pcap-bt-linux.c
11.4 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
/*
* Copyright (c) 2006 Paolo Abeni (Italy)
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* Bluetooth sniffing API implementation for Linux platform
* By Paolo Abeni <paolo.abeni@email.it>
*
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include "pcap-int.h"
#include "pcap-bt-linux.h"
#include "pcap/bluetooth.h"
#include <errno.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <bluetooth/bluetooth.h>
#include <bluetooth/hci.h>
#define BT_IFACE "bluetooth"
#define BT_CTRL_SIZE 128
/* forward declaration */
static int bt_activate(pcap_t *);
static int bt_read_linux(pcap_t *, int , pcap_handler , u_char *);
static int bt_inject_linux(pcap_t *, const void *, size_t);
static int bt_setdirection_linux(pcap_t *, pcap_direction_t);
static int bt_stats_linux(pcap_t *, struct pcap_stat *);
/*
* Private data for capturing on Linux Bluetooth devices.
*/
struct pcap_bt {
int dev_id; /* device ID of device we're bound to */
};
int
bt_findalldevs(pcap_if_list_t *devlistp, char *err_str)
{
struct hci_dev_list_req *dev_list;
struct hci_dev_req *dev_req;
int i, sock;
int ret = 0;
sock = socket(AF_BLUETOOTH, SOCK_RAW, BTPROTO_HCI);
if (sock < 0)
{
/* if bluetooth is not supported this this is not fatal*/
if (errno == EAFNOSUPPORT)
return 0;
pcap_fmt_errmsg_for_errno(err_str, PCAP_ERRBUF_SIZE,
errno, "Can't open raw Bluetooth socket");
return -1;
}
dev_list = malloc(HCI_MAX_DEV * sizeof(*dev_req) + sizeof(*dev_list));
if (!dev_list)
{
pcap_snprintf(err_str, PCAP_ERRBUF_SIZE, "Can't allocate %zu bytes for Bluetooth device list",
HCI_MAX_DEV * sizeof(*dev_req) + sizeof(*dev_list));
ret = -1;
goto done;
}
dev_list->dev_num = HCI_MAX_DEV;
if (ioctl(sock, HCIGETDEVLIST, (void *) dev_list) < 0)
{
pcap_fmt_errmsg_for_errno(err_str, PCAP_ERRBUF_SIZE,
errno, "Can't get Bluetooth device list via ioctl");
ret = -1;
goto free;
}
dev_req = dev_list->dev_req;
for (i = 0; i < dev_list->dev_num; i++, dev_req++) {
char dev_name[20], dev_descr[30];
pcap_snprintf(dev_name, 20, BT_IFACE"%d", dev_req->dev_id);
pcap_snprintf(dev_descr, 30, "Bluetooth adapter number %d", i);
/*
* Bluetooth is a wireless technology.
* XXX - if there's the notion of associating with a
* network, and we can determine whether the interface
* is associated with a network, check that and set
* the status to PCAP_IF_CONNECTION_STATUS_CONNECTED
* or PCAP_IF_CONNECTION_STATUS_DISCONNECTED.
*/
if (add_dev(devlistp, dev_name, PCAP_IF_WIRELESS, dev_descr, err_str) == NULL)
{
ret = -1;
break;
}
}
free:
free(dev_list);
done:
close(sock);
return ret;
}
pcap_t *
bt_create(const char *device, char *ebuf, int *is_ours)
{
const char *cp;
char *cpend;
long devnum;
pcap_t *p;
/* Does this look like a Bluetooth device? */
cp = strrchr(device, '/');
if (cp == NULL)
cp = device;
/* Does it begin with BT_IFACE? */
if (strncmp(cp, BT_IFACE, sizeof BT_IFACE - 1) != 0) {
/* Nope, doesn't begin with BT_IFACE */
*is_ours = 0;
return NULL;
}
/* Yes - is BT_IFACE followed by a number? */
cp += sizeof BT_IFACE - 1;
devnum = strtol(cp, &cpend, 10);
if (cpend == cp || *cpend != '\0') {
/* Not followed by a number. */
*is_ours = 0;
return NULL;
}
if (devnum < 0) {
/* Followed by a non-valid number. */
*is_ours = 0;
return NULL;
}
/* OK, it's probably ours. */
*is_ours = 1;
p = pcap_create_common(ebuf, sizeof (struct pcap_bt));
if (p == NULL)
return (NULL);
p->activate_op = bt_activate;
return (p);
}
static int
bt_activate(pcap_t* handle)
{
struct pcap_bt *handlep = handle->priv;
struct sockaddr_hci addr;
int opt;
int dev_id;
struct hci_filter flt;
int err = PCAP_ERROR;
/* get bt interface id */
if (sscanf(handle->opt.device, BT_IFACE"%d", &dev_id) != 1)
{
pcap_snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
"Can't get Bluetooth device index from %s",
handle->opt.device);
return PCAP_ERROR;
}
/*
* Turn a negative snapshot value (invalid), a snapshot value of
* 0 (unspecified), or a value bigger than the normal maximum
* value, into the maximum allowed value.
*
* If some application really *needs* a bigger snapshot
* length, we should just increase MAXIMUM_SNAPLEN.
*/
if (handle->snapshot <= 0 || handle->snapshot > MAXIMUM_SNAPLEN)
handle->snapshot = MAXIMUM_SNAPLEN;
/* Initialize some components of the pcap structure. */
handle->bufsize = BT_CTRL_SIZE+sizeof(pcap_bluetooth_h4_header)+handle->snapshot;
handle->linktype = DLT_BLUETOOTH_HCI_H4_WITH_PHDR;
handle->read_op = bt_read_linux;
handle->inject_op = bt_inject_linux;
handle->setfilter_op = install_bpf_program; /* no kernel filtering */
handle->setdirection_op = bt_setdirection_linux;
handle->set_datalink_op = NULL; /* can't change data link type */
handle->getnonblock_op = pcap_getnonblock_fd;
handle->setnonblock_op = pcap_setnonblock_fd;
handle->stats_op = bt_stats_linux;
handlep->dev_id = dev_id;
/* Create HCI socket */
handle->fd = socket(AF_BLUETOOTH, SOCK_RAW, BTPROTO_HCI);
if (handle->fd < 0) {
pcap_fmt_errmsg_for_errno(handle->errbuf, PCAP_ERRBUF_SIZE,
errno, "Can't create raw socket");
return PCAP_ERROR;
}
handle->buffer = malloc(handle->bufsize);
if (!handle->buffer) {
pcap_fmt_errmsg_for_errno(handle->errbuf, PCAP_ERRBUF_SIZE,
errno, "Can't allocate dump buffer");
goto close_fail;
}
opt = 1;
if (setsockopt(handle->fd, SOL_HCI, HCI_DATA_DIR, &opt, sizeof(opt)) < 0) {
pcap_fmt_errmsg_for_errno(handle->errbuf, PCAP_ERRBUF_SIZE,
errno, "Can't enable data direction info");
goto close_fail;
}
opt = 1;
if (setsockopt(handle->fd, SOL_HCI, HCI_TIME_STAMP, &opt, sizeof(opt)) < 0) {
pcap_fmt_errmsg_for_errno(handle->errbuf, PCAP_ERRBUF_SIZE,
errno, "Can't enable time stamp");
goto close_fail;
}
/* Setup filter, do not call hci function to avoid dependence on
* external libs */
memset(&flt, 0, sizeof(flt));
memset((void *) &flt.type_mask, 0xff, sizeof(flt.type_mask));
memset((void *) &flt.event_mask, 0xff, sizeof(flt.event_mask));
if (setsockopt(handle->fd, SOL_HCI, HCI_FILTER, &flt, sizeof(flt)) < 0) {
pcap_fmt_errmsg_for_errno(handle->errbuf, PCAP_ERRBUF_SIZE,
errno, "Can't set filter");
goto close_fail;
}
/* Bind socket to the HCI device */
addr.hci_family = AF_BLUETOOTH;
addr.hci_dev = handlep->dev_id;
#ifdef HAVE_STRUCT_SOCKADDR_HCI_HCI_CHANNEL
addr.hci_channel = HCI_CHANNEL_RAW;
#endif
if (bind(handle->fd, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
pcap_fmt_errmsg_for_errno(handle->errbuf, PCAP_ERRBUF_SIZE,
errno, "Can't attach to device %d", handlep->dev_id);
goto close_fail;
}
if (handle->opt.rfmon) {
/*
* Monitor mode doesn't apply to Bluetooth devices.
*/
err = PCAP_ERROR_RFMON_NOTSUP;
goto close_fail;
}
if (handle->opt.buffer_size != 0) {
/*
* Set the socket buffer size to the specified value.
*/
if (setsockopt(handle->fd, SOL_SOCKET, SO_RCVBUF,
&handle->opt.buffer_size,
sizeof(handle->opt.buffer_size)) == -1) {
pcap_fmt_errmsg_for_errno(handle->errbuf,
errno, PCAP_ERRBUF_SIZE, "SO_RCVBUF");
goto close_fail;
}
}
handle->selectable_fd = handle->fd;
return 0;
close_fail:
pcap_cleanup_live_common(handle);
return err;
}
static int
bt_read_linux(pcap_t *handle, int max_packets _U_, pcap_handler callback, u_char *user)
{
struct cmsghdr *cmsg;
struct msghdr msg;
struct iovec iv;
ssize_t ret;
struct pcap_pkthdr pkth;
pcap_bluetooth_h4_header* bthdr;
u_char *pktd;
int in = 0;
pktd = (u_char *)handle->buffer + BT_CTRL_SIZE;
bthdr = (pcap_bluetooth_h4_header*)(void *)pktd;
iv.iov_base = pktd + sizeof(pcap_bluetooth_h4_header);
iv.iov_len = handle->snapshot;
memset(&msg, 0, sizeof(msg));
msg.msg_iov = &iv;
msg.msg_iovlen = 1;
msg.msg_control = handle->buffer;
msg.msg_controllen = BT_CTRL_SIZE;
/* ignore interrupt system call error */
do {
ret = recvmsg(handle->fd, &msg, 0);
if (handle->break_loop)
{
handle->break_loop = 0;
return -2;
}
} while ((ret == -1) && (errno == EINTR));
if (ret < 0) {
pcap_fmt_errmsg_for_errno(handle->errbuf, PCAP_ERRBUF_SIZE,
errno, "Can't receive packet");
return -1;
}
pkth.caplen = ret;
/* get direction and timestamp*/
cmsg = CMSG_FIRSTHDR(&msg);
while (cmsg) {
switch (cmsg->cmsg_type) {
case HCI_CMSG_DIR:
memcpy(&in, CMSG_DATA(cmsg), sizeof in);
break;
case HCI_CMSG_TSTAMP:
memcpy(&pkth.ts, CMSG_DATA(cmsg),
sizeof pkth.ts);
break;
}
cmsg = CMSG_NXTHDR(&msg, cmsg);
}
if ((in && (handle->direction == PCAP_D_OUT)) ||
((!in) && (handle->direction == PCAP_D_IN)))
return 0;
bthdr->direction = htonl(in != 0);
pkth.caplen+=sizeof(pcap_bluetooth_h4_header);
pkth.len = pkth.caplen;
if (handle->fcode.bf_insns == NULL ||
bpf_filter(handle->fcode.bf_insns, pktd, pkth.len, pkth.caplen)) {
callback(user, &pkth, pktd);
return 1;
}
return 0; /* didn't pass filter */
}
static int
bt_inject_linux(pcap_t *handle, const void *buf _U_, size_t size _U_)
{
pcap_snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "inject not supported on "
"bluetooth devices");
return (-1);
}
static int
bt_stats_linux(pcap_t *handle, struct pcap_stat *stats)
{
struct pcap_bt *handlep = handle->priv;
int ret;
struct hci_dev_info dev_info;
struct hci_dev_stats * s = &dev_info.stat;
dev_info.dev_id = handlep->dev_id;
/* ignore eintr */
do {
ret = ioctl(handle->fd, HCIGETDEVINFO, (void *)&dev_info);
} while ((ret == -1) && (errno == EINTR));
if (ret < 0) {
pcap_fmt_errmsg_for_errno(handle->errbuf, PCAP_ERRBUF_SIZE,
errno, "Can't get stats via ioctl");
return (-1);
}
/* we receive both rx and tx frames, so comulate all stats */
stats->ps_recv = s->evt_rx + s->acl_rx + s->sco_rx + s->cmd_tx +
s->acl_tx +s->sco_tx;
stats->ps_drop = s->err_rx + s->err_tx;
stats->ps_ifdrop = 0;
return 0;
}
static int
bt_setdirection_linux(pcap_t *p, pcap_direction_t d)
{
p->direction = d;
return 0;
}