1 // SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) 2 /* isotp.c - ISO 15765-2 CAN transport protocol for protocol family CAN 3 * 4 * This implementation does not provide ISO-TP specific return values to the 5 * userspace. 6 * 7 * - RX path timeout of data reception leads to -ETIMEDOUT 8 * - RX path SN mismatch leads to -EILSEQ 9 * - RX path data reception with wrong padding leads to -EBADMSG 10 * - TX path flowcontrol reception timeout leads to -ECOMM 11 * - TX path flowcontrol reception overflow leads to -EMSGSIZE 12 * - TX path flowcontrol reception with wrong layout/padding leads to -EBADMSG 13 * - when a transfer (tx) is on the run the next write() blocks until it's done 14 * - use CAN_ISOTP_WAIT_TX_DONE flag to block the caller until the PDU is sent 15 * - as we have static buffers the check whether the PDU fits into the buffer 16 * is done at FF reception time (no support for sending 'wait frames') 17 * - take care of the tx-queue-len as traffic shaping is still on the TODO list 18 * 19 * Copyright (c) 2020 Volkswagen Group Electronic Research 20 * All rights reserved. 21 * 22 * Redistribution and use in source and binary forms, with or without 23 * modification, are permitted provided that the following conditions 24 * are met: 25 * 1. Redistributions of source code must retain the above copyright 26 * notice, this list of conditions and the following disclaimer. 27 * 2. Redistributions in binary form must reproduce the above copyright 28 * notice, this list of conditions and the following disclaimer in the 29 * documentation and/or other materials provided with the distribution. 30 * 3. Neither the name of Volkswagen nor the names of its contributors 31 * may be used to endorse or promote products derived from this software 32 * without specific prior written permission. 33 * 34 * Alternatively, provided that this notice is retained in full, this 35 * software may be distributed under the terms of the GNU General 36 * Public License ("GPL") version 2, in which case the provisions of the 37 * GPL apply INSTEAD OF those given above. 38 * 39 * The provided data structures and external interfaces from this code 40 * are not restricted to be used by modules with a GPL compatible license. 41 * 42 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 43 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 44 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 45 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 46 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 47 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 48 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 49 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 50 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 51 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 52 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH 53 * DAMAGE. 54 */ 55 56 #include <linux/module.h> 57 #include <linux/init.h> 58 #include <linux/interrupt.h> 59 #include <linux/hrtimer.h> 60 #include <linux/wait.h> 61 #include <linux/uio.h> 62 #include <linux/net.h> 63 #include <linux/netdevice.h> 64 #include <linux/socket.h> 65 #include <linux/if_arp.h> 66 #include <linux/skbuff.h> 67 #include <linux/can.h> 68 #include <linux/can/core.h> 69 #include <linux/can/skb.h> 70 #include <linux/can/isotp.h> 71 #include <linux/slab.h> 72 #include <net/sock.h> 73 #include <net/net_namespace.h> 74 75 MODULE_DESCRIPTION("PF_CAN isotp 15765-2:2016 protocol"); 76 MODULE_LICENSE("Dual BSD/GPL"); 77 MODULE_AUTHOR("Oliver Hartkopp <socketcan@hartkopp.net>"); 78 MODULE_ALIAS("can-proto-6"); 79 80 #define ISOTP_MIN_NAMELEN CAN_REQUIRED_SIZE(struct sockaddr_can, can_addr.tp) 81 82 #define SINGLE_MASK(id) (((id) & CAN_EFF_FLAG) ? \ 83 (CAN_EFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG) : \ 84 (CAN_SFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG)) 85 86 /* ISO 15765-2:2016 supports more than 4095 byte per ISO PDU as the FF_DL can 87 * take full 32 bit values (4 Gbyte). We would need some good concept to handle 88 * this between user space and kernel space. For now increase the static buffer 89 * to something about 8 kbyte to be able to test this new functionality. 90 */ 91 #define MAX_MSG_LENGTH 8200 92 93 /* N_PCI type values in bits 7-4 of N_PCI bytes */ 94 #define N_PCI_SF 0x00 /* single frame */ 95 #define N_PCI_FF 0x10 /* first frame */ 96 #define N_PCI_CF 0x20 /* consecutive frame */ 97 #define N_PCI_FC 0x30 /* flow control */ 98 99 #define N_PCI_SZ 1 /* size of the PCI byte #1 */ 100 #define SF_PCI_SZ4 1 /* size of SingleFrame PCI including 4 bit SF_DL */ 101 #define SF_PCI_SZ8 2 /* size of SingleFrame PCI including 8 bit SF_DL */ 102 #define FF_PCI_SZ12 2 /* size of FirstFrame PCI including 12 bit FF_DL */ 103 #define FF_PCI_SZ32 6 /* size of FirstFrame PCI including 32 bit FF_DL */ 104 #define FC_CONTENT_SZ 3 /* flow control content size in byte (FS/BS/STmin) */ 105 106 #define ISOTP_CHECK_PADDING (CAN_ISOTP_CHK_PAD_LEN | CAN_ISOTP_CHK_PAD_DATA) 107 108 /* Flow Status given in FC frame */ 109 #define ISOTP_FC_CTS 0 /* clear to send */ 110 #define ISOTP_FC_WT 1 /* wait */ 111 #define ISOTP_FC_OVFLW 2 /* overflow */ 112 113 enum { 114 ISOTP_IDLE = 0, 115 ISOTP_WAIT_FIRST_FC, 116 ISOTP_WAIT_FC, 117 ISOTP_WAIT_DATA, 118 ISOTP_SENDING 119 }; 120 121 struct tpcon { 122 int idx; 123 int len; 124 u8 state; 125 u8 bs; 126 u8 sn; 127 u8 ll_dl; 128 u8 buf[MAX_MSG_LENGTH + 1]; 129 }; 130 131 struct isotp_sock { 132 struct sock sk; 133 int bound; 134 int ifindex; 135 canid_t txid; 136 canid_t rxid; 137 ktime_t tx_gap; 138 ktime_t lastrxcf_tstamp; 139 struct hrtimer rxtimer, txtimer; 140 struct can_isotp_options opt; 141 struct can_isotp_fc_options rxfc, txfc; 142 struct can_isotp_ll_options ll; 143 u32 force_tx_stmin; 144 u32 force_rx_stmin; 145 struct tpcon rx, tx; 146 struct list_head notifier; 147 wait_queue_head_t wait; 148 }; 149 150 static LIST_HEAD(isotp_notifier_list); 151 static DEFINE_SPINLOCK(isotp_notifier_lock); 152 static struct isotp_sock *isotp_busy_notifier; 153 154 static inline struct isotp_sock *isotp_sk(const struct sock *sk) 155 { 156 return (struct isotp_sock *)sk; 157 } 158 159 static enum hrtimer_restart isotp_rx_timer_handler(struct hrtimer *hrtimer) 160 { 161 struct isotp_sock *so = container_of(hrtimer, struct isotp_sock, 162 rxtimer); 163 struct sock *sk = &so->sk; 164 165 if (so->rx.state == ISOTP_WAIT_DATA) { 166 /* we did not get new data frames in time */ 167 168 /* report 'connection timed out' */ 169 sk->sk_err = ETIMEDOUT; 170 if (!sock_flag(sk, SOCK_DEAD)) 171 sk->sk_error_report(sk); 172 173 /* reset rx state */ 174 so->rx.state = ISOTP_IDLE; 175 } 176 177 return HRTIMER_NORESTART; 178 } 179 180 static int isotp_send_fc(struct sock *sk, int ae, u8 flowstatus) 181 { 182 struct net_device *dev; 183 struct sk_buff *nskb; 184 struct canfd_frame *ncf; 185 struct isotp_sock *so = isotp_sk(sk); 186 int can_send_ret; 187 188 nskb = alloc_skb(so->ll.mtu + sizeof(struct can_skb_priv), gfp_any()); 189 if (!nskb) 190 return 1; 191 192 dev = dev_get_by_index(sock_net(sk), so->ifindex); 193 if (!dev) { 194 kfree_skb(nskb); 195 return 1; 196 } 197 198 can_skb_reserve(nskb); 199 can_skb_prv(nskb)->ifindex = dev->ifindex; 200 can_skb_prv(nskb)->skbcnt = 0; 201 202 nskb->dev = dev; 203 can_skb_set_owner(nskb, sk); 204 ncf = (struct canfd_frame *)nskb->data; 205 skb_put_zero(nskb, so->ll.mtu); 206 207 /* create & send flow control reply */ 208 ncf->can_id = so->txid; 209 210 if (so->opt.flags & CAN_ISOTP_TX_PADDING) { 211 memset(ncf->data, so->opt.txpad_content, CAN_MAX_DLEN); 212 ncf->len = CAN_MAX_DLEN; 213 } else { 214 ncf->len = ae + FC_CONTENT_SZ; 215 } 216 217 ncf->data[ae] = N_PCI_FC | flowstatus; 218 ncf->data[ae + 1] = so->rxfc.bs; 219 ncf->data[ae + 2] = so->rxfc.stmin; 220 221 if (ae) 222 ncf->data[0] = so->opt.ext_address; 223 224 ncf->flags = so->ll.tx_flags; 225 226 can_send_ret = can_send(nskb, 1); 227 if (can_send_ret) 228 pr_notice_once("can-isotp: %s: can_send_ret %d\n", 229 __func__, can_send_ret); 230 231 dev_put(dev); 232 233 /* reset blocksize counter */ 234 so->rx.bs = 0; 235 236 /* reset last CF frame rx timestamp for rx stmin enforcement */ 237 so->lastrxcf_tstamp = ktime_set(0, 0); 238 239 /* start rx timeout watchdog */ 240 hrtimer_start(&so->rxtimer, ktime_set(1, 0), HRTIMER_MODE_REL_SOFT); 241 return 0; 242 } 243 244 static void isotp_rcv_skb(struct sk_buff *skb, struct sock *sk) 245 { 246 struct sockaddr_can *addr = (struct sockaddr_can *)skb->cb; 247 248 BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct sockaddr_can)); 249 250 memset(addr, 0, sizeof(*addr)); 251 addr->can_family = AF_CAN; 252 addr->can_ifindex = skb->dev->ifindex; 253 254 if (sock_queue_rcv_skb(sk, skb) < 0) 255 kfree_skb(skb); 256 } 257 258 static u8 padlen(u8 datalen) 259 { 260 static const u8 plen[] = { 261 8, 8, 8, 8, 8, 8, 8, 8, 8, /* 0 - 8 */ 262 12, 12, 12, 12, /* 9 - 12 */ 263 16, 16, 16, 16, /* 13 - 16 */ 264 20, 20, 20, 20, /* 17 - 20 */ 265 24, 24, 24, 24, /* 21 - 24 */ 266 32, 32, 32, 32, 32, 32, 32, 32, /* 25 - 32 */ 267 48, 48, 48, 48, 48, 48, 48, 48, /* 33 - 40 */ 268 48, 48, 48, 48, 48, 48, 48, 48 /* 41 - 48 */ 269 }; 270 271 if (datalen > 48) 272 return 64; 273 274 return plen[datalen]; 275 } 276 277 /* check for length optimization and return 1/true when the check fails */ 278 static int check_optimized(struct canfd_frame *cf, int start_index) 279 { 280 /* for CAN_DL <= 8 the start_index is equal to the CAN_DL as the 281 * padding would start at this point. E.g. if the padding would 282 * start at cf.data[7] cf->len has to be 7 to be optimal. 283 * Note: The data[] index starts with zero. 284 */ 285 if (cf->len <= CAN_MAX_DLEN) 286 return (cf->len != start_index); 287 288 /* This relation is also valid in the non-linear DLC range, where 289 * we need to take care of the minimal next possible CAN_DL. 290 * The correct check would be (padlen(cf->len) != padlen(start_index)). 291 * But as cf->len can only take discrete values from 12, .., 64 at this 292 * point the padlen(cf->len) is always equal to cf->len. 293 */ 294 return (cf->len != padlen(start_index)); 295 } 296 297 /* check padding and return 1/true when the check fails */ 298 static int check_pad(struct isotp_sock *so, struct canfd_frame *cf, 299 int start_index, u8 content) 300 { 301 int i; 302 303 /* no RX_PADDING value => check length of optimized frame length */ 304 if (!(so->opt.flags & CAN_ISOTP_RX_PADDING)) { 305 if (so->opt.flags & CAN_ISOTP_CHK_PAD_LEN) 306 return check_optimized(cf, start_index); 307 308 /* no valid test against empty value => ignore frame */ 309 return 1; 310 } 311 312 /* check datalength of correctly padded CAN frame */ 313 if ((so->opt.flags & CAN_ISOTP_CHK_PAD_LEN) && 314 cf->len != padlen(cf->len)) 315 return 1; 316 317 /* check padding content */ 318 if (so->opt.flags & CAN_ISOTP_CHK_PAD_DATA) { 319 for (i = start_index; i < cf->len; i++) 320 if (cf->data[i] != content) 321 return 1; 322 } 323 return 0; 324 } 325 326 static int isotp_rcv_fc(struct isotp_sock *so, struct canfd_frame *cf, int ae) 327 { 328 struct sock *sk = &so->sk; 329 330 if (so->tx.state != ISOTP_WAIT_FC && 331 so->tx.state != ISOTP_WAIT_FIRST_FC) 332 return 0; 333 334 hrtimer_cancel(&so->txtimer); 335 336 if ((cf->len < ae + FC_CONTENT_SZ) || 337 ((so->opt.flags & ISOTP_CHECK_PADDING) && 338 check_pad(so, cf, ae + FC_CONTENT_SZ, so->opt.rxpad_content))) { 339 /* malformed PDU - report 'not a data message' */ 340 sk->sk_err = EBADMSG; 341 if (!sock_flag(sk, SOCK_DEAD)) 342 sk->sk_error_report(sk); 343 344 so->tx.state = ISOTP_IDLE; 345 wake_up_interruptible(&so->wait); 346 return 1; 347 } 348 349 /* get communication parameters only from the first FC frame */ 350 if (so->tx.state == ISOTP_WAIT_FIRST_FC) { 351 so->txfc.bs = cf->data[ae + 1]; 352 so->txfc.stmin = cf->data[ae + 2]; 353 354 /* fix wrong STmin values according spec */ 355 if (so->txfc.stmin > 0x7F && 356 (so->txfc.stmin < 0xF1 || so->txfc.stmin > 0xF9)) 357 so->txfc.stmin = 0x7F; 358 359 so->tx_gap = ktime_set(0, 0); 360 /* add transmission time for CAN frame N_As */ 361 so->tx_gap = ktime_add_ns(so->tx_gap, so->opt.frame_txtime); 362 /* add waiting time for consecutive frames N_Cs */ 363 if (so->opt.flags & CAN_ISOTP_FORCE_TXSTMIN) 364 so->tx_gap = ktime_add_ns(so->tx_gap, 365 so->force_tx_stmin); 366 else if (so->txfc.stmin < 0x80) 367 so->tx_gap = ktime_add_ns(so->tx_gap, 368 so->txfc.stmin * 1000000); 369 else 370 so->tx_gap = ktime_add_ns(so->tx_gap, 371 (so->txfc.stmin - 0xF0) 372 * 100000); 373 so->tx.state = ISOTP_WAIT_FC; 374 } 375 376 switch (cf->data[ae] & 0x0F) { 377 case ISOTP_FC_CTS: 378 so->tx.bs = 0; 379 so->tx.state = ISOTP_SENDING; 380 /* start cyclic timer for sending CF frame */ 381 hrtimer_start(&so->txtimer, so->tx_gap, 382 HRTIMER_MODE_REL_SOFT); 383 break; 384 385 case ISOTP_FC_WT: 386 /* start timer to wait for next FC frame */ 387 hrtimer_start(&so->txtimer, ktime_set(1, 0), 388 HRTIMER_MODE_REL_SOFT); 389 break; 390 391 case ISOTP_FC_OVFLW: 392 /* overflow on receiver side - report 'message too long' */ 393 sk->sk_err = EMSGSIZE; 394 if (!sock_flag(sk, SOCK_DEAD)) 395 sk->sk_error_report(sk); 396 fallthrough; 397 398 default: 399 /* stop this tx job */ 400 so->tx.state = ISOTP_IDLE; 401 wake_up_interruptible(&so->wait); 402 } 403 return 0; 404 } 405 406 static int isotp_rcv_sf(struct sock *sk, struct canfd_frame *cf, int pcilen, 407 struct sk_buff *skb, int len) 408 { 409 struct isotp_sock *so = isotp_sk(sk); 410 struct sk_buff *nskb; 411 412 hrtimer_cancel(&so->rxtimer); 413 so->rx.state = ISOTP_IDLE; 414 415 if (!len || len > cf->len - pcilen) 416 return 1; 417 418 if ((so->opt.flags & ISOTP_CHECK_PADDING) && 419 check_pad(so, cf, pcilen + len, so->opt.rxpad_content)) { 420 /* malformed PDU - report 'not a data message' */ 421 sk->sk_err = EBADMSG; 422 if (!sock_flag(sk, SOCK_DEAD)) 423 sk->sk_error_report(sk); 424 return 1; 425 } 426 427 nskb = alloc_skb(len, gfp_any()); 428 if (!nskb) 429 return 1; 430 431 memcpy(skb_put(nskb, len), &cf->data[pcilen], len); 432 433 nskb->tstamp = skb->tstamp; 434 nskb->dev = skb->dev; 435 isotp_rcv_skb(nskb, sk); 436 return 0; 437 } 438 439 static int isotp_rcv_ff(struct sock *sk, struct canfd_frame *cf, int ae) 440 { 441 struct isotp_sock *so = isotp_sk(sk); 442 int i; 443 int off; 444 int ff_pci_sz; 445 446 hrtimer_cancel(&so->rxtimer); 447 so->rx.state = ISOTP_IDLE; 448 449 /* get the used sender LL_DL from the (first) CAN frame data length */ 450 so->rx.ll_dl = padlen(cf->len); 451 452 /* the first frame has to use the entire frame up to LL_DL length */ 453 if (cf->len != so->rx.ll_dl) 454 return 1; 455 456 /* get the FF_DL */ 457 so->rx.len = (cf->data[ae] & 0x0F) << 8; 458 so->rx.len += cf->data[ae + 1]; 459 460 /* Check for FF_DL escape sequence supporting 32 bit PDU length */ 461 if (so->rx.len) { 462 ff_pci_sz = FF_PCI_SZ12; 463 } else { 464 /* FF_DL = 0 => get real length from next 4 bytes */ 465 so->rx.len = cf->data[ae + 2] << 24; 466 so->rx.len += cf->data[ae + 3] << 16; 467 so->rx.len += cf->data[ae + 4] << 8; 468 so->rx.len += cf->data[ae + 5]; 469 ff_pci_sz = FF_PCI_SZ32; 470 } 471 472 /* take care of a potential SF_DL ESC offset for TX_DL > 8 */ 473 off = (so->rx.ll_dl > CAN_MAX_DLEN) ? 1 : 0; 474 475 if (so->rx.len + ae + off + ff_pci_sz < so->rx.ll_dl) 476 return 1; 477 478 if (so->rx.len > MAX_MSG_LENGTH) { 479 /* send FC frame with overflow status */ 480 isotp_send_fc(sk, ae, ISOTP_FC_OVFLW); 481 return 1; 482 } 483 484 /* copy the first received data bytes */ 485 so->rx.idx = 0; 486 for (i = ae + ff_pci_sz; i < so->rx.ll_dl; i++) 487 so->rx.buf[so->rx.idx++] = cf->data[i]; 488 489 /* initial setup for this pdu reception */ 490 so->rx.sn = 1; 491 so->rx.state = ISOTP_WAIT_DATA; 492 493 /* no creation of flow control frames */ 494 if (so->opt.flags & CAN_ISOTP_LISTEN_MODE) 495 return 0; 496 497 /* send our first FC frame */ 498 isotp_send_fc(sk, ae, ISOTP_FC_CTS); 499 return 0; 500 } 501 502 static int isotp_rcv_cf(struct sock *sk, struct canfd_frame *cf, int ae, 503 struct sk_buff *skb) 504 { 505 struct isotp_sock *so = isotp_sk(sk); 506 struct sk_buff *nskb; 507 int i; 508 509 if (so->rx.state != ISOTP_WAIT_DATA) 510 return 0; 511 512 /* drop if timestamp gap is less than force_rx_stmin nano secs */ 513 if (so->opt.flags & CAN_ISOTP_FORCE_RXSTMIN) { 514 if (ktime_to_ns(ktime_sub(skb->tstamp, so->lastrxcf_tstamp)) < 515 so->force_rx_stmin) 516 return 0; 517 518 so->lastrxcf_tstamp = skb->tstamp; 519 } 520 521 hrtimer_cancel(&so->rxtimer); 522 523 /* CFs are never longer than the FF */ 524 if (cf->len > so->rx.ll_dl) 525 return 1; 526 527 /* CFs have usually the LL_DL length */ 528 if (cf->len < so->rx.ll_dl) { 529 /* this is only allowed for the last CF */ 530 if (so->rx.len - so->rx.idx > so->rx.ll_dl - ae - N_PCI_SZ) 531 return 1; 532 } 533 534 if ((cf->data[ae] & 0x0F) != so->rx.sn) { 535 /* wrong sn detected - report 'illegal byte sequence' */ 536 sk->sk_err = EILSEQ; 537 if (!sock_flag(sk, SOCK_DEAD)) 538 sk->sk_error_report(sk); 539 540 /* reset rx state */ 541 so->rx.state = ISOTP_IDLE; 542 return 1; 543 } 544 so->rx.sn++; 545 so->rx.sn %= 16; 546 547 for (i = ae + N_PCI_SZ; i < cf->len; i++) { 548 so->rx.buf[so->rx.idx++] = cf->data[i]; 549 if (so->rx.idx >= so->rx.len) 550 break; 551 } 552 553 if (so->rx.idx >= so->rx.len) { 554 /* we are done */ 555 so->rx.state = ISOTP_IDLE; 556 557 if ((so->opt.flags & ISOTP_CHECK_PADDING) && 558 check_pad(so, cf, i + 1, so->opt.rxpad_content)) { 559 /* malformed PDU - report 'not a data message' */ 560 sk->sk_err = EBADMSG; 561 if (!sock_flag(sk, SOCK_DEAD)) 562 sk->sk_error_report(sk); 563 return 1; 564 } 565 566 nskb = alloc_skb(so->rx.len, gfp_any()); 567 if (!nskb) 568 return 1; 569 570 memcpy(skb_put(nskb, so->rx.len), so->rx.buf, 571 so->rx.len); 572 573 nskb->tstamp = skb->tstamp; 574 nskb->dev = skb->dev; 575 isotp_rcv_skb(nskb, sk); 576 return 0; 577 } 578 579 /* perform blocksize handling, if enabled */ 580 if (!so->rxfc.bs || ++so->rx.bs < so->rxfc.bs) { 581 /* start rx timeout watchdog */ 582 hrtimer_start(&so->rxtimer, ktime_set(1, 0), 583 HRTIMER_MODE_REL_SOFT); 584 return 0; 585 } 586 587 /* no creation of flow control frames */ 588 if (so->opt.flags & CAN_ISOTP_LISTEN_MODE) 589 return 0; 590 591 /* we reached the specified blocksize so->rxfc.bs */ 592 isotp_send_fc(sk, ae, ISOTP_FC_CTS); 593 return 0; 594 } 595 596 static void isotp_rcv(struct sk_buff *skb, void *data) 597 { 598 struct sock *sk = (struct sock *)data; 599 struct isotp_sock *so = isotp_sk(sk); 600 struct canfd_frame *cf; 601 int ae = (so->opt.flags & CAN_ISOTP_EXTEND_ADDR) ? 1 : 0; 602 u8 n_pci_type, sf_dl; 603 604 /* Strictly receive only frames with the configured MTU size 605 * => clear separation of CAN2.0 / CAN FD transport channels 606 */ 607 if (skb->len != so->ll.mtu) 608 return; 609 610 cf = (struct canfd_frame *)skb->data; 611 612 /* if enabled: check reception of my configured extended address */ 613 if (ae && cf->data[0] != so->opt.rx_ext_address) 614 return; 615 616 n_pci_type = cf->data[ae] & 0xF0; 617 618 if (so->opt.flags & CAN_ISOTP_HALF_DUPLEX) { 619 /* check rx/tx path half duplex expectations */ 620 if ((so->tx.state != ISOTP_IDLE && n_pci_type != N_PCI_FC) || 621 (so->rx.state != ISOTP_IDLE && n_pci_type == N_PCI_FC)) 622 return; 623 } 624 625 switch (n_pci_type) { 626 case N_PCI_FC: 627 /* tx path: flow control frame containing the FC parameters */ 628 isotp_rcv_fc(so, cf, ae); 629 break; 630 631 case N_PCI_SF: 632 /* rx path: single frame 633 * 634 * As we do not have a rx.ll_dl configuration, we can only test 635 * if the CAN frames payload length matches the LL_DL == 8 636 * requirements - no matter if it's CAN 2.0 or CAN FD 637 */ 638 639 /* get the SF_DL from the N_PCI byte */ 640 sf_dl = cf->data[ae] & 0x0F; 641 642 if (cf->len <= CAN_MAX_DLEN) { 643 isotp_rcv_sf(sk, cf, SF_PCI_SZ4 + ae, skb, sf_dl); 644 } else { 645 if (skb->len == CANFD_MTU) { 646 /* We have a CAN FD frame and CAN_DL is greater than 8: 647 * Only frames with the SF_DL == 0 ESC value are valid. 648 * 649 * If so take care of the increased SF PCI size 650 * (SF_PCI_SZ8) to point to the message content behind 651 * the extended SF PCI info and get the real SF_DL 652 * length value from the formerly first data byte. 653 */ 654 if (sf_dl == 0) 655 isotp_rcv_sf(sk, cf, SF_PCI_SZ8 + ae, skb, 656 cf->data[SF_PCI_SZ4 + ae]); 657 } 658 } 659 break; 660 661 case N_PCI_FF: 662 /* rx path: first frame */ 663 isotp_rcv_ff(sk, cf, ae); 664 break; 665 666 case N_PCI_CF: 667 /* rx path: consecutive frame */ 668 isotp_rcv_cf(sk, cf, ae, skb); 669 break; 670 } 671 } 672 673 static void isotp_fill_dataframe(struct canfd_frame *cf, struct isotp_sock *so, 674 int ae, int off) 675 { 676 int pcilen = N_PCI_SZ + ae + off; 677 int space = so->tx.ll_dl - pcilen; 678 int num = min_t(int, so->tx.len - so->tx.idx, space); 679 int i; 680 681 cf->can_id = so->txid; 682 cf->len = num + pcilen; 683 684 if (num < space) { 685 if (so->opt.flags & CAN_ISOTP_TX_PADDING) { 686 /* user requested padding */ 687 cf->len = padlen(cf->len); 688 memset(cf->data, so->opt.txpad_content, cf->len); 689 } else if (cf->len > CAN_MAX_DLEN) { 690 /* mandatory padding for CAN FD frames */ 691 cf->len = padlen(cf->len); 692 memset(cf->data, CAN_ISOTP_DEFAULT_PAD_CONTENT, 693 cf->len); 694 } 695 } 696 697 for (i = 0; i < num; i++) 698 cf->data[pcilen + i] = so->tx.buf[so->tx.idx++]; 699 700 if (ae) 701 cf->data[0] = so->opt.ext_address; 702 } 703 704 static void isotp_create_fframe(struct canfd_frame *cf, struct isotp_sock *so, 705 int ae) 706 { 707 int i; 708 int ff_pci_sz; 709 710 cf->can_id = so->txid; 711 cf->len = so->tx.ll_dl; 712 if (ae) 713 cf->data[0] = so->opt.ext_address; 714 715 /* create N_PCI bytes with 12/32 bit FF_DL data length */ 716 if (so->tx.len > 4095) { 717 /* use 32 bit FF_DL notation */ 718 cf->data[ae] = N_PCI_FF; 719 cf->data[ae + 1] = 0; 720 cf->data[ae + 2] = (u8)(so->tx.len >> 24) & 0xFFU; 721 cf->data[ae + 3] = (u8)(so->tx.len >> 16) & 0xFFU; 722 cf->data[ae + 4] = (u8)(so->tx.len >> 8) & 0xFFU; 723 cf->data[ae + 5] = (u8)so->tx.len & 0xFFU; 724 ff_pci_sz = FF_PCI_SZ32; 725 } else { 726 /* use 12 bit FF_DL notation */ 727 cf->data[ae] = (u8)(so->tx.len >> 8) | N_PCI_FF; 728 cf->data[ae + 1] = (u8)so->tx.len & 0xFFU; 729 ff_pci_sz = FF_PCI_SZ12; 730 } 731 732 /* add first data bytes depending on ae */ 733 for (i = ae + ff_pci_sz; i < so->tx.ll_dl; i++) 734 cf->data[i] = so->tx.buf[so->tx.idx++]; 735 736 so->tx.sn = 1; 737 so->tx.state = ISOTP_WAIT_FIRST_FC; 738 } 739 740 static enum hrtimer_restart isotp_tx_timer_handler(struct hrtimer *hrtimer) 741 { 742 struct isotp_sock *so = container_of(hrtimer, struct isotp_sock, 743 txtimer); 744 struct sock *sk = &so->sk; 745 struct sk_buff *skb; 746 struct net_device *dev; 747 struct canfd_frame *cf; 748 enum hrtimer_restart restart = HRTIMER_NORESTART; 749 int can_send_ret; 750 int ae = (so->opt.flags & CAN_ISOTP_EXTEND_ADDR) ? 1 : 0; 751 752 switch (so->tx.state) { 753 case ISOTP_WAIT_FC: 754 case ISOTP_WAIT_FIRST_FC: 755 756 /* we did not get any flow control frame in time */ 757 758 /* report 'communication error on send' */ 759 sk->sk_err = ECOMM; 760 if (!sock_flag(sk, SOCK_DEAD)) 761 sk->sk_error_report(sk); 762 763 /* reset tx state */ 764 so->tx.state = ISOTP_IDLE; 765 wake_up_interruptible(&so->wait); 766 break; 767 768 case ISOTP_SENDING: 769 770 /* push out the next segmented pdu */ 771 dev = dev_get_by_index(sock_net(sk), so->ifindex); 772 if (!dev) 773 break; 774 775 isotp_tx_burst: 776 skb = alloc_skb(so->ll.mtu + sizeof(struct can_skb_priv), 777 GFP_ATOMIC); 778 if (!skb) { 779 dev_put(dev); 780 break; 781 } 782 783 can_skb_reserve(skb); 784 can_skb_prv(skb)->ifindex = dev->ifindex; 785 can_skb_prv(skb)->skbcnt = 0; 786 787 cf = (struct canfd_frame *)skb->data; 788 skb_put_zero(skb, so->ll.mtu); 789 790 /* create consecutive frame */ 791 isotp_fill_dataframe(cf, so, ae, 0); 792 793 /* place consecutive frame N_PCI in appropriate index */ 794 cf->data[ae] = N_PCI_CF | so->tx.sn++; 795 so->tx.sn %= 16; 796 so->tx.bs++; 797 798 cf->flags = so->ll.tx_flags; 799 800 skb->dev = dev; 801 can_skb_set_owner(skb, sk); 802 803 can_send_ret = can_send(skb, 1); 804 if (can_send_ret) 805 pr_notice_once("can-isotp: %s: can_send_ret %d\n", 806 __func__, can_send_ret); 807 808 if (so->tx.idx >= so->tx.len) { 809 /* we are done */ 810 so->tx.state = ISOTP_IDLE; 811 dev_put(dev); 812 wake_up_interruptible(&so->wait); 813 break; 814 } 815 816 if (so->txfc.bs && so->tx.bs >= so->txfc.bs) { 817 /* stop and wait for FC */ 818 so->tx.state = ISOTP_WAIT_FC; 819 dev_put(dev); 820 hrtimer_set_expires(&so->txtimer, 821 ktime_add(ktime_get(), 822 ktime_set(1, 0))); 823 restart = HRTIMER_RESTART; 824 break; 825 } 826 827 /* no gap between data frames needed => use burst mode */ 828 if (!so->tx_gap) 829 goto isotp_tx_burst; 830 831 /* start timer to send next data frame with correct delay */ 832 dev_put(dev); 833 hrtimer_set_expires(&so->txtimer, 834 ktime_add(ktime_get(), so->tx_gap)); 835 restart = HRTIMER_RESTART; 836 break; 837 838 default: 839 WARN_ON_ONCE(1); 840 } 841 842 return restart; 843 } 844 845 static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) 846 { 847 struct sock *sk = sock->sk; 848 struct isotp_sock *so = isotp_sk(sk); 849 struct sk_buff *skb; 850 struct net_device *dev; 851 struct canfd_frame *cf; 852 int ae = (so->opt.flags & CAN_ISOTP_EXTEND_ADDR) ? 1 : 0; 853 int wait_tx_done = (so->opt.flags & CAN_ISOTP_WAIT_TX_DONE) ? 1 : 0; 854 int off; 855 int err; 856 857 if (!so->bound) 858 return -EADDRNOTAVAIL; 859 860 /* we do not support multiple buffers - for now */ 861 if (so->tx.state != ISOTP_IDLE || wq_has_sleeper(&so->wait)) { 862 if (msg->msg_flags & MSG_DONTWAIT) 863 return -EAGAIN; 864 865 /* wait for complete transmission of current pdu */ 866 wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE); 867 } 868 869 if (!size || size > MAX_MSG_LENGTH) 870 return -EINVAL; 871 872 /* take care of a potential SF_DL ESC offset for TX_DL > 8 */ 873 off = (so->tx.ll_dl > CAN_MAX_DLEN) ? 1 : 0; 874 875 /* does the given data fit into a single frame for SF_BROADCAST? */ 876 if ((so->opt.flags & CAN_ISOTP_SF_BROADCAST) && 877 (size > so->tx.ll_dl - SF_PCI_SZ4 - ae - off)) 878 return -EINVAL; 879 880 err = memcpy_from_msg(so->tx.buf, msg, size); 881 if (err < 0) 882 return err; 883 884 dev = dev_get_by_index(sock_net(sk), so->ifindex); 885 if (!dev) 886 return -ENXIO; 887 888 skb = sock_alloc_send_skb(sk, so->ll.mtu + sizeof(struct can_skb_priv), 889 msg->msg_flags & MSG_DONTWAIT, &err); 890 if (!skb) { 891 dev_put(dev); 892 return err; 893 } 894 895 can_skb_reserve(skb); 896 can_skb_prv(skb)->ifindex = dev->ifindex; 897 can_skb_prv(skb)->skbcnt = 0; 898 899 so->tx.state = ISOTP_SENDING; 900 so->tx.len = size; 901 so->tx.idx = 0; 902 903 cf = (struct canfd_frame *)skb->data; 904 skb_put_zero(skb, so->ll.mtu); 905 906 /* check for single frame transmission depending on TX_DL */ 907 if (size <= so->tx.ll_dl - SF_PCI_SZ4 - ae - off) { 908 /* The message size generally fits into a SingleFrame - good. 909 * 910 * SF_DL ESC offset optimization: 911 * 912 * When TX_DL is greater 8 but the message would still fit 913 * into a 8 byte CAN frame, we can omit the offset. 914 * This prevents a protocol caused length extension from 915 * CAN_DL = 8 to CAN_DL = 12 due to the SF_SL ESC handling. 916 */ 917 if (size <= CAN_MAX_DLEN - SF_PCI_SZ4 - ae) 918 off = 0; 919 920 isotp_fill_dataframe(cf, so, ae, off); 921 922 /* place single frame N_PCI w/o length in appropriate index */ 923 cf->data[ae] = N_PCI_SF; 924 925 /* place SF_DL size value depending on the SF_DL ESC offset */ 926 if (off) 927 cf->data[SF_PCI_SZ4 + ae] = size; 928 else 929 cf->data[ae] |= size; 930 931 so->tx.state = ISOTP_IDLE; 932 wake_up_interruptible(&so->wait); 933 934 /* don't enable wait queue for a single frame transmission */ 935 wait_tx_done = 0; 936 } else { 937 /* send first frame and wait for FC */ 938 939 isotp_create_fframe(cf, so, ae); 940 941 /* start timeout for FC */ 942 hrtimer_start(&so->txtimer, ktime_set(1, 0), HRTIMER_MODE_REL_SOFT); 943 } 944 945 /* send the first or only CAN frame */ 946 cf->flags = so->ll.tx_flags; 947 948 skb->dev = dev; 949 skb->sk = sk; 950 err = can_send(skb, 1); 951 dev_put(dev); 952 if (err) { 953 pr_notice_once("can-isotp: %s: can_send_ret %d\n", 954 __func__, err); 955 return err; 956 } 957 958 if (wait_tx_done) { 959 /* wait for complete transmission of current pdu */ 960 wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE); 961 } 962 963 return size; 964 } 965 966 static int isotp_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 967 int flags) 968 { 969 struct sock *sk = sock->sk; 970 struct sk_buff *skb; 971 int err = 0; 972 int noblock; 973 974 noblock = flags & MSG_DONTWAIT; 975 flags &= ~MSG_DONTWAIT; 976 977 skb = skb_recv_datagram(sk, flags, noblock, &err); 978 if (!skb) 979 return err; 980 981 if (size < skb->len) 982 msg->msg_flags |= MSG_TRUNC; 983 else 984 size = skb->len; 985 986 err = memcpy_to_msg(msg, skb->data, size); 987 if (err < 0) { 988 skb_free_datagram(sk, skb); 989 return err; 990 } 991 992 sock_recv_timestamp(msg, sk, skb); 993 994 if (msg->msg_name) { 995 __sockaddr_check_size(ISOTP_MIN_NAMELEN); 996 msg->msg_namelen = ISOTP_MIN_NAMELEN; 997 memcpy(msg->msg_name, skb->cb, msg->msg_namelen); 998 } 999 1000 skb_free_datagram(sk, skb); 1001 1002 return size; 1003 } 1004 1005 static int isotp_release(struct socket *sock) 1006 { 1007 struct sock *sk = sock->sk; 1008 struct isotp_sock *so; 1009 struct net *net; 1010 1011 if (!sk) 1012 return 0; 1013 1014 so = isotp_sk(sk); 1015 net = sock_net(sk); 1016 1017 /* wait for complete transmission of current pdu */ 1018 wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE); 1019 1020 spin_lock(&isotp_notifier_lock); 1021 while (isotp_busy_notifier == so) { 1022 spin_unlock(&isotp_notifier_lock); 1023 schedule_timeout_uninterruptible(1); 1024 spin_lock(&isotp_notifier_lock); 1025 } 1026 list_del(&so->notifier); 1027 spin_unlock(&isotp_notifier_lock); 1028 1029 lock_sock(sk); 1030 1031 hrtimer_cancel(&so->txtimer); 1032 hrtimer_cancel(&so->rxtimer); 1033 1034 /* remove current filters & unregister */ 1035 if (so->bound && (!(so->opt.flags & CAN_ISOTP_SF_BROADCAST))) { 1036 if (so->ifindex) { 1037 struct net_device *dev; 1038 1039 dev = dev_get_by_index(net, so->ifindex); 1040 if (dev) { 1041 can_rx_unregister(net, dev, so->rxid, 1042 SINGLE_MASK(so->rxid), 1043 isotp_rcv, sk); 1044 dev_put(dev); 1045 } 1046 } 1047 } 1048 1049 so->ifindex = 0; 1050 so->bound = 0; 1051 1052 sock_orphan(sk); 1053 sock->sk = NULL; 1054 1055 release_sock(sk); 1056 sock_put(sk); 1057 1058 return 0; 1059 } 1060 1061 static int isotp_bind(struct socket *sock, struct sockaddr *uaddr, int len) 1062 { 1063 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; 1064 struct sock *sk = sock->sk; 1065 struct isotp_sock *so = isotp_sk(sk); 1066 struct net *net = sock_net(sk); 1067 int ifindex; 1068 struct net_device *dev; 1069 int err = 0; 1070 int notify_enetdown = 0; 1071 int do_rx_reg = 1; 1072 1073 if (len < ISOTP_MIN_NAMELEN) 1074 return -EINVAL; 1075 1076 if (addr->can_addr.tp.tx_id & (CAN_ERR_FLAG | CAN_RTR_FLAG)) 1077 return -EADDRNOTAVAIL; 1078 1079 if (!addr->can_ifindex) 1080 return -ENODEV; 1081 1082 lock_sock(sk); 1083 1084 /* do not register frame reception for functional addressing */ 1085 if (so->opt.flags & CAN_ISOTP_SF_BROADCAST) 1086 do_rx_reg = 0; 1087 1088 /* do not validate rx address for functional addressing */ 1089 if (do_rx_reg) { 1090 if (addr->can_addr.tp.rx_id == addr->can_addr.tp.tx_id) { 1091 err = -EADDRNOTAVAIL; 1092 goto out; 1093 } 1094 1095 if (addr->can_addr.tp.rx_id & (CAN_ERR_FLAG | CAN_RTR_FLAG)) { 1096 err = -EADDRNOTAVAIL; 1097 goto out; 1098 } 1099 } 1100 1101 if (so->bound && addr->can_ifindex == so->ifindex && 1102 addr->can_addr.tp.rx_id == so->rxid && 1103 addr->can_addr.tp.tx_id == so->txid) 1104 goto out; 1105 1106 dev = dev_get_by_index(net, addr->can_ifindex); 1107 if (!dev) { 1108 err = -ENODEV; 1109 goto out; 1110 } 1111 if (dev->type != ARPHRD_CAN) { 1112 dev_put(dev); 1113 err = -ENODEV; 1114 goto out; 1115 } 1116 if (dev->mtu < so->ll.mtu) { 1117 dev_put(dev); 1118 err = -EINVAL; 1119 goto out; 1120 } 1121 if (!(dev->flags & IFF_UP)) 1122 notify_enetdown = 1; 1123 1124 ifindex = dev->ifindex; 1125 1126 if (do_rx_reg) 1127 can_rx_register(net, dev, addr->can_addr.tp.rx_id, 1128 SINGLE_MASK(addr->can_addr.tp.rx_id), 1129 isotp_rcv, sk, "isotp", sk); 1130 1131 dev_put(dev); 1132 1133 if (so->bound && do_rx_reg) { 1134 /* unregister old filter */ 1135 if (so->ifindex) { 1136 dev = dev_get_by_index(net, so->ifindex); 1137 if (dev) { 1138 can_rx_unregister(net, dev, so->rxid, 1139 SINGLE_MASK(so->rxid), 1140 isotp_rcv, sk); 1141 dev_put(dev); 1142 } 1143 } 1144 } 1145 1146 /* switch to new settings */ 1147 so->ifindex = ifindex; 1148 so->rxid = addr->can_addr.tp.rx_id; 1149 so->txid = addr->can_addr.tp.tx_id; 1150 so->bound = 1; 1151 1152 out: 1153 release_sock(sk); 1154 1155 if (notify_enetdown) { 1156 sk->sk_err = ENETDOWN; 1157 if (!sock_flag(sk, SOCK_DEAD)) 1158 sk->sk_error_report(sk); 1159 } 1160 1161 return err; 1162 } 1163 1164 static int isotp_getname(struct socket *sock, struct sockaddr *uaddr, int peer) 1165 { 1166 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; 1167 struct sock *sk = sock->sk; 1168 struct isotp_sock *so = isotp_sk(sk); 1169 1170 if (peer) 1171 return -EOPNOTSUPP; 1172 1173 memset(addr, 0, ISOTP_MIN_NAMELEN); 1174 addr->can_family = AF_CAN; 1175 addr->can_ifindex = so->ifindex; 1176 addr->can_addr.tp.rx_id = so->rxid; 1177 addr->can_addr.tp.tx_id = so->txid; 1178 1179 return ISOTP_MIN_NAMELEN; 1180 } 1181 1182 static int isotp_setsockopt_locked(struct socket *sock, int level, int optname, 1183 sockptr_t optval, unsigned int optlen) 1184 { 1185 struct sock *sk = sock->sk; 1186 struct isotp_sock *so = isotp_sk(sk); 1187 int ret = 0; 1188 1189 if (so->bound) 1190 return -EISCONN; 1191 1192 switch (optname) { 1193 case CAN_ISOTP_OPTS: 1194 if (optlen != sizeof(struct can_isotp_options)) 1195 return -EINVAL; 1196 1197 if (copy_from_sockptr(&so->opt, optval, optlen)) 1198 return -EFAULT; 1199 1200 /* no separate rx_ext_address is given => use ext_address */ 1201 if (!(so->opt.flags & CAN_ISOTP_RX_EXT_ADDR)) 1202 so->opt.rx_ext_address = so->opt.ext_address; 1203 break; 1204 1205 case CAN_ISOTP_RECV_FC: 1206 if (optlen != sizeof(struct can_isotp_fc_options)) 1207 return -EINVAL; 1208 1209 if (copy_from_sockptr(&so->rxfc, optval, optlen)) 1210 return -EFAULT; 1211 break; 1212 1213 case CAN_ISOTP_TX_STMIN: 1214 if (optlen != sizeof(u32)) 1215 return -EINVAL; 1216 1217 if (copy_from_sockptr(&so->force_tx_stmin, optval, optlen)) 1218 return -EFAULT; 1219 break; 1220 1221 case CAN_ISOTP_RX_STMIN: 1222 if (optlen != sizeof(u32)) 1223 return -EINVAL; 1224 1225 if (copy_from_sockptr(&so->force_rx_stmin, optval, optlen)) 1226 return -EFAULT; 1227 break; 1228 1229 case CAN_ISOTP_LL_OPTS: 1230 if (optlen == sizeof(struct can_isotp_ll_options)) { 1231 struct can_isotp_ll_options ll; 1232 1233 if (copy_from_sockptr(&ll, optval, optlen)) 1234 return -EFAULT; 1235 1236 /* check for correct ISO 11898-1 DLC data length */ 1237 if (ll.tx_dl != padlen(ll.tx_dl)) 1238 return -EINVAL; 1239 1240 if (ll.mtu != CAN_MTU && ll.mtu != CANFD_MTU) 1241 return -EINVAL; 1242 1243 if (ll.mtu == CAN_MTU && 1244 (ll.tx_dl > CAN_MAX_DLEN || ll.tx_flags != 0)) 1245 return -EINVAL; 1246 1247 memcpy(&so->ll, &ll, sizeof(ll)); 1248 1249 /* set ll_dl for tx path to similar place as for rx */ 1250 so->tx.ll_dl = ll.tx_dl; 1251 } else { 1252 return -EINVAL; 1253 } 1254 break; 1255 1256 default: 1257 ret = -ENOPROTOOPT; 1258 } 1259 1260 return ret; 1261 } 1262 1263 static int isotp_setsockopt(struct socket *sock, int level, int optname, 1264 sockptr_t optval, unsigned int optlen) 1265 1266 { 1267 struct sock *sk = sock->sk; 1268 int ret; 1269 1270 if (level != SOL_CAN_ISOTP) 1271 return -EINVAL; 1272 1273 lock_sock(sk); 1274 ret = isotp_setsockopt_locked(sock, level, optname, optval, optlen); 1275 release_sock(sk); 1276 return ret; 1277 } 1278 1279 static int isotp_getsockopt(struct socket *sock, int level, int optname, 1280 char __user *optval, int __user *optlen) 1281 { 1282 struct sock *sk = sock->sk; 1283 struct isotp_sock *so = isotp_sk(sk); 1284 int len; 1285 void *val; 1286 1287 if (level != SOL_CAN_ISOTP) 1288 return -EINVAL; 1289 if (get_user(len, optlen)) 1290 return -EFAULT; 1291 if (len < 0) 1292 return -EINVAL; 1293 1294 switch (optname) { 1295 case CAN_ISOTP_OPTS: 1296 len = min_t(int, len, sizeof(struct can_isotp_options)); 1297 val = &so->opt; 1298 break; 1299 1300 case CAN_ISOTP_RECV_FC: 1301 len = min_t(int, len, sizeof(struct can_isotp_fc_options)); 1302 val = &so->rxfc; 1303 break; 1304 1305 case CAN_ISOTP_TX_STMIN: 1306 len = min_t(int, len, sizeof(u32)); 1307 val = &so->force_tx_stmin; 1308 break; 1309 1310 case CAN_ISOTP_RX_STMIN: 1311 len = min_t(int, len, sizeof(u32)); 1312 val = &so->force_rx_stmin; 1313 break; 1314 1315 case CAN_ISOTP_LL_OPTS: 1316 len = min_t(int, len, sizeof(struct can_isotp_ll_options)); 1317 val = &so->ll; 1318 break; 1319 1320 default: 1321 return -ENOPROTOOPT; 1322 } 1323 1324 if (put_user(len, optlen)) 1325 return -EFAULT; 1326 if (copy_to_user(optval, val, len)) 1327 return -EFAULT; 1328 return 0; 1329 } 1330 1331 static void isotp_notify(struct isotp_sock *so, unsigned long msg, 1332 struct net_device *dev) 1333 { 1334 struct sock *sk = &so->sk; 1335 1336 if (!net_eq(dev_net(dev), sock_net(sk))) 1337 return; 1338 1339 if (so->ifindex != dev->ifindex) 1340 return; 1341 1342 switch (msg) { 1343 case NETDEV_UNREGISTER: 1344 lock_sock(sk); 1345 /* remove current filters & unregister */ 1346 if (so->bound && (!(so->opt.flags & CAN_ISOTP_SF_BROADCAST))) 1347 can_rx_unregister(dev_net(dev), dev, so->rxid, 1348 SINGLE_MASK(so->rxid), 1349 isotp_rcv, sk); 1350 1351 so->ifindex = 0; 1352 so->bound = 0; 1353 release_sock(sk); 1354 1355 sk->sk_err = ENODEV; 1356 if (!sock_flag(sk, SOCK_DEAD)) 1357 sk->sk_error_report(sk); 1358 break; 1359 1360 case NETDEV_DOWN: 1361 sk->sk_err = ENETDOWN; 1362 if (!sock_flag(sk, SOCK_DEAD)) 1363 sk->sk_error_report(sk); 1364 break; 1365 } 1366 } 1367 1368 static int isotp_notifier(struct notifier_block *nb, unsigned long msg, 1369 void *ptr) 1370 { 1371 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 1372 1373 if (dev->type != ARPHRD_CAN) 1374 return NOTIFY_DONE; 1375 if (msg != NETDEV_UNREGISTER && msg != NETDEV_DOWN) 1376 return NOTIFY_DONE; 1377 if (unlikely(isotp_busy_notifier)) /* Check for reentrant bug. */ 1378 return NOTIFY_DONE; 1379 1380 spin_lock(&isotp_notifier_lock); 1381 list_for_each_entry(isotp_busy_notifier, &isotp_notifier_list, notifier) { 1382 spin_unlock(&isotp_notifier_lock); 1383 isotp_notify(isotp_busy_notifier, msg, dev); 1384 spin_lock(&isotp_notifier_lock); 1385 } 1386 isotp_busy_notifier = NULL; 1387 spin_unlock(&isotp_notifier_lock); 1388 return NOTIFY_DONE; 1389 } 1390 1391 static int isotp_init(struct sock *sk) 1392 { 1393 struct isotp_sock *so = isotp_sk(sk); 1394 1395 so->ifindex = 0; 1396 so->bound = 0; 1397 1398 so->opt.flags = CAN_ISOTP_DEFAULT_FLAGS; 1399 so->opt.ext_address = CAN_ISOTP_DEFAULT_EXT_ADDRESS; 1400 so->opt.rx_ext_address = CAN_ISOTP_DEFAULT_EXT_ADDRESS; 1401 so->opt.rxpad_content = CAN_ISOTP_DEFAULT_PAD_CONTENT; 1402 so->opt.txpad_content = CAN_ISOTP_DEFAULT_PAD_CONTENT; 1403 so->opt.frame_txtime = CAN_ISOTP_DEFAULT_FRAME_TXTIME; 1404 so->rxfc.bs = CAN_ISOTP_DEFAULT_RECV_BS; 1405 so->rxfc.stmin = CAN_ISOTP_DEFAULT_RECV_STMIN; 1406 so->rxfc.wftmax = CAN_ISOTP_DEFAULT_RECV_WFTMAX; 1407 so->ll.mtu = CAN_ISOTP_DEFAULT_LL_MTU; 1408 so->ll.tx_dl = CAN_ISOTP_DEFAULT_LL_TX_DL; 1409 so->ll.tx_flags = CAN_ISOTP_DEFAULT_LL_TX_FLAGS; 1410 1411 /* set ll_dl for tx path to similar place as for rx */ 1412 so->tx.ll_dl = so->ll.tx_dl; 1413 1414 so->rx.state = ISOTP_IDLE; 1415 so->tx.state = ISOTP_IDLE; 1416 1417 hrtimer_init(&so->rxtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT); 1418 so->rxtimer.function = isotp_rx_timer_handler; 1419 hrtimer_init(&so->txtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT); 1420 so->txtimer.function = isotp_tx_timer_handler; 1421 1422 init_waitqueue_head(&so->wait); 1423 1424 spin_lock(&isotp_notifier_lock); 1425 list_add_tail(&so->notifier, &isotp_notifier_list); 1426 spin_unlock(&isotp_notifier_lock); 1427 1428 return 0; 1429 } 1430 1431 static int isotp_sock_no_ioctlcmd(struct socket *sock, unsigned int cmd, 1432 unsigned long arg) 1433 { 1434 /* no ioctls for socket layer -> hand it down to NIC layer */ 1435 return -ENOIOCTLCMD; 1436 } 1437 1438 static const struct proto_ops isotp_ops = { 1439 .family = PF_CAN, 1440 .release = isotp_release, 1441 .bind = isotp_bind, 1442 .connect = sock_no_connect, 1443 .socketpair = sock_no_socketpair, 1444 .accept = sock_no_accept, 1445 .getname = isotp_getname, 1446 .poll = datagram_poll, 1447 .ioctl = isotp_sock_no_ioctlcmd, 1448 .gettstamp = sock_gettstamp, 1449 .listen = sock_no_listen, 1450 .shutdown = sock_no_shutdown, 1451 .setsockopt = isotp_setsockopt, 1452 .getsockopt = isotp_getsockopt, 1453 .sendmsg = isotp_sendmsg, 1454 .recvmsg = isotp_recvmsg, 1455 .mmap = sock_no_mmap, 1456 .sendpage = sock_no_sendpage, 1457 }; 1458 1459 static struct proto isotp_proto __read_mostly = { 1460 .name = "CAN_ISOTP", 1461 .owner = THIS_MODULE, 1462 .obj_size = sizeof(struct isotp_sock), 1463 .init = isotp_init, 1464 }; 1465 1466 static const struct can_proto isotp_can_proto = { 1467 .type = SOCK_DGRAM, 1468 .protocol = CAN_ISOTP, 1469 .ops = &isotp_ops, 1470 .prot = &isotp_proto, 1471 }; 1472 1473 static struct notifier_block canisotp_notifier = { 1474 .notifier_call = isotp_notifier 1475 }; 1476 1477 static __init int isotp_module_init(void) 1478 { 1479 int err; 1480 1481 pr_info("can: isotp protocol\n"); 1482 1483 err = can_proto_register(&isotp_can_proto); 1484 if (err < 0) 1485 pr_err("can: registration of isotp protocol failed\n"); 1486 else 1487 register_netdevice_notifier(&canisotp_notifier); 1488 1489 return err; 1490 } 1491 1492 static __exit void isotp_module_exit(void) 1493 { 1494 can_proto_unregister(&isotp_can_proto); 1495 unregister_netdevice_notifier(&canisotp_notifier); 1496 } 1497 1498 module_init(isotp_module_init); 1499 module_exit(isotp_module_exit); 1500