1 |
|
|
/* $OpenBSD: pcap-bpf.c,v 1.35 2017/04/19 05:36:12 natano Exp $ */ |
2 |
|
|
|
3 |
|
|
/* |
4 |
|
|
* Copyright (c) 1993, 1994, 1995, 1996, 1998 |
5 |
|
|
* The Regents of the University of California. All rights reserved. |
6 |
|
|
* |
7 |
|
|
* Redistribution and use in source and binary forms, with or without |
8 |
|
|
* modification, are permitted provided that: (1) source code distributions |
9 |
|
|
* retain the above copyright notice and this paragraph in its entirety, (2) |
10 |
|
|
* distributions including binary code include the above copyright notice and |
11 |
|
|
* this paragraph in its entirety in the documentation or other materials |
12 |
|
|
* provided with the distribution, and (3) all advertising materials mentioning |
13 |
|
|
* features or use of this software display the following acknowledgement: |
14 |
|
|
* ``This product includes software developed by the University of California, |
15 |
|
|
* Lawrence Berkeley Laboratory and its contributors.'' Neither the name of |
16 |
|
|
* the University nor the names of its contributors may be used to endorse |
17 |
|
|
* or promote products derived from this software without specific prior |
18 |
|
|
* written permission. |
19 |
|
|
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED |
20 |
|
|
* WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF |
21 |
|
|
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. |
22 |
|
|
*/ |
23 |
|
|
|
24 |
|
|
#include <sys/param.h> /* optionally get BSD define */ |
25 |
|
|
#include <sys/time.h> |
26 |
|
|
#include <sys/socket.h> |
27 |
|
|
#include <sys/ioctl.h> |
28 |
|
|
|
29 |
|
|
#include <net/if.h> |
30 |
|
|
|
31 |
|
|
#include <ctype.h> |
32 |
|
|
#include <errno.h> |
33 |
|
|
#include <fcntl.h> |
34 |
|
|
#include <netdb.h> |
35 |
|
|
#include <stdio.h> |
36 |
|
|
#include <stdlib.h> |
37 |
|
|
#include <string.h> |
38 |
|
|
#include <unistd.h> |
39 |
|
|
|
40 |
|
|
#include <net/if_media.h> |
41 |
|
|
|
42 |
|
|
#include "pcap-int.h" |
43 |
|
|
|
44 |
|
|
#ifdef HAVE_OS_PROTO_H |
45 |
|
|
#include "os-proto.h" |
46 |
|
|
#endif |
47 |
|
|
|
48 |
|
|
#include "gencode.h" |
49 |
|
|
|
50 |
|
|
static int find_802_11(struct bpf_dltlist *); |
51 |
|
|
static int monitor_mode(pcap_t *, int); |
52 |
|
|
|
53 |
|
|
int |
54 |
|
|
pcap_stats(pcap_t *p, struct pcap_stat *ps) |
55 |
|
|
{ |
56 |
|
|
struct bpf_stat s; |
57 |
|
|
|
58 |
|
|
if (ioctl(p->fd, BIOCGSTATS, (caddr_t)&s) < 0) { |
59 |
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCGSTATS: %s", |
60 |
|
|
pcap_strerror(errno)); |
61 |
|
|
return (PCAP_ERROR); |
62 |
|
|
} |
63 |
|
|
|
64 |
|
|
ps->ps_recv = s.bs_recv; |
65 |
|
|
ps->ps_drop = s.bs_drop; |
66 |
|
|
return (0); |
67 |
|
|
} |
68 |
|
|
|
69 |
|
|
int |
70 |
|
|
pcap_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user) |
71 |
|
|
{ |
72 |
|
|
int cc; |
73 |
|
|
int n = 0; |
74 |
|
42 |
u_char *bp, *ep; |
75 |
|
|
|
76 |
|
|
again: |
77 |
|
|
/* |
78 |
|
|
* Has "pcap_breakloop()" been called? |
79 |
|
|
*/ |
80 |
✗✓ |
21 |
if (p->break_loop) { |
81 |
|
|
/* |
82 |
|
|
* Yes - clear the flag that indicates that it |
83 |
|
|
* has, and return PCAP_ERROR_BREAK to indicate |
84 |
|
|
* that we were told to break out of the loop. |
85 |
|
|
*/ |
86 |
|
|
p->break_loop = 0; |
87 |
|
|
return (PCAP_ERROR_BREAK); |
88 |
|
|
} |
89 |
|
|
|
90 |
|
21 |
cc = p->cc; |
91 |
✓✗ |
21 |
if (p->cc == 0) { |
92 |
|
21 |
cc = read(p->fd, (char *)p->buffer, p->bufsize); |
93 |
✗✓ |
21 |
if (cc < 0) { |
94 |
|
|
/* Don't choke when we get ptraced */ |
95 |
|
|
switch (errno) { |
96 |
|
|
|
97 |
|
|
case EINTR: |
98 |
|
|
goto again; |
99 |
|
|
|
100 |
|
|
case EWOULDBLOCK: |
101 |
|
|
return (0); |
102 |
|
|
|
103 |
|
|
case ENXIO: |
104 |
|
|
/* |
105 |
|
|
* The device on which we're capturing |
106 |
|
|
* went away. |
107 |
|
|
* |
108 |
|
|
* XXX - we should really return |
109 |
|
|
* PCAP_ERROR_IFACE_NOT_UP, but |
110 |
|
|
* pcap_dispatch() etc. aren't |
111 |
|
|
* defined to return that. |
112 |
|
|
*/ |
113 |
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
114 |
|
|
"The interface went down"); |
115 |
|
|
return (PCAP_ERROR); |
116 |
|
|
|
117 |
|
|
#if defined(sun) && !defined(BSD) |
118 |
|
|
/* |
119 |
|
|
* Due to a SunOS bug, after 2^31 bytes, the kernel |
120 |
|
|
* file offset overflows and read fails with EINVAL. |
121 |
|
|
* The lseek() to 0 will fix things. |
122 |
|
|
*/ |
123 |
|
|
case EINVAL: |
124 |
|
|
if (lseek(p->fd, 0L, SEEK_CUR) + |
125 |
|
|
p->bufsize < 0) { |
126 |
|
|
(void)lseek(p->fd, 0L, SEEK_SET); |
127 |
|
|
goto again; |
128 |
|
|
} |
129 |
|
|
/* FALLTHROUGH */ |
130 |
|
|
#endif |
131 |
|
|
} |
132 |
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "read: %s", |
133 |
|
|
pcap_strerror(errno)); |
134 |
|
|
return (PCAP_ERROR); |
135 |
|
|
} |
136 |
|
21 |
bp = p->buffer; |
137 |
|
21 |
} else |
138 |
|
|
bp = p->bp; |
139 |
|
|
|
140 |
|
|
/* |
141 |
|
|
* Loop through each packet. |
142 |
|
|
*/ |
143 |
|
|
#define bhp ((struct bpf_hdr *)bp) |
144 |
|
21 |
ep = bp + cc; |
145 |
✓✓ |
54 |
while (bp < ep) { |
146 |
|
|
int caplen, hdrlen; |
147 |
|
|
|
148 |
|
|
/* |
149 |
|
|
* Has "pcap_breakloop()" been called? |
150 |
|
|
* If so, return immediately - if we haven't read any |
151 |
|
|
* packets, clear the flag and return PCAP_ERROR_BREAK |
152 |
|
|
* to indicate that we were told to break out of the loop, |
153 |
|
|
* otherwise leave the flag set, so that the *next* call |
154 |
|
|
* will break out of the loop without having read any |
155 |
|
|
* packets, and return the number of packets we've |
156 |
|
|
* processed so far. |
157 |
|
|
*/ |
158 |
✗✓ |
12 |
if (p->break_loop) { |
159 |
|
|
p->bp = bp; |
160 |
|
|
p->cc = ep - bp; |
161 |
|
|
/* |
162 |
|
|
* ep is set based on the return value of read(), |
163 |
|
|
* but read() from a BPF device doesn't necessarily |
164 |
|
|
* return a value that's a multiple of the alignment |
165 |
|
|
* value for BPF_WORDALIGN(). However, whenever we |
166 |
|
|
* increment bp, we round up the increment value by |
167 |
|
|
* a value rounded up by BPF_WORDALIGN(), so we |
168 |
|
|
* could increment bp past ep after processing the |
169 |
|
|
* last packet in the buffer. |
170 |
|
|
* |
171 |
|
|
* We treat ep < bp as an indication that this |
172 |
|
|
* happened, and just set p->cc to 0. |
173 |
|
|
*/ |
174 |
|
|
if (p->cc < 0) |
175 |
|
|
p->cc = 0; |
176 |
|
|
if (n == 0) { |
177 |
|
|
p->break_loop = 0; |
178 |
|
|
return (PCAP_ERROR_BREAK); |
179 |
|
|
} else |
180 |
|
|
return (n); |
181 |
|
|
} |
182 |
|
|
|
183 |
|
12 |
caplen = bhp->bh_caplen; |
184 |
|
12 |
hdrlen = bhp->bh_hdrlen; |
185 |
|
|
/* |
186 |
|
|
* XXX A bpf_hdr matches a pcap_pkthdr. |
187 |
|
|
*/ |
188 |
|
12 |
(*callback)(user, (struct pcap_pkthdr*)bp, bp + hdrlen); |
189 |
|
12 |
bp += BPF_WORDALIGN(caplen + hdrlen); |
190 |
✓✓ |
12 |
if (++n >= cnt && cnt > 0) { |
191 |
|
6 |
p->bp = bp; |
192 |
|
6 |
p->cc = ep - bp; |
193 |
|
6 |
return (n); |
194 |
|
|
} |
195 |
✓✓ |
6 |
} |
196 |
|
|
#undef bhp |
197 |
|
15 |
p->cc = 0; |
198 |
|
15 |
return (n); |
199 |
|
21 |
} |
200 |
|
|
|
201 |
|
|
int |
202 |
|
|
pcap_inject(pcap_t *p, const void *buf, size_t len) |
203 |
|
|
{ |
204 |
|
|
return (write(p->fd, buf, len)); |
205 |
|
|
} |
206 |
|
|
|
207 |
|
|
int |
208 |
|
|
pcap_sendpacket(pcap_t *p, const u_char *buf, int size) |
209 |
|
|
{ |
210 |
|
|
return (pcap_inject(p, buf, size) == -1 ? -1 : 0); |
211 |
|
|
} |
212 |
|
|
|
213 |
|
|
/* ARGSUSED */ |
214 |
|
|
static __inline int |
215 |
|
|
bpf_open(pcap_t *p) |
216 |
|
|
{ |
217 |
|
|
int fd; |
218 |
|
|
|
219 |
|
18 |
fd = open("/dev/bpf", O_RDWR); |
220 |
✗✓✗✗
|
9 |
if (fd == -1 && errno == EACCES) |
221 |
|
|
fd = open("/dev/bpf", O_RDONLY); |
222 |
|
|
|
223 |
✗✓ |
9 |
if (fd == -1) { |
224 |
|
|
if (errno == EACCES) |
225 |
|
|
fd = PCAP_ERROR_PERM_DENIED; |
226 |
|
|
else |
227 |
|
|
fd = PCAP_ERROR; |
228 |
|
|
|
229 |
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
230 |
|
|
"(cannot open BPF device): %s", |
231 |
|
|
pcap_strerror(errno)); |
232 |
|
|
} |
233 |
|
|
|
234 |
|
9 |
return (fd); |
235 |
|
|
} |
236 |
|
|
|
237 |
|
|
static int |
238 |
|
|
get_dlt_list(int fd, int v, struct bpf_dltlist *bdlp, char *ebuf) |
239 |
|
|
{ |
240 |
|
18 |
memset(bdlp, 0, sizeof(*bdlp)); |
241 |
✓✗ |
9 |
if (ioctl(fd, BIOCGDLTLIST, (caddr_t)bdlp) == 0) { |
242 |
|
9 |
bdlp->bfl_list = calloc(bdlp->bfl_len + 1, sizeof(u_int)); |
243 |
✗✓ |
9 |
if (bdlp->bfl_list == NULL) { |
244 |
|
|
(void)snprintf(ebuf, PCAP_ERRBUF_SIZE, "malloc: %s", |
245 |
|
|
pcap_strerror(errno)); |
246 |
|
|
return (PCAP_ERROR); |
247 |
|
|
} |
248 |
|
|
|
249 |
✗✓ |
9 |
if (ioctl(fd, BIOCGDLTLIST, (caddr_t)bdlp) < 0) { |
250 |
|
|
(void)snprintf(ebuf, PCAP_ERRBUF_SIZE, |
251 |
|
|
"BIOCGDLTLIST: %s", pcap_strerror(errno)); |
252 |
|
|
free(bdlp->bfl_list); |
253 |
|
|
return (PCAP_ERROR); |
254 |
|
|
} |
255 |
|
|
} else { |
256 |
|
|
/* |
257 |
|
|
* EINVAL just means "we don't support this ioctl on |
258 |
|
|
* this device"; don't treat it as an error. |
259 |
|
|
*/ |
260 |
|
|
if (errno != EINVAL) { |
261 |
|
|
(void)snprintf(ebuf, PCAP_ERRBUF_SIZE, |
262 |
|
|
"BIOCGDLTLIST: %s", pcap_strerror(errno)); |
263 |
|
|
return (PCAP_ERROR); |
264 |
|
|
} |
265 |
|
|
} |
266 |
|
9 |
return (0); |
267 |
|
9 |
} |
268 |
|
|
|
269 |
|
|
/* |
270 |
|
|
* Returns 1 if rfmon mode can be set on the pcap_t, 0 if it can't, |
271 |
|
|
* a PCAP_ERROR value on an error. |
272 |
|
|
*/ |
273 |
|
|
int |
274 |
|
|
pcap_can_set_rfmon(pcap_t *p) |
275 |
|
|
{ |
276 |
|
|
#if defined(HAVE_BSD_IEEE80211) |
277 |
|
|
int ret; |
278 |
|
|
|
279 |
|
|
ret = monitor_mode(p, 0); |
280 |
|
|
if (ret == PCAP_ERROR_RFMON_NOTSUP) |
281 |
|
|
return (0); /* not an error, just a "can't do" */ |
282 |
|
|
if (ret == 0) |
283 |
|
|
return (1); /* success */ |
284 |
|
|
return (ret); |
285 |
|
|
#else |
286 |
|
|
return (0); |
287 |
|
|
#endif |
288 |
|
|
} |
289 |
|
|
|
290 |
|
|
static void |
291 |
|
|
pcap_cleanup_bpf(pcap_t *p) |
292 |
|
|
{ |
293 |
|
|
#ifdef HAVE_BSD_IEEE80211 |
294 |
|
|
int sock; |
295 |
|
8 |
struct ifmediareq req; |
296 |
|
4 |
struct ifreq ifr; |
297 |
|
|
#endif |
298 |
|
|
|
299 |
✗✓ |
4 |
if (p->md.must_do_on_close != 0) { |
300 |
|
|
/* |
301 |
|
|
* There's something we have to do when closing this |
302 |
|
|
* pcap_t. |
303 |
|
|
*/ |
304 |
|
|
#ifdef HAVE_BSD_IEEE80211 |
305 |
|
|
if (p->md.must_do_on_close & MUST_CLEAR_RFMON) { |
306 |
|
|
/* |
307 |
|
|
* We put the interface into rfmon mode; |
308 |
|
|
* take it out of rfmon mode. |
309 |
|
|
* |
310 |
|
|
* XXX - if somebody else wants it in rfmon |
311 |
|
|
* mode, this code cannot know that, so it'll take |
312 |
|
|
* it out of rfmon mode. |
313 |
|
|
*/ |
314 |
|
|
sock = socket(AF_INET, SOCK_DGRAM, 0); |
315 |
|
|
if (sock == -1) { |
316 |
|
|
fprintf(stderr, |
317 |
|
|
"Can't restore interface flags (socket() failed: %s).\n" |
318 |
|
|
"Please adjust manually.\n", |
319 |
|
|
strerror(errno)); |
320 |
|
|
} else { |
321 |
|
|
memset(&req, 0, sizeof(req)); |
322 |
|
|
(void)strlcpy(req.ifm_name, p->opt.source, |
323 |
|
|
sizeof(req.ifm_name)); |
324 |
|
|
if (ioctl(sock, SIOCGIFMEDIA, &req) < 0) { |
325 |
|
|
fprintf(stderr, |
326 |
|
|
"Can't restore interface flags " |
327 |
|
|
"(SIOCGIFMEDIA failed: %s).\n" |
328 |
|
|
"Please adjust manually.\n", |
329 |
|
|
strerror(errno)); |
330 |
|
|
} else if (req.ifm_current & IFM_IEEE80211_MONITOR) { |
331 |
|
|
/* |
332 |
|
|
* Rfmon mode is currently on; |
333 |
|
|
* turn it off. |
334 |
|
|
*/ |
335 |
|
|
memset(&ifr, 0, sizeof(ifr)); |
336 |
|
|
(void)strlcpy(ifr.ifr_name, |
337 |
|
|
p->opt.source, |
338 |
|
|
sizeof(ifr.ifr_name)); |
339 |
|
|
ifr.ifr_media = |
340 |
|
|
req.ifm_current & ~IFM_IEEE80211_MONITOR; |
341 |
|
|
if (ioctl(sock, SIOCSIFMEDIA, |
342 |
|
|
&ifr) == -1) { |
343 |
|
|
fprintf(stderr, |
344 |
|
|
"Can't restore interface flags " |
345 |
|
|
"(SIOCSIFMEDIA failed: %s).\n" |
346 |
|
|
"Please adjust manually.\n", |
347 |
|
|
strerror(errno)); |
348 |
|
|
} |
349 |
|
|
} |
350 |
|
|
close(sock); |
351 |
|
|
} |
352 |
|
|
} |
353 |
|
|
#endif /* HAVE_BSD_IEEE80211 */ |
354 |
|
|
|
355 |
|
|
/* |
356 |
|
|
* Take this pcap out of the list of pcaps for which we |
357 |
|
|
* have to take the interface out of some mode. |
358 |
|
|
*/ |
359 |
|
|
pcap_remove_from_pcaps_to_close(p); |
360 |
|
|
p->md.must_do_on_close = 0; |
361 |
|
|
} |
362 |
|
|
|
363 |
|
|
/*XXX*/ |
364 |
✗✓ |
4 |
if (p->fd >= 0) { |
365 |
|
|
close(p->fd); |
366 |
|
|
p->fd = -1; |
367 |
|
|
} |
368 |
✓✗ |
4 |
if (p->sf.rfile != NULL) { |
369 |
|
4 |
(void)fclose(p->sf.rfile); |
370 |
|
4 |
free(p->sf.base); |
371 |
|
4 |
} else |
372 |
|
|
free(p->buffer); |
373 |
|
|
|
374 |
|
4 |
pcap_freecode(&p->fcode); |
375 |
✗✓ |
4 |
if (p->dlt_list != NULL) { |
376 |
|
|
free(p->dlt_list); |
377 |
|
|
p->dlt_list = NULL; |
378 |
|
|
p->dlt_count = 0; |
379 |
|
|
} |
380 |
|
4 |
} |
381 |
|
|
|
382 |
|
|
void |
383 |
|
|
pcap_close(pcap_t *p) |
384 |
|
|
{ |
385 |
|
8 |
pcap_cleanup_bpf(p); |
386 |
|
4 |
free(p->opt.source); |
387 |
|
4 |
free(p); |
388 |
|
4 |
} |
389 |
|
|
|
390 |
|
|
|
391 |
|
|
static int |
392 |
|
|
check_setif_failure(pcap_t *p, int error) |
393 |
|
|
{ |
394 |
|
|
if (error == ENXIO) { |
395 |
|
|
/* |
396 |
|
|
* No such device. |
397 |
|
|
*/ |
398 |
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCSETIF failed: %s", |
399 |
|
|
pcap_strerror(errno)); |
400 |
|
|
return (PCAP_ERROR_NO_SUCH_DEVICE); |
401 |
|
|
} else if (errno == ENETDOWN) { |
402 |
|
|
/* |
403 |
|
|
* Return a "network down" indication, so that |
404 |
|
|
* the application can report that rather than |
405 |
|
|
* saying we had a mysterious failure and |
406 |
|
|
* suggest that they report a problem to the |
407 |
|
|
* libpcap developers. |
408 |
|
|
*/ |
409 |
|
|
return (PCAP_ERROR_IFACE_NOT_UP); |
410 |
|
|
} else { |
411 |
|
|
/* |
412 |
|
|
* Some other error; fill in the error string, and |
413 |
|
|
* return PCAP_ERROR. |
414 |
|
|
*/ |
415 |
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCSETIF: %s: %s", |
416 |
|
|
p->opt.source, pcap_strerror(errno)); |
417 |
|
|
return (PCAP_ERROR); |
418 |
|
|
} |
419 |
|
|
} |
420 |
|
|
|
421 |
|
|
int |
422 |
|
|
pcap_activate(pcap_t *p) |
423 |
|
|
{ |
424 |
|
|
int status = 0; |
425 |
|
|
int fd; |
426 |
|
18 |
struct ifreq ifr; |
427 |
|
9 |
struct bpf_version bv; |
428 |
|
9 |
struct bpf_dltlist bdl; |
429 |
|
9 |
int new_dlt; |
430 |
|
9 |
u_int v; |
431 |
|
|
|
432 |
|
9 |
fd = bpf_open(p); |
433 |
✗✓ |
9 |
if (fd < 0) { |
434 |
|
|
status = fd; |
435 |
|
|
goto bad; |
436 |
|
|
} |
437 |
|
|
|
438 |
|
9 |
p->fd = fd; |
439 |
|
|
|
440 |
✗✓ |
9 |
if (ioctl(fd, BIOCVERSION, (caddr_t)&bv) < 0) { |
441 |
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCVERSION: %s", |
442 |
|
|
pcap_strerror(errno)); |
443 |
|
|
status = PCAP_ERROR; |
444 |
|
|
goto bad; |
445 |
|
|
} |
446 |
✓✗✗✓
|
18 |
if (bv.bv_major != BPF_MAJOR_VERSION || |
447 |
|
9 |
bv.bv_minor < BPF_MINOR_VERSION) { |
448 |
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
449 |
|
|
"kernel bpf filter out of date"); |
450 |
|
|
status = PCAP_ERROR; |
451 |
|
|
goto bad; |
452 |
|
|
} |
453 |
|
|
|
454 |
|
|
#if 0 |
455 |
|
|
/* Just use the kernel default */ |
456 |
|
|
v = 32768; /* XXX this should be a user-accessible hook */ |
457 |
|
|
/* Ignore the return value - this is because the call fails on |
458 |
|
|
* BPF systems that don't have kernel malloc. And if the call |
459 |
|
|
* fails, it's no big deal, we just continue to use the standard |
460 |
|
|
* buffer size. |
461 |
|
|
*/ |
462 |
|
|
(void) ioctl(fd, BIOCSBLEN, (caddr_t)&v); |
463 |
|
|
#endif |
464 |
|
|
|
465 |
|
|
/* |
466 |
|
|
* Set the buffer size. |
467 |
|
|
*/ |
468 |
✗✓ |
9 |
if (p->opt.buffer_size != 0) { |
469 |
|
|
/* |
470 |
|
|
* A buffer size was explicitly specified; use it. |
471 |
|
|
*/ |
472 |
|
|
if (ioctl(fd, BIOCSBLEN, |
473 |
|
|
(caddr_t)&p->opt.buffer_size) < 0) { |
474 |
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
475 |
|
|
"BIOCSBLEN: %s: %s", p->opt.source, |
476 |
|
|
pcap_strerror(errno)); |
477 |
|
|
status = PCAP_ERROR; |
478 |
|
|
goto bad; |
479 |
|
|
} |
480 |
|
|
} |
481 |
|
|
|
482 |
|
|
/* |
483 |
|
|
* Now bind to the device. |
484 |
|
|
*/ |
485 |
|
9 |
(void)strlcpy(ifr.ifr_name, p->opt.source, sizeof(ifr.ifr_name)); |
486 |
✗✓ |
9 |
if (ioctl(fd, BIOCSETIF, (caddr_t)&ifr) < 0) { |
487 |
|
|
status = check_setif_failure(p, errno); |
488 |
|
|
goto bad; |
489 |
|
|
} |
490 |
|
|
/* Get the data link layer type. */ |
491 |
✗✓ |
9 |
if (ioctl(fd, BIOCGDLT, (caddr_t)&v) < 0) { |
492 |
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCGDLT: %s", |
493 |
|
|
pcap_strerror(errno)); |
494 |
|
|
status = PCAP_ERROR; |
495 |
|
|
goto bad; |
496 |
|
|
} |
497 |
|
|
|
498 |
|
|
/* |
499 |
|
|
* We know the default link type -- now determine all the DLTs |
500 |
|
|
* this interface supports. If this fails with EINVAL, it's |
501 |
|
|
* not fatal; we just don't get to use the feature later. |
502 |
|
|
*/ |
503 |
✗✓ |
9 |
if (get_dlt_list(fd, v, &bdl, p->errbuf) == -1) { |
504 |
|
|
status = PCAP_ERROR; |
505 |
|
|
goto bad; |
506 |
|
|
} |
507 |
|
9 |
p->dlt_count = bdl.bfl_len; |
508 |
|
9 |
p->dlt_list = bdl.bfl_list; |
509 |
|
|
|
510 |
|
|
/* |
511 |
|
|
* *BSD with the new 802.11 ioctls. |
512 |
|
|
* Do we want monitor mode? |
513 |
|
|
*/ |
514 |
✗✓ |
9 |
if (p->opt.rfmon) { |
515 |
|
|
/* |
516 |
|
|
* Try to put the interface into monitor mode. |
517 |
|
|
*/ |
518 |
|
|
status = monitor_mode(p, 1); |
519 |
|
|
if (status != 0) { |
520 |
|
|
/* |
521 |
|
|
* We failed. |
522 |
|
|
*/ |
523 |
|
|
goto bad; |
524 |
|
|
} |
525 |
|
|
|
526 |
|
|
/* |
527 |
|
|
* We're in monitor mode. |
528 |
|
|
* Try to find the best 802.11 DLT_ value and, if we |
529 |
|
|
* succeed, try to switch to that mode if we're not |
530 |
|
|
* already in that mode. |
531 |
|
|
*/ |
532 |
|
|
new_dlt = find_802_11(&bdl); |
533 |
|
|
if (new_dlt != -1) { |
534 |
|
|
/* |
535 |
|
|
* We have at least one 802.11 DLT_ value. |
536 |
|
|
* new_dlt is the best of the 802.11 |
537 |
|
|
* DLT_ values in the list. |
538 |
|
|
* |
539 |
|
|
* If the new mode we want isn't the default mode, |
540 |
|
|
* attempt to select the new mode. |
541 |
|
|
*/ |
542 |
|
|
if (new_dlt != v) { |
543 |
|
|
if (ioctl(p->fd, BIOCSDLT, &new_dlt) != -1) { |
544 |
|
|
/* |
545 |
|
|
* We succeeded; make this the |
546 |
|
|
* new DLT_ value. |
547 |
|
|
*/ |
548 |
|
|
v = new_dlt; |
549 |
|
|
} |
550 |
|
|
} |
551 |
|
|
} |
552 |
|
|
} |
553 |
|
9 |
p->linktype = v; |
554 |
|
|
|
555 |
|
|
/* set timeout */ |
556 |
✓✓ |
9 |
if (p->md.timeout) { |
557 |
|
6 |
struct timeval to; |
558 |
|
6 |
to.tv_sec = p->md.timeout / 1000; |
559 |
|
6 |
to.tv_usec = (p->md.timeout * 1000) % 1000000; |
560 |
✗✓ |
6 |
if (ioctl(p->fd, BIOCSRTIMEOUT, (caddr_t)&to) < 0) { |
561 |
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
562 |
|
|
"BIOCSRTIMEOUT: %s", pcap_strerror(errno)); |
563 |
|
|
status = PCAP_ERROR; |
564 |
|
|
goto bad; |
565 |
|
|
} |
566 |
✓✗✓ |
18 |
} |
567 |
|
|
|
568 |
✓✓ |
9 |
if (p->opt.promisc) { |
569 |
|
|
/* set promiscuous mode, just warn if it fails */ |
570 |
✗✓ |
3 |
if (ioctl(p->fd, BIOCPROMISC, NULL) < 0) { |
571 |
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCPROMISC: %s", |
572 |
|
|
pcap_strerror(errno)); |
573 |
|
|
status = PCAP_WARNING_PROMISC_NOTSUP; |
574 |
|
|
} |
575 |
|
|
} |
576 |
|
|
|
577 |
✗✓ |
9 |
if (ioctl(fd, BIOCGBLEN, (caddr_t)&v) < 0) { |
578 |
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCGBLEN: %s", |
579 |
|
|
pcap_strerror(errno)); |
580 |
|
|
status = PCAP_ERROR; |
581 |
|
|
goto bad; |
582 |
|
|
} |
583 |
|
9 |
p->bufsize = v; |
584 |
|
9 |
p->buffer = malloc(p->bufsize); |
585 |
✗✓ |
9 |
if (p->buffer == NULL) { |
586 |
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "malloc: %s", |
587 |
|
|
pcap_strerror(errno)); |
588 |
|
|
status = PCAP_ERROR; |
589 |
|
|
goto bad; |
590 |
|
|
} |
591 |
|
|
|
592 |
✓✗ |
9 |
if (status < 0) |
593 |
|
|
goto bad; |
594 |
|
|
|
595 |
|
9 |
p->activated = 1; |
596 |
|
|
|
597 |
|
9 |
return (status); |
598 |
|
|
bad: |
599 |
|
|
pcap_cleanup_bpf(p); |
600 |
|
|
|
601 |
|
|
if (p->errbuf[0] == '\0') { |
602 |
|
|
/* |
603 |
|
|
* No error message supplied by the activate routine; |
604 |
|
|
* for the benefit of programs that don't specially |
605 |
|
|
* handle errors other than PCAP_ERROR, return the |
606 |
|
|
* error message corresponding to the status. |
607 |
|
|
*/ |
608 |
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "%s", |
609 |
|
|
pcap_statustostr(status)); |
610 |
|
|
} |
611 |
|
|
|
612 |
|
|
return (status); |
613 |
|
9 |
} |
614 |
|
|
|
615 |
|
|
static int |
616 |
|
|
monitor_mode(pcap_t *p, int set) |
617 |
|
|
{ |
618 |
|
|
int sock; |
619 |
|
|
struct ifmediareq req; |
620 |
|
|
uint64_t *media_list; |
621 |
|
|
int i; |
622 |
|
|
int can_do; |
623 |
|
|
struct ifreq ifr; |
624 |
|
|
|
625 |
|
|
sock = socket(AF_INET, SOCK_DGRAM, 0); |
626 |
|
|
if (sock == -1) { |
627 |
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "can't open socket: %s", |
628 |
|
|
pcap_strerror(errno)); |
629 |
|
|
return (PCAP_ERROR); |
630 |
|
|
} |
631 |
|
|
|
632 |
|
|
memset(&req, 0, sizeof req); |
633 |
|
|
(void)strlcpy(req.ifm_name, p->opt.source, sizeof req.ifm_name); |
634 |
|
|
|
635 |
|
|
/* |
636 |
|
|
* Find out how many media types we have. |
637 |
|
|
*/ |
638 |
|
|
if (ioctl(sock, SIOCGIFMEDIA, &req) < 0) { |
639 |
|
|
/* |
640 |
|
|
* Can't get the media types. |
641 |
|
|
*/ |
642 |
|
|
switch (errno) { |
643 |
|
|
|
644 |
|
|
case ENXIO: |
645 |
|
|
/* |
646 |
|
|
* There's no such device. |
647 |
|
|
*/ |
648 |
|
|
close(sock); |
649 |
|
|
return (PCAP_ERROR_NO_SUCH_DEVICE); |
650 |
|
|
|
651 |
|
|
case EINVAL: |
652 |
|
|
case ENOTTY: |
653 |
|
|
/* |
654 |
|
|
* Interface doesn't support SIOC{G,S}IFMEDIA. |
655 |
|
|
*/ |
656 |
|
|
close(sock); |
657 |
|
|
return (PCAP_ERROR_RFMON_NOTSUP); |
658 |
|
|
|
659 |
|
|
default: |
660 |
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
661 |
|
|
"SIOCGIFMEDIA 1: %s", pcap_strerror(errno)); |
662 |
|
|
close(sock); |
663 |
|
|
return (PCAP_ERROR); |
664 |
|
|
} |
665 |
|
|
} |
666 |
|
|
if (req.ifm_count == 0) { |
667 |
|
|
/* |
668 |
|
|
* No media types. |
669 |
|
|
*/ |
670 |
|
|
close(sock); |
671 |
|
|
return (PCAP_ERROR_RFMON_NOTSUP); |
672 |
|
|
} |
673 |
|
|
|
674 |
|
|
/* |
675 |
|
|
* Allocate a buffer to hold all the media types, and |
676 |
|
|
* get the media types. |
677 |
|
|
*/ |
678 |
|
|
media_list = calloc(req.ifm_count, sizeof(*media_list)); |
679 |
|
|
if (media_list == NULL) { |
680 |
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "malloc: %s", |
681 |
|
|
pcap_strerror(errno)); |
682 |
|
|
close(sock); |
683 |
|
|
return (PCAP_ERROR); |
684 |
|
|
} |
685 |
|
|
req.ifm_ulist = media_list; |
686 |
|
|
if (ioctl(sock, SIOCGIFMEDIA, &req) < 0) { |
687 |
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "SIOCGIFMEDIA: %s", |
688 |
|
|
pcap_strerror(errno)); |
689 |
|
|
free(media_list); |
690 |
|
|
close(sock); |
691 |
|
|
return (PCAP_ERROR); |
692 |
|
|
} |
693 |
|
|
|
694 |
|
|
/* |
695 |
|
|
* Look for an 802.11 "automatic" media type. |
696 |
|
|
* We assume that all 802.11 adapters have that media type, |
697 |
|
|
* and that it will carry the monitor mode supported flag. |
698 |
|
|
*/ |
699 |
|
|
can_do = 0; |
700 |
|
|
for (i = 0; i < req.ifm_count; i++) { |
701 |
|
|
if (IFM_TYPE(media_list[i]) == IFM_IEEE80211 |
702 |
|
|
&& IFM_SUBTYPE(media_list[i]) == IFM_AUTO) { |
703 |
|
|
/* OK, does it do monitor mode? */ |
704 |
|
|
if (media_list[i] & IFM_IEEE80211_MONITOR) { |
705 |
|
|
can_do = 1; |
706 |
|
|
break; |
707 |
|
|
} |
708 |
|
|
} |
709 |
|
|
} |
710 |
|
|
free(media_list); |
711 |
|
|
if (!can_do) { |
712 |
|
|
/* |
713 |
|
|
* This adapter doesn't support monitor mode. |
714 |
|
|
*/ |
715 |
|
|
close(sock); |
716 |
|
|
return (PCAP_ERROR_RFMON_NOTSUP); |
717 |
|
|
} |
718 |
|
|
|
719 |
|
|
if (set) { |
720 |
|
|
/* |
721 |
|
|
* Don't just check whether we can enable monitor mode, |
722 |
|
|
* do so, if it's not already enabled. |
723 |
|
|
*/ |
724 |
|
|
if ((req.ifm_current & IFM_IEEE80211_MONITOR) == 0) { |
725 |
|
|
/* |
726 |
|
|
* Monitor mode isn't currently on, so turn it on, |
727 |
|
|
* and remember that we should turn it off when the |
728 |
|
|
* pcap_t is closed. |
729 |
|
|
*/ |
730 |
|
|
|
731 |
|
|
/* |
732 |
|
|
* If we haven't already done so, arrange to have |
733 |
|
|
* "pcap_close_all()" called when we exit. |
734 |
|
|
*/ |
735 |
|
|
if (!pcap_do_addexit(p)) { |
736 |
|
|
/* |
737 |
|
|
* "atexit()" failed; don't put the interface |
738 |
|
|
* in monitor mode, just give up. |
739 |
|
|
*/ |
740 |
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
741 |
|
|
"atexit failed"); |
742 |
|
|
close(sock); |
743 |
|
|
return (PCAP_ERROR); |
744 |
|
|
} |
745 |
|
|
memset(&ifr, 0, sizeof(ifr)); |
746 |
|
|
(void)strlcpy(ifr.ifr_name, p->opt.source, |
747 |
|
|
sizeof(ifr.ifr_name)); |
748 |
|
|
ifr.ifr_media = req.ifm_current | IFM_IEEE80211_MONITOR; |
749 |
|
|
if (ioctl(sock, SIOCSIFMEDIA, &ifr) == -1) { |
750 |
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE, |
751 |
|
|
"SIOCSIFMEDIA: %s", pcap_strerror(errno)); |
752 |
|
|
close(sock); |
753 |
|
|
return (PCAP_ERROR); |
754 |
|
|
} |
755 |
|
|
|
756 |
|
|
p->md.must_do_on_close |= MUST_CLEAR_RFMON; |
757 |
|
|
|
758 |
|
|
/* |
759 |
|
|
* Add this to the list of pcaps to close when we exit. |
760 |
|
|
*/ |
761 |
|
|
pcap_add_to_pcaps_to_close(p); |
762 |
|
|
} |
763 |
|
|
} |
764 |
|
|
return (0); |
765 |
|
|
} |
766 |
|
|
|
767 |
|
|
/* |
768 |
|
|
* Check whether we have any 802.11 link-layer types; return the best |
769 |
|
|
* of the 802.11 link-layer types if we find one, and return -1 |
770 |
|
|
* otherwise. |
771 |
|
|
* |
772 |
|
|
* DLT_IEEE802_11_RADIO, with the radiotap header, is considered the |
773 |
|
|
* best 802.11 link-layer type; any of the other 802.11-plus-radio |
774 |
|
|
* headers are second-best; 802.11 with no radio information is |
775 |
|
|
* the least good. |
776 |
|
|
*/ |
777 |
|
|
static int |
778 |
|
|
find_802_11(struct bpf_dltlist *bdlp) |
779 |
|
|
{ |
780 |
|
|
int new_dlt; |
781 |
|
|
int i; |
782 |
|
|
|
783 |
|
|
/* |
784 |
|
|
* Scan the list of DLT_ values, looking for 802.11 values, |
785 |
|
|
* and, if we find any, choose the best of them. |
786 |
|
|
*/ |
787 |
|
|
new_dlt = -1; |
788 |
|
|
for (i = 0; i < bdlp->bfl_len; i++) { |
789 |
|
|
switch (bdlp->bfl_list[i]) { |
790 |
|
|
|
791 |
|
|
case DLT_IEEE802_11: |
792 |
|
|
/* |
793 |
|
|
* 802.11, but no radio. |
794 |
|
|
* |
795 |
|
|
* Offer this, and select it as the new mode |
796 |
|
|
* unless we've already found an 802.11 |
797 |
|
|
* header with radio information. |
798 |
|
|
*/ |
799 |
|
|
if (new_dlt == -1) |
800 |
|
|
new_dlt = bdlp->bfl_list[i]; |
801 |
|
|
break; |
802 |
|
|
|
803 |
|
|
case DLT_IEEE802_11_RADIO: |
804 |
|
|
/* |
805 |
|
|
* 802.11 with radiotap. |
806 |
|
|
* |
807 |
|
|
* Offer this, and select it as the new mode. |
808 |
|
|
*/ |
809 |
|
|
new_dlt = bdlp->bfl_list[i]; |
810 |
|
|
break; |
811 |
|
|
|
812 |
|
|
default: |
813 |
|
|
/* |
814 |
|
|
* Not 802.11. |
815 |
|
|
*/ |
816 |
|
|
break; |
817 |
|
|
} |
818 |
|
|
} |
819 |
|
|
|
820 |
|
|
return (new_dlt); |
821 |
|
|
} |
822 |
|
|
|
823 |
|
|
pcap_t * |
824 |
|
|
pcap_create(const char *device, char *errbuf) |
825 |
|
|
{ |
826 |
|
|
pcap_t *p; |
827 |
|
|
|
828 |
|
18 |
p = calloc(1, sizeof(*p)); |
829 |
✗✓ |
9 |
if (p == NULL) { |
830 |
|
|
snprintf(errbuf, PCAP_ERRBUF_SIZE, "malloc: %s", |
831 |
|
|
pcap_strerror(errno)); |
832 |
|
|
return (NULL); |
833 |
|
|
} |
834 |
|
9 |
p->fd = -1; /* not opened yet */ |
835 |
|
|
|
836 |
|
9 |
p->opt.source = strdup(device); |
837 |
✗✓ |
9 |
if (p->opt.source == NULL) { |
838 |
|
|
snprintf(errbuf, PCAP_ERRBUF_SIZE, "malloc: %s", |
839 |
|
|
pcap_strerror(errno)); |
840 |
|
|
free(p); |
841 |
|
|
return (NULL); |
842 |
|
|
} |
843 |
|
|
|
844 |
|
|
/* put in some defaults*/ |
845 |
|
9 |
pcap_set_timeout(p, 0); |
846 |
|
9 |
pcap_set_snaplen(p, 65535); /* max packet size */ |
847 |
|
9 |
p->opt.promisc = 0; |
848 |
|
9 |
p->opt.buffer_size = 0; |
849 |
|
9 |
return (p); |
850 |
|
9 |
} |
851 |
|
|
|
852 |
|
|
pcap_t * |
853 |
|
|
pcap_open_live(const char *source, int snaplen, int promisc, int to_ms, |
854 |
|
|
char *errbuf) |
855 |
|
|
{ |
856 |
|
|
pcap_t *p; |
857 |
|
|
int status; |
858 |
|
|
|
859 |
|
18 |
p = pcap_create(source, errbuf); |
860 |
✗✓ |
9 |
if (p == NULL) |
861 |
|
|
return (NULL); |
862 |
|
9 |
status = pcap_set_snaplen(p, snaplen); |
863 |
✓✗ |
9 |
if (status < 0) |
864 |
|
|
goto fail; |
865 |
|
9 |
status = pcap_set_promisc(p, promisc); |
866 |
✓✗ |
9 |
if (status < 0) |
867 |
|
|
goto fail; |
868 |
|
9 |
status = pcap_set_timeout(p, to_ms); |
869 |
✓✗ |
9 |
if (status < 0) |
870 |
|
|
goto fail; |
871 |
|
|
/* |
872 |
|
|
* Mark this as opened with pcap_open_live(), so that, for |
873 |
|
|
* example, we show the full list of DLT_ values, rather |
874 |
|
|
* than just the ones that are compatible with capturing |
875 |
|
|
* when not in monitor mode. That allows existing applications |
876 |
|
|
* to work the way they used to work, but allows new applications |
877 |
|
|
* that know about the new open API to, for example, find out the |
878 |
|
|
* DLT_ values that they can select without changing whether |
879 |
|
|
* the adapter is in monitor mode or not. |
880 |
|
|
*/ |
881 |
|
9 |
p->oldstyle = 1; |
882 |
|
9 |
status = pcap_activate(p); |
883 |
✓✗ |
9 |
if (status < 0) |
884 |
|
|
goto fail; |
885 |
|
9 |
return (p); |
886 |
|
|
fail: |
887 |
|
|
if (status == PCAP_ERROR) |
888 |
|
|
snprintf(errbuf, PCAP_ERRBUF_SIZE, "%s: %s", source, |
889 |
|
|
p->errbuf); |
890 |
|
|
else if (status == PCAP_ERROR_NO_SUCH_DEVICE || |
891 |
|
|
status == PCAP_ERROR_PERM_DENIED || |
892 |
|
|
status == PCAP_ERROR_PROMISC_PERM_DENIED) |
893 |
|
|
snprintf(errbuf, PCAP_ERRBUF_SIZE, "%s: %s (%s)", source, |
894 |
|
|
pcap_statustostr(status), p->errbuf); |
895 |
|
|
else |
896 |
|
|
snprintf(errbuf, PCAP_ERRBUF_SIZE, "%s: %s", source, |
897 |
|
|
pcap_statustostr(status)); |
898 |
|
|
pcap_close(p); |
899 |
|
|
return (NULL); |
900 |
|
9 |
} |
901 |
|
|
|
902 |
|
|
int |
903 |
|
|
pcap_setfilter(pcap_t *p, struct bpf_program *fp) |
904 |
|
|
{ |
905 |
|
|
/* |
906 |
|
|
* It looks that BPF code generated by gen_protochain() is not |
907 |
|
|
* compatible with some of kernel BPF code (for example BSD/OS 3.1). |
908 |
|
|
* Take a safer side for now. |
909 |
|
|
*/ |
910 |
✓✗✗✓
|
9 |
if (no_optimize || (p->sf.rfile != NULL)){ |
911 |
|
|
if (p->fcode.bf_insns != NULL) |
912 |
|
|
pcap_freecode(&p->fcode); |
913 |
|
|
p->fcode.bf_len = fp->bf_len; |
914 |
|
|
p->fcode.bf_insns = reallocarray(NULL, |
915 |
|
|
fp->bf_len, sizeof(*fp->bf_insns)); |
916 |
|
|
if (p->fcode.bf_insns == NULL) { |
917 |
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "malloc: %s", |
918 |
|
|
pcap_strerror(errno)); |
919 |
|
|
return (-1); |
920 |
|
|
} |
921 |
|
|
memcpy(p->fcode.bf_insns, fp->bf_insns, |
922 |
|
|
fp->bf_len * sizeof(*fp->bf_insns)); |
923 |
✗✓ |
3 |
} else if (ioctl(p->fd, BIOCSETF, (caddr_t)fp) < 0) { |
924 |
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCSETF: %s", |
925 |
|
|
pcap_strerror(errno)); |
926 |
|
|
return (-1); |
927 |
|
|
} |
928 |
|
3 |
return (0); |
929 |
|
3 |
} |
930 |
|
|
|
931 |
|
|
int |
932 |
|
|
pcap_setdirection(pcap_t *p, pcap_direction_t d) |
933 |
|
|
{ |
934 |
|
|
u_int dirfilt; |
935 |
|
|
|
936 |
|
|
switch (d) { |
937 |
|
|
case PCAP_D_INOUT: |
938 |
|
|
dirfilt = 0; |
939 |
|
|
break; |
940 |
|
|
case PCAP_D_IN: |
941 |
|
|
dirfilt = BPF_DIRECTION_OUT; |
942 |
|
|
break; |
943 |
|
|
case PCAP_D_OUT: |
944 |
|
|
dirfilt = BPF_DIRECTION_IN; |
945 |
|
|
break; |
946 |
|
|
default: |
947 |
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "Invalid direction"); |
948 |
|
|
return (-1); |
949 |
|
|
} |
950 |
|
|
if (ioctl(p->fd, BIOCSDIRFILT, &dirfilt) < 0) { |
951 |
|
|
snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "BIOCSDIRFILT: %s", |
952 |
|
|
pcap_strerror(errno)); |
953 |
|
|
return (-1); |
954 |
|
|
} |
955 |
|
|
return (0); |
956 |
|
|
} |
957 |
|
|
|
958 |
|
|
int |
959 |
|
|
pcap_set_datalink(pcap_t *p, int dlt) |
960 |
|
|
{ |
961 |
|
|
int i; |
962 |
|
|
|
963 |
|
|
if (p->dlt_count == 0) { |
964 |
|
|
/* |
965 |
|
|
* We couldn't fetch the list of DLTs, or we don't |
966 |
|
|
* have a "set datalink" operation, which means |
967 |
|
|
* this platform doesn't support changing the |
968 |
|
|
* DLT for an interface. Check whether the new |
969 |
|
|
* DLT is the one this interface supports. |
970 |
|
|
*/ |
971 |
|
|
if (p->linktype != dlt) |
972 |
|
|
goto unsupported; |
973 |
|
|
|
974 |
|
|
/* |
975 |
|
|
* It is, so there's nothing we need to do here. |
976 |
|
|
*/ |
977 |
|
|
return (0); |
978 |
|
|
} |
979 |
|
|
for (i = 0; i < p->dlt_count; i++) |
980 |
|
|
if (p->dlt_list[i] == dlt) |
981 |
|
|
break; |
982 |
|
|
if (i >= p->dlt_count) |
983 |
|
|
goto unsupported; |
984 |
|
|
if (ioctl(p->fd, BIOCSDLT, &dlt) == -1) { |
985 |
|
|
(void) snprintf(p->errbuf, sizeof(p->errbuf), |
986 |
|
|
"Cannot set DLT %d: %s", dlt, strerror(errno)); |
987 |
|
|
return (-1); |
988 |
|
|
} |
989 |
|
|
p->linktype = dlt; |
990 |
|
|
return (0); |
991 |
|
|
|
992 |
|
|
unsupported: |
993 |
|
|
(void) snprintf(p->errbuf, sizeof(p->errbuf), |
994 |
|
|
"DLT %d is not one of the DLTs supported by this device", |
995 |
|
|
dlt); |
996 |
|
|
return (-1); |
997 |
|
|
} |
998 |
|
|
|