1 /* 2 BNEP implementation for Linux Bluetooth stack (BlueZ). 3 Copyright (C) 2001-2002 Inventel Systemes 4 Written 2001-2002 by 5 Clément Moreau <clement.moreau@inventel.fr> 6 David Libault <david.libault@inventel.fr> 7 8 Copyright (C) 2002 Maxim Krasnyansky <maxk@qualcomm.com> 9 10 This program is free software; you can redistribute it and/or modify 11 it under the terms of the GNU General Public License version 2 as 12 published by the Free Software Foundation; 13 14 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 15 OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 16 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS. 17 IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY 18 CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES 19 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 20 ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 21 OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 22 23 ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS, 24 COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS 25 SOFTWARE IS DISCLAIMED. 26 */ 27 28 #include <linux/module.h> 29 #include <linux/kthread.h> 30 #include <linux/file.h> 31 #include <linux/etherdevice.h> 32 #include <asm/unaligned.h> 33 34 #include <net/bluetooth/bluetooth.h> 35 #include <net/bluetooth/l2cap.h> 36 #include <net/bluetooth/hci_core.h> 37 38 #include "bnep.h" 39 40 #define VERSION "1.3" 41 42 static bool compress_src = true; 43 static bool compress_dst = true; 44 45 static LIST_HEAD(bnep_session_list); 46 static DECLARE_RWSEM(bnep_session_sem); 47 48 static struct bnep_session *__bnep_get_session(u8 *dst) 49 { 50 struct bnep_session *s; 51 52 BT_DBG(""); 53 54 list_for_each_entry(s, &bnep_session_list, list) 55 if (ether_addr_equal(dst, s->eh.h_source)) 56 return s; 57 58 return NULL; 59 } 60 61 static void __bnep_link_session(struct bnep_session *s) 62 { 63 list_add(&s->list, &bnep_session_list); 64 } 65 66 static void __bnep_unlink_session(struct bnep_session *s) 67 { 68 list_del(&s->list); 69 } 70 71 static int bnep_send(struct bnep_session *s, void *data, size_t len) 72 { 73 struct socket *sock = s->sock; 74 struct kvec iv = { data, len }; 75 76 return kernel_sendmsg(sock, &s->msg, &iv, 1, len); 77 } 78 79 static int bnep_send_rsp(struct bnep_session *s, u8 ctrl, u16 resp) 80 { 81 struct bnep_control_rsp rsp; 82 rsp.type = BNEP_CONTROL; 83 rsp.ctrl = ctrl; 84 rsp.resp = htons(resp); 85 return bnep_send(s, &rsp, sizeof(rsp)); 86 } 87 88 #ifdef CONFIG_BT_BNEP_PROTO_FILTER 89 static inline void bnep_set_default_proto_filter(struct bnep_session *s) 90 { 91 /* (IPv4, ARP) */ 92 s->proto_filter[0].start = ETH_P_IP; 93 s->proto_filter[0].end = ETH_P_ARP; 94 /* (RARP, AppleTalk) */ 95 s->proto_filter[1].start = ETH_P_RARP; 96 s->proto_filter[1].end = ETH_P_AARP; 97 /* (IPX, IPv6) */ 98 s->proto_filter[2].start = ETH_P_IPX; 99 s->proto_filter[2].end = ETH_P_IPV6; 100 } 101 #endif 102 103 static int bnep_ctrl_set_netfilter(struct bnep_session *s, __be16 *data, int len) 104 { 105 int n; 106 107 if (len < 2) 108 return -EILSEQ; 109 110 n = get_unaligned_be16(data); 111 data++; 112 len -= 2; 113 114 if (len < n) 115 return -EILSEQ; 116 117 BT_DBG("filter len %d", n); 118 119 #ifdef CONFIG_BT_BNEP_PROTO_FILTER 120 n /= 4; 121 if (n <= BNEP_MAX_PROTO_FILTERS) { 122 struct bnep_proto_filter *f = s->proto_filter; 123 int i; 124 125 for (i = 0; i < n; i++) { 126 f[i].start = get_unaligned_be16(data++); 127 f[i].end = get_unaligned_be16(data++); 128 129 BT_DBG("proto filter start %d end %d", 130 f[i].start, f[i].end); 131 } 132 133 if (i < BNEP_MAX_PROTO_FILTERS) 134 memset(f + i, 0, sizeof(*f)); 135 136 if (n == 0) 137 bnep_set_default_proto_filter(s); 138 139 bnep_send_rsp(s, BNEP_FILTER_NET_TYPE_RSP, BNEP_SUCCESS); 140 } else { 141 bnep_send_rsp(s, BNEP_FILTER_NET_TYPE_RSP, BNEP_FILTER_LIMIT_REACHED); 142 } 143 #else 144 bnep_send_rsp(s, BNEP_FILTER_NET_TYPE_RSP, BNEP_FILTER_UNSUPPORTED_REQ); 145 #endif 146 return 0; 147 } 148 149 static int bnep_ctrl_set_mcfilter(struct bnep_session *s, u8 *data, int len) 150 { 151 int n; 152 153 if (len < 2) 154 return -EILSEQ; 155 156 n = get_unaligned_be16(data); 157 data += 2; 158 len -= 2; 159 160 if (len < n) 161 return -EILSEQ; 162 163 BT_DBG("filter len %d", n); 164 165 #ifdef CONFIG_BT_BNEP_MC_FILTER 166 n /= (ETH_ALEN * 2); 167 168 if (n > 0) { 169 int i; 170 171 s->mc_filter = 0; 172 173 /* Always send broadcast */ 174 set_bit(bnep_mc_hash(s->dev->broadcast), (ulong *) &s->mc_filter); 175 176 /* Add address ranges to the multicast hash */ 177 for (; n > 0; n--) { 178 u8 a1[6], *a2; 179 180 memcpy(a1, data, ETH_ALEN); 181 data += ETH_ALEN; 182 a2 = data; 183 data += ETH_ALEN; 184 185 BT_DBG("mc filter %pMR -> %pMR", a1, a2); 186 187 /* Iterate from a1 to a2 */ 188 set_bit(bnep_mc_hash(a1), (ulong *) &s->mc_filter); 189 while (memcmp(a1, a2, 6) < 0 && s->mc_filter != ~0LL) { 190 /* Increment a1 */ 191 i = 5; 192 while (i >= 0 && ++a1[i--] == 0) 193 ; 194 195 set_bit(bnep_mc_hash(a1), (ulong *) &s->mc_filter); 196 } 197 } 198 } 199 200 BT_DBG("mc filter hash 0x%llx", s->mc_filter); 201 202 bnep_send_rsp(s, BNEP_FILTER_MULTI_ADDR_RSP, BNEP_SUCCESS); 203 #else 204 bnep_send_rsp(s, BNEP_FILTER_MULTI_ADDR_RSP, BNEP_FILTER_UNSUPPORTED_REQ); 205 #endif 206 return 0; 207 } 208 209 static int bnep_rx_control(struct bnep_session *s, void *data, int len) 210 { 211 u8 cmd = *(u8 *)data; 212 int err = 0; 213 214 data++; 215 len--; 216 217 switch (cmd) { 218 case BNEP_CMD_NOT_UNDERSTOOD: 219 case BNEP_SETUP_CONN_RSP: 220 case BNEP_FILTER_NET_TYPE_RSP: 221 case BNEP_FILTER_MULTI_ADDR_RSP: 222 /* Ignore these for now */ 223 break; 224 225 case BNEP_FILTER_NET_TYPE_SET: 226 err = bnep_ctrl_set_netfilter(s, data, len); 227 break; 228 229 case BNEP_FILTER_MULTI_ADDR_SET: 230 err = bnep_ctrl_set_mcfilter(s, data, len); 231 break; 232 233 case BNEP_SETUP_CONN_REQ: 234 err = bnep_send_rsp(s, BNEP_SETUP_CONN_RSP, BNEP_CONN_NOT_ALLOWED); 235 break; 236 237 default: { 238 u8 pkt[3]; 239 pkt[0] = BNEP_CONTROL; 240 pkt[1] = BNEP_CMD_NOT_UNDERSTOOD; 241 pkt[2] = cmd; 242 bnep_send(s, pkt, sizeof(pkt)); 243 } 244 break; 245 } 246 247 return err; 248 } 249 250 static int bnep_rx_extension(struct bnep_session *s, struct sk_buff *skb) 251 { 252 struct bnep_ext_hdr *h; 253 int err = 0; 254 255 do { 256 h = (void *) skb->data; 257 if (!skb_pull(skb, sizeof(*h))) { 258 err = -EILSEQ; 259 break; 260 } 261 262 BT_DBG("type 0x%x len %d", h->type, h->len); 263 264 switch (h->type & BNEP_TYPE_MASK) { 265 case BNEP_EXT_CONTROL: 266 bnep_rx_control(s, skb->data, skb->len); 267 break; 268 269 default: 270 /* Unknown extension, skip it. */ 271 break; 272 } 273 274 if (!skb_pull(skb, h->len)) { 275 err = -EILSEQ; 276 break; 277 } 278 } while (!err && (h->type & BNEP_EXT_HEADER)); 279 280 return err; 281 } 282 283 static u8 __bnep_rx_hlen[] = { 284 ETH_HLEN, /* BNEP_GENERAL */ 285 0, /* BNEP_CONTROL */ 286 2, /* BNEP_COMPRESSED */ 287 ETH_ALEN + 2, /* BNEP_COMPRESSED_SRC_ONLY */ 288 ETH_ALEN + 2 /* BNEP_COMPRESSED_DST_ONLY */ 289 }; 290 291 static int bnep_rx_frame(struct bnep_session *s, struct sk_buff *skb) 292 { 293 struct net_device *dev = s->dev; 294 struct sk_buff *nskb; 295 u8 type; 296 297 dev->stats.rx_bytes += skb->len; 298 299 type = *(u8 *) skb->data; 300 skb_pull(skb, 1); 301 302 if ((type & BNEP_TYPE_MASK) >= sizeof(__bnep_rx_hlen)) 303 goto badframe; 304 305 if ((type & BNEP_TYPE_MASK) == BNEP_CONTROL) { 306 bnep_rx_control(s, skb->data, skb->len); 307 kfree_skb(skb); 308 return 0; 309 } 310 311 skb_reset_mac_header(skb); 312 313 /* Verify and pull out header */ 314 if (!skb_pull(skb, __bnep_rx_hlen[type & BNEP_TYPE_MASK])) 315 goto badframe; 316 317 s->eh.h_proto = get_unaligned((__be16 *) (skb->data - 2)); 318 319 if (type & BNEP_EXT_HEADER) { 320 if (bnep_rx_extension(s, skb) < 0) 321 goto badframe; 322 } 323 324 /* Strip 802.1p header */ 325 if (ntohs(s->eh.h_proto) == ETH_P_8021Q) { 326 if (!skb_pull(skb, 4)) 327 goto badframe; 328 s->eh.h_proto = get_unaligned((__be16 *) (skb->data - 2)); 329 } 330 331 /* We have to alloc new skb and copy data here :(. Because original skb 332 * may not be modified and because of the alignment requirements. */ 333 nskb = alloc_skb(2 + ETH_HLEN + skb->len, GFP_KERNEL); 334 if (!nskb) { 335 dev->stats.rx_dropped++; 336 kfree_skb(skb); 337 return -ENOMEM; 338 } 339 skb_reserve(nskb, 2); 340 341 /* Decompress header and construct ether frame */ 342 switch (type & BNEP_TYPE_MASK) { 343 case BNEP_COMPRESSED: 344 memcpy(__skb_put(nskb, ETH_HLEN), &s->eh, ETH_HLEN); 345 break; 346 347 case BNEP_COMPRESSED_SRC_ONLY: 348 memcpy(__skb_put(nskb, ETH_ALEN), s->eh.h_dest, ETH_ALEN); 349 memcpy(__skb_put(nskb, ETH_ALEN), skb_mac_header(skb), ETH_ALEN); 350 put_unaligned(s->eh.h_proto, (__be16 *) __skb_put(nskb, 2)); 351 break; 352 353 case BNEP_COMPRESSED_DST_ONLY: 354 memcpy(__skb_put(nskb, ETH_ALEN), skb_mac_header(skb), 355 ETH_ALEN); 356 memcpy(__skb_put(nskb, ETH_ALEN + 2), s->eh.h_source, 357 ETH_ALEN + 2); 358 break; 359 360 case BNEP_GENERAL: 361 memcpy(__skb_put(nskb, ETH_ALEN * 2), skb_mac_header(skb), 362 ETH_ALEN * 2); 363 put_unaligned(s->eh.h_proto, (__be16 *) __skb_put(nskb, 2)); 364 break; 365 } 366 367 skb_copy_from_linear_data(skb, __skb_put(nskb, skb->len), skb->len); 368 kfree_skb(skb); 369 370 dev->stats.rx_packets++; 371 nskb->ip_summed = CHECKSUM_NONE; 372 nskb->protocol = eth_type_trans(nskb, dev); 373 netif_rx_ni(nskb); 374 return 0; 375 376 badframe: 377 dev->stats.rx_errors++; 378 kfree_skb(skb); 379 return 0; 380 } 381 382 static u8 __bnep_tx_types[] = { 383 BNEP_GENERAL, 384 BNEP_COMPRESSED_SRC_ONLY, 385 BNEP_COMPRESSED_DST_ONLY, 386 BNEP_COMPRESSED 387 }; 388 389 static int bnep_tx_frame(struct bnep_session *s, struct sk_buff *skb) 390 { 391 struct ethhdr *eh = (void *) skb->data; 392 struct socket *sock = s->sock; 393 struct kvec iv[3]; 394 int len = 0, il = 0; 395 u8 type = 0; 396 397 BT_DBG("skb %p dev %p type %d", skb, skb->dev, skb->pkt_type); 398 399 if (!skb->dev) { 400 /* Control frame sent by us */ 401 goto send; 402 } 403 404 iv[il++] = (struct kvec) { &type, 1 }; 405 len++; 406 407 if (compress_src && ether_addr_equal(eh->h_dest, s->eh.h_source)) 408 type |= 0x01; 409 410 if (compress_dst && ether_addr_equal(eh->h_source, s->eh.h_dest)) 411 type |= 0x02; 412 413 if (type) 414 skb_pull(skb, ETH_ALEN * 2); 415 416 type = __bnep_tx_types[type]; 417 switch (type) { 418 case BNEP_COMPRESSED_SRC_ONLY: 419 iv[il++] = (struct kvec) { eh->h_source, ETH_ALEN }; 420 len += ETH_ALEN; 421 break; 422 423 case BNEP_COMPRESSED_DST_ONLY: 424 iv[il++] = (struct kvec) { eh->h_dest, ETH_ALEN }; 425 len += ETH_ALEN; 426 break; 427 } 428 429 send: 430 iv[il++] = (struct kvec) { skb->data, skb->len }; 431 len += skb->len; 432 433 /* FIXME: linearize skb */ 434 { 435 len = kernel_sendmsg(sock, &s->msg, iv, il, len); 436 } 437 kfree_skb(skb); 438 439 if (len > 0) { 440 s->dev->stats.tx_bytes += len; 441 s->dev->stats.tx_packets++; 442 return 0; 443 } 444 445 return len; 446 } 447 448 static int bnep_session(void *arg) 449 { 450 struct bnep_session *s = arg; 451 struct net_device *dev = s->dev; 452 struct sock *sk = s->sock->sk; 453 struct sk_buff *skb; 454 wait_queue_t wait; 455 456 BT_DBG(""); 457 458 set_user_nice(current, -15); 459 460 init_waitqueue_entry(&wait, current); 461 add_wait_queue(sk_sleep(sk), &wait); 462 while (1) { 463 set_current_state(TASK_INTERRUPTIBLE); 464 465 if (atomic_read(&s->terminate)) 466 break; 467 /* RX */ 468 while ((skb = skb_dequeue(&sk->sk_receive_queue))) { 469 skb_orphan(skb); 470 if (!skb_linearize(skb)) 471 bnep_rx_frame(s, skb); 472 else 473 kfree_skb(skb); 474 } 475 476 if (sk->sk_state != BT_CONNECTED) 477 break; 478 479 /* TX */ 480 while ((skb = skb_dequeue(&sk->sk_write_queue))) 481 if (bnep_tx_frame(s, skb)) 482 break; 483 netif_wake_queue(dev); 484 485 schedule(); 486 } 487 __set_current_state(TASK_RUNNING); 488 remove_wait_queue(sk_sleep(sk), &wait); 489 490 /* Cleanup session */ 491 down_write(&bnep_session_sem); 492 493 /* Delete network device */ 494 unregister_netdev(dev); 495 496 /* Wakeup user-space polling for socket errors */ 497 s->sock->sk->sk_err = EUNATCH; 498 499 wake_up_interruptible(sk_sleep(s->sock->sk)); 500 501 /* Release the socket */ 502 fput(s->sock->file); 503 504 __bnep_unlink_session(s); 505 506 up_write(&bnep_session_sem); 507 free_netdev(dev); 508 module_put_and_exit(0); 509 return 0; 510 } 511 512 static struct device *bnep_get_device(struct bnep_session *session) 513 { 514 struct hci_conn *conn; 515 516 conn = l2cap_pi(session->sock->sk)->chan->conn->hcon; 517 if (!conn) 518 return NULL; 519 520 return &conn->dev; 521 } 522 523 static struct device_type bnep_type = { 524 .name = "bluetooth", 525 }; 526 527 int bnep_add_connection(struct bnep_connadd_req *req, struct socket *sock) 528 { 529 struct net_device *dev; 530 struct bnep_session *s, *ss; 531 u8 dst[ETH_ALEN], src[ETH_ALEN]; 532 int err; 533 534 BT_DBG(""); 535 536 if (!l2cap_is_socket(sock)) 537 return -EBADFD; 538 539 baswap((void *) dst, &l2cap_pi(sock->sk)->chan->dst); 540 baswap((void *) src, &l2cap_pi(sock->sk)->chan->src); 541 542 /* session struct allocated as private part of net_device */ 543 dev = alloc_netdev(sizeof(struct bnep_session), 544 (*req->device) ? req->device : "bnep%d", 545 NET_NAME_UNKNOWN, 546 bnep_net_setup); 547 if (!dev) 548 return -ENOMEM; 549 550 down_write(&bnep_session_sem); 551 552 ss = __bnep_get_session(dst); 553 if (ss && ss->state == BT_CONNECTED) { 554 err = -EEXIST; 555 goto failed; 556 } 557 558 s = netdev_priv(dev); 559 560 /* This is rx header therefore addresses are swapped. 561 * ie. eh.h_dest is our local address. */ 562 memcpy(s->eh.h_dest, &src, ETH_ALEN); 563 memcpy(s->eh.h_source, &dst, ETH_ALEN); 564 memcpy(dev->dev_addr, s->eh.h_dest, ETH_ALEN); 565 566 s->dev = dev; 567 s->sock = sock; 568 s->role = req->role; 569 s->state = BT_CONNECTED; 570 571 s->msg.msg_flags = MSG_NOSIGNAL; 572 573 #ifdef CONFIG_BT_BNEP_MC_FILTER 574 /* Set default mc filter */ 575 set_bit(bnep_mc_hash(dev->broadcast), (ulong *) &s->mc_filter); 576 #endif 577 578 #ifdef CONFIG_BT_BNEP_PROTO_FILTER 579 /* Set default protocol filter */ 580 bnep_set_default_proto_filter(s); 581 #endif 582 583 SET_NETDEV_DEV(dev, bnep_get_device(s)); 584 SET_NETDEV_DEVTYPE(dev, &bnep_type); 585 586 err = register_netdev(dev); 587 if (err) 588 goto failed; 589 590 __bnep_link_session(s); 591 592 __module_get(THIS_MODULE); 593 s->task = kthread_run(bnep_session, s, "kbnepd %s", dev->name); 594 if (IS_ERR(s->task)) { 595 /* Session thread start failed, gotta cleanup. */ 596 module_put(THIS_MODULE); 597 unregister_netdev(dev); 598 __bnep_unlink_session(s); 599 err = PTR_ERR(s->task); 600 goto failed; 601 } 602 603 up_write(&bnep_session_sem); 604 strcpy(req->device, dev->name); 605 return 0; 606 607 failed: 608 up_write(&bnep_session_sem); 609 free_netdev(dev); 610 return err; 611 } 612 613 int bnep_del_connection(struct bnep_conndel_req *req) 614 { 615 struct bnep_session *s; 616 int err = 0; 617 618 BT_DBG(""); 619 620 down_read(&bnep_session_sem); 621 622 s = __bnep_get_session(req->dst); 623 if (s) { 624 atomic_inc(&s->terminate); 625 wake_up_process(s->task); 626 } else 627 err = -ENOENT; 628 629 up_read(&bnep_session_sem); 630 return err; 631 } 632 633 static void __bnep_copy_ci(struct bnep_conninfo *ci, struct bnep_session *s) 634 { 635 memset(ci, 0, sizeof(*ci)); 636 memcpy(ci->dst, s->eh.h_source, ETH_ALEN); 637 strcpy(ci->device, s->dev->name); 638 ci->flags = s->flags; 639 ci->state = s->state; 640 ci->role = s->role; 641 } 642 643 int bnep_get_connlist(struct bnep_connlist_req *req) 644 { 645 struct bnep_session *s; 646 int err = 0, n = 0; 647 648 down_read(&bnep_session_sem); 649 650 list_for_each_entry(s, &bnep_session_list, list) { 651 struct bnep_conninfo ci; 652 653 __bnep_copy_ci(&ci, s); 654 655 if (copy_to_user(req->ci, &ci, sizeof(ci))) { 656 err = -EFAULT; 657 break; 658 } 659 660 if (++n >= req->cnum) 661 break; 662 663 req->ci++; 664 } 665 req->cnum = n; 666 667 up_read(&bnep_session_sem); 668 return err; 669 } 670 671 int bnep_get_conninfo(struct bnep_conninfo *ci) 672 { 673 struct bnep_session *s; 674 int err = 0; 675 676 down_read(&bnep_session_sem); 677 678 s = __bnep_get_session(ci->dst); 679 if (s) 680 __bnep_copy_ci(ci, s); 681 else 682 err = -ENOENT; 683 684 up_read(&bnep_session_sem); 685 return err; 686 } 687 688 static int __init bnep_init(void) 689 { 690 char flt[50] = ""; 691 692 #ifdef CONFIG_BT_BNEP_PROTO_FILTER 693 strcat(flt, "protocol "); 694 #endif 695 696 #ifdef CONFIG_BT_BNEP_MC_FILTER 697 strcat(flt, "multicast"); 698 #endif 699 700 BT_INFO("BNEP (Ethernet Emulation) ver %s", VERSION); 701 if (flt[0]) 702 BT_INFO("BNEP filters: %s", flt); 703 704 bnep_sock_init(); 705 return 0; 706 } 707 708 static void __exit bnep_exit(void) 709 { 710 bnep_sock_cleanup(); 711 } 712 713 module_init(bnep_init); 714 module_exit(bnep_exit); 715 716 module_param(compress_src, bool, 0644); 717 MODULE_PARM_DESC(compress_src, "Compress sources headers"); 718 719 module_param(compress_dst, bool, 0644); 720 MODULE_PARM_DESC(compress_dst, "Compress destination headers"); 721 722 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>"); 723 MODULE_DESCRIPTION("Bluetooth BNEP ver " VERSION); 724 MODULE_VERSION(VERSION); 725 MODULE_LICENSE("GPL"); 726 MODULE_ALIAS("bt-proto-4"); 727