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/can-ml.h>
  16 #include <linux/can/core.h>
  17 #include <linux/can/skb.h>
  18 #include <linux/errqueue.h>
  19 #include <linux/if_arp.h>
  20
  21 #include "j1939-priv.h"
  22
  23 #define J1939_MIN_NAMELEN CAN_REQUIRED_SIZE(struct sockaddr_can, can_addr.j1939)
  24
  25 /* conversion function between struct sock::sk_priority from linux and
  26  * j1939 priority field
  27  */
  28 static inline priority_t j1939_prio(u32 sk_priority)
  29 {
  30         sk_priority = min(sk_priority, 7U);
  31
  32         return 7 - sk_priority;
  33 }
  34
  35 static inline u32 j1939_to_sk_priority(priority_t prio)
  36 {
  37         return 7 - prio;
  38 }
  39
  40 /* function to see if pgn is to be evaluated */
  41 static inline bool j1939_pgn_is_valid(pgn_t pgn)
  42 {
  43         return pgn <= J1939_PGN_MAX;
  44 }
  45
  46 /* test function to avoid non-zero DA placeholder for pdu1 pgn's */
  47 static inline bool j1939_pgn_is_clean_pdu(pgn_t pgn)
  48 {
  49         if (j1939_pgn_is_pdu1(pgn))
  50                 return !(pgn & 0xff);
  51         else
  52                 return true;
  53 }
  54
  55 static inline void j1939_sock_pending_add(struct sock *sk)
  56 {
  57         struct j1939_sock *jsk = j1939_sk(sk);
  58
  59         atomic_inc(&jsk->skb_pending);
  60 }
  61
  62 static int j1939_sock_pending_get(struct sock *sk)
  63 {
  64         struct j1939_sock *jsk = j1939_sk(sk);
  65
  66         return atomic_read(&jsk->skb_pending);
  67 }
  68
  69 void j1939_sock_pending_del(struct sock *sk)
  70 {
  71         struct j1939_sock *jsk = j1939_sk(sk);
  72
  73         /* atomic_dec_return returns the new value */
  74         if (!atomic_dec_return(&jsk->skb_pending))
  75                 wake_up(&jsk->waitq);   /* no pending SKB's */
  76 }
  77
  78 static void j1939_jsk_add(struct j1939_priv *priv, struct j1939_sock *jsk)
  79 {
  80         jsk->state |= J1939_SOCK_BOUND;
  81         j1939_priv_get(priv);
  82
  83         spin_lock_bh(&priv->j1939_socks_lock);
  84         list_add_tail(&jsk->list, &priv->j1939_socks);
  85         spin_unlock_bh(&priv->j1939_socks_lock);
  86 }
  87
  88 static void j1939_jsk_del(struct j1939_priv *priv, struct j1939_sock *jsk)
  89 {
  90         spin_lock_bh(&priv->j1939_socks_lock);
  91         list_del_init(&jsk->list);
  92         spin_unlock_bh(&priv->j1939_socks_lock);
  93
  94         j1939_priv_put(priv);
  95         jsk->state &= ~J1939_SOCK_BOUND;
  96 }
  97
  98 static bool j1939_sk_queue_session(struct j1939_session *session)
  99 {
 100         struct j1939_sock *jsk = j1939_sk(session->sk);
 101         bool empty;
 102
 103         spin_lock_bh(&jsk->sk_session_queue_lock);
 104         empty = list_empty(&jsk->sk_session_queue);
 105         j1939_session_get(session);
 106         list_add_tail(&session->sk_session_queue_entry, &jsk->sk_session_queue);
 107         spin_unlock_bh(&jsk->sk_session_queue_lock);
 108         j1939_sock_pending_add(&jsk->sk);
 109
 110         return empty;
 111 }
 112
 113 static struct
 114 j1939_session *j1939_sk_get_incomplete_session(struct j1939_sock *jsk)
 115 {
 116         struct j1939_session *session = NULL;
 117
 118         spin_lock_bh(&jsk->sk_session_queue_lock);
 119         if (!list_empty(&jsk->sk_session_queue)) {
 120                 session = list_last_entry(&jsk->sk_session_queue,
 121                                           struct j1939_session,
 122                                           sk_session_queue_entry);
 123                 if (session->total_queued_size == session->total_message_size)
 124                         session = NULL;
 125                 else
 126                         j1939_session_get(session);
 127         }
 128         spin_unlock_bh(&jsk->sk_session_queue_lock);
 129
 130         return session;
 131 }
 132
 133 static void j1939_sk_queue_drop_all(struct j1939_priv *priv,
 134                                     struct j1939_sock *jsk, int err)
 135 {
 136         struct j1939_session *session, *tmp;
 137
 138         netdev_dbg(priv->ndev, "%s: err: %i\n", __func__, err);
 139         spin_lock_bh(&jsk->sk_session_queue_lock);
 140         list_for_each_entry_safe(session, tmp, &jsk->sk_session_queue,
 141                                  sk_session_queue_entry) {
 142                 list_del_init(&session->sk_session_queue_entry);
 143                 session->err = err;
 144                 j1939_session_put(session);
 145         }
 146         spin_unlock_bh(&jsk->sk_session_queue_lock);
 147 }
 148
 149 static void j1939_sk_queue_activate_next_locked(struct j1939_session *session)
 150 {
 151         struct j1939_sock *jsk;
 152         struct j1939_session *first;
 153         int err;
 154
 155         /* RX-Session don't have a socket (yet) */
 156         if (!session->sk)
 157                 return;
 158
 159         jsk = j1939_sk(session->sk);
 160         lockdep_assert_held(&jsk->sk_session_queue_lock);
 161
 162         err = session->err;
 163
 164         first = list_first_entry_or_null(&jsk->sk_session_queue,
 165                                          struct j1939_session,
 166                                          sk_session_queue_entry);
 167
 168         /* Some else has already activated the next session */
 169         if (first != session)
 170                 return;
 171
 172 activate_next:
 173         list_del_init(&first->sk_session_queue_entry);
 174         j1939_session_put(first);
 175         first = list_first_entry_or_null(&jsk->sk_session_queue,
 176                                          struct j1939_session,
 177                                          sk_session_queue_entry);
 178         if (!first)
 179                 return;
 180
 181         if (WARN_ON_ONCE(j1939_session_activate(first))) {
 182                 first->err = -EBUSY;
 183                 goto activate_next;
 184         } else {
 185                 /* Give receiver some time (arbitrary chosen) to recover */
 186                 int time_ms = 0;
 187
 188                 if (err)
 189                         time_ms = 10 + prandom_u32_max(16);
 190
 191                 j1939_tp_schedule_txtimer(first, time_ms);
 192         }
 193 }
 194
 195 void j1939_sk_queue_activate_next(struct j1939_session *session)
 196 {
 197         struct j1939_sock *jsk;
 198
 199         if (!session->sk)
 200                 return;
 201
 202         jsk = j1939_sk(session->sk);
 203
 204         spin_lock_bh(&jsk->sk_session_queue_lock);
 205         j1939_sk_queue_activate_next_locked(session);
 206         spin_unlock_bh(&jsk->sk_session_queue_lock);
 207 }
 208
 209 static bool j1939_sk_match_dst(struct j1939_sock *jsk,
 210                                const struct j1939_sk_buff_cb *skcb)
 211 {
 212         if ((jsk->state & J1939_SOCK_PROMISC))
 213                 return true;
 214
 215         /* Destination address filter */
 216         if (jsk->addr.src_name && skcb->addr.dst_name) {
 217                 if (jsk->addr.src_name != skcb->addr.dst_name)
 218                         return false;
 219         } else {
 220                 /* receive (all sockets) if
 221                  * - all packages that match our bind() address
 222                  * - all broadcast on a socket if SO_BROADCAST
 223                  *   is set
 224                  */
 225                 if (j1939_address_is_unicast(skcb->addr.da)) {
 226                         if (jsk->addr.sa != skcb->addr.da)
 227                                 return false;
 228                 } else if (!sock_flag(&jsk->sk, SOCK_BROADCAST)) {
 229                         /* receiving broadcast without SO_BROADCAST
 230                          * flag is not allowed
 231                          */
 232                         return false;
 233                 }
 234         }
 235
 236         /* Source address filter */
 237         if (jsk->state & J1939_SOCK_CONNECTED) {
 238                 /* receive (all sockets) if
 239                  * - all packages that match our connect() name or address
 240                  */
 241                 if (jsk->addr.dst_name && skcb->addr.src_name) {
 242                         if (jsk->addr.dst_name != skcb->addr.src_name)
 243                                 return false;
 244                 } else {
 245                         if (jsk->addr.da != skcb->addr.sa)
 246                                 return false;
 247                 }
 248         }
 249
 250         /* PGN filter */
 251         if (j1939_pgn_is_valid(jsk->pgn_rx_filter) &&
 252             jsk->pgn_rx_filter != skcb->addr.pgn)
 253                 return false;
 254
 255         return true;
 256 }
 257
 258 /* matches skb control buffer (addr) with a j1939 filter */
 259 static bool j1939_sk_match_filter(struct j1939_sock *jsk,
 260                                   const struct j1939_sk_buff_cb *skcb)
 261 {
 262         const struct j1939_filter *f = jsk->filters;
 263         int nfilter = jsk->nfilters;
 264
 265         if (!nfilter)
 266                 /* receive all when no filters are assigned */
 267                 return true;
 268
 269         for (; nfilter; ++f, --nfilter) {
 270                 if ((skcb->addr.pgn & f->pgn_mask) != f->pgn)
 271                         continue;
 272                 if ((skcb->addr.sa & f->addr_mask) != f->addr)
 273                         continue;
 274                 if ((skcb->addr.src_name & f->name_mask) != f->name)
 275                         continue;
 276                 return true;
 277         }
 278         return false;
 279 }
 280
 281 static bool j1939_sk_recv_match_one(struct j1939_sock *jsk,
 282                                     const struct j1939_sk_buff_cb *skcb)
 283 {
 284         if (!(jsk->state & J1939_SOCK_BOUND))
 285                 return false;
 286
 287         if (!j1939_sk_match_dst(jsk, skcb))
 288                 return false;
 289
 290         if (!j1939_sk_match_filter(jsk, skcb))
 291                 return false;
 292
 293         return true;
 294 }
 295
 296 static void j1939_sk_recv_one(struct j1939_sock *jsk, struct sk_buff *oskb)
 297 {
 298         const struct j1939_sk_buff_cb *oskcb = j1939_skb_to_cb(oskb);
 299         struct j1939_sk_buff_cb *skcb;
 300         struct sk_buff *skb;
 301
 302         if (oskb->sk == &jsk->sk)
 303                 return;
 304
 305         if (!j1939_sk_recv_match_one(jsk, oskcb))
 306                 return;
 307
 308         skb = skb_clone(oskb, GFP_ATOMIC);
 309         if (!skb) {
 310                 pr_warn("skb clone failed\n");
 311                 return;
 312         }
 313         can_skb_set_owner(skb, oskb->sk);
 314
 315         skcb = j1939_skb_to_cb(skb);
 316         skcb->msg_flags &= ~(MSG_DONTROUTE);
 317         if (skb->sk)
 318                 skcb->msg_flags |= MSG_DONTROUTE;
 319
 320         if (sock_queue_rcv_skb(&jsk->sk, skb) < 0)
 321                 kfree_skb(skb);
 322 }
 323
 324 bool j1939_sk_recv_match(struct j1939_priv *priv, struct j1939_sk_buff_cb *skcb)
 325 {
 326         struct j1939_sock *jsk;
 327         bool match = false;
 328
 329         spin_lock_bh(&priv->j1939_socks_lock);
 330         list_for_each_entry(jsk, &priv->j1939_socks, list) {
 331                 match = j1939_sk_recv_match_one(jsk, skcb);
 332                 if (match)
 333                         break;
 334         }
 335         spin_unlock_bh(&priv->j1939_socks_lock);
 336
 337         return match;
 338 }
 339
 340 void j1939_sk_recv(struct j1939_priv *priv, struct sk_buff *skb)
 341 {
 342         struct j1939_sock *jsk;
 343
 344         spin_lock_bh(&priv->j1939_socks_lock);
 345         list_for_each_entry(jsk, &priv->j1939_socks, list) {
 346                 j1939_sk_recv_one(jsk, skb);
 347         }
 348         spin_unlock_bh(&priv->j1939_socks_lock);
 349 }
 350
 351 static void j1939_sk_sock_destruct(struct sock *sk)
 352 {
 353         struct j1939_sock *jsk = j1939_sk(sk);
 354
 355         /* This function will be call by the generic networking code, when then
 356          * the socket is ultimately closed (sk->sk_destruct).
 357          *
 358          * The race between
 359          * - processing a received CAN frame
 360          *   (can_receive -> j1939_can_recv)
 361          *   and accessing j1939_priv
 362          * ... and ...
 363          * - closing a socket
 364          *   (j1939_can_rx_unregister -> can_rx_unregister)
 365          *   and calling the final j1939_priv_put()
 366          *
 367          * is avoided by calling the final j1939_priv_put() from this
 368          * RCU deferred cleanup call.
 369          */
 370         if (jsk->priv) {
 371                 j1939_priv_put(jsk->priv);
 372                 jsk->priv = NULL;
 373         }
 374
 375         /* call generic CAN sock destruct */
 376         can_sock_destruct(sk);
 377 }
 378
 379 static int j1939_sk_init(struct sock *sk)
 380 {
 381         struct j1939_sock *jsk = j1939_sk(sk);
 382
 383         /* Ensure that "sk" is first member in "struct j1939_sock", so that we
 384          * can skip it during memset().
 385          */
 386         BUILD_BUG_ON(offsetof(struct j1939_sock, sk) != 0);
 387         memset((void *)jsk + sizeof(jsk->sk), 0x0,
 388                sizeof(*jsk) - sizeof(jsk->sk));
 389
 390         INIT_LIST_HEAD(&jsk->list);
 391         init_waitqueue_head(&jsk->waitq);
 392         jsk->sk.sk_priority = j1939_to_sk_priority(6);
 393         jsk->sk.sk_reuse = 1; /* per default */
 394         jsk->addr.sa = J1939_NO_ADDR;
 395         jsk->addr.da = J1939_NO_ADDR;
 396         jsk->addr.pgn = J1939_NO_PGN;
 397         jsk->pgn_rx_filter = J1939_NO_PGN;
 398         atomic_set(&jsk->skb_pending, 0);
 399         spin_lock_init(&jsk->sk_session_queue_lock);
 400         INIT_LIST_HEAD(&jsk->sk_session_queue);
 401         sk->sk_destruct = j1939_sk_sock_destruct;
 402         sk->sk_protocol = CAN_J1939;
 403
 404         return 0;
 405 }
 406
 407 static int j1939_sk_sanity_check(struct sockaddr_can *addr, int len)
 408 {
 409         if (!addr)
 410                 return -EDESTADDRREQ;
 411         if (len < J1939_MIN_NAMELEN)
 412                 return -EINVAL;
 413         if (addr->can_family != AF_CAN)
 414                 return -EINVAL;
 415         if (!addr->can_ifindex)
 416                 return -ENODEV;
 417         if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn) &&
 418             !j1939_pgn_is_clean_pdu(addr->can_addr.j1939.pgn))
 419                 return -EINVAL;
 420
 421         return 0;
 422 }
 423
 424 static int j1939_sk_bind(struct socket *sock, struct sockaddr *uaddr, int len)
 425 {
 426         struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
 427         struct j1939_sock *jsk = j1939_sk(sock->sk);
 428         struct j1939_priv *priv;
 429         struct sock *sk;
 430         struct net *net;
 431         int ret = 0;
 432
 433         ret = j1939_sk_sanity_check(addr, len);
 434         if (ret)
 435                 return ret;
 436
 437         lock_sock(sock->sk);
 438
 439         priv = jsk->priv;
 440         sk = sock->sk;
 441         net = sock_net(sk);
 442
 443         /* Already bound to an interface? */
 444         if (jsk->state & J1939_SOCK_BOUND) {
 445                 /* A re-bind() to a different interface is not
 446                  * supported.
 447                  */
 448                 if (jsk->ifindex != addr->can_ifindex) {
 449                         ret = -EINVAL;
 450                         goto out_release_sock;
 451                 }
 452
 453                 /* drop old references */
 454                 j1939_jsk_del(priv, jsk);
 455                 j1939_local_ecu_put(priv, jsk->addr.src_name, jsk->addr.sa);
 456         } else {
 457                 struct can_ml_priv *can_ml;
 458                 struct net_device *ndev;
 459
 460                 ndev = dev_get_by_index(net, addr->can_ifindex);
 461                 if (!ndev) {
 462                         ret = -ENODEV;
 463                         goto out_release_sock;
 464                 }
 465
 466                 can_ml = can_get_ml_priv(ndev);
 467                 if (!can_ml) {
 468                         dev_put(ndev);
 469                         ret = -ENODEV;
 470                         goto out_release_sock;
 471                 }
 472
 473                 if (!(ndev->flags & IFF_UP)) {
 474                         dev_put(ndev);
 475                         ret = -ENETDOWN;
 476                         goto out_release_sock;
 477                 }
 478
 479                 priv = j1939_netdev_start(ndev);
 480                 dev_put(ndev);
 481                 if (IS_ERR(priv)) {
 482                         ret = PTR_ERR(priv);
 483                         goto out_release_sock;
 484                 }
 485
 486                 jsk->ifindex = addr->can_ifindex;
 487
 488                 /* the corresponding j1939_priv_put() is called via
 489                  * sk->sk_destruct, which points to j1939_sk_sock_destruct()
 490                  */
 491                 j1939_priv_get(priv);
 492                 jsk->priv = priv;
 493         }
 494
 495         /* set default transmit pgn */
 496         if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn))
 497                 jsk->pgn_rx_filter = addr->can_addr.j1939.pgn;
 498         jsk->addr.src_name = addr->can_addr.j1939.name;
 499         jsk->addr.sa = addr->can_addr.j1939.addr;
 500
 501         /* get new references */
 502         ret = j1939_local_ecu_get(priv, jsk->addr.src_name, jsk->addr.sa);
 503         if (ret) {
 504                 j1939_netdev_stop(priv);
 505                 goto out_release_sock;
 506         }
 507
 508         j1939_jsk_add(priv, jsk);
 509
 510  out_release_sock: /* fall through */
 511         release_sock(sock->sk);
 512
 513         return ret;
 514 }
 515
 516 static int j1939_sk_connect(struct socket *sock, struct sockaddr *uaddr,
 517                             int len, int flags)
 518 {
 519         struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
 520         struct j1939_sock *jsk = j1939_sk(sock->sk);
 521         int ret = 0;
 522
 523         ret = j1939_sk_sanity_check(addr, len);
 524         if (ret)
 525                 return ret;
 526
 527         lock_sock(sock->sk);
 528
 529         /* bind() before connect() is mandatory */
 530         if (!(jsk->state & J1939_SOCK_BOUND)) {
 531                 ret = -EINVAL;
 532                 goto out_release_sock;
 533         }
 534
 535         /* A connect() to a different interface is not supported. */
 536         if (jsk->ifindex != addr->can_ifindex) {
 537                 ret = -EINVAL;
 538                 goto out_release_sock;
 539         }
 540
 541         if (!addr->can_addr.j1939.name &&
 542             addr->can_addr.j1939.addr == J1939_NO_ADDR &&
 543             !sock_flag(&jsk->sk, SOCK_BROADCAST)) {
 544                 /* broadcast, but SO_BROADCAST not set */
 545                 ret = -EACCES;
 546                 goto out_release_sock;
 547         }
 548
 549         jsk->addr.dst_name = addr->can_addr.j1939.name;
 550         jsk->addr.da = addr->can_addr.j1939.addr;
 551
 552         if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn))
 553                 jsk->addr.pgn = addr->can_addr.j1939.pgn;
 554
 555         jsk->state |= J1939_SOCK_CONNECTED;
 556
 557  out_release_sock: /* fall through */
 558         release_sock(sock->sk);
 559
 560         return ret;
 561 }
 562
 563 static void j1939_sk_sock2sockaddr_can(struct sockaddr_can *addr,
 564                                        const struct j1939_sock *jsk, int peer)
 565 {
 566         /* There are two holes (2 bytes and 3 bytes) to clear to avoid
 567          * leaking kernel information to user space.
 568          */
 569         memset(addr, 0, J1939_MIN_NAMELEN);
 570
 571         addr->can_family = AF_CAN;
 572         addr->can_ifindex = jsk->ifindex;
 573         addr->can_addr.j1939.pgn = jsk->addr.pgn;
 574         if (peer) {
 575                 addr->can_addr.j1939.name = jsk->addr.dst_name;
 576                 addr->can_addr.j1939.addr = jsk->addr.da;
 577         } else {
 578                 addr->can_addr.j1939.name = jsk->addr.src_name;
 579                 addr->can_addr.j1939.addr = jsk->addr.sa;
 580         }
 581 }
 582
 583 static int j1939_sk_getname(struct socket *sock, struct sockaddr *uaddr,
 584                             int peer)
 585 {
 586         struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
 587         struct sock *sk = sock->sk;
 588         struct j1939_sock *jsk = j1939_sk(sk);
 589         int ret = 0;
 590
 591         lock_sock(sk);
 592
 593         if (peer && !(jsk->state & J1939_SOCK_CONNECTED)) {
 594                 ret = -EADDRNOTAVAIL;
 595                 goto failure;
 596         }
 597
 598         j1939_sk_sock2sockaddr_can(addr, jsk, peer);
 599         ret = J1939_MIN_NAMELEN;
 600
 601  failure:
 602         release_sock(sk);
 603
 604         return ret;
 605 }
 606
 607 static int j1939_sk_release(struct socket *sock)
 608 {
 609         struct sock *sk = sock->sk;
 610         struct j1939_sock *jsk;
 611
 612         if (!sk)
 613                 return 0;
 614
 615         lock_sock(sk);
 616         jsk = j1939_sk(sk);
 617
 618         if (jsk->state & J1939_SOCK_BOUND) {
 619                 struct j1939_priv *priv = jsk->priv;
 620
 621                 if (wait_event_interruptible(jsk->waitq,
 622                                              !j1939_sock_pending_get(&jsk->sk))) {
 623                         j1939_cancel_active_session(priv, sk);
 624                         j1939_sk_queue_drop_all(priv, jsk, ESHUTDOWN);
 625                 }
 626
 627                 j1939_jsk_del(priv, jsk);
 628
 629                 j1939_local_ecu_put(priv, jsk->addr.src_name,
 630                                     jsk->addr.sa);
 631
 632                 j1939_netdev_stop(priv);
 633         }
 634
 635         kfree(jsk->filters);
 636         sock_orphan(sk);
 637         sock->sk = NULL;
 638
 639         release_sock(sk);
 640         sock_put(sk);
 641
 642         return 0;
 643 }
 644
 645 static int j1939_sk_setsockopt_flag(struct j1939_sock *jsk, sockptr_t optval,
 646                                     unsigned int optlen, int flag)
 647 {
 648         int tmp;
 649
 650         if (optlen != sizeof(tmp))
 651                 return -EINVAL;
 652         if (copy_from_sockptr(&tmp, optval, optlen))
 653                 return -EFAULT;
 654         lock_sock(&jsk->sk);
 655         if (tmp)
 656                 jsk->state |= flag;
 657         else
 658                 jsk->state &= ~flag;
 659         release_sock(&jsk->sk);
 660         return tmp;
 661 }
 662
 663 static int j1939_sk_setsockopt(struct socket *sock, int level, int optname,
 664                                sockptr_t optval, unsigned int optlen)
 665 {
 666         struct sock *sk = sock->sk;
 667         struct j1939_sock *jsk = j1939_sk(sk);
 668         int tmp, count = 0, ret = 0;
 669         struct j1939_filter *filters = NULL, *ofilters;
 670
 671         if (level != SOL_CAN_J1939)
 672                 return -EINVAL;
 673
 674         switch (optname) {
 675         case SO_J1939_FILTER:
 676                 if (!sockptr_is_null(optval)) {
 677                         struct j1939_filter *f;
 678                         int c;
 679
 680                         if (optlen % sizeof(*filters) != 0)
 681                                 return -EINVAL;
 682
 683                         if (optlen > J1939_FILTER_MAX *
 684                             sizeof(struct j1939_filter))
 685                                 return -EINVAL;
 686
 687                         count = optlen / sizeof(*filters);
 688                         filters = memdup_sockptr(optval, optlen);
 689                         if (IS_ERR(filters))
 690                                 return PTR_ERR(filters);
 691
 692                         for (f = filters, c = count; c; f++, c--) {
 693                                 f->name &= f->name_mask;
 694                                 f->pgn &= f->pgn_mask;
 695                                 f->addr &= f->addr_mask;
 696                         }
 697                 }
 698
 699                 lock_sock(&jsk->sk);
 700                 ofilters = jsk->filters;
 701                 jsk->filters = filters;
 702                 jsk->nfilters = count;
 703                 release_sock(&jsk->sk);
 704                 kfree(ofilters);
 705                 return 0;
 706         case SO_J1939_PROMISC:
 707                 return j1939_sk_setsockopt_flag(jsk, optval, optlen,
 708                                                 J1939_SOCK_PROMISC);
 709         case SO_J1939_ERRQUEUE:
 710                 ret = j1939_sk_setsockopt_flag(jsk, optval, optlen,
 711                                                J1939_SOCK_ERRQUEUE);
 712                 if (ret < 0)
 713                         return ret;
 714
 715                 if (!(jsk->state & J1939_SOCK_ERRQUEUE))
 716                         skb_queue_purge(&sk->sk_error_queue);
 717                 return ret;
 718         case SO_J1939_SEND_PRIO:
 719                 if (optlen != sizeof(tmp))
 720                         return -EINVAL;
 721                 if (copy_from_sockptr(&tmp, optval, optlen))
 722                         return -EFAULT;
 723                 if (tmp < 0 || tmp > 7)
 724                         return -EDOM;
 725                 if (tmp < 2 && !capable(CAP_NET_ADMIN))
 726                         return -EPERM;
 727                 lock_sock(&jsk->sk);
 728                 jsk->sk.sk_priority = j1939_to_sk_priority(tmp);
 729                 release_sock(&jsk->sk);
 730                 return 0;
 731         default:
 732                 return -ENOPROTOOPT;
 733         }
 734 }
 735
 736 static int j1939_sk_getsockopt(struct socket *sock, int level, int optname,
 737                                char __user *optval, int __user *optlen)
 738 {
 739         struct sock *sk = sock->sk;
 740         struct j1939_sock *jsk = j1939_sk(sk);
 741         int ret, ulen;
 742         /* set defaults for using 'int' properties */
 743         int tmp = 0;
 744         int len = sizeof(tmp);
 745         void *val = &tmp;
 746
 747         if (level != SOL_CAN_J1939)
 748                 return -EINVAL;
 749         if (get_user(ulen, optlen))
 750                 return -EFAULT;
 751         if (ulen < 0)
 752                 return -EINVAL;
 753
 754         lock_sock(&jsk->sk);
 755         switch (optname) {
 756         case SO_J1939_PROMISC:
 757                 tmp = (jsk->state & J1939_SOCK_PROMISC) ? 1 : 0;
 758                 break;
 759         case SO_J1939_ERRQUEUE:
 760                 tmp = (jsk->state & J1939_SOCK_ERRQUEUE) ? 1 : 0;
 761                 break;
 762         case SO_J1939_SEND_PRIO:
 763                 tmp = j1939_prio(jsk->sk.sk_priority);
 764                 break;
 765         default:
 766                 ret = -ENOPROTOOPT;
 767                 goto no_copy;
 768         }
 769
 770         /* copy to user, based on 'len' & 'val'
 771          * but most sockopt's are 'int' properties, and have 'len' & 'val'
 772          * left unchanged, but instead modified 'tmp'
 773          */
 774         if (len > ulen)
 775                 ret = -EFAULT;
 776         else if (put_user(len, optlen))
 777                 ret = -EFAULT;
 778         else if (copy_to_user(optval, val, len))
 779                 ret = -EFAULT;
 780         else
 781                 ret = 0;
 782  no_copy:
 783         release_sock(&jsk->sk);
 784         return ret;
 785 }
 786
 787 static int j1939_sk_recvmsg(struct socket *sock, struct msghdr *msg,
 788                             size_t size, int flags)
 789 {
 790         struct sock *sk = sock->sk;
 791         struct sk_buff *skb;
 792         struct j1939_sk_buff_cb *skcb;
 793         int ret = 0;
 794
 795         if (flags & ~(MSG_DONTWAIT | MSG_ERRQUEUE))
 796                 return -EINVAL;
 797
 798         if (flags & MSG_ERRQUEUE)
 799                 return sock_recv_errqueue(sock->sk, msg, size, SOL_CAN_J1939,
 800                                           SCM_J1939_ERRQUEUE);
 801
 802         skb = skb_recv_datagram(sk, flags, 0, &ret);
 803         if (!skb)
 804                 return ret;
 805
 806         if (size < skb->len)
 807                 msg->msg_flags |= MSG_TRUNC;
 808         else
 809                 size = skb->len;
 810
 811         ret = memcpy_to_msg(msg, skb->data, size);
 812         if (ret < 0) {
 813                 skb_free_datagram(sk, skb);
 814                 return ret;
 815         }
 816
 817         skcb = j1939_skb_to_cb(skb);
 818         if (j1939_address_is_valid(skcb->addr.da))
 819                 put_cmsg(msg, SOL_CAN_J1939, SCM_J1939_DEST_ADDR,
 820                          sizeof(skcb->addr.da), &skcb->addr.da);
 821
 822         if (skcb->addr.dst_name)
 823                 put_cmsg(msg, SOL_CAN_J1939, SCM_J1939_DEST_NAME,
 824                          sizeof(skcb->addr.dst_name), &skcb->addr.dst_name);
 825
 826         put_cmsg(msg, SOL_CAN_J1939, SCM_J1939_PRIO,
 827                  sizeof(skcb->priority), &skcb->priority);
 828
 829         if (msg->msg_name) {
 830                 struct sockaddr_can *paddr = msg->msg_name;
 831
 832                 msg->msg_namelen = J1939_MIN_NAMELEN;
 833                 memset(msg->msg_name, 0, msg->msg_namelen);
 834                 paddr->can_family = AF_CAN;
 835                 paddr->can_ifindex = skb->skb_iif;
 836                 paddr->can_addr.j1939.name = skcb->addr.src_name;
 837                 paddr->can_addr.j1939.addr = skcb->addr.sa;
 838                 paddr->can_addr.j1939.pgn = skcb->addr.pgn;
 839         }
 840
 841         sock_recv_ts_and_drops(msg, sk, skb);
 842         msg->msg_flags |= skcb->msg_flags;
 843         skb_free_datagram(sk, skb);
 844
 845         return size;
 846 }
 847
 848 static struct sk_buff *j1939_sk_alloc_skb(struct net_device *ndev,
 849                                           struct sock *sk,
 850                                           struct msghdr *msg, size_t size,
 851                                           int *errcode)
 852 {
 853         struct j1939_sock *jsk = j1939_sk(sk);
 854         struct j1939_sk_buff_cb *skcb;
 855         struct sk_buff *skb;
 856         int ret;
 857
 858         skb = sock_alloc_send_skb(sk,
 859                                   size +
 860                                   sizeof(struct can_frame) -
 861                                   sizeof(((struct can_frame *)NULL)->data) +
 862                                   sizeof(struct can_skb_priv),
 863                                   msg->msg_flags & MSG_DONTWAIT, &ret);
 864         if (!skb)
 865                 goto failure;
 866
 867         can_skb_reserve(skb);
 868         can_skb_prv(skb)->ifindex = ndev->ifindex;
 869         can_skb_prv(skb)->skbcnt = 0;
 870         skb_reserve(skb, offsetof(struct can_frame, data));
 871
 872         ret = memcpy_from_msg(skb_put(skb, size), msg, size);
 873         if (ret < 0)
 874                 goto free_skb;
 875
 876         skb->dev = ndev;
 877
 878         skcb = j1939_skb_to_cb(skb);
 879         memset(skcb, 0, sizeof(*skcb));
 880         skcb->addr = jsk->addr;
 881         skcb->priority = j1939_prio(sk->sk_priority);
 882
 883         if (msg->msg_name) {
 884                 struct sockaddr_can *addr = msg->msg_name;
 885
 886                 if (addr->can_addr.j1939.name ||
 887                     addr->can_addr.j1939.addr != J1939_NO_ADDR) {
 888                         skcb->addr.dst_name = addr->can_addr.j1939.name;
 889                         skcb->addr.da = addr->can_addr.j1939.addr;
 890                 }
 891                 if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn))
 892                         skcb->addr.pgn = addr->can_addr.j1939.pgn;
 893         }
 894
 895         *errcode = ret;
 896         return skb;
 897
 898 free_skb:
 899         kfree_skb(skb);
 900 failure:
 901         *errcode = ret;
 902         return NULL;
 903 }
 904
 905 static size_t j1939_sk_opt_stats_get_size(void)
 906 {
 907         return
 908                 nla_total_size(sizeof(u32)) + /* J1939_NLA_BYTES_ACKED */
 909                 0;
 910 }
 911
 912 static struct sk_buff *
 913 j1939_sk_get_timestamping_opt_stats(struct j1939_session *session)
 914 {
 915         struct sk_buff *stats;
 916         u32 size;
 917
 918         stats = alloc_skb(j1939_sk_opt_stats_get_size(), GFP_ATOMIC);
 919         if (!stats)
 920                 return NULL;
 921
 922         if (session->skcb.addr.type == J1939_SIMPLE)
 923                 size = session->total_message_size;
 924         else
 925                 size = min(session->pkt.tx_acked * 7,
 926                            session->total_message_size);
 927
 928         nla_put_u32(stats, J1939_NLA_BYTES_ACKED, size);
 929
 930         return stats;
 931 }
 932
 933 void j1939_sk_errqueue(struct j1939_session *session,
 934                        enum j1939_sk_errqueue_type type)
 935 {
 936         struct j1939_priv *priv = session->priv;
 937         struct sock *sk = session->sk;
 938         struct j1939_sock *jsk;
 939         struct sock_exterr_skb *serr;
 940         struct sk_buff *skb;
 941         char *state = "UNK";
 942         int err;
 943
 944         /* currently we have no sk for the RX session */
 945         if (!sk)
 946                 return;
 947
 948         jsk = j1939_sk(sk);
 949
 950         if (!(jsk->state & J1939_SOCK_ERRQUEUE))
 951                 return;
 952
 953         skb = j1939_sk_get_timestamping_opt_stats(session);
 954         if (!skb)
 955                 return;
 956
 957         skb->tstamp = ktime_get_real();
 958
 959         BUILD_BUG_ON(sizeof(struct sock_exterr_skb) > sizeof(skb->cb));
 960
 961         serr = SKB_EXT_ERR(skb);
 962         memset(serr, 0, sizeof(*serr));
 963         switch (type) {
 964         case J1939_ERRQUEUE_ACK:
 965                 if (!(sk->sk_tsflags & SOF_TIMESTAMPING_TX_ACK)) {
 966                         kfree_skb(skb);
 967                         return;
 968                 }
 969
 970                 serr->ee.ee_errno = ENOMSG;
 971                 serr->ee.ee_origin = SO_EE_ORIGIN_TIMESTAMPING;
 972                 serr->ee.ee_info = SCM_TSTAMP_ACK;
 973                 state = "ACK";
 974                 break;
 975         case J1939_ERRQUEUE_SCHED:
 976                 if (!(sk->sk_tsflags & SOF_TIMESTAMPING_TX_SCHED)) {
 977                         kfree_skb(skb);
 978                         return;
 979                 }
 980
 981                 serr->ee.ee_errno = ENOMSG;
 982                 serr->ee.ee_origin = SO_EE_ORIGIN_TIMESTAMPING;
 983                 serr->ee.ee_info = SCM_TSTAMP_SCHED;
 984                 state = "SCH";
 985                 break;
 986         case J1939_ERRQUEUE_ABORT:
 987                 serr->ee.ee_errno = session->err;
 988                 serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
 989                 serr->ee.ee_info = J1939_EE_INFO_TX_ABORT;
 990                 state = "ABT";
 991                 break;
 992         default:
 993                 netdev_err(priv->ndev, "Unknown errqueue type %i\n", type);
 994         }
 995
 996         serr->opt_stats = true;
 997         if (sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)
 998                 serr->ee.ee_data = session->tskey;
 999
1000         netdev_dbg(session->priv->ndev, "%s: 0x%p tskey: %i, state: %s\n",
1001                    __func__, session, session->tskey, state);
1002         err = sock_queue_err_skb(sk, skb);
1003
1004         if (err)
1005                 kfree_skb(skb);
1006 };
1007
1008 void j1939_sk_send_loop_abort(struct sock *sk, int err)
1009 {
1010         sk->sk_err = err;
1011
1012         sk->sk_error_report(sk);
1013 }
1014
1015 static int j1939_sk_send_loop(struct j1939_priv *priv,  struct sock *sk,
1016                               struct msghdr *msg, size_t size)
1017
1018 {
1019         struct j1939_sock *jsk = j1939_sk(sk);
1020         struct j1939_session *session = j1939_sk_get_incomplete_session(jsk);
1021         struct sk_buff *skb;
1022         size_t segment_size, todo_size;
1023         int ret = 0;
1024
1025         if (session &&
1026             session->total_message_size != session->total_queued_size + size) {
1027                 j1939_session_put(session);
1028                 return -EIO;
1029         }
1030
1031         todo_size = size;
1032
1033         while (todo_size) {
1034                 struct j1939_sk_buff_cb *skcb;
1035
1036                 segment_size = min_t(size_t, J1939_MAX_TP_PACKET_SIZE,
1037                                      todo_size);
1038
1039                 /* Allocate skb for one segment */
1040                 skb = j1939_sk_alloc_skb(priv->ndev, sk, msg, segment_size,
1041                                          &ret);
1042                 if (ret)
1043                         break;
1044
1045                 skcb = j1939_skb_to_cb(skb);
1046
1047                 if (!session) {
1048                         /* at this point the size should be full size
1049                          * of the session
1050                          */
1051                         skcb->offset = 0;
1052                         session = j1939_tp_send(priv, skb, size);
1053                         if (IS_ERR(session)) {
1054                                 ret = PTR_ERR(session);
1055                                 goto kfree_skb;
1056                         }
1057                         if (j1939_sk_queue_session(session)) {
1058                                 /* try to activate session if we a
1059                                  * fist in the queue
1060                                  */
1061                                 if (!j1939_session_activate(session)) {
1062                                         j1939_tp_schedule_txtimer(session, 0);
1063                                 } else {
1064                                         ret = -EBUSY;
1065                                         session->err = ret;
1066                                         j1939_sk_queue_drop_all(priv, jsk,
1067                                                                 EBUSY);
1068                                         break;
1069                                 }
1070                         }
1071                 } else {
1072                         skcb->offset = session->total_queued_size;
1073                         j1939_session_skb_queue(session, skb);
1074                 }
1075
1076                 todo_size -= segment_size;
1077                 session->total_queued_size += segment_size;
1078         }
1079
1080         switch (ret) {
1081         case 0: /* OK */
1082                 if (todo_size)
1083                         netdev_warn(priv->ndev,
1084                                     "no error found and not completely queued?! %zu\n",
1085                                     todo_size);
1086                 ret = size;
1087                 break;
1088         case -ERESTARTSYS:
1089                 ret = -EINTR;
1090                 fallthrough;
1091         case -EAGAIN: /* OK */
1092                 if (todo_size != size)
1093                         ret = size - todo_size;
1094                 break;
1095         default: /* ERROR */
1096                 break;
1097         }
1098
1099         if (session)
1100                 j1939_session_put(session);
1101
1102         return ret;
1103
1104  kfree_skb:
1105         kfree_skb(skb);
1106         return ret;
1107 }
1108
1109 static int j1939_sk_sendmsg(struct socket *sock, struct msghdr *msg,
1110                             size_t size)
1111 {
1112         struct sock *sk = sock->sk;
1113         struct j1939_sock *jsk = j1939_sk(sk);
1114         struct j1939_priv *priv;
1115         int ifindex;
1116         int ret;
1117
1118         lock_sock(sock->sk);
1119         /* various socket state tests */
1120         if (!(jsk->state & J1939_SOCK_BOUND)) {
1121                 ret = -EBADFD;
1122                 goto sendmsg_done;
1123         }
1124
1125         priv = jsk->priv;
1126         ifindex = jsk->ifindex;
1127
1128         if (!jsk->addr.src_name && jsk->addr.sa == J1939_NO_ADDR) {
1129                 /* no source address assigned yet */
1130                 ret = -EBADFD;
1131                 goto sendmsg_done;
1132         }
1133
1134         /* deal with provided destination address info */
1135         if (msg->msg_name) {
1136                 struct sockaddr_can *addr = msg->msg_name;
1137
1138                 if (msg->msg_namelen < J1939_MIN_NAMELEN) {
1139                         ret = -EINVAL;
1140                         goto sendmsg_done;
1141                 }
1142
1143                 if (addr->can_family != AF_CAN) {
1144                         ret = -EINVAL;
1145                         goto sendmsg_done;
1146                 }
1147
1148                 if (addr->can_ifindex && addr->can_ifindex != ifindex) {
1149                         ret = -EBADFD;
1150                         goto sendmsg_done;
1151                 }
1152
1153                 if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn) &&
1154                     !j1939_pgn_is_clean_pdu(addr->can_addr.j1939.pgn)) {
1155                         ret = -EINVAL;
1156                         goto sendmsg_done;
1157                 }
1158
1159                 if (!addr->can_addr.j1939.name &&
1160                     addr->can_addr.j1939.addr == J1939_NO_ADDR &&
1161                     !sock_flag(sk, SOCK_BROADCAST)) {
1162                         /* broadcast, but SO_BROADCAST not set */
1163                         ret = -EACCES;
1164                         goto sendmsg_done;
1165                 }
1166         } else {
1167                 if (!jsk->addr.dst_name && jsk->addr.da == J1939_NO_ADDR &&
1168                     !sock_flag(sk, SOCK_BROADCAST)) {
1169                         /* broadcast, but SO_BROADCAST not set */
1170                         ret = -EACCES;
1171                         goto sendmsg_done;
1172                 }
1173         }
1174
1175         ret = j1939_sk_send_loop(priv, sk, msg, size);
1176
1177 sendmsg_done:
1178         release_sock(sock->sk);
1179
1180         return ret;
1181 }
1182
1183 void j1939_sk_netdev_event_netdown(struct j1939_priv *priv)
1184 {
1185         struct j1939_sock *jsk;
1186         int error_code = ENETDOWN;
1187
1188         spin_lock_bh(&priv->j1939_socks_lock);
1189         list_for_each_entry(jsk, &priv->j1939_socks, list) {
1190                 jsk->sk.sk_err = error_code;
1191                 if (!sock_flag(&jsk->sk, SOCK_DEAD))
1192                         jsk->sk.sk_error_report(&jsk->sk);
1193
1194                 j1939_sk_queue_drop_all(priv, jsk, error_code);
1195         }
1196         spin_unlock_bh(&priv->j1939_socks_lock);
1197 }
1198
1199 static int j1939_sk_no_ioctlcmd(struct socket *sock, unsigned int cmd,
1200                                 unsigned long arg)
1201 {
1202         /* no ioctls for socket layer -> hand it down to NIC layer */
1203         return -ENOIOCTLCMD;
1204 }
1205
1206 static const struct proto_ops j1939_ops = {
1207         .family = PF_CAN,
1208         .release = j1939_sk_release,
1209         .bind = j1939_sk_bind,
1210         .connect = j1939_sk_connect,
1211         .socketpair = sock_no_socketpair,
1212         .accept = sock_no_accept,
1213         .getname = j1939_sk_getname,
1214         .poll = datagram_poll,
1215         .ioctl = j1939_sk_no_ioctlcmd,
1216         .listen = sock_no_listen,
1217         .shutdown = sock_no_shutdown,
1218         .setsockopt = j1939_sk_setsockopt,
1219         .getsockopt = j1939_sk_getsockopt,
1220         .sendmsg = j1939_sk_sendmsg,
1221         .recvmsg = j1939_sk_recvmsg,
1222         .mmap = sock_no_mmap,
1223         .sendpage = sock_no_sendpage,
1224 };
1225
1226 static struct proto j1939_proto __read_mostly = {
1227         .name = "CAN_J1939",
1228         .owner = THIS_MODULE,
1229         .obj_size = sizeof(struct j1939_sock),
1230         .init = j1939_sk_init,
1231 };
1232
1233 const struct can_proto j1939_can_proto = {
1234         .type = SOCK_DGRAM,
1235         .protocol = CAN_J1939,
1236         .ops = &j1939_ops,
1237         .prot = &j1939_proto,
1238 };