net/can/j1939/socket.c

/* [<][>][^][v][top][bottom][index][help] */
This source file includes following definitions.
j1939_prio
j1939_to_sk_priority
j1939_pgn_is_valid
j1939_pgn_is_clean_pdu
j1939_sock_pending_add
j1939_sock_pending_get
j1939_sock_pending_del
j1939_jsk_add
j1939_jsk_del
j1939_sk_queue_session
j1939_sk_get_incomplete_session
j1939_sk_queue_drop_all
j1939_sk_queue_activate_next_locked
j1939_sk_queue_activate_next
j1939_sk_match_dst
j1939_sk_match_filter
j1939_sk_recv_match_one
j1939_sk_recv_one
j1939_sk_recv_match
j1939_sk_recv
j1939_sk_sock_destruct
j1939_sk_init
j1939_sk_sanity_check
j1939_sk_bind
j1939_sk_connect
j1939_sk_sock2sockaddr_can
j1939_sk_getname
j1939_sk_release
j1939_sk_setsockopt_flag
j1939_sk_setsockopt
j1939_sk_getsockopt
j1939_sk_recvmsg
j1939_sk_alloc_skb
j1939_sk_opt_stats_get_size
j1939_sk_get_timestamping_opt_stats
j1939_sk_errqueue
j1939_sk_send_loop_abort
j1939_sk_send_loop
j1939_sk_sendmsg
j1939_sk_netdev_event_netdown
j1939_sk_no_ioctlcmd
   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 
 402         return 0;
 403 }
 404 
 405 static int j1939_sk_sanity_check(struct sockaddr_can *addr, int len)
 406 {
 407         if (!addr)
 408                 return -EDESTADDRREQ;
 409         if (len < J1939_MIN_NAMELEN)
 410                 return -EINVAL;
 411         if (addr->can_family != AF_CAN)
 412                 return -EINVAL;
 413         if (!addr->can_ifindex)
 414                 return -ENODEV;
 415         if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn) &&
 416             !j1939_pgn_is_clean_pdu(addr->can_addr.j1939.pgn))
 417                 return -EINVAL;
 418 
 419         return 0;
 420 }
 421 
 422 static int j1939_sk_bind(struct socket *sock, struct sockaddr *uaddr, int len)
 423 {
 424         struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
 425         struct j1939_sock *jsk = j1939_sk(sock->sk);
 426         struct j1939_priv *priv;
 427         struct sock *sk;
 428         struct net *net;
 429         int ret = 0;
 430 
 431         ret = j1939_sk_sanity_check(addr, len);
 432         if (ret)
 433                 return ret;
 434 
 435         lock_sock(sock->sk);
 436 
 437         priv = jsk->priv;
 438         sk = sock->sk;
 439         net = sock_net(sk);
 440 
 441         /* Already bound to an interface? */
 442         if (jsk->state & J1939_SOCK_BOUND) {
 443                 /* A re-bind() to a different interface is not
 444                  * supported.
 445                  */
 446                 if (jsk->ifindex != addr->can_ifindex) {
 447                         ret = -EINVAL;
 448                         goto out_release_sock;
 449                 }
 450 
 451                 /* drop old references */
 452                 j1939_jsk_del(priv, jsk);
 453                 j1939_local_ecu_put(priv, jsk->addr.src_name, jsk->addr.sa);
 454         } else {
 455                 struct net_device *ndev;
 456 
 457                 ndev = dev_get_by_index(net, addr->can_ifindex);
 458                 if (!ndev) {
 459                         ret = -ENODEV;
 460                         goto out_release_sock;
 461                 }
 462 
 463                 if (ndev->type != ARPHRD_CAN) {
 464                         dev_put(ndev);
 465                         ret = -ENODEV;
 466                         goto out_release_sock;
 467                 }
 468 
 469                 priv = j1939_netdev_start(ndev);
 470                 dev_put(ndev);
 471                 if (IS_ERR(priv)) {
 472                         ret = PTR_ERR(priv);
 473                         goto out_release_sock;
 474                 }
 475 
 476                 jsk->ifindex = addr->can_ifindex;
 477 
 478                 /* the corresponding j1939_priv_put() is called via
 479                  * sk->sk_destruct, which points to j1939_sk_sock_destruct()
 480                  */
 481                 j1939_priv_get(priv);
 482                 jsk->priv = priv;
 483         }
 484 
 485         /* set default transmit pgn */
 486         if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn))
 487                 jsk->pgn_rx_filter = addr->can_addr.j1939.pgn;
 488         jsk->addr.src_name = addr->can_addr.j1939.name;
 489         jsk->addr.sa = addr->can_addr.j1939.addr;
 490 
 491         /* get new references */
 492         ret = j1939_local_ecu_get(priv, jsk->addr.src_name, jsk->addr.sa);
 493         if (ret) {
 494                 j1939_netdev_stop(priv);
 495                 goto out_release_sock;
 496         }
 497 
 498         j1939_jsk_add(priv, jsk);
 499 
 500  out_release_sock: /* fall through */
 501         release_sock(sock->sk);
 502 
 503         return ret;
 504 }
 505 
 506 static int j1939_sk_connect(struct socket *sock, struct sockaddr *uaddr,
 507                             int len, int flags)
 508 {
 509         struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
 510         struct j1939_sock *jsk = j1939_sk(sock->sk);
 511         int ret = 0;
 512 
 513         ret = j1939_sk_sanity_check(addr, len);
 514         if (ret)
 515                 return ret;
 516 
 517         lock_sock(sock->sk);
 518 
 519         /* bind() before connect() is mandatory */
 520         if (!(jsk->state & J1939_SOCK_BOUND)) {
 521                 ret = -EINVAL;
 522                 goto out_release_sock;
 523         }
 524 
 525         /* A connect() to a different interface is not supported. */
 526         if (jsk->ifindex != addr->can_ifindex) {
 527                 ret = -EINVAL;
 528                 goto out_release_sock;
 529         }
 530 
 531         if (!addr->can_addr.j1939.name &&
 532             addr->can_addr.j1939.addr == J1939_NO_ADDR &&
 533             !sock_flag(&jsk->sk, SOCK_BROADCAST)) {
 534                 /* broadcast, but SO_BROADCAST not set */
 535                 ret = -EACCES;
 536                 goto out_release_sock;
 537         }
 538 
 539         jsk->addr.dst_name = addr->can_addr.j1939.name;
 540         jsk->addr.da = addr->can_addr.j1939.addr;
 541 
 542         if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn))
 543                 jsk->addr.pgn = addr->can_addr.j1939.pgn;
 544 
 545         jsk->state |= J1939_SOCK_CONNECTED;
 546 
 547  out_release_sock: /* fall through */
 548         release_sock(sock->sk);
 549 
 550         return ret;
 551 }
 552 
 553 static void j1939_sk_sock2sockaddr_can(struct sockaddr_can *addr,
 554                                        const struct j1939_sock *jsk, int peer)
 555 {
 556         addr->can_family = AF_CAN;
 557         addr->can_ifindex = jsk->ifindex;
 558         addr->can_addr.j1939.pgn = jsk->addr.pgn;
 559         if (peer) {
 560                 addr->can_addr.j1939.name = jsk->addr.dst_name;
 561                 addr->can_addr.j1939.addr = jsk->addr.da;
 562         } else {
 563                 addr->can_addr.j1939.name = jsk->addr.src_name;
 564                 addr->can_addr.j1939.addr = jsk->addr.sa;
 565         }
 566 }
 567 
 568 static int j1939_sk_getname(struct socket *sock, struct sockaddr *uaddr,
 569                             int peer)
 570 {
 571         struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
 572         struct sock *sk = sock->sk;
 573         struct j1939_sock *jsk = j1939_sk(sk);
 574         int ret = 0;
 575 
 576         lock_sock(sk);
 577 
 578         if (peer && !(jsk->state & J1939_SOCK_CONNECTED)) {
 579                 ret = -EADDRNOTAVAIL;
 580                 goto failure;
 581         }
 582 
 583         j1939_sk_sock2sockaddr_can(addr, jsk, peer);
 584         ret = J1939_MIN_NAMELEN;
 585 
 586  failure:
 587         release_sock(sk);
 588 
 589         return ret;
 590 }
 591 
 592 static int j1939_sk_release(struct socket *sock)
 593 {
 594         struct sock *sk = sock->sk;
 595         struct j1939_sock *jsk;
 596 
 597         if (!sk)
 598                 return 0;
 599 
 600         lock_sock(sk);
 601         jsk = j1939_sk(sk);
 602 
 603         if (jsk->state & J1939_SOCK_BOUND) {
 604                 struct j1939_priv *priv = jsk->priv;
 605 
 606                 if (wait_event_interruptible(jsk->waitq,
 607                                              !j1939_sock_pending_get(&jsk->sk))) {
 608                         j1939_cancel_active_session(priv, sk);
 609                         j1939_sk_queue_drop_all(priv, jsk, ESHUTDOWN);
 610                 }
 611 
 612                 j1939_jsk_del(priv, jsk);
 613 
 614                 j1939_local_ecu_put(priv, jsk->addr.src_name,
 615                                     jsk->addr.sa);
 616 
 617                 j1939_netdev_stop(priv);
 618         }
 619 
 620         kfree(jsk->filters);
 621         sock_orphan(sk);
 622         sock->sk = NULL;
 623 
 624         release_sock(sk);
 625         sock_put(sk);
 626 
 627         return 0;
 628 }
 629 
 630 static int j1939_sk_setsockopt_flag(struct j1939_sock *jsk, char __user *optval,
 631                                     unsigned int optlen, int flag)
 632 {
 633         int tmp;
 634 
 635         if (optlen != sizeof(tmp))
 636                 return -EINVAL;
 637         if (copy_from_user(&tmp, optval, optlen))
 638                 return -EFAULT;
 639         lock_sock(&jsk->sk);
 640         if (tmp)
 641                 jsk->state |= flag;
 642         else
 643                 jsk->state &= ~flag;
 644         release_sock(&jsk->sk);
 645         return tmp;
 646 }
 647 
 648 static int j1939_sk_setsockopt(struct socket *sock, int level, int optname,
 649                                char __user *optval, unsigned int optlen)
 650 {
 651         struct sock *sk = sock->sk;
 652         struct j1939_sock *jsk = j1939_sk(sk);
 653         int tmp, count = 0, ret = 0;
 654         struct j1939_filter *filters = NULL, *ofilters;
 655 
 656         if (level != SOL_CAN_J1939)
 657                 return -EINVAL;
 658 
 659         switch (optname) {
 660         case SO_J1939_FILTER:
 661                 if (optval) {
 662                         struct j1939_filter *f;
 663                         int c;
 664 
 665                         if (optlen % sizeof(*filters) != 0)
 666                                 return -EINVAL;
 667 
 668                         if (optlen > J1939_FILTER_MAX *
 669                             sizeof(struct j1939_filter))
 670                                 return -EINVAL;
 671 
 672                         count = optlen / sizeof(*filters);
 673                         filters = memdup_user(optval, optlen);
 674                         if (IS_ERR(filters))
 675                                 return PTR_ERR(filters);
 676 
 677                         for (f = filters, c = count; c; f++, c--) {
 678                                 f->name &= f->name_mask;
 679                                 f->pgn &= f->pgn_mask;
 680                                 f->addr &= f->addr_mask;
 681                         }
 682                 }
 683 
 684                 lock_sock(&jsk->sk);
 685                 ofilters = jsk->filters;
 686                 jsk->filters = filters;
 687                 jsk->nfilters = count;
 688                 release_sock(&jsk->sk);
 689                 kfree(ofilters);
 690                 return 0;
 691         case SO_J1939_PROMISC:
 692                 return j1939_sk_setsockopt_flag(jsk, optval, optlen,
 693                                                 J1939_SOCK_PROMISC);
 694         case SO_J1939_ERRQUEUE:
 695                 ret = j1939_sk_setsockopt_flag(jsk, optval, optlen,
 696                                                J1939_SOCK_ERRQUEUE);
 697                 if (ret < 0)
 698                         return ret;
 699 
 700                 if (!(jsk->state & J1939_SOCK_ERRQUEUE))
 701                         skb_queue_purge(&sk->sk_error_queue);
 702                 return ret;
 703         case SO_J1939_SEND_PRIO:
 704                 if (optlen != sizeof(tmp))
 705                         return -EINVAL;
 706                 if (copy_from_user(&tmp, optval, optlen))
 707                         return -EFAULT;
 708                 if (tmp < 0 || tmp > 7)
 709                         return -EDOM;
 710                 if (tmp < 2 && !capable(CAP_NET_ADMIN))
 711                         return -EPERM;
 712                 lock_sock(&jsk->sk);
 713                 jsk->sk.sk_priority = j1939_to_sk_priority(tmp);
 714                 release_sock(&jsk->sk);
 715                 return 0;
 716         default:
 717                 return -ENOPROTOOPT;
 718         }
 719 }
 720 
 721 static int j1939_sk_getsockopt(struct socket *sock, int level, int optname,
 722                                char __user *optval, int __user *optlen)
 723 {
 724         struct sock *sk = sock->sk;
 725         struct j1939_sock *jsk = j1939_sk(sk);
 726         int ret, ulen;
 727         /* set defaults for using 'int' properties */
 728         int tmp = 0;
 729         int len = sizeof(tmp);
 730         void *val = &tmp;
 731 
 732         if (level != SOL_CAN_J1939)
 733                 return -EINVAL;
 734         if (get_user(ulen, optlen))
 735                 return -EFAULT;
 736         if (ulen < 0)
 737                 return -EINVAL;
 738 
 739         lock_sock(&jsk->sk);
 740         switch (optname) {
 741         case SO_J1939_PROMISC:
 742                 tmp = (jsk->state & J1939_SOCK_PROMISC) ? 1 : 0;
 743                 break;
 744         case SO_J1939_ERRQUEUE:
 745                 tmp = (jsk->state & J1939_SOCK_ERRQUEUE) ? 1 : 0;
 746                 break;
 747         case SO_J1939_SEND_PRIO:
 748                 tmp = j1939_prio(jsk->sk.sk_priority);
 749                 break;
 750         default:
 751                 ret = -ENOPROTOOPT;
 752                 goto no_copy;
 753         }
 754 
 755         /* copy to user, based on 'len' & 'val'
 756          * but most sockopt's are 'int' properties, and have 'len' & 'val'
 757          * left unchanged, but instead modified 'tmp'
 758          */
 759         if (len > ulen)
 760                 ret = -EFAULT;
 761         else if (put_user(len, optlen))
 762                 ret = -EFAULT;
 763         else if (copy_to_user(optval, val, len))
 764                 ret = -EFAULT;
 765         else
 766                 ret = 0;
 767  no_copy:
 768         release_sock(&jsk->sk);
 769         return ret;
 770 }
 771 
 772 static int j1939_sk_recvmsg(struct socket *sock, struct msghdr *msg,
 773                             size_t size, int flags)
 774 {
 775         struct sock *sk = sock->sk;
 776         struct sk_buff *skb;
 777         struct j1939_sk_buff_cb *skcb;
 778         int ret = 0;
 779 
 780         if (flags & ~(MSG_DONTWAIT | MSG_ERRQUEUE))
 781                 return -EINVAL;
 782 
 783         if (flags & MSG_ERRQUEUE)
 784                 return sock_recv_errqueue(sock->sk, msg, size, SOL_CAN_J1939,
 785                                           SCM_J1939_ERRQUEUE);
 786 
 787         skb = skb_recv_datagram(sk, flags, 0, &ret);
 788         if (!skb)
 789                 return ret;
 790 
 791         if (size < skb->len)
 792                 msg->msg_flags |= MSG_TRUNC;
 793         else
 794                 size = skb->len;
 795 
 796         ret = memcpy_to_msg(msg, skb->data, size);
 797         if (ret < 0) {
 798                 skb_free_datagram(sk, skb);
 799                 return ret;
 800         }
 801 
 802         skcb = j1939_skb_to_cb(skb);
 803         if (j1939_address_is_valid(skcb->addr.da))
 804                 put_cmsg(msg, SOL_CAN_J1939, SCM_J1939_DEST_ADDR,
 805                          sizeof(skcb->addr.da), &skcb->addr.da);
 806 
 807         if (skcb->addr.dst_name)
 808                 put_cmsg(msg, SOL_CAN_J1939, SCM_J1939_DEST_NAME,
 809                          sizeof(skcb->addr.dst_name), &skcb->addr.dst_name);
 810 
 811         put_cmsg(msg, SOL_CAN_J1939, SCM_J1939_PRIO,
 812                  sizeof(skcb->priority), &skcb->priority);
 813 
 814         if (msg->msg_name) {
 815                 struct sockaddr_can *paddr = msg->msg_name;
 816 
 817                 msg->msg_namelen = J1939_MIN_NAMELEN;
 818                 memset(msg->msg_name, 0, msg->msg_namelen);
 819                 paddr->can_family = AF_CAN;
 820                 paddr->can_ifindex = skb->skb_iif;
 821                 paddr->can_addr.j1939.name = skcb->addr.src_name;
 822                 paddr->can_addr.j1939.addr = skcb->addr.sa;
 823                 paddr->can_addr.j1939.pgn = skcb->addr.pgn;
 824         }
 825 
 826         sock_recv_ts_and_drops(msg, sk, skb);
 827         msg->msg_flags |= skcb->msg_flags;
 828         skb_free_datagram(sk, skb);
 829 
 830         return size;
 831 }
 832 
 833 static struct sk_buff *j1939_sk_alloc_skb(struct net_device *ndev,
 834                                           struct sock *sk,
 835                                           struct msghdr *msg, size_t size,
 836                                           int *errcode)
 837 {
 838         struct j1939_sock *jsk = j1939_sk(sk);
 839         struct j1939_sk_buff_cb *skcb;
 840         struct sk_buff *skb;
 841         int ret;
 842 
 843         skb = sock_alloc_send_skb(sk,
 844                                   size +
 845                                   sizeof(struct can_frame) -
 846                                   sizeof(((struct can_frame *)NULL)->data) +
 847                                   sizeof(struct can_skb_priv),
 848                                   msg->msg_flags & MSG_DONTWAIT, &ret);
 849         if (!skb)
 850                 goto failure;
 851 
 852         can_skb_reserve(skb);
 853         can_skb_prv(skb)->ifindex = ndev->ifindex;
 854         can_skb_prv(skb)->skbcnt = 0;
 855         skb_reserve(skb, offsetof(struct can_frame, data));
 856 
 857         ret = memcpy_from_msg(skb_put(skb, size), msg, size);
 858         if (ret < 0)
 859                 goto free_skb;
 860 
 861         skb->dev = ndev;
 862 
 863         skcb = j1939_skb_to_cb(skb);
 864         memset(skcb, 0, sizeof(*skcb));
 865         skcb->addr = jsk->addr;
 866         skcb->priority = j1939_prio(sk->sk_priority);
 867 
 868         if (msg->msg_name) {
 869                 struct sockaddr_can *addr = msg->msg_name;
 870 
 871                 if (addr->can_addr.j1939.name ||
 872                     addr->can_addr.j1939.addr != J1939_NO_ADDR) {
 873                         skcb->addr.dst_name = addr->can_addr.j1939.name;
 874                         skcb->addr.da = addr->can_addr.j1939.addr;
 875                 }
 876                 if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn))
 877                         skcb->addr.pgn = addr->can_addr.j1939.pgn;
 878         }
 879 
 880         *errcode = ret;
 881         return skb;
 882 
 883 free_skb:
 884         kfree_skb(skb);
 885 failure:
 886         *errcode = ret;
 887         return NULL;
 888 }
 889 
 890 static size_t j1939_sk_opt_stats_get_size(void)
 891 {
 892         return
 893                 nla_total_size(sizeof(u32)) + /* J1939_NLA_BYTES_ACKED */
 894                 0;
 895 }
 896 
 897 static struct sk_buff *
 898 j1939_sk_get_timestamping_opt_stats(struct j1939_session *session)
 899 {
 900         struct sk_buff *stats;
 901         u32 size;
 902 
 903         stats = alloc_skb(j1939_sk_opt_stats_get_size(), GFP_ATOMIC);
 904         if (!stats)
 905                 return NULL;
 906 
 907         if (session->skcb.addr.type == J1939_SIMPLE)
 908                 size = session->total_message_size;
 909         else
 910                 size = min(session->pkt.tx_acked * 7,
 911                            session->total_message_size);
 912 
 913         nla_put_u32(stats, J1939_NLA_BYTES_ACKED, size);
 914 
 915         return stats;
 916 }
 917 
 918 void j1939_sk_errqueue(struct j1939_session *session,
 919                        enum j1939_sk_errqueue_type type)
 920 {
 921         struct j1939_priv *priv = session->priv;
 922         struct sock *sk = session->sk;
 923         struct j1939_sock *jsk;
 924         struct sock_exterr_skb *serr;
 925         struct sk_buff *skb;
 926         char *state = "UNK";
 927         int err;
 928 
 929         /* currently we have no sk for the RX session */
 930         if (!sk)
 931                 return;
 932 
 933         jsk = j1939_sk(sk);
 934 
 935         if (!(jsk->state & J1939_SOCK_ERRQUEUE))
 936                 return;
 937 
 938         skb = j1939_sk_get_timestamping_opt_stats(session);
 939         if (!skb)
 940                 return;
 941 
 942         skb->tstamp = ktime_get_real();
 943 
 944         BUILD_BUG_ON(sizeof(struct sock_exterr_skb) > sizeof(skb->cb));
 945 
 946         serr = SKB_EXT_ERR(skb);
 947         memset(serr, 0, sizeof(*serr));
 948         switch (type) {
 949         case J1939_ERRQUEUE_ACK:
 950                 if (!(sk->sk_tsflags & SOF_TIMESTAMPING_TX_ACK)) {
 951                         kfree_skb(skb);
 952                         return;
 953                 }
 954 
 955                 serr->ee.ee_errno = ENOMSG;
 956                 serr->ee.ee_origin = SO_EE_ORIGIN_TIMESTAMPING;
 957                 serr->ee.ee_info = SCM_TSTAMP_ACK;
 958                 state = "ACK";
 959                 break;
 960         case J1939_ERRQUEUE_SCHED:
 961                 if (!(sk->sk_tsflags & SOF_TIMESTAMPING_TX_SCHED)) {
 962                         kfree_skb(skb);
 963                         return;
 964                 }
 965 
 966                 serr->ee.ee_errno = ENOMSG;
 967                 serr->ee.ee_origin = SO_EE_ORIGIN_TIMESTAMPING;
 968                 serr->ee.ee_info = SCM_TSTAMP_SCHED;
 969                 state = "SCH";
 970                 break;
 971         case J1939_ERRQUEUE_ABORT:
 972                 serr->ee.ee_errno = session->err;
 973                 serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
 974                 serr->ee.ee_info = J1939_EE_INFO_TX_ABORT;
 975                 state = "ABT";
 976                 break;
 977         default:
 978                 netdev_err(priv->ndev, "Unknown errqueue type %i\n", type);
 979         }
 980 
 981         serr->opt_stats = true;
 982         if (sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)
 983                 serr->ee.ee_data = session->tskey;
 984 
 985         netdev_dbg(session->priv->ndev, "%s: 0x%p tskey: %i, state: %s\n",
 986                    __func__, session, session->tskey, state);
 987         err = sock_queue_err_skb(sk, skb);
 988 
 989         if (err)
 990                 kfree_skb(skb);
 991 };
 992 
 993 void j1939_sk_send_loop_abort(struct sock *sk, int err)
 994 {
 995         sk->sk_err = err;
 996 
 997         sk->sk_error_report(sk);
 998 }
 999 
1000 static int j1939_sk_send_loop(struct j1939_priv *priv,  struct sock *sk,
1001                               struct msghdr *msg, size_t size)
1002 
1003 {
1004         struct j1939_sock *jsk = j1939_sk(sk);
1005         struct j1939_session *session = j1939_sk_get_incomplete_session(jsk);
1006         struct sk_buff *skb;
1007         size_t segment_size, todo_size;
1008         int ret = 0;
1009 
1010         if (session &&
1011             session->total_message_size != session->total_queued_size + size) {
1012                 j1939_session_put(session);
1013                 return -EIO;
1014         }
1015 
1016         todo_size = size;
1017 
1018         while (todo_size) {
1019                 struct j1939_sk_buff_cb *skcb;
1020 
1021                 segment_size = min_t(size_t, J1939_MAX_TP_PACKET_SIZE,
1022                                      todo_size);
1023 
1024                 /* Allocate skb for one segment */
1025                 skb = j1939_sk_alloc_skb(priv->ndev, sk, msg, segment_size,
1026                                          &ret);
1027                 if (ret)
1028                         break;
1029 
1030                 skcb = j1939_skb_to_cb(skb);
1031 
1032                 if (!session) {
1033                         /* at this point the size should be full size
1034                          * of the session
1035                          */
1036                         skcb->offset = 0;
1037                         session = j1939_tp_send(priv, skb, size);
1038                         if (IS_ERR(session)) {
1039                                 ret = PTR_ERR(session);
1040                                 goto kfree_skb;
1041                         }
1042                         if (j1939_sk_queue_session(session)) {
1043                                 /* try to activate session if we a
1044                                  * fist in the queue
1045                                  */
1046                                 if (!j1939_session_activate(session)) {
1047                                         j1939_tp_schedule_txtimer(session, 0);
1048                                 } else {
1049                                         ret = -EBUSY;
1050                                         session->err = ret;
1051                                         j1939_sk_queue_drop_all(priv, jsk,
1052                                                                 EBUSY);
1053                                         break;
1054                                 }
1055                         }
1056                 } else {
1057                         skcb->offset = session->total_queued_size;
1058                         j1939_session_skb_queue(session, skb);
1059                 }
1060 
1061                 todo_size -= segment_size;
1062                 session->total_queued_size += segment_size;
1063         }
1064 
1065         switch (ret) {
1066         case 0: /* OK */
1067                 if (todo_size)
1068                         netdev_warn(priv->ndev,
1069                                     "no error found and not completely queued?! %zu\n",
1070                                     todo_size);
1071                 ret = size;
1072                 break;
1073         case -ERESTARTSYS:
1074                 ret = -EINTR;
1075                 /* fall through */
1076         case -EAGAIN: /* OK */
1077                 if (todo_size != size)
1078                         ret = size - todo_size;
1079                 break;
1080         default: /* ERROR */
1081                 break;
1082         }
1083 
1084         if (session)
1085                 j1939_session_put(session);
1086 
1087         return ret;
1088 
1089  kfree_skb:
1090         kfree_skb(skb);
1091         return ret;
1092 }
1093 
1094 static int j1939_sk_sendmsg(struct socket *sock, struct msghdr *msg,
1095                             size_t size)
1096 {
1097         struct sock *sk = sock->sk;
1098         struct j1939_sock *jsk = j1939_sk(sk);
1099         struct j1939_priv *priv;
1100         int ifindex;
1101         int ret;
1102 
1103         lock_sock(sock->sk);
1104         /* various socket state tests */
1105         if (!(jsk->state & J1939_SOCK_BOUND)) {
1106                 ret = -EBADFD;
1107                 goto sendmsg_done;
1108         }
1109 
1110         priv = jsk->priv;
1111         ifindex = jsk->ifindex;
1112 
1113         if (!jsk->addr.src_name && jsk->addr.sa == J1939_NO_ADDR) {
1114                 /* no source address assigned yet */
1115                 ret = -EBADFD;
1116                 goto sendmsg_done;
1117         }
1118 
1119         /* deal with provided destination address info */
1120         if (msg->msg_name) {
1121                 struct sockaddr_can *addr = msg->msg_name;
1122 
1123                 if (msg->msg_namelen < J1939_MIN_NAMELEN) {
1124                         ret = -EINVAL;
1125                         goto sendmsg_done;
1126                 }
1127 
1128                 if (addr->can_family != AF_CAN) {
1129                         ret = -EINVAL;
1130                         goto sendmsg_done;
1131                 }
1132 
1133                 if (addr->can_ifindex && addr->can_ifindex != ifindex) {
1134                         ret = -EBADFD;
1135                         goto sendmsg_done;
1136                 }
1137 
1138                 if (j1939_pgn_is_valid(addr->can_addr.j1939.pgn) &&
1139                     !j1939_pgn_is_clean_pdu(addr->can_addr.j1939.pgn)) {
1140                         ret = -EINVAL;
1141                         goto sendmsg_done;
1142                 }
1143 
1144                 if (!addr->can_addr.j1939.name &&
1145                     addr->can_addr.j1939.addr == J1939_NO_ADDR &&
1146                     !sock_flag(sk, SOCK_BROADCAST)) {
1147                         /* broadcast, but SO_BROADCAST not set */
1148                         ret = -EACCES;
1149                         goto sendmsg_done;
1150                 }
1151         } else {
1152                 if (!jsk->addr.dst_name && jsk->addr.da == J1939_NO_ADDR &&
1153                     !sock_flag(sk, SOCK_BROADCAST)) {
1154                         /* broadcast, but SO_BROADCAST not set */
1155                         ret = -EACCES;
1156                         goto sendmsg_done;
1157                 }
1158         }
1159 
1160         ret = j1939_sk_send_loop(priv, sk, msg, size);
1161 
1162 sendmsg_done:
1163         release_sock(sock->sk);
1164 
1165         return ret;
1166 }
1167 
1168 void j1939_sk_netdev_event_netdown(struct j1939_priv *priv)
1169 {
1170         struct j1939_sock *jsk;
1171         int error_code = ENETDOWN;
1172 
1173         spin_lock_bh(&priv->j1939_socks_lock);
1174         list_for_each_entry(jsk, &priv->j1939_socks, list) {
1175                 jsk->sk.sk_err = error_code;
1176                 if (!sock_flag(&jsk->sk, SOCK_DEAD))
1177                         jsk->sk.sk_error_report(&jsk->sk);
1178 
1179                 j1939_sk_queue_drop_all(priv, jsk, error_code);
1180         }
1181         spin_unlock_bh(&priv->j1939_socks_lock);
1182 }
1183 
1184 static int j1939_sk_no_ioctlcmd(struct socket *sock, unsigned int cmd,
1185                                 unsigned long arg)
1186 {
1187         /* no ioctls for socket layer -> hand it down to NIC layer */
1188         return -ENOIOCTLCMD;
1189 }
1190 
1191 static const struct proto_ops j1939_ops = {
1192         .family = PF_CAN,
1193         .release = j1939_sk_release,
1194         .bind = j1939_sk_bind,
1195         .connect = j1939_sk_connect,
1196         .socketpair = sock_no_socketpair,
1197         .accept = sock_no_accept,
1198         .getname = j1939_sk_getname,
1199         .poll = datagram_poll,
1200         .ioctl = j1939_sk_no_ioctlcmd,
1201         .listen = sock_no_listen,
1202         .shutdown = sock_no_shutdown,
1203         .setsockopt = j1939_sk_setsockopt,
1204         .getsockopt = j1939_sk_getsockopt,
1205         .sendmsg = j1939_sk_sendmsg,
1206         .recvmsg = j1939_sk_recvmsg,
1207         .mmap = sock_no_mmap,
1208         .sendpage = sock_no_sendpage,
1209 };
1210 
1211 static struct proto j1939_proto __read_mostly = {
1212         .name = "CAN_J1939",
1213         .owner = THIS_MODULE,
1214         .obj_size = sizeof(struct j1939_sock),
1215         .init = j1939_sk_init,
1216 };
1217 
1218 const struct can_proto j1939_can_proto = {
1219         .type = SOCK_DGRAM,
1220         .protocol = CAN_J1939,
1221         .ops = &j1939_ops,
1222         .prot = &j1939_proto,
1223 };
/* [<][>][^][v][top][bottom][index][help] */
root/net/can/j1939/socket.c

DEFINITIONS
