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