skcb->addr.dst_name)
 217                         return false;
 218         } else {
 219                 /* receive (all sockets) if
 220                  * - all packages that match our bind() address
 221                  * - all broadcast on a socket if SO_BROADCAST
 222                  *   is set
 223                  */
 224                 if (j1939_address_is_unicast(skcb->addr.da)) {
 225                         if (jsk->addr.sa != skcb->addr.da)
 226                                 return false;
 227                 } else if (!sock_flag(&jsk->sk, SOCK_BROADCAST)) {
 228                         /* receiving broadcast without SO_BROADCAST
 229                          * flag is not allowed
 230                          */
 231                         return false;
 232                 }
 233         }
 234
 235         /* Source address filter */
 236         if (jsk->state & J1939_SOCK_CONNECTED) {
 237                 /* receive (all sockets) if
 238                  * - all packages that match our connect() name or address
 239                  */
 240                 if (jsk->addr.dst_name && skcb->addr.src_name) {
 241                         if (jsk->addr.dst_name != skcb->addr.src_name)
 242                                 return false;
 243                 } else {
 244                         if (jsk->addr.da != skcb->addr.sa)
 245                                 return false;
 246                 }
 247         }
 248
 249         /* PGN filter */
 250         if (j1939_pgn_is_valid(jsk->pgn_rx_filter) &&
 251             jsk->pgn_rx_filter != skcb->addr.pgn)
 252                 return false;
 253
 254         return true;
 255 }
 256
 257 /* matches skb control buffer (addr) with a j1939 filter */
 258 static bool j1939_sk_match_filter(struct j1939_sock *jsk,
 259                                   const struct j1939_sk_buff_cb *skcb)
 260 {
 261         const struct j1939_filter *f = jsk->filters;
 262         int nfilter = jsk->nfilters;
 263
 264         if (!nfilter)
 265                 /* receive all when no filters are assigned */
 266                 return true;
 267
 268         for (; nfilter; ++f, --nfilter) {
 269                 if ((skcb->addr.pgn & f->pgn_mask) != f->pgn)
 270                         continue;
 271                 if ((skcb->addr.sa & f->addr_mask) != f->addr)
 272                         continue;
 273                 if ((skcb->addr.src_name & f->name_mask) != f->name)
 274                         continue;
 275                 return true;
 276         }
 277         return false;
 278 }
 279
 280 static bool j1939_sk_recv_match_one(struct j1939_sock *jsk,
 281                                     const struct j1939_sk_buff_cb *skcb)
 282 {
 283         if (!(jsk->state & J1939_SOCK_BOUND))
 284                 return false;
 285
 286         if (!j1939_sk_match_dst(jsk, skcb))
 287                 return false;
 288
 289         if (!j1939_sk_match_filter(jsk, skcb))
 290                 return false;
 291
 292         return true;
 293 }
 294
 295 static void j1939_sk_recv_one(struct j1939_sock *jsk, struct sk_buff *oskb)
 296 {
 297         const struct j1939_sk_buff_cb *oskcb = j1939_skb_to_cb(oskb);
 298         struct j1939_sk_buff_cb *skcb;
 299         struct sk_buff *skb;
 300
 301         if (oskb->sk == &jsk->sk)
 302                 return;
 303
 304         if (!j1939_sk_recv_match_one(jsk, oskcb))
 305                 return;
 306
 307         skb = skb_clone(oskb, GFP_ATOMIC);
 308         if (!skb) {
 309                 pr_warn("skb clone failed\n");
 310                 return;
 311         }
 312         can_skb_set_owner(skb, oskb->sk);
 313
 314         skcb = j1939_skb_to_cb(skb);
 315         skcb->msg_flags &= ~(MSG_DONTROUTE);
 316         if (skb->sk)
 317                 skcb->msg_flags |= MSG_DONTROUTE;
 318
 319         if (sock_queue_rcv_skb(&jsk->sk, skb) < 0)
 320                 kfree_skb(skb);
 321 }
 322
 323 bool j1939_sk_recv_match(struct j1939_priv *priv, struct j1939_sk_buff_cb *skcb)
 324 {
 325         struct j1939_sock *jsk;
 326         bool match = false;
 327
 328         spin_lock_bh(&priv->j1939_socks_lock);
 329         list_for_each_entry(jsk, &priv->j1939_socks, list) {
 330                 match = j1939_sk_recv_match_one(jsk, skcb);
 331                 if (match)
 332                         break;
 333         }
 334         spin_unlock_bh(&priv->j1939_socks_lock);
 335
 336         return match;
 337 }
 338
 339 void j1939_sk_recv(struct j1939_priv *priv, struct sk_buff *skb)
 340 {
 341         struct j1939_sock *jsk;
 342
 343         spin_lock_bh(&priv->j1939_socks_lock);
 344         list_for_each_entry(jsk, &priv->j1939_socks, list) {
 345                 j1939_sk_recv_one(jsk, skb);
 346         }
 347         spin_unlock_bh(&priv->j1939_socks_lock);
 348 }
 349
 350 static void j1939_sk_sock_destruct(struct sock *sk)
 351 {
 352         struct j1939_sock *jsk = j1939_sk(sk);
 353
 354         /* This function will be call by the generic networking code, when then
 355          * the socket is ultimately closed (sk->sk_destruct).
 356          *
 357          * The race between
 358          * - processing a received CAN frame
 359          *   (can_receive -> j1939_can_recv)
 360          *   and accessing j1939_priv
 361          * ... and ...
 362          * - closing a socket
 363          *   (j1939_can_rx_unregister -> can_rx_unregister)
 364          *   and calling the final j1939_priv_put()
 365          *
 366          * is avoided by calling the final j1939_priv_put() from this
 367          * RCU deferred cleanup call.
 368          */
 369         if (jsk->priv) {
 370                 j1939_priv_put(jsk->priv);
 371                 jsk->priv = NULL;
 372         }
 373
 374         /* call generic CAN sock destruct */
 375         can_sock_destruct(sk);
 376 }
 377
 378 static int j1939_sk_init(struct sock *sk)
 379 {
 380         struct j1939_sock *jsk = j1939_sk(sk);
 381
 382         /* Ensure that "sk" is first member in "struct j1939_sock", so that we
 383          * can skip it during memset().
 384          */
 385         BUILD_BUG_ON(offsetof(struct j1939_sock, sk) != 0);
 386         memset((void *)jsk + sizeof(jsk->sk), 0x0,
 387                sizeof(*jsk) - sizeof(jsk->sk));
 388
 389         INIT_LIST_HEAD(&jsk->list);
 390         init_waitqueue_head(&jsk->waitq);
 391         jsk->sk.sk_priority = j1939_to_sk_priority(6);
 392         jsk->sk.sk_reuse = 1; /* per default */
 393         jsk->addr.sa = J1939_NO_ADDR;
 394         jsk->addr.da = J1939_NO_ADDR;
 395         jsk->addr.pgn = J1939_NO_PGN;
 396         jsk->pgn_rx_filter = J1939_NO_PGN;
 397         atomic_set(&jsk->skb_pending, 0);
 398         spin_lock_init(&jsk->sk_session_queue_lock);
 399         INIT_LIST_HEAD(&jsk->sk_session_queue);
 400         sk->sk_destruct = j1939_sk_sock_destruct;
 401         sk->sk_protocol = CAN_J1939;
 402
 403         return 0;
 404 }
 405
 406 static int j1939_sk_sanity_check(struct sockaddr_can *addr, int len)
 407 {
 408         if (!addr)
 409                 return -EDESTADDRREQ;
 410         if (len < J1939_MIN_NAMELEN)
 411                 return -EINVAL;
 412         if (addr->can_family != AF_CAN)
 413                 return -EINVAL;
 414         if (!addr->can_ifindex)
 415                 return -ENODEV;
 416         if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn) &&
 417             !j1939_pgn_is_clean_pdu(addr->can_addr.j1939.pgn))
 418                 return -EINVAL;
 419
 420         return 0;
 421 }
 422
 423 static int j1939_sk_bind(struct socket *sock, struct sockaddr *uaddr, int len)
 424 {
 425         struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
 426         struct j1939_sock *jsk = j1939_sk(sock->sk);
 427         struct j1939_priv *priv;
 428         struct sock *sk;
 429         struct net *net;
 430         int ret = 0;
 431
 432         ret = j1939_sk_sanity_check(addr, len);
 433         if (ret)
 434                 return ret;
 435
 436         lock_sock(sock->sk);
 437
 438         priv = jsk->priv;
 439         sk = sock->sk;
 440         net = sock_net(sk);
 441
 442         /* Already bound to an interface? */
 443         if (jsk->state & J1939_SOCK_BOUND) {
 444                 /* A re-bind() to a different interface is not
 445                  * supported.
 446                  */
 447                 if (jsk->ifindex != addr->can_ifindex) {
 448                         ret = -EINVAL;
 449                         goto out_release_sock;
 450                 }
 451
 452                 /* drop old references */
 453                 j1939_jsk_del(priv, jsk);
 454                 j1939_local_ecu_put(priv, jsk->addr.src_name, jsk->addr.sa);
 455         } else {
 456                 struct net_device *ndev;
 457
 458                 ndev = dev_get_by_index(net, addr->can_ifindex);
 459                 if (!ndev) {
 460                         ret = -ENODEV;
 461                         goto out_release_sock;
 462                 }
 463
 464                 if (ndev->type != ARPHRD_CAN) {
 465                         dev_put(ndev);
 466                         ret = -ENODEV;
 467                         goto out_release_sock;
 468                 }
 469
 470                 if (!ndev->ml_priv) {
 471                         netdev_warn_once(ndev,
 472                                          "No CAN mid layer private allocated, please fix your driver and use alloc_candev()!\n");
 473                         dev_put(ndev);
 474                         ret = -ENODEV;
 475                         goto out_release_sock;
 476                 }
 477
 478                 priv = j1939_netdev_start(ndev);
 479                 dev_put(ndev);
 480                 if (IS_ERR(priv)) {
 481                         ret = PTR_ERR(priv);
 482                         goto out_release_sock;
 483                 }
 484
 485                 jsk->ifindex = addr->can_ifindex;
 486
 487                 /* the corresponding j1939_priv_put() is called via
 488                  * sk->sk_destruct, which points to j1939_sk_sock_destruct()
 489                  */
 490                 j1939_priv_get(priv);
 491                 jsk->priv = priv;
 492         }
 493
 494         /* set default transmit pgn */
 495         if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn))
 496                 jsk->pgn_rx_filter = addr->can_addr.j1939.pgn;
 497         jsk->addr.src_name = addr->can_addr.j1939.name;
 498         jsk->addr.sa = addr->can_addr.j1939.addr;
 499
 500         /* get new references */
 501         ret = j1939_local_ecu_get(priv, jsk->addr.src_name, jsk->addr.sa);
 502         if (ret) {
 503                 j1939_netdev_stop(priv);
 504                 goto out_release_sock;
 505         }
 506
 507         j1939_jsk_add(priv, jsk);
 508
 509  out_release_sock: /* fall through */
 510         release_sock(sock->sk);
 511
 512         return ret;
 513 }
 514
 515 static int j1939_sk_connect(struct socket *sock, struct sockaddr *uaddr,
 516                             int len, int flags)
 517 {
 518         struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
 519         struct j1939_sock *jsk = j1939_sk(sock->sk);
 520         int ret = 0;
 521
 522         ret = j1939_sk_sanity_check(addr, len);
 523         if (ret)
 524                 return ret;
 525
 526         lock_sock(sock->sk);
 527
 528         /* bind() before connect() is mandatory */
 529         if (!(jsk->state & J1939_SOCK_BOUND)) {
 530                 ret = -EINVAL;
 531                 goto out_release_sock;
 532         }
 533
 534         /* A connect() to a different interface is not supported. */
 535         if (jsk->ifindex != addr->can_ifindex) {
 536                 ret = -EINVAL;
 537                 goto out_release_sock;
 538         }
 539
 540         if (!addr->can_addr.j1939.name &&
 541             addr->can_addr.j1939.addr == J1939_NO_ADDR &&
 542             !sock_flag(&jsk->sk, SOCK_BROADCAST)) {
 543                 /* broadcast, but SO_BROADCAST not set */
 544                 ret = -EACCES;
 545                 goto out_release_sock;
 546         }
 547
 548         jsk->addr.dst_name = addr->can_addr.j1939.name;
 549         jsk->addr.da = addr->can_addr.j1939.addr;
 550
 551         if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn))
 552                 jsk->addr.pgn = addr->can_addr.j1939.pgn;
 553
 554         jsk->state |= J1939_SOCK_CONNECTED;
 555
 556  out_release_sock: /* fall through */
 557         release_sock(sock->sk);
 558
 559         return ret;
 560 }
 561
 562 static void j1939_sk_sock2sockaddr_can(struct sockaddr_can *addr,
 563                                        const struct j1939_sock *jsk, int peer)
 564 {
 565         /* There are two holes (2 bytes and 3 bytes) to clear to avoid
 566          * leaking kernel information to user space.
 567          */
 568         memset(addr, 0, J1939_MIN_NAMELEN);
 569
 570         addr->can_family = AF_CAN;
 571         addr->can_ifindex = jsk->ifindex;
 572         addr->can_addr.j1939.pgn = jsk->addr.pgn;
 573         if (peer) {
 574                 addr->can_addr.j1939.name = jsk->addr.dst_name;
 575                 addr->can_addr.j1939.addr = jsk->addr.da;
 576         } else {
 577                 addr->can_addr.j1939.name = jsk->addr.src_name;
 578                 addr->can_addr.j1939.addr = jsk->addr.sa;
 579         }
 580 }
 581
 582 static int j1939_sk_getname(struct socket *sock, struct sockaddr *uaddr,
 583                             int peer)
 584 {
 585         struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
 586         struct sock *sk = sock->sk;
 587         struct j1939_sock *jsk = j1939_sk(sk);
 588         int ret = 0;
 589
 590         lock_sock(sk);
 591
 592         if (peer && !(jsk->state & J1939_SOCK_CONNECTED)) {
 593                 ret = -EADDRNOTAVAIL;
 594                 goto failure;
 595         }
 596
 597         j1939_sk_sock2sockaddr_can(addr, jsk, peer);
 598         ret = J1939_MIN_NAMELEN;
 599
 600  failure:
 601         release_sock(sk);
 602
 603         return ret;
 604 }
 605
 606 static int j1939_sk_release(struct socket *sock)
 607 {
 608         struct sock *sk = sock->sk;
 609         struct j1939_sock *jsk;
 610
 611         if (!sk)
 612                 return 0;
 613
 614         lock_sock(sk);
 615         jsk = j1939_sk(sk);
 616
 617         if (jsk->state & J1939_SOCK_BOUND) {
 618                 struct j1939_priv *priv = jsk->priv;
 619
 620                 if (wait_event_interruptible(jsk->waitq,
 621                                              !j1939_sock_pending_get(&jsk->sk))) {
 622                         j1939_cancel_active_session(priv, sk);
 623                         j1939_sk_queue_drop_all(priv, jsk, ESHUTDOWN);
 624                 }
 625
 626                 j1939_jsk_del(priv, jsk);
 627
 628                 j1939_local_ecu_put(priv, jsk->addr.src_name,
 629                                     jsk->addr.sa);
 630
 631                 j1939_netdev_stop(priv);
 632         }
 633
 634         kfree(jsk->filters);
 635         sock_orphan(sk);
 636         sock->sk = NULL;
 637
 638         release_sock(sk);
 639         sock_put(sk);
 640
 641         return 0;
 642 }
 643
 644 static int j1939_sk_setsockopt_flag(struct j1939_sock *jsk, sockptr_t optval,
 645                                     unsigned int optlen, int flag)
 646 {
 647         int tmp;
 648
 649         if (optlen != sizeof(tmp))
 650                 return -EINVAL;
 651         if (copy_from_sockptr(&tmp, optval, optlen))
 652                 return -EFAULT;
 653         lock_sock(&jsk->sk);
 654         if (tmp)
 655                 jsk->state |= flag;
 656         else
 657                 jsk->state &= ~flag;
 658         release_sock(&jsk->sk);
 659         return tmp;
 660 }
 661
 662 static int j1939_sk_setsockopt(struct socket *sock, int level, int optname,
 663                                sockptr_t optval, unsigned int optlen)
 664 {
 665         struct sock *sk = sock->sk;
 666         struct j1939_sock *jsk = j1939_sk(sk);
 667         int tmp, count = 0, ret = 0;
 668         struct j1939_filter *filters = NULL, *ofilters;
 669
 670         if (level != SOL_CAN_J1939)
 671                 return -EINVAL;
 672
 673         switch (optname) {
 674         case SO_J1939_FILTER:
 675                 if (!sockptr_is_null(optval)) {
 676                         struct j1939_filter *f;
 677                         int c;
 678
 679                         if (optlen % sizeof(*filters) != 0)
 680                                 return -EINVAL;
 681
 682                         if (optlen > J1939_FILTER_MAX *
 683                             sizeof(struct j1939_filter))
 684                                 return -EINVAL;
 685
 686                         count = optlen / sizeof(*filters);
 687                         filters = memdup_sockptr(optval, optlen);
 688                         if (IS_ERR(filters))
 689                                 return PTR_ERR(filters);
 690
 691                         for (f = filters, c = count; c; f++, c--) {
 692                                 f->name &= f->name_mask;
 693                                 f->pgn &= f->pgn_mask;
 694                                 f->addr &= f->addr_mask;
 695                         }
 696                 }
 697
 698                 lock_sock(&jsk->sk);
 699                 ofilters = jsk->filters;
 700                 jsk->filters = filters;
 701                 jsk->nfilters = count;
 702                 release_sock(&jsk->sk);
 703                 kfree(ofilters);
 704                 return 0;
 705         case SO_J1939_PROMISC:
 706                 return j1939_sk_setsockopt_flag(jsk, optval, optlen,
 707                                                 J1939_SOCK_PROMISC);
 708         case SO_J1939_ERRQUEUE:
 709                 ret = j1939_sk_setsockopt_flag(jsk, optval, optlen,
 710                                                J1939_SOCK_ERRQUEUE);
 711                 if (ret < 0)
 712                         return ret;
 713
 714                 if (!(jsk->state & J1939_SOCK_ERRQUEUE))
 715                         skb_queue_purge(&sk->sk_error_queue);
 716                 return ret;
 717         case SO_J1939_SEND_PRIO:
 718                 if (optlen != sizeof(tmp))
 719                         return -EINVAL;
 720                 if (copy_from_sockptr(&tmp, optval, optlen))
 721                         return -EFAULT;
 722                 if (tmp < 0 || tmp > 7)
 723                         return -EDOM;
 724                 if (tmp < 2 && !capable(CAP_NET_ADMIN))
 725                         return -EPERM;
 726                 lock_sock(&jsk->sk);
 727                 jsk->sk.sk_priority = j1939_to_sk_priority(tmp);
 728                 release_sock(&jsk->sk);
 729                 return 0;
 730         default:
 731                 return -ENOPROTOOPT;
 732         }
 733 }
 734
 735 static int j1939_sk_getsockopt(struct socket *sock, int level, int optname,
 736                                char __user *optval, int __user *optlen)
 737 {
 738         struct sock *sk = sock->sk;
 739         struct j1939_sock *jsk = j1939_sk(sk);
 740         int ret, ulen;
 741         /* set defaults for using 'int' properties */
 742         int tmp = 0;
 743         int len = sizeof(tmp);
 744         void *val = &tmp;
 745
 746         if (level != SOL_CAN_J1939)
 747                 return -EINVAL;
 748         if (get_user(ulen, optlen))
 749                 return -EFAULT;
 750         if (ulen < 0)
 751                 return -EINVAL;
 752
 753         lock_sock(&jsk->sk);
 754         switch (optname) {
 755         case SO_J1939_PROMISC:
 756                 tmp = (jsk->state & J1939_SOCK_PROMISC) ? 1 : 0;
 757                 break;
 758         case SO_J1939_ERRQUEUE:
 759                 tmp = (jsk->state & J1939_SOCK_ERRQUEUE) ? 1 : 0;
 760                 break;
 761         case SO_J1939_SEND_PRIO:
 762                 tmp = j1939_prio(jsk->sk.sk_priority);
 763                 break;
 764         default:
 765                 ret = -ENOPROTOOPT;
 766                 goto no_copy;
 767         }
 768
 769         /* copy to user, based on 'len' & 'val'
 770          * but most sockopt's are 'int' properties, and have 'len' & 'val'
 771          * left unchanged, but instead modified 'tmp'
 772          */
 773         if (len > ulen)
 774                 ret = -EFAULT;
 775         else if (put_user(len, optlen))
 776                 ret = -EFAULT;
 777         else if (copy_to_user(optval, val, len))
 778                 ret = -EFAULT;
 779         else
 780                 ret = 0;
 781  no_copy:
 782         release_sock(&jsk->sk);
 783         return ret;
 784 }
 785
 786 static int j1939_sk_recvmsg(struct socket *sock, struct msghdr *msg,
 787                             size_t size, int flags)
 788 {
 789         struct sock *sk = sock->sk;
 790         struct sk_buff *skb;
 791         struct j1939_sk_buff_cb *skcb;
 792         int ret = 0;
 793
 794         if (flags & ~(MSG_DONTWAIT | MSG_ERRQUEUE))
 795                 return -EINVAL;
 796
 797         if (flags & MSG_ERRQUEUE)
 798                 return sock_recv_errqueue(sock->sk, msg, size, SOL_CAN_J1939,
 799                                           SCM_J1939_ERRQUEUE);
 800
 801         skb = skb_recv_datagram(sk, flags, 0, &ret);
 802         if (!skb)
 803                 return ret;
 804
 805         if (size < skb->len)
 806                 msg->msg_flags |= MSG_TRUNC;
 807         else
 808                 size = skb->len;
 809
 810         ret = memcpy_to_msg(msg, skb->data, size);
 811         if (ret < 0) {
 812                 skb_free_datagram(sk, skb);
 813                 return ret;
 814         }
 815
 816         skcb = j1939_skb_to_cb(skb);
 817         if (j1939_address_is_valid(skcb->addr.da))
 818                 put_cmsg(msg, SOL_CAN_J1939, SCM_J1939_DEST_ADDR,
 819                          sizeof(skcb->addr.da), &skcb->addr.da);
 820
 821         if (skcb->addr.dst_name)
 822                 put_cmsg(msg, SOL_CAN_J1939, SCM_J1939_DEST_NAME,
 823                          sizeof(skcb->addr.dst_name), &skcb->addr.dst_name);
 824
 825         put_cmsg(msg, SOL_CAN_J1939, SCM_J1939_PRIO,
 826                  sizeof(skcb->priority), &skcb->priority);
 827
 828         if (msg->msg_name) {
 829                 struct sockaddr_can *paddr = msg->msg_name;
 830
 831                 msg->msg_namelen = J1939_MIN_NAMELEN;
 832                 memset(msg->msg_name, 0, msg->msg_namelen);
 833                 paddr->can_family = AF_CAN;
 834                 paddr->can_ifindex = skb->skb_iif;
 835                 paddr->can_addr.j1939.name = skcb->addr.src_name;
 836                 paddr->can_addr.j1939.addr = skcb->addr.sa;
 837                 paddr->can_addr.j1939.pgn = skcb->addr.pgn;
 838         }
 839
 840         sock_recv_ts_and_drops(msg, sk, skb);
 841         msg->msg_flags |= skcb->msg_flags;
 842         skb_free_datagram(sk, skb);
 843
 844         return size;
 845 }
 846
 847 static struct sk_buff *j1939_sk_alloc_skb(struct net_device *ndev,
 848                                           struct sock *sk,
 849                                           struct msghdr *msg, size_t size,
 850                                           int *errcode)
 851 {
 852         struct j1939_sock *jsk = j1939_sk(sk);
 853         struct j1939_sk_buff_cb *skcb;
 854         struct sk_buff *skb;
 855         int ret;
 856
 857         skb = sock_alloc_send_skb(sk,
 858                                   size +
 859                                   sizeof(struct can_frame) -
 860                                   sizeof(((struct can_frame *)NULL)->data) +
 861                                   sizeof(struct can_skb_priv),
 862                                   msg->msg_flags & MSG_DONTWAIT, &ret);
 863         if (!skb)
 864                 goto failure;
 865
 866         can_skb_reserve(skb);
 867         can_skb_prv(skb)->ifindex = ndev->ifindex;
 868         can_skb_prv(skb)->skbcnt = 0;
 869         skb_reserve(skb, offsetof(struct can_frame, data));
 870
 871         ret = memcpy_from_msg(skb_put(skb, size), msg, size);
 872         if (ret < 0)
 873                 goto free_skb;
 874
 875         skb->dev = ndev;
 876
 877         skcb = j1939_skb_to_cb(skb);
 878         memset(skcb, 0, sizeof(*skcb));
 879         skcb->addr = jsk->addr;
 880         skcb->priority = j1939_prio(sk->sk_priority);
 881
 882         if (msg->msg_name) {
 883                 struct sockaddr_can *addr = msg->msg_name;
 884
 885                 if (addr->can_addr.j1939.name ||
 886                     addr->can_addr.j1939.addr != J1939_NO_ADDR) {
 887                         skcb->addr.dst_name = addr->can_addr.j1939.name;
 888                         skcb->addr.da = addr->can_addr.j1939.addr;
 889                 }
 890                 if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn))
 891                         skcb->addr.pgn = addr->can_addr.j1939.pgn;
 892         }
 893
 894         *errcode = ret;
 895         return skb;
 896
 897 free_skb:
 898         kfree_skb(skb);
 899 failure:
 900         *errcode = ret;
 901         return NULL;
 902 }
 903
 904 static size_t j1939_sk_opt_stats_get_size(void)
 905 {
 906         return
 907                 nla_total_size(sizeof(u32)) + /* J1939_NLA_BYTES_ACKED */
 908                 0;
 909 }
 910
 911 static struct sk_buff *
 912 j1939_sk_get_timestamping_opt_stats(struct j1939_session *session)
 913 {
 914         struct sk_buff *stats;
 915         u32 size;
 916
 917         stats = alloc_skb(j1939_sk_opt_stats_get_size(), GFP_ATOMIC);
 918         if (!stats)
 919                 return NULL;
 920
 921         if (session->skcb.addr.type == J1939_SIMPLE)
 922                 size = session->total_message_size;
 923         else
 924                 size = min(session->pkt.tx_acked * 7,
 925                            session->total_message_size);
 926
 927         nla_put_u32(stats, J1939_NLA_BYTES_ACKED, size);
 928
 929         return stats;
 930 }
 931
 932 void j1939_sk_errqueue(struct j1939_session *session,
 933                        enum j1939_sk_errqueue_type type)
 934 {
 935         struct j1939_priv *priv = session->priv;
 936         struct sock *sk = session->sk;
 937         struct j1939_sock *jsk;
 938         struct sock_exterr_skb *serr;
 939         struct sk_buff *skb;
 940         char *state = "UNK";
 941         int err;
 942
 943         /* currently we have no sk for the RX session */
 944         if (!sk)
 945                 return;
 946
 947         jsk = j1939_sk(sk);
 948
 949         if (!(jsk->state & J1939_SOCK_ERRQUEUE))
 950                 return;
 951
 952         skb = j1939_sk_get_timestamping_opt_stats(session);
 953         if (!skb)
 954                 return;
 955
 956         skb->tstamp = ktime_get_real();
 957
 958         BUILD_BUG_ON(sizeof(struct sock_exterr_skb) > sizeof(skb->cb));
 959
 960         serr = SKB_EXT_ERR(skb);
 961         memset(serr, 0, sizeof(*serr));
 962         switch (type) {
 963         case J1939_ERRQUEUE_ACK:
 964                 if (!(sk->sk_tsflags & SOF_TIMESTAMPING_TX_ACK)) {
 965                         kfree_skb(skb);
 966                         return;
 967                 }
 968
 969                 serr->ee.ee_errno = ENOMSG;
 970                 serr->ee.ee_origin = SO_EE_ORIGIN_TIMESTAMPING;
 971                 serr->ee.ee_info = SCM_TSTAMP_ACK;
 972                 state = "ACK";
 973                 break;
 974         case J1939_ERRQUEUE_SCHED:
 975                 if (!(sk->sk_tsflags & SOF_TIMESTAMPING_TX_SCHED)) {
 976                         kfree_skb(skb);
 977                         return;
 978                 }
 979
 980                 serr->ee.ee_errno = ENOMSG;
 981                 serr->ee.ee_origin = SO_EE_ORIGIN_TIMESTAMPING;
 982                 serr->ee.ee_info = SCM_TSTAMP_SCHED;
 983                 state = "SCH";
 984                 break;
 985         case J1939_ERRQUEUE_ABORT:
 986                 serr->ee.ee_errno = session->err;
 987                 serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
 988                 serr->ee.ee_info = J1939_EE_INFO_TX_ABORT;
 989                 state = "ABT";
 990                 break;
 991         default:
 992                 netdev_err(priv->ndev, "Unknown errqueue type %i\n", type);
 993         }
 994
 995         serr->opt_stats = true;
 996         if (sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)
 997                 serr->ee.ee_data = session->tskey;
 998
 999         netdev_dbg(session->priv->ndev, "%s: 0x%p tskey: %i, state: %s\n",
1000                    __func__, session, session->tskey, state);
1001         err = sock_queue_err_skb(sk, skb);
1002
1003         if (err)
1004                 kfree_skb(skb);
1005 };
1006
1007 void j1939_sk_send_loop_abort(struct sock *sk, int err)
1008 {
1009         sk->sk_err = err;
1010
1011         sk->sk_error_report(sk);
1012 }
1013
1014 static int j1939_sk_send_loop(struct j1939_priv *priv,  struct sock *sk,
1015                               struct msghdr *msg, size_t size)
1016
1017 {
1018         struct j1939_sock *jsk = j1939_sk(sk);
1019         struct j1939_session *session = j1939_sk_get_incomplete_session(jsk);
1020         struct sk_buff *skb;
1021         size_t segment_size, todo_size;
1022         int ret = 0;
1023
1024         if (session &&
1025             session->total_message_size != session->total_queued_size + size) {
1026                 j1939_session_put(session);
1027                 return -EIO;
1028         }
1029
1030         todo_size = size;
1031
1032         while (todo_size) {
1033                 struct j1939_sk_buff_cb *skcb;
1034
1035                 segment_size = min_t(size_t, J1939_MAX_TP_PACKET_SIZE,
1036                                      todo_size);
1037
1038                 /* Allocate skb for one segment */
1039                 skb = j1939_sk_alloc_skb(priv->ndev, sk, msg, segment_size,
1040                                          &ret);
1041                 if (ret)
1042                         break;
1043
1044                 skcb = j1939_skb_to_cb(skb);
1045
1046                 if (!session) {
1047                         /* at this point the size should be full size
1048                          * of the session
1049                          */
1050                         skcb->offset = 0;
1051                         session = j1939_tp_send(priv, skb, size);
1052                         if (IS_ERR(session)) {
1053                                 ret = PTR_ERR(session);
1054                                 goto kfree_skb;
1055                         }
1056                         if (j1939_sk_queue_session(session)) {
1057                                 /* try to activate session if we a
1058                                  * fist in the queue
1059                                  */
1060                                 if (!j1939_session_activate(session)) {
1061                                         j1939_tp_schedule_txtimer(session, 0);
1062                                 } else {
1063                                         ret = -EBUSY;
1064                                         session->err = ret;
1065                                         j1939_sk_queue_drop_all(priv, jsk,
1066                                                                 EBUSY);
1067                                         break;
1068                                 }
1069                         }
1070                 } else {
1071                         skcb->offset = session->total_queued_size;
1072                         j1939_session_skb_queue(session, skb);
1073                 }
1074
1075                 todo_size -= segment_size;
1076                 session->total_queued_size += segment_size;
1077         }
1078
1079         switch (ret) {
1080         case 0: /* OK */
1081                 if (todo_size)
1082                         netdev_warn(priv->ndev,
1083                                     "no error found and not completely queued?! %zu\n",
1084                                     todo_size);
1085                 ret = size;
1086                 break;
1087         case -ERESTARTSYS:
1088                 ret = -EINTR;
1089                 fallthrough;
1090         case -EAGAIN: /* OK */
1091                 if (todo_size != size)
1092                         ret = size - todo_size;
1093                 break;
1094         default: /* ERROR */
1095                 break;
1096         }
1097
1098         if (session)
1099                 j1939_session_put(session);
1100
1101         return ret;
1102
1103  kfree_skb:
1104         kfree_skb(skb);
1105         return ret;
1106 }
1107
1108 static int j1939_sk_sendmsg(struct socket *sock, struct msghdr *msg,
1109                             size_t size)
1110 {
1111         struct sock *sk = sock->sk;
1112         struct j1939_sock *jsk = j1939_sk(sk);
1113         struct j1939_priv *priv;
1114         int ifindex;
1115         int ret;
1116
1117         lock_sock(sock->sk);
1118         /* various socket state tests */
1119         if (!(jsk->state & J1939_SOCK_BOUND)) {
1120                 ret = -EBADFD;
1121                 goto sendmsg_done;
1122         }
1123
1124         priv = jsk->priv;
1125         ifindex = jsk->ifindex;
1126
1127         if (!jsk->addr.src_name && jsk->addr.sa == J1939_NO_ADDR) {
1128                 /* no source address assigned yet */
1129                 ret = -EBADFD;
1130                 goto sendmsg_done;
1131         }
1132
1133         /* deal with provided destination address info */
1134         if (msg->msg_name) {
1135                 struct sockaddr_can *addr = msg->msg_name;
1136
1137                 if (msg->msg_namelen < J1939_MIN_NAMELEN) {
1138                         ret = -EINVAL;
1139                         goto sendmsg_done;
1140                 }
1141
1142                 if (addr->can_family != AF_CAN) {
1143                         ret = -EINVAL;
1144                         goto sendmsg_done;
1145                 }
1146
1147                 if (addr->can_ifindex && addr->can_ifindex != ifindex) {
1148                         ret = -EBADFD;
1149                         goto sendmsg_done;
1150                 }
1151
1152                 if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn) &&
1153                     !j1939_pgn_is_clean_pdu(addr->can_addr.j1939.pgn)) {
1154                         ret = -EINVAL;
1155                         goto sendmsg_done;
1156                 }
1157
1158                 if (!addr->can_addr.j1939.name &&
1159                     addr->can_addr.j1939.addr == J1939_NO_ADDR &&
1160                     !sock_flag(sk, SOCK_BROADCAST)) {
1161                         /* broadcast, but SO_BROADCAST not set */
1162                         ret = -EACCES;
1163                         goto sendmsg_done;
1164                 }
1165         } else {
1166                 if (!jsk->addr.dst_name && jsk->addr.da == J1939_NO_ADDR &&
1167                     !sock_flag(sk, SOCK_BROADCAST)) {
1168                         /* broadcast, but SO_BROADCAST not set */
1169                         ret = -EACCES;
1170                         goto sendmsg_done;
1171                 }
1172         }
1173
1174         ret = j1939_sk_send_loop(priv, sk, msg, size);
1175
1176 sendmsg_done:
1177         release_sock(sock->sk);
1178
1179         return ret;
1180 }
1181
1182 void j1939_sk_netdev_event_netdown(struct j1939_priv *priv)
1183 {
1184         struct j1939_sock *jsk;
1185         int error_code = ENETDOWN;
1186
1187         spin_lock_bh(&priv->j1939_socks_lock);
1188         list_for_each_entry(jsk, &priv->j1939_socks, list) {
1189                 jsk->sk.sk_err = error_code;
1190                 if (!sock_flag(&jsk->sk, SOCK_DEAD))
1191                         jsk->sk.sk_error_report(&jsk->sk);
1192
1193                 j1939_sk_queue_drop_all(priv, jsk, error_code);
1194         }
1195         spin_unlock_bh(&priv->j1939_socks_lock);
1196 }
1197
1198 static int j1939_sk_no_ioctlcmd(struct socket *sock, unsigned int cmd,
1199                                 unsigned long arg)
1200 {
1201         /* no ioctls for socket layer -> hand it down to NIC layer */
1202         return -ENOIOCTLCMD;
1203 }
1204
1205 static const struct proto_ops j1939_ops = {
1206         .family = PF_CAN,
1207         .release = j1939_sk_release,
1208         .bind = j1939_sk_bind,
1209         .connect = j1939_sk_connect,
1210         .socketpair = sock_no_socketpair,
1211         .accept = sock_no_accept,
1212         .getname = j1939_sk_getname,
1213         .poll = datagram_poll,
1214         .ioctl = j1939_sk_no_ioctlcmd,
1215         .listen = sock_no_listen,
1216         .shutdown = sock_no_shutdown,
1217         .setsockopt = j1939_sk_setsockopt,
1218         .getsockopt = j1939_sk_getsockopt,
1219         .sendmsg = j1939_sk_sendmsg,
1220         .recvmsg = j1939_sk_recvmsg,
1221         .mmap = sock_no_mmap,
1222         .sendpage = sock_no_sendpage,
1223 };
1224
1225 static struct proto j1939_proto __read_mostly = {
1226         .name = "CAN_J1939",
1227         .owner = THIS_MODULE,
1228         .obj_size = sizeof(struct j1939_sock),
1229         .init = j1939_sk_init,
1230 };
1231
1232 const struct can_proto j1939_can_proto = {
1233         .type = SOCK_DGRAM,
1234         .protocol = CAN_J1939,
1235         .ops = &j1939_ops,
1236         .prot = &j1939_proto,
1237 };