1 // SPDX-License-Identifier: GPL-2.0 2 // Copyright (c) 2010-2011 EIA Electronics, 3 // Kurt Van Dijck <kurt.van.dijck@eia.be> 4 // Copyright (c) 2018 Protonic, 5 // Robin van der Gracht <robin@protonic.nl> 6 // Copyright (c) 2017-2019 Pengutronix, 7 // Marc Kleine-Budde <kernel@pengutronix.de> 8 // Copyright (c) 2017-2019 Pengutronix, 9 // Oleksij Rempel <kernel@pengutronix.de> 10 11 #include <linux/can/skb.h> 12 13 #include "j1939-priv.h" 14 15 #define J1939_XTP_TX_RETRY_LIMIT 100 16 17 #define J1939_ETP_PGN_CTL 0xc800 18 #define J1939_ETP_PGN_DAT 0xc700 19 #define J1939_TP_PGN_CTL 0xec00 20 #define J1939_TP_PGN_DAT 0xeb00 21 22 #define J1939_TP_CMD_RTS 0x10 23 #define J1939_TP_CMD_CTS 0x11 24 #define J1939_TP_CMD_EOMA 0x13 25 #define J1939_TP_CMD_BAM 0x20 26 #define J1939_TP_CMD_ABORT 0xff 27 28 #define J1939_ETP_CMD_RTS 0x14 29 #define J1939_ETP_CMD_CTS 0x15 30 #define J1939_ETP_CMD_DPO 0x16 31 #define J1939_ETP_CMD_EOMA 0x17 32 #define J1939_ETP_CMD_ABORT 0xff 33 34 enum j1939_xtp_abort { 35 J1939_XTP_NO_ABORT = 0, 36 J1939_XTP_ABORT_BUSY = 1, 37 /* Already in one or more connection managed sessions and 38 * cannot support another. 39 * 40 * EALREADY: 41 * Operation already in progress 42 */ 43 44 J1939_XTP_ABORT_RESOURCE = 2, 45 /* System resources were needed for another task so this 46 * connection managed session was terminated. 47 * 48 * EMSGSIZE: 49 * The socket type requires that message be sent atomically, 50 * and the size of the message to be sent made this 51 * impossible. 52 */ 53 54 J1939_XTP_ABORT_TIMEOUT = 3, 55 /* A timeout occurred and this is the connection abort to 56 * close the session. 57 * 58 * EHOSTUNREACH: 59 * The destination host cannot be reached (probably because 60 * the host is down or a remote router cannot reach it). 61 */ 62 63 J1939_XTP_ABORT_GENERIC = 4, 64 /* CTS messages received when data transfer is in progress 65 * 66 * EBADMSG: 67 * Not a data message 68 */ 69 70 J1939_XTP_ABORT_FAULT = 5, 71 /* Maximal retransmit request limit reached 72 * 73 * ENOTRECOVERABLE: 74 * State not recoverable 75 */ 76 77 J1939_XTP_ABORT_UNEXPECTED_DATA = 6, 78 /* Unexpected data transfer packet 79 * 80 * ENOTCONN: 81 * Transport endpoint is not connected 82 */ 83 84 J1939_XTP_ABORT_BAD_SEQ = 7, 85 /* Bad sequence number (and software is not able to recover) 86 * 87 * EILSEQ: 88 * Illegal byte sequence 89 */ 90 91 J1939_XTP_ABORT_DUP_SEQ = 8, 92 /* Duplicate sequence number (and software is not able to 93 * recover) 94 */ 95 96 J1939_XTP_ABORT_EDPO_UNEXPECTED = 9, 97 /* Unexpected EDPO packet (ETP) or Message size > 1785 bytes 98 * (TP) 99 */ 100 101 J1939_XTP_ABORT_BAD_EDPO_PGN = 10, 102 /* Unexpected EDPO PGN (PGN in EDPO is bad) */ 103 104 J1939_XTP_ABORT_EDPO_OUTOF_CTS = 11, 105 /* EDPO number of packets is greater than CTS */ 106 107 J1939_XTP_ABORT_BAD_EDPO_OFFSET = 12, 108 /* Bad EDPO offset */ 109 110 J1939_XTP_ABORT_OTHER_DEPRECATED = 13, 111 /* Deprecated. Use 250 instead (Any other reason) */ 112 113 J1939_XTP_ABORT_ECTS_UNXPECTED_PGN = 14, 114 /* Unexpected ECTS PGN (PGN in ECTS is bad) */ 115 116 J1939_XTP_ABORT_ECTS_TOO_BIG = 15, 117 /* ECTS requested packets exceeds message size */ 118 119 J1939_XTP_ABORT_OTHER = 250, 120 /* Any other reason (if a Connection Abort reason is 121 * identified that is not listed in the table use code 250) 122 */ 123 }; 124 125 static unsigned int j1939_tp_block = 255; 126 static unsigned int j1939_tp_packet_delay; 127 static unsigned int j1939_tp_padding = 1; 128 129 /* helpers */ 130 static const char *j1939_xtp_abort_to_str(enum j1939_xtp_abort abort) 131 { 132 switch (abort) { 133 case J1939_XTP_ABORT_BUSY: 134 return "Already in one or more connection managed sessions and cannot support another."; 135 case J1939_XTP_ABORT_RESOURCE: 136 return "System resources were needed for another task so this connection managed session was terminated."; 137 case J1939_XTP_ABORT_TIMEOUT: 138 return "A timeout occurred and this is the connection abort to close the session."; 139 case J1939_XTP_ABORT_GENERIC: 140 return "CTS messages received when data transfer is in progress"; 141 case J1939_XTP_ABORT_FAULT: 142 return "Maximal retransmit request limit reached"; 143 case J1939_XTP_ABORT_UNEXPECTED_DATA: 144 return "Unexpected data transfer packet"; 145 case J1939_XTP_ABORT_BAD_SEQ: 146 return "Bad sequence number (and software is not able to recover)"; 147 case J1939_XTP_ABORT_DUP_SEQ: 148 return "Duplicate sequence number (and software is not able to recover)"; 149 case J1939_XTP_ABORT_EDPO_UNEXPECTED: 150 return "Unexpected EDPO packet (ETP) or Message size > 1785 bytes (TP)"; 151 case J1939_XTP_ABORT_BAD_EDPO_PGN: 152 return "Unexpected EDPO PGN (PGN in EDPO is bad)"; 153 case J1939_XTP_ABORT_EDPO_OUTOF_CTS: 154 return "EDPO number of packets is greater than CTS"; 155 case J1939_XTP_ABORT_BAD_EDPO_OFFSET: 156 return "Bad EDPO offset"; 157 case J1939_XTP_ABORT_OTHER_DEPRECATED: 158 return "Deprecated. Use 250 instead (Any other reason)"; 159 case J1939_XTP_ABORT_ECTS_UNXPECTED_PGN: 160 return "Unexpected ECTS PGN (PGN in ECTS is bad)"; 161 case J1939_XTP_ABORT_ECTS_TOO_BIG: 162 return "ECTS requested packets exceeds message size"; 163 case J1939_XTP_ABORT_OTHER: 164 return "Any other reason (if a Connection Abort reason is identified that is not listed in the table use code 250)"; 165 default: 166 return "<unknown>"; 167 } 168 } 169 170 static int j1939_xtp_abort_to_errno(struct j1939_priv *priv, 171 enum j1939_xtp_abort abort) 172 { 173 int err; 174 175 switch (abort) { 176 case J1939_XTP_NO_ABORT: 177 WARN_ON_ONCE(abort == J1939_XTP_NO_ABORT); 178 err = 0; 179 break; 180 case J1939_XTP_ABORT_BUSY: 181 err = EALREADY; 182 break; 183 case J1939_XTP_ABORT_RESOURCE: 184 err = EMSGSIZE; 185 break; 186 case J1939_XTP_ABORT_TIMEOUT: 187 err = EHOSTUNREACH; 188 break; 189 case J1939_XTP_ABORT_GENERIC: 190 err = EBADMSG; 191 break; 192 case J1939_XTP_ABORT_FAULT: 193 err = ENOTRECOVERABLE; 194 break; 195 case J1939_XTP_ABORT_UNEXPECTED_DATA: 196 err = ENOTCONN; 197 break; 198 case J1939_XTP_ABORT_BAD_SEQ: 199 err = EILSEQ; 200 break; 201 case J1939_XTP_ABORT_DUP_SEQ: 202 err = EPROTO; 203 break; 204 case J1939_XTP_ABORT_EDPO_UNEXPECTED: 205 err = EPROTO; 206 break; 207 case J1939_XTP_ABORT_BAD_EDPO_PGN: 208 err = EPROTO; 209 break; 210 case J1939_XTP_ABORT_EDPO_OUTOF_CTS: 211 err = EPROTO; 212 break; 213 case J1939_XTP_ABORT_BAD_EDPO_OFFSET: 214 err = EPROTO; 215 break; 216 case J1939_XTP_ABORT_OTHER_DEPRECATED: 217 err = EPROTO; 218 break; 219 case J1939_XTP_ABORT_ECTS_UNXPECTED_PGN: 220 err = EPROTO; 221 break; 222 case J1939_XTP_ABORT_ECTS_TOO_BIG: 223 err = EPROTO; 224 break; 225 case J1939_XTP_ABORT_OTHER: 226 err = EPROTO; 227 break; 228 default: 229 netdev_warn(priv->ndev, "Unknown abort code %i", abort); 230 err = EPROTO; 231 } 232 233 return err; 234 } 235 236 static inline void j1939_session_list_lock(struct j1939_priv *priv) 237 { 238 spin_lock_bh(&priv->active_session_list_lock); 239 } 240 241 static inline void j1939_session_list_unlock(struct j1939_priv *priv) 242 { 243 spin_unlock_bh(&priv->active_session_list_lock); 244 } 245 246 void j1939_session_get(struct j1939_session *session) 247 { 248 kref_get(&session->kref); 249 } 250 251 /* session completion functions */ 252 static void __j1939_session_drop(struct j1939_session *session) 253 { 254 if (!session->transmission) 255 return; 256 257 j1939_sock_pending_del(session->sk); 258 sock_put(session->sk); 259 } 260 261 static void j1939_session_destroy(struct j1939_session *session) 262 { 263 struct sk_buff *skb; 264 265 if (session->transmission) { 266 if (session->err) 267 j1939_sk_errqueue(session, J1939_ERRQUEUE_TX_ABORT); 268 else 269 j1939_sk_errqueue(session, J1939_ERRQUEUE_TX_ACK); 270 } else if (session->err) { 271 j1939_sk_errqueue(session, J1939_ERRQUEUE_RX_ABORT); 272 } 273 274 netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); 275 276 WARN_ON_ONCE(!list_empty(&session->sk_session_queue_entry)); 277 WARN_ON_ONCE(!list_empty(&session->active_session_list_entry)); 278 279 while ((skb = skb_dequeue(&session->skb_queue)) != NULL) { 280 /* drop ref taken in j1939_session_skb_queue() */ 281 skb_unref(skb); 282 kfree_skb(skb); 283 } 284 __j1939_session_drop(session); 285 j1939_priv_put(session->priv); 286 kfree(session); 287 } 288 289 static void __j1939_session_release(struct kref *kref) 290 { 291 struct j1939_session *session = container_of(kref, struct j1939_session, 292 kref); 293 294 j1939_session_destroy(session); 295 } 296 297 void j1939_session_put(struct j1939_session *session) 298 { 299 kref_put(&session->kref, __j1939_session_release); 300 } 301 302 static void j1939_session_txtimer_cancel(struct j1939_session *session) 303 { 304 if (hrtimer_cancel(&session->txtimer)) 305 j1939_session_put(session); 306 } 307 308 static void j1939_session_rxtimer_cancel(struct j1939_session *session) 309 { 310 if (hrtimer_cancel(&session->rxtimer)) 311 j1939_session_put(session); 312 } 313 314 void j1939_session_timers_cancel(struct j1939_session *session) 315 { 316 j1939_session_txtimer_cancel(session); 317 j1939_session_rxtimer_cancel(session); 318 } 319 320 static inline bool j1939_cb_is_broadcast(const struct j1939_sk_buff_cb *skcb) 321 { 322 return (!skcb->addr.dst_name && (skcb->addr.da == 0xff)); 323 } 324 325 static void j1939_session_skb_drop_old(struct j1939_session *session) 326 { 327 struct sk_buff *do_skb; 328 struct j1939_sk_buff_cb *do_skcb; 329 unsigned int offset_start; 330 unsigned long flags; 331 332 if (skb_queue_len(&session->skb_queue) < 2) 333 return; 334 335 offset_start = session->pkt.tx_acked * 7; 336 337 spin_lock_irqsave(&session->skb_queue.lock, flags); 338 do_skb = skb_peek(&session->skb_queue); 339 do_skcb = j1939_skb_to_cb(do_skb); 340 341 if ((do_skcb->offset + do_skb->len) < offset_start) { 342 __skb_unlink(do_skb, &session->skb_queue); 343 /* drop ref taken in j1939_session_skb_queue() */ 344 skb_unref(do_skb); 345 spin_unlock_irqrestore(&session->skb_queue.lock, flags); 346 347 kfree_skb(do_skb); 348 } else { 349 spin_unlock_irqrestore(&session->skb_queue.lock, flags); 350 } 351 } 352 353 void j1939_session_skb_queue(struct j1939_session *session, 354 struct sk_buff *skb) 355 { 356 struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); 357 struct j1939_priv *priv = session->priv; 358 359 j1939_ac_fixup(priv, skb); 360 361 if (j1939_address_is_unicast(skcb->addr.da) && 362 priv->ents[skcb->addr.da].nusers) 363 skcb->flags |= J1939_ECU_LOCAL_DST; 364 365 skcb->flags |= J1939_ECU_LOCAL_SRC; 366 367 skb_get(skb); 368 skb_queue_tail(&session->skb_queue, skb); 369 } 370 371 static struct 372 sk_buff *j1939_session_skb_get_by_offset(struct j1939_session *session, 373 unsigned int offset_start) 374 { 375 struct j1939_priv *priv = session->priv; 376 struct j1939_sk_buff_cb *do_skcb; 377 struct sk_buff *skb = NULL; 378 struct sk_buff *do_skb; 379 unsigned long flags; 380 381 spin_lock_irqsave(&session->skb_queue.lock, flags); 382 skb_queue_walk(&session->skb_queue, do_skb) { 383 do_skcb = j1939_skb_to_cb(do_skb); 384 385 if ((offset_start >= do_skcb->offset && 386 offset_start < (do_skcb->offset + do_skb->len)) || 387 (offset_start == 0 && do_skcb->offset == 0 && do_skb->len == 0)) { 388 skb = do_skb; 389 } 390 } 391 392 if (skb) 393 skb_get(skb); 394 395 spin_unlock_irqrestore(&session->skb_queue.lock, flags); 396 397 if (!skb) 398 netdev_dbg(priv->ndev, "%s: 0x%p: no skb found for start: %i, queue size: %i\n", 399 __func__, session, offset_start, 400 skb_queue_len(&session->skb_queue)); 401 402 return skb; 403 } 404 405 static struct sk_buff *j1939_session_skb_get(struct j1939_session *session) 406 { 407 unsigned int offset_start; 408 409 offset_start = session->pkt.dpo * 7; 410 return j1939_session_skb_get_by_offset(session, offset_start); 411 } 412 413 /* see if we are receiver 414 * returns 0 for broadcasts, although we will receive them 415 */ 416 static inline int j1939_tp_im_receiver(const struct j1939_sk_buff_cb *skcb) 417 { 418 return skcb->flags & J1939_ECU_LOCAL_DST; 419 } 420 421 /* see if we are sender */ 422 static inline int j1939_tp_im_transmitter(const struct j1939_sk_buff_cb *skcb) 423 { 424 return skcb->flags & J1939_ECU_LOCAL_SRC; 425 } 426 427 /* see if we are involved as either receiver or transmitter */ 428 static int j1939_tp_im_involved(const struct j1939_sk_buff_cb *skcb, bool swap) 429 { 430 if (swap) 431 return j1939_tp_im_receiver(skcb); 432 else 433 return j1939_tp_im_transmitter(skcb); 434 } 435 436 static int j1939_tp_im_involved_anydir(struct j1939_sk_buff_cb *skcb) 437 { 438 return skcb->flags & (J1939_ECU_LOCAL_SRC | J1939_ECU_LOCAL_DST); 439 } 440 441 /* extract pgn from flow-ctl message */ 442 static inline pgn_t j1939_xtp_ctl_to_pgn(const u8 *dat) 443 { 444 pgn_t pgn; 445 446 pgn = (dat[7] << 16) | (dat[6] << 8) | (dat[5] << 0); 447 if (j1939_pgn_is_pdu1(pgn)) 448 pgn &= 0xffff00; 449 return pgn; 450 } 451 452 static inline unsigned int j1939_tp_ctl_to_size(const u8 *dat) 453 { 454 return (dat[2] << 8) + (dat[1] << 0); 455 } 456 457 static inline unsigned int j1939_etp_ctl_to_packet(const u8 *dat) 458 { 459 return (dat[4] << 16) | (dat[3] << 8) | (dat[2] << 0); 460 } 461 462 static inline unsigned int j1939_etp_ctl_to_size(const u8 *dat) 463 { 464 return (dat[4] << 24) | (dat[3] << 16) | 465 (dat[2] << 8) | (dat[1] << 0); 466 } 467 468 /* find existing session: 469 * reverse: swap cb's src & dst 470 * there is no problem with matching broadcasts, since 471 * broadcasts (no dst, no da) would never call this 472 * with reverse == true 473 */ 474 static bool j1939_session_match(struct j1939_addr *se_addr, 475 struct j1939_addr *sk_addr, bool reverse) 476 { 477 if (se_addr->type != sk_addr->type) 478 return false; 479 480 if (reverse) { 481 if (se_addr->src_name) { 482 if (se_addr->src_name != sk_addr->dst_name) 483 return false; 484 } else if (se_addr->sa != sk_addr->da) { 485 return false; 486 } 487 488 if (se_addr->dst_name) { 489 if (se_addr->dst_name != sk_addr->src_name) 490 return false; 491 } else if (se_addr->da != sk_addr->sa) { 492 return false; 493 } 494 } else { 495 if (se_addr->src_name) { 496 if (se_addr->src_name != sk_addr->src_name) 497 return false; 498 } else if (se_addr->sa != sk_addr->sa) { 499 return false; 500 } 501 502 if (se_addr->dst_name) { 503 if (se_addr->dst_name != sk_addr->dst_name) 504 return false; 505 } else if (se_addr->da != sk_addr->da) { 506 return false; 507 } 508 } 509 510 return true; 511 } 512 513 static struct 514 j1939_session *j1939_session_get_by_addr_locked(struct j1939_priv *priv, 515 struct list_head *root, 516 struct j1939_addr *addr, 517 bool reverse, bool transmitter) 518 { 519 struct j1939_session *session; 520 521 lockdep_assert_held(&priv->active_session_list_lock); 522 523 list_for_each_entry(session, root, active_session_list_entry) { 524 j1939_session_get(session); 525 if (j1939_session_match(&session->skcb.addr, addr, reverse) && 526 session->transmission == transmitter) 527 return session; 528 j1939_session_put(session); 529 } 530 531 return NULL; 532 } 533 534 static struct 535 j1939_session *j1939_session_get_simple(struct j1939_priv *priv, 536 struct sk_buff *skb) 537 { 538 struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); 539 struct j1939_session *session; 540 541 lockdep_assert_held(&priv->active_session_list_lock); 542 543 list_for_each_entry(session, &priv->active_session_list, 544 active_session_list_entry) { 545 j1939_session_get(session); 546 if (session->skcb.addr.type == J1939_SIMPLE && 547 session->tskey == skcb->tskey && session->sk == skb->sk) 548 return session; 549 j1939_session_put(session); 550 } 551 552 return NULL; 553 } 554 555 static struct 556 j1939_session *j1939_session_get_by_addr(struct j1939_priv *priv, 557 struct j1939_addr *addr, 558 bool reverse, bool transmitter) 559 { 560 struct j1939_session *session; 561 562 j1939_session_list_lock(priv); 563 session = j1939_session_get_by_addr_locked(priv, 564 &priv->active_session_list, 565 addr, reverse, transmitter); 566 j1939_session_list_unlock(priv); 567 568 return session; 569 } 570 571 static void j1939_skbcb_swap(struct j1939_sk_buff_cb *skcb) 572 { 573 u8 tmp = 0; 574 575 swap(skcb->addr.dst_name, skcb->addr.src_name); 576 swap(skcb->addr.da, skcb->addr.sa); 577 578 /* swap SRC and DST flags, leave other untouched */ 579 if (skcb->flags & J1939_ECU_LOCAL_SRC) 580 tmp |= J1939_ECU_LOCAL_DST; 581 if (skcb->flags & J1939_ECU_LOCAL_DST) 582 tmp |= J1939_ECU_LOCAL_SRC; 583 skcb->flags &= ~(J1939_ECU_LOCAL_SRC | J1939_ECU_LOCAL_DST); 584 skcb->flags |= tmp; 585 } 586 587 static struct 588 sk_buff *j1939_tp_tx_dat_new(struct j1939_priv *priv, 589 const struct j1939_sk_buff_cb *re_skcb, 590 bool ctl, 591 bool swap_src_dst) 592 { 593 struct sk_buff *skb; 594 struct j1939_sk_buff_cb *skcb; 595 596 skb = alloc_skb(sizeof(struct can_frame) + sizeof(struct can_skb_priv), 597 GFP_ATOMIC); 598 if (unlikely(!skb)) 599 return ERR_PTR(-ENOMEM); 600 601 skb->dev = priv->ndev; 602 can_skb_reserve(skb); 603 can_skb_prv(skb)->ifindex = priv->ndev->ifindex; 604 can_skb_prv(skb)->skbcnt = 0; 605 /* reserve CAN header */ 606 skb_reserve(skb, offsetof(struct can_frame, data)); 607 608 /* skb->cb must be large enough to hold a j1939_sk_buff_cb structure */ 609 BUILD_BUG_ON(sizeof(skb->cb) < sizeof(*re_skcb)); 610 611 memcpy(skb->cb, re_skcb, sizeof(*re_skcb)); 612 skcb = j1939_skb_to_cb(skb); 613 if (swap_src_dst) 614 j1939_skbcb_swap(skcb); 615 616 if (ctl) { 617 if (skcb->addr.type == J1939_ETP) 618 skcb->addr.pgn = J1939_ETP_PGN_CTL; 619 else 620 skcb->addr.pgn = J1939_TP_PGN_CTL; 621 } else { 622 if (skcb->addr.type == J1939_ETP) 623 skcb->addr.pgn = J1939_ETP_PGN_DAT; 624 else 625 skcb->addr.pgn = J1939_TP_PGN_DAT; 626 } 627 628 return skb; 629 } 630 631 /* TP transmit packet functions */ 632 static int j1939_tp_tx_dat(struct j1939_session *session, 633 const u8 *dat, int len) 634 { 635 struct j1939_priv *priv = session->priv; 636 struct sk_buff *skb; 637 638 skb = j1939_tp_tx_dat_new(priv, &session->skcb, 639 false, false); 640 if (IS_ERR(skb)) 641 return PTR_ERR(skb); 642 643 skb_put_data(skb, dat, len); 644 if (j1939_tp_padding && len < 8) 645 memset(skb_put(skb, 8 - len), 0xff, 8 - len); 646 647 return j1939_send_one(priv, skb); 648 } 649 650 static int j1939_xtp_do_tx_ctl(struct j1939_priv *priv, 651 const struct j1939_sk_buff_cb *re_skcb, 652 bool swap_src_dst, pgn_t pgn, const u8 *dat) 653 { 654 struct sk_buff *skb; 655 u8 *skdat; 656 657 if (!j1939_tp_im_involved(re_skcb, swap_src_dst)) 658 return 0; 659 660 skb = j1939_tp_tx_dat_new(priv, re_skcb, true, swap_src_dst); 661 if (IS_ERR(skb)) 662 return PTR_ERR(skb); 663 664 skdat = skb_put(skb, 8); 665 memcpy(skdat, dat, 5); 666 skdat[5] = (pgn >> 0); 667 skdat[6] = (pgn >> 8); 668 skdat[7] = (pgn >> 16); 669 670 return j1939_send_one(priv, skb); 671 } 672 673 static inline int j1939_tp_tx_ctl(struct j1939_session *session, 674 bool swap_src_dst, const u8 *dat) 675 { 676 struct j1939_priv *priv = session->priv; 677 678 return j1939_xtp_do_tx_ctl(priv, &session->skcb, 679 swap_src_dst, 680 session->skcb.addr.pgn, dat); 681 } 682 683 static int j1939_xtp_tx_abort(struct j1939_priv *priv, 684 const struct j1939_sk_buff_cb *re_skcb, 685 bool swap_src_dst, 686 enum j1939_xtp_abort err, 687 pgn_t pgn) 688 { 689 u8 dat[5]; 690 691 if (!j1939_tp_im_involved(re_skcb, swap_src_dst)) 692 return 0; 693 694 memset(dat, 0xff, sizeof(dat)); 695 dat[0] = J1939_TP_CMD_ABORT; 696 dat[1] = err; 697 return j1939_xtp_do_tx_ctl(priv, re_skcb, swap_src_dst, pgn, dat); 698 } 699 700 void j1939_tp_schedule_txtimer(struct j1939_session *session, int msec) 701 { 702 j1939_session_get(session); 703 hrtimer_start(&session->txtimer, ms_to_ktime(msec), 704 HRTIMER_MODE_REL_SOFT); 705 } 706 707 static inline void j1939_tp_set_rxtimeout(struct j1939_session *session, 708 int msec) 709 { 710 j1939_session_rxtimer_cancel(session); 711 j1939_session_get(session); 712 hrtimer_start(&session->rxtimer, ms_to_ktime(msec), 713 HRTIMER_MODE_REL_SOFT); 714 } 715 716 static int j1939_session_tx_rts(struct j1939_session *session) 717 { 718 u8 dat[8]; 719 int ret; 720 721 memset(dat, 0xff, sizeof(dat)); 722 723 dat[1] = (session->total_message_size >> 0); 724 dat[2] = (session->total_message_size >> 8); 725 dat[3] = session->pkt.total; 726 727 if (session->skcb.addr.type == J1939_ETP) { 728 dat[0] = J1939_ETP_CMD_RTS; 729 dat[1] = (session->total_message_size >> 0); 730 dat[2] = (session->total_message_size >> 8); 731 dat[3] = (session->total_message_size >> 16); 732 dat[4] = (session->total_message_size >> 24); 733 } else if (j1939_cb_is_broadcast(&session->skcb)) { 734 dat[0] = J1939_TP_CMD_BAM; 735 /* fake cts for broadcast */ 736 session->pkt.tx = 0; 737 } else { 738 dat[0] = J1939_TP_CMD_RTS; 739 dat[4] = dat[3]; 740 } 741 742 if (dat[0] == session->last_txcmd) 743 /* done already */ 744 return 0; 745 746 ret = j1939_tp_tx_ctl(session, false, dat); 747 if (ret < 0) 748 return ret; 749 750 session->last_txcmd = dat[0]; 751 if (dat[0] == J1939_TP_CMD_BAM) { 752 j1939_tp_schedule_txtimer(session, 50); 753 j1939_tp_set_rxtimeout(session, 250); 754 } else { 755 j1939_tp_set_rxtimeout(session, 1250); 756 } 757 758 netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); 759 760 return 0; 761 } 762 763 static int j1939_session_tx_dpo(struct j1939_session *session) 764 { 765 unsigned int pkt; 766 u8 dat[8]; 767 int ret; 768 769 memset(dat, 0xff, sizeof(dat)); 770 771 dat[0] = J1939_ETP_CMD_DPO; 772 session->pkt.dpo = session->pkt.tx_acked; 773 pkt = session->pkt.dpo; 774 dat[1] = session->pkt.last - session->pkt.tx_acked; 775 dat[2] = (pkt >> 0); 776 dat[3] = (pkt >> 8); 777 dat[4] = (pkt >> 16); 778 779 ret = j1939_tp_tx_ctl(session, false, dat); 780 if (ret < 0) 781 return ret; 782 783 session->last_txcmd = dat[0]; 784 j1939_tp_set_rxtimeout(session, 1250); 785 session->pkt.tx = session->pkt.tx_acked; 786 787 netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); 788 789 return 0; 790 } 791 792 static int j1939_session_tx_dat(struct j1939_session *session) 793 { 794 struct j1939_priv *priv = session->priv; 795 struct j1939_sk_buff_cb *se_skcb; 796 int offset, pkt_done, pkt_end; 797 unsigned int len, pdelay; 798 struct sk_buff *se_skb; 799 const u8 *tpdat; 800 int ret = 0; 801 u8 dat[8]; 802 803 se_skb = j1939_session_skb_get_by_offset(session, session->pkt.tx * 7); 804 if (!se_skb) 805 return -ENOBUFS; 806 807 se_skcb = j1939_skb_to_cb(se_skb); 808 tpdat = se_skb->data; 809 ret = 0; 810 pkt_done = 0; 811 if (session->skcb.addr.type != J1939_ETP && 812 j1939_cb_is_broadcast(&session->skcb)) 813 pkt_end = session->pkt.total; 814 else 815 pkt_end = session->pkt.last; 816 817 while (session->pkt.tx < pkt_end) { 818 dat[0] = session->pkt.tx - session->pkt.dpo + 1; 819 offset = (session->pkt.tx * 7) - se_skcb->offset; 820 len = se_skb->len - offset; 821 if (len > 7) 822 len = 7; 823 824 if (offset + len > se_skb->len) { 825 netdev_err_once(priv->ndev, 826 "%s: 0x%p: requested data outside of queued buffer: offset %i, len %i, pkt.tx: %i\n", 827 __func__, session, se_skcb->offset, 828 se_skb->len , session->pkt.tx); 829 ret = -EOVERFLOW; 830 goto out_free; 831 } 832 833 if (!len) { 834 ret = -ENOBUFS; 835 break; 836 } 837 838 memcpy(&dat[1], &tpdat[offset], len); 839 ret = j1939_tp_tx_dat(session, dat, len + 1); 840 if (ret < 0) { 841 /* ENOBUFS == CAN interface TX queue is full */ 842 if (ret != -ENOBUFS) 843 netdev_alert(priv->ndev, 844 "%s: 0x%p: queue data error: %i\n", 845 __func__, session, ret); 846 break; 847 } 848 849 session->last_txcmd = 0xff; 850 pkt_done++; 851 session->pkt.tx++; 852 pdelay = j1939_cb_is_broadcast(&session->skcb) ? 50 : 853 j1939_tp_packet_delay; 854 855 if (session->pkt.tx < session->pkt.total && pdelay) { 856 j1939_tp_schedule_txtimer(session, pdelay); 857 break; 858 } 859 } 860 861 if (pkt_done) 862 j1939_tp_set_rxtimeout(session, 250); 863 864 out_free: 865 if (ret) 866 kfree_skb(se_skb); 867 else 868 consume_skb(se_skb); 869 870 return ret; 871 } 872 873 static int j1939_xtp_txnext_transmiter(struct j1939_session *session) 874 { 875 struct j1939_priv *priv = session->priv; 876 int ret = 0; 877 878 if (!j1939_tp_im_transmitter(&session->skcb)) { 879 netdev_alert(priv->ndev, "%s: 0x%p: called by not transmitter!\n", 880 __func__, session); 881 return -EINVAL; 882 } 883 884 switch (session->last_cmd) { 885 case 0: 886 ret = j1939_session_tx_rts(session); 887 break; 888 889 case J1939_ETP_CMD_CTS: 890 if (session->last_txcmd != J1939_ETP_CMD_DPO) { 891 ret = j1939_session_tx_dpo(session); 892 if (ret) 893 return ret; 894 } 895 896 fallthrough; 897 case J1939_TP_CMD_CTS: 898 case 0xff: /* did some data */ 899 case J1939_ETP_CMD_DPO: 900 case J1939_TP_CMD_BAM: 901 ret = j1939_session_tx_dat(session); 902 903 break; 904 default: 905 netdev_alert(priv->ndev, "%s: 0x%p: unexpected last_cmd: %x\n", 906 __func__, session, session->last_cmd); 907 } 908 909 return ret; 910 } 911 912 static int j1939_session_tx_cts(struct j1939_session *session) 913 { 914 struct j1939_priv *priv = session->priv; 915 unsigned int pkt, len; 916 int ret; 917 u8 dat[8]; 918 919 if (!j1939_sk_recv_match(priv, &session->skcb)) 920 return -ENOENT; 921 922 len = session->pkt.total - session->pkt.rx; 923 len = min3(len, session->pkt.block, j1939_tp_block ?: 255); 924 memset(dat, 0xff, sizeof(dat)); 925 926 if (session->skcb.addr.type == J1939_ETP) { 927 pkt = session->pkt.rx + 1; 928 dat[0] = J1939_ETP_CMD_CTS; 929 dat[1] = len; 930 dat[2] = (pkt >> 0); 931 dat[3] = (pkt >> 8); 932 dat[4] = (pkt >> 16); 933 } else { 934 dat[0] = J1939_TP_CMD_CTS; 935 dat[1] = len; 936 dat[2] = session->pkt.rx + 1; 937 } 938 939 if (dat[0] == session->last_txcmd) 940 /* done already */ 941 return 0; 942 943 ret = j1939_tp_tx_ctl(session, true, dat); 944 if (ret < 0) 945 return ret; 946 947 if (len) 948 /* only mark cts done when len is set */ 949 session->last_txcmd = dat[0]; 950 j1939_tp_set_rxtimeout(session, 1250); 951 952 netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); 953 954 return 0; 955 } 956 957 static int j1939_session_tx_eoma(struct j1939_session *session) 958 { 959 struct j1939_priv *priv = session->priv; 960 u8 dat[8]; 961 int ret; 962 963 if (!j1939_sk_recv_match(priv, &session->skcb)) 964 return -ENOENT; 965 966 memset(dat, 0xff, sizeof(dat)); 967 968 if (session->skcb.addr.type == J1939_ETP) { 969 dat[0] = J1939_ETP_CMD_EOMA; 970 dat[1] = session->total_message_size >> 0; 971 dat[2] = session->total_message_size >> 8; 972 dat[3] = session->total_message_size >> 16; 973 dat[4] = session->total_message_size >> 24; 974 } else { 975 dat[0] = J1939_TP_CMD_EOMA; 976 dat[1] = session->total_message_size; 977 dat[2] = session->total_message_size >> 8; 978 dat[3] = session->pkt.total; 979 } 980 981 if (dat[0] == session->last_txcmd) 982 /* done already */ 983 return 0; 984 985 ret = j1939_tp_tx_ctl(session, true, dat); 986 if (ret < 0) 987 return ret; 988 989 session->last_txcmd = dat[0]; 990 991 /* wait for the EOMA packet to come in */ 992 j1939_tp_set_rxtimeout(session, 1250); 993 994 netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); 995 996 return 0; 997 } 998 999 static int j1939_xtp_txnext_receiver(struct j1939_session *session) 1000 { 1001 struct j1939_priv *priv = session->priv; 1002 int ret = 0; 1003 1004 if (!j1939_tp_im_receiver(&session->skcb)) { 1005 netdev_alert(priv->ndev, "%s: 0x%p: called by not receiver!\n", 1006 __func__, session); 1007 return -EINVAL; 1008 } 1009 1010 switch (session->last_cmd) { 1011 case J1939_TP_CMD_RTS: 1012 case J1939_ETP_CMD_RTS: 1013 ret = j1939_session_tx_cts(session); 1014 break; 1015 1016 case J1939_ETP_CMD_CTS: 1017 case J1939_TP_CMD_CTS: 1018 case 0xff: /* did some data */ 1019 case J1939_ETP_CMD_DPO: 1020 if ((session->skcb.addr.type == J1939_TP && 1021 j1939_cb_is_broadcast(&session->skcb))) 1022 break; 1023 1024 if (session->pkt.rx >= session->pkt.total) { 1025 ret = j1939_session_tx_eoma(session); 1026 } else if (session->pkt.rx >= session->pkt.last) { 1027 session->last_txcmd = 0; 1028 ret = j1939_session_tx_cts(session); 1029 } 1030 break; 1031 default: 1032 netdev_alert(priv->ndev, "%s: 0x%p: unexpected last_cmd: %x\n", 1033 __func__, session, session->last_cmd); 1034 } 1035 1036 return ret; 1037 } 1038 1039 static int j1939_simple_txnext(struct j1939_session *session) 1040 { 1041 struct j1939_priv *priv = session->priv; 1042 struct sk_buff *se_skb = j1939_session_skb_get(session); 1043 struct sk_buff *skb; 1044 int ret; 1045 1046 if (!se_skb) 1047 return 0; 1048 1049 skb = skb_clone(se_skb, GFP_ATOMIC); 1050 if (!skb) { 1051 ret = -ENOMEM; 1052 goto out_free; 1053 } 1054 1055 can_skb_set_owner(skb, se_skb->sk); 1056 1057 j1939_tp_set_rxtimeout(session, J1939_SIMPLE_ECHO_TIMEOUT_MS); 1058 1059 ret = j1939_send_one(priv, skb); 1060 if (ret) 1061 goto out_free; 1062 1063 j1939_sk_errqueue(session, J1939_ERRQUEUE_TX_SCHED); 1064 j1939_sk_queue_activate_next(session); 1065 1066 out_free: 1067 if (ret) 1068 kfree_skb(se_skb); 1069 else 1070 consume_skb(se_skb); 1071 1072 return ret; 1073 } 1074 1075 static bool j1939_session_deactivate_locked(struct j1939_session *session) 1076 { 1077 bool active = false; 1078 1079 lockdep_assert_held(&session->priv->active_session_list_lock); 1080 1081 if (session->state >= J1939_SESSION_ACTIVE && 1082 session->state < J1939_SESSION_ACTIVE_MAX) { 1083 active = true; 1084 1085 list_del_init(&session->active_session_list_entry); 1086 session->state = J1939_SESSION_DONE; 1087 j1939_session_put(session); 1088 } 1089 1090 return active; 1091 } 1092 1093 static bool j1939_session_deactivate(struct j1939_session *session) 1094 { 1095 struct j1939_priv *priv = session->priv; 1096 bool active; 1097 1098 j1939_session_list_lock(priv); 1099 active = j1939_session_deactivate_locked(session); 1100 j1939_session_list_unlock(priv); 1101 1102 return active; 1103 } 1104 1105 static void 1106 j1939_session_deactivate_activate_next(struct j1939_session *session) 1107 { 1108 if (j1939_session_deactivate(session)) 1109 j1939_sk_queue_activate_next(session); 1110 } 1111 1112 static void __j1939_session_cancel(struct j1939_session *session, 1113 enum j1939_xtp_abort err) 1114 { 1115 struct j1939_priv *priv = session->priv; 1116 1117 WARN_ON_ONCE(!err); 1118 lockdep_assert_held(&session->priv->active_session_list_lock); 1119 1120 session->err = j1939_xtp_abort_to_errno(priv, err); 1121 session->state = J1939_SESSION_WAITING_ABORT; 1122 /* do not send aborts on incoming broadcasts */ 1123 if (!j1939_cb_is_broadcast(&session->skcb)) { 1124 j1939_xtp_tx_abort(priv, &session->skcb, 1125 !session->transmission, 1126 err, session->skcb.addr.pgn); 1127 } 1128 1129 if (session->sk) 1130 j1939_sk_send_loop_abort(session->sk, session->err); 1131 } 1132 1133 static void j1939_session_cancel(struct j1939_session *session, 1134 enum j1939_xtp_abort err) 1135 { 1136 j1939_session_list_lock(session->priv); 1137 1138 if (session->state >= J1939_SESSION_ACTIVE && 1139 session->state < J1939_SESSION_WAITING_ABORT) { 1140 j1939_tp_set_rxtimeout(session, J1939_XTP_ABORT_TIMEOUT_MS); 1141 __j1939_session_cancel(session, err); 1142 } 1143 1144 j1939_session_list_unlock(session->priv); 1145 1146 if (!session->sk) 1147 j1939_sk_errqueue(session, J1939_ERRQUEUE_RX_ABORT); 1148 } 1149 1150 static enum hrtimer_restart j1939_tp_txtimer(struct hrtimer *hrtimer) 1151 { 1152 struct j1939_session *session = 1153 container_of(hrtimer, struct j1939_session, txtimer); 1154 struct j1939_priv *priv = session->priv; 1155 int ret = 0; 1156 1157 if (session->skcb.addr.type == J1939_SIMPLE) { 1158 ret = j1939_simple_txnext(session); 1159 } else { 1160 if (session->transmission) 1161 ret = j1939_xtp_txnext_transmiter(session); 1162 else 1163 ret = j1939_xtp_txnext_receiver(session); 1164 } 1165 1166 switch (ret) { 1167 case -ENOBUFS: 1168 /* Retry limit is currently arbitrary chosen */ 1169 if (session->tx_retry < J1939_XTP_TX_RETRY_LIMIT) { 1170 session->tx_retry++; 1171 j1939_tp_schedule_txtimer(session, 1172 10 + get_random_u32_below(16)); 1173 } else { 1174 netdev_alert(priv->ndev, "%s: 0x%p: tx retry count reached\n", 1175 __func__, session); 1176 session->err = -ENETUNREACH; 1177 j1939_session_rxtimer_cancel(session); 1178 j1939_session_deactivate_activate_next(session); 1179 } 1180 break; 1181 case -ENETDOWN: 1182 /* In this case we should get a netdev_event(), all active 1183 * sessions will be cleared by j1939_cancel_active_session(). 1184 * So handle this as an error, but let 1185 * j1939_cancel_active_session() do the cleanup including 1186 * propagation of the error to user space. 1187 */ 1188 break; 1189 case -EOVERFLOW: 1190 j1939_session_cancel(session, J1939_XTP_ABORT_ECTS_TOO_BIG); 1191 break; 1192 case 0: 1193 session->tx_retry = 0; 1194 break; 1195 default: 1196 netdev_alert(priv->ndev, "%s: 0x%p: tx aborted with unknown reason: %i\n", 1197 __func__, session, ret); 1198 if (session->skcb.addr.type != J1939_SIMPLE) { 1199 j1939_session_cancel(session, J1939_XTP_ABORT_OTHER); 1200 } else { 1201 session->err = ret; 1202 j1939_session_rxtimer_cancel(session); 1203 j1939_session_deactivate_activate_next(session); 1204 } 1205 } 1206 1207 j1939_session_put(session); 1208 1209 return HRTIMER_NORESTART; 1210 } 1211 1212 static void j1939_session_completed(struct j1939_session *session) 1213 { 1214 struct sk_buff *se_skb; 1215 1216 if (!session->transmission) { 1217 se_skb = j1939_session_skb_get(session); 1218 /* distribute among j1939 receivers */ 1219 j1939_sk_recv(session->priv, se_skb); 1220 consume_skb(se_skb); 1221 } 1222 1223 j1939_session_deactivate_activate_next(session); 1224 } 1225 1226 static enum hrtimer_restart j1939_tp_rxtimer(struct hrtimer *hrtimer) 1227 { 1228 struct j1939_session *session = container_of(hrtimer, 1229 struct j1939_session, 1230 rxtimer); 1231 struct j1939_priv *priv = session->priv; 1232 1233 if (session->state == J1939_SESSION_WAITING_ABORT) { 1234 netdev_alert(priv->ndev, "%s: 0x%p: abort rx timeout. Force session deactivation\n", 1235 __func__, session); 1236 1237 j1939_session_deactivate_activate_next(session); 1238 1239 } else if (session->skcb.addr.type == J1939_SIMPLE) { 1240 netdev_alert(priv->ndev, "%s: 0x%p: Timeout. Failed to send simple message.\n", 1241 __func__, session); 1242 1243 /* The message is probably stuck in the CAN controller and can 1244 * be send as soon as CAN bus is in working state again. 1245 */ 1246 session->err = -ETIME; 1247 j1939_session_deactivate(session); 1248 } else { 1249 j1939_session_list_lock(session->priv); 1250 if (session->state >= J1939_SESSION_ACTIVE && 1251 session->state < J1939_SESSION_ACTIVE_MAX) { 1252 netdev_alert(priv->ndev, "%s: 0x%p: rx timeout, send abort\n", 1253 __func__, session); 1254 j1939_session_get(session); 1255 hrtimer_start(&session->rxtimer, 1256 ms_to_ktime(J1939_XTP_ABORT_TIMEOUT_MS), 1257 HRTIMER_MODE_REL_SOFT); 1258 __j1939_session_cancel(session, J1939_XTP_ABORT_TIMEOUT); 1259 } 1260 j1939_session_list_unlock(session->priv); 1261 1262 if (!session->sk) 1263 j1939_sk_errqueue(session, J1939_ERRQUEUE_RX_ABORT); 1264 } 1265 1266 j1939_session_put(session); 1267 1268 return HRTIMER_NORESTART; 1269 } 1270 1271 static bool j1939_xtp_rx_cmd_bad_pgn(struct j1939_session *session, 1272 const struct sk_buff *skb) 1273 { 1274 const struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); 1275 pgn_t pgn = j1939_xtp_ctl_to_pgn(skb->data); 1276 struct j1939_priv *priv = session->priv; 1277 enum j1939_xtp_abort abort = J1939_XTP_NO_ABORT; 1278 u8 cmd = skb->data[0]; 1279 1280 if (session->skcb.addr.pgn == pgn) 1281 return false; 1282 1283 switch (cmd) { 1284 case J1939_TP_CMD_BAM: 1285 abort = J1939_XTP_NO_ABORT; 1286 break; 1287 1288 case J1939_ETP_CMD_RTS: 1289 fallthrough; 1290 case J1939_TP_CMD_RTS: 1291 abort = J1939_XTP_ABORT_BUSY; 1292 break; 1293 1294 case J1939_ETP_CMD_CTS: 1295 fallthrough; 1296 case J1939_TP_CMD_CTS: 1297 abort = J1939_XTP_ABORT_ECTS_UNXPECTED_PGN; 1298 break; 1299 1300 case J1939_ETP_CMD_DPO: 1301 abort = J1939_XTP_ABORT_BAD_EDPO_PGN; 1302 break; 1303 1304 case J1939_ETP_CMD_EOMA: 1305 fallthrough; 1306 case J1939_TP_CMD_EOMA: 1307 abort = J1939_XTP_ABORT_OTHER; 1308 break; 1309 1310 case J1939_ETP_CMD_ABORT: /* && J1939_TP_CMD_ABORT */ 1311 abort = J1939_XTP_NO_ABORT; 1312 break; 1313 1314 default: 1315 WARN_ON_ONCE(1); 1316 break; 1317 } 1318 1319 netdev_warn(priv->ndev, "%s: 0x%p: CMD 0x%02x with PGN 0x%05x for running session with different PGN 0x%05x.\n", 1320 __func__, session, cmd, pgn, session->skcb.addr.pgn); 1321 if (abort != J1939_XTP_NO_ABORT) 1322 j1939_xtp_tx_abort(priv, skcb, true, abort, pgn); 1323 1324 return true; 1325 } 1326 1327 static void j1939_xtp_rx_abort_one(struct j1939_priv *priv, struct sk_buff *skb, 1328 bool reverse, bool transmitter) 1329 { 1330 struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); 1331 struct j1939_session *session; 1332 u8 abort = skb->data[1]; 1333 1334 session = j1939_session_get_by_addr(priv, &skcb->addr, reverse, 1335 transmitter); 1336 if (!session) 1337 return; 1338 1339 if (j1939_xtp_rx_cmd_bad_pgn(session, skb)) 1340 goto abort_put; 1341 1342 netdev_info(priv->ndev, "%s: 0x%p: 0x%05x: (%u) %s\n", __func__, 1343 session, j1939_xtp_ctl_to_pgn(skb->data), abort, 1344 j1939_xtp_abort_to_str(abort)); 1345 1346 j1939_session_timers_cancel(session); 1347 session->err = j1939_xtp_abort_to_errno(priv, abort); 1348 if (session->sk) 1349 j1939_sk_send_loop_abort(session->sk, session->err); 1350 else 1351 j1939_sk_errqueue(session, J1939_ERRQUEUE_RX_ABORT); 1352 j1939_session_deactivate_activate_next(session); 1353 1354 abort_put: 1355 j1939_session_put(session); 1356 } 1357 1358 /* abort packets may come in 2 directions */ 1359 static void 1360 j1939_xtp_rx_abort(struct j1939_priv *priv, struct sk_buff *skb, 1361 bool transmitter) 1362 { 1363 j1939_xtp_rx_abort_one(priv, skb, false, transmitter); 1364 j1939_xtp_rx_abort_one(priv, skb, true, transmitter); 1365 } 1366 1367 static void 1368 j1939_xtp_rx_eoma_one(struct j1939_session *session, struct sk_buff *skb) 1369 { 1370 struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); 1371 const u8 *dat; 1372 int len; 1373 1374 if (j1939_xtp_rx_cmd_bad_pgn(session, skb)) 1375 return; 1376 1377 dat = skb->data; 1378 1379 if (skcb->addr.type == J1939_ETP) 1380 len = j1939_etp_ctl_to_size(dat); 1381 else 1382 len = j1939_tp_ctl_to_size(dat); 1383 1384 if (session->total_message_size != len) { 1385 netdev_warn_once(session->priv->ndev, 1386 "%s: 0x%p: Incorrect size. Expected: %i; got: %i.\n", 1387 __func__, session, session->total_message_size, 1388 len); 1389 } 1390 1391 netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); 1392 1393 session->pkt.tx_acked = session->pkt.total; 1394 j1939_session_timers_cancel(session); 1395 /* transmitted without problems */ 1396 j1939_session_completed(session); 1397 } 1398 1399 static void 1400 j1939_xtp_rx_eoma(struct j1939_priv *priv, struct sk_buff *skb, 1401 bool transmitter) 1402 { 1403 struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); 1404 struct j1939_session *session; 1405 1406 session = j1939_session_get_by_addr(priv, &skcb->addr, true, 1407 transmitter); 1408 if (!session) 1409 return; 1410 1411 j1939_xtp_rx_eoma_one(session, skb); 1412 j1939_session_put(session); 1413 } 1414 1415 static void 1416 j1939_xtp_rx_cts_one(struct j1939_session *session, struct sk_buff *skb) 1417 { 1418 enum j1939_xtp_abort err = J1939_XTP_ABORT_FAULT; 1419 unsigned int pkt; 1420 const u8 *dat; 1421 1422 dat = skb->data; 1423 1424 if (j1939_xtp_rx_cmd_bad_pgn(session, skb)) 1425 return; 1426 1427 netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); 1428 1429 if (session->last_cmd == dat[0]) { 1430 err = J1939_XTP_ABORT_DUP_SEQ; 1431 goto out_session_cancel; 1432 } 1433 1434 if (session->skcb.addr.type == J1939_ETP) 1435 pkt = j1939_etp_ctl_to_packet(dat); 1436 else 1437 pkt = dat[2]; 1438 1439 if (!pkt) 1440 goto out_session_cancel; 1441 else if (dat[1] > session->pkt.block /* 0xff for etp */) 1442 goto out_session_cancel; 1443 1444 /* set packet counters only when not CTS(0) */ 1445 session->pkt.tx_acked = pkt - 1; 1446 j1939_session_skb_drop_old(session); 1447 session->pkt.last = session->pkt.tx_acked + dat[1]; 1448 if (session->pkt.last > session->pkt.total) 1449 /* safety measure */ 1450 session->pkt.last = session->pkt.total; 1451 /* TODO: do not set tx here, do it in txtimer */ 1452 session->pkt.tx = session->pkt.tx_acked; 1453 1454 session->last_cmd = dat[0]; 1455 if (dat[1]) { 1456 j1939_tp_set_rxtimeout(session, 1250); 1457 if (session->transmission) { 1458 if (session->pkt.tx_acked) 1459 j1939_sk_errqueue(session, 1460 J1939_ERRQUEUE_TX_SCHED); 1461 j1939_session_txtimer_cancel(session); 1462 j1939_tp_schedule_txtimer(session, 0); 1463 } 1464 } else { 1465 /* CTS(0) */ 1466 j1939_tp_set_rxtimeout(session, 550); 1467 } 1468 return; 1469 1470 out_session_cancel: 1471 j1939_session_timers_cancel(session); 1472 j1939_session_cancel(session, err); 1473 } 1474 1475 static void 1476 j1939_xtp_rx_cts(struct j1939_priv *priv, struct sk_buff *skb, bool transmitter) 1477 { 1478 struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); 1479 struct j1939_session *session; 1480 1481 session = j1939_session_get_by_addr(priv, &skcb->addr, true, 1482 transmitter); 1483 if (!session) 1484 return; 1485 j1939_xtp_rx_cts_one(session, skb); 1486 j1939_session_put(session); 1487 } 1488 1489 static struct j1939_session *j1939_session_new(struct j1939_priv *priv, 1490 struct sk_buff *skb, size_t size) 1491 { 1492 struct j1939_session *session; 1493 struct j1939_sk_buff_cb *skcb; 1494 1495 session = kzalloc(sizeof(*session), gfp_any()); 1496 if (!session) 1497 return NULL; 1498 1499 INIT_LIST_HEAD(&session->active_session_list_entry); 1500 INIT_LIST_HEAD(&session->sk_session_queue_entry); 1501 kref_init(&session->kref); 1502 1503 j1939_priv_get(priv); 1504 session->priv = priv; 1505 session->total_message_size = size; 1506 session->state = J1939_SESSION_NEW; 1507 1508 skb_queue_head_init(&session->skb_queue); 1509 skb_queue_tail(&session->skb_queue, skb_get(skb)); 1510 1511 skcb = j1939_skb_to_cb(skb); 1512 memcpy(&session->skcb, skcb, sizeof(session->skcb)); 1513 1514 hrtimer_setup(&session->txtimer, j1939_tp_txtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT); 1515 hrtimer_setup(&session->rxtimer, j1939_tp_rxtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT); 1516 1517 netdev_dbg(priv->ndev, "%s: 0x%p: sa: %02x, da: %02x\n", 1518 __func__, session, skcb->addr.sa, skcb->addr.da); 1519 1520 return session; 1521 } 1522 1523 static struct 1524 j1939_session *j1939_session_fresh_new(struct j1939_priv *priv, 1525 int size, 1526 const struct j1939_sk_buff_cb *rel_skcb) 1527 { 1528 struct sk_buff *skb; 1529 struct j1939_sk_buff_cb *skcb; 1530 struct j1939_session *session; 1531 1532 skb = alloc_skb(size + sizeof(struct can_skb_priv), GFP_ATOMIC); 1533 if (unlikely(!skb)) 1534 return NULL; 1535 1536 skb->dev = priv->ndev; 1537 can_skb_reserve(skb); 1538 can_skb_prv(skb)->ifindex = priv->ndev->ifindex; 1539 can_skb_prv(skb)->skbcnt = 0; 1540 skcb = j1939_skb_to_cb(skb); 1541 memcpy(skcb, rel_skcb, sizeof(*skcb)); 1542 1543 session = j1939_session_new(priv, skb, size); 1544 if (!session) { 1545 kfree_skb(skb); 1546 return NULL; 1547 } 1548 1549 /* alloc data area */ 1550 skb_put(skb, size); 1551 /* skb is recounted in j1939_session_new() */ 1552 return session; 1553 } 1554 1555 int j1939_session_activate(struct j1939_session *session) 1556 { 1557 struct j1939_priv *priv = session->priv; 1558 struct j1939_session *active = NULL; 1559 int ret = 0; 1560 1561 j1939_session_list_lock(priv); 1562 if (session->skcb.addr.type != J1939_SIMPLE) 1563 active = j1939_session_get_by_addr_locked(priv, 1564 &priv->active_session_list, 1565 &session->skcb.addr, false, 1566 session->transmission); 1567 if (active) { 1568 j1939_session_put(active); 1569 ret = -EAGAIN; 1570 } else if (priv->ndev->reg_state != NETREG_REGISTERED) { 1571 ret = -ENODEV; 1572 } else { 1573 WARN_ON_ONCE(session->state != J1939_SESSION_NEW); 1574 list_add_tail(&session->active_session_list_entry, 1575 &priv->active_session_list); 1576 j1939_session_get(session); 1577 session->state = J1939_SESSION_ACTIVE; 1578 1579 netdev_dbg(session->priv->ndev, "%s: 0x%p\n", 1580 __func__, session); 1581 } 1582 j1939_session_list_unlock(priv); 1583 1584 return ret; 1585 } 1586 1587 static struct 1588 j1939_session *j1939_xtp_rx_rts_session_new(struct j1939_priv *priv, 1589 struct sk_buff *skb) 1590 { 1591 enum j1939_xtp_abort abort = J1939_XTP_NO_ABORT; 1592 struct j1939_sk_buff_cb skcb = *j1939_skb_to_cb(skb); 1593 struct j1939_session *session; 1594 const u8 *dat; 1595 int len, ret; 1596 pgn_t pgn; 1597 1598 netdev_dbg(priv->ndev, "%s\n", __func__); 1599 1600 dat = skb->data; 1601 pgn = j1939_xtp_ctl_to_pgn(dat); 1602 skcb.addr.pgn = pgn; 1603 1604 if (!j1939_sk_recv_match(priv, &skcb)) 1605 return NULL; 1606 1607 if (skcb.addr.type == J1939_ETP) { 1608 len = j1939_etp_ctl_to_size(dat); 1609 if (len > J1939_MAX_ETP_PACKET_SIZE) 1610 abort = J1939_XTP_ABORT_FAULT; 1611 else if (len > priv->tp_max_packet_size) 1612 abort = J1939_XTP_ABORT_RESOURCE; 1613 else if (len <= J1939_MAX_TP_PACKET_SIZE) 1614 abort = J1939_XTP_ABORT_FAULT; 1615 } else { 1616 len = j1939_tp_ctl_to_size(dat); 1617 if (len > J1939_MAX_TP_PACKET_SIZE) 1618 abort = J1939_XTP_ABORT_FAULT; 1619 else if (len > priv->tp_max_packet_size) 1620 abort = J1939_XTP_ABORT_RESOURCE; 1621 else if (len < J1939_MIN_TP_PACKET_SIZE) 1622 abort = J1939_XTP_ABORT_FAULT; 1623 } 1624 1625 if (abort != J1939_XTP_NO_ABORT) { 1626 j1939_xtp_tx_abort(priv, &skcb, true, abort, pgn); 1627 return NULL; 1628 } 1629 1630 session = j1939_session_fresh_new(priv, len, &skcb); 1631 if (!session) { 1632 j1939_xtp_tx_abort(priv, &skcb, true, 1633 J1939_XTP_ABORT_RESOURCE, pgn); 1634 return NULL; 1635 } 1636 1637 /* initialize the control buffer: plain copy */ 1638 session->pkt.total = (len + 6) / 7; 1639 session->pkt.block = 0xff; 1640 if (skcb.addr.type != J1939_ETP) { 1641 if (dat[3] != session->pkt.total) 1642 netdev_alert(priv->ndev, "%s: 0x%p: strange total, %u != %u\n", 1643 __func__, session, session->pkt.total, 1644 dat[3]); 1645 session->pkt.total = dat[3]; 1646 session->pkt.block = min(dat[3], dat[4]); 1647 } 1648 1649 session->pkt.rx = 0; 1650 session->pkt.tx = 0; 1651 1652 session->tskey = priv->rx_tskey++; 1653 j1939_sk_errqueue(session, J1939_ERRQUEUE_RX_RTS); 1654 1655 ret = j1939_session_activate(session); 1656 if (ret) { 1657 /* Entering this scope indicates an issue with the J1939 bus. 1658 * Possible scenarios include: 1659 * - A time lapse occurred, and a new session was initiated 1660 * due to another packet being sent correctly. This could 1661 * have been caused by too long interrupt, debugger, or being 1662 * out-scheduled by another task. 1663 * - The bus is receiving numerous erroneous packets, either 1664 * from a malfunctioning device or during a test scenario. 1665 */ 1666 netdev_alert(priv->ndev, "%s: 0x%p: concurrent session with same addr (%02x %02x) is already active.\n", 1667 __func__, session, skcb.addr.sa, skcb.addr.da); 1668 j1939_session_put(session); 1669 return NULL; 1670 } 1671 1672 return session; 1673 } 1674 1675 static int j1939_xtp_rx_rts_session_active(struct j1939_session *session, 1676 struct sk_buff *skb) 1677 { 1678 struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); 1679 struct j1939_priv *priv = session->priv; 1680 1681 if (!session->transmission) { 1682 if (j1939_xtp_rx_cmd_bad_pgn(session, skb)) 1683 return -EBUSY; 1684 1685 /* RTS on active session */ 1686 j1939_session_timers_cancel(session); 1687 j1939_session_cancel(session, J1939_XTP_ABORT_BUSY); 1688 } 1689 1690 if (session->last_cmd != 0) { 1691 /* we received a second rts on the same connection */ 1692 netdev_alert(priv->ndev, "%s: 0x%p: connection exists (%02x %02x). last cmd: %x\n", 1693 __func__, session, skcb->addr.sa, skcb->addr.da, 1694 session->last_cmd); 1695 1696 j1939_session_timers_cancel(session); 1697 j1939_session_cancel(session, J1939_XTP_ABORT_BUSY); 1698 if (session->transmission) 1699 j1939_session_deactivate_activate_next(session); 1700 1701 return -EBUSY; 1702 } 1703 1704 if (session->skcb.addr.sa != skcb->addr.sa || 1705 session->skcb.addr.da != skcb->addr.da) 1706 netdev_warn(priv->ndev, "%s: 0x%p: session->skcb.addr.sa=0x%02x skcb->addr.sa=0x%02x session->skcb.addr.da=0x%02x skcb->addr.da=0x%02x\n", 1707 __func__, session, 1708 session->skcb.addr.sa, skcb->addr.sa, 1709 session->skcb.addr.da, skcb->addr.da); 1710 /* make sure 'sa' & 'da' are correct ! 1711 * They may be 'not filled in yet' for sending 1712 * skb's, since they did not pass the Address Claim ever. 1713 */ 1714 session->skcb.addr.sa = skcb->addr.sa; 1715 session->skcb.addr.da = skcb->addr.da; 1716 1717 netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); 1718 1719 return 0; 1720 } 1721 1722 static void j1939_xtp_rx_rts(struct j1939_priv *priv, struct sk_buff *skb, 1723 bool transmitter) 1724 { 1725 struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); 1726 struct j1939_session *session; 1727 u8 cmd = skb->data[0]; 1728 1729 session = j1939_session_get_by_addr(priv, &skcb->addr, false, 1730 transmitter); 1731 1732 if (!session) { 1733 if (transmitter) { 1734 /* If we're the transmitter and this function is called, 1735 * we received our own RTS. A session has already been 1736 * created. 1737 * 1738 * For some reasons however it might have been destroyed 1739 * already. So don't create a new one here (using 1740 * "j1939_xtp_rx_rts_session_new()") as this will be a 1741 * receiver session. 1742 * 1743 * The reasons the session is already destroyed might 1744 * be: 1745 * - user space closed socket was and the session was 1746 * aborted 1747 * - session was aborted due to external abort message 1748 */ 1749 return; 1750 } 1751 session = j1939_xtp_rx_rts_session_new(priv, skb); 1752 if (!session) { 1753 if (cmd == J1939_TP_CMD_BAM && j1939_sk_recv_match(priv, skcb)) 1754 netdev_info(priv->ndev, "%s: failed to create TP BAM session\n", 1755 __func__); 1756 return; 1757 } 1758 } else { 1759 if (j1939_xtp_rx_rts_session_active(session, skb)) { 1760 j1939_session_put(session); 1761 return; 1762 } 1763 } 1764 session->last_cmd = cmd; 1765 1766 if (cmd == J1939_TP_CMD_BAM) { 1767 if (!session->transmission) 1768 j1939_tp_set_rxtimeout(session, 750); 1769 } else { 1770 if (!session->transmission) { 1771 j1939_session_txtimer_cancel(session); 1772 j1939_tp_schedule_txtimer(session, 0); 1773 } 1774 j1939_tp_set_rxtimeout(session, 1250); 1775 } 1776 1777 j1939_session_put(session); 1778 } 1779 1780 static void j1939_xtp_rx_dpo_one(struct j1939_session *session, 1781 struct sk_buff *skb) 1782 { 1783 const u8 *dat = skb->data; 1784 1785 if (j1939_xtp_rx_cmd_bad_pgn(session, skb)) 1786 return; 1787 1788 netdev_dbg(session->priv->ndev, "%s: 0x%p\n", __func__, session); 1789 1790 /* transmitted without problems */ 1791 session->pkt.dpo = j1939_etp_ctl_to_packet(skb->data); 1792 session->last_cmd = dat[0]; 1793 j1939_tp_set_rxtimeout(session, 750); 1794 1795 if (!session->transmission) 1796 j1939_sk_errqueue(session, J1939_ERRQUEUE_RX_DPO); 1797 } 1798 1799 static void j1939_xtp_rx_dpo(struct j1939_priv *priv, struct sk_buff *skb, 1800 bool transmitter) 1801 { 1802 struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); 1803 struct j1939_session *session; 1804 1805 session = j1939_session_get_by_addr(priv, &skcb->addr, false, 1806 transmitter); 1807 if (!session) { 1808 netdev_info(priv->ndev, 1809 "%s: no connection found\n", __func__); 1810 return; 1811 } 1812 1813 j1939_xtp_rx_dpo_one(session, skb); 1814 j1939_session_put(session); 1815 } 1816 1817 static void j1939_xtp_rx_dat_one(struct j1939_session *session, 1818 struct sk_buff *skb) 1819 { 1820 enum j1939_xtp_abort abort = J1939_XTP_ABORT_FAULT; 1821 struct j1939_priv *priv = session->priv; 1822 struct j1939_sk_buff_cb *skcb, *se_skcb; 1823 struct sk_buff *se_skb = NULL; 1824 const u8 *dat; 1825 u8 *tpdat; 1826 int offset; 1827 int nbytes; 1828 bool final = false; 1829 bool remain = false; 1830 bool do_cts_eoma = false; 1831 int packet; 1832 1833 skcb = j1939_skb_to_cb(skb); 1834 dat = skb->data; 1835 if (skb->len != 8) { 1836 /* makes no sense */ 1837 abort = J1939_XTP_ABORT_UNEXPECTED_DATA; 1838 goto out_session_cancel; 1839 } 1840 1841 switch (session->last_cmd) { 1842 case 0xff: 1843 break; 1844 case J1939_ETP_CMD_DPO: 1845 if (skcb->addr.type == J1939_ETP) 1846 break; 1847 fallthrough; 1848 case J1939_TP_CMD_BAM: 1849 fallthrough; 1850 case J1939_TP_CMD_CTS: 1851 if (skcb->addr.type != J1939_ETP) 1852 break; 1853 fallthrough; 1854 default: 1855 netdev_info(priv->ndev, "%s: 0x%p: last %02x\n", __func__, 1856 session, session->last_cmd); 1857 goto out_session_cancel; 1858 } 1859 1860 packet = (dat[0] - 1 + session->pkt.dpo); 1861 if (packet > session->pkt.total || 1862 (session->pkt.rx + 1) > session->pkt.total) { 1863 netdev_info(priv->ndev, "%s: 0x%p: should have been completed\n", 1864 __func__, session); 1865 goto out_session_cancel; 1866 } 1867 1868 se_skb = j1939_session_skb_get_by_offset(session, packet * 7); 1869 if (!se_skb) { 1870 netdev_warn(priv->ndev, "%s: 0x%p: no skb found\n", __func__, 1871 session); 1872 goto out_session_cancel; 1873 } 1874 1875 se_skcb = j1939_skb_to_cb(se_skb); 1876 offset = packet * 7 - se_skcb->offset; 1877 nbytes = se_skb->len - offset; 1878 if (nbytes > 7) 1879 nbytes = 7; 1880 if (nbytes <= 0 || (nbytes + 1) > skb->len) { 1881 netdev_info(priv->ndev, "%s: 0x%p: nbytes %i, len %i\n", 1882 __func__, session, nbytes, skb->len); 1883 goto out_session_cancel; 1884 } 1885 1886 tpdat = se_skb->data; 1887 if (!session->transmission) { 1888 memcpy(&tpdat[offset], &dat[1], nbytes); 1889 } else { 1890 int err; 1891 1892 err = memcmp(&tpdat[offset], &dat[1], nbytes); 1893 if (err) 1894 netdev_err_once(priv->ndev, 1895 "%s: 0x%p: Data of RX-looped back packet (%*ph) doesn't match TX data (%*ph)!\n", 1896 __func__, session, 1897 nbytes, &dat[1], 1898 nbytes, &tpdat[offset]); 1899 } 1900 1901 if (packet == session->pkt.rx) 1902 session->pkt.rx++; 1903 1904 if (se_skcb->addr.type != J1939_ETP && 1905 j1939_cb_is_broadcast(&session->skcb)) { 1906 if (session->pkt.rx >= session->pkt.total) 1907 final = true; 1908 else 1909 remain = true; 1910 } else { 1911 /* never final, an EOMA must follow */ 1912 if (session->pkt.rx >= session->pkt.last) 1913 do_cts_eoma = true; 1914 } 1915 1916 if (final) { 1917 j1939_session_timers_cancel(session); 1918 j1939_session_completed(session); 1919 } else if (remain) { 1920 if (!session->transmission) 1921 j1939_tp_set_rxtimeout(session, 750); 1922 } else if (do_cts_eoma) { 1923 j1939_tp_set_rxtimeout(session, 1250); 1924 if (!session->transmission) 1925 j1939_tp_schedule_txtimer(session, 0); 1926 } else { 1927 j1939_tp_set_rxtimeout(session, 750); 1928 } 1929 session->last_cmd = 0xff; 1930 consume_skb(se_skb); 1931 j1939_session_put(session); 1932 1933 return; 1934 1935 out_session_cancel: 1936 kfree_skb(se_skb); 1937 j1939_session_timers_cancel(session); 1938 j1939_session_cancel(session, abort); 1939 j1939_session_put(session); 1940 } 1941 1942 static void j1939_xtp_rx_dat(struct j1939_priv *priv, struct sk_buff *skb) 1943 { 1944 struct j1939_sk_buff_cb *skcb; 1945 struct j1939_session *session; 1946 1947 skcb = j1939_skb_to_cb(skb); 1948 1949 if (j1939_tp_im_transmitter(skcb)) { 1950 session = j1939_session_get_by_addr(priv, &skcb->addr, false, 1951 true); 1952 if (!session) 1953 netdev_info(priv->ndev, "%s: no tx connection found\n", 1954 __func__); 1955 else 1956 j1939_xtp_rx_dat_one(session, skb); 1957 } 1958 1959 if (j1939_tp_im_receiver(skcb)) { 1960 session = j1939_session_get_by_addr(priv, &skcb->addr, false, 1961 false); 1962 if (!session) 1963 netdev_info(priv->ndev, "%s: no rx connection found\n", 1964 __func__); 1965 else 1966 j1939_xtp_rx_dat_one(session, skb); 1967 } 1968 1969 if (j1939_cb_is_broadcast(skcb)) { 1970 session = j1939_session_get_by_addr(priv, &skcb->addr, false, 1971 false); 1972 if (session) 1973 j1939_xtp_rx_dat_one(session, skb); 1974 } 1975 } 1976 1977 /* j1939 main intf */ 1978 struct j1939_session *j1939_tp_send(struct j1939_priv *priv, 1979 struct sk_buff *skb, size_t size) 1980 { 1981 struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); 1982 struct j1939_session *session; 1983 int ret; 1984 1985 if (skcb->addr.pgn == J1939_TP_PGN_DAT || 1986 skcb->addr.pgn == J1939_TP_PGN_CTL || 1987 skcb->addr.pgn == J1939_ETP_PGN_DAT || 1988 skcb->addr.pgn == J1939_ETP_PGN_CTL) 1989 /* avoid conflict */ 1990 return ERR_PTR(-EDOM); 1991 1992 if (size > priv->tp_max_packet_size) 1993 return ERR_PTR(-EMSGSIZE); 1994 1995 if (size <= 8) 1996 skcb->addr.type = J1939_SIMPLE; 1997 else if (size > J1939_MAX_TP_PACKET_SIZE) 1998 skcb->addr.type = J1939_ETP; 1999 else 2000 skcb->addr.type = J1939_TP; 2001 2002 if (skcb->addr.type == J1939_ETP && 2003 j1939_cb_is_broadcast(skcb)) 2004 return ERR_PTR(-EDESTADDRREQ); 2005 2006 /* fill in addresses from names */ 2007 ret = j1939_ac_fixup(priv, skb); 2008 if (unlikely(ret)) 2009 return ERR_PTR(ret); 2010 2011 /* fix DST flags, it may be used there soon */ 2012 if (j1939_address_is_unicast(skcb->addr.da) && 2013 priv->ents[skcb->addr.da].nusers) 2014 skcb->flags |= J1939_ECU_LOCAL_DST; 2015 2016 /* src is always local, I'm sending ... */ 2017 skcb->flags |= J1939_ECU_LOCAL_SRC; 2018 2019 /* prepare new session */ 2020 session = j1939_session_new(priv, skb, size); 2021 if (!session) 2022 return ERR_PTR(-ENOMEM); 2023 2024 /* skb is recounted in j1939_session_new() */ 2025 sock_hold(skb->sk); 2026 session->sk = skb->sk; 2027 session->transmission = true; 2028 session->pkt.total = (size + 6) / 7; 2029 session->pkt.block = skcb->addr.type == J1939_ETP ? 255 : 2030 min(j1939_tp_block ?: 255, session->pkt.total); 2031 2032 if (j1939_cb_is_broadcast(&session->skcb)) 2033 /* set the end-packet for broadcast */ 2034 session->pkt.last = session->pkt.total; 2035 2036 skcb->tskey = atomic_inc_return(&session->sk->sk_tskey) - 1; 2037 session->tskey = skcb->tskey; 2038 2039 return session; 2040 } 2041 2042 static void j1939_tp_cmd_recv(struct j1939_priv *priv, struct sk_buff *skb) 2043 { 2044 struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); 2045 int extd = J1939_TP; 2046 u8 cmd = skb->data[0]; 2047 2048 switch (cmd) { 2049 case J1939_ETP_CMD_RTS: 2050 extd = J1939_ETP; 2051 fallthrough; 2052 case J1939_TP_CMD_BAM: 2053 if (cmd == J1939_TP_CMD_BAM && !j1939_cb_is_broadcast(skcb)) { 2054 netdev_err_once(priv->ndev, "%s: BAM to unicast (%02x), ignoring!\n", 2055 __func__, skcb->addr.sa); 2056 return; 2057 } 2058 fallthrough; 2059 case J1939_TP_CMD_RTS: 2060 if (skcb->addr.type != extd) 2061 return; 2062 2063 if (cmd == J1939_TP_CMD_RTS && j1939_cb_is_broadcast(skcb)) { 2064 netdev_alert(priv->ndev, "%s: rts without destination (%02x)\n", 2065 __func__, skcb->addr.sa); 2066 return; 2067 } 2068 2069 if (j1939_tp_im_transmitter(skcb)) 2070 j1939_xtp_rx_rts(priv, skb, true); 2071 2072 if (j1939_tp_im_receiver(skcb) || j1939_cb_is_broadcast(skcb)) 2073 j1939_xtp_rx_rts(priv, skb, false); 2074 2075 break; 2076 2077 case J1939_ETP_CMD_CTS: 2078 extd = J1939_ETP; 2079 fallthrough; 2080 case J1939_TP_CMD_CTS: 2081 if (skcb->addr.type != extd) 2082 return; 2083 2084 if (j1939_tp_im_transmitter(skcb)) 2085 j1939_xtp_rx_cts(priv, skb, false); 2086 2087 if (j1939_tp_im_receiver(skcb)) 2088 j1939_xtp_rx_cts(priv, skb, true); 2089 2090 break; 2091 2092 case J1939_ETP_CMD_DPO: 2093 if (skcb->addr.type != J1939_ETP) 2094 return; 2095 2096 if (j1939_tp_im_transmitter(skcb)) 2097 j1939_xtp_rx_dpo(priv, skb, true); 2098 2099 if (j1939_tp_im_receiver(skcb)) 2100 j1939_xtp_rx_dpo(priv, skb, false); 2101 2102 break; 2103 2104 case J1939_ETP_CMD_EOMA: 2105 extd = J1939_ETP; 2106 fallthrough; 2107 case J1939_TP_CMD_EOMA: 2108 if (skcb->addr.type != extd) 2109 return; 2110 2111 if (j1939_tp_im_transmitter(skcb)) 2112 j1939_xtp_rx_eoma(priv, skb, false); 2113 2114 if (j1939_tp_im_receiver(skcb)) 2115 j1939_xtp_rx_eoma(priv, skb, true); 2116 2117 break; 2118 2119 case J1939_ETP_CMD_ABORT: /* && J1939_TP_CMD_ABORT */ 2120 if (j1939_cb_is_broadcast(skcb)) { 2121 netdev_err_once(priv->ndev, "%s: abort to broadcast (%02x), ignoring!\n", 2122 __func__, skcb->addr.sa); 2123 return; 2124 } 2125 2126 if (j1939_tp_im_transmitter(skcb)) 2127 j1939_xtp_rx_abort(priv, skb, true); 2128 2129 if (j1939_tp_im_receiver(skcb)) 2130 j1939_xtp_rx_abort(priv, skb, false); 2131 2132 break; 2133 default: 2134 return; 2135 } 2136 } 2137 2138 int j1939_tp_recv(struct j1939_priv *priv, struct sk_buff *skb) 2139 { 2140 struct j1939_sk_buff_cb *skcb = j1939_skb_to_cb(skb); 2141 2142 if (!j1939_tp_im_involved_anydir(skcb) && !j1939_cb_is_broadcast(skcb)) 2143 return 0; 2144 2145 switch (skcb->addr.pgn) { 2146 case J1939_ETP_PGN_DAT: 2147 skcb->addr.type = J1939_ETP; 2148 fallthrough; 2149 case J1939_TP_PGN_DAT: 2150 j1939_xtp_rx_dat(priv, skb); 2151 break; 2152 2153 case J1939_ETP_PGN_CTL: 2154 skcb->addr.type = J1939_ETP; 2155 fallthrough; 2156 case J1939_TP_PGN_CTL: 2157 if (skb->len < 8) 2158 return 0; /* Don't care. Nothing to extract here */ 2159 2160 j1939_tp_cmd_recv(priv, skb); 2161 break; 2162 default: 2163 return 0; /* no problem */ 2164 } 2165 return 1; /* "I processed the message" */ 2166 } 2167 2168 void j1939_simple_recv(struct j1939_priv *priv, struct sk_buff *skb) 2169 { 2170 struct j1939_session *session; 2171 2172 if (!skb->sk) 2173 return; 2174 2175 if (skb->sk->sk_family != AF_CAN || 2176 skb->sk->sk_protocol != CAN_J1939) 2177 return; 2178 2179 j1939_session_list_lock(priv); 2180 session = j1939_session_get_simple(priv, skb); 2181 j1939_session_list_unlock(priv); 2182 if (!session) { 2183 netdev_warn(priv->ndev, 2184 "%s: Received already invalidated message\n", 2185 __func__); 2186 return; 2187 } 2188 2189 j1939_session_timers_cancel(session); 2190 j1939_session_deactivate(session); 2191 j1939_session_put(session); 2192 } 2193 2194 int j1939_cancel_active_session(struct j1939_priv *priv, struct sock *sk) 2195 { 2196 struct j1939_session *session, *saved; 2197 2198 netdev_dbg(priv->ndev, "%s, sk: %p\n", __func__, sk); 2199 j1939_session_list_lock(priv); 2200 list_for_each_entry_safe(session, saved, 2201 &priv->active_session_list, 2202 active_session_list_entry) { 2203 if (!sk || sk == session->sk) { 2204 if (hrtimer_try_to_cancel(&session->txtimer) == 1) 2205 j1939_session_put(session); 2206 if (hrtimer_try_to_cancel(&session->rxtimer) == 1) 2207 j1939_session_put(session); 2208 2209 session->err = ESHUTDOWN; 2210 j1939_session_deactivate_locked(session); 2211 } 2212 } 2213 j1939_session_list_unlock(priv); 2214 return NOTIFY_DONE; 2215 } 2216 2217 void j1939_tp_init(struct j1939_priv *priv) 2218 { 2219 spin_lock_init(&priv->active_session_list_lock); 2220 INIT_LIST_HEAD(&priv->active_session_list); 2221 priv->tp_max_packet_size = J1939_MAX_ETP_PACKET_SIZE; 2222 } 2223