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, 89 "Can't open raw Bluetooth socket: %s", 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, 107 "Can't get Bluetooth device list via ioctl: %s", 108 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 = install_bpf_program; /* no kernel filtering */ 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, 187 "Can't create raw socket: %s", 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, 201 "Can't enable data direction info: %s", 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, 208 "Can't enable time stamp: %s", 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, 219 "Can't set filter: %s", 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, 229 "Can't attach to device %d: %s", handle->md.ifindex, 230 strerror(errno)); 231 goto close_fail; 232 } 233 234 if (handle->opt.rfmon) { 235 /* 236 * Monitor mode doesn't apply to Bluetooth devices. 237 */ 238 err = PCAP_ERROR_RFMON_NOTSUP; 239 goto close_fail; 240 } 241 242 if (handle->opt.buffer_size != 0) { 243 /* 244 * Set the socket buffer size to the specified value. 245 */ 246 if (setsockopt(handle->fd, SOL_SOCKET, SO_RCVBUF, 247 &handle->opt.buffer_size, 248 sizeof(handle->opt.buffer_size)) == -1) { 249 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, 250 "SO_RCVBUF: %s", pcap_strerror(errno)); 251 goto close_fail; 252 } 253 } 254 255 handle->selectable_fd = handle->fd; 256 return 0; 257 258 close_fail: 259 pcap_cleanup_live_common(handle); 260 return err; 261 } 262 263 static int 264 bt_read_linux(pcap_t *handle, int max_packets, pcap_handler callback, u_char *user) 265 { 266 struct cmsghdr *cmsg; 267 struct msghdr msg; 268 struct iovec iv; 269 ssize_t ret; 270 struct pcap_pkthdr pkth; 271 pcap_bluetooth_h4_header* bthdr; 272 273 bthdr = (pcap_bluetooth_h4_header*) &handle->buffer[handle->offset]; 274 iv.iov_base = &handle->buffer[handle->offset+sizeof(pcap_bluetooth_h4_header)]; 275 iv.iov_len = handle->snapshot; 276 277 memset(&msg, 0, sizeof(msg)); 278 msg.msg_iov = &iv; 279 msg.msg_iovlen = 1; 280 msg.msg_control = handle->buffer; 281 msg.msg_controllen = handle->offset; 282 283 /* ignore interrupt system call error */ 284 do { 285 ret = recvmsg(handle->fd, &msg, 0); 286 if (handle->break_loop) 287 { 288 handle->break_loop = 0; 289 return -2; 290 } 291 } while ((ret == -1) && (errno == EINTR)); 292 293 if (ret < 0) { 294 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, 295 "Can't receive packet: %s", strerror(errno)); 296 return -1; 297 } 298 299 pkth.caplen = ret; 300 301 /* get direction and timestamp*/ 302 cmsg = CMSG_FIRSTHDR(&msg); 303 int in=0; 304 while (cmsg) { 305 switch (cmsg->cmsg_type) { 306 case HCI_CMSG_DIR: 307 memcpy(&in, CMSG_DATA(cmsg), sizeof in); 308 break; 309 case HCI_CMSG_TSTAMP: 310 memcpy(&pkth.ts, CMSG_DATA(cmsg), 311 sizeof pkth.ts); 312 break; 313 } 314 cmsg = CMSG_NXTHDR(&msg, cmsg); 315 } 316 if ((in && (handle->direction == PCAP_D_OUT)) || 317 ((!in) && (handle->direction == PCAP_D_IN))) 318 return 0; 319 320 bthdr->direction = htonl(in != 0); 321 pkth.caplen+=sizeof(pcap_bluetooth_h4_header); 322 pkth.len = pkth.caplen; 323 if (handle->fcode.bf_insns == NULL || 324 bpf_filter(handle->fcode.bf_insns, &handle->buffer[handle->offset], 325 pkth.len, pkth.caplen)) { 326 callback(user, &pkth, &handle->buffer[handle->offset]); 327 return 1; 328 } 329 return 0; /* didn't pass filter */ 330 } 331 332 static int 333 bt_inject_linux(pcap_t *handle, const void *buf, size_t size) 334 { 335 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "inject not supported on " 336 "bluetooth devices"); 337 return (-1); 338 } 339 340 341 static int 342 bt_stats_linux(pcap_t *handle, struct pcap_stat *stats) 343 { 344 int ret; 345 struct hci_dev_info dev_info; 346 struct hci_dev_stats * s = &dev_info.stat; 347 dev_info.dev_id = handle->md.ifindex; 348 349 /* ignore eintr */ 350 do { 351 ret = ioctl(handle->fd, HCIGETDEVINFO, (void *)&dev_info); 352 } while ((ret == -1) && (errno == EINTR)); 353 354 if (ret < 0) { 355 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, 356 "Can't get stats via ioctl: %s", strerror(errno)); 357 return (-1); 358 359 } 360 361 /* we receive both rx and tx frames, so comulate all stats */ 362 stats->ps_recv = s->evt_rx + s->acl_rx + s->sco_rx + s->cmd_tx + 363 s->acl_tx +s->sco_tx; 364 stats->ps_drop = s->err_rx + s->err_tx; 365 stats->ps_ifdrop = 0; 366 return 0; 367 } 368 369 static int 370 bt_setdirection_linux(pcap_t *p, pcap_direction_t d) 371 { 372 p->direction = d; 373 return 0; 374 } 375