1 /* 2 * bcm.c - Broadcast Manager to filter/send (cyclic) CAN content 3 * 4 * Copyright (c) 2002-2007 Volkswagen Group Electronic Research 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of Volkswagen nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * Alternatively, provided that this notice is retained in full, this 20 * software may be distributed under the terms of the GNU General 21 * Public License ("GPL") version 2, in which case the provisions of the 22 * GPL apply INSTEAD OF those given above. 23 * 24 * The provided data structures and external interfaces from this code 25 * are not restricted to be used by modules with a GPL compatible license. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 28 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 29 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 30 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 31 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 32 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 33 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 34 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 35 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 36 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 37 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH 38 * DAMAGE. 39 * 40 * Send feedback to <socketcan-users@lists.berlios.de> 41 * 42 */ 43 44 #include <linux/module.h> 45 #include <linux/init.h> 46 #include <linux/hrtimer.h> 47 #include <linux/list.h> 48 #include <linux/proc_fs.h> 49 #include <linux/seq_file.h> 50 #include <linux/uio.h> 51 #include <linux/net.h> 52 #include <linux/netdevice.h> 53 #include <linux/socket.h> 54 #include <linux/if_arp.h> 55 #include <linux/skbuff.h> 56 #include <linux/can.h> 57 #include <linux/can/core.h> 58 #include <linux/can/bcm.h> 59 #include <linux/slab.h> 60 #include <net/sock.h> 61 #include <net/net_namespace.h> 62 63 /* 64 * To send multiple CAN frame content within TX_SETUP or to filter 65 * CAN messages with multiplex index within RX_SETUP, the number of 66 * different filters is limited to 256 due to the one byte index value. 67 */ 68 #define MAX_NFRAMES 256 69 70 /* use of last_frames[index].can_dlc */ 71 #define RX_RECV 0x40 /* received data for this element */ 72 #define RX_THR 0x80 /* element not been sent due to throttle feature */ 73 #define BCM_CAN_DLC_MASK 0x0F /* clean private flags in can_dlc by masking */ 74 75 /* get best masking value for can_rx_register() for a given single can_id */ 76 #define REGMASK(id) ((id & CAN_EFF_FLAG) ? \ 77 (CAN_EFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG) : \ 78 (CAN_SFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG)) 79 80 #define CAN_BCM_VERSION CAN_VERSION 81 static __initdata const char banner[] = KERN_INFO 82 "can: broadcast manager protocol (rev " CAN_BCM_VERSION " t)\n"; 83 84 MODULE_DESCRIPTION("PF_CAN broadcast manager protocol"); 85 MODULE_LICENSE("Dual BSD/GPL"); 86 MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>"); 87 MODULE_ALIAS("can-proto-2"); 88 89 /* easy access to can_frame payload */ 90 static inline u64 GET_U64(const struct can_frame *cp) 91 { 92 return *(u64 *)cp->data; 93 } 94 95 struct bcm_op { 96 struct list_head list; 97 int ifindex; 98 canid_t can_id; 99 u32 flags; 100 unsigned long frames_abs, frames_filtered; 101 struct timeval ival1, ival2; 102 struct hrtimer timer, thrtimer; 103 struct tasklet_struct tsklet, thrtsklet; 104 ktime_t rx_stamp, kt_ival1, kt_ival2, kt_lastmsg; 105 int rx_ifindex; 106 u32 count; 107 u32 nframes; 108 u32 currframe; 109 struct can_frame *frames; 110 struct can_frame *last_frames; 111 struct can_frame sframe; 112 struct can_frame last_sframe; 113 struct sock *sk; 114 struct net_device *rx_reg_dev; 115 }; 116 117 static struct proc_dir_entry *proc_dir; 118 119 struct bcm_sock { 120 struct sock sk; 121 int bound; 122 int ifindex; 123 struct notifier_block notifier; 124 struct list_head rx_ops; 125 struct list_head tx_ops; 126 unsigned long dropped_usr_msgs; 127 struct proc_dir_entry *bcm_proc_read; 128 char procname [32]; /* inode number in decimal with \0 */ 129 }; 130 131 static inline struct bcm_sock *bcm_sk(const struct sock *sk) 132 { 133 return (struct bcm_sock *)sk; 134 } 135 136 #define CFSIZ sizeof(struct can_frame) 137 #define OPSIZ sizeof(struct bcm_op) 138 #define MHSIZ sizeof(struct bcm_msg_head) 139 140 /* 141 * procfs functions 142 */ 143 static char *bcm_proc_getifname(char *result, int ifindex) 144 { 145 struct net_device *dev; 146 147 if (!ifindex) 148 return "any"; 149 150 rcu_read_lock(); 151 dev = dev_get_by_index_rcu(&init_net, ifindex); 152 if (dev) 153 strcpy(result, dev->name); 154 else 155 strcpy(result, "???"); 156 rcu_read_unlock(); 157 158 return result; 159 } 160 161 static int bcm_proc_show(struct seq_file *m, void *v) 162 { 163 char ifname[IFNAMSIZ]; 164 struct sock *sk = (struct sock *)m->private; 165 struct bcm_sock *bo = bcm_sk(sk); 166 struct bcm_op *op; 167 168 seq_printf(m, ">>> socket %pK", sk->sk_socket); 169 seq_printf(m, " / sk %pK", sk); 170 seq_printf(m, " / bo %pK", bo); 171 seq_printf(m, " / dropped %lu", bo->dropped_usr_msgs); 172 seq_printf(m, " / bound %s", bcm_proc_getifname(ifname, bo->ifindex)); 173 seq_printf(m, " <<<\n"); 174 175 list_for_each_entry(op, &bo->rx_ops, list) { 176 177 unsigned long reduction; 178 179 /* print only active entries & prevent division by zero */ 180 if (!op->frames_abs) 181 continue; 182 183 seq_printf(m, "rx_op: %03X %-5s ", 184 op->can_id, bcm_proc_getifname(ifname, op->ifindex)); 185 seq_printf(m, "[%u]%c ", op->nframes, 186 (op->flags & RX_CHECK_DLC)?'d':' '); 187 if (op->kt_ival1.tv64) 188 seq_printf(m, "timeo=%lld ", 189 (long long) 190 ktime_to_us(op->kt_ival1)); 191 192 if (op->kt_ival2.tv64) 193 seq_printf(m, "thr=%lld ", 194 (long long) 195 ktime_to_us(op->kt_ival2)); 196 197 seq_printf(m, "# recv %ld (%ld) => reduction: ", 198 op->frames_filtered, op->frames_abs); 199 200 reduction = 100 - (op->frames_filtered * 100) / op->frames_abs; 201 202 seq_printf(m, "%s%ld%%\n", 203 (reduction == 100)?"near ":"", reduction); 204 } 205 206 list_for_each_entry(op, &bo->tx_ops, list) { 207 208 seq_printf(m, "tx_op: %03X %s [%u] ", 209 op->can_id, 210 bcm_proc_getifname(ifname, op->ifindex), 211 op->nframes); 212 213 if (op->kt_ival1.tv64) 214 seq_printf(m, "t1=%lld ", 215 (long long) ktime_to_us(op->kt_ival1)); 216 217 if (op->kt_ival2.tv64) 218 seq_printf(m, "t2=%lld ", 219 (long long) ktime_to_us(op->kt_ival2)); 220 221 seq_printf(m, "# sent %ld\n", op->frames_abs); 222 } 223 seq_putc(m, '\n'); 224 return 0; 225 } 226 227 static int bcm_proc_open(struct inode *inode, struct file *file) 228 { 229 return single_open(file, bcm_proc_show, PDE(inode)->data); 230 } 231 232 static const struct file_operations bcm_proc_fops = { 233 .owner = THIS_MODULE, 234 .open = bcm_proc_open, 235 .read = seq_read, 236 .llseek = seq_lseek, 237 .release = single_release, 238 }; 239 240 /* 241 * bcm_can_tx - send the (next) CAN frame to the appropriate CAN interface 242 * of the given bcm tx op 243 */ 244 static void bcm_can_tx(struct bcm_op *op) 245 { 246 struct sk_buff *skb; 247 struct net_device *dev; 248 struct can_frame *cf = &op->frames[op->currframe]; 249 250 /* no target device? => exit */ 251 if (!op->ifindex) 252 return; 253 254 dev = dev_get_by_index(&init_net, op->ifindex); 255 if (!dev) { 256 /* RFC: should this bcm_op remove itself here? */ 257 return; 258 } 259 260 skb = alloc_skb(CFSIZ, gfp_any()); 261 if (!skb) 262 goto out; 263 264 memcpy(skb_put(skb, CFSIZ), cf, CFSIZ); 265 266 /* send with loopback */ 267 skb->dev = dev; 268 skb->sk = op->sk; 269 can_send(skb, 1); 270 271 /* update statistics */ 272 op->currframe++; 273 op->frames_abs++; 274 275 /* reached last frame? */ 276 if (op->currframe >= op->nframes) 277 op->currframe = 0; 278 out: 279 dev_put(dev); 280 } 281 282 /* 283 * bcm_send_to_user - send a BCM message to the userspace 284 * (consisting of bcm_msg_head + x CAN frames) 285 */ 286 static void bcm_send_to_user(struct bcm_op *op, struct bcm_msg_head *head, 287 struct can_frame *frames, int has_timestamp) 288 { 289 struct sk_buff *skb; 290 struct can_frame *firstframe; 291 struct sockaddr_can *addr; 292 struct sock *sk = op->sk; 293 unsigned int datalen = head->nframes * CFSIZ; 294 int err; 295 296 skb = alloc_skb(sizeof(*head) + datalen, gfp_any()); 297 if (!skb) 298 return; 299 300 memcpy(skb_put(skb, sizeof(*head)), head, sizeof(*head)); 301 302 if (head->nframes) { 303 /* can_frames starting here */ 304 firstframe = (struct can_frame *)skb_tail_pointer(skb); 305 306 memcpy(skb_put(skb, datalen), frames, datalen); 307 308 /* 309 * the BCM uses the can_dlc-element of the can_frame 310 * structure for internal purposes. This is only 311 * relevant for updates that are generated by the 312 * BCM, where nframes is 1 313 */ 314 if (head->nframes == 1) 315 firstframe->can_dlc &= BCM_CAN_DLC_MASK; 316 } 317 318 if (has_timestamp) { 319 /* restore rx timestamp */ 320 skb->tstamp = op->rx_stamp; 321 } 322 323 /* 324 * Put the datagram to the queue so that bcm_recvmsg() can 325 * get it from there. We need to pass the interface index to 326 * bcm_recvmsg(). We pass a whole struct sockaddr_can in skb->cb 327 * containing the interface index. 328 */ 329 330 BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct sockaddr_can)); 331 addr = (struct sockaddr_can *)skb->cb; 332 memset(addr, 0, sizeof(*addr)); 333 addr->can_family = AF_CAN; 334 addr->can_ifindex = op->rx_ifindex; 335 336 err = sock_queue_rcv_skb(sk, skb); 337 if (err < 0) { 338 struct bcm_sock *bo = bcm_sk(sk); 339 340 kfree_skb(skb); 341 /* don't care about overflows in this statistic */ 342 bo->dropped_usr_msgs++; 343 } 344 } 345 346 static void bcm_tx_timeout_tsklet(unsigned long data) 347 { 348 struct bcm_op *op = (struct bcm_op *)data; 349 struct bcm_msg_head msg_head; 350 351 if (op->kt_ival1.tv64 && (op->count > 0)) { 352 353 op->count--; 354 if (!op->count && (op->flags & TX_COUNTEVT)) { 355 356 /* create notification to user */ 357 msg_head.opcode = TX_EXPIRED; 358 msg_head.flags = op->flags; 359 msg_head.count = op->count; 360 msg_head.ival1 = op->ival1; 361 msg_head.ival2 = op->ival2; 362 msg_head.can_id = op->can_id; 363 msg_head.nframes = 0; 364 365 bcm_send_to_user(op, &msg_head, NULL, 0); 366 } 367 } 368 369 if (op->kt_ival1.tv64 && (op->count > 0)) { 370 371 /* send (next) frame */ 372 bcm_can_tx(op); 373 hrtimer_start(&op->timer, 374 ktime_add(ktime_get(), op->kt_ival1), 375 HRTIMER_MODE_ABS); 376 377 } else { 378 if (op->kt_ival2.tv64) { 379 380 /* send (next) frame */ 381 bcm_can_tx(op); 382 hrtimer_start(&op->timer, 383 ktime_add(ktime_get(), op->kt_ival2), 384 HRTIMER_MODE_ABS); 385 } 386 } 387 } 388 389 /* 390 * bcm_tx_timeout_handler - performs cyclic CAN frame transmissions 391 */ 392 static enum hrtimer_restart bcm_tx_timeout_handler(struct hrtimer *hrtimer) 393 { 394 struct bcm_op *op = container_of(hrtimer, struct bcm_op, timer); 395 396 tasklet_schedule(&op->tsklet); 397 398 return HRTIMER_NORESTART; 399 } 400 401 /* 402 * bcm_rx_changed - create a RX_CHANGED notification due to changed content 403 */ 404 static void bcm_rx_changed(struct bcm_op *op, struct can_frame *data) 405 { 406 struct bcm_msg_head head; 407 408 /* update statistics */ 409 op->frames_filtered++; 410 411 /* prevent statistics overflow */ 412 if (op->frames_filtered > ULONG_MAX/100) 413 op->frames_filtered = op->frames_abs = 0; 414 415 /* this element is not throttled anymore */ 416 data->can_dlc &= (BCM_CAN_DLC_MASK|RX_RECV); 417 418 head.opcode = RX_CHANGED; 419 head.flags = op->flags; 420 head.count = op->count; 421 head.ival1 = op->ival1; 422 head.ival2 = op->ival2; 423 head.can_id = op->can_id; 424 head.nframes = 1; 425 426 bcm_send_to_user(op, &head, data, 1); 427 } 428 429 /* 430 * bcm_rx_update_and_send - process a detected relevant receive content change 431 * 1. update the last received data 432 * 2. send a notification to the user (if possible) 433 */ 434 static void bcm_rx_update_and_send(struct bcm_op *op, 435 struct can_frame *lastdata, 436 const struct can_frame *rxdata) 437 { 438 memcpy(lastdata, rxdata, CFSIZ); 439 440 /* mark as used and throttled by default */ 441 lastdata->can_dlc |= (RX_RECV|RX_THR); 442 443 /* throtteling mode inactive ? */ 444 if (!op->kt_ival2.tv64) { 445 /* send RX_CHANGED to the user immediately */ 446 bcm_rx_changed(op, lastdata); 447 return; 448 } 449 450 /* with active throttling timer we are just done here */ 451 if (hrtimer_active(&op->thrtimer)) 452 return; 453 454 /* first receiption with enabled throttling mode */ 455 if (!op->kt_lastmsg.tv64) 456 goto rx_changed_settime; 457 458 /* got a second frame inside a potential throttle period? */ 459 if (ktime_us_delta(ktime_get(), op->kt_lastmsg) < 460 ktime_to_us(op->kt_ival2)) { 461 /* do not send the saved data - only start throttle timer */ 462 hrtimer_start(&op->thrtimer, 463 ktime_add(op->kt_lastmsg, op->kt_ival2), 464 HRTIMER_MODE_ABS); 465 return; 466 } 467 468 /* the gap was that big, that throttling was not needed here */ 469 rx_changed_settime: 470 bcm_rx_changed(op, lastdata); 471 op->kt_lastmsg = ktime_get(); 472 } 473 474 /* 475 * bcm_rx_cmp_to_index - (bit)compares the currently received data to formerly 476 * received data stored in op->last_frames[] 477 */ 478 static void bcm_rx_cmp_to_index(struct bcm_op *op, unsigned int index, 479 const struct can_frame *rxdata) 480 { 481 /* 482 * no one uses the MSBs of can_dlc for comparation, 483 * so we use it here to detect the first time of reception 484 */ 485 486 if (!(op->last_frames[index].can_dlc & RX_RECV)) { 487 /* received data for the first time => send update to user */ 488 bcm_rx_update_and_send(op, &op->last_frames[index], rxdata); 489 return; 490 } 491 492 /* do a real check in can_frame data section */ 493 494 if ((GET_U64(&op->frames[index]) & GET_U64(rxdata)) != 495 (GET_U64(&op->frames[index]) & GET_U64(&op->last_frames[index]))) { 496 bcm_rx_update_and_send(op, &op->last_frames[index], rxdata); 497 return; 498 } 499 500 if (op->flags & RX_CHECK_DLC) { 501 /* do a real check in can_frame dlc */ 502 if (rxdata->can_dlc != (op->last_frames[index].can_dlc & 503 BCM_CAN_DLC_MASK)) { 504 bcm_rx_update_and_send(op, &op->last_frames[index], 505 rxdata); 506 return; 507 } 508 } 509 } 510 511 /* 512 * bcm_rx_starttimer - enable timeout monitoring for CAN frame receiption 513 */ 514 static void bcm_rx_starttimer(struct bcm_op *op) 515 { 516 if (op->flags & RX_NO_AUTOTIMER) 517 return; 518 519 if (op->kt_ival1.tv64) 520 hrtimer_start(&op->timer, op->kt_ival1, HRTIMER_MODE_REL); 521 } 522 523 static void bcm_rx_timeout_tsklet(unsigned long data) 524 { 525 struct bcm_op *op = (struct bcm_op *)data; 526 struct bcm_msg_head msg_head; 527 528 /* create notification to user */ 529 msg_head.opcode = RX_TIMEOUT; 530 msg_head.flags = op->flags; 531 msg_head.count = op->count; 532 msg_head.ival1 = op->ival1; 533 msg_head.ival2 = op->ival2; 534 msg_head.can_id = op->can_id; 535 msg_head.nframes = 0; 536 537 bcm_send_to_user(op, &msg_head, NULL, 0); 538 } 539 540 /* 541 * bcm_rx_timeout_handler - when the (cyclic) CAN frame receiption timed out 542 */ 543 static enum hrtimer_restart bcm_rx_timeout_handler(struct hrtimer *hrtimer) 544 { 545 struct bcm_op *op = container_of(hrtimer, struct bcm_op, timer); 546 547 /* schedule before NET_RX_SOFTIRQ */ 548 tasklet_hi_schedule(&op->tsklet); 549 550 /* no restart of the timer is done here! */ 551 552 /* if user wants to be informed, when cyclic CAN-Messages come back */ 553 if ((op->flags & RX_ANNOUNCE_RESUME) && op->last_frames) { 554 /* clear received can_frames to indicate 'nothing received' */ 555 memset(op->last_frames, 0, op->nframes * CFSIZ); 556 } 557 558 return HRTIMER_NORESTART; 559 } 560 561 /* 562 * bcm_rx_do_flush - helper for bcm_rx_thr_flush 563 */ 564 static inline int bcm_rx_do_flush(struct bcm_op *op, int update, 565 unsigned int index) 566 { 567 if ((op->last_frames) && (op->last_frames[index].can_dlc & RX_THR)) { 568 if (update) 569 bcm_rx_changed(op, &op->last_frames[index]); 570 return 1; 571 } 572 return 0; 573 } 574 575 /* 576 * bcm_rx_thr_flush - Check for throttled data and send it to the userspace 577 * 578 * update == 0 : just check if throttled data is available (any irq context) 579 * update == 1 : check and send throttled data to userspace (soft_irq context) 580 */ 581 static int bcm_rx_thr_flush(struct bcm_op *op, int update) 582 { 583 int updated = 0; 584 585 if (op->nframes > 1) { 586 unsigned int i; 587 588 /* for MUX filter we start at index 1 */ 589 for (i = 1; i < op->nframes; i++) 590 updated += bcm_rx_do_flush(op, update, i); 591 592 } else { 593 /* for RX_FILTER_ID and simple filter */ 594 updated += bcm_rx_do_flush(op, update, 0); 595 } 596 597 return updated; 598 } 599 600 static void bcm_rx_thr_tsklet(unsigned long data) 601 { 602 struct bcm_op *op = (struct bcm_op *)data; 603 604 /* push the changed data to the userspace */ 605 bcm_rx_thr_flush(op, 1); 606 } 607 608 /* 609 * bcm_rx_thr_handler - the time for blocked content updates is over now: 610 * Check for throttled data and send it to the userspace 611 */ 612 static enum hrtimer_restart bcm_rx_thr_handler(struct hrtimer *hrtimer) 613 { 614 struct bcm_op *op = container_of(hrtimer, struct bcm_op, thrtimer); 615 616 tasklet_schedule(&op->thrtsklet); 617 618 if (bcm_rx_thr_flush(op, 0)) { 619 hrtimer_forward(hrtimer, ktime_get(), op->kt_ival2); 620 return HRTIMER_RESTART; 621 } else { 622 /* rearm throttle handling */ 623 op->kt_lastmsg = ktime_set(0, 0); 624 return HRTIMER_NORESTART; 625 } 626 } 627 628 /* 629 * bcm_rx_handler - handle a CAN frame receiption 630 */ 631 static void bcm_rx_handler(struct sk_buff *skb, void *data) 632 { 633 struct bcm_op *op = (struct bcm_op *)data; 634 const struct can_frame *rxframe = (struct can_frame *)skb->data; 635 unsigned int i; 636 637 /* disable timeout */ 638 hrtimer_cancel(&op->timer); 639 640 if (op->can_id != rxframe->can_id) 641 return; 642 643 /* save rx timestamp */ 644 op->rx_stamp = skb->tstamp; 645 /* save originator for recvfrom() */ 646 op->rx_ifindex = skb->dev->ifindex; 647 /* update statistics */ 648 op->frames_abs++; 649 650 if (op->flags & RX_RTR_FRAME) { 651 /* send reply for RTR-request (placed in op->frames[0]) */ 652 bcm_can_tx(op); 653 return; 654 } 655 656 if (op->flags & RX_FILTER_ID) { 657 /* the easiest case */ 658 bcm_rx_update_and_send(op, &op->last_frames[0], rxframe); 659 goto rx_starttimer; 660 } 661 662 if (op->nframes == 1) { 663 /* simple compare with index 0 */ 664 bcm_rx_cmp_to_index(op, 0, rxframe); 665 goto rx_starttimer; 666 } 667 668 if (op->nframes > 1) { 669 /* 670 * multiplex compare 671 * 672 * find the first multiplex mask that fits. 673 * Remark: The MUX-mask is stored in index 0 674 */ 675 676 for (i = 1; i < op->nframes; i++) { 677 if ((GET_U64(&op->frames[0]) & GET_U64(rxframe)) == 678 (GET_U64(&op->frames[0]) & 679 GET_U64(&op->frames[i]))) { 680 bcm_rx_cmp_to_index(op, i, rxframe); 681 break; 682 } 683 } 684 } 685 686 rx_starttimer: 687 bcm_rx_starttimer(op); 688 } 689 690 /* 691 * helpers for bcm_op handling: find & delete bcm [rx|tx] op elements 692 */ 693 static struct bcm_op *bcm_find_op(struct list_head *ops, canid_t can_id, 694 int ifindex) 695 { 696 struct bcm_op *op; 697 698 list_for_each_entry(op, ops, list) { 699 if ((op->can_id == can_id) && (op->ifindex == ifindex)) 700 return op; 701 } 702 703 return NULL; 704 } 705 706 static void bcm_remove_op(struct bcm_op *op) 707 { 708 hrtimer_cancel(&op->timer); 709 hrtimer_cancel(&op->thrtimer); 710 711 if (op->tsklet.func) 712 tasklet_kill(&op->tsklet); 713 714 if (op->thrtsklet.func) 715 tasklet_kill(&op->thrtsklet); 716 717 if ((op->frames) && (op->frames != &op->sframe)) 718 kfree(op->frames); 719 720 if ((op->last_frames) && (op->last_frames != &op->last_sframe)) 721 kfree(op->last_frames); 722 723 kfree(op); 724 } 725 726 static void bcm_rx_unreg(struct net_device *dev, struct bcm_op *op) 727 { 728 if (op->rx_reg_dev == dev) { 729 can_rx_unregister(dev, op->can_id, REGMASK(op->can_id), 730 bcm_rx_handler, op); 731 732 /* mark as removed subscription */ 733 op->rx_reg_dev = NULL; 734 } else 735 printk(KERN_ERR "can-bcm: bcm_rx_unreg: registered device " 736 "mismatch %p %p\n", op->rx_reg_dev, dev); 737 } 738 739 /* 740 * bcm_delete_rx_op - find and remove a rx op (returns number of removed ops) 741 */ 742 static int bcm_delete_rx_op(struct list_head *ops, canid_t can_id, int ifindex) 743 { 744 struct bcm_op *op, *n; 745 746 list_for_each_entry_safe(op, n, ops, list) { 747 if ((op->can_id == can_id) && (op->ifindex == ifindex)) { 748 749 /* 750 * Don't care if we're bound or not (due to netdev 751 * problems) can_rx_unregister() is always a save 752 * thing to do here. 753 */ 754 if (op->ifindex) { 755 /* 756 * Only remove subscriptions that had not 757 * been removed due to NETDEV_UNREGISTER 758 * in bcm_notifier() 759 */ 760 if (op->rx_reg_dev) { 761 struct net_device *dev; 762 763 dev = dev_get_by_index(&init_net, 764 op->ifindex); 765 if (dev) { 766 bcm_rx_unreg(dev, op); 767 dev_put(dev); 768 } 769 } 770 } else 771 can_rx_unregister(NULL, op->can_id, 772 REGMASK(op->can_id), 773 bcm_rx_handler, op); 774 775 list_del(&op->list); 776 bcm_remove_op(op); 777 return 1; /* done */ 778 } 779 } 780 781 return 0; /* not found */ 782 } 783 784 /* 785 * bcm_delete_tx_op - find and remove a tx op (returns number of removed ops) 786 */ 787 static int bcm_delete_tx_op(struct list_head *ops, canid_t can_id, int ifindex) 788 { 789 struct bcm_op *op, *n; 790 791 list_for_each_entry_safe(op, n, ops, list) { 792 if ((op->can_id == can_id) && (op->ifindex == ifindex)) { 793 list_del(&op->list); 794 bcm_remove_op(op); 795 return 1; /* done */ 796 } 797 } 798 799 return 0; /* not found */ 800 } 801 802 /* 803 * bcm_read_op - read out a bcm_op and send it to the user (for bcm_sendmsg) 804 */ 805 static int bcm_read_op(struct list_head *ops, struct bcm_msg_head *msg_head, 806 int ifindex) 807 { 808 struct bcm_op *op = bcm_find_op(ops, msg_head->can_id, ifindex); 809 810 if (!op) 811 return -EINVAL; 812 813 /* put current values into msg_head */ 814 msg_head->flags = op->flags; 815 msg_head->count = op->count; 816 msg_head->ival1 = op->ival1; 817 msg_head->ival2 = op->ival2; 818 msg_head->nframes = op->nframes; 819 820 bcm_send_to_user(op, msg_head, op->frames, 0); 821 822 return MHSIZ; 823 } 824 825 /* 826 * bcm_tx_setup - create or update a bcm tx op (for bcm_sendmsg) 827 */ 828 static int bcm_tx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg, 829 int ifindex, struct sock *sk) 830 { 831 struct bcm_sock *bo = bcm_sk(sk); 832 struct bcm_op *op; 833 unsigned int i; 834 int err; 835 836 /* we need a real device to send frames */ 837 if (!ifindex) 838 return -ENODEV; 839 840 /* check nframes boundaries - we need at least one can_frame */ 841 if (msg_head->nframes < 1 || msg_head->nframes > MAX_NFRAMES) 842 return -EINVAL; 843 844 /* check the given can_id */ 845 op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex); 846 847 if (op) { 848 /* update existing BCM operation */ 849 850 /* 851 * Do we need more space for the can_frames than currently 852 * allocated? -> This is a _really_ unusual use-case and 853 * therefore (complexity / locking) it is not supported. 854 */ 855 if (msg_head->nframes > op->nframes) 856 return -E2BIG; 857 858 /* update can_frames content */ 859 for (i = 0; i < msg_head->nframes; i++) { 860 err = memcpy_fromiovec((u8 *)&op->frames[i], 861 msg->msg_iov, CFSIZ); 862 863 if (op->frames[i].can_dlc > 8) 864 err = -EINVAL; 865 866 if (err < 0) 867 return err; 868 869 if (msg_head->flags & TX_CP_CAN_ID) { 870 /* copy can_id into frame */ 871 op->frames[i].can_id = msg_head->can_id; 872 } 873 } 874 875 } else { 876 /* insert new BCM operation for the given can_id */ 877 878 op = kzalloc(OPSIZ, GFP_KERNEL); 879 if (!op) 880 return -ENOMEM; 881 882 op->can_id = msg_head->can_id; 883 884 /* create array for can_frames and copy the data */ 885 if (msg_head->nframes > 1) { 886 op->frames = kmalloc(msg_head->nframes * CFSIZ, 887 GFP_KERNEL); 888 if (!op->frames) { 889 kfree(op); 890 return -ENOMEM; 891 } 892 } else 893 op->frames = &op->sframe; 894 895 for (i = 0; i < msg_head->nframes; i++) { 896 err = memcpy_fromiovec((u8 *)&op->frames[i], 897 msg->msg_iov, CFSIZ); 898 899 if (op->frames[i].can_dlc > 8) 900 err = -EINVAL; 901 902 if (err < 0) { 903 if (op->frames != &op->sframe) 904 kfree(op->frames); 905 kfree(op); 906 return err; 907 } 908 909 if (msg_head->flags & TX_CP_CAN_ID) { 910 /* copy can_id into frame */ 911 op->frames[i].can_id = msg_head->can_id; 912 } 913 } 914 915 /* tx_ops never compare with previous received messages */ 916 op->last_frames = NULL; 917 918 /* bcm_can_tx / bcm_tx_timeout_handler needs this */ 919 op->sk = sk; 920 op->ifindex = ifindex; 921 922 /* initialize uninitialized (kzalloc) structure */ 923 hrtimer_init(&op->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); 924 op->timer.function = bcm_tx_timeout_handler; 925 926 /* initialize tasklet for tx countevent notification */ 927 tasklet_init(&op->tsklet, bcm_tx_timeout_tsklet, 928 (unsigned long) op); 929 930 /* currently unused in tx_ops */ 931 hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); 932 933 /* add this bcm_op to the list of the tx_ops */ 934 list_add(&op->list, &bo->tx_ops); 935 936 } /* if ((op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex))) */ 937 938 if (op->nframes != msg_head->nframes) { 939 op->nframes = msg_head->nframes; 940 /* start multiple frame transmission with index 0 */ 941 op->currframe = 0; 942 } 943 944 /* check flags */ 945 946 op->flags = msg_head->flags; 947 948 if (op->flags & TX_RESET_MULTI_IDX) { 949 /* start multiple frame transmission with index 0 */ 950 op->currframe = 0; 951 } 952 953 if (op->flags & SETTIMER) { 954 /* set timer values */ 955 op->count = msg_head->count; 956 op->ival1 = msg_head->ival1; 957 op->ival2 = msg_head->ival2; 958 op->kt_ival1 = timeval_to_ktime(msg_head->ival1); 959 op->kt_ival2 = timeval_to_ktime(msg_head->ival2); 960 961 /* disable an active timer due to zero values? */ 962 if (!op->kt_ival1.tv64 && !op->kt_ival2.tv64) 963 hrtimer_cancel(&op->timer); 964 } 965 966 if ((op->flags & STARTTIMER) && 967 ((op->kt_ival1.tv64 && op->count) || op->kt_ival2.tv64)) { 968 969 /* spec: send can_frame when starting timer */ 970 op->flags |= TX_ANNOUNCE; 971 972 if (op->kt_ival1.tv64 && (op->count > 0)) { 973 /* op->count-- is done in bcm_tx_timeout_handler */ 974 hrtimer_start(&op->timer, op->kt_ival1, 975 HRTIMER_MODE_REL); 976 } else 977 hrtimer_start(&op->timer, op->kt_ival2, 978 HRTIMER_MODE_REL); 979 } 980 981 if (op->flags & TX_ANNOUNCE) 982 bcm_can_tx(op); 983 984 return msg_head->nframes * CFSIZ + MHSIZ; 985 } 986 987 /* 988 * bcm_rx_setup - create or update a bcm rx op (for bcm_sendmsg) 989 */ 990 static int bcm_rx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg, 991 int ifindex, struct sock *sk) 992 { 993 struct bcm_sock *bo = bcm_sk(sk); 994 struct bcm_op *op; 995 int do_rx_register; 996 int err = 0; 997 998 if ((msg_head->flags & RX_FILTER_ID) || (!(msg_head->nframes))) { 999 /* be robust against wrong usage ... */ 1000 msg_head->flags |= RX_FILTER_ID; 1001 /* ignore trailing garbage */ 1002 msg_head->nframes = 0; 1003 } 1004 1005 /* the first element contains the mux-mask => MAX_NFRAMES + 1 */ 1006 if (msg_head->nframes > MAX_NFRAMES + 1) 1007 return -EINVAL; 1008 1009 if ((msg_head->flags & RX_RTR_FRAME) && 1010 ((msg_head->nframes != 1) || 1011 (!(msg_head->can_id & CAN_RTR_FLAG)))) 1012 return -EINVAL; 1013 1014 /* check the given can_id */ 1015 op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex); 1016 if (op) { 1017 /* update existing BCM operation */ 1018 1019 /* 1020 * Do we need more space for the can_frames than currently 1021 * allocated? -> This is a _really_ unusual use-case and 1022 * therefore (complexity / locking) it is not supported. 1023 */ 1024 if (msg_head->nframes > op->nframes) 1025 return -E2BIG; 1026 1027 if (msg_head->nframes) { 1028 /* update can_frames content */ 1029 err = memcpy_fromiovec((u8 *)op->frames, 1030 msg->msg_iov, 1031 msg_head->nframes * CFSIZ); 1032 if (err < 0) 1033 return err; 1034 1035 /* clear last_frames to indicate 'nothing received' */ 1036 memset(op->last_frames, 0, msg_head->nframes * CFSIZ); 1037 } 1038 1039 op->nframes = msg_head->nframes; 1040 1041 /* Only an update -> do not call can_rx_register() */ 1042 do_rx_register = 0; 1043 1044 } else { 1045 /* insert new BCM operation for the given can_id */ 1046 op = kzalloc(OPSIZ, GFP_KERNEL); 1047 if (!op) 1048 return -ENOMEM; 1049 1050 op->can_id = msg_head->can_id; 1051 op->nframes = msg_head->nframes; 1052 1053 if (msg_head->nframes > 1) { 1054 /* create array for can_frames and copy the data */ 1055 op->frames = kmalloc(msg_head->nframes * CFSIZ, 1056 GFP_KERNEL); 1057 if (!op->frames) { 1058 kfree(op); 1059 return -ENOMEM; 1060 } 1061 1062 /* create and init array for received can_frames */ 1063 op->last_frames = kzalloc(msg_head->nframes * CFSIZ, 1064 GFP_KERNEL); 1065 if (!op->last_frames) { 1066 kfree(op->frames); 1067 kfree(op); 1068 return -ENOMEM; 1069 } 1070 1071 } else { 1072 op->frames = &op->sframe; 1073 op->last_frames = &op->last_sframe; 1074 } 1075 1076 if (msg_head->nframes) { 1077 err = memcpy_fromiovec((u8 *)op->frames, msg->msg_iov, 1078 msg_head->nframes * CFSIZ); 1079 if (err < 0) { 1080 if (op->frames != &op->sframe) 1081 kfree(op->frames); 1082 if (op->last_frames != &op->last_sframe) 1083 kfree(op->last_frames); 1084 kfree(op); 1085 return err; 1086 } 1087 } 1088 1089 /* bcm_can_tx / bcm_tx_timeout_handler needs this */ 1090 op->sk = sk; 1091 op->ifindex = ifindex; 1092 1093 /* initialize uninitialized (kzalloc) structure */ 1094 hrtimer_init(&op->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); 1095 op->timer.function = bcm_rx_timeout_handler; 1096 1097 /* initialize tasklet for rx timeout notification */ 1098 tasklet_init(&op->tsklet, bcm_rx_timeout_tsklet, 1099 (unsigned long) op); 1100 1101 hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); 1102 op->thrtimer.function = bcm_rx_thr_handler; 1103 1104 /* initialize tasklet for rx throttle handling */ 1105 tasklet_init(&op->thrtsklet, bcm_rx_thr_tsklet, 1106 (unsigned long) op); 1107 1108 /* add this bcm_op to the list of the rx_ops */ 1109 list_add(&op->list, &bo->rx_ops); 1110 1111 /* call can_rx_register() */ 1112 do_rx_register = 1; 1113 1114 } /* if ((op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex))) */ 1115 1116 /* check flags */ 1117 op->flags = msg_head->flags; 1118 1119 if (op->flags & RX_RTR_FRAME) { 1120 1121 /* no timers in RTR-mode */ 1122 hrtimer_cancel(&op->thrtimer); 1123 hrtimer_cancel(&op->timer); 1124 1125 /* 1126 * funny feature in RX(!)_SETUP only for RTR-mode: 1127 * copy can_id into frame BUT without RTR-flag to 1128 * prevent a full-load-loopback-test ... ;-] 1129 */ 1130 if ((op->flags & TX_CP_CAN_ID) || 1131 (op->frames[0].can_id == op->can_id)) 1132 op->frames[0].can_id = op->can_id & ~CAN_RTR_FLAG; 1133 1134 } else { 1135 if (op->flags & SETTIMER) { 1136 1137 /* set timer value */ 1138 op->ival1 = msg_head->ival1; 1139 op->ival2 = msg_head->ival2; 1140 op->kt_ival1 = timeval_to_ktime(msg_head->ival1); 1141 op->kt_ival2 = timeval_to_ktime(msg_head->ival2); 1142 1143 /* disable an active timer due to zero value? */ 1144 if (!op->kt_ival1.tv64) 1145 hrtimer_cancel(&op->timer); 1146 1147 /* 1148 * In any case cancel the throttle timer, flush 1149 * potentially blocked msgs and reset throttle handling 1150 */ 1151 op->kt_lastmsg = ktime_set(0, 0); 1152 hrtimer_cancel(&op->thrtimer); 1153 bcm_rx_thr_flush(op, 1); 1154 } 1155 1156 if ((op->flags & STARTTIMER) && op->kt_ival1.tv64) 1157 hrtimer_start(&op->timer, op->kt_ival1, 1158 HRTIMER_MODE_REL); 1159 } 1160 1161 /* now we can register for can_ids, if we added a new bcm_op */ 1162 if (do_rx_register) { 1163 if (ifindex) { 1164 struct net_device *dev; 1165 1166 dev = dev_get_by_index(&init_net, ifindex); 1167 if (dev) { 1168 err = can_rx_register(dev, op->can_id, 1169 REGMASK(op->can_id), 1170 bcm_rx_handler, op, 1171 "bcm"); 1172 1173 op->rx_reg_dev = dev; 1174 dev_put(dev); 1175 } 1176 1177 } else 1178 err = can_rx_register(NULL, op->can_id, 1179 REGMASK(op->can_id), 1180 bcm_rx_handler, op, "bcm"); 1181 if (err) { 1182 /* this bcm rx op is broken -> remove it */ 1183 list_del(&op->list); 1184 bcm_remove_op(op); 1185 return err; 1186 } 1187 } 1188 1189 return msg_head->nframes * CFSIZ + MHSIZ; 1190 } 1191 1192 /* 1193 * bcm_tx_send - send a single CAN frame to the CAN interface (for bcm_sendmsg) 1194 */ 1195 static int bcm_tx_send(struct msghdr *msg, int ifindex, struct sock *sk) 1196 { 1197 struct sk_buff *skb; 1198 struct net_device *dev; 1199 int err; 1200 1201 /* we need a real device to send frames */ 1202 if (!ifindex) 1203 return -ENODEV; 1204 1205 skb = alloc_skb(CFSIZ, GFP_KERNEL); 1206 1207 if (!skb) 1208 return -ENOMEM; 1209 1210 err = memcpy_fromiovec(skb_put(skb, CFSIZ), msg->msg_iov, CFSIZ); 1211 if (err < 0) { 1212 kfree_skb(skb); 1213 return err; 1214 } 1215 1216 dev = dev_get_by_index(&init_net, ifindex); 1217 if (!dev) { 1218 kfree_skb(skb); 1219 return -ENODEV; 1220 } 1221 1222 skb->dev = dev; 1223 skb->sk = sk; 1224 err = can_send(skb, 1); /* send with loopback */ 1225 dev_put(dev); 1226 1227 if (err) 1228 return err; 1229 1230 return CFSIZ + MHSIZ; 1231 } 1232 1233 /* 1234 * bcm_sendmsg - process BCM commands (opcodes) from the userspace 1235 */ 1236 static int bcm_sendmsg(struct kiocb *iocb, struct socket *sock, 1237 struct msghdr *msg, size_t size) 1238 { 1239 struct sock *sk = sock->sk; 1240 struct bcm_sock *bo = bcm_sk(sk); 1241 int ifindex = bo->ifindex; /* default ifindex for this bcm_op */ 1242 struct bcm_msg_head msg_head; 1243 int ret; /* read bytes or error codes as return value */ 1244 1245 if (!bo->bound) 1246 return -ENOTCONN; 1247 1248 /* check for valid message length from userspace */ 1249 if (size < MHSIZ || (size - MHSIZ) % CFSIZ) 1250 return -EINVAL; 1251 1252 /* check for alternative ifindex for this bcm_op */ 1253 1254 if (!ifindex && msg->msg_name) { 1255 /* no bound device as default => check msg_name */ 1256 struct sockaddr_can *addr = 1257 (struct sockaddr_can *)msg->msg_name; 1258 1259 if (msg->msg_namelen < sizeof(*addr)) 1260 return -EINVAL; 1261 1262 if (addr->can_family != AF_CAN) 1263 return -EINVAL; 1264 1265 /* ifindex from sendto() */ 1266 ifindex = addr->can_ifindex; 1267 1268 if (ifindex) { 1269 struct net_device *dev; 1270 1271 dev = dev_get_by_index(&init_net, ifindex); 1272 if (!dev) 1273 return -ENODEV; 1274 1275 if (dev->type != ARPHRD_CAN) { 1276 dev_put(dev); 1277 return -ENODEV; 1278 } 1279 1280 dev_put(dev); 1281 } 1282 } 1283 1284 /* read message head information */ 1285 1286 ret = memcpy_fromiovec((u8 *)&msg_head, msg->msg_iov, MHSIZ); 1287 if (ret < 0) 1288 return ret; 1289 1290 lock_sock(sk); 1291 1292 switch (msg_head.opcode) { 1293 1294 case TX_SETUP: 1295 ret = bcm_tx_setup(&msg_head, msg, ifindex, sk); 1296 break; 1297 1298 case RX_SETUP: 1299 ret = bcm_rx_setup(&msg_head, msg, ifindex, sk); 1300 break; 1301 1302 case TX_DELETE: 1303 if (bcm_delete_tx_op(&bo->tx_ops, msg_head.can_id, ifindex)) 1304 ret = MHSIZ; 1305 else 1306 ret = -EINVAL; 1307 break; 1308 1309 case RX_DELETE: 1310 if (bcm_delete_rx_op(&bo->rx_ops, msg_head.can_id, ifindex)) 1311 ret = MHSIZ; 1312 else 1313 ret = -EINVAL; 1314 break; 1315 1316 case TX_READ: 1317 /* reuse msg_head for the reply to TX_READ */ 1318 msg_head.opcode = TX_STATUS; 1319 ret = bcm_read_op(&bo->tx_ops, &msg_head, ifindex); 1320 break; 1321 1322 case RX_READ: 1323 /* reuse msg_head for the reply to RX_READ */ 1324 msg_head.opcode = RX_STATUS; 1325 ret = bcm_read_op(&bo->rx_ops, &msg_head, ifindex); 1326 break; 1327 1328 case TX_SEND: 1329 /* we need exactly one can_frame behind the msg head */ 1330 if ((msg_head.nframes != 1) || (size != CFSIZ + MHSIZ)) 1331 ret = -EINVAL; 1332 else 1333 ret = bcm_tx_send(msg, ifindex, sk); 1334 break; 1335 1336 default: 1337 ret = -EINVAL; 1338 break; 1339 } 1340 1341 release_sock(sk); 1342 1343 return ret; 1344 } 1345 1346 /* 1347 * notification handler for netdevice status changes 1348 */ 1349 static int bcm_notifier(struct notifier_block *nb, unsigned long msg, 1350 void *data) 1351 { 1352 struct net_device *dev = (struct net_device *)data; 1353 struct bcm_sock *bo = container_of(nb, struct bcm_sock, notifier); 1354 struct sock *sk = &bo->sk; 1355 struct bcm_op *op; 1356 int notify_enodev = 0; 1357 1358 if (!net_eq(dev_net(dev), &init_net)) 1359 return NOTIFY_DONE; 1360 1361 if (dev->type != ARPHRD_CAN) 1362 return NOTIFY_DONE; 1363 1364 switch (msg) { 1365 1366 case NETDEV_UNREGISTER: 1367 lock_sock(sk); 1368 1369 /* remove device specific receive entries */ 1370 list_for_each_entry(op, &bo->rx_ops, list) 1371 if (op->rx_reg_dev == dev) 1372 bcm_rx_unreg(dev, op); 1373 1374 /* remove device reference, if this is our bound device */ 1375 if (bo->bound && bo->ifindex == dev->ifindex) { 1376 bo->bound = 0; 1377 bo->ifindex = 0; 1378 notify_enodev = 1; 1379 } 1380 1381 release_sock(sk); 1382 1383 if (notify_enodev) { 1384 sk->sk_err = ENODEV; 1385 if (!sock_flag(sk, SOCK_DEAD)) 1386 sk->sk_error_report(sk); 1387 } 1388 break; 1389 1390 case NETDEV_DOWN: 1391 if (bo->bound && bo->ifindex == dev->ifindex) { 1392 sk->sk_err = ENETDOWN; 1393 if (!sock_flag(sk, SOCK_DEAD)) 1394 sk->sk_error_report(sk); 1395 } 1396 } 1397 1398 return NOTIFY_DONE; 1399 } 1400 1401 /* 1402 * initial settings for all BCM sockets to be set at socket creation time 1403 */ 1404 static int bcm_init(struct sock *sk) 1405 { 1406 struct bcm_sock *bo = bcm_sk(sk); 1407 1408 bo->bound = 0; 1409 bo->ifindex = 0; 1410 bo->dropped_usr_msgs = 0; 1411 bo->bcm_proc_read = NULL; 1412 1413 INIT_LIST_HEAD(&bo->tx_ops); 1414 INIT_LIST_HEAD(&bo->rx_ops); 1415 1416 /* set notifier */ 1417 bo->notifier.notifier_call = bcm_notifier; 1418 1419 register_netdevice_notifier(&bo->notifier); 1420 1421 return 0; 1422 } 1423 1424 /* 1425 * standard socket functions 1426 */ 1427 static int bcm_release(struct socket *sock) 1428 { 1429 struct sock *sk = sock->sk; 1430 struct bcm_sock *bo; 1431 struct bcm_op *op, *next; 1432 1433 if (sk == NULL) 1434 return 0; 1435 1436 bo = bcm_sk(sk); 1437 1438 /* remove bcm_ops, timer, rx_unregister(), etc. */ 1439 1440 unregister_netdevice_notifier(&bo->notifier); 1441 1442 lock_sock(sk); 1443 1444 list_for_each_entry_safe(op, next, &bo->tx_ops, list) 1445 bcm_remove_op(op); 1446 1447 list_for_each_entry_safe(op, next, &bo->rx_ops, list) { 1448 /* 1449 * Don't care if we're bound or not (due to netdev problems) 1450 * can_rx_unregister() is always a save thing to do here. 1451 */ 1452 if (op->ifindex) { 1453 /* 1454 * Only remove subscriptions that had not 1455 * been removed due to NETDEV_UNREGISTER 1456 * in bcm_notifier() 1457 */ 1458 if (op->rx_reg_dev) { 1459 struct net_device *dev; 1460 1461 dev = dev_get_by_index(&init_net, op->ifindex); 1462 if (dev) { 1463 bcm_rx_unreg(dev, op); 1464 dev_put(dev); 1465 } 1466 } 1467 } else 1468 can_rx_unregister(NULL, op->can_id, 1469 REGMASK(op->can_id), 1470 bcm_rx_handler, op); 1471 1472 bcm_remove_op(op); 1473 } 1474 1475 /* remove procfs entry */ 1476 if (proc_dir && bo->bcm_proc_read) 1477 remove_proc_entry(bo->procname, proc_dir); 1478 1479 /* remove device reference */ 1480 if (bo->bound) { 1481 bo->bound = 0; 1482 bo->ifindex = 0; 1483 } 1484 1485 sock_orphan(sk); 1486 sock->sk = NULL; 1487 1488 release_sock(sk); 1489 sock_put(sk); 1490 1491 return 0; 1492 } 1493 1494 static int bcm_connect(struct socket *sock, struct sockaddr *uaddr, int len, 1495 int flags) 1496 { 1497 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; 1498 struct sock *sk = sock->sk; 1499 struct bcm_sock *bo = bcm_sk(sk); 1500 1501 if (len < sizeof(*addr)) 1502 return -EINVAL; 1503 1504 if (bo->bound) 1505 return -EISCONN; 1506 1507 /* bind a device to this socket */ 1508 if (addr->can_ifindex) { 1509 struct net_device *dev; 1510 1511 dev = dev_get_by_index(&init_net, addr->can_ifindex); 1512 if (!dev) 1513 return -ENODEV; 1514 1515 if (dev->type != ARPHRD_CAN) { 1516 dev_put(dev); 1517 return -ENODEV; 1518 } 1519 1520 bo->ifindex = dev->ifindex; 1521 dev_put(dev); 1522 1523 } else { 1524 /* no interface reference for ifindex = 0 ('any' CAN device) */ 1525 bo->ifindex = 0; 1526 } 1527 1528 bo->bound = 1; 1529 1530 if (proc_dir) { 1531 /* unique socket address as filename */ 1532 sprintf(bo->procname, "%lu", sock_i_ino(sk)); 1533 bo->bcm_proc_read = proc_create_data(bo->procname, 0644, 1534 proc_dir, 1535 &bcm_proc_fops, sk); 1536 } 1537 1538 return 0; 1539 } 1540 1541 static int bcm_recvmsg(struct kiocb *iocb, struct socket *sock, 1542 struct msghdr *msg, size_t size, int flags) 1543 { 1544 struct sock *sk = sock->sk; 1545 struct sk_buff *skb; 1546 int error = 0; 1547 int noblock; 1548 int err; 1549 1550 noblock = flags & MSG_DONTWAIT; 1551 flags &= ~MSG_DONTWAIT; 1552 skb = skb_recv_datagram(sk, flags, noblock, &error); 1553 if (!skb) 1554 return error; 1555 1556 if (skb->len < size) 1557 size = skb->len; 1558 1559 err = memcpy_toiovec(msg->msg_iov, skb->data, size); 1560 if (err < 0) { 1561 skb_free_datagram(sk, skb); 1562 return err; 1563 } 1564 1565 sock_recv_ts_and_drops(msg, sk, skb); 1566 1567 if (msg->msg_name) { 1568 msg->msg_namelen = sizeof(struct sockaddr_can); 1569 memcpy(msg->msg_name, skb->cb, msg->msg_namelen); 1570 } 1571 1572 skb_free_datagram(sk, skb); 1573 1574 return size; 1575 } 1576 1577 static const struct proto_ops bcm_ops = { 1578 .family = PF_CAN, 1579 .release = bcm_release, 1580 .bind = sock_no_bind, 1581 .connect = bcm_connect, 1582 .socketpair = sock_no_socketpair, 1583 .accept = sock_no_accept, 1584 .getname = sock_no_getname, 1585 .poll = datagram_poll, 1586 .ioctl = can_ioctl, /* use can_ioctl() from af_can.c */ 1587 .listen = sock_no_listen, 1588 .shutdown = sock_no_shutdown, 1589 .setsockopt = sock_no_setsockopt, 1590 .getsockopt = sock_no_getsockopt, 1591 .sendmsg = bcm_sendmsg, 1592 .recvmsg = bcm_recvmsg, 1593 .mmap = sock_no_mmap, 1594 .sendpage = sock_no_sendpage, 1595 }; 1596 1597 static struct proto bcm_proto __read_mostly = { 1598 .name = "CAN_BCM", 1599 .owner = THIS_MODULE, 1600 .obj_size = sizeof(struct bcm_sock), 1601 .init = bcm_init, 1602 }; 1603 1604 static const struct can_proto bcm_can_proto = { 1605 .type = SOCK_DGRAM, 1606 .protocol = CAN_BCM, 1607 .ops = &bcm_ops, 1608 .prot = &bcm_proto, 1609 }; 1610 1611 static int __init bcm_module_init(void) 1612 { 1613 int err; 1614 1615 printk(banner); 1616 1617 err = can_proto_register(&bcm_can_proto); 1618 if (err < 0) { 1619 printk(KERN_ERR "can: registration of bcm protocol failed\n"); 1620 return err; 1621 } 1622 1623 /* create /proc/net/can-bcm directory */ 1624 proc_dir = proc_mkdir("can-bcm", init_net.proc_net); 1625 return 0; 1626 } 1627 1628 static void __exit bcm_module_exit(void) 1629 { 1630 can_proto_unregister(&bcm_can_proto); 1631 1632 if (proc_dir) 1633 proc_net_remove(&init_net, "can-bcm"); 1634 } 1635 1636 module_init(bcm_module_init); 1637 module_exit(bcm_module_exit); 1638