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