xref: /freebsd/contrib/libpcap/pcap.c (revision 641a6cfb86023499caafe26a4d821a0b885cf00b)
1 /*
2  * Copyright (c) 1993, 1994, 1995, 1996, 1997, 1998
3  *	The Regents of the University of California.  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  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the Computer Systems
16  *	Engineering Group at Lawrence Berkeley Laboratory.
17  * 4. Neither the name of the University nor of the Laboratory may be used
18  *    to endorse or promote products derived from this software without
19  *    specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 static const char rcsid[] _U_ =
36     "@(#) $Header: /tcpdump/master/libpcap/pcap.c,v 1.128 2008-12-23 20:13:29 guy Exp $ (LBL)";
37 #endif
38 
39 #ifdef HAVE_CONFIG_H
40 #include "config.h"
41 #endif
42 
43 #ifdef WIN32
44 #include <pcap-stdinc.h>
45 #else /* WIN32 */
46 #if HAVE_INTTYPES_H
47 #include <inttypes.h>
48 #elif HAVE_STDINT_H
49 #include <stdint.h>
50 #endif
51 #ifdef HAVE_SYS_BITYPES_H
52 #include <sys/bitypes.h>
53 #endif
54 #include <sys/types.h>
55 #include <sys/mman.h>
56 #endif /* WIN32 */
57 
58 #include <stdio.h>
59 #include <stdlib.h>
60 #include <string.h>
61 #if !defined(_MSC_VER) && !defined(__BORLANDC__) && !defined(__MINGW32__)
62 #include <unistd.h>
63 #endif
64 #include <fcntl.h>
65 #include <errno.h>
66 
67 #ifdef HAVE_OS_PROTO_H
68 #include "os-proto.h"
69 #endif
70 
71 #ifdef MSDOS
72 #include "pcap-dos.h"
73 #endif
74 
75 #include "pcap-int.h"
76 
77 #ifdef HAVE_DAG_API
78 #include <dagnew.h>
79 #include <dagapi.h>
80 #endif
81 
82 int
83 pcap_not_initialized(pcap_t *pcap)
84 {
85 	/* this means 'not initialized' */
86 	return (PCAP_ERROR_NOT_ACTIVATED);
87 }
88 
89 /*
90  * Returns 1 if rfmon mode can be set on the pcap_t, 0 if it can't,
91  * a PCAP_ERROR value on an error.
92  */
93 int
94 pcap_can_set_rfmon(pcap_t *p)
95 {
96 	return (p->can_set_rfmon_op(p));
97 }
98 
99 /*
100  * For systems where rfmon mode is never supported.
101  */
102 static int
103 pcap_cant_set_rfmon(pcap_t *p _U_)
104 {
105 	return (0);
106 }
107 
108 /*
109  * Sets *tstamp_typesp to point to an array 1 or more supported time stamp
110  * types; the return value is the number of supported time stamp types.
111  * The list should be freed by a call to pcap_free_tstamp_types() when
112  * you're done with it.
113  *
114  * A return value of 0 means "you don't get a choice of time stamp type",
115  * in which case *tstamp_typesp is set to null.
116  *
117  * PCAP_ERROR is returned on error.
118  */
119 int
120 pcap_list_tstamp_types(pcap_t *p, int **tstamp_typesp)
121 {
122 	if (p->tstamp_type_count == 0) {
123 		/*
124 		 * We don't support multiple time stamp types.
125 		 */
126 		*tstamp_typesp = NULL;
127 	} else {
128 		*tstamp_typesp = (int*)calloc(sizeof(**tstamp_typesp),
129 		    p->tstamp_type_count);
130 		if (*tstamp_typesp == NULL) {
131 			(void)snprintf(p->errbuf, sizeof(p->errbuf),
132 			    "malloc: %s", pcap_strerror(errno));
133 			return (PCAP_ERROR);
134 		}
135 		(void)memcpy(*tstamp_typesp, p->tstamp_type_list,
136 		    sizeof(**tstamp_typesp) * p->tstamp_type_count);
137 	}
138 	return (p->tstamp_type_count);
139 }
140 
141 /*
142  * In Windows, you might have a library built with one version of the
143  * C runtime library and an application built with another version of
144  * the C runtime library, which means that the library might use one
145  * version of malloc() and free() and the application might use another
146  * version of malloc() and free().  If so, that means something
147  * allocated by the library cannot be freed by the application, so we
148  * need to have a pcap_free_tstamp_types() routine to free up the list
149  * allocated by pcap_list_tstamp_types(), even though it's just a wrapper
150  * around free().
151  */
152 void
153 pcap_free_tstamp_types(int *tstamp_type_list)
154 {
155 	free(tstamp_type_list);
156 }
157 
158 /*
159  * Default one-shot callback; overridden for capture types where the
160  * packet data cannot be guaranteed to be available after the callback
161  * returns, so that a copy must be made.
162  */
163 static void
164 pcap_oneshot(u_char *user, const struct pcap_pkthdr *h, const u_char *pkt)
165 {
166 	struct oneshot_userdata *sp = (struct oneshot_userdata *)user;
167 
168 	*sp->hdr = *h;
169 	*sp->pkt = pkt;
170 }
171 
172 const u_char *
173 pcap_next(pcap_t *p, struct pcap_pkthdr *h)
174 {
175 	struct oneshot_userdata s;
176 	const u_char *pkt;
177 
178 	s.hdr = h;
179 	s.pkt = &pkt;
180 	s.pd = p;
181 	if (pcap_dispatch(p, 1, p->oneshot_callback, (u_char *)&s) <= 0)
182 		return (0);
183 	return (pkt);
184 }
185 
186 int
187 pcap_next_ex(pcap_t *p, struct pcap_pkthdr **pkt_header,
188     const u_char **pkt_data)
189 {
190 	struct oneshot_userdata s;
191 
192 	s.hdr = &p->pcap_header;
193 	s.pkt = pkt_data;
194 	s.pd = p;
195 
196 	/* Saves a pointer to the packet headers */
197 	*pkt_header= &p->pcap_header;
198 
199 	if (p->sf.rfile != NULL) {
200 		int status;
201 
202 		/* We are on an offline capture */
203 		status = pcap_offline_read(p, 1, p->oneshot_callback,
204 		    (u_char *)&s);
205 
206 		/*
207 		 * Return codes for pcap_offline_read() are:
208 		 *   -  0: EOF
209 		 *   - -1: error
210 		 *   - >1: OK
211 		 * The first one ('0') conflicts with the return code of
212 		 * 0 from pcap_read() meaning "no packets arrived before
213 		 * the timeout expired", so we map it to -2 so you can
214 		 * distinguish between an EOF from a savefile and a
215 		 * "no packets arrived before the timeout expired, try
216 		 * again" from a live capture.
217 		 */
218 		if (status == 0)
219 			return (-2);
220 		else
221 			return (status);
222 	}
223 
224 	/*
225 	 * Return codes for pcap_read() are:
226 	 *   -  0: timeout
227 	 *   - -1: error
228 	 *   - -2: loop was broken out of with pcap_breakloop()
229 	 *   - >1: OK
230 	 * The first one ('0') conflicts with the return code of 0 from
231 	 * pcap_offline_read() meaning "end of file".
232 	*/
233 	return (p->read_op(p, 1, p->oneshot_callback, (u_char *)&s));
234 }
235 
236 static void
237 initialize_ops(pcap_t *p)
238 {
239 	/*
240 	 * Set operation pointers for operations that only work on
241 	 * an activated pcap_t to point to a routine that returns
242 	 * a "this isn't activated" error.
243 	 */
244 	p->read_op = (read_op_t)pcap_not_initialized;
245 	p->inject_op = (inject_op_t)pcap_not_initialized;
246 	p->setfilter_op = (setfilter_op_t)pcap_not_initialized;
247 	p->setdirection_op = (setdirection_op_t)pcap_not_initialized;
248 	p->set_datalink_op = (set_datalink_op_t)pcap_not_initialized;
249 	p->getnonblock_op = (getnonblock_op_t)pcap_not_initialized;
250 	p->setnonblock_op = (setnonblock_op_t)pcap_not_initialized;
251 	p->stats_op = (stats_op_t)pcap_not_initialized;
252 #ifdef WIN32
253 	p->setbuff_op = (setbuff_op_t)pcap_not_initialized;
254 	p->setmode_op = (setmode_op_t)pcap_not_initialized;
255 	p->setmintocopy_op = (setmintocopy_op_t)pcap_not_initialized;
256 #endif
257 
258 	/*
259 	 * Default cleanup operation - implementations can override
260 	 * this, but should call pcap_cleanup_live_common() after
261 	 * doing their own additional cleanup.
262 	 */
263 	p->cleanup_op = pcap_cleanup_live_common;
264 
265 	/*
266 	 * In most cases, the standard one-short callback can
267 	 * be used for pcap_next()/pcap_next_ex().
268 	 */
269 	p->oneshot_callback = pcap_oneshot;
270 }
271 
272 pcap_t *
273 pcap_create_common(const char *source, char *ebuf)
274 {
275 	pcap_t *p;
276 
277 	p = malloc(sizeof(*p));
278 	if (p == NULL) {
279 		snprintf(ebuf, PCAP_ERRBUF_SIZE, "malloc: %s",
280 		    pcap_strerror(errno));
281 		return (NULL);
282 	}
283 	memset(p, 0, sizeof(*p));
284 #ifndef WIN32
285 	p->fd = -1;	/* not opened yet */
286 	p->selectable_fd = -1;
287 	p->send_fd = -1;
288 #endif
289 
290 	p->opt.source = strdup(source);
291 	if (p->opt.source == NULL) {
292 		snprintf(ebuf, PCAP_ERRBUF_SIZE, "malloc: %s",
293 		    pcap_strerror(errno));
294 		free(p);
295 		return (NULL);
296 	}
297 
298 	/*
299 	 * Default to "can't set rfmon mode"; if it's supported by
300 	 * a platform, the create routine that called us can set
301 	 * the op to its routine to check whether a particular
302 	 * device supports it.
303 	 */
304 	p->can_set_rfmon_op = pcap_cant_set_rfmon;
305 
306 	initialize_ops(p);
307 
308 	/* put in some defaults*/
309 	pcap_set_timeout(p, 0);
310 	pcap_set_snaplen(p, 65535);	/* max packet size */
311 	p->opt.promisc = 0;
312 	p->opt.buffer_size = 0;
313 	p->opt.tstamp_type = -1;	/* default to not setting time stamp type */
314 	return (p);
315 }
316 
317 int
318 pcap_check_activated(pcap_t *p)
319 {
320 	if (p->activated) {
321 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "can't perform "
322 			" operation on activated capture");
323 		return (-1);
324 	}
325 	return (0);
326 }
327 
328 int
329 pcap_set_snaplen(pcap_t *p, int snaplen)
330 {
331 	if (pcap_check_activated(p))
332 		return (PCAP_ERROR_ACTIVATED);
333 	p->snapshot = snaplen;
334 	return (0);
335 }
336 
337 int
338 pcap_set_promisc(pcap_t *p, int promisc)
339 {
340 	if (pcap_check_activated(p))
341 		return (PCAP_ERROR_ACTIVATED);
342 	p->opt.promisc = promisc;
343 	return (0);
344 }
345 
346 int
347 pcap_set_rfmon(pcap_t *p, int rfmon)
348 {
349 	if (pcap_check_activated(p))
350 		return (PCAP_ERROR_ACTIVATED);
351 	p->opt.rfmon = rfmon;
352 	return (0);
353 }
354 
355 int
356 pcap_set_timeout(pcap_t *p, int timeout_ms)
357 {
358 	if (pcap_check_activated(p))
359 		return (PCAP_ERROR_ACTIVATED);
360 	p->md.timeout = timeout_ms;
361 	return (0);
362 }
363 
364 int
365 pcap_set_tstamp_type(pcap_t *p, int tstamp_type)
366 {
367 	int i;
368 
369 	if (pcap_check_activated(p))
370 		return (PCAP_ERROR_ACTIVATED);
371 
372 	/*
373 	 * If p->tstamp_type_count is 0, we don't support setting
374 	 * the time stamp type at all.
375 	 */
376 	if (p->tstamp_type_count == 0)
377 		return (PCAP_ERROR_CANTSET_TSTAMP_TYPE);
378 
379 	/*
380 	 * Check whether we claim to support this type of time stamp.
381 	 */
382 	for (i = 0; i < p->tstamp_type_count; i++) {
383 		if (p->tstamp_type_list[i] == tstamp_type) {
384 			/*
385 			 * Yes.
386 			 */
387 			p->opt.tstamp_type = tstamp_type;
388 			return (0);
389 		}
390 	}
391 
392 	/*
393 	 * No.  We support setting the time stamp type, but not to this
394 	 * particular value.
395 	 */
396 	return (PCAP_WARNING_TSTAMP_TYPE_NOTSUP);
397 }
398 
399 int
400 pcap_set_buffer_size(pcap_t *p, int buffer_size)
401 {
402 	if (pcap_check_activated(p))
403 		return (PCAP_ERROR_ACTIVATED);
404 	p->opt.buffer_size = buffer_size;
405 	return (0);
406 }
407 
408 int
409 pcap_activate(pcap_t *p)
410 {
411 	int status;
412 
413 	/*
414 	 * Catch attempts to re-activate an already-activated
415 	 * pcap_t; this should, for example, catch code that
416 	 * calls pcap_open_live() followed by pcap_activate(),
417 	 * as some code that showed up in a Stack Exchange
418 	 * question did.
419 	 */
420 	if (pcap_check_activated(p))
421 		return (PCAP_ERROR_ACTIVATED);
422 	status = p->activate_op(p);
423 	if (status >= 0)
424 		p->activated = 1;
425 	else {
426 		if (p->errbuf[0] == '\0') {
427 			/*
428 			 * No error message supplied by the activate routine;
429 			 * for the benefit of programs that don't specially
430 			 * handle errors other than PCAP_ERROR, return the
431 			 * error message corresponding to the status.
432 			 */
433 			snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "%s",
434 			    pcap_statustostr(status));
435 		}
436 
437 		/*
438 		 * Undo any operation pointer setting, etc. done by
439 		 * the activate operation.
440 		 */
441 		initialize_ops(p);
442 	}
443 	return (status);
444 }
445 
446 pcap_t *
447 pcap_open_live(const char *source, int snaplen, int promisc, int to_ms, char *errbuf)
448 {
449 	pcap_t *p;
450 	int status;
451 
452 	p = pcap_create(source, errbuf);
453 	if (p == NULL)
454 		return (NULL);
455 	status = pcap_set_snaplen(p, snaplen);
456 	if (status < 0)
457 		goto fail;
458 	status = pcap_set_promisc(p, promisc);
459 	if (status < 0)
460 		goto fail;
461 	status = pcap_set_timeout(p, to_ms);
462 	if (status < 0)
463 		goto fail;
464 	/*
465 	 * Mark this as opened with pcap_open_live(), so that, for
466 	 * example, we show the full list of DLT_ values, rather
467 	 * than just the ones that are compatible with capturing
468 	 * when not in monitor mode.  That allows existing applications
469 	 * to work the way they used to work, but allows new applications
470 	 * that know about the new open API to, for example, find out the
471 	 * DLT_ values that they can select without changing whether
472 	 * the adapter is in monitor mode or not.
473 	 */
474 	p->oldstyle = 1;
475 	status = pcap_activate(p);
476 	if (status < 0)
477 		goto fail;
478 	return (p);
479 fail:
480 	if (status == PCAP_ERROR)
481 		snprintf(errbuf, PCAP_ERRBUF_SIZE, "%s: %s", source,
482 		    p->errbuf);
483 	else if (status == PCAP_ERROR_NO_SUCH_DEVICE ||
484 	    status == PCAP_ERROR_PERM_DENIED ||
485 	    status == PCAP_ERROR_PROMISC_PERM_DENIED)
486 		snprintf(errbuf, PCAP_ERRBUF_SIZE, "%s: %s (%s)", source,
487 		    pcap_statustostr(status), p->errbuf);
488 	else
489 		snprintf(errbuf, PCAP_ERRBUF_SIZE, "%s: %s", source,
490 		    pcap_statustostr(status));
491 	pcap_close(p);
492 	return (NULL);
493 }
494 
495 int
496 pcap_dispatch(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
497 {
498 	return (p->read_op(p, cnt, callback, user));
499 }
500 
501 /*
502  * XXX - is this necessary?
503  */
504 int
505 pcap_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
506 {
507 
508 	return (p->read_op(p, cnt, callback, user));
509 }
510 
511 int
512 pcap_loop(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
513 {
514 	register int n;
515 
516 	for (;;) {
517 		if (p->sf.rfile != NULL) {
518 			/*
519 			 * 0 means EOF, so don't loop if we get 0.
520 			 */
521 			n = pcap_offline_read(p, cnt, callback, user);
522 		} else {
523 			/*
524 			 * XXX keep reading until we get something
525 			 * (or an error occurs)
526 			 */
527 			do {
528 				n = p->read_op(p, cnt, callback, user);
529 			} while (n == 0);
530 		}
531 		if (n <= 0)
532 			return (n);
533 		if (cnt > 0) {
534 			cnt -= n;
535 			if (cnt <= 0)
536 				return (0);
537 		}
538 	}
539 }
540 
541 /*
542  * Force the loop in "pcap_read()" or "pcap_read_offline()" to terminate.
543  */
544 void
545 pcap_breakloop(pcap_t *p)
546 {
547 	p->break_loop = 1;
548 }
549 
550 int
551 pcap_datalink(pcap_t *p)
552 {
553 	return (p->linktype);
554 }
555 
556 int
557 pcap_datalink_ext(pcap_t *p)
558 {
559 	return (p->linktype_ext);
560 }
561 
562 int
563 pcap_list_datalinks(pcap_t *p, int **dlt_buffer)
564 {
565 	if (p->dlt_count == 0) {
566 		/*
567 		 * We couldn't fetch the list of DLTs, which means
568 		 * this platform doesn't support changing the
569 		 * DLT for an interface.  Return a list of DLTs
570 		 * containing only the DLT this device supports.
571 		 */
572 		*dlt_buffer = (int*)malloc(sizeof(**dlt_buffer));
573 		if (*dlt_buffer == NULL) {
574 			(void)snprintf(p->errbuf, sizeof(p->errbuf),
575 			    "malloc: %s", pcap_strerror(errno));
576 			return (-1);
577 		}
578 		**dlt_buffer = p->linktype;
579 		return (1);
580 	} else {
581 		*dlt_buffer = (int*)calloc(sizeof(**dlt_buffer), p->dlt_count);
582 		if (*dlt_buffer == NULL) {
583 			(void)snprintf(p->errbuf, sizeof(p->errbuf),
584 			    "malloc: %s", pcap_strerror(errno));
585 			return (-1);
586 		}
587 		(void)memcpy(*dlt_buffer, p->dlt_list,
588 		    sizeof(**dlt_buffer) * p->dlt_count);
589 		return (p->dlt_count);
590 	}
591 }
592 
593 /*
594  * In Windows, you might have a library built with one version of the
595  * C runtime library and an application built with another version of
596  * the C runtime library, which means that the library might use one
597  * version of malloc() and free() and the application might use another
598  * version of malloc() and free().  If so, that means something
599  * allocated by the library cannot be freed by the application, so we
600  * need to have a pcap_free_datalinks() routine to free up the list
601  * allocated by pcap_list_datalinks(), even though it's just a wrapper
602  * around free().
603  */
604 void
605 pcap_free_datalinks(int *dlt_list)
606 {
607 	free(dlt_list);
608 }
609 
610 int
611 pcap_set_datalink(pcap_t *p, int dlt)
612 {
613 	int i;
614 	const char *dlt_name;
615 
616 	if (p->dlt_count == 0 || p->set_datalink_op == NULL) {
617 		/*
618 		 * We couldn't fetch the list of DLTs, or we don't
619 		 * have a "set datalink" operation, which means
620 		 * this platform doesn't support changing the
621 		 * DLT for an interface.  Check whether the new
622 		 * DLT is the one this interface supports.
623 		 */
624 		if (p->linktype != dlt)
625 			goto unsupported;
626 
627 		/*
628 		 * It is, so there's nothing we need to do here.
629 		 */
630 		return (0);
631 	}
632 	for (i = 0; i < p->dlt_count; i++)
633 		if (p->dlt_list[i] == dlt)
634 			break;
635 	if (i >= p->dlt_count)
636 		goto unsupported;
637 	if (p->dlt_count == 2 && p->dlt_list[0] == DLT_EN10MB &&
638 	    dlt == DLT_DOCSIS) {
639 		/*
640 		 * This is presumably an Ethernet device, as the first
641 		 * link-layer type it offers is DLT_EN10MB, and the only
642 		 * other type it offers is DLT_DOCSIS.  That means that
643 		 * we can't tell the driver to supply DOCSIS link-layer
644 		 * headers - we're just pretending that's what we're
645 		 * getting, as, presumably, we're capturing on a dedicated
646 		 * link to a Cisco Cable Modem Termination System, and
647 		 * it's putting raw DOCSIS frames on the wire inside low-level
648 		 * Ethernet framing.
649 		 */
650 		p->linktype = dlt;
651 		return (0);
652 	}
653 	if (p->set_datalink_op(p, dlt) == -1)
654 		return (-1);
655 	p->linktype = dlt;
656 	return (0);
657 
658 unsupported:
659 	dlt_name = pcap_datalink_val_to_name(dlt);
660 	if (dlt_name != NULL) {
661 		(void) snprintf(p->errbuf, sizeof(p->errbuf),
662 		    "%s is not one of the DLTs supported by this device",
663 		    dlt_name);
664 	} else {
665 		(void) snprintf(p->errbuf, sizeof(p->errbuf),
666 		    "DLT %d is not one of the DLTs supported by this device",
667 		    dlt);
668 	}
669 	return (-1);
670 }
671 
672 /*
673  * This array is designed for mapping upper and lower case letter
674  * together for a case independent comparison.  The mappings are
675  * based upon ascii character sequences.
676  */
677 static const u_char charmap[] = {
678 	(u_char)'\000', (u_char)'\001', (u_char)'\002', (u_char)'\003',
679 	(u_char)'\004', (u_char)'\005', (u_char)'\006', (u_char)'\007',
680 	(u_char)'\010', (u_char)'\011', (u_char)'\012', (u_char)'\013',
681 	(u_char)'\014', (u_char)'\015', (u_char)'\016', (u_char)'\017',
682 	(u_char)'\020', (u_char)'\021', (u_char)'\022', (u_char)'\023',
683 	(u_char)'\024', (u_char)'\025', (u_char)'\026', (u_char)'\027',
684 	(u_char)'\030', (u_char)'\031', (u_char)'\032', (u_char)'\033',
685 	(u_char)'\034', (u_char)'\035', (u_char)'\036', (u_char)'\037',
686 	(u_char)'\040', (u_char)'\041', (u_char)'\042', (u_char)'\043',
687 	(u_char)'\044', (u_char)'\045', (u_char)'\046', (u_char)'\047',
688 	(u_char)'\050', (u_char)'\051', (u_char)'\052', (u_char)'\053',
689 	(u_char)'\054', (u_char)'\055', (u_char)'\056', (u_char)'\057',
690 	(u_char)'\060', (u_char)'\061', (u_char)'\062', (u_char)'\063',
691 	(u_char)'\064', (u_char)'\065', (u_char)'\066', (u_char)'\067',
692 	(u_char)'\070', (u_char)'\071', (u_char)'\072', (u_char)'\073',
693 	(u_char)'\074', (u_char)'\075', (u_char)'\076', (u_char)'\077',
694 	(u_char)'\100', (u_char)'\141', (u_char)'\142', (u_char)'\143',
695 	(u_char)'\144', (u_char)'\145', (u_char)'\146', (u_char)'\147',
696 	(u_char)'\150', (u_char)'\151', (u_char)'\152', (u_char)'\153',
697 	(u_char)'\154', (u_char)'\155', (u_char)'\156', (u_char)'\157',
698 	(u_char)'\160', (u_char)'\161', (u_char)'\162', (u_char)'\163',
699 	(u_char)'\164', (u_char)'\165', (u_char)'\166', (u_char)'\167',
700 	(u_char)'\170', (u_char)'\171', (u_char)'\172', (u_char)'\133',
701 	(u_char)'\134', (u_char)'\135', (u_char)'\136', (u_char)'\137',
702 	(u_char)'\140', (u_char)'\141', (u_char)'\142', (u_char)'\143',
703 	(u_char)'\144', (u_char)'\145', (u_char)'\146', (u_char)'\147',
704 	(u_char)'\150', (u_char)'\151', (u_char)'\152', (u_char)'\153',
705 	(u_char)'\154', (u_char)'\155', (u_char)'\156', (u_char)'\157',
706 	(u_char)'\160', (u_char)'\161', (u_char)'\162', (u_char)'\163',
707 	(u_char)'\164', (u_char)'\165', (u_char)'\166', (u_char)'\167',
708 	(u_char)'\170', (u_char)'\171', (u_char)'\172', (u_char)'\173',
709 	(u_char)'\174', (u_char)'\175', (u_char)'\176', (u_char)'\177',
710 	(u_char)'\200', (u_char)'\201', (u_char)'\202', (u_char)'\203',
711 	(u_char)'\204', (u_char)'\205', (u_char)'\206', (u_char)'\207',
712 	(u_char)'\210', (u_char)'\211', (u_char)'\212', (u_char)'\213',
713 	(u_char)'\214', (u_char)'\215', (u_char)'\216', (u_char)'\217',
714 	(u_char)'\220', (u_char)'\221', (u_char)'\222', (u_char)'\223',
715 	(u_char)'\224', (u_char)'\225', (u_char)'\226', (u_char)'\227',
716 	(u_char)'\230', (u_char)'\231', (u_char)'\232', (u_char)'\233',
717 	(u_char)'\234', (u_char)'\235', (u_char)'\236', (u_char)'\237',
718 	(u_char)'\240', (u_char)'\241', (u_char)'\242', (u_char)'\243',
719 	(u_char)'\244', (u_char)'\245', (u_char)'\246', (u_char)'\247',
720 	(u_char)'\250', (u_char)'\251', (u_char)'\252', (u_char)'\253',
721 	(u_char)'\254', (u_char)'\255', (u_char)'\256', (u_char)'\257',
722 	(u_char)'\260', (u_char)'\261', (u_char)'\262', (u_char)'\263',
723 	(u_char)'\264', (u_char)'\265', (u_char)'\266', (u_char)'\267',
724 	(u_char)'\270', (u_char)'\271', (u_char)'\272', (u_char)'\273',
725 	(u_char)'\274', (u_char)'\275', (u_char)'\276', (u_char)'\277',
726 	(u_char)'\300', (u_char)'\341', (u_char)'\342', (u_char)'\343',
727 	(u_char)'\344', (u_char)'\345', (u_char)'\346', (u_char)'\347',
728 	(u_char)'\350', (u_char)'\351', (u_char)'\352', (u_char)'\353',
729 	(u_char)'\354', (u_char)'\355', (u_char)'\356', (u_char)'\357',
730 	(u_char)'\360', (u_char)'\361', (u_char)'\362', (u_char)'\363',
731 	(u_char)'\364', (u_char)'\365', (u_char)'\366', (u_char)'\367',
732 	(u_char)'\370', (u_char)'\371', (u_char)'\372', (u_char)'\333',
733 	(u_char)'\334', (u_char)'\335', (u_char)'\336', (u_char)'\337',
734 	(u_char)'\340', (u_char)'\341', (u_char)'\342', (u_char)'\343',
735 	(u_char)'\344', (u_char)'\345', (u_char)'\346', (u_char)'\347',
736 	(u_char)'\350', (u_char)'\351', (u_char)'\352', (u_char)'\353',
737 	(u_char)'\354', (u_char)'\355', (u_char)'\356', (u_char)'\357',
738 	(u_char)'\360', (u_char)'\361', (u_char)'\362', (u_char)'\363',
739 	(u_char)'\364', (u_char)'\365', (u_char)'\366', (u_char)'\367',
740 	(u_char)'\370', (u_char)'\371', (u_char)'\372', (u_char)'\373',
741 	(u_char)'\374', (u_char)'\375', (u_char)'\376', (u_char)'\377',
742 };
743 
744 int
745 pcap_strcasecmp(const char *s1, const char *s2)
746 {
747 	register const u_char	*cm = charmap,
748 				*us1 = (const u_char *)s1,
749 				*us2 = (const u_char *)s2;
750 
751 	while (cm[*us1] == cm[*us2++])
752 		if (*us1++ == '\0')
753 			return(0);
754 	return (cm[*us1] - cm[*--us2]);
755 }
756 
757 struct dlt_choice {
758 	const char *name;
759 	const char *description;
760 	int	dlt;
761 };
762 
763 #define DLT_CHOICE(code, description) { #code, description, code }
764 #define DLT_CHOICE_SENTINEL { NULL, NULL, 0 }
765 
766 static struct dlt_choice dlt_choices[] = {
767 	DLT_CHOICE(DLT_NULL, "BSD loopback"),
768 	DLT_CHOICE(DLT_EN10MB, "Ethernet"),
769 	DLT_CHOICE(DLT_IEEE802, "Token ring"),
770 	DLT_CHOICE(DLT_ARCNET, "BSD ARCNET"),
771 	DLT_CHOICE(DLT_SLIP, "SLIP"),
772 	DLT_CHOICE(DLT_PPP, "PPP"),
773 	DLT_CHOICE(DLT_FDDI, "FDDI"),
774 	DLT_CHOICE(DLT_ATM_RFC1483, "RFC 1483 LLC-encapsulated ATM"),
775 	DLT_CHOICE(DLT_RAW, "Raw IP"),
776 	DLT_CHOICE(DLT_SLIP_BSDOS, "BSD/OS SLIP"),
777 	DLT_CHOICE(DLT_PPP_BSDOS, "BSD/OS PPP"),
778 	DLT_CHOICE(DLT_ATM_CLIP, "Linux Classical IP-over-ATM"),
779 	DLT_CHOICE(DLT_PPP_SERIAL, "PPP over serial"),
780 	DLT_CHOICE(DLT_PPP_ETHER, "PPPoE"),
781         DLT_CHOICE(DLT_SYMANTEC_FIREWALL, "Symantec Firewall"),
782 	DLT_CHOICE(DLT_C_HDLC, "Cisco HDLC"),
783 	DLT_CHOICE(DLT_IEEE802_11, "802.11"),
784 	DLT_CHOICE(DLT_FRELAY, "Frame Relay"),
785 	DLT_CHOICE(DLT_LOOP, "OpenBSD loopback"),
786 	DLT_CHOICE(DLT_ENC, "OpenBSD encapsulated IP"),
787 	DLT_CHOICE(DLT_LINUX_SLL, "Linux cooked"),
788 	DLT_CHOICE(DLT_LTALK, "Localtalk"),
789 	DLT_CHOICE(DLT_PFLOG, "OpenBSD pflog file"),
790 	DLT_CHOICE(DLT_PRISM_HEADER, "802.11 plus Prism header"),
791 	DLT_CHOICE(DLT_IP_OVER_FC, "RFC 2625 IP-over-Fibre Channel"),
792 	DLT_CHOICE(DLT_SUNATM, "Sun raw ATM"),
793 	DLT_CHOICE(DLT_IEEE802_11_RADIO, "802.11 plus radiotap header"),
794 	DLT_CHOICE(DLT_ARCNET_LINUX, "Linux ARCNET"),
795         DLT_CHOICE(DLT_JUNIPER_MLPPP, "Juniper Multi-Link PPP"),
796 	DLT_CHOICE(DLT_JUNIPER_MLFR, "Juniper Multi-Link Frame Relay"),
797         DLT_CHOICE(DLT_JUNIPER_ES, "Juniper Encryption Services PIC"),
798         DLT_CHOICE(DLT_JUNIPER_GGSN, "Juniper GGSN PIC"),
799 	DLT_CHOICE(DLT_JUNIPER_MFR, "Juniper FRF.16 Frame Relay"),
800         DLT_CHOICE(DLT_JUNIPER_ATM2, "Juniper ATM2 PIC"),
801         DLT_CHOICE(DLT_JUNIPER_SERVICES, "Juniper Advanced Services PIC"),
802         DLT_CHOICE(DLT_JUNIPER_ATM1, "Juniper ATM1 PIC"),
803 	DLT_CHOICE(DLT_APPLE_IP_OVER_IEEE1394, "Apple IP-over-IEEE 1394"),
804 	DLT_CHOICE(DLT_MTP2_WITH_PHDR, "SS7 MTP2 with Pseudo-header"),
805 	DLT_CHOICE(DLT_MTP2, "SS7 MTP2"),
806 	DLT_CHOICE(DLT_MTP3, "SS7 MTP3"),
807 	DLT_CHOICE(DLT_SCCP, "SS7 SCCP"),
808 	DLT_CHOICE(DLT_DOCSIS, "DOCSIS"),
809 	DLT_CHOICE(DLT_LINUX_IRDA, "Linux IrDA"),
810 	DLT_CHOICE(DLT_IEEE802_11_RADIO_AVS, "802.11 plus AVS radio information header"),
811         DLT_CHOICE(DLT_JUNIPER_MONITOR, "Juniper Passive Monitor PIC"),
812 	DLT_CHOICE(DLT_PPP_PPPD, "PPP for pppd, with direction flag"),
813 	DLT_CHOICE(DLT_JUNIPER_PPPOE, "Juniper PPPoE"),
814 	DLT_CHOICE(DLT_JUNIPER_PPPOE_ATM, "Juniper PPPoE/ATM"),
815 	DLT_CHOICE(DLT_GPRS_LLC, "GPRS LLC"),
816 	DLT_CHOICE(DLT_GPF_T, "GPF-T"),
817 	DLT_CHOICE(DLT_GPF_F, "GPF-F"),
818 	DLT_CHOICE(DLT_JUNIPER_PIC_PEER, "Juniper PIC Peer"),
819 	DLT_CHOICE(DLT_ERF_ETH,	"Ethernet with Endace ERF header"),
820 	DLT_CHOICE(DLT_ERF_POS, "Packet-over-SONET with Endace ERF header"),
821 	DLT_CHOICE(DLT_LINUX_LAPD, "Linux vISDN LAPD"),
822 	DLT_CHOICE(DLT_JUNIPER_ETHER, "Juniper Ethernet"),
823 	DLT_CHOICE(DLT_JUNIPER_PPP, "Juniper PPP"),
824 	DLT_CHOICE(DLT_JUNIPER_FRELAY, "Juniper Frame Relay"),
825 	DLT_CHOICE(DLT_JUNIPER_CHDLC, "Juniper C-HDLC"),
826 	DLT_CHOICE(DLT_MFR, "FRF.16 Frame Relay"),
827 	DLT_CHOICE(DLT_JUNIPER_VP, "Juniper Voice PIC"),
828 	DLT_CHOICE(DLT_A429, "Arinc 429"),
829 	DLT_CHOICE(DLT_A653_ICM, "Arinc 653 Interpartition Communication"),
830 	DLT_CHOICE(DLT_USB, "USB"),
831 	DLT_CHOICE(DLT_BLUETOOTH_HCI_H4, "Bluetooth HCI UART transport layer"),
832 	DLT_CHOICE(DLT_IEEE802_16_MAC_CPS, "IEEE 802.16 MAC Common Part Sublayer"),
833 	DLT_CHOICE(DLT_USB_LINUX, "USB with Linux header"),
834 	DLT_CHOICE(DLT_CAN20B, "Controller Area Network (CAN) v. 2.0B"),
835 	DLT_CHOICE(DLT_IEEE802_15_4_LINUX, "IEEE 802.15.4 with Linux padding"),
836 	DLT_CHOICE(DLT_PPI, "Per-Packet Information"),
837 	DLT_CHOICE(DLT_IEEE802_16_MAC_CPS_RADIO, "IEEE 802.16 MAC Common Part Sublayer plus radiotap header"),
838 	DLT_CHOICE(DLT_JUNIPER_ISM, "Juniper Integrated Service Module"),
839 	DLT_CHOICE(DLT_IEEE802_15_4, "IEEE 802.15.4 with FCS"),
840 	DLT_CHOICE(DLT_SITA, "SITA pseudo-header"),
841 	DLT_CHOICE(DLT_ERF, "Endace ERF header"),
842 	DLT_CHOICE(DLT_RAIF1, "Ethernet with u10 Networks pseudo-header"),
843 	DLT_CHOICE(DLT_IPMB, "IPMB"),
844 	DLT_CHOICE(DLT_JUNIPER_ST, "Juniper Secure Tunnel"),
845 	DLT_CHOICE(DLT_BLUETOOTH_HCI_H4_WITH_PHDR, "Bluetooth HCI UART transport layer plus pseudo-header"),
846 	DLT_CHOICE(DLT_AX25_KISS, "AX.25 with KISS header"),
847 	DLT_CHOICE(DLT_IEEE802_15_4_NONASK_PHY, "IEEE 802.15.4 with non-ASK PHY data"),
848 	DLT_CHOICE(DLT_MPLS, "MPLS with label as link-layer header"),
849 	DLT_CHOICE(DLT_USB_LINUX_MMAPPED, "USB with padded Linux header"),
850 	DLT_CHOICE(DLT_DECT, "DECT"),
851 	DLT_CHOICE(DLT_AOS, "AOS Space Data Link protocol"),
852 	DLT_CHOICE(DLT_WIHART, "Wireless HART"),
853 	DLT_CHOICE(DLT_FC_2, "Fibre Channel FC-2"),
854 	DLT_CHOICE(DLT_FC_2_WITH_FRAME_DELIMS, "Fibre Channel FC-2 with frame delimiters"),
855 	DLT_CHOICE(DLT_IPNET, "Solaris ipnet"),
856 	DLT_CHOICE(DLT_CAN_SOCKETCAN, "CAN-bus with SocketCAN headers"),
857 	DLT_CHOICE(DLT_IPV4, "Raw IPv4"),
858 	DLT_CHOICE(DLT_IPV6, "Raw IPv6"),
859 	DLT_CHOICE(DLT_IEEE802_15_4_NOFCS, "IEEE 802.15.4 without FCS"),
860 	DLT_CHOICE(DLT_JUNIPER_VS, "Juniper Virtual Server"),
861 	DLT_CHOICE(DLT_JUNIPER_SRX_E2E, "Juniper SRX E2E"),
862 	DLT_CHOICE(DLT_JUNIPER_FIBRECHANNEL, "Juniper Fibre Channel"),
863 	DLT_CHOICE(DLT_DVB_CI, "DVB-CI"),
864 	DLT_CHOICE(DLT_JUNIPER_ATM_CEMIC, "Juniper ATM CEMIC"),
865 	DLT_CHOICE(DLT_NFLOG, "Linux netfilter log messages"),
866 	DLT_CHOICE(DLT_NETANALYZER, "Ethernet with Hilscher netANALYZER pseudo-header"),
867 	DLT_CHOICE(DLT_NETANALYZER_TRANSPARENT, "Ethernet with Hilscher netANALYZER pseudo-header and with preamble and SFD"),
868 	DLT_CHOICE(DLT_IPOIB, "RFC 4391 IP-over-Infiniband"),
869 	DLT_CHOICE_SENTINEL
870 };
871 
872 int
873 pcap_datalink_name_to_val(const char *name)
874 {
875 	int i;
876 
877 	for (i = 0; dlt_choices[i].name != NULL; i++) {
878 		if (pcap_strcasecmp(dlt_choices[i].name + sizeof("DLT_") - 1,
879 		    name) == 0)
880 			return (dlt_choices[i].dlt);
881 	}
882 	return (-1);
883 }
884 
885 const char *
886 pcap_datalink_val_to_name(int dlt)
887 {
888 	int i;
889 
890 	for (i = 0; dlt_choices[i].name != NULL; i++) {
891 		if (dlt_choices[i].dlt == dlt)
892 			return (dlt_choices[i].name + sizeof("DLT_") - 1);
893 	}
894 	return (NULL);
895 }
896 
897 const char *
898 pcap_datalink_val_to_description(int dlt)
899 {
900 	int i;
901 
902 	for (i = 0; dlt_choices[i].name != NULL; i++) {
903 		if (dlt_choices[i].dlt == dlt)
904 			return (dlt_choices[i].description);
905 	}
906 	return (NULL);
907 }
908 
909 struct tstamp_type_choice {
910 	const char *name;
911 	const char *description;
912 	int	type;
913 };
914 
915 static struct tstamp_type_choice tstamp_type_choices[] = {
916 	{ "host", "Host", PCAP_TSTAMP_HOST },
917 	{ "host_lowprec", "Host, low precision", PCAP_TSTAMP_HOST_LOWPREC },
918 	{ "host_hiprec", "Host, high precision", PCAP_TSTAMP_HOST_HIPREC },
919 	{ "adapter", "Adapter", PCAP_TSTAMP_ADAPTER },
920 	{ "adapter_unsynced", "Adapter, not synced with system time", PCAP_TSTAMP_ADAPTER_UNSYNCED },
921 	{ NULL, NULL, 0 }
922 };
923 
924 int
925 pcap_tstamp_type_name_to_val(const char *name)
926 {
927 	int i;
928 
929 	for (i = 0; tstamp_type_choices[i].name != NULL; i++) {
930 		if (pcap_strcasecmp(tstamp_type_choices[i].name, name) == 0)
931 			return (tstamp_type_choices[i].type);
932 	}
933 	return (PCAP_ERROR);
934 }
935 
936 const char *
937 pcap_tstamp_type_val_to_name(int tstamp_type)
938 {
939 	int i;
940 
941 	for (i = 0; tstamp_type_choices[i].name != NULL; i++) {
942 		if (tstamp_type_choices[i].type == tstamp_type)
943 			return (tstamp_type_choices[i].name);
944 	}
945 	return (NULL);
946 }
947 
948 const char *
949 pcap_tstamp_type_val_to_description(int tstamp_type)
950 {
951 	int i;
952 
953 	for (i = 0; tstamp_type_choices[i].name != NULL; i++) {
954 		if (tstamp_type_choices[i].type == tstamp_type)
955 			return (tstamp_type_choices[i].description);
956 	}
957 	return (NULL);
958 }
959 
960 int
961 pcap_snapshot(pcap_t *p)
962 {
963 	return (p->snapshot);
964 }
965 
966 int
967 pcap_is_swapped(pcap_t *p)
968 {
969 	return (p->sf.swapped);
970 }
971 
972 int
973 pcap_major_version(pcap_t *p)
974 {
975 	return (p->sf.version_major);
976 }
977 
978 int
979 pcap_minor_version(pcap_t *p)
980 {
981 	return (p->sf.version_minor);
982 }
983 
984 FILE *
985 pcap_file(pcap_t *p)
986 {
987 	return (p->sf.rfile);
988 }
989 
990 int
991 pcap_fileno(pcap_t *p)
992 {
993 #ifndef WIN32
994 	return (p->fd);
995 #else
996 	if (p->adapter != NULL)
997 		return ((int)(DWORD)p->adapter->hFile);
998 	else
999 		return (-1);
1000 #endif
1001 }
1002 
1003 #if !defined(WIN32) && !defined(MSDOS)
1004 int
1005 pcap_get_selectable_fd(pcap_t *p)
1006 {
1007 	return (p->selectable_fd);
1008 }
1009 #endif
1010 
1011 void
1012 pcap_perror(pcap_t *p, char *prefix)
1013 {
1014 	fprintf(stderr, "%s: %s\n", prefix, p->errbuf);
1015 }
1016 
1017 char *
1018 pcap_geterr(pcap_t *p)
1019 {
1020 	return (p->errbuf);
1021 }
1022 
1023 int
1024 pcap_getnonblock(pcap_t *p, char *errbuf)
1025 {
1026 	return (p->getnonblock_op(p, errbuf));
1027 }
1028 
1029 /*
1030  * Get the current non-blocking mode setting, under the assumption that
1031  * it's just the standard POSIX non-blocking flag.
1032  *
1033  * We don't look at "p->nonblock", in case somebody tweaked the FD
1034  * directly.
1035  */
1036 #if !defined(WIN32) && !defined(MSDOS)
1037 int
1038 pcap_getnonblock_fd(pcap_t *p, char *errbuf)
1039 {
1040 	int fdflags;
1041 
1042 	fdflags = fcntl(p->fd, F_GETFL, 0);
1043 	if (fdflags == -1) {
1044 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "F_GETFL: %s",
1045 		    pcap_strerror(errno));
1046 		return (-1);
1047 	}
1048 	if (fdflags & O_NONBLOCK)
1049 		return (1);
1050 	else
1051 		return (0);
1052 }
1053 #endif
1054 
1055 int
1056 pcap_setnonblock(pcap_t *p, int nonblock, char *errbuf)
1057 {
1058 	return (p->setnonblock_op(p, nonblock, errbuf));
1059 }
1060 
1061 #if !defined(WIN32) && !defined(MSDOS)
1062 /*
1063  * Set non-blocking mode, under the assumption that it's just the
1064  * standard POSIX non-blocking flag.  (This can be called by the
1065  * per-platform non-blocking-mode routine if that routine also
1066  * needs to do some additional work.)
1067  */
1068 int
1069 pcap_setnonblock_fd(pcap_t *p, int nonblock, char *errbuf)
1070 {
1071 	int fdflags;
1072 
1073 	fdflags = fcntl(p->fd, F_GETFL, 0);
1074 	if (fdflags == -1) {
1075 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "F_GETFL: %s",
1076 		    pcap_strerror(errno));
1077 		return (-1);
1078 	}
1079 	if (nonblock)
1080 		fdflags |= O_NONBLOCK;
1081 	else
1082 		fdflags &= ~O_NONBLOCK;
1083 	if (fcntl(p->fd, F_SETFL, fdflags) == -1) {
1084 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "F_SETFL: %s",
1085 		    pcap_strerror(errno));
1086 		return (-1);
1087 	}
1088 	return (0);
1089 }
1090 #endif
1091 
1092 #ifdef WIN32
1093 /*
1094  * Generate a string for the last Win32-specific error (i.e. an error generated when
1095  * calling a Win32 API).
1096  * For errors occurred during standard C calls, we still use pcap_strerror()
1097  */
1098 char *
1099 pcap_win32strerror(void)
1100 {
1101 	DWORD error;
1102 	static char errbuf[PCAP_ERRBUF_SIZE+1];
1103 	int errlen;
1104 	char *p;
1105 
1106 	error = GetLastError();
1107 	FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, NULL, error, 0, errbuf,
1108 	    PCAP_ERRBUF_SIZE, NULL);
1109 
1110 	/*
1111 	 * "FormatMessage()" "helpfully" sticks CR/LF at the end of the
1112 	 * message.  Get rid of it.
1113 	 */
1114 	errlen = strlen(errbuf);
1115 	if (errlen >= 2) {
1116 		errbuf[errlen - 1] = '\0';
1117 		errbuf[errlen - 2] = '\0';
1118 	}
1119 	p = strchr(errbuf, '\0');
1120 	snprintf (p, sizeof(errbuf)-(p-errbuf), " (%lu)", error);
1121 	return (errbuf);
1122 }
1123 #endif
1124 
1125 /*
1126  * Generate error strings for PCAP_ERROR_ and PCAP_WARNING_ values.
1127  */
1128 const char *
1129 pcap_statustostr(int errnum)
1130 {
1131 	static char ebuf[15+10+1];
1132 
1133 	switch (errnum) {
1134 
1135 	case PCAP_WARNING:
1136 		return("Generic warning");
1137 
1138 	case PCAP_WARNING_TSTAMP_TYPE_NOTSUP:
1139 		return ("That type of time stamp is not supported by that device");
1140 
1141 	case PCAP_WARNING_PROMISC_NOTSUP:
1142 		return ("That device doesn't support promiscuous mode");
1143 
1144 	case PCAP_ERROR:
1145 		return("Generic error");
1146 
1147 	case PCAP_ERROR_BREAK:
1148 		return("Loop terminated by pcap_breakloop");
1149 
1150 	case PCAP_ERROR_NOT_ACTIVATED:
1151 		return("The pcap_t has not been activated");
1152 
1153 	case PCAP_ERROR_ACTIVATED:
1154 		return ("The setting can't be changed after the pcap_t is activated");
1155 
1156 	case PCAP_ERROR_NO_SUCH_DEVICE:
1157 		return ("No such device exists");
1158 
1159 	case PCAP_ERROR_RFMON_NOTSUP:
1160 		return ("That device doesn't support monitor mode");
1161 
1162 	case PCAP_ERROR_NOT_RFMON:
1163 		return ("That operation is supported only in monitor mode");
1164 
1165 	case PCAP_ERROR_PERM_DENIED:
1166 		return ("You don't have permission to capture on that device");
1167 
1168 	case PCAP_ERROR_IFACE_NOT_UP:
1169 		return ("That device is not up");
1170 
1171 	case PCAP_ERROR_CANTSET_TSTAMP_TYPE:
1172 		return ("That device doesn't support setting the time stamp type");
1173 
1174 	case PCAP_ERROR_PROMISC_PERM_DENIED:
1175 		return ("You don't have permission to capture in promiscuous mode on that device");
1176 	}
1177 	(void)snprintf(ebuf, sizeof ebuf, "Unknown error: %d", errnum);
1178 	return(ebuf);
1179 }
1180 
1181 /*
1182  * Not all systems have strerror().
1183  */
1184 const char *
1185 pcap_strerror(int errnum)
1186 {
1187 #ifdef HAVE_STRERROR
1188 	return (strerror(errnum));
1189 #else
1190 	extern int sys_nerr;
1191 	extern const char *const sys_errlist[];
1192 	static char ebuf[15+10+1];
1193 
1194 	if ((unsigned int)errnum < sys_nerr)
1195 		return ((char *)sys_errlist[errnum]);
1196 	(void)snprintf(ebuf, sizeof ebuf, "Unknown error: %d", errnum);
1197 	return(ebuf);
1198 #endif
1199 }
1200 
1201 int
1202 pcap_setfilter(pcap_t *p, struct bpf_program *fp)
1203 {
1204 	return (p->setfilter_op(p, fp));
1205 }
1206 
1207 /*
1208  * Set direction flag, which controls whether we accept only incoming
1209  * packets, only outgoing packets, or both.
1210  * Note that, depending on the platform, some or all direction arguments
1211  * might not be supported.
1212  */
1213 int
1214 pcap_setdirection(pcap_t *p, pcap_direction_t d)
1215 {
1216 	if (p->setdirection_op == NULL) {
1217 		snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
1218 		    "Setting direction is not implemented on this platform");
1219 		return (-1);
1220 	} else
1221 		return (p->setdirection_op(p, d));
1222 }
1223 
1224 int
1225 pcap_stats(pcap_t *p, struct pcap_stat *ps)
1226 {
1227 	return (p->stats_op(p, ps));
1228 }
1229 
1230 static int
1231 pcap_stats_dead(pcap_t *p, struct pcap_stat *ps _U_)
1232 {
1233 	snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
1234 	    "Statistics aren't available from a pcap_open_dead pcap_t");
1235 	return (-1);
1236 }
1237 
1238 #ifdef WIN32
1239 int
1240 pcap_setbuff(pcap_t *p, int dim)
1241 {
1242 	return (p->setbuff_op(p, dim));
1243 }
1244 
1245 static int
1246 pcap_setbuff_dead(pcap_t *p, int dim)
1247 {
1248 	snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
1249 	    "The kernel buffer size cannot be set on a pcap_open_dead pcap_t");
1250 	return (-1);
1251 }
1252 
1253 int
1254 pcap_setmode(pcap_t *p, int mode)
1255 {
1256 	return (p->setmode_op(p, mode));
1257 }
1258 
1259 static int
1260 pcap_setmode_dead(pcap_t *p, int mode)
1261 {
1262 	snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
1263 	    "impossible to set mode on a pcap_open_dead pcap_t");
1264 	return (-1);
1265 }
1266 
1267 int
1268 pcap_setmintocopy(pcap_t *p, int size)
1269 {
1270 	return (p->setmintocopy_op(p, size));
1271 }
1272 
1273 static int
1274 pcap_setmintocopy_dead(pcap_t *p, int size)
1275 {
1276 	snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
1277 	    "The mintocopy parameter cannot be set on a pcap_open_dead pcap_t");
1278 	return (-1);
1279 }
1280 #endif
1281 
1282 /*
1283  * On some platforms, we need to clean up promiscuous or monitor mode
1284  * when we close a device - and we want that to happen even if the
1285  * application just exits without explicitl closing devices.
1286  * On those platforms, we need to register a "close all the pcaps"
1287  * routine to be called when we exit, and need to maintain a list of
1288  * pcaps that need to be closed to clean up modes.
1289  *
1290  * XXX - not thread-safe.
1291  */
1292 
1293 /*
1294  * List of pcaps on which we've done something that needs to be
1295  * cleaned up.
1296  * If there are any such pcaps, we arrange to call "pcap_close_all()"
1297  * when we exit, and have it close all of them.
1298  */
1299 static struct pcap *pcaps_to_close;
1300 
1301 /*
1302  * TRUE if we've already called "atexit()" to cause "pcap_close_all()" to
1303  * be called on exit.
1304  */
1305 static int did_atexit;
1306 
1307 static void
1308 pcap_close_all(void)
1309 {
1310 	struct pcap *handle;
1311 
1312 	while ((handle = pcaps_to_close) != NULL)
1313 		pcap_close(handle);
1314 }
1315 
1316 int
1317 pcap_do_addexit(pcap_t *p)
1318 {
1319 	/*
1320 	 * If we haven't already done so, arrange to have
1321 	 * "pcap_close_all()" called when we exit.
1322 	 */
1323 	if (!did_atexit) {
1324 		if (atexit(pcap_close_all) == -1) {
1325 			/*
1326 			 * "atexit()" failed; let our caller know.
1327 			 */
1328 			strncpy(p->errbuf, "atexit failed",
1329 			    PCAP_ERRBUF_SIZE);
1330 			return (0);
1331 		}
1332 		did_atexit = 1;
1333 	}
1334 	return (1);
1335 }
1336 
1337 void
1338 pcap_add_to_pcaps_to_close(pcap_t *p)
1339 {
1340 	p->md.next = pcaps_to_close;
1341 	pcaps_to_close = p;
1342 }
1343 
1344 void
1345 pcap_remove_from_pcaps_to_close(pcap_t *p)
1346 {
1347 	pcap_t *pc, *prevpc;
1348 
1349 	for (pc = pcaps_to_close, prevpc = NULL; pc != NULL;
1350 	    prevpc = pc, pc = pc->md.next) {
1351 		if (pc == p) {
1352 			/*
1353 			 * Found it.  Remove it from the list.
1354 			 */
1355 			if (prevpc == NULL) {
1356 				/*
1357 				 * It was at the head of the list.
1358 				 */
1359 				pcaps_to_close = pc->md.next;
1360 			} else {
1361 				/*
1362 				 * It was in the middle of the list.
1363 				 */
1364 				prevpc->md.next = pc->md.next;
1365 			}
1366 			break;
1367 		}
1368 	}
1369 }
1370 
1371 void
1372 pcap_cleanup_live_common(pcap_t *p)
1373 {
1374 	if (p->buffer != NULL) {
1375 		free(p->buffer);
1376 		p->buffer = NULL;
1377 	}
1378 	if (p->dlt_list != NULL) {
1379 		free(p->dlt_list);
1380 		p->dlt_list = NULL;
1381 		p->dlt_count = 0;
1382 	}
1383 	if (p->tstamp_type_list != NULL) {
1384 		free(p->tstamp_type_list);
1385 		p->tstamp_type_list = NULL;
1386 		p->tstamp_type_count = 0;
1387 	}
1388 	pcap_freecode(&p->fcode);
1389 #if !defined(WIN32) && !defined(MSDOS)
1390 	if (p->fd >= 0) {
1391 		close(p->fd);
1392 		p->fd = -1;
1393 	}
1394 	p->selectable_fd = -1;
1395 	p->send_fd = -1;
1396 #endif
1397 }
1398 
1399 static void
1400 pcap_cleanup_dead(pcap_t *p _U_)
1401 {
1402 	/* Nothing to do. */
1403 }
1404 
1405 pcap_t *
1406 pcap_open_dead(int linktype, int snaplen)
1407 {
1408 	pcap_t *p;
1409 
1410 	p = malloc(sizeof(*p));
1411 	if (p == NULL)
1412 		return NULL;
1413 	memset (p, 0, sizeof(*p));
1414 	p->snapshot = snaplen;
1415 	p->linktype = linktype;
1416 	p->stats_op = pcap_stats_dead;
1417 #ifdef WIN32
1418 	p->setbuff_op = pcap_setbuff_dead;
1419 	p->setmode_op = pcap_setmode_dead;
1420 	p->setmintocopy_op = pcap_setmintocopy_dead;
1421 #endif
1422 	p->cleanup_op = pcap_cleanup_dead;
1423 	p->activated = 1;
1424 	return (p);
1425 }
1426 
1427 /*
1428  * API compatible with WinPcap's "send a packet" routine - returns -1
1429  * on error, 0 otherwise.
1430  *
1431  * XXX - what if we get a short write?
1432  */
1433 int
1434 pcap_sendpacket(pcap_t *p, const u_char *buf, int size)
1435 {
1436 	if (p->inject_op(p, buf, size) == -1)
1437 		return (-1);
1438 	return (0);
1439 }
1440 
1441 /*
1442  * API compatible with OpenBSD's "send a packet" routine - returns -1 on
1443  * error, number of bytes written otherwise.
1444  */
1445 int
1446 pcap_inject(pcap_t *p, const void *buf, size_t size)
1447 {
1448 	return (p->inject_op(p, buf, size));
1449 }
1450 
1451 void
1452 pcap_close(pcap_t *p)
1453 {
1454 	if (p->opt.source != NULL)
1455 		free(p->opt.source);
1456 	p->cleanup_op(p);
1457 	free(p);
1458 }
1459 
1460 /*
1461  * Given a BPF program, a pcap_pkthdr structure for a packet, and the raw
1462  * data for the packet, check whether the packet passes the filter.
1463  * Returns the return value of the filter program, which will be zero if
1464  * the packet doesn't pass and non-zero if the packet does pass.
1465  */
1466 int
1467 pcap_offline_filter(struct bpf_program *fp, const struct pcap_pkthdr *h,
1468     const u_char *pkt)
1469 {
1470 	struct bpf_insn *fcode = fp->bf_insns;
1471 
1472 	if (fcode != NULL)
1473 		return (bpf_filter(fcode, pkt, h->len, h->caplen));
1474 	else
1475 		return (0);
1476 }
1477 
1478 /*
1479  * We make the version string static, and return a pointer to it, rather
1480  * than exporting the version string directly.  On at least some UNIXes,
1481  * if you import data from a shared library into an program, the data is
1482  * bound into the program binary, so if the string in the version of the
1483  * library with which the program was linked isn't the same as the
1484  * string in the version of the library with which the program is being
1485  * run, various undesirable things may happen (warnings, the string
1486  * being the one from the version of the library with which the program
1487  * was linked, or even weirder things, such as the string being the one
1488  * from the library but being truncated).
1489  */
1490 #ifdef HAVE_VERSION_H
1491 #include "version.h"
1492 #else
1493 static const char pcap_version_string[] = "libpcap version 1.x.y";
1494 #endif
1495 
1496 #ifdef WIN32
1497 /*
1498  * XXX - it'd be nice if we could somehow generate the WinPcap and libpcap
1499  * version numbers when building WinPcap.  (It'd be nice to do so for
1500  * the packet.dll version number as well.)
1501  */
1502 static const char wpcap_version_string[] = "4.0";
1503 static const char pcap_version_string_fmt[] =
1504     "WinPcap version %s, based on %s";
1505 static const char pcap_version_string_packet_dll_fmt[] =
1506     "WinPcap version %s (packet.dll version %s), based on %s";
1507 static char *full_pcap_version_string;
1508 
1509 const char *
1510 pcap_lib_version(void)
1511 {
1512 	char *packet_version_string;
1513 	size_t full_pcap_version_string_len;
1514 
1515 	if (full_pcap_version_string == NULL) {
1516 		/*
1517 		 * Generate the version string.
1518 		 */
1519 		packet_version_string = PacketGetVersion();
1520 		if (strcmp(wpcap_version_string, packet_version_string) == 0) {
1521 			/*
1522 			 * WinPcap version string and packet.dll version
1523 			 * string are the same; just report the WinPcap
1524 			 * version.
1525 			 */
1526 			full_pcap_version_string_len =
1527 			    (sizeof pcap_version_string_fmt - 4) +
1528 			    strlen(wpcap_version_string) +
1529 			    strlen(pcap_version_string);
1530 			full_pcap_version_string =
1531 			    malloc(full_pcap_version_string_len);
1532 			sprintf(full_pcap_version_string,
1533 			    pcap_version_string_fmt, wpcap_version_string,
1534 			    pcap_version_string);
1535 		} else {
1536 			/*
1537 			 * WinPcap version string and packet.dll version
1538 			 * string are different; that shouldn't be the
1539 			 * case (the two libraries should come from the
1540 			 * same version of WinPcap), so we report both
1541 			 * versions.
1542 			 */
1543 			full_pcap_version_string_len =
1544 			    (sizeof pcap_version_string_packet_dll_fmt - 6) +
1545 			    strlen(wpcap_version_string) +
1546 			    strlen(packet_version_string) +
1547 			    strlen(pcap_version_string);
1548 			full_pcap_version_string = malloc(full_pcap_version_string_len);
1549 
1550 			sprintf(full_pcap_version_string,
1551 			    pcap_version_string_packet_dll_fmt,
1552 			    wpcap_version_string, packet_version_string,
1553 			    pcap_version_string);
1554 		}
1555 	}
1556 	return (full_pcap_version_string);
1557 }
1558 
1559 #elif defined(MSDOS)
1560 
1561 static char *full_pcap_version_string;
1562 
1563 const char *
1564 pcap_lib_version (void)
1565 {
1566 	char *packet_version_string;
1567 	size_t full_pcap_version_string_len;
1568 	static char dospfx[] = "DOS-";
1569 
1570 	if (full_pcap_version_string == NULL) {
1571 		/*
1572 		 * Generate the version string.
1573 		 */
1574 		full_pcap_version_string_len =
1575 		    sizeof dospfx + strlen(pcap_version_string);
1576 		full_pcap_version_string =
1577 		    malloc(full_pcap_version_string_len);
1578 		strcpy(full_pcap_version_string, dospfx);
1579 		strcat(full_pcap_version_string, pcap_version_string);
1580 	}
1581 	return (full_pcap_version_string);
1582 }
1583 
1584 #else /* UN*X */
1585 
1586 const char *
1587 pcap_lib_version(void)
1588 {
1589 	return (pcap_version_string);
1590 }
1591 #endif
1592