net/bluetooth/bnep/core.c

   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         baswap((void *) dst, &l2cap_pi(sock->sk)->chan->dst);
 537         baswap((void *) src, &l2cap_pi(sock->sk)->chan->src);
 538
 539         /* session struct allocated as private part of net_device */
 540         dev = alloc_netdev(sizeof(struct bnep_session),
 541                                 (*req->device) ? req->device : "bnep%d",
 542                                 bnep_net_setup);
 543         if (!dev)
 544                 return -ENOMEM;
 545
 546         down_write(&bnep_session_sem);
 547
 548         ss = __bnep_get_session(dst);
 549         if (ss && ss->state == BT_CONNECTED) {
 550                 err = -EEXIST;
 551                 goto failed;
 552         }
 553
 554         s = netdev_priv(dev);
 555
 556         /* This is rx header therefore addresses are swapped.
 557          * ie. eh.h_dest is our local address. */
 558         memcpy(s->eh.h_dest,   &src, ETH_ALEN);
 559         memcpy(s->eh.h_source, &dst, ETH_ALEN);
 560         memcpy(dev->dev_addr, s->eh.h_dest, ETH_ALEN);
 561
 562         s->dev   = dev;
 563         s->sock  = sock;
 564         s->role  = req->role;
 565         s->state = BT_CONNECTED;
 566
 567         s->msg.msg_flags = MSG_NOSIGNAL;
 568
 569 #ifdef CONFIG_BT_BNEP_MC_FILTER
 570         /* Set default mc filter */
 571         set_bit(bnep_mc_hash(dev->broadcast), (ulong *) &s->mc_filter);
 572 #endif
 573
 574 #ifdef CONFIG_BT_BNEP_PROTO_FILTER
 575         /* Set default protocol filter */
 576         bnep_set_default_proto_filter(s);
 577 #endif
 578
 579         SET_NETDEV_DEV(dev, bnep_get_device(s));
 580         SET_NETDEV_DEVTYPE(dev, &bnep_type);
 581
 582         err = register_netdev(dev);
 583         if (err)
 584                 goto failed;
 585
 586         __bnep_link_session(s);
 587
 588         __module_get(THIS_MODULE);
 589         s->task = kthread_run(bnep_session, s, "kbnepd %s", dev->name);
 590         if (IS_ERR(s->task)) {
 591                 /* Session thread start failed, gotta cleanup. */
 592                 module_put(THIS_MODULE);
 593                 unregister_netdev(dev);
 594                 __bnep_unlink_session(s);
 595                 err = PTR_ERR(s->task);
 596                 goto failed;
 597         }
 598
 599         up_write(&bnep_session_sem);
 600         strcpy(req->device, dev->name);
 601         return 0;
 602
 603 failed:
 604         up_write(&bnep_session_sem);
 605         free_netdev(dev);
 606         return err;
 607 }
 608
 609 int bnep_del_connection(struct bnep_conndel_req *req)
 610 {
 611         struct bnep_session *s;
 612         int  err = 0;
 613
 614         BT_DBG("");
 615
 616         down_read(&bnep_session_sem);
 617
 618         s = __bnep_get_session(req->dst);
 619         if (s) {
 620                 atomic_inc(&s->terminate);
 621                 wake_up_process(s->task);
 622         } else
 623                 err = -ENOENT;
 624
 625         up_read(&bnep_session_sem);
 626         return err;
 627 }
 628
 629 static void __bnep_copy_ci(struct bnep_conninfo *ci, struct bnep_session *s)
 630 {
 631         memset(ci, 0, sizeof(*ci));
 632         memcpy(ci->dst, s->eh.h_source, ETH_ALEN);
 633         strcpy(ci->device, s->dev->name);
 634         ci->flags = s->flags;
 635         ci->state = s->state;
 636         ci->role  = s->role;
 637 }
 638
 639 int bnep_get_connlist(struct bnep_connlist_req *req)
 640 {
 641         struct bnep_session *s;
 642         int err = 0, n = 0;
 643
 644         down_read(&bnep_session_sem);
 645
 646         list_for_each_entry(s, &bnep_session_list, list) {
 647                 struct bnep_conninfo ci;
 648
 649                 __bnep_copy_ci(&ci, s);
 650
 651                 if (copy_to_user(req->ci, &ci, sizeof(ci))) {
 652                         err = -EFAULT;
 653                         break;
 654                 }
 655
 656                 if (++n >= req->cnum)
 657                         break;
 658
 659                 req->ci++;
 660         }
 661         req->cnum = n;
 662
 663         up_read(&bnep_session_sem);
 664         return err;
 665 }
 666
 667 int bnep_get_conninfo(struct bnep_conninfo *ci)
 668 {
 669         struct bnep_session *s;
 670         int err = 0;
 671
 672         down_read(&bnep_session_sem);
 673
 674         s = __bnep_get_session(ci->dst);
 675         if (s)
 676                 __bnep_copy_ci(ci, s);
 677         else
 678                 err = -ENOENT;
 679
 680         up_read(&bnep_session_sem);
 681         return err;
 682 }
 683
 684 static int __init bnep_init(void)
 685 {
 686         char flt[50] = "";
 687
 688 #ifdef CONFIG_BT_BNEP_PROTO_FILTER
 689         strcat(flt, "protocol ");
 690 #endif
 691
 692 #ifdef CONFIG_BT_BNEP_MC_FILTER
 693         strcat(flt, "multicast");
 694 #endif
 695
 696         BT_INFO("BNEP (Ethernet Emulation) ver %s", VERSION);
 697         if (flt[0])
 698                 BT_INFO("BNEP filters: %s", flt);
 699
 700         bnep_sock_init();
 701         return 0;
 702 }
 703
 704 static void __exit bnep_exit(void)
 705 {
 706         bnep_sock_cleanup();
 707 }
 708
 709 module_init(bnep_init);
 710 module_exit(bnep_exit);
 711
 712 module_param(compress_src, bool, 0644);
 713 MODULE_PARM_DESC(compress_src, "Compress sources headers");
 714
 715 module_param(compress_dst, bool, 0644);
 716 MODULE_PARM_DESC(compress_dst, "Compress destination headers");
 717
 718 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
 719 MODULE_DESCRIPTION("Bluetooth BNEP ver " VERSION);
 720 MODULE_VERSION(VERSION);
 721 MODULE_LICENSE("GPL");
 722 MODULE_ALIAS("bt-proto-4");