The Tcpdump Group git mirrors - libpcap/blob - 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 1.15 2008-07-01 07:05:54 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_setdirection_linux(pcap_t *, pcap_direction_t);
  71 static int bt_stats_linux(pcap_t *, struct pcap_stat *);
  72
  73 int
  74 bt_platform_finddevs(pcap_if_t **alldevsp, char *err_str)
  75 {
  76         pcap_if_t *found_dev = *alldevsp;
  77         struct hci_dev_list_req *dev_list;
  78         struct hci_dev_req *dev_req;
  79         int i, sock;
  80         int ret = 0;
  81
  82         sock  = socket(AF_BLUETOOTH, SOCK_RAW, BTPROTO_HCI);
  83         if (sock < 0)
  84         {
  85                 /* if bluetooth is not supported this this is not fatal*/
  86                 if (errno == EAFNOSUPPORT)
  87                         return 0;
  88                 snprintf(err_str, PCAP_ERRBUF_SIZE, "Can't open raw Bluetooth socket %d:%s",
  89                         errno, strerror(errno));
  90                 return -1;
  91         }
  92
  93         dev_list = malloc(HCI_MAX_DEV * sizeof(*dev_req) + sizeof(*dev_list));
  94         if (!dev_list)
  95         {
  96                 snprintf(err_str, PCAP_ERRBUF_SIZE, "Can't allocate %zu bytes for Bluetooth device list",
  97                         HCI_MAX_DEV * sizeof(*dev_req) + sizeof(*dev_list));
  98                 ret = -1;
  99                 goto done;
 100         }
 101
 102         dev_list->dev_num = HCI_MAX_DEV;
 103
 104         if (ioctl(sock, HCIGETDEVLIST, (void *) dev_list) < 0)
 105         {
 106                 snprintf(err_str, PCAP_ERRBUF_SIZE, "Can't get Bluetooth device list via ioctl %d:%s",
 107                         errno, strerror(errno));
 108                 ret = -1;
 109                 goto free;
 110         }
 111
 112         dev_req = dev_list->dev_req;
 113         for (i = 0; i < dev_list->dev_num; i++, dev_req++) {
 114                 char dev_name[20], dev_descr[30];
 115
 116                 snprintf(dev_name, 20, BT_IFACE"%d", dev_req->dev_id);
 117                 snprintf(dev_descr, 30, "Bluetooth adapter number %d", i);
 118
 119                 if (pcap_add_if(&found_dev, dev_name, 0,
 120                        dev_descr, err_str) < 0)
 121                 {
 122                         ret = -1;
 123                         break;
 124                 }
 125
 126         }
 127
 128 free:
 129         free(dev_list);
 130
 131 done:
 132         close(sock);
 133         return ret;
 134 }
 135
 136 pcap_t *
 137 bt_create(const char *device, char *ebuf)
 138 {
 139         pcap_t *p;
 140
 141         p = pcap_create_common(device, ebuf);
 142         if (p == NULL)
 143                 return (NULL);
 144
 145         p->activate_op = bt_activate;
 146         return (p);
 147 }
 148
 149 static int
 150 bt_activate(pcap_t* handle)
 151 {
 152         struct sockaddr_hci addr;
 153         int opt;
 154         int             dev_id;
 155         struct hci_filter       flt;
 156         int err = PCAP_ERROR;
 157
 158         /* get bt interface id */
 159         if (sscanf(handle->opt.source, BT_IFACE"%d", &dev_id) != 1)
 160         {
 161                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
 162                         "Can't get Bluetooth device index from %s",
 163                          handle->opt.source);
 164                 return PCAP_ERROR;
 165         }
 166
 167         /* Initialize some components of the pcap structure. */
 168         handle->bufsize = handle->snapshot+BT_CTRL_SIZE+sizeof(pcap_bluetooth_h4_header);
 169         handle->offset = BT_CTRL_SIZE;
 170         handle->linktype = DLT_BLUETOOTH_HCI_H4_WITH_PHDR;
 171
 172         handle->read_op = bt_read_linux;
 173         handle->inject_op = bt_inject_linux;
 174         handle->setfilter_op = install_bpf_program; /* no kernel filtering */
 175         handle->setdirection_op = bt_setdirection_linux;
 176         handle->set_datalink_op = NULL; /* can't change data link type */
 177         handle->getnonblock_op = pcap_getnonblock_fd;
 178         handle->setnonblock_op = pcap_setnonblock_fd;
 179         handle->stats_op = bt_stats_linux;
 180         handle->md.ifindex = dev_id;
 181
 182         /* Create HCI socket */
 183         handle->fd = socket(AF_BLUETOOTH, SOCK_RAW, BTPROTO_HCI);
 184         if (handle->fd < 0) {
 185                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Can't create raw socket %d:%s",
 186                         errno, strerror(errno));
 187                 return PCAP_ERROR;
 188         }
 189
 190         handle->buffer = malloc(handle->bufsize);
 191         if (!handle->buffer) {
 192                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Can't allocate dump buffer: %s",
 193                         pcap_strerror(errno));
 194                 goto close_fail;
 195         }
 196
 197         opt = 1;
 198         if (setsockopt(handle->fd, SOL_HCI, HCI_DATA_DIR, &opt, sizeof(opt)) < 0) {
 199                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Can't enable data direction info %d:%s",
 200                         errno, strerror(errno));
 201                 goto close_fail;
 202         }
 203
 204         opt = 1;
 205         if (setsockopt(handle->fd, SOL_HCI, HCI_TIME_STAMP, &opt, sizeof(opt)) < 0) {
 206                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Can't enable time stamp %d:%s",
 207                         errno, strerror(errno));
 208                 goto close_fail;
 209         }
 210
 211         /* Setup filter, do not call hci function to avoid dependence on
 212          * external libs        */
 213         memset(&flt, 0, sizeof(flt));
 214         memset((void *) &flt.type_mask, 0xff, sizeof(flt.type_mask));
 215         memset((void *) &flt.event_mask, 0xff, sizeof(flt.event_mask));
 216         if (setsockopt(handle->fd, SOL_HCI, HCI_FILTER, &flt, sizeof(flt)) < 0) {
 217                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Can't set filter %d:%s",
 218                         errno, strerror(errno));
 219                 goto close_fail;
 220         }
 221
 222
 223         /* Bind socket to the HCI device */
 224         addr.hci_family = AF_BLUETOOTH;
 225         addr.hci_dev = handle->md.ifindex;
 226         if (bind(handle->fd, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
 227                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Can't attach to device %d %d:%s",
 228                         handle->md.ifindex, errno, strerror(errno));
 229                 goto close_fail;
 230         }
 231
 232         if (handle->opt.rfmon) {
 233                 /*
 234                  * Monitor mode doesn't apply to Bluetooth devices.
 235                  */
 236                 err = PCAP_ERROR_RFMON_NOTSUP;
 237                 goto close_fail;
 238         }
 239
 240         if (handle->opt.buffer_size == 0) {
 241                 /*
 242                  * Set the socket buffer size to the specified value.
 243                  */
 244                 if (setsockopt(handle->fd, SOL_SOCKET, SO_RCVBUF,
 245                     &handle->opt.buffer_size,
 246                     sizeof(handle->opt.buffer_size)) == -1) {
 247                         snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
 248                                  "SO_RCVBUF: %s", pcap_strerror(errno));
 249                         goto close_fail;
 250                 }
 251         }
 252
 253         handle->selectable_fd = handle->fd;
 254         return 0;
 255
 256 close_fail:
 257         pcap_cleanup_live_common(handle);
 258         return err;
 259 }
 260
 261 static int
 262 bt_read_linux(pcap_t *handle, int max_packets, pcap_handler callback, u_char *user)
 263 {
 264         struct cmsghdr *cmsg;
 265         struct msghdr msg;
 266         struct iovec  iv;
 267         struct pcap_pkthdr pkth;
 268         pcap_bluetooth_h4_header* bthdr;
 269
 270         bthdr = (pcap_bluetooth_h4_header*) &handle->buffer[handle->offset];
 271         iv.iov_base = &handle->buffer[handle->offset+sizeof(pcap_bluetooth_h4_header)];
 272         iv.iov_len  = handle->snapshot;
 273
 274         memset(&msg, 0, sizeof(msg));
 275         msg.msg_iov = &iv;
 276         msg.msg_iovlen = 1;
 277         msg.msg_control = handle->buffer;
 278         msg.msg_controllen = handle->offset;
 279
 280         /* ignore interrupt system call error */
 281         do {
 282                 pkth.caplen = recvmsg(handle->fd, &msg, 0);
 283                 if (handle->break_loop)
 284                 {
 285                         handle->break_loop = 0;
 286                         return -2;
 287                 }
 288         } while ((pkth.caplen == -1) && (errno == EINTR));
 289
 290
 291         if (pkth.caplen < 0) {
 292                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Can't receive packet %d:%s",
 293                         errno, strerror(errno));
 294                 return -1;
 295         }
 296
 297         /* get direction and timestamp*/
 298         cmsg = CMSG_FIRSTHDR(&msg);
 299         int in=0;
 300         while (cmsg) {
 301                 switch (cmsg->cmsg_type) {
 302                         case HCI_CMSG_DIR:
 303                                 memcpy(&in, CMSG_DATA(cmsg), sizeof in);
 304                                 break;
 305                         case HCI_CMSG_TSTAMP:
 306                                 memcpy(&pkth.ts, CMSG_DATA(cmsg),
 307                                     sizeof pkth.ts);
 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         if (handle->fcode.bf_insns == NULL ||
 320             bpf_filter(handle->fcode.bf_insns, &handle->buffer[handle->offset],
 321               pkth.len, pkth.caplen)) {
 322                 callback(user, &pkth, &handle->buffer[handle->offset]);
 323                 return 1;
 324         }
 325         return 0;       /* didn't pass filter */
 326 }
 327
 328 static int
 329 bt_inject_linux(pcap_t *handle, const void *buf, size_t size)
 330 {
 331         snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "inject not supported on "
 332                 "bluetooth devices");
 333         return (-1);
 334 }
 335
 336
 337 static int
 338 bt_stats_linux(pcap_t *handle, struct pcap_stat *stats)
 339 {
 340         int ret;
 341         struct hci_dev_info dev_info;
 342         struct hci_dev_stats * s = &dev_info.stat;
 343         dev_info.dev_id = handle->md.ifindex;
 344
 345         /* ingnore eintr */
 346         do {
 347                 ret = ioctl(handle->fd, HCIGETDEVINFO, (void *)&dev_info);
 348         } while ((ret == -1) && (errno == EINTR));
 349
 350         if (ret < 0) {
 351                 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "can get stats"
 352                         " via ioctl %d:%s", errno, strerror(errno));
 353                 return (-1);
 354
 355         }
 356
 357         /* we receive both rx and tx frames, so comulate all stats */
 358         stats->ps_recv = s->evt_rx + s->acl_rx + s->sco_rx + s->cmd_tx +
 359                 s->acl_tx +s->sco_tx;
 360         stats->ps_drop = s->err_rx + s->err_tx;
 361         stats->ps_ifdrop = 0;
 362         return 0;
 363 }
 364
 365 static int
 366 bt_setdirection_linux(pcap_t *p, pcap_direction_t d)
 367 {
 368         p->direction = d;
 369         return 0;
 370 }