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/uio.h> 50 #include <linux/net.h> 51 #include <linux/netdevice.h> 52 #include <linux/socket.h> 53 #include <linux/if_arp.h> 54 #include <linux/skbuff.h> 55 #include <linux/can.h> 56 #include <linux/can/core.h> 57 #include <linux/can/bcm.h> 58 #include <net/sock.h> 59 #include <net/net_namespace.h> 60 61 /* use of last_frames[index].can_dlc */ 62 #define RX_RECV 0x40 /* received data for this element */ 63 #define RX_THR 0x80 /* element not been sent due to throttle feature */ 64 #define BCM_CAN_DLC_MASK 0x0F /* clean private flags in can_dlc by masking */ 65 66 /* get best masking value for can_rx_register() for a given single can_id */ 67 #define REGMASK(id) ((id & CAN_RTR_FLAG) | ((id & CAN_EFF_FLAG) ? \ 68 (CAN_EFF_MASK | CAN_EFF_FLAG) : CAN_SFF_MASK)) 69 70 #define CAN_BCM_VERSION "20080415" 71 static __initdata const char banner[] = KERN_INFO 72 "can: broadcast manager protocol (rev " CAN_BCM_VERSION ")\n"; 73 74 MODULE_DESCRIPTION("PF_CAN broadcast manager protocol"); 75 MODULE_LICENSE("Dual BSD/GPL"); 76 MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>"); 77 78 /* easy access to can_frame payload */ 79 static inline u64 GET_U64(const struct can_frame *cp) 80 { 81 return *(u64 *)cp->data; 82 } 83 84 struct bcm_op { 85 struct list_head list; 86 int ifindex; 87 canid_t can_id; 88 int flags; 89 unsigned long frames_abs, frames_filtered; 90 struct timeval ival1, ival2; 91 struct hrtimer timer, thrtimer; 92 ktime_t rx_stamp, kt_ival1, kt_ival2, kt_lastmsg; 93 int rx_ifindex; 94 int count; 95 int nframes; 96 int currframe; 97 struct can_frame *frames; 98 struct can_frame *last_frames; 99 struct can_frame sframe; 100 struct can_frame last_sframe; 101 struct sock *sk; 102 struct net_device *rx_reg_dev; 103 }; 104 105 static struct proc_dir_entry *proc_dir; 106 107 struct bcm_sock { 108 struct sock sk; 109 int bound; 110 int ifindex; 111 struct notifier_block notifier; 112 struct list_head rx_ops; 113 struct list_head tx_ops; 114 unsigned long dropped_usr_msgs; 115 struct proc_dir_entry *bcm_proc_read; 116 char procname [9]; /* pointer printed in ASCII with \0 */ 117 }; 118 119 static inline struct bcm_sock *bcm_sk(const struct sock *sk) 120 { 121 return (struct bcm_sock *)sk; 122 } 123 124 #define CFSIZ sizeof(struct can_frame) 125 #define OPSIZ sizeof(struct bcm_op) 126 #define MHSIZ sizeof(struct bcm_msg_head) 127 128 /* 129 * procfs functions 130 */ 131 static char *bcm_proc_getifname(int ifindex) 132 { 133 struct net_device *dev; 134 135 if (!ifindex) 136 return "any"; 137 138 /* no usage counting */ 139 dev = __dev_get_by_index(&init_net, ifindex); 140 if (dev) 141 return dev->name; 142 143 return "???"; 144 } 145 146 static int bcm_read_proc(char *page, char **start, off_t off, 147 int count, int *eof, void *data) 148 { 149 int len = 0; 150 struct sock *sk = (struct sock *)data; 151 struct bcm_sock *bo = bcm_sk(sk); 152 struct bcm_op *op; 153 154 len += snprintf(page + len, PAGE_SIZE - len, ">>> socket %p", 155 sk->sk_socket); 156 len += snprintf(page + len, PAGE_SIZE - len, " / sk %p", sk); 157 len += snprintf(page + len, PAGE_SIZE - len, " / bo %p", bo); 158 len += snprintf(page + len, PAGE_SIZE - len, " / dropped %lu", 159 bo->dropped_usr_msgs); 160 len += snprintf(page + len, PAGE_SIZE - len, " / bound %s", 161 bcm_proc_getifname(bo->ifindex)); 162 len += snprintf(page + len, PAGE_SIZE - len, " <<<\n"); 163 164 list_for_each_entry(op, &bo->rx_ops, list) { 165 166 unsigned long reduction; 167 168 /* print only active entries & prevent division by zero */ 169 if (!op->frames_abs) 170 continue; 171 172 len += snprintf(page + len, PAGE_SIZE - len, 173 "rx_op: %03X %-5s ", 174 op->can_id, bcm_proc_getifname(op->ifindex)); 175 len += snprintf(page + len, PAGE_SIZE - len, "[%d]%c ", 176 op->nframes, 177 (op->flags & RX_CHECK_DLC)?'d':' '); 178 if (op->kt_ival1.tv64) 179 len += snprintf(page + len, PAGE_SIZE - len, 180 "timeo=%lld ", 181 (long long) 182 ktime_to_us(op->kt_ival1)); 183 184 if (op->kt_ival2.tv64) 185 len += snprintf(page + len, PAGE_SIZE - len, 186 "thr=%lld ", 187 (long long) 188 ktime_to_us(op->kt_ival2)); 189 190 len += snprintf(page + len, PAGE_SIZE - len, 191 "# recv %ld (%ld) => reduction: ", 192 op->frames_filtered, op->frames_abs); 193 194 reduction = 100 - (op->frames_filtered * 100) / op->frames_abs; 195 196 len += snprintf(page + len, PAGE_SIZE - len, "%s%ld%%\n", 197 (reduction == 100)?"near ":"", reduction); 198 199 if (len > PAGE_SIZE - 200) { 200 /* mark output cut off */ 201 len += snprintf(page + len, PAGE_SIZE - len, "(..)\n"); 202 break; 203 } 204 } 205 206 list_for_each_entry(op, &bo->tx_ops, list) { 207 208 len += snprintf(page + len, PAGE_SIZE - len, 209 "tx_op: %03X %s [%d] ", 210 op->can_id, bcm_proc_getifname(op->ifindex), 211 op->nframes); 212 213 if (op->kt_ival1.tv64) 214 len += snprintf(page + len, PAGE_SIZE - len, "t1=%lld ", 215 (long long) ktime_to_us(op->kt_ival1)); 216 217 if (op->kt_ival2.tv64) 218 len += snprintf(page + len, PAGE_SIZE - len, "t2=%lld ", 219 (long long) ktime_to_us(op->kt_ival2)); 220 221 len += snprintf(page + len, PAGE_SIZE - len, "# sent %ld\n", 222 op->frames_abs); 223 224 if (len > PAGE_SIZE - 100) { 225 /* mark output cut off */ 226 len += snprintf(page + len, PAGE_SIZE - len, "(..)\n"); 227 break; 228 } 229 } 230 231 len += snprintf(page + len, PAGE_SIZE - len, "\n"); 232 233 *eof = 1; 234 return len; 235 } 236 237 /* 238 * bcm_can_tx - send the (next) CAN frame to the appropriate CAN interface 239 * of the given bcm tx op 240 */ 241 static void bcm_can_tx(struct bcm_op *op) 242 { 243 struct sk_buff *skb; 244 struct net_device *dev; 245 struct can_frame *cf = &op->frames[op->currframe]; 246 247 /* no target device? => exit */ 248 if (!op->ifindex) 249 return; 250 251 dev = dev_get_by_index(&init_net, op->ifindex); 252 if (!dev) { 253 /* RFC: should this bcm_op remove itself here? */ 254 return; 255 } 256 257 skb = alloc_skb(CFSIZ, gfp_any()); 258 if (!skb) 259 goto out; 260 261 memcpy(skb_put(skb, CFSIZ), cf, CFSIZ); 262 263 /* send with loopback */ 264 skb->dev = dev; 265 skb->sk = op->sk; 266 can_send(skb, 1); 267 268 /* update statistics */ 269 op->currframe++; 270 op->frames_abs++; 271 272 /* reached last frame? */ 273 if (op->currframe >= op->nframes) 274 op->currframe = 0; 275 out: 276 dev_put(dev); 277 } 278 279 /* 280 * bcm_send_to_user - send a BCM message to the userspace 281 * (consisting of bcm_msg_head + x CAN frames) 282 */ 283 static void bcm_send_to_user(struct bcm_op *op, struct bcm_msg_head *head, 284 struct can_frame *frames, int has_timestamp) 285 { 286 struct sk_buff *skb; 287 struct can_frame *firstframe; 288 struct sockaddr_can *addr; 289 struct sock *sk = op->sk; 290 int datalen = head->nframes * CFSIZ; 291 int err; 292 293 skb = alloc_skb(sizeof(*head) + datalen, gfp_any()); 294 if (!skb) 295 return; 296 297 memcpy(skb_put(skb, sizeof(*head)), head, sizeof(*head)); 298 299 if (head->nframes) { 300 /* can_frames starting here */ 301 firstframe = (struct can_frame *) skb_tail_pointer(skb); 302 303 memcpy(skb_put(skb, datalen), frames, datalen); 304 305 /* 306 * the BCM uses the can_dlc-element of the can_frame 307 * structure for internal purposes. This is only 308 * relevant for updates that are generated by the 309 * BCM, where nframes is 1 310 */ 311 if (head->nframes == 1) 312 firstframe->can_dlc &= BCM_CAN_DLC_MASK; 313 } 314 315 if (has_timestamp) { 316 /* restore rx timestamp */ 317 skb->tstamp = op->rx_stamp; 318 } 319 320 /* 321 * Put the datagram to the queue so that bcm_recvmsg() can 322 * get it from there. We need to pass the interface index to 323 * bcm_recvmsg(). We pass a whole struct sockaddr_can in skb->cb 324 * containing the interface index. 325 */ 326 327 BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct sockaddr_can)); 328 addr = (struct sockaddr_can *)skb->cb; 329 memset(addr, 0, sizeof(*addr)); 330 addr->can_family = AF_CAN; 331 addr->can_ifindex = op->rx_ifindex; 332 333 err = sock_queue_rcv_skb(sk, skb); 334 if (err < 0) { 335 struct bcm_sock *bo = bcm_sk(sk); 336 337 kfree_skb(skb); 338 /* don't care about overflows in this statistic */ 339 bo->dropped_usr_msgs++; 340 } 341 } 342 343 /* 344 * bcm_tx_timeout_handler - performes cyclic CAN frame transmissions 345 */ 346 static enum hrtimer_restart bcm_tx_timeout_handler(struct hrtimer *hrtimer) 347 { 348 struct bcm_op *op = container_of(hrtimer, struct bcm_op, timer); 349 enum hrtimer_restart ret = HRTIMER_NORESTART; 350 351 if (op->kt_ival1.tv64 && (op->count > 0)) { 352 353 op->count--; 354 if (!op->count && (op->flags & TX_COUNTEVT)) { 355 struct bcm_msg_head msg_head; 356 357 /* create notification to user */ 358 msg_head.opcode = TX_EXPIRED; 359 msg_head.flags = op->flags; 360 msg_head.count = op->count; 361 msg_head.ival1 = op->ival1; 362 msg_head.ival2 = op->ival2; 363 msg_head.can_id = op->can_id; 364 msg_head.nframes = 0; 365 366 bcm_send_to_user(op, &msg_head, NULL, 0); 367 } 368 } 369 370 if (op->kt_ival1.tv64 && (op->count > 0)) { 371 372 /* send (next) frame */ 373 bcm_can_tx(op); 374 hrtimer_forward(hrtimer, ktime_get(), op->kt_ival1); 375 ret = HRTIMER_RESTART; 376 377 } else { 378 if (op->kt_ival2.tv64) { 379 380 /* send (next) frame */ 381 bcm_can_tx(op); 382 hrtimer_forward(hrtimer, ktime_get(), op->kt_ival2); 383 ret = HRTIMER_RESTART; 384 } 385 } 386 387 return ret; 388 } 389 390 /* 391 * bcm_rx_changed - create a RX_CHANGED notification due to changed content 392 */ 393 static void bcm_rx_changed(struct bcm_op *op, struct can_frame *data) 394 { 395 struct bcm_msg_head head; 396 397 /* update statistics */ 398 op->frames_filtered++; 399 400 /* prevent statistics overflow */ 401 if (op->frames_filtered > ULONG_MAX/100) 402 op->frames_filtered = op->frames_abs = 0; 403 404 head.opcode = RX_CHANGED; 405 head.flags = op->flags; 406 head.count = op->count; 407 head.ival1 = op->ival1; 408 head.ival2 = op->ival2; 409 head.can_id = op->can_id; 410 head.nframes = 1; 411 412 bcm_send_to_user(op, &head, data, 1); 413 } 414 415 /* 416 * bcm_rx_update_and_send - process a detected relevant receive content change 417 * 1. update the last received data 418 * 2. send a notification to the user (if possible) 419 */ 420 static void bcm_rx_update_and_send(struct bcm_op *op, 421 struct can_frame *lastdata, 422 struct can_frame *rxdata) 423 { 424 memcpy(lastdata, rxdata, CFSIZ); 425 426 /* mark as used */ 427 lastdata->can_dlc |= RX_RECV; 428 429 /* throtteling mode inactive OR data update already on the run ? */ 430 if (!op->kt_ival2.tv64 || hrtimer_callback_running(&op->thrtimer)) { 431 /* send RX_CHANGED to the user immediately */ 432 bcm_rx_changed(op, rxdata); 433 return; 434 } 435 436 if (hrtimer_active(&op->thrtimer)) { 437 /* mark as 'throttled' */ 438 lastdata->can_dlc |= RX_THR; 439 return; 440 } 441 442 if (!op->kt_lastmsg.tv64) { 443 /* send first RX_CHANGED to the user immediately */ 444 bcm_rx_changed(op, rxdata); 445 op->kt_lastmsg = ktime_get(); 446 return; 447 } 448 449 if (ktime_us_delta(ktime_get(), op->kt_lastmsg) < 450 ktime_to_us(op->kt_ival2)) { 451 /* mark as 'throttled' and start timer */ 452 lastdata->can_dlc |= RX_THR; 453 hrtimer_start(&op->thrtimer, 454 ktime_add(op->kt_lastmsg, op->kt_ival2), 455 HRTIMER_MODE_ABS); 456 return; 457 } 458 459 /* the gap was that big, that throttling was not needed here */ 460 bcm_rx_changed(op, rxdata); 461 op->kt_lastmsg = ktime_get(); 462 } 463 464 /* 465 * bcm_rx_cmp_to_index - (bit)compares the currently received data to formerly 466 * received data stored in op->last_frames[] 467 */ 468 static void bcm_rx_cmp_to_index(struct bcm_op *op, int index, 469 struct can_frame *rxdata) 470 { 471 /* 472 * no one uses the MSBs of can_dlc for comparation, 473 * so we use it here to detect the first time of reception 474 */ 475 476 if (!(op->last_frames[index].can_dlc & RX_RECV)) { 477 /* received data for the first time => send update to user */ 478 bcm_rx_update_and_send(op, &op->last_frames[index], rxdata); 479 return; 480 } 481 482 /* do a real check in can_frame data section */ 483 484 if ((GET_U64(&op->frames[index]) & GET_U64(rxdata)) != 485 (GET_U64(&op->frames[index]) & GET_U64(&op->last_frames[index]))) { 486 bcm_rx_update_and_send(op, &op->last_frames[index], rxdata); 487 return; 488 } 489 490 if (op->flags & RX_CHECK_DLC) { 491 /* do a real check in can_frame dlc */ 492 if (rxdata->can_dlc != (op->last_frames[index].can_dlc & 493 BCM_CAN_DLC_MASK)) { 494 bcm_rx_update_and_send(op, &op->last_frames[index], 495 rxdata); 496 return; 497 } 498 } 499 } 500 501 /* 502 * bcm_rx_starttimer - enable timeout monitoring for CAN frame receiption 503 */ 504 static void bcm_rx_starttimer(struct bcm_op *op) 505 { 506 if (op->flags & RX_NO_AUTOTIMER) 507 return; 508 509 if (op->kt_ival1.tv64) 510 hrtimer_start(&op->timer, op->kt_ival1, HRTIMER_MODE_REL); 511 } 512 513 /* 514 * bcm_rx_timeout_handler - when the (cyclic) CAN frame receiption timed out 515 */ 516 static enum hrtimer_restart bcm_rx_timeout_handler(struct hrtimer *hrtimer) 517 { 518 struct bcm_op *op = container_of(hrtimer, struct bcm_op, timer); 519 struct bcm_msg_head msg_head; 520 521 msg_head.opcode = RX_TIMEOUT; 522 msg_head.flags = op->flags; 523 msg_head.count = op->count; 524 msg_head.ival1 = op->ival1; 525 msg_head.ival2 = op->ival2; 526 msg_head.can_id = op->can_id; 527 msg_head.nframes = 0; 528 529 bcm_send_to_user(op, &msg_head, NULL, 0); 530 531 /* no restart of the timer is done here! */ 532 533 /* if user wants to be informed, when cyclic CAN-Messages come back */ 534 if ((op->flags & RX_ANNOUNCE_RESUME) && op->last_frames) { 535 /* clear received can_frames to indicate 'nothing received' */ 536 memset(op->last_frames, 0, op->nframes * CFSIZ); 537 } 538 539 return HRTIMER_NORESTART; 540 } 541 542 /* 543 * bcm_rx_thr_flush - Check for throttled data and send it to the userspace 544 */ 545 static int bcm_rx_thr_flush(struct bcm_op *op) 546 { 547 int updated = 0; 548 549 if (op->nframes > 1) { 550 int i; 551 552 /* for MUX filter we start at index 1 */ 553 for (i = 1; i < op->nframes; i++) { 554 if ((op->last_frames) && 555 (op->last_frames[i].can_dlc & RX_THR)) { 556 op->last_frames[i].can_dlc &= ~RX_THR; 557 bcm_rx_changed(op, &op->last_frames[i]); 558 updated++; 559 } 560 } 561 562 } else { 563 /* for RX_FILTER_ID and simple filter */ 564 if (op->last_frames && (op->last_frames[0].can_dlc & RX_THR)) { 565 op->last_frames[0].can_dlc &= ~RX_THR; 566 bcm_rx_changed(op, &op->last_frames[0]); 567 updated++; 568 } 569 } 570 571 return updated; 572 } 573 574 /* 575 * bcm_rx_thr_handler - the time for blocked content updates is over now: 576 * Check for throttled data and send it to the userspace 577 */ 578 static enum hrtimer_restart bcm_rx_thr_handler(struct hrtimer *hrtimer) 579 { 580 struct bcm_op *op = container_of(hrtimer, struct bcm_op, thrtimer); 581 582 if (bcm_rx_thr_flush(op)) { 583 hrtimer_forward(hrtimer, ktime_get(), op->kt_ival2); 584 return HRTIMER_RESTART; 585 } else { 586 /* rearm throttle handling */ 587 op->kt_lastmsg = ktime_set(0, 0); 588 return HRTIMER_NORESTART; 589 } 590 } 591 592 /* 593 * bcm_rx_handler - handle a CAN frame receiption 594 */ 595 static void bcm_rx_handler(struct sk_buff *skb, void *data) 596 { 597 struct bcm_op *op = (struct bcm_op *)data; 598 struct can_frame rxframe; 599 int i; 600 601 /* disable timeout */ 602 hrtimer_cancel(&op->timer); 603 604 if (skb->len == sizeof(rxframe)) { 605 memcpy(&rxframe, skb->data, sizeof(rxframe)); 606 /* save rx timestamp */ 607 op->rx_stamp = skb->tstamp; 608 /* save originator for recvfrom() */ 609 op->rx_ifindex = skb->dev->ifindex; 610 /* update statistics */ 611 op->frames_abs++; 612 kfree_skb(skb); 613 614 } else { 615 kfree_skb(skb); 616 return; 617 } 618 619 if (op->can_id != rxframe.can_id) 620 return; 621 622 if (op->flags & RX_RTR_FRAME) { 623 /* send reply for RTR-request (placed in op->frames[0]) */ 624 bcm_can_tx(op); 625 return; 626 } 627 628 if (op->flags & RX_FILTER_ID) { 629 /* the easiest case */ 630 bcm_rx_update_and_send(op, &op->last_frames[0], &rxframe); 631 bcm_rx_starttimer(op); 632 return; 633 } 634 635 if (op->nframes == 1) { 636 /* simple compare with index 0 */ 637 bcm_rx_cmp_to_index(op, 0, &rxframe); 638 bcm_rx_starttimer(op); 639 return; 640 } 641 642 if (op->nframes > 1) { 643 /* 644 * multiplex compare 645 * 646 * find the first multiplex mask that fits. 647 * Remark: The MUX-mask is stored in index 0 648 */ 649 650 for (i = 1; i < op->nframes; i++) { 651 if ((GET_U64(&op->frames[0]) & GET_U64(&rxframe)) == 652 (GET_U64(&op->frames[0]) & 653 GET_U64(&op->frames[i]))) { 654 bcm_rx_cmp_to_index(op, i, &rxframe); 655 break; 656 } 657 } 658 bcm_rx_starttimer(op); 659 } 660 } 661 662 /* 663 * helpers for bcm_op handling: find & delete bcm [rx|tx] op elements 664 */ 665 static struct bcm_op *bcm_find_op(struct list_head *ops, canid_t can_id, 666 int ifindex) 667 { 668 struct bcm_op *op; 669 670 list_for_each_entry(op, ops, list) { 671 if ((op->can_id == can_id) && (op->ifindex == ifindex)) 672 return op; 673 } 674 675 return NULL; 676 } 677 678 static void bcm_remove_op(struct bcm_op *op) 679 { 680 hrtimer_cancel(&op->timer); 681 hrtimer_cancel(&op->thrtimer); 682 683 if ((op->frames) && (op->frames != &op->sframe)) 684 kfree(op->frames); 685 686 if ((op->last_frames) && (op->last_frames != &op->last_sframe)) 687 kfree(op->last_frames); 688 689 kfree(op); 690 691 return; 692 } 693 694 static void bcm_rx_unreg(struct net_device *dev, struct bcm_op *op) 695 { 696 if (op->rx_reg_dev == dev) { 697 can_rx_unregister(dev, op->can_id, REGMASK(op->can_id), 698 bcm_rx_handler, op); 699 700 /* mark as removed subscription */ 701 op->rx_reg_dev = NULL; 702 } else 703 printk(KERN_ERR "can-bcm: bcm_rx_unreg: registered device " 704 "mismatch %p %p\n", op->rx_reg_dev, dev); 705 } 706 707 /* 708 * bcm_delete_rx_op - find and remove a rx op (returns number of removed ops) 709 */ 710 static int bcm_delete_rx_op(struct list_head *ops, canid_t can_id, int ifindex) 711 { 712 struct bcm_op *op, *n; 713 714 list_for_each_entry_safe(op, n, ops, list) { 715 if ((op->can_id == can_id) && (op->ifindex == ifindex)) { 716 717 /* 718 * Don't care if we're bound or not (due to netdev 719 * problems) can_rx_unregister() is always a save 720 * thing to do here. 721 */ 722 if (op->ifindex) { 723 /* 724 * Only remove subscriptions that had not 725 * been removed due to NETDEV_UNREGISTER 726 * in bcm_notifier() 727 */ 728 if (op->rx_reg_dev) { 729 struct net_device *dev; 730 731 dev = dev_get_by_index(&init_net, 732 op->ifindex); 733 if (dev) { 734 bcm_rx_unreg(dev, op); 735 dev_put(dev); 736 } 737 } 738 } else 739 can_rx_unregister(NULL, op->can_id, 740 REGMASK(op->can_id), 741 bcm_rx_handler, op); 742 743 list_del(&op->list); 744 bcm_remove_op(op); 745 return 1; /* done */ 746 } 747 } 748 749 return 0; /* not found */ 750 } 751 752 /* 753 * bcm_delete_tx_op - find and remove a tx op (returns number of removed ops) 754 */ 755 static int bcm_delete_tx_op(struct list_head *ops, canid_t can_id, int ifindex) 756 { 757 struct bcm_op *op, *n; 758 759 list_for_each_entry_safe(op, n, ops, list) { 760 if ((op->can_id == can_id) && (op->ifindex == ifindex)) { 761 list_del(&op->list); 762 bcm_remove_op(op); 763 return 1; /* done */ 764 } 765 } 766 767 return 0; /* not found */ 768 } 769 770 /* 771 * bcm_read_op - read out a bcm_op and send it to the user (for bcm_sendmsg) 772 */ 773 static int bcm_read_op(struct list_head *ops, struct bcm_msg_head *msg_head, 774 int ifindex) 775 { 776 struct bcm_op *op = bcm_find_op(ops, msg_head->can_id, ifindex); 777 778 if (!op) 779 return -EINVAL; 780 781 /* put current values into msg_head */ 782 msg_head->flags = op->flags; 783 msg_head->count = op->count; 784 msg_head->ival1 = op->ival1; 785 msg_head->ival2 = op->ival2; 786 msg_head->nframes = op->nframes; 787 788 bcm_send_to_user(op, msg_head, op->frames, 0); 789 790 return MHSIZ; 791 } 792 793 /* 794 * bcm_tx_setup - create or update a bcm tx op (for bcm_sendmsg) 795 */ 796 static int bcm_tx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg, 797 int ifindex, struct sock *sk) 798 { 799 struct bcm_sock *bo = bcm_sk(sk); 800 struct bcm_op *op; 801 int i, err; 802 803 /* we need a real device to send frames */ 804 if (!ifindex) 805 return -ENODEV; 806 807 /* we need at least one can_frame */ 808 if (msg_head->nframes < 1) 809 return -EINVAL; 810 811 /* check the given can_id */ 812 op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex); 813 814 if (op) { 815 /* update existing BCM operation */ 816 817 /* 818 * Do we need more space for the can_frames than currently 819 * allocated? -> This is a _really_ unusual use-case and 820 * therefore (complexity / locking) it is not supported. 821 */ 822 if (msg_head->nframes > op->nframes) 823 return -E2BIG; 824 825 /* update can_frames content */ 826 for (i = 0; i < msg_head->nframes; i++) { 827 err = memcpy_fromiovec((u8 *)&op->frames[i], 828 msg->msg_iov, CFSIZ); 829 if (err < 0) 830 return err; 831 832 if (msg_head->flags & TX_CP_CAN_ID) { 833 /* copy can_id into frame */ 834 op->frames[i].can_id = msg_head->can_id; 835 } 836 } 837 838 } else { 839 /* insert new BCM operation for the given can_id */ 840 841 op = kzalloc(OPSIZ, GFP_KERNEL); 842 if (!op) 843 return -ENOMEM; 844 845 op->can_id = msg_head->can_id; 846 847 /* create array for can_frames and copy the data */ 848 if (msg_head->nframes > 1) { 849 op->frames = kmalloc(msg_head->nframes * CFSIZ, 850 GFP_KERNEL); 851 if (!op->frames) { 852 kfree(op); 853 return -ENOMEM; 854 } 855 } else 856 op->frames = &op->sframe; 857 858 for (i = 0; i < msg_head->nframes; i++) { 859 err = memcpy_fromiovec((u8 *)&op->frames[i], 860 msg->msg_iov, CFSIZ); 861 if (err < 0) { 862 if (op->frames != &op->sframe) 863 kfree(op->frames); 864 kfree(op); 865 return err; 866 } 867 868 if (msg_head->flags & TX_CP_CAN_ID) { 869 /* copy can_id into frame */ 870 op->frames[i].can_id = msg_head->can_id; 871 } 872 } 873 874 /* tx_ops never compare with previous received messages */ 875 op->last_frames = NULL; 876 877 /* bcm_can_tx / bcm_tx_timeout_handler needs this */ 878 op->sk = sk; 879 op->ifindex = ifindex; 880 881 /* initialize uninitialized (kzalloc) structure */ 882 hrtimer_init(&op->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); 883 op->timer.function = bcm_tx_timeout_handler; 884 885 /* currently unused in tx_ops */ 886 hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); 887 888 /* add this bcm_op to the list of the tx_ops */ 889 list_add(&op->list, &bo->tx_ops); 890 891 } /* if ((op = bcm_find_op(&bo->tx_ops, msg_head->can_id, ifindex))) */ 892 893 if (op->nframes != msg_head->nframes) { 894 op->nframes = msg_head->nframes; 895 /* start multiple frame transmission with index 0 */ 896 op->currframe = 0; 897 } 898 899 /* check flags */ 900 901 op->flags = msg_head->flags; 902 903 if (op->flags & TX_RESET_MULTI_IDX) { 904 /* start multiple frame transmission with index 0 */ 905 op->currframe = 0; 906 } 907 908 if (op->flags & SETTIMER) { 909 /* set timer values */ 910 op->count = msg_head->count; 911 op->ival1 = msg_head->ival1; 912 op->ival2 = msg_head->ival2; 913 op->kt_ival1 = timeval_to_ktime(msg_head->ival1); 914 op->kt_ival2 = timeval_to_ktime(msg_head->ival2); 915 916 /* disable an active timer due to zero values? */ 917 if (!op->kt_ival1.tv64 && !op->kt_ival2.tv64) 918 hrtimer_cancel(&op->timer); 919 } 920 921 if ((op->flags & STARTTIMER) && 922 ((op->kt_ival1.tv64 && op->count) || op->kt_ival2.tv64)) { 923 924 /* spec: send can_frame when starting timer */ 925 op->flags |= TX_ANNOUNCE; 926 927 if (op->kt_ival1.tv64 && (op->count > 0)) { 928 /* op->count-- is done in bcm_tx_timeout_handler */ 929 hrtimer_start(&op->timer, op->kt_ival1, 930 HRTIMER_MODE_REL); 931 } else 932 hrtimer_start(&op->timer, op->kt_ival2, 933 HRTIMER_MODE_REL); 934 } 935 936 if (op->flags & TX_ANNOUNCE) 937 bcm_can_tx(op); 938 939 return msg_head->nframes * CFSIZ + MHSIZ; 940 } 941 942 /* 943 * bcm_rx_setup - create or update a bcm rx op (for bcm_sendmsg) 944 */ 945 static int bcm_rx_setup(struct bcm_msg_head *msg_head, struct msghdr *msg, 946 int ifindex, struct sock *sk) 947 { 948 struct bcm_sock *bo = bcm_sk(sk); 949 struct bcm_op *op; 950 int do_rx_register; 951 int err = 0; 952 953 if ((msg_head->flags & RX_FILTER_ID) || (!(msg_head->nframes))) { 954 /* be robust against wrong usage ... */ 955 msg_head->flags |= RX_FILTER_ID; 956 /* ignore trailing garbage */ 957 msg_head->nframes = 0; 958 } 959 960 if ((msg_head->flags & RX_RTR_FRAME) && 961 ((msg_head->nframes != 1) || 962 (!(msg_head->can_id & CAN_RTR_FLAG)))) 963 return -EINVAL; 964 965 /* check the given can_id */ 966 op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex); 967 if (op) { 968 /* update existing BCM operation */ 969 970 /* 971 * Do we need more space for the can_frames than currently 972 * allocated? -> This is a _really_ unusual use-case and 973 * therefore (complexity / locking) it is not supported. 974 */ 975 if (msg_head->nframes > op->nframes) 976 return -E2BIG; 977 978 if (msg_head->nframes) { 979 /* update can_frames content */ 980 err = memcpy_fromiovec((u8 *)op->frames, 981 msg->msg_iov, 982 msg_head->nframes * CFSIZ); 983 if (err < 0) 984 return err; 985 986 /* clear last_frames to indicate 'nothing received' */ 987 memset(op->last_frames, 0, msg_head->nframes * CFSIZ); 988 } 989 990 op->nframes = msg_head->nframes; 991 992 /* Only an update -> do not call can_rx_register() */ 993 do_rx_register = 0; 994 995 } else { 996 /* insert new BCM operation for the given can_id */ 997 op = kzalloc(OPSIZ, GFP_KERNEL); 998 if (!op) 999 return -ENOMEM; 1000 1001 op->can_id = msg_head->can_id; 1002 op->nframes = msg_head->nframes; 1003 1004 if (msg_head->nframes > 1) { 1005 /* create array for can_frames and copy the data */ 1006 op->frames = kmalloc(msg_head->nframes * CFSIZ, 1007 GFP_KERNEL); 1008 if (!op->frames) { 1009 kfree(op); 1010 return -ENOMEM; 1011 } 1012 1013 /* create and init array for received can_frames */ 1014 op->last_frames = kzalloc(msg_head->nframes * CFSIZ, 1015 GFP_KERNEL); 1016 if (!op->last_frames) { 1017 kfree(op->frames); 1018 kfree(op); 1019 return -ENOMEM; 1020 } 1021 1022 } else { 1023 op->frames = &op->sframe; 1024 op->last_frames = &op->last_sframe; 1025 } 1026 1027 if (msg_head->nframes) { 1028 err = memcpy_fromiovec((u8 *)op->frames, msg->msg_iov, 1029 msg_head->nframes * CFSIZ); 1030 if (err < 0) { 1031 if (op->frames != &op->sframe) 1032 kfree(op->frames); 1033 if (op->last_frames != &op->last_sframe) 1034 kfree(op->last_frames); 1035 kfree(op); 1036 return err; 1037 } 1038 } 1039 1040 /* bcm_can_tx / bcm_tx_timeout_handler needs this */ 1041 op->sk = sk; 1042 op->ifindex = ifindex; 1043 1044 /* initialize uninitialized (kzalloc) structure */ 1045 hrtimer_init(&op->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); 1046 op->timer.function = bcm_rx_timeout_handler; 1047 1048 hrtimer_init(&op->thrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); 1049 op->thrtimer.function = bcm_rx_thr_handler; 1050 1051 /* add this bcm_op to the list of the rx_ops */ 1052 list_add(&op->list, &bo->rx_ops); 1053 1054 /* call can_rx_register() */ 1055 do_rx_register = 1; 1056 1057 } /* if ((op = bcm_find_op(&bo->rx_ops, msg_head->can_id, ifindex))) */ 1058 1059 /* check flags */ 1060 op->flags = msg_head->flags; 1061 1062 if (op->flags & RX_RTR_FRAME) { 1063 1064 /* no timers in RTR-mode */ 1065 hrtimer_cancel(&op->thrtimer); 1066 hrtimer_cancel(&op->timer); 1067 1068 /* 1069 * funny feature in RX(!)_SETUP only for RTR-mode: 1070 * copy can_id into frame BUT without RTR-flag to 1071 * prevent a full-load-loopback-test ... ;-] 1072 */ 1073 if ((op->flags & TX_CP_CAN_ID) || 1074 (op->frames[0].can_id == op->can_id)) 1075 op->frames[0].can_id = op->can_id & ~CAN_RTR_FLAG; 1076 1077 } else { 1078 if (op->flags & SETTIMER) { 1079 1080 /* set timer value */ 1081 op->ival1 = msg_head->ival1; 1082 op->ival2 = msg_head->ival2; 1083 op->kt_ival1 = timeval_to_ktime(msg_head->ival1); 1084 op->kt_ival2 = timeval_to_ktime(msg_head->ival2); 1085 1086 /* disable an active timer due to zero value? */ 1087 if (!op->kt_ival1.tv64) 1088 hrtimer_cancel(&op->timer); 1089 1090 /* 1091 * In any case cancel the throttle timer, flush 1092 * potentially blocked msgs and reset throttle handling 1093 */ 1094 op->kt_lastmsg = ktime_set(0, 0); 1095 hrtimer_cancel(&op->thrtimer); 1096 bcm_rx_thr_flush(op); 1097 } 1098 1099 if ((op->flags & STARTTIMER) && op->kt_ival1.tv64) 1100 hrtimer_start(&op->timer, op->kt_ival1, 1101 HRTIMER_MODE_REL); 1102 } 1103 1104 /* now we can register for can_ids, if we added a new bcm_op */ 1105 if (do_rx_register) { 1106 if (ifindex) { 1107 struct net_device *dev; 1108 1109 dev = dev_get_by_index(&init_net, ifindex); 1110 if (dev) { 1111 err = can_rx_register(dev, op->can_id, 1112 REGMASK(op->can_id), 1113 bcm_rx_handler, op, 1114 "bcm"); 1115 1116 op->rx_reg_dev = dev; 1117 dev_put(dev); 1118 } 1119 1120 } else 1121 err = can_rx_register(NULL, op->can_id, 1122 REGMASK(op->can_id), 1123 bcm_rx_handler, op, "bcm"); 1124 if (err) { 1125 /* this bcm rx op is broken -> remove it */ 1126 list_del(&op->list); 1127 bcm_remove_op(op); 1128 return err; 1129 } 1130 } 1131 1132 return msg_head->nframes * CFSIZ + MHSIZ; 1133 } 1134 1135 /* 1136 * bcm_tx_send - send a single CAN frame to the CAN interface (for bcm_sendmsg) 1137 */ 1138 static int bcm_tx_send(struct msghdr *msg, int ifindex, struct sock *sk) 1139 { 1140 struct sk_buff *skb; 1141 struct net_device *dev; 1142 int err; 1143 1144 /* we need a real device to send frames */ 1145 if (!ifindex) 1146 return -ENODEV; 1147 1148 skb = alloc_skb(CFSIZ, GFP_KERNEL); 1149 1150 if (!skb) 1151 return -ENOMEM; 1152 1153 err = memcpy_fromiovec(skb_put(skb, CFSIZ), msg->msg_iov, CFSIZ); 1154 if (err < 0) { 1155 kfree_skb(skb); 1156 return err; 1157 } 1158 1159 dev = dev_get_by_index(&init_net, ifindex); 1160 if (!dev) { 1161 kfree_skb(skb); 1162 return -ENODEV; 1163 } 1164 1165 skb->dev = dev; 1166 skb->sk = sk; 1167 can_send(skb, 1); /* send with loopback */ 1168 dev_put(dev); 1169 1170 return CFSIZ + MHSIZ; 1171 } 1172 1173 /* 1174 * bcm_sendmsg - process BCM commands (opcodes) from the userspace 1175 */ 1176 static int bcm_sendmsg(struct kiocb *iocb, struct socket *sock, 1177 struct msghdr *msg, size_t size) 1178 { 1179 struct sock *sk = sock->sk; 1180 struct bcm_sock *bo = bcm_sk(sk); 1181 int ifindex = bo->ifindex; /* default ifindex for this bcm_op */ 1182 struct bcm_msg_head msg_head; 1183 int ret; /* read bytes or error codes as return value */ 1184 1185 if (!bo->bound) 1186 return -ENOTCONN; 1187 1188 /* check for alternative ifindex for this bcm_op */ 1189 1190 if (!ifindex && msg->msg_name) { 1191 /* no bound device as default => check msg_name */ 1192 struct sockaddr_can *addr = 1193 (struct sockaddr_can *)msg->msg_name; 1194 1195 if (addr->can_family != AF_CAN) 1196 return -EINVAL; 1197 1198 /* ifindex from sendto() */ 1199 ifindex = addr->can_ifindex; 1200 1201 if (ifindex) { 1202 struct net_device *dev; 1203 1204 dev = dev_get_by_index(&init_net, ifindex); 1205 if (!dev) 1206 return -ENODEV; 1207 1208 if (dev->type != ARPHRD_CAN) { 1209 dev_put(dev); 1210 return -ENODEV; 1211 } 1212 1213 dev_put(dev); 1214 } 1215 } 1216 1217 /* read message head information */ 1218 1219 ret = memcpy_fromiovec((u8 *)&msg_head, msg->msg_iov, MHSIZ); 1220 if (ret < 0) 1221 return ret; 1222 1223 lock_sock(sk); 1224 1225 switch (msg_head.opcode) { 1226 1227 case TX_SETUP: 1228 ret = bcm_tx_setup(&msg_head, msg, ifindex, sk); 1229 break; 1230 1231 case RX_SETUP: 1232 ret = bcm_rx_setup(&msg_head, msg, ifindex, sk); 1233 break; 1234 1235 case TX_DELETE: 1236 if (bcm_delete_tx_op(&bo->tx_ops, msg_head.can_id, ifindex)) 1237 ret = MHSIZ; 1238 else 1239 ret = -EINVAL; 1240 break; 1241 1242 case RX_DELETE: 1243 if (bcm_delete_rx_op(&bo->rx_ops, msg_head.can_id, ifindex)) 1244 ret = MHSIZ; 1245 else 1246 ret = -EINVAL; 1247 break; 1248 1249 case TX_READ: 1250 /* reuse msg_head for the reply to TX_READ */ 1251 msg_head.opcode = TX_STATUS; 1252 ret = bcm_read_op(&bo->tx_ops, &msg_head, ifindex); 1253 break; 1254 1255 case RX_READ: 1256 /* reuse msg_head for the reply to RX_READ */ 1257 msg_head.opcode = RX_STATUS; 1258 ret = bcm_read_op(&bo->rx_ops, &msg_head, ifindex); 1259 break; 1260 1261 case TX_SEND: 1262 /* we need at least one can_frame */ 1263 if (msg_head.nframes < 1) 1264 ret = -EINVAL; 1265 else 1266 ret = bcm_tx_send(msg, ifindex, sk); 1267 break; 1268 1269 default: 1270 ret = -EINVAL; 1271 break; 1272 } 1273 1274 release_sock(sk); 1275 1276 return ret; 1277 } 1278 1279 /* 1280 * notification handler for netdevice status changes 1281 */ 1282 static int bcm_notifier(struct notifier_block *nb, unsigned long msg, 1283 void *data) 1284 { 1285 struct net_device *dev = (struct net_device *)data; 1286 struct bcm_sock *bo = container_of(nb, struct bcm_sock, notifier); 1287 struct sock *sk = &bo->sk; 1288 struct bcm_op *op; 1289 int notify_enodev = 0; 1290 1291 if (dev_net(dev) != &init_net) 1292 return NOTIFY_DONE; 1293 1294 if (dev->type != ARPHRD_CAN) 1295 return NOTIFY_DONE; 1296 1297 switch (msg) { 1298 1299 case NETDEV_UNREGISTER: 1300 lock_sock(sk); 1301 1302 /* remove device specific receive entries */ 1303 list_for_each_entry(op, &bo->rx_ops, list) 1304 if (op->rx_reg_dev == dev) 1305 bcm_rx_unreg(dev, op); 1306 1307 /* remove device reference, if this is our bound device */ 1308 if (bo->bound && bo->ifindex == dev->ifindex) { 1309 bo->bound = 0; 1310 bo->ifindex = 0; 1311 notify_enodev = 1; 1312 } 1313 1314 release_sock(sk); 1315 1316 if (notify_enodev) { 1317 sk->sk_err = ENODEV; 1318 if (!sock_flag(sk, SOCK_DEAD)) 1319 sk->sk_error_report(sk); 1320 } 1321 break; 1322 1323 case NETDEV_DOWN: 1324 if (bo->bound && bo->ifindex == dev->ifindex) { 1325 sk->sk_err = ENETDOWN; 1326 if (!sock_flag(sk, SOCK_DEAD)) 1327 sk->sk_error_report(sk); 1328 } 1329 } 1330 1331 return NOTIFY_DONE; 1332 } 1333 1334 /* 1335 * initial settings for all BCM sockets to be set at socket creation time 1336 */ 1337 static int bcm_init(struct sock *sk) 1338 { 1339 struct bcm_sock *bo = bcm_sk(sk); 1340 1341 bo->bound = 0; 1342 bo->ifindex = 0; 1343 bo->dropped_usr_msgs = 0; 1344 bo->bcm_proc_read = NULL; 1345 1346 INIT_LIST_HEAD(&bo->tx_ops); 1347 INIT_LIST_HEAD(&bo->rx_ops); 1348 1349 /* set notifier */ 1350 bo->notifier.notifier_call = bcm_notifier; 1351 1352 register_netdevice_notifier(&bo->notifier); 1353 1354 return 0; 1355 } 1356 1357 /* 1358 * standard socket functions 1359 */ 1360 static int bcm_release(struct socket *sock) 1361 { 1362 struct sock *sk = sock->sk; 1363 struct bcm_sock *bo = bcm_sk(sk); 1364 struct bcm_op *op, *next; 1365 1366 /* remove bcm_ops, timer, rx_unregister(), etc. */ 1367 1368 unregister_netdevice_notifier(&bo->notifier); 1369 1370 lock_sock(sk); 1371 1372 list_for_each_entry_safe(op, next, &bo->tx_ops, list) 1373 bcm_remove_op(op); 1374 1375 list_for_each_entry_safe(op, next, &bo->rx_ops, list) { 1376 /* 1377 * Don't care if we're bound or not (due to netdev problems) 1378 * can_rx_unregister() is always a save thing to do here. 1379 */ 1380 if (op->ifindex) { 1381 /* 1382 * Only remove subscriptions that had not 1383 * been removed due to NETDEV_UNREGISTER 1384 * in bcm_notifier() 1385 */ 1386 if (op->rx_reg_dev) { 1387 struct net_device *dev; 1388 1389 dev = dev_get_by_index(&init_net, op->ifindex); 1390 if (dev) { 1391 bcm_rx_unreg(dev, op); 1392 dev_put(dev); 1393 } 1394 } 1395 } else 1396 can_rx_unregister(NULL, op->can_id, 1397 REGMASK(op->can_id), 1398 bcm_rx_handler, op); 1399 1400 bcm_remove_op(op); 1401 } 1402 1403 /* remove procfs entry */ 1404 if (proc_dir && bo->bcm_proc_read) 1405 remove_proc_entry(bo->procname, proc_dir); 1406 1407 /* remove device reference */ 1408 if (bo->bound) { 1409 bo->bound = 0; 1410 bo->ifindex = 0; 1411 } 1412 1413 release_sock(sk); 1414 sock_put(sk); 1415 1416 return 0; 1417 } 1418 1419 static int bcm_connect(struct socket *sock, struct sockaddr *uaddr, int len, 1420 int flags) 1421 { 1422 struct sockaddr_can *addr = (struct sockaddr_can *)uaddr; 1423 struct sock *sk = sock->sk; 1424 struct bcm_sock *bo = bcm_sk(sk); 1425 1426 if (bo->bound) 1427 return -EISCONN; 1428 1429 /* bind a device to this socket */ 1430 if (addr->can_ifindex) { 1431 struct net_device *dev; 1432 1433 dev = dev_get_by_index(&init_net, addr->can_ifindex); 1434 if (!dev) 1435 return -ENODEV; 1436 1437 if (dev->type != ARPHRD_CAN) { 1438 dev_put(dev); 1439 return -ENODEV; 1440 } 1441 1442 bo->ifindex = dev->ifindex; 1443 dev_put(dev); 1444 1445 } else { 1446 /* no interface reference for ifindex = 0 ('any' CAN device) */ 1447 bo->ifindex = 0; 1448 } 1449 1450 bo->bound = 1; 1451 1452 if (proc_dir) { 1453 /* unique socket address as filename */ 1454 sprintf(bo->procname, "%p", sock); 1455 bo->bcm_proc_read = create_proc_read_entry(bo->procname, 0644, 1456 proc_dir, 1457 bcm_read_proc, sk); 1458 } 1459 1460 return 0; 1461 } 1462 1463 static int bcm_recvmsg(struct kiocb *iocb, struct socket *sock, 1464 struct msghdr *msg, size_t size, int flags) 1465 { 1466 struct sock *sk = sock->sk; 1467 struct sk_buff *skb; 1468 int error = 0; 1469 int noblock; 1470 int err; 1471 1472 noblock = flags & MSG_DONTWAIT; 1473 flags &= ~MSG_DONTWAIT; 1474 skb = skb_recv_datagram(sk, flags, noblock, &error); 1475 if (!skb) 1476 return error; 1477 1478 if (skb->len < size) 1479 size = skb->len; 1480 1481 err = memcpy_toiovec(msg->msg_iov, skb->data, size); 1482 if (err < 0) { 1483 skb_free_datagram(sk, skb); 1484 return err; 1485 } 1486 1487 sock_recv_timestamp(msg, sk, skb); 1488 1489 if (msg->msg_name) { 1490 msg->msg_namelen = sizeof(struct sockaddr_can); 1491 memcpy(msg->msg_name, skb->cb, msg->msg_namelen); 1492 } 1493 1494 skb_free_datagram(sk, skb); 1495 1496 return size; 1497 } 1498 1499 static struct proto_ops bcm_ops __read_mostly = { 1500 .family = PF_CAN, 1501 .release = bcm_release, 1502 .bind = sock_no_bind, 1503 .connect = bcm_connect, 1504 .socketpair = sock_no_socketpair, 1505 .accept = sock_no_accept, 1506 .getname = sock_no_getname, 1507 .poll = datagram_poll, 1508 .ioctl = NULL, /* use can_ioctl() from af_can.c */ 1509 .listen = sock_no_listen, 1510 .shutdown = sock_no_shutdown, 1511 .setsockopt = sock_no_setsockopt, 1512 .getsockopt = sock_no_getsockopt, 1513 .sendmsg = bcm_sendmsg, 1514 .recvmsg = bcm_recvmsg, 1515 .mmap = sock_no_mmap, 1516 .sendpage = sock_no_sendpage, 1517 }; 1518 1519 static struct proto bcm_proto __read_mostly = { 1520 .name = "CAN_BCM", 1521 .owner = THIS_MODULE, 1522 .obj_size = sizeof(struct bcm_sock), 1523 .init = bcm_init, 1524 }; 1525 1526 static struct can_proto bcm_can_proto __read_mostly = { 1527 .type = SOCK_DGRAM, 1528 .protocol = CAN_BCM, 1529 .capability = -1, 1530 .ops = &bcm_ops, 1531 .prot = &bcm_proto, 1532 }; 1533 1534 static int __init bcm_module_init(void) 1535 { 1536 int err; 1537 1538 printk(banner); 1539 1540 err = can_proto_register(&bcm_can_proto); 1541 if (err < 0) { 1542 printk(KERN_ERR "can: registration of bcm protocol failed\n"); 1543 return err; 1544 } 1545 1546 /* create /proc/net/can-bcm directory */ 1547 proc_dir = proc_mkdir("can-bcm", init_net.proc_net); 1548 1549 if (proc_dir) 1550 proc_dir->owner = THIS_MODULE; 1551 1552 return 0; 1553 } 1554 1555 static void __exit bcm_module_exit(void) 1556 { 1557 can_proto_unregister(&bcm_can_proto); 1558 1559 if (proc_dir) 1560 proc_net_remove(&init_net, "can-bcm"); 1561 } 1562 1563 module_init(bcm_module_init); 1564 module_exit(bcm_module_exit); 1565