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 return; 718 } 719 720 static void bcm_rx_unreg(struct net_device *dev, struct bcm_op *op) 721 { 722 if (op->rx_reg_dev == dev) { 723 can_rx_unregister(dev, op->can_id, REGMASK(op->can_id), 724 bcm_rx_handler, op); 725 726 /* mark as removed subscription */ 727 op->rx_reg_dev = NULL; 728 } else 729 printk(KERN_ERR "can-bcm: bcm_rx_unreg: registered device " 730 "mismatch %p %p\n", op->rx_reg_dev, dev); 731 } 732 733 /* 734 * bcm_delete_rx_op - find and remove a rx op (returns number of removed ops) 735 */ 736 static int bcm_delete_rx_op(struct list_head *ops, canid_t can_id, int ifindex) 737 { 738 struct bcm_op *op, *n; 739 740 list_for_each_entry_safe(op, n, ops, list) { 741 if ((op->can_id == can_id) && (op->ifindex == ifindex)) { 742 743 /* 744 * Don't care if we're bound or not (due to netdev 745 * problems) can_rx_unregister() is always a save 746 * thing to do here. 747 */ 748 if (op->ifindex) { 749 /* 750 * Only remove subscriptions that had not 751 * been removed due to NETDEV_UNREGISTER 752 * in bcm_notifier() 753 */ 754 if (op->rx_reg_dev) { 755 struct net_device *dev; 756 757 dev = dev_get_by_index(&init_net, 758 op->ifindex); 759 if (dev) { 760 bcm_rx_unreg(dev, op); 761 dev_put(dev); 762 } 763 } 764 } else 765 can_rx_unregister(NULL, op->can_id, 766 REGMASK(op->can_id), 767 bcm_rx_handler, op); 768 769 list_del(&op->list); 770 bcm_remove_op(op); 771 return 1; /* done */ 772 } 773 } 774 775 return 0; /* not found */ 776 } 777 778 /* 779 * bcm_delete_tx_op - find and remove a tx op (returns number of removed ops) 780 */ 781 static int bcm_delete_tx_op(struct list_head *ops, canid_t can_id, int ifindex) 782 { 783 struct bcm_op *op, *n; 784 785 list_for_each_entry_safe(op, n, ops, list) { 786 if ((op->can_id == can_id) && (op->ifindex == ifindex)) { 787 list_del(&op->list); 788 bcm_remove_op(op); 789 return 1; /* done */ 790 } 791 } 792 793 return 0; /* not found */ 794 } 795 796 /* 797 * bcm_read_op - read out a bcm_op and send it to the user (for bcm_sendmsg) 798 */ 799 static int bcm_read_op(struct list_head *ops, struct bcm_msg_head *msg_head, 800 int ifindex) 801 { 802 struct bcm_op *op = bcm_find_op(ops, msg_head->can_id, ifindex); 803 804 if (!op) 805 return -EINVAL; 806 807 /* put current values into msg_head */ 808 msg_head->flags = op->flags; 809 msg_head->count = op->count; 810 msg_head->ival1 = op->ival1; 811 msg_head->ival2 = op->ival2; 812 msg_head->nframes = op->nframes; 813 814 bcm_send_to_user(op, msg_head, op->frames, 0); 815 816 return MHSIZ; 817 } 818 819 /* 820 * bcm_tx_setup - create or update a bcm tx op (for bcm_sendmsg) 821 */ 822 static int bcm_tx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg, 823 int ifindex, struct sock *sk) 824 { 825 struct bcm_sock *bo = bcm_sk(sk); 826 struct bcm_op *op; 827 int i, err; 828 829 /* we need a real device to send frames */ 830 if (!ifindex) 831 return -ENODEV; 832 833 /* we need at least one can_frame */ 834 if (msg_head->nframes < 1) 835 return -EINVAL; 836 837 /* check the given can_id */ 838 op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex); 839 840 if (op) { 841 /* update existing BCM operation */ 842 843 /* 844 * Do we need more space for the can_frames than currently 845 * allocated? -> This is a _really_ unusual use-case and 846 * therefore (complexity / locking) it is not supported. 847 */ 848 if (msg_head->nframes > op->nframes) 849 return -E2BIG; 850 851 /* update can_frames content */ 852 for (i = 0; i < msg_head->nframes; i++) { 853 err = memcpy_fromiovec((u8 *)&op->frames[i], 854 msg->msg_iov, CFSIZ); 855 856 if (op->frames[i].can_dlc > 8) 857 err = -EINVAL; 858 859 if (err < 0) 860 return err; 861 862 if (msg_head->flags & TX_CP_CAN_ID) { 863 /* copy can_id into frame */ 864 op->frames[i].can_id = msg_head->can_id; 865 } 866 } 867 868 } else { 869 /* insert new BCM operation for the given can_id */ 870 871 op = kzalloc(OPSIZ, GFP_KERNEL); 872 if (!op) 873 return -ENOMEM; 874 875 op->can_id = msg_head->can_id; 876 877 /* create array for can_frames and copy the data */ 878 if (msg_head->nframes > 1) { 879 op->frames = kmalloc(msg_head->nframes * CFSIZ, 880 GFP_KERNEL); 881 if (!op->frames) { 882 kfree(op); 883 return -ENOMEM; 884 } 885 } else 886 op->frames = &op->sframe; 887 888 for (i = 0; i < msg_head->nframes; i++) { 889 err = memcpy_fromiovec((u8 *)&op->frames[i], 890 msg->msg_iov, CFSIZ); 891 892 if (op->frames[i].can_dlc > 8) 893 err = -EINVAL; 894 895 if (err < 0) { 896 if (op->frames != &op->sframe) 897 kfree(op->frames); 898 kfree(op); 899 return err; 900 } 901 902 if (msg_head->flags & TX_CP_CAN_ID) { 903 /* copy can_id into frame */ 904 op->frames[i].can_id = msg_head->can_id; 905 } 906 } 907 908 /* tx_ops never compare with previous received messages */ 909 op->last_frames = NULL; 910 911 /* bcm_can_tx / bcm_tx_timeout_handler needs this */ 912 op->sk = sk; 913 op->ifindex = ifindex; 914 915 /* initialize uninitialized (kzalloc) structure */ 916 hrtimer_init(&op->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); 917 op->timer.function = bcm_tx_timeout_handler; 918 919 /* initialize tasklet for tx countevent notification */ 920 tasklet_init(&op->tsklet, bcm_tx_timeout_tsklet, 921 (unsigned long) op); 922 923 /* currently unused in tx_ops */ 924 hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); 925 926 /* add this bcm_op to the list of the tx_ops */ 927 list_add(&op->list, &bo->tx_ops); 928 929 } /* if ((op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex))) */ 930 931 if (op->nframes != msg_head->nframes) { 932 op->nframes = msg_head->nframes; 933 /* start multiple frame transmission with index 0 */ 934 op->currframe = 0; 935 } 936 937 /* check flags */ 938 939 op->flags = msg_head->flags; 940 941 if (op->flags & TX_RESET_MULTI_IDX) { 942 /* start multiple frame transmission with index 0 */ 943 op->currframe = 0; 944 } 945 946 if (op->flags & SETTIMER) { 947 /* set timer values */ 948 op->count = msg_head->count; 949 op->ival1 = msg_head->ival1; 950 op->ival2 = msg_head->ival2; 951 op->kt_ival1 = timeval_to_ktime(msg_head->ival1); 952 op->kt_ival2 = timeval_to_ktime(msg_head->ival2); 953 954 /* disable an active timer due to zero values? */ 955 if (!op->kt_ival1.tv64 && !op->kt_ival2.tv64) 956 hrtimer_cancel(&op->timer); 957 } 958 959 if ((op->flags & STARTTIMER) && 960 ((op->kt_ival1.tv64 && op->count) || op->kt_ival2.tv64)) { 961 962 /* spec: send can_frame when starting timer */ 963 op->flags |= TX_ANNOUNCE; 964 965 if (op->kt_ival1.tv64 && (op->count > 0)) { 966 /* op->count-- is done in bcm_tx_timeout_handler */ 967 hrtimer_start(&op->timer, op->kt_ival1, 968 HRTIMER_MODE_REL); 969 } else 970 hrtimer_start(&op->timer, op->kt_ival2, 971 HRTIMER_MODE_REL); 972 } 973 974 if (op->flags & TX_ANNOUNCE) 975 bcm_can_tx(op); 976 977 return msg_head->nframes * CFSIZ + MHSIZ; 978 } 979 980 /* 981 * bcm_rx_setup - create or update a bcm rx op (for bcm_sendmsg) 982 */ 983 static int bcm_rx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg, 984 int ifindex, struct sock *sk) 985 { 986 struct bcm_sock *bo = bcm_sk(sk); 987 struct bcm_op *op; 988 int do_rx_register; 989 int err = 0; 990 991 if ((msg_head->flags & RX_FILTER_ID) || (!(msg_head->nframes))) { 992 /* be robust against wrong usage ... */ 993 msg_head->flags |= RX_FILTER_ID; 994 /* ignore trailing garbage */ 995 msg_head->nframes = 0; 996 } 997 998 if ((msg_head->flags & RX_RTR_FRAME) && 999 ((msg_head->nframes != 1) || 1000 (!(msg_head->can_id & CAN_RTR_FLAG)))) 1001 return -EINVAL; 1002 1003 /* check the given can_id */ 1004 op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex); 1005 if (op) { 1006 /* update existing BCM operation */ 1007 1008 /* 1009 * Do we need more space for the can_frames than currently 1010 * allocated? -> This is a _really_ unusual use-case and 1011 * therefore (complexity / locking) it is not supported. 1012 */ 1013 if (msg_head->nframes > op->nframes) 1014 return -E2BIG; 1015 1016 if (msg_head->nframes) { 1017 /* update can_frames content */ 1018 err = memcpy_fromiovec((u8 *)op->frames, 1019 msg->msg_iov, 1020 msg_head->nframes * CFSIZ); 1021 if (err < 0) 1022 return err; 1023 1024 /* clear last_frames to indicate 'nothing received' */ 1025 memset(op->last_frames, 0, msg_head->nframes * CFSIZ); 1026 } 1027 1028 op->nframes = msg_head->nframes; 1029 1030 /* Only an update -> do not call can_rx_register() */ 1031 do_rx_register = 0; 1032 1033 } else { 1034 /* insert new BCM operation for the given can_id */ 1035 op = kzalloc(OPSIZ, GFP_KERNEL); 1036 if (!op) 1037 return -ENOMEM; 1038 1039 op->can_id = msg_head->can_id; 1040 op->nframes = msg_head->nframes; 1041 1042 if (msg_head->nframes > 1) { 1043 /* create array for can_frames and copy the data */ 1044 op->frames = kmalloc(msg_head->nframes * CFSIZ, 1045 GFP_KERNEL); 1046 if (!op->frames) { 1047 kfree(op); 1048 return -ENOMEM; 1049 } 1050 1051 /* create and init array for received can_frames */ 1052 op->last_frames = kzalloc(msg_head->nframes * CFSIZ, 1053 GFP_KERNEL); 1054 if (!op->last_frames) { 1055 kfree(op->frames); 1056 kfree(op); 1057 return -ENOMEM; 1058 } 1059 1060 } else { 1061 op->frames = &op->sframe; 1062 op->last_frames = &op->last_sframe; 1063 } 1064 1065 if (msg_head->nframes) { 1066 err = memcpy_fromiovec((u8 *)op->frames, msg->msg_iov, 1067 msg_head->nframes * CFSIZ); 1068 if (err < 0) { 1069 if (op->frames != &op->sframe) 1070 kfree(op->frames); 1071 if (op->last_frames != &op->last_sframe) 1072 kfree(op->last_frames); 1073 kfree(op); 1074 return err; 1075 } 1076 } 1077 1078 /* bcm_can_tx / bcm_tx_timeout_handler needs this */ 1079 op->sk = sk; 1080 op->ifindex = ifindex; 1081 1082 /* initialize uninitialized (kzalloc) structure */ 1083 hrtimer_init(&op->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); 1084 op->timer.function = bcm_rx_timeout_handler; 1085 1086 /* initialize tasklet for rx timeout notification */ 1087 tasklet_init(&op->tsklet, bcm_rx_timeout_tsklet, 1088 (unsigned long) op); 1089 1090 hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); 1091 op->thrtimer.function = bcm_rx_thr_handler; 1092 1093 /* initialize tasklet for rx throttle handling */ 1094 tasklet_init(&op->thrtsklet, bcm_rx_thr_tsklet, 1095 (unsigned long) op); 1096 1097 /* add this bcm_op to the list of the rx_ops */ 1098 list_add(&op->list, &bo->rx_ops); 1099 1100 /* call can_rx_register() */ 1101 do_rx_register = 1; 1102 1103 } /* if ((op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex))) */ 1104 1105 /* check flags */ 1106 op->flags = msg_head->flags; 1107 1108 if (op->flags & RX_RTR_FRAME) { 1109 1110 /* no timers in RTR-mode */ 1111 hrtimer_cancel(&op->thrtimer); 1112 hrtimer_cancel(&op->timer); 1113 1114 /* 1115 * funny feature in RX(!)_SETUP only for RTR-mode: 1116 * copy can_id into frame BUT without RTR-flag to 1117 * prevent a full-load-loopback-test ... ;-] 1118 */ 1119 if ((op->flags & TX_CP_CAN_ID) || 1120 (op->frames[0].can_id == op->can_id)) 1121 op->frames[0].can_id = op->can_id & ~CAN_RTR_FLAG; 1122 1123 } else { 1124 if (op->flags & SETTIMER) { 1125 1126 /* set timer value */ 1127 op->ival1 = msg_head->ival1; 1128 op->ival2 = msg_head->ival2; 1129 op->kt_ival1 = timeval_to_ktime(msg_head->ival1); 1130 op->kt_ival2 = timeval_to_ktime(msg_head->ival2); 1131 1132 /* disable an active timer due to zero value? */ 1133 if (!op->kt_ival1.tv64) 1134 hrtimer_cancel(&op->timer); 1135 1136 /* 1137 * In any case cancel the throttle timer, flush 1138 * potentially blocked msgs and reset throttle handling 1139 */ 1140 op->kt_lastmsg = ktime_set(0, 0); 1141 hrtimer_cancel(&op->thrtimer); 1142 bcm_rx_thr_flush(op, 1); 1143 } 1144 1145 if ((op->flags & STARTTIMER) && op->kt_ival1.tv64) 1146 hrtimer_start(&op->timer, op->kt_ival1, 1147 HRTIMER_MODE_REL); 1148 } 1149 1150 /* now we can register for can_ids, if we added a new bcm_op */ 1151 if (do_rx_register) { 1152 if (ifindex) { 1153 struct net_device *dev; 1154 1155 dev = dev_get_by_index(&init_net, ifindex); 1156 if (dev) { 1157 err = can_rx_register(dev, op->can_id, 1158 REGMASK(op->can_id), 1159 bcm_rx_handler, op, 1160 "bcm"); 1161 1162 op->rx_reg_dev = dev; 1163 dev_put(dev); 1164 } 1165 1166 } else 1167 err = can_rx_register(NULL, op->can_id, 1168 REGMASK(op->can_id), 1169 bcm_rx_handler, op, "bcm"); 1170 if (err) { 1171 /* this bcm rx op is broken -> remove it */ 1172 list_del(&op->list); 1173 bcm_remove_op(op); 1174 return err; 1175 } 1176 } 1177 1178 return msg_head->nframes * CFSIZ + MHSIZ; 1179 } 1180 1181 /* 1182 * bcm_tx_send - send a single CAN frame to the CAN interface (for bcm_sendmsg) 1183 */ 1184 static int bcm_tx_send(struct msghdr *msg, int ifindex, struct sock *sk) 1185 { 1186 struct sk_buff *skb; 1187 struct net_device *dev; 1188 int err; 1189 1190 /* we need a real device to send frames */ 1191 if (!ifindex) 1192 return -ENODEV; 1193 1194 skb = alloc_skb(CFSIZ, GFP_KERNEL); 1195 1196 if (!skb) 1197 return -ENOMEM; 1198 1199 err = memcpy_fromiovec(skb_put(skb, CFSIZ), msg->msg_iov, CFSIZ); 1200 if (err < 0) { 1201 kfree_skb(skb); 1202 return err; 1203 } 1204 1205 dev = dev_get_by_index(&init_net, ifindex); 1206 if (!dev) { 1207 kfree_skb(skb); 1208 return -ENODEV; 1209 } 1210 1211 skb->dev = dev; 1212 skb->sk = sk; 1213 err = can_send(skb, 1); /* send with loopback */ 1214 dev_put(dev); 1215 1216 if (err) 1217 return err; 1218 1219 return CFSIZ + MHSIZ; 1220 } 1221 1222 /* 1223 * bcm_sendmsg - process BCM commands (opcodes) from the userspace 1224 */ 1225 static int bcm_sendmsg(struct kiocb *iocb, struct socket *sock, 1226 struct msghdr *msg, size_t size) 1227 { 1228 struct sock *sk = sock->sk; 1229 struct bcm_sock *bo = bcm_sk(sk); 1230 int ifindex = bo->ifindex; /* default ifindex for this bcm_op */ 1231 struct bcm_msg_head msg_head; 1232 int ret; /* read bytes or error codes as return value */ 1233 1234 if (!bo->bound) 1235 return -ENOTCONN; 1236 1237 /* check for valid message length from userspace */ 1238 if (size < MHSIZ || (size - MHSIZ) % CFSIZ) 1239 return -EINVAL; 1240 1241 /* check for alternative ifindex for this bcm_op */ 1242 1243 if (!ifindex && msg->msg_name) { 1244 /* no bound device as default => check msg_name */ 1245 struct sockaddr_can *addr = 1246 (struct sockaddr_can *)msg->msg_name; 1247 1248 if (addr->can_family != AF_CAN) 1249 return -EINVAL; 1250 1251 /* ifindex from sendto() */ 1252 ifindex = addr->can_ifindex; 1253 1254 if (ifindex) { 1255 struct net_device *dev; 1256 1257 dev = dev_get_by_index(&init_net, ifindex); 1258 if (!dev) 1259 return -ENODEV; 1260 1261 if (dev->type != ARPHRD_CAN) { 1262 dev_put(dev); 1263 return -ENODEV; 1264 } 1265 1266 dev_put(dev); 1267 } 1268 } 1269 1270 /* read message head information */ 1271 1272 ret = memcpy_fromiovec((u8 *)&msg_head, msg->msg_iov, MHSIZ); 1273 if (ret < 0) 1274 return ret; 1275 1276 lock_sock(sk); 1277 1278 switch (msg_head.opcode) { 1279 1280 case TX_SETUP: 1281 ret = bcm_tx_setup(&msg_head, msg, ifindex, sk); 1282 break; 1283 1284 case RX_SETUP: 1285 ret = bcm_rx_setup(&msg_head, msg, ifindex, sk); 1286 break; 1287 1288 case TX_DELETE: 1289 if (bcm_delete_tx_op(&bo->tx_ops, msg_head.can_id, ifindex)) 1290 ret = MHSIZ; 1291 else 1292 ret = -EINVAL; 1293 break; 1294 1295 case RX_DELETE: 1296 if (bcm_delete_rx_op(&bo->rx_ops, msg_head.can_id, ifindex)) 1297 ret = MHSIZ; 1298 else 1299 ret = -EINVAL; 1300 break; 1301 1302 case TX_READ: 1303 /* reuse msg_head for the reply to TX_READ */ 1304 msg_head.opcode = TX_STATUS; 1305 ret = bcm_read_op(&bo->tx_ops, &msg_head, ifindex); 1306 break; 1307 1308 case RX_READ: 1309 /* reuse msg_head for the reply to RX_READ */ 1310 msg_head.opcode = RX_STATUS; 1311 ret = bcm_read_op(&bo->rx_ops, &msg_head, ifindex); 1312 break; 1313 1314 case TX_SEND: 1315 /* we need exactly one can_frame behind the msg head */ 1316 if ((msg_head.nframes != 1) || (size != CFSIZ + MHSIZ)) 1317 ret = -EINVAL; 1318 else 1319 ret = bcm_tx_send(msg, ifindex, sk); 1320 break; 1321 1322 default: 1323 ret = -EINVAL; 1324 break; 1325 } 1326 1327 release_sock(sk); 1328 1329 return ret; 1330 } 1331 1332 /* 1333 * notification handler for netdevice status changes 1334 */ 1335 static int bcm_notifier(struct notifier_block *nb, unsigned long msg, 1336 void *data) 1337 { 1338 struct net_device *dev = (struct net_device *)data; 1339 struct bcm_sock *bo = container_of(nb, struct bcm_sock, notifier); 1340 struct sock *sk = &bo->sk; 1341 struct bcm_op *op; 1342 int notify_enodev = 0; 1343 1344 if (!net_eq(dev_net(dev), &init_net)) 1345 return NOTIFY_DONE; 1346 1347 if (dev->type != ARPHRD_CAN) 1348 return NOTIFY_DONE; 1349 1350 switch (msg) { 1351 1352 case NETDEV_UNREGISTER: 1353 lock_sock(sk); 1354 1355 /* remove device specific receive entries */ 1356 list_for_each_entry(op, &bo->rx_ops, list) 1357 if (op->rx_reg_dev == dev) 1358 bcm_rx_unreg(dev, op); 1359 1360 /* remove device reference, if this is our bound device */ 1361 if (bo->bound && bo->ifindex == dev->ifindex) { 1362 bo->bound = 0; 1363 bo->ifindex = 0; 1364 notify_enodev = 1; 1365 } 1366 1367 release_sock(sk); 1368 1369 if (notify_enodev) { 1370 sk->sk_err = ENODEV; 1371 if (!sock_flag(sk, SOCK_DEAD)) 1372 sk->sk_error_report(sk); 1373 } 1374 break; 1375 1376 case NETDEV_DOWN: 1377 if (bo->bound && bo->ifindex == dev->ifindex) { 1378 sk->sk_err = ENETDOWN; 1379 if (!sock_flag(sk, SOCK_DEAD)) 1380 sk->sk_error_report(sk); 1381 } 1382 } 1383 1384 return NOTIFY_DONE; 1385 } 1386 1387 /* 1388 * initial settings for all BCM sockets to be set at socket creation time 1389 */ 1390 static int bcm_init(struct sock *sk) 1391 { 1392 struct bcm_sock *bo = bcm_sk(sk); 1393 1394 bo->bound = 0; 1395 bo->ifindex = 0; 1396 bo->dropped_usr_msgs = 0; 1397 bo->bcm_proc_read = NULL; 1398 1399 INIT_LIST_HEAD(&bo->tx_ops); 1400 INIT_LIST_HEAD(&bo->rx_ops); 1401 1402 /* set notifier */ 1403 bo->notifier.notifier_call = bcm_notifier; 1404 1405 register_netdevice_notifier(&bo->notifier); 1406 1407 return 0; 1408 } 1409 1410 /* 1411 * standard socket functions 1412 */ 1413 static int bcm_release(struct socket *sock) 1414 { 1415 struct sock *sk = sock->sk; 1416 struct bcm_sock *bo = bcm_sk(sk); 1417 struct bcm_op *op, *next; 1418 1419 /* remove bcm_ops, timer, rx_unregister(), etc. */ 1420 1421 unregister_netdevice_notifier(&bo->notifier); 1422 1423 lock_sock(sk); 1424 1425 list_for_each_entry_safe(op, next, &bo->tx_ops, list) 1426 bcm_remove_op(op); 1427 1428 list_for_each_entry_safe(op, next, &bo->rx_ops, list) { 1429 /* 1430 * Don't care if we're bound or not (due to netdev problems) 1431 * can_rx_unregister() is always a save thing to do here. 1432 */ 1433 if (op->ifindex) { 1434 /* 1435 * Only remove subscriptions that had not 1436 * been removed due to NETDEV_UNREGISTER 1437 * in bcm_notifier() 1438 */ 1439 if (op->rx_reg_dev) { 1440 struct net_device *dev; 1441 1442 dev = dev_get_by_index(&init_net, op->ifindex); 1443 if (dev) { 1444 bcm_rx_unreg(dev, op); 1445 dev_put(dev); 1446 } 1447 } 1448 } else 1449 can_rx_unregister(NULL, op->can_id, 1450 REGMASK(op->can_id), 1451 bcm_rx_handler, op); 1452 1453 bcm_remove_op(op); 1454 } 1455 1456 /* remove procfs entry */ 1457 if (proc_dir && bo->bcm_proc_read) 1458 remove_proc_entry(bo->procname, proc_dir); 1459 1460 /* remove device reference */ 1461 if (bo->bound) { 1462 bo->bound = 0; 1463 bo->ifindex = 0; 1464 } 1465 1466 sock_orphan(sk); 1467 sock->sk = NULL; 1468 1469 release_sock(sk); 1470 sock_put(sk); 1471 1472 return 0; 1473 } 1474 1475 static int bcm_connect(struct socket *sock, struct sockaddr *uaddr, int len, 1476 int flags) 1477 { 1478 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; 1479 struct sock *sk = sock->sk; 1480 struct bcm_sock *bo = bcm_sk(sk); 1481 1482 if (len < sizeof(*addr)) 1483 return -EINVAL; 1484 1485 if (bo->bound) 1486 return -EISCONN; 1487 1488 /* bind a device to this socket */ 1489 if (addr->can_ifindex) { 1490 struct net_device *dev; 1491 1492 dev = dev_get_by_index(&init_net, addr->can_ifindex); 1493 if (!dev) 1494 return -ENODEV; 1495 1496 if (dev->type != ARPHRD_CAN) { 1497 dev_put(dev); 1498 return -ENODEV; 1499 } 1500 1501 bo->ifindex = dev->ifindex; 1502 dev_put(dev); 1503 1504 } else { 1505 /* no interface reference for ifindex = 0 ('any' CAN device) */ 1506 bo->ifindex = 0; 1507 } 1508 1509 bo->bound = 1; 1510 1511 if (proc_dir) { 1512 /* unique socket address as filename */ 1513 sprintf(bo->procname, "%p", sock); 1514 bo->bcm_proc_read = proc_create_data(bo->procname, 0644, 1515 proc_dir, 1516 &bcm_proc_fops, sk); 1517 } 1518 1519 return 0; 1520 } 1521 1522 static int bcm_recvmsg(struct kiocb *iocb, struct socket *sock, 1523 struct msghdr *msg, size_t size, int flags) 1524 { 1525 struct sock *sk = sock->sk; 1526 struct sk_buff *skb; 1527 int error = 0; 1528 int noblock; 1529 int err; 1530 1531 noblock = flags & MSG_DONTWAIT; 1532 flags &= ~MSG_DONTWAIT; 1533 skb = skb_recv_datagram(sk, flags, noblock, &error); 1534 if (!skb) 1535 return error; 1536 1537 if (skb->len < size) 1538 size = skb->len; 1539 1540 err = memcpy_toiovec(msg->msg_iov, skb->data, size); 1541 if (err < 0) { 1542 skb_free_datagram(sk, skb); 1543 return err; 1544 } 1545 1546 sock_recv_ts_and_drops(msg, sk, skb); 1547 1548 if (msg->msg_name) { 1549 msg->msg_namelen = sizeof(struct sockaddr_can); 1550 memcpy(msg->msg_name, skb->cb, msg->msg_namelen); 1551 } 1552 1553 skb_free_datagram(sk, skb); 1554 1555 return size; 1556 } 1557 1558 static struct proto_ops bcm_ops __read_mostly = { 1559 .family = PF_CAN, 1560 .release = bcm_release, 1561 .bind = sock_no_bind, 1562 .connect = bcm_connect, 1563 .socketpair = sock_no_socketpair, 1564 .accept = sock_no_accept, 1565 .getname = sock_no_getname, 1566 .poll = datagram_poll, 1567 .ioctl = NULL, /* use can_ioctl() from af_can.c */ 1568 .listen = sock_no_listen, 1569 .shutdown = sock_no_shutdown, 1570 .setsockopt = sock_no_setsockopt, 1571 .getsockopt = sock_no_getsockopt, 1572 .sendmsg = bcm_sendmsg, 1573 .recvmsg = bcm_recvmsg, 1574 .mmap = sock_no_mmap, 1575 .sendpage = sock_no_sendpage, 1576 }; 1577 1578 static struct proto bcm_proto __read_mostly = { 1579 .name = "CAN_BCM", 1580 .owner = THIS_MODULE, 1581 .obj_size = sizeof(struct bcm_sock), 1582 .init = bcm_init, 1583 }; 1584 1585 static struct can_proto bcm_can_proto __read_mostly = { 1586 .type = SOCK_DGRAM, 1587 .protocol = CAN_BCM, 1588 .ops = &bcm_ops, 1589 .prot = &bcm_proto, 1590 }; 1591 1592 static int __init bcm_module_init(void) 1593 { 1594 int err; 1595 1596 printk(banner); 1597 1598 err = can_proto_register(&bcm_can_proto); 1599 if (err < 0) { 1600 printk(KERN_ERR "can: registration of bcm protocol failed\n"); 1601 return err; 1602 } 1603 1604 /* create /proc/net/can-bcm directory */ 1605 proc_dir = proc_mkdir("can-bcm", init_net.proc_net); 1606 return 0; 1607 } 1608 1609 static void __exit bcm_module_exit(void) 1610 { 1611 can_proto_unregister(&bcm_can_proto); 1612 1613 if (proc_dir) 1614 proc_net_remove(&init_net, "can-bcm"); 1615 } 1616 1617 module_init(bcm_module_init); 1618 module_exit(bcm_module_exit); 1619