contrib/libpcap/pcap-bt-linux.c

   1 /*
   2  * Copyright (c) 2006 Paolo Abeni (Italy)
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  * 1. Redistributions of source code must retain the above copyright
  10  * notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  * notice, this list of conditions and the following disclaimer in the
  13  * documentation and/or other materials provided with the distribution.
  14  * 3. The name of the author may not be used to endorse or promote
  15  * products derived from this software without specific prior written
  16  * permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  19  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  20  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  21  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  22  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  23  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  24  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  28  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  29  *
  30  * Bluetooth sniffing API implementation for Linux platform
  31  * By Paolo Abeni <paolo.abeni@email.it>
  32  *
  33  */
  34 #ifndef lint
  35 static const char rcsid[] _U_ =
  36     "@(#) $Header: /tcpdump/master/libpcap/pcap-bt-linux.c,v 1.9.2.6 2008-07-01 07:06:37 guy Exp $ (LBL)";
  37 #endif
  38
  39 #ifdef HAVE_CONFIG_H
  40 #include "config.h"
  41 #endif
  42
  43 #include "pcap-int.h"
  44 #include "pcap-bt-linux.h"
  45 #include "pcap/bluetooth.h"
  46
  47 #ifdef NEED_STRERROR_H
  48 #include "strerror.h"
  49 #endif
  50
  51 #include <errno.h>
  52 #include <stdlib.h>
  53 #include <unistd.h>
  54 #include <fcntl.h>
  55 #include <string.h>
  56 #include <sys/ioctl.h>
  57 #include <sys/socket.h>
  58 #include <arpa/inet.h>
  59
  60 #include <bluetooth/bluetooth.h>
  61 #include <bluetooth/hci.h>
  62
  63 #define BT_IFACE "bluetooth"
  64 #define BT_CTRL_SIZE 128
  65
  66 /* forward declaration */
  67 static int bt_activate(pcap_t *);
  68 static int bt_read_linux(pcap_t *, int , pcap_handler , u_char *);
  69 static int bt_inject_linux(pcap_t *, const void *, size_t);
  70 static int bt_setfilter_linux(pcap_t *, struct bpf_program *);
  71 static int bt_setdirection_linux(pcap_t *, pcap_direction_t);
  72 static int bt_stats_linux(pcap_t *, struct pcap_stat *);
  73
  74 int
  75 bt_platform_finddevs(pcap_if_t **alldevsp, char *err_str)
  76 {
  77         pcap_if_t *found_dev = *alldevsp;
  78         struct hci_dev_list_req *dev_list;
  79         struct hci_dev_req *dev_req;
  80         int i, sock;
  81         int ret = 0;
  82
  83         sock  = socket(AF_BLUETOOTH, SOCK_RAW, BTPROTO_HCI);
  84         if (sock < 0)
  85         {
  86                 /* if bluetooth is not supported this this is not fatal*/
  87                 if (errno == EAFNOSUPPORT)
  88                         return 0;
  89                 snprintf(err_str, PCAP_ERRBUF_SIZE, "Can't open raw Bluetooth socket %d:%s",
  90                         errno, strerror(errno));
  91                 return -1;
  92         }
  93
  94         dev_list = malloc(HCI_MAX_DEV * sizeof(*dev_req) + sizeof(*dev_list));
  95         if (!dev_list)
  96         {
  97                 snprintf(err_str, PCAP_ERRBUF_SIZE, "Can't allocate %zu bytes for Bluetooth device list",
  98                         HCI_MAX_DEV * sizeof(*dev_req) + sizeof(*dev_list));
  99                 ret = -1;
 100                 goto done;
 101         }
 102
 103         dev_list->dev_num = HCI_MAX_DEV;
 104
 105         if (ioctl(sock, HCIGETDEVLIST, (void *) dev_list) < 0)
 106         {
 107                 snprintf(err_str, PCAP_ERRBUF_SIZE, "Can't get Bluetooth device list via ioctl %d:%s",
 108                         errno, strerror(errno));
 109                 ret = -1;
 110                 goto free;
 111         }
 112
 113         dev_req = dev_list->dev_req;
 114         for (i = 0; i < dev_list->dev_num; i++, dev_req++) {
 115                 char dev_name[20], dev_descr[30];
 116
 117                 snprintf(dev_name, 20, BT_IFACE"%d", dev_req->dev_id);
 118                 snprintf(dev_descr, 30, "Bluetooth adapter number %d", i);
 119
 120                 if (pcap_add_if(&found_dev, dev_name, 0,
 121                        dev_descr, err_str) < 0)
 122                 {
 123                         ret = -1;
 124                         break;
 125                 }
 126
 127         }
 128
 129 free:
 130         free(dev_list);
 131
 132 done:
 133         close(sock);
 134         return ret;
 135 }
 136
 137 pcap_t *
 138 bt_create(const char *device, char *ebuf)
 139 {
 140         pcap_t *p;
 141
 142         p = pcap_create_common(device, ebuf);
 143         if (p == NULL)
 144                 return (NULL);
 145
 146         p->activate_op = bt_activate;
 147         return (p);
 148 }
 149
 150 static int
 151 bt_activate(pcap_t* handle)
 152 {
 153         struct sockaddr_hci addr;
 154         int opt;
 155         int             dev_id;
 156         struct hci_filter       flt;
 157         int err = PCAP_ERROR;
 158
 159         /* get bt interface id */
 160         if (sscanf(handle->opt.source, BT_IFACE"%d", &dev_id) != 1)
 161         {
 162                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
 163                         "Can't get Bluetooth device index from %s",
 164                          handle->opt.source);
 165                 return PCAP_ERROR;
 166         }
 167
 168         /* Initialize some components of the pcap structure. */
 169         handle->bufsize = handle->snapshot+BT_CTRL_SIZE+sizeof(pcap_bluetooth_h4_header);
 170         handle->offset = BT_CTRL_SIZE;
 171         handle->linktype = DLT_BLUETOOTH_HCI_H4_WITH_PHDR;
 172
 173         handle->read_op = bt_read_linux;
 174         handle->inject_op = bt_inject_linux;
 175         handle->setfilter_op = bt_setfilter_linux;
 176         handle->setdirection_op = bt_setdirection_linux;
 177         handle->set_datalink_op = NULL; /* can't change data link type */
 178         handle->getnonblock_op = pcap_getnonblock_fd;
 179         handle->setnonblock_op = pcap_setnonblock_fd;
 180         handle->stats_op = bt_stats_linux;
 181         handle->md.ifindex = dev_id;
 182
 183         /* Create HCI socket */
 184         handle->fd = socket(AF_BLUETOOTH, SOCK_RAW, BTPROTO_HCI);
 185         if (handle->fd < 0) {
 186                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Can't create raw socket %d:%s",
 187                         errno, strerror(errno));
 188                 return PCAP_ERROR;
 189         }
 190
 191         handle->buffer = malloc(handle->bufsize);
 192         if (!handle->buffer) {
 193                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Can't allocate dump buffer: %s",
 194                         pcap_strerror(errno));
 195                 goto close_fail;
 196         }
 197
 198         opt = 1;
 199         if (setsockopt(handle->fd, SOL_HCI, HCI_DATA_DIR, &opt, sizeof(opt)) < 0) {
 200                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Can't enable data direction info %d:%s",
 201                         errno, strerror(errno));
 202                 goto close_fail;
 203         }
 204
 205         opt = 1;
 206         if (setsockopt(handle->fd, SOL_HCI, HCI_TIME_STAMP, &opt, sizeof(opt)) < 0) {
 207                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Can't enable time stamp %d:%s",
 208                         errno, strerror(errno));
 209                 goto close_fail;
 210         }
 211
 212         /* Setup filter, do not call hci function to avoid dependence on
 213          * external libs        */
 214         memset(&flt, 0, sizeof(flt));
 215         memset((void *) &flt.type_mask, 0xff, sizeof(flt.type_mask));
 216         memset((void *) &flt.event_mask, 0xff, sizeof(flt.event_mask));
 217         if (setsockopt(handle->fd, SOL_HCI, HCI_FILTER, &flt, sizeof(flt)) < 0) {
 218                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Can't set filter %d:%s",
 219                         errno, strerror(errno));
 220                 goto close_fail;
 221         }
 222
 223
 224         /* Bind socket to the HCI device */
 225         addr.hci_family = AF_BLUETOOTH;
 226         addr.hci_dev = handle->md.ifindex;
 227         if (bind(handle->fd, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
 228                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Can't attach to device %d %d:%s",
 229                         handle->md.ifindex, errno, strerror(errno));
 230                 goto close_fail;
 231         }
 232
 233         if (handle->opt.rfmon) {
 234                 /*
 235                  * Monitor mode doesn't apply to Bluetooth devices.
 236                  */
 237                 err = PCAP_ERROR_RFMON_NOTSUP;
 238                 goto close_fail;
 239         }
 240
 241         if (handle->opt.buffer_size == 0) {
 242                 /*
 243                  * Set the socket buffer size to the specified value.
 244                  */
 245                 if (setsockopt(handle->fd, SOL_SOCKET, SO_RCVBUF,
 246                     &handle->opt.buffer_size,
 247                     sizeof(handle->opt.buffer_size)) == -1) {
 248                         snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
 249                                  "SO_RCVBUF: %s", pcap_strerror(errno));
 250                         goto close_fail;
 251                 }
 252         }
 253
 254         handle->selectable_fd = handle->fd;
 255         return 0;
 256
 257 close_fail:
 258         pcap_cleanup_live_common(handle);
 259         return err;
 260 }
 261
 262 static int
 263 bt_read_linux(pcap_t *handle, int max_packets, pcap_handler callback, u_char *user)
 264 {
 265         struct cmsghdr *cmsg;
 266         struct msghdr msg;
 267         struct iovec  iv;
 268         struct pcap_pkthdr pkth;
 269         pcap_bluetooth_h4_header* bthdr;
 270
 271         bthdr = (pcap_bluetooth_h4_header*) &handle->buffer[handle->offset];
 272         iv.iov_base = &handle->buffer[handle->offset+sizeof(pcap_bluetooth_h4_header)];
 273         iv.iov_len  = handle->snapshot;
 274
 275         memset(&msg, 0, sizeof(msg));
 276         msg.msg_iov = &iv;
 277         msg.msg_iovlen = 1;
 278         msg.msg_control = handle->buffer;
 279         msg.msg_controllen = handle->offset;
 280
 281         /* ignore interrupt system call error */
 282         do {
 283                 pkth.caplen = recvmsg(handle->fd, &msg, 0);
 284                 if (handle->break_loop)
 285                 {
 286                         handle->break_loop = 0;
 287                         return -2;
 288                 }
 289         } while ((pkth.caplen == -1) && (errno == EINTR));
 290
 291
 292         if (pkth.caplen < 0) {
 293                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Can't receive packet %d:%s",
 294                         errno, strerror(errno));
 295                 return -1;
 296         }
 297
 298         /* get direction and timestamp*/
 299         cmsg = CMSG_FIRSTHDR(&msg);
 300         int in=0;
 301         while (cmsg) {
 302                 switch (cmsg->cmsg_type) {
 303                         case HCI_CMSG_DIR:
 304                                 in = *((int *) CMSG_DATA(cmsg));
 305                                 break;
 306                         case HCI_CMSG_TSTAMP:
 307                                 pkth.ts = *((struct timeval *) CMSG_DATA(cmsg));
 308                                 break;
 309                 }
 310                 cmsg = CMSG_NXTHDR(&msg, cmsg);
 311         }
 312         if ((in && (handle->direction == PCAP_D_OUT)) ||
 313                                 ((!in) && (handle->direction == PCAP_D_IN)))
 314                 return 0;
 315
 316         bthdr->direction = htonl(in != 0);
 317         pkth.caplen+=sizeof(pcap_bluetooth_h4_header);
 318         pkth.len = pkth.caplen;
 319         callback(user, &pkth, &handle->buffer[handle->offset]);
 320         return 1;
 321 }
 322
 323 static int
 324 bt_inject_linux(pcap_t *handle, const void *buf, size_t size)
 325 {
 326         snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "inject not supported on "
 327                 "bluetooth devices");
 328         return (-1);
 329 }
 330
 331
 332 static int
 333 bt_stats_linux(pcap_t *handle, struct pcap_stat *stats)
 334 {
 335         int ret;
 336         struct hci_dev_info dev_info;
 337         struct hci_dev_stats * s = &dev_info.stat;
 338         dev_info.dev_id = handle->md.ifindex;
 339
 340         /* ingnore eintr */
 341         do {
 342                 ret = ioctl(handle->fd, HCIGETDEVINFO, (void *)&dev_info);
 343         } while ((ret == -1) && (errno == EINTR));
 344
 345         if (ret < 0) {
 346                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "can get stats"
 347                         " via ioctl %d:%s", errno, strerror(errno));
 348                 return (-1);
 349
 350         }
 351
 352         /* we receive both rx and tx frames, so comulate all stats */
 353         stats->ps_recv = s->evt_rx + s->acl_rx + s->sco_rx + s->cmd_tx +
 354                 s->acl_tx +s->sco_tx;
 355         stats->ps_drop = s->err_rx + s->err_tx;
 356         stats->ps_ifdrop = 0;
 357         return 0;
 358 }
 359
 360 static int
 361 bt_setfilter_linux(pcap_t *p, struct bpf_program *fp)
 362 {
 363         return 0;
 364 }
 365
 366
 367 static int
 368 bt_setdirection_linux(pcap_t *p, pcap_direction_t d)
 369 {
 370         p->direction = d;
 371         return 0;
 372 }