xref: /freebsd/contrib/libpcap/pcap.c (revision 3cbb4cc200f8a0ad7ed08233425ea54524a21f1c)
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 #ifdef HAVE_CONFIG_H
35 #include <config.h>
36 #endif
37 
38 #include <pcap-types.h>
39 #ifndef _WIN32
40 #include <sys/param.h>
41 #ifndef MSDOS
42 #include <sys/file.h>
43 #endif
44 #include <sys/ioctl.h>
45 #include <sys/socket.h>
46 #ifdef HAVE_SYS_SOCKIO_H
47 #include <sys/sockio.h>
48 #endif
49 
50 struct mbuf;		/* Squelch compiler warnings on some platforms for */
51 struct rtentry;		/* declarations in <net/if.h> */
52 #include <net/if.h>
53 #include <netinet/in.h>
54 #endif /* _WIN32 */
55 
56 #include <ctype.h>
57 #include <stdio.h>
58 #include <stdlib.h>
59 #include <string.h>
60 #if !defined(_MSC_VER) && !defined(__BORLANDC__) && !defined(__MINGW32__)
61 #include <unistd.h>
62 #endif
63 #include <fcntl.h>
64 #include <errno.h>
65 #ifdef HAVE_LIMITS_H
66 #include <limits.h>
67 #else
68 #define INT_MAX		2147483647
69 #endif
70 
71 #ifdef HAVE_OS_PROTO_H
72 #include "os-proto.h"
73 #endif
74 
75 #ifdef MSDOS
76 #include "pcap-dos.h"
77 #endif
78 
79 #include "pcap-int.h"
80 
81 #include "optimize.h"
82 
83 #ifdef HAVE_DAG_API
84 #include "pcap-dag.h"
85 #endif /* HAVE_DAG_API */
86 
87 #ifdef HAVE_SEPTEL_API
88 #include "pcap-septel.h"
89 #endif /* HAVE_SEPTEL_API */
90 
91 #ifdef HAVE_SNF_API
92 #include "pcap-snf.h"
93 #endif /* HAVE_SNF_API */
94 
95 #ifdef HAVE_TC_API
96 #include "pcap-tc.h"
97 #endif /* HAVE_TC_API */
98 
99 #ifdef PCAP_SUPPORT_USB
100 #include "pcap-usb-linux.h"
101 #endif
102 
103 #ifdef PCAP_SUPPORT_BT
104 #include "pcap-bt-linux.h"
105 #endif
106 
107 #ifdef PCAP_SUPPORT_BT_MONITOR
108 #include "pcap-bt-monitor-linux.h"
109 #endif
110 
111 #ifdef PCAP_SUPPORT_NETFILTER
112 #include "pcap-netfilter-linux.h"
113 #endif
114 
115 #ifdef PCAP_SUPPORT_NETMAP
116 #include "pcap-netmap.h"
117 #endif
118 
119 #ifdef PCAP_SUPPORT_DBUS
120 #include "pcap-dbus.h"
121 #endif
122 
123 #ifdef PCAP_SUPPORT_RDMASNIFF
124 #include "pcap-rdmasniff.h"
125 #endif
126 
127 #ifdef _WIN32
128 /*
129  * DllMain(), required when built as a Windows DLL.
130  */
131 BOOL WINAPI DllMain(
132   HANDLE hinstDLL,
133   DWORD dwReason,
134   LPVOID lpvReserved
135 )
136 {
137 	return (TRUE);
138 }
139 
140 /*
141  * Start WinSock.
142  * Exported in case some applications using WinPcap/Npcap called it,
143  * even though it wasn't exported.
144  */
145 int
146 wsockinit(void)
147 {
148 	WORD wVersionRequested;
149 	WSADATA wsaData;
150 	static int err = -1;
151 	static int done = 0;
152 
153 	if (done)
154 		return (err);
155 
156 	wVersionRequested = MAKEWORD( 1, 1);
157 	err = WSAStartup( wVersionRequested, &wsaData );
158 	atexit ((void(*)(void))WSACleanup);
159 	done = 1;
160 
161 	if ( err != 0 )
162 		err = -1;
163 	return (err);
164 }
165 
166 /*
167  * This is the exported function; new programs should call this.
168  */
169 int
170 pcap_wsockinit(void)
171 {
172        return (wsockinit());
173 }
174 #endif /* _WIN32 */
175 
176 /*
177  * String containing the library version.
178  * Not explicitly exported via a header file - the right API to use
179  * is pcap_lib_version() - but some programs included it, so we
180  * provide it.
181  *
182  * We declare it here, right before defining it, to squelch any
183  * warnings we might get from compilers about the lack of a
184  * declaration.
185  */
186 PCAP_API char pcap_version[];
187 PCAP_API_DEF char pcap_version[] = PACKAGE_VERSION;
188 
189 static void
190 pcap_set_not_initialized_message(pcap_t *pcap)
191 {
192 	if (pcap->activated) {
193 		/* A module probably forgot to set the function pointer */
194 		(void)pcap_snprintf(pcap->errbuf, sizeof(pcap->errbuf),
195 		    "This operation isn't properly handled by that device");
196 		return;
197 	}
198 	/* in case the caller doesn't check for PCAP_ERROR_NOT_ACTIVATED */
199 	(void)pcap_snprintf(pcap->errbuf, sizeof(pcap->errbuf),
200 	    "This handle hasn't been activated yet");
201 }
202 
203 static int
204 pcap_read_not_initialized(pcap_t *pcap, int cnt _U_, pcap_handler callback _U_,
205     u_char *user _U_)
206 {
207 	pcap_set_not_initialized_message(pcap);
208 	/* this means 'not initialized' */
209 	return (PCAP_ERROR_NOT_ACTIVATED);
210 }
211 
212 static int
213 pcap_inject_not_initialized(pcap_t *pcap, const void * buf _U_, size_t size _U_)
214 {
215 	pcap_set_not_initialized_message(pcap);
216 	/* this means 'not initialized' */
217 	return (PCAP_ERROR_NOT_ACTIVATED);
218 }
219 
220 static int
221 pcap_setfilter_not_initialized(pcap_t *pcap, struct bpf_program *fp _U_)
222 {
223 	pcap_set_not_initialized_message(pcap);
224 	/* this means 'not initialized' */
225 	return (PCAP_ERROR_NOT_ACTIVATED);
226 }
227 
228 static int
229 pcap_setdirection_not_initialized(pcap_t *pcap, pcap_direction_t d _U_)
230 {
231 	pcap_set_not_initialized_message(pcap);
232 	/* this means 'not initialized' */
233 	return (PCAP_ERROR_NOT_ACTIVATED);
234 }
235 
236 static int
237 pcap_set_datalink_not_initialized(pcap_t *pcap, int dlt _U_)
238 {
239 	pcap_set_not_initialized_message(pcap);
240 	/* this means 'not initialized' */
241 	return (PCAP_ERROR_NOT_ACTIVATED);
242 }
243 
244 static int
245 pcap_getnonblock_not_initialized(pcap_t *pcap)
246 {
247 	pcap_set_not_initialized_message(pcap);
248 	/* this means 'not initialized' */
249 	return (PCAP_ERROR_NOT_ACTIVATED);
250 }
251 
252 static int
253 pcap_stats_not_initialized(pcap_t *pcap, struct pcap_stat *ps _U_)
254 {
255 	pcap_set_not_initialized_message(pcap);
256 	/* this means 'not initialized' */
257 	return (PCAP_ERROR_NOT_ACTIVATED);
258 }
259 
260 #ifdef _WIN32
261 struct pcap_stat *
262 pcap_stats_ex_not_initialized(pcap_t *pcap, int *pcap_stat_size _U_)
263 {
264 	pcap_set_not_initialized_message(pcap);
265 	return (NULL);
266 }
267 
268 static int
269 pcap_setbuff_not_initialized(pcap_t *pcap, int dim _U_)
270 {
271 	pcap_set_not_initialized_message(pcap);
272 	/* this means 'not initialized' */
273 	return (PCAP_ERROR_NOT_ACTIVATED);
274 }
275 
276 static int
277 pcap_setmode_not_initialized(pcap_t *pcap, int mode _U_)
278 {
279 	pcap_set_not_initialized_message(pcap);
280 	/* this means 'not initialized' */
281 	return (PCAP_ERROR_NOT_ACTIVATED);
282 }
283 
284 static int
285 pcap_setmintocopy_not_initialized(pcap_t *pcap, int size _U_)
286 {
287 	pcap_set_not_initialized_message(pcap);
288 	/* this means 'not initialized' */
289 	return (PCAP_ERROR_NOT_ACTIVATED);
290 }
291 
292 static HANDLE
293 pcap_getevent_not_initialized(pcap_t *pcap)
294 {
295 	pcap_set_not_initialized_message(pcap);
296 	return (INVALID_HANDLE_VALUE);
297 }
298 
299 static int
300 pcap_oid_get_request_not_initialized(pcap_t *pcap, bpf_u_int32 oid _U_,
301     void *data _U_, size_t *lenp _U_)
302 {
303 	pcap_set_not_initialized_message(pcap);
304 	return (PCAP_ERROR_NOT_ACTIVATED);
305 }
306 
307 static int
308 pcap_oid_set_request_not_initialized(pcap_t *pcap, bpf_u_int32 oid _U_,
309     const void *data _U_, size_t *lenp _U_)
310 {
311 	pcap_set_not_initialized_message(pcap);
312 	return (PCAP_ERROR_NOT_ACTIVATED);
313 }
314 
315 static u_int
316 pcap_sendqueue_transmit_not_initialized(pcap_t *pcap, pcap_send_queue* queue, int sync)
317 {
318 	pcap_set_not_initialized_message(pcap);
319 	return (0);
320 }
321 
322 static int
323 pcap_setuserbuffer_not_initialized(pcap_t *pcap, int size _U_)
324 {
325 	pcap_set_not_initialized_message(pcap);
326 	return (PCAP_ERROR_NOT_ACTIVATED);
327 }
328 
329 static int
330 pcap_live_dump_not_initialized(pcap_t *pcap, char *filename _U_, int maxsize _U_,
331     int maxpacks _U_)
332 {
333 	pcap_set_not_initialized_message(pcap);
334 	return (PCAP_ERROR_NOT_ACTIVATED);
335 }
336 
337 static int
338 pcap_live_dump_ended_not_initialized(pcap_t *pcap, int sync _U_)
339 {
340 	pcap_set_not_initialized_message(pcap);
341 	return (PCAP_ERROR_NOT_ACTIVATED);
342 }
343 
344 static PAirpcapHandle
345 pcap_get_airpcap_handle_not_initialized(pcap_t *pcap)
346 {
347 	pcap_set_not_initialized_message(pcap);
348 	return (NULL);
349 }
350 #endif
351 
352 /*
353  * Returns 1 if rfmon mode can be set on the pcap_t, 0 if it can't,
354  * a PCAP_ERROR value on an error.
355  */
356 int
357 pcap_can_set_rfmon(pcap_t *p)
358 {
359 	return (p->can_set_rfmon_op(p));
360 }
361 
362 /*
363  * For systems where rfmon mode is never supported.
364  */
365 static int
366 pcap_cant_set_rfmon(pcap_t *p _U_)
367 {
368 	return (0);
369 }
370 
371 /*
372  * Sets *tstamp_typesp to point to an array 1 or more supported time stamp
373  * types; the return value is the number of supported time stamp types.
374  * The list should be freed by a call to pcap_free_tstamp_types() when
375  * you're done with it.
376  *
377  * A return value of 0 means "you don't get a choice of time stamp type",
378  * in which case *tstamp_typesp is set to null.
379  *
380  * PCAP_ERROR is returned on error.
381  */
382 int
383 pcap_list_tstamp_types(pcap_t *p, int **tstamp_typesp)
384 {
385 	if (p->tstamp_type_count == 0) {
386 		/*
387 		 * We don't support multiple time stamp types.
388 		 * That means the only type we support is PCAP_TSTAMP_HOST;
389 		 * set up a list containing only that type.
390 		 */
391 		*tstamp_typesp = (int*)malloc(sizeof(**tstamp_typesp));
392 		if (*tstamp_typesp == NULL) {
393 			pcap_fmt_errmsg_for_errno(p->errbuf, sizeof(p->errbuf),
394 			    errno, "malloc");
395 			return (PCAP_ERROR);
396 		}
397 		**tstamp_typesp = PCAP_TSTAMP_HOST;
398 		return (1);
399 	} else {
400 		*tstamp_typesp = (int*)calloc(sizeof(**tstamp_typesp),
401 		    p->tstamp_type_count);
402 		if (*tstamp_typesp == NULL) {
403 			pcap_fmt_errmsg_for_errno(p->errbuf, sizeof(p->errbuf),
404 			    errno, "malloc");
405 			return (PCAP_ERROR);
406 		}
407 		(void)memcpy(*tstamp_typesp, p->tstamp_type_list,
408 		    sizeof(**tstamp_typesp) * p->tstamp_type_count);
409 		return (p->tstamp_type_count);
410 	}
411 }
412 
413 /*
414  * In Windows, you might have a library built with one version of the
415  * C runtime library and an application built with another version of
416  * the C runtime library, which means that the library might use one
417  * version of malloc() and free() and the application might use another
418  * version of malloc() and free().  If so, that means something
419  * allocated by the library cannot be freed by the application, so we
420  * need to have a pcap_free_tstamp_types() routine to free up the list
421  * allocated by pcap_list_tstamp_types(), even though it's just a wrapper
422  * around free().
423  */
424 void
425 pcap_free_tstamp_types(int *tstamp_type_list)
426 {
427 	free(tstamp_type_list);
428 }
429 
430 /*
431  * Default one-shot callback; overridden for capture types where the
432  * packet data cannot be guaranteed to be available after the callback
433  * returns, so that a copy must be made.
434  */
435 void
436 pcap_oneshot(u_char *user, const struct pcap_pkthdr *h, const u_char *pkt)
437 {
438 	struct oneshot_userdata *sp = (struct oneshot_userdata *)user;
439 
440 	*sp->hdr = *h;
441 	*sp->pkt = pkt;
442 }
443 
444 const u_char *
445 pcap_next(pcap_t *p, struct pcap_pkthdr *h)
446 {
447 	struct oneshot_userdata s;
448 	const u_char *pkt;
449 
450 	s.hdr = h;
451 	s.pkt = &pkt;
452 	s.pd = p;
453 	if (pcap_dispatch(p, 1, p->oneshot_callback, (u_char *)&s) <= 0)
454 		return (0);
455 	return (pkt);
456 }
457 
458 int
459 pcap_next_ex(pcap_t *p, struct pcap_pkthdr **pkt_header,
460     const u_char **pkt_data)
461 {
462 	struct oneshot_userdata s;
463 
464 	s.hdr = &p->pcap_header;
465 	s.pkt = pkt_data;
466 	s.pd = p;
467 
468 	/* Saves a pointer to the packet headers */
469 	*pkt_header= &p->pcap_header;
470 
471 	if (p->rfile != NULL) {
472 		int status;
473 
474 		/* We are on an offline capture */
475 		status = pcap_offline_read(p, 1, p->oneshot_callback,
476 		    (u_char *)&s);
477 
478 		/*
479 		 * Return codes for pcap_offline_read() are:
480 		 *   -  0: EOF
481 		 *   - -1: error
482 		 *   - >1: OK
483 		 * The first one ('0') conflicts with the return code of
484 		 * 0 from pcap_read() meaning "no packets arrived before
485 		 * the timeout expired", so we map it to -2 so you can
486 		 * distinguish between an EOF from a savefile and a
487 		 * "no packets arrived before the timeout expired, try
488 		 * again" from a live capture.
489 		 */
490 		if (status == 0)
491 			return (-2);
492 		else
493 			return (status);
494 	}
495 
496 	/*
497 	 * Return codes for pcap_read() are:
498 	 *   -  0: timeout
499 	 *   - -1: error
500 	 *   - -2: loop was broken out of with pcap_breakloop()
501 	 *   - >1: OK
502 	 * The first one ('0') conflicts with the return code of 0 from
503 	 * pcap_offline_read() meaning "end of file".
504 	*/
505 	return (p->read_op(p, 1, p->oneshot_callback, (u_char *)&s));
506 }
507 
508 /*
509  * Implementation of a pcap_if_list_t.
510  */
511 struct pcap_if_list {
512 	pcap_if_t *beginning;
513 };
514 
515 static struct capture_source_type {
516 	int (*findalldevs_op)(pcap_if_list_t *, char *);
517 	pcap_t *(*create_op)(const char *, char *, int *);
518 } capture_source_types[] = {
519 #ifdef HAVE_DAG_API
520 	{ dag_findalldevs, dag_create },
521 #endif
522 #ifdef HAVE_SEPTEL_API
523 	{ septel_findalldevs, septel_create },
524 #endif
525 #ifdef HAVE_SNF_API
526 	{ snf_findalldevs, snf_create },
527 #endif
528 #ifdef HAVE_TC_API
529 	{ TcFindAllDevs, TcCreate },
530 #endif
531 #ifdef PCAP_SUPPORT_BT
532 	{ bt_findalldevs, bt_create },
533 #endif
534 #ifdef PCAP_SUPPORT_BT_MONITOR
535 	{ bt_monitor_findalldevs, bt_monitor_create },
536 #endif
537 #ifdef PCAP_SUPPORT_USB
538 	{ usb_findalldevs, usb_create },
539 #endif
540 #ifdef PCAP_SUPPORT_NETFILTER
541 	{ netfilter_findalldevs, netfilter_create },
542 #endif
543 #ifdef PCAP_SUPPORT_NETMAP
544 	{ pcap_netmap_findalldevs, pcap_netmap_create },
545 #endif
546 #ifdef PCAP_SUPPORT_DBUS
547 	{ dbus_findalldevs, dbus_create },
548 #endif
549 #ifdef PCAP_SUPPORT_RDMASNIFF
550 	{ rdmasniff_findalldevs, rdmasniff_create },
551 #endif
552 	{ NULL, NULL }
553 };
554 
555 /*
556  * Get a list of all capture sources that are up and that we can open.
557  * Returns -1 on error, 0 otherwise.
558  * The list, as returned through "alldevsp", may be null if no interfaces
559  * were up and could be opened.
560  */
561 int
562 pcap_findalldevs(pcap_if_t **alldevsp, char *errbuf)
563 {
564 	size_t i;
565 	pcap_if_list_t devlist;
566 
567 	/*
568 	 * Find all the local network interfaces on which we
569 	 * can capture.
570 	 */
571 	devlist.beginning = NULL;
572 	if (pcap_platform_finddevs(&devlist, errbuf) == -1) {
573 		/*
574 		 * Failed - free all of the entries we were given
575 		 * before we failed.
576 		 */
577 		if (devlist.beginning != NULL)
578 			pcap_freealldevs(devlist.beginning);
579 		*alldevsp = NULL;
580 		return (-1);
581 	}
582 
583 	/*
584 	 * Ask each of the non-local-network-interface capture
585 	 * source types what interfaces they have.
586 	 */
587 	for (i = 0; capture_source_types[i].findalldevs_op != NULL; i++) {
588 		if (capture_source_types[i].findalldevs_op(&devlist, errbuf) == -1) {
589 			/*
590 			 * We had an error; free the list we've been
591 			 * constructing.
592 			 */
593 			if (devlist.beginning != NULL)
594 				pcap_freealldevs(devlist.beginning);
595 			*alldevsp = NULL;
596 			return (-1);
597 		}
598 	}
599 
600 	/*
601 	 * Return the first entry of the list of all devices.
602 	 */
603 	*alldevsp = devlist.beginning;
604 	return (0);
605 }
606 
607 static struct sockaddr *
608 dup_sockaddr(struct sockaddr *sa, size_t sa_length)
609 {
610 	struct sockaddr *newsa;
611 
612 	if ((newsa = malloc(sa_length)) == NULL)
613 		return (NULL);
614 	return (memcpy(newsa, sa, sa_length));
615 }
616 
617 /*
618  * Construct a "figure of merit" for an interface, for use when sorting
619  * the list of interfaces, in which interfaces that are up are superior
620  * to interfaces that aren't up, interfaces that are up and running are
621  * superior to interfaces that are up but not running, and non-loopback
622  * interfaces that are up and running are superior to loopback interfaces,
623  * and interfaces with the same flags have a figure of merit that's higher
624  * the lower the instance number.
625  *
626  * The goal is to try to put the interfaces most likely to be useful for
627  * capture at the beginning of the list.
628  *
629  * The figure of merit, which is lower the "better" the interface is,
630  * has the uppermost bit set if the interface isn't running, the bit
631  * below that set if the interface isn't up, the bit below that set
632  * if the interface is a loopback interface, and the interface index
633  * in the 29 bits below that.  (Yes, we assume u_int is 32 bits.)
634  */
635 static u_int
636 get_figure_of_merit(pcap_if_t *dev)
637 {
638 	const char *cp;
639 	u_int n;
640 
641 	if (strcmp(dev->name, "any") == 0) {
642 		/*
643 		 * Give the "any" device an artificially high instance
644 		 * number, so it shows up after all other non-loopback
645 		 * interfaces.
646 		 */
647 		n = 0x1FFFFFFF;	/* 29 all-1 bits */
648 	} else {
649 		/*
650 		 * A number at the end of the device name string is
651 		 * assumed to be an instance number.  Add 1 to the
652 		 * instance number, and use 0 for "no instance
653 		 * number", so we don't put "no instance number"
654 		 * devices and "instance 0" devices together.
655 		 */
656 		cp = dev->name + strlen(dev->name) - 1;
657 		while (cp-1 >= dev->name && *(cp-1) >= '0' && *(cp-1) <= '9')
658 			cp--;
659 		if (*cp >= '0' && *cp <= '9')
660 			n = atoi(cp) + 1;
661 		else
662 			n = 0;
663 	}
664 	if (!(dev->flags & PCAP_IF_RUNNING))
665 		n |= 0x80000000;
666 	if (!(dev->flags & PCAP_IF_UP))
667 		n |= 0x40000000;
668 
669 	/*
670 	 * Give non-wireless interfaces that aren't disconnected a better
671 	 * figure of merit than interfaces that are disconnected, as
672 	 * "disconnected" should indicate that the interface isn't
673 	 * plugged into a network and thus won't give you any traffic.
674 	 *
675 	 * For wireless interfaces, it means "associated with a network",
676 	 * which we presume not to necessarily prevent capture, as you
677 	 * might run the adapter in some flavor of monitor mode.
678 	 */
679 	if (!(dev->flags & PCAP_IF_WIRELESS) &&
680 	    (dev->flags & PCAP_IF_CONNECTION_STATUS) == PCAP_IF_CONNECTION_STATUS_DISCONNECTED)
681 		n |= 0x20000000;
682 
683 	/*
684 	 * Sort loopback devices after non-loopback devices, *except* for
685 	 * disconnected devices.
686 	 */
687 	if (dev->flags & PCAP_IF_LOOPBACK)
688 		n |= 0x10000000;
689 
690 	return (n);
691 }
692 
693 #ifndef _WIN32
694 /*
695  * Try to get a description for a given device.
696  * Returns a mallocated description if it could and NULL if it couldn't.
697  *
698  * XXX - on FreeBSDs that support it, should it get the sysctl named
699  * "dev.{adapter family name}.{adapter unit}.%desc" to get a description
700  * of the adapter?  Note that "dev.an.0.%desc" is "Aironet PC4500/PC4800"
701  * with my Cisco 350 card, so the name isn't entirely descriptive.  The
702  * "dev.an.0.%pnpinfo" has a better description, although one might argue
703  * that the problem is really a driver bug - if it can find out that it's
704  * a Cisco 340 or 350, rather than an old Aironet card, it should use
705  * that in the description.
706  *
707  * Do NetBSD, DragonflyBSD, or OpenBSD support this as well?  FreeBSD
708  * and OpenBSD let you get a description, but it's not generated by the OS,
709  * it's set with another ioctl that ifconfig supports; we use that to get
710  * a description in FreeBSD and OpenBSD, but if there is no such
711  * description available, it still might be nice to get some description
712  * string based on the device type or something such as that.
713  *
714  * In macOS, the System Configuration framework can apparently return
715  * names in 10.4 and later.
716  *
717  * It also appears that freedesktop.org's HAL offers an "info.product"
718  * string, but the HAL specification says it "should not be used in any
719  * UI" and "subsystem/capability specific properties" should be used
720  * instead and, in any case, I think HAL is being deprecated in
721  * favor of other stuff such as DeviceKit.  DeviceKit doesn't appear
722  * to have any obvious product information for devices, but maybe
723  * I haven't looked hard enough.
724  *
725  * Using the System Configuration framework, or HAL, or DeviceKit, or
726  * whatever, would require that libpcap applications be linked with
727  * the frameworks/libraries in question.  That shouldn't be a problem
728  * for programs linking with the shared version of libpcap (unless
729  * you're running on AIX - which I think is the only UN*X that doesn't
730  * support linking a shared library with other libraries on which it
731  * depends, and having an executable linked only with the first shared
732  * library automatically pick up the other libraries when started -
733  * and using HAL or whatever).  Programs linked with the static
734  * version of libpcap would have to use pcap-config with the --static
735  * flag in order to get the right linker flags in order to pick up
736  * the additional libraries/frameworks; those programs need that anyway
737  * for libpcap 1.1 and beyond on Linux, as, by default, it requires
738  * -lnl.
739  *
740  * Do any other UN*Xes, or desktop environments support getting a
741  * description?
742  */
743 static char *
744 #ifdef SIOCGIFDESCR
745 get_if_description(const char *name)
746 {
747 	char *description = NULL;
748 	int s;
749 	struct ifreq ifrdesc;
750 #ifndef IFDESCRSIZE
751 	size_t descrlen = 64;
752 #else
753 	size_t descrlen = IFDESCRSIZE;
754 #endif /* IFDESCRSIZE */
755 
756 	/*
757 	 * Get the description for the interface.
758 	 */
759 	memset(&ifrdesc, 0, sizeof ifrdesc);
760 	pcap_strlcpy(ifrdesc.ifr_name, name, sizeof ifrdesc.ifr_name);
761 	s = socket(AF_INET, SOCK_DGRAM, 0);
762 	if (s >= 0) {
763 #ifdef __FreeBSD__
764 		/*
765 		 * On FreeBSD, if the buffer isn't big enough for the
766 		 * description, the ioctl succeeds, but the description
767 		 * isn't copied, ifr_buffer.length is set to the description
768 		 * length, and ifr_buffer.buffer is set to NULL.
769 		 */
770 		for (;;) {
771 			free(description);
772 			if ((description = malloc(descrlen)) != NULL) {
773 				ifrdesc.ifr_buffer.buffer = description;
774 				ifrdesc.ifr_buffer.length = descrlen;
775 				if (ioctl(s, SIOCGIFDESCR, &ifrdesc) == 0) {
776 					if (ifrdesc.ifr_buffer.buffer ==
777 					    description)
778 						break;
779 					else
780 						descrlen = ifrdesc.ifr_buffer.length;
781 				} else {
782 					/*
783 					 * Failed to get interface description.
784 					 */
785 					free(description);
786 					description = NULL;
787 					break;
788 				}
789 			} else
790 				break;
791 		}
792 #else /* __FreeBSD__ */
793 		/*
794 		 * The only other OS that currently supports
795 		 * SIOCGIFDESCR is OpenBSD, and it has no way
796 		 * to get the description length - it's clamped
797 		 * to a maximum of IFDESCRSIZE.
798 		 */
799 		if ((description = malloc(descrlen)) != NULL) {
800 			ifrdesc.ifr_data = (caddr_t)description;
801 			if (ioctl(s, SIOCGIFDESCR, &ifrdesc) != 0) {
802 				/*
803 				 * Failed to get interface description.
804 				 */
805 				free(description);
806 				description = NULL;
807 			}
808 		}
809 #endif /* __FreeBSD__ */
810 		close(s);
811 		if (description != NULL && description[0] == '\0') {
812 			/*
813 			 * Description is empty, so discard it.
814 			 */
815 			free(description);
816 			description = NULL;
817 		}
818 	}
819 
820 #ifdef __FreeBSD__
821 	/*
822 	 * For FreeBSD, if we didn't get a description, and this is
823 	 * a device with a name of the form usbusN, label it as a USB
824 	 * bus.
825 	 */
826 	if (description == NULL) {
827 		if (strncmp(name, "usbus", 5) == 0) {
828 			/*
829 			 * OK, it begins with "usbus".
830 			 */
831 			long busnum;
832 			char *p;
833 
834 			errno = 0;
835 			busnum = strtol(name + 5, &p, 10);
836 			if (errno == 0 && p != name + 5 && *p == '\0' &&
837 			    busnum >= 0 && busnum <= INT_MAX) {
838 				/*
839 				 * OK, it's a valid number that's not
840 				 * bigger than INT_MAX.  Construct
841 				 * a description from it.
842 				 * (If that fails, we don't worry about
843 				 * it, we just return NULL.)
844 				 */
845 				if (pcap_asprintf(&description,
846 				    "USB bus number %ld", busnum) == -1) {
847 					/* Failed. */
848 					description = NULL;
849 				}
850 			}
851 		}
852 	}
853 #endif
854 	return (description);
855 #else /* SIOCGIFDESCR */
856 get_if_description(const char *name _U_)
857 {
858 	return (NULL);
859 #endif /* SIOCGIFDESCR */
860 }
861 
862 /*
863  * Look for a given device in the specified list of devices.
864  *
865  * If we find it, return a pointer to its entry.
866  *
867  * If we don't find it, attempt to add an entry for it, with the specified
868  * IFF_ flags and description, and, if that succeeds, return a pointer to
869  * the new entry, otherwise return NULL and set errbuf to an error message.
870  */
871 pcap_if_t *
872 find_or_add_if(pcap_if_list_t *devlistp, const char *name,
873     bpf_u_int32 if_flags, get_if_flags_func get_flags_func, char *errbuf)
874 {
875 	bpf_u_int32 pcap_flags;
876 
877 	/*
878 	 * Convert IFF_ flags to pcap flags.
879 	 */
880 	pcap_flags = 0;
881 #ifdef IFF_LOOPBACK
882 	if (if_flags & IFF_LOOPBACK)
883 		pcap_flags |= PCAP_IF_LOOPBACK;
884 #else
885 	/*
886 	 * We don't have IFF_LOOPBACK, so look at the device name to
887 	 * see if it looks like a loopback device.
888 	 */
889 	if (name[0] == 'l' && name[1] == 'o' &&
890 	    (isdigit((unsigned char)(name[2])) || name[2] == '\0')
891 		pcap_flags |= PCAP_IF_LOOPBACK;
892 #endif
893 #ifdef IFF_UP
894 	if (if_flags & IFF_UP)
895 		pcap_flags |= PCAP_IF_UP;
896 #endif
897 #ifdef IFF_RUNNING
898 	if (if_flags & IFF_RUNNING)
899 		pcap_flags |= PCAP_IF_RUNNING;
900 #endif
901 
902 	/*
903 	 * Attempt to find an entry for this device; if we don't find one,
904 	 * attempt to add one.
905 	 */
906 	return (find_or_add_dev(devlistp, name, pcap_flags,
907 	    get_flags_func, get_if_description(name), errbuf));
908 }
909 
910 /*
911  * Look for a given device in the specified list of devices.
912  *
913  * If we find it, then, if the specified address isn't null, add it to
914  * the list of addresses for the device and return 0.
915  *
916  * If we don't find it, attempt to add an entry for it, with the specified
917  * IFF_ flags and description, and, if that succeeds, add the specified
918  * address to its list of addresses if that address is non-null, and
919  * return 0, otherwise return -1 and set errbuf to an error message.
920  *
921  * (We can get called with a null address because we might get a list
922  * of interface name/address combinations from the underlying OS, with
923  * the address being absent in some cases, rather than a list of
924  * interfaces with each interface having a list of addresses, so this
925  * call may be the only call made to add to the list, and we want to
926  * add interfaces even if they have no addresses.)
927  */
928 int
929 add_addr_to_if(pcap_if_list_t *devlistp, const char *name,
930     bpf_u_int32 if_flags, get_if_flags_func get_flags_func,
931     struct sockaddr *addr, size_t addr_size,
932     struct sockaddr *netmask, size_t netmask_size,
933     struct sockaddr *broadaddr, size_t broadaddr_size,
934     struct sockaddr *dstaddr, size_t dstaddr_size,
935     char *errbuf)
936 {
937 	pcap_if_t *curdev;
938 
939 	/*
940 	 * Check whether the device exists and, if not, add it.
941 	 */
942 	curdev = find_or_add_if(devlistp, name, if_flags, get_flags_func,
943 	    errbuf);
944 	if (curdev == NULL) {
945 		/*
946 		 * Error - give up.
947 		 */
948 		return (-1);
949 	}
950 
951 	if (addr == NULL) {
952 		/*
953 		 * There's no address to add; this entry just meant
954 		 * "here's a new interface".
955 		 */
956 		return (0);
957 	}
958 
959 	/*
960 	 * "curdev" is an entry for this interface, and we have an
961 	 * address for it; add an entry for that address to the
962 	 * interface's list of addresses.
963 	 */
964 	return (add_addr_to_dev(curdev, addr, addr_size, netmask,
965 	    netmask_size, broadaddr, broadaddr_size, dstaddr,
966 	    dstaddr_size, errbuf));
967 }
968 #endif /* _WIN32 */
969 
970 /*
971  * Add an entry to the list of addresses for an interface.
972  * "curdev" is the entry for that interface.
973  */
974 int
975 add_addr_to_dev(pcap_if_t *curdev,
976     struct sockaddr *addr, size_t addr_size,
977     struct sockaddr *netmask, size_t netmask_size,
978     struct sockaddr *broadaddr, size_t broadaddr_size,
979     struct sockaddr *dstaddr, size_t dstaddr_size,
980     char *errbuf)
981 {
982 	pcap_addr_t *curaddr, *prevaddr, *nextaddr;
983 
984 	/*
985 	 * Allocate the new entry and fill it in.
986 	 */
987 	curaddr = (pcap_addr_t *)malloc(sizeof(pcap_addr_t));
988 	if (curaddr == NULL) {
989 		pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
990 		    errno, "malloc");
991 		return (-1);
992 	}
993 
994 	curaddr->next = NULL;
995 	if (addr != NULL && addr_size != 0) {
996 		curaddr->addr = (struct sockaddr *)dup_sockaddr(addr, addr_size);
997 		if (curaddr->addr == NULL) {
998 			pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
999 			    errno, "malloc");
1000 			free(curaddr);
1001 			return (-1);
1002 		}
1003 	} else
1004 		curaddr->addr = NULL;
1005 
1006 	if (netmask != NULL && netmask_size != 0) {
1007 		curaddr->netmask = (struct sockaddr *)dup_sockaddr(netmask, netmask_size);
1008 		if (curaddr->netmask == NULL) {
1009 			pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
1010 			    errno, "malloc");
1011 			if (curaddr->addr != NULL)
1012 				free(curaddr->addr);
1013 			free(curaddr);
1014 			return (-1);
1015 		}
1016 	} else
1017 		curaddr->netmask = NULL;
1018 
1019 	if (broadaddr != NULL && broadaddr_size != 0) {
1020 		curaddr->broadaddr = (struct sockaddr *)dup_sockaddr(broadaddr, broadaddr_size);
1021 		if (curaddr->broadaddr == NULL) {
1022 			pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
1023 			    errno, "malloc");
1024 			if (curaddr->netmask != NULL)
1025 				free(curaddr->netmask);
1026 			if (curaddr->addr != NULL)
1027 				free(curaddr->addr);
1028 			free(curaddr);
1029 			return (-1);
1030 		}
1031 	} else
1032 		curaddr->broadaddr = NULL;
1033 
1034 	if (dstaddr != NULL && dstaddr_size != 0) {
1035 		curaddr->dstaddr = (struct sockaddr *)dup_sockaddr(dstaddr, dstaddr_size);
1036 		if (curaddr->dstaddr == NULL) {
1037 			pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
1038 			    errno, "malloc");
1039 			if (curaddr->broadaddr != NULL)
1040 				free(curaddr->broadaddr);
1041 			if (curaddr->netmask != NULL)
1042 				free(curaddr->netmask);
1043 			if (curaddr->addr != NULL)
1044 				free(curaddr->addr);
1045 			free(curaddr);
1046 			return (-1);
1047 		}
1048 	} else
1049 		curaddr->dstaddr = NULL;
1050 
1051 	/*
1052 	 * Find the end of the list of addresses.
1053 	 */
1054 	for (prevaddr = curdev->addresses; prevaddr != NULL; prevaddr = nextaddr) {
1055 		nextaddr = prevaddr->next;
1056 		if (nextaddr == NULL) {
1057 			/*
1058 			 * This is the end of the list.
1059 			 */
1060 			break;
1061 		}
1062 	}
1063 
1064 	if (prevaddr == NULL) {
1065 		/*
1066 		 * The list was empty; this is the first member.
1067 		 */
1068 		curdev->addresses = curaddr;
1069 	} else {
1070 		/*
1071 		 * "prevaddr" is the last member of the list; append
1072 		 * this member to it.
1073 		 */
1074 		prevaddr->next = curaddr;
1075 	}
1076 
1077 	return (0);
1078 }
1079 
1080 /*
1081  * Look for a given device in the specified list of devices.
1082  *
1083  * If we find it, return 0 and set *curdev_ret to point to it.
1084  *
1085  * If we don't find it, attempt to add an entry for it, with the specified
1086  * flags and description, and, if that succeeds, return 0, otherwise
1087  * return -1 and set errbuf to an error message.
1088  */
1089 pcap_if_t *
1090 find_or_add_dev(pcap_if_list_t *devlistp, const char *name, bpf_u_int32 flags,
1091     get_if_flags_func get_flags_func, const char *description, char *errbuf)
1092 {
1093 	pcap_if_t *curdev;
1094 
1095 	/*
1096 	 * Is there already an entry in the list for this device?
1097 	 */
1098 	curdev = find_dev(devlistp, name);
1099 	if (curdev != NULL) {
1100 		/*
1101 		 * Yes, return it.
1102 		 */
1103 		return (curdev);
1104 	}
1105 
1106 	/*
1107 	 * No, we didn't find it.
1108 	 */
1109 
1110 	/*
1111 	 * Try to get additional flags for the device.
1112 	 */
1113 	if ((*get_flags_func)(name, &flags, errbuf) == -1) {
1114 		/*
1115 		 * Failed.
1116 		 */
1117 		return (NULL);
1118 	}
1119 
1120 	/*
1121 	 * Now, try to add it to the list of devices.
1122 	 */
1123 	return (add_dev(devlistp, name, flags, description, errbuf));
1124 }
1125 
1126 /*
1127  * Look for a given device in the specified list of devices, and return
1128  * the entry for it if we find it or NULL if we don't.
1129  */
1130 pcap_if_t *
1131 find_dev(pcap_if_list_t *devlistp, const char *name)
1132 {
1133 	pcap_if_t *curdev;
1134 
1135 	/*
1136 	 * Is there an entry in the list for this device?
1137 	 */
1138 	for (curdev = devlistp->beginning; curdev != NULL;
1139 	    curdev = curdev->next) {
1140 		if (strcmp(name, curdev->name) == 0) {
1141 			/*
1142 			 * We found it, so, yes, there is.  No need to
1143 			 * add it.  Provide the entry we found to our
1144 			 * caller.
1145 			 */
1146 			return (curdev);
1147 		}
1148 	}
1149 
1150 	/*
1151 	 * No.
1152 	 */
1153 	return (NULL);
1154 }
1155 
1156 /*
1157  * Attempt to add an entry for a device, with the specified flags
1158  * and description, and, if that succeeds, return 0 and return a pointer
1159  * to the new entry, otherwise return NULL and set errbuf to an error
1160  * message.
1161  *
1162  * If we weren't given a description, try to get one.
1163  */
1164 pcap_if_t *
1165 add_dev(pcap_if_list_t *devlistp, const char *name, bpf_u_int32 flags,
1166     const char *description, char *errbuf)
1167 {
1168 	pcap_if_t *curdev, *prevdev, *nextdev;
1169 	u_int this_figure_of_merit, nextdev_figure_of_merit;
1170 
1171 	curdev = malloc(sizeof(pcap_if_t));
1172 	if (curdev == NULL) {
1173 		pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
1174 		    errno, "malloc");
1175 		return (NULL);
1176 	}
1177 
1178 	/*
1179 	 * Fill in the entry.
1180 	 */
1181 	curdev->next = NULL;
1182 	curdev->name = strdup(name);
1183 	if (curdev->name == NULL) {
1184 		pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
1185 		    errno, "malloc");
1186 		free(curdev);
1187 		return (NULL);
1188 	}
1189 	if (description == NULL) {
1190 		/*
1191 		 * We weren't handed a description for the interface.
1192 		 */
1193 		curdev->description = NULL;
1194 	} else {
1195 		/*
1196 		 * We were handed a description; make a copy.
1197 		 */
1198 		curdev->description = strdup(description);
1199 		if (curdev->description == NULL) {
1200 			pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
1201 			    errno, "malloc");
1202 			free(curdev->name);
1203 			free(curdev);
1204 			return (NULL);
1205 		}
1206 	}
1207 	curdev->addresses = NULL;	/* list starts out as empty */
1208 	curdev->flags = flags;
1209 
1210 	/*
1211 	 * Add it to the list, in the appropriate location.
1212 	 * First, get the "figure of merit" for this interface.
1213 	 */
1214 	this_figure_of_merit = get_figure_of_merit(curdev);
1215 
1216 	/*
1217 	 * Now look for the last interface with an figure of merit
1218 	 * less than or equal to the new interface's figure of merit.
1219 	 *
1220 	 * We start with "prevdev" being NULL, meaning we're before
1221 	 * the first element in the list.
1222 	 */
1223 	prevdev = NULL;
1224 	for (;;) {
1225 		/*
1226 		 * Get the interface after this one.
1227 		 */
1228 		if (prevdev == NULL) {
1229 			/*
1230 			 * The next element is the first element.
1231 			 */
1232 			nextdev = devlistp->beginning;
1233 		} else
1234 			nextdev = prevdev->next;
1235 
1236 		/*
1237 		 * Are we at the end of the list?
1238 		 */
1239 		if (nextdev == NULL) {
1240 			/*
1241 			 * Yes - we have to put the new entry after "prevdev".
1242 			 */
1243 			break;
1244 		}
1245 
1246 		/*
1247 		 * Is the new interface's figure of merit less
1248 		 * than the next interface's figure of merit,
1249 		 * meaning that the new interface is better
1250 		 * than the next interface?
1251 		 */
1252 		nextdev_figure_of_merit = get_figure_of_merit(nextdev);
1253 		if (this_figure_of_merit < nextdev_figure_of_merit) {
1254 			/*
1255 			 * Yes - we should put the new entry
1256 			 * before "nextdev", i.e. after "prevdev".
1257 			 */
1258 			break;
1259 		}
1260 
1261 		prevdev = nextdev;
1262 	}
1263 
1264 	/*
1265 	 * Insert before "nextdev".
1266 	 */
1267 	curdev->next = nextdev;
1268 
1269 	/*
1270 	 * Insert after "prevdev" - unless "prevdev" is null,
1271 	 * in which case this is the first interface.
1272 	 */
1273 	if (prevdev == NULL) {
1274 		/*
1275 		 * This is the first interface.  Make it
1276 		 * the first element in the list of devices.
1277 		 */
1278 		devlistp->beginning = curdev;
1279 	} else
1280 		prevdev->next = curdev;
1281 	return (curdev);
1282 }
1283 
1284 /*
1285  * Free a list of interfaces.
1286  */
1287 void
1288 pcap_freealldevs(pcap_if_t *alldevs)
1289 {
1290 	pcap_if_t *curdev, *nextdev;
1291 	pcap_addr_t *curaddr, *nextaddr;
1292 
1293 	for (curdev = alldevs; curdev != NULL; curdev = nextdev) {
1294 		nextdev = curdev->next;
1295 
1296 		/*
1297 		 * Free all addresses.
1298 		 */
1299 		for (curaddr = curdev->addresses; curaddr != NULL; curaddr = nextaddr) {
1300 			nextaddr = curaddr->next;
1301 			if (curaddr->addr)
1302 				free(curaddr->addr);
1303 			if (curaddr->netmask)
1304 				free(curaddr->netmask);
1305 			if (curaddr->broadaddr)
1306 				free(curaddr->broadaddr);
1307 			if (curaddr->dstaddr)
1308 				free(curaddr->dstaddr);
1309 			free(curaddr);
1310 		}
1311 
1312 		/*
1313 		 * Free the name string.
1314 		 */
1315 		free(curdev->name);
1316 
1317 		/*
1318 		 * Free the description string, if any.
1319 		 */
1320 		if (curdev->description != NULL)
1321 			free(curdev->description);
1322 
1323 		/*
1324 		 * Free the interface.
1325 		 */
1326 		free(curdev);
1327 	}
1328 }
1329 
1330 /*
1331  * pcap-npf.c has its own pcap_lookupdev(), for compatibility reasons, as
1332  * it actually returns the names of all interfaces, with a NUL separator
1333  * between them; some callers may depend on that.
1334  *
1335  * MS-DOS has its own pcap_lookupdev(), but that might be useful only
1336  * as an optimization.
1337  *
1338  * In all other cases, we just use pcap_findalldevs() to get a list of
1339  * devices, and pick from that list.
1340  */
1341 #if !defined(HAVE_PACKET32) && !defined(MSDOS)
1342 /*
1343  * Return the name of a network interface attached to the system, or NULL
1344  * if none can be found.  The interface must be configured up; the
1345  * lowest unit number is preferred; loopback is ignored.
1346  */
1347 char *
1348 pcap_lookupdev(char *errbuf)
1349 {
1350 	pcap_if_t *alldevs;
1351 #ifdef _WIN32
1352   /*
1353    * Windows - use the same size as the old WinPcap 3.1 code.
1354    * XXX - this is probably bigger than it needs to be.
1355    */
1356   #define IF_NAMESIZE 8192
1357 #else
1358   /*
1359    * UN*X - use the system's interface name size.
1360    * XXX - that might not be large enough for capture devices
1361    * that aren't regular network interfaces.
1362    */
1363   /* for old BSD systems, including bsdi3 */
1364   #ifndef IF_NAMESIZE
1365   #define IF_NAMESIZE IFNAMSIZ
1366   #endif
1367 #endif
1368 	static char device[IF_NAMESIZE + 1];
1369 	char *ret;
1370 
1371 	if (pcap_findalldevs(&alldevs, errbuf) == -1)
1372 		return (NULL);
1373 
1374 	if (alldevs == NULL || (alldevs->flags & PCAP_IF_LOOPBACK)) {
1375 		/*
1376 		 * There are no devices on the list, or the first device
1377 		 * on the list is a loopback device, which means there
1378 		 * are no non-loopback devices on the list.  This means
1379 		 * we can't return any device.
1380 		 *
1381 		 * XXX - why not return a loopback device?  If we can't
1382 		 * capture on it, it won't be on the list, and if it's
1383 		 * on the list, there aren't any non-loopback devices,
1384 		 * so why not just supply it as the default device?
1385 		 */
1386 		(void)pcap_strlcpy(errbuf, "no suitable device found",
1387 		    PCAP_ERRBUF_SIZE);
1388 		ret = NULL;
1389 	} else {
1390 		/*
1391 		 * Return the name of the first device on the list.
1392 		 */
1393 		(void)pcap_strlcpy(device, alldevs->name, sizeof(device));
1394 		ret = device;
1395 	}
1396 
1397 	pcap_freealldevs(alldevs);
1398 	return (ret);
1399 }
1400 #endif /* !defined(HAVE_PACKET32) && !defined(MSDOS) */
1401 
1402 #if !defined(_WIN32) && !defined(MSDOS)
1403 /*
1404  * We don't just fetch the entire list of devices, search for the
1405  * particular device, and use its first IPv4 address, as that's too
1406  * much work to get just one device's netmask.
1407  *
1408  * If we had an API to get attributes for a given device, we could
1409  * use that.
1410  */
1411 int
1412 pcap_lookupnet(const char *device, bpf_u_int32 *netp, bpf_u_int32 *maskp,
1413     char *errbuf)
1414 {
1415 	register int fd;
1416 	register struct sockaddr_in *sin4;
1417 	struct ifreq ifr;
1418 
1419 	/*
1420 	 * The pseudo-device "any" listens on all interfaces and therefore
1421 	 * has the network address and -mask "0.0.0.0" therefore catching
1422 	 * all traffic. Using NULL for the interface is the same as "any".
1423 	 */
1424 	if (!device || strcmp(device, "any") == 0
1425 #ifdef HAVE_DAG_API
1426 	    || strstr(device, "dag") != NULL
1427 #endif
1428 #ifdef HAVE_SEPTEL_API
1429 	    || strstr(device, "septel") != NULL
1430 #endif
1431 #ifdef PCAP_SUPPORT_BT
1432 	    || strstr(device, "bluetooth") != NULL
1433 #endif
1434 #ifdef PCAP_SUPPORT_USB
1435 	    || strstr(device, "usbmon") != NULL
1436 #endif
1437 #ifdef HAVE_SNF_API
1438 	    || strstr(device, "snf") != NULL
1439 #endif
1440 #ifdef PCAP_SUPPORT_NETMAP
1441 	    || strncmp(device, "netmap:", 7) == 0
1442 	    || strncmp(device, "vale", 4) == 0
1443 #endif
1444 	    ) {
1445 		*netp = *maskp = 0;
1446 		return 0;
1447 	}
1448 
1449 	fd = socket(AF_INET, SOCK_DGRAM, 0);
1450 	if (fd < 0) {
1451 		pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
1452 		    errno, "socket");
1453 		return (-1);
1454 	}
1455 	memset(&ifr, 0, sizeof(ifr));
1456 #ifdef linux
1457 	/* XXX Work around Linux kernel bug */
1458 	ifr.ifr_addr.sa_family = AF_INET;
1459 #endif
1460 	(void)pcap_strlcpy(ifr.ifr_name, device, sizeof(ifr.ifr_name));
1461 	if (ioctl(fd, SIOCGIFADDR, (char *)&ifr) < 0) {
1462 		if (errno == EADDRNOTAVAIL) {
1463 			(void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
1464 			    "%s: no IPv4 address assigned", device);
1465 		} else {
1466 			pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
1467 			    errno, "SIOCGIFADDR: %s", device);
1468 		}
1469 		(void)close(fd);
1470 		return (-1);
1471 	}
1472 	sin4 = (struct sockaddr_in *)&ifr.ifr_addr;
1473 	*netp = sin4->sin_addr.s_addr;
1474 	memset(&ifr, 0, sizeof(ifr));
1475 #ifdef linux
1476 	/* XXX Work around Linux kernel bug */
1477 	ifr.ifr_addr.sa_family = AF_INET;
1478 #endif
1479 	(void)pcap_strlcpy(ifr.ifr_name, device, sizeof(ifr.ifr_name));
1480 	if (ioctl(fd, SIOCGIFNETMASK, (char *)&ifr) < 0) {
1481 		pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
1482 		    errno, "SIOCGIFNETMASK: %s", device);
1483 		(void)close(fd);
1484 		return (-1);
1485 	}
1486 	(void)close(fd);
1487 	*maskp = sin4->sin_addr.s_addr;
1488 	if (*maskp == 0) {
1489 		if (IN_CLASSA(*netp))
1490 			*maskp = IN_CLASSA_NET;
1491 		else if (IN_CLASSB(*netp))
1492 			*maskp = IN_CLASSB_NET;
1493 		else if (IN_CLASSC(*netp))
1494 			*maskp = IN_CLASSC_NET;
1495 		else {
1496 			(void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
1497 			    "inet class for 0x%x unknown", *netp);
1498 			return (-1);
1499 		}
1500 	}
1501 	*netp &= *maskp;
1502 	return (0);
1503 }
1504 #endif /* !defined(_WIN32) && !defined(MSDOS) */
1505 
1506 #ifdef ENABLE_REMOTE
1507 #include "pcap-rpcap.h"
1508 
1509 /*
1510  * Extract a substring from a string.
1511  */
1512 static char *
1513 get_substring(const char *p, size_t len, char *ebuf)
1514 {
1515 	char *token;
1516 
1517 	token = malloc(len + 1);
1518 	if (token == NULL) {
1519 		pcap_fmt_errmsg_for_errno(ebuf, PCAP_ERRBUF_SIZE,
1520 		    errno, "malloc");
1521 		return (NULL);
1522 	}
1523 	memcpy(token, p, len);
1524 	token[len] = '\0';
1525 	return (token);
1526 }
1527 
1528 /*
1529  * Parse a capture source that might be a URL.
1530  *
1531  * If the source is not a URL, *schemep, *userinfop, *hostp, and *portp
1532  * are set to NULL, *pathp is set to point to the source, and 0 is
1533  * returned.
1534  *
1535  * If source is a URL, and the URL refers to a local device (a special
1536  * case of rpcap:), *schemep, *userinfop, *hostp, and *portp are set
1537  * to NULL, *pathp is set to point to the device name, and 0 is returned.
1538  *
1539  * If source is a URL, and it's not a special case that refers to a local
1540  * device, and the parse succeeds:
1541  *
1542  *    *schemep is set to point to an allocated string containing the scheme;
1543  *
1544  *    if user information is present in the URL, *userinfop is set to point
1545  *    to an allocated string containing the user information, otherwise
1546  *    it's set to NULL;
1547  *
1548  *    if host information is present in the URL, *hostp is set to point
1549  *    to an allocated string containing the host information, otherwise
1550  *    it's set to NULL;
1551  *
1552  *    if a port number is present in the URL, *portp is set to point
1553  *    to an allocated string containing the port number, otherwise
1554  *    it's set to NULL;
1555  *
1556  *    *pathp is set to point to an allocated string containing the
1557  *    path;
1558  *
1559  * and 0 is returned.
1560  *
1561  * If the parse fails, ebuf is set to an error string, and -1 is returned.
1562  */
1563 static int
1564 pcap_parse_source(const char *source, char **schemep, char **userinfop,
1565     char **hostp, char **portp, char **pathp, char *ebuf)
1566 {
1567 	char *colonp;
1568 	size_t scheme_len;
1569 	char *scheme;
1570 	const char *endp;
1571 	size_t authority_len;
1572 	char *authority;
1573 	char *parsep, *atsignp, *bracketp;
1574 	char *userinfo, *host, *port, *path;
1575 
1576 	/*
1577 	 * Start out returning nothing.
1578 	 */
1579 	*schemep = NULL;
1580 	*userinfop = NULL;
1581 	*hostp = NULL;
1582 	*portp = NULL;
1583 	*pathp = NULL;
1584 
1585 	/*
1586 	 * RFC 3986 says:
1587 	 *
1588 	 *   URI         = scheme ":" hier-part [ "?" query ] [ "#" fragment ]
1589 	 *
1590 	 *   hier-part   = "//" authority path-abempty
1591 	 *               / path-absolute
1592 	 *               / path-rootless
1593 	 *               / path-empty
1594 	 *
1595 	 *   authority   = [ userinfo "@" ] host [ ":" port ]
1596 	 *
1597 	 *   userinfo    = *( unreserved / pct-encoded / sub-delims / ":" )
1598          *
1599          * Step 1: look for the ":" at the end of the scheme.
1600 	 * A colon in the source is *NOT* sufficient to indicate that
1601 	 * this is a URL, as interface names on some platforms might
1602 	 * include colons (e.g., I think some Solaris interfaces
1603 	 * might).
1604 	 */
1605 	colonp = strchr(source, ':');
1606 	if (colonp == NULL) {
1607 		/*
1608 		 * The source is the device to open.
1609 		 * Return a NULL pointer for the scheme, user information,
1610 		 * host, and port, and return the device as the path.
1611 		 */
1612 		*pathp = strdup(source);
1613 		if (*pathp == NULL) {
1614 			pcap_fmt_errmsg_for_errno(ebuf, PCAP_ERRBUF_SIZE,
1615 			    errno, "malloc");
1616 			return (-1);
1617 		}
1618 		return (0);
1619 	}
1620 
1621 	/*
1622 	 * All schemes must have "//" after them, i.e. we only support
1623 	 * hier-part   = "//" authority path-abempty, not
1624 	 * hier-part   = path-absolute
1625 	 * hier-part   = path-rootless
1626 	 * hier-part   = path-empty
1627 	 *
1628 	 * We need that in order to distinguish between a local device
1629 	 * name that happens to contain a colon and a URI.
1630 	 */
1631 	if (strncmp(colonp + 1, "//", 2) != 0) {
1632 		/*
1633 		 * The source is the device to open.
1634 		 * Return a NULL pointer for the scheme, user information,
1635 		 * host, and port, and return the device as the path.
1636 		 */
1637 		*pathp = strdup(source);
1638 		if (*pathp == NULL) {
1639 			pcap_fmt_errmsg_for_errno(ebuf, PCAP_ERRBUF_SIZE,
1640 			    errno, "malloc");
1641 			return (-1);
1642 		}
1643 		return (0);
1644 	}
1645 
1646 	/*
1647 	 * XXX - check whether the purported scheme could be a scheme?
1648 	 */
1649 
1650 	/*
1651 	 * OK, this looks like a URL.
1652 	 * Get the scheme.
1653 	 */
1654 	scheme_len = colonp - source;
1655 	scheme = malloc(scheme_len + 1);
1656 	if (scheme == NULL) {
1657 		pcap_fmt_errmsg_for_errno(ebuf, PCAP_ERRBUF_SIZE,
1658 		    errno, "malloc");
1659 		return (-1);
1660 	}
1661 	memcpy(scheme, source, scheme_len);
1662 	scheme[scheme_len] = '\0';
1663 
1664 	/*
1665 	 * Treat file: specially - take everything after file:// as
1666 	 * the pathname.
1667 	 */
1668 	if (pcap_strcasecmp(scheme, "file") == 0) {
1669 		*pathp = strdup(colonp + 3);
1670 		if (*pathp == NULL) {
1671 			pcap_fmt_errmsg_for_errno(ebuf, PCAP_ERRBUF_SIZE,
1672 			    errno, "malloc");
1673 			free(scheme);
1674 			return (-1);
1675 		}
1676 		*schemep = scheme;
1677 		return (0);
1678 	}
1679 
1680 	/*
1681 	 * The WinPcap documentation says you can specify a local
1682 	 * interface with "rpcap://{device}"; we special-case
1683 	 * that here.  If the scheme is "rpcap", and there are
1684 	 * no slashes past the "//", we just return the device.
1685 	 *
1686 	 * XXX - %-escaping?
1687 	 */
1688 	if (pcap_strcasecmp(scheme, "rpcap") == 0 &&
1689 	    strchr(colonp + 3, '/') == NULL) {
1690 		/*
1691 		 * Local device.
1692 		 *
1693 		 * Return a NULL pointer for the scheme, user information,
1694 		 * host, and port, and return the device as the path.
1695 		 */
1696 		free(scheme);
1697 		*pathp = strdup(colonp + 3);
1698 		if (*pathp == NULL) {
1699 			pcap_fmt_errmsg_for_errno(ebuf, PCAP_ERRBUF_SIZE,
1700 			    errno, "malloc");
1701 			return (-1);
1702 		}
1703 		return (0);
1704 	}
1705 
1706 	/*
1707 	 * OK, now start parsing the authority.
1708 	 * Get token, terminated with / or terminated at the end of
1709 	 * the string.
1710 	 */
1711 	authority_len = strcspn(colonp + 3, "/");
1712 	authority = get_substring(colonp + 3, authority_len, ebuf);
1713 	if (authority == NULL) {
1714 		/*
1715 		 * Error.
1716 		 */
1717 		free(scheme);
1718 		return (-1);
1719 	}
1720 	endp = colonp + 3 + authority_len;
1721 
1722 	/*
1723 	 * Now carve the authority field into its components.
1724 	 */
1725 	parsep = authority;
1726 
1727 	/*
1728 	 * Is there a userinfo field?
1729 	 */
1730 	atsignp = strchr(parsep, '@');
1731 	if (atsignp != NULL) {
1732 		/*
1733 		 * Yes.
1734 		 */
1735 		size_t userinfo_len;
1736 
1737 		userinfo_len = atsignp - parsep;
1738 		userinfo = get_substring(parsep, userinfo_len, ebuf);
1739 		if (userinfo == NULL) {
1740 			/*
1741 			 * Error.
1742 			 */
1743 			free(authority);
1744 			free(scheme);
1745 			return (-1);
1746 		}
1747 		parsep = atsignp + 1;
1748 	} else {
1749 		/*
1750 		 * No.
1751 		 */
1752 		userinfo = NULL;
1753 	}
1754 
1755 	/*
1756 	 * Is there a host field?
1757 	 */
1758 	if (*parsep == '\0') {
1759 		/*
1760 		 * No; there's no host field or port field.
1761 		 */
1762 		host = NULL;
1763 		port = NULL;
1764 	} else {
1765 		/*
1766 		 * Yes.
1767 		 */
1768 		size_t host_len;
1769 
1770 		/*
1771 		 * Is it an IP-literal?
1772 		 */
1773 		if (*parsep == '[') {
1774 			/*
1775 			 * Yes.
1776 			 * Treat verything up to the closing square
1777 			 * bracket as the IP-Literal; we don't worry
1778 			 * about whether it's a valid IPv6address or
1779 			 * IPvFuture (or an IPv4address, for that
1780 			 * matter, just in case we get handed a
1781 			 * URL with an IPv4 IP-Literal, of the sort
1782 			 * that pcap_createsrcstr() used to generate,
1783 			 * and that pcap_parsesrcstr(), in the original
1784 			 * WinPcap code, accepted).
1785 			 */
1786 			bracketp = strchr(parsep, ']');
1787 			if (bracketp == NULL) {
1788 				/*
1789 				 * There's no closing square bracket.
1790 				 */
1791 				pcap_snprintf(ebuf, PCAP_ERRBUF_SIZE,
1792 				    "IP-literal in URL doesn't end with ]");
1793 				free(userinfo);
1794 				free(authority);
1795 				free(scheme);
1796 				return (-1);
1797 			}
1798 			if (*(bracketp + 1) != '\0' &&
1799 			    *(bracketp + 1) != ':') {
1800 				/*
1801 				 * There's extra crud after the
1802 				 * closing square bracketn.
1803 				 */
1804 				pcap_snprintf(ebuf, PCAP_ERRBUF_SIZE,
1805 				    "Extra text after IP-literal in URL");
1806 				free(userinfo);
1807 				free(authority);
1808 				free(scheme);
1809 				return (-1);
1810 			}
1811 			host_len = (bracketp - 1) - parsep;
1812 			host = get_substring(parsep + 1, host_len, ebuf);
1813 			if (host == NULL) {
1814 				/*
1815 				 * Error.
1816 				 */
1817 				free(userinfo);
1818 				free(authority);
1819 				free(scheme);
1820 				return (-1);
1821 			}
1822 			parsep = bracketp + 1;
1823 		} else {
1824 			/*
1825 			 * No.
1826 			 * Treat everything up to a : or the end of
1827 			 * the string as the host.
1828 			 */
1829 			host_len = strcspn(parsep, ":");
1830 			host = get_substring(parsep, host_len, ebuf);
1831 			if (host == NULL) {
1832 				/*
1833 				 * Error.
1834 				 */
1835 				free(userinfo);
1836 				free(authority);
1837 				free(scheme);
1838 				return (-1);
1839 			}
1840 			parsep = parsep + host_len;
1841 		}
1842 
1843 		/*
1844 		 * Is there a port field?
1845 		 */
1846 		if (*parsep == ':') {
1847 			/*
1848 			 * Yes.  It's the rest of the authority field.
1849 			 */
1850 			size_t port_len;
1851 
1852 			parsep++;
1853 			port_len = strlen(parsep);
1854 			port = get_substring(parsep, port_len, ebuf);
1855 			if (port == NULL) {
1856 				/*
1857 				 * Error.
1858 				 */
1859 				free(host);
1860 				free(userinfo);
1861 				free(authority);
1862 				free(scheme);
1863 				return (-1);
1864 			}
1865 		} else {
1866 			/*
1867 			 * No.
1868 			 */
1869 			port = NULL;
1870 		}
1871 	}
1872 	free(authority);
1873 
1874 	/*
1875 	 * Everything else is the path.  Strip off the leading /.
1876 	 */
1877 	if (*endp == '\0')
1878 		path = strdup("");
1879 	else
1880 		path = strdup(endp + 1);
1881 	if (path == NULL) {
1882 		pcap_fmt_errmsg_for_errno(ebuf, PCAP_ERRBUF_SIZE,
1883 		    errno, "malloc");
1884 		free(port);
1885 		free(host);
1886 		free(userinfo);
1887 		free(scheme);
1888 		return (-1);
1889 	}
1890 	*schemep = scheme;
1891 	*userinfop = userinfo;
1892 	*hostp = host;
1893 	*portp = port;
1894 	*pathp = path;
1895 	return (0);
1896 }
1897 
1898 int
1899 pcap_createsrcstr(char *source, int type, const char *host, const char *port,
1900     const char *name, char *errbuf)
1901 {
1902 	switch (type) {
1903 
1904 	case PCAP_SRC_FILE:
1905 		pcap_strlcpy(source, PCAP_SRC_FILE_STRING, PCAP_BUF_SIZE);
1906 		if (name != NULL && *name != '\0') {
1907 			pcap_strlcat(source, name, PCAP_BUF_SIZE);
1908 			return (0);
1909 		} else {
1910 			pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
1911 			    "The file name cannot be NULL.");
1912 			return (-1);
1913 		}
1914 
1915 	case PCAP_SRC_IFREMOTE:
1916 		pcap_strlcpy(source, PCAP_SRC_IF_STRING, PCAP_BUF_SIZE);
1917 		if (host != NULL && *host != '\0') {
1918 			if (strchr(host, ':') != NULL) {
1919 				/*
1920 				 * The host name contains a colon, so it's
1921 				 * probably an IPv6 address, and needs to
1922 				 * be included in square brackets.
1923 				 */
1924 				pcap_strlcat(source, "[", PCAP_BUF_SIZE);
1925 				pcap_strlcat(source, host, PCAP_BUF_SIZE);
1926 				pcap_strlcat(source, "]", PCAP_BUF_SIZE);
1927 			} else
1928 				pcap_strlcat(source, host, PCAP_BUF_SIZE);
1929 
1930 			if (port != NULL && *port != '\0') {
1931 				pcap_strlcat(source, ":", PCAP_BUF_SIZE);
1932 				pcap_strlcat(source, port, PCAP_BUF_SIZE);
1933 			}
1934 
1935 			pcap_strlcat(source, "/", PCAP_BUF_SIZE);
1936 		} else {
1937 			pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
1938 			    "The host name cannot be NULL.");
1939 			return (-1);
1940 		}
1941 
1942 		if (name != NULL && *name != '\0')
1943 			pcap_strlcat(source, name, PCAP_BUF_SIZE);
1944 
1945 		return (0);
1946 
1947 	case PCAP_SRC_IFLOCAL:
1948 		pcap_strlcpy(source, PCAP_SRC_IF_STRING, PCAP_BUF_SIZE);
1949 
1950 		if (name != NULL && *name != '\0')
1951 			pcap_strlcat(source, name, PCAP_BUF_SIZE);
1952 
1953 		return (0);
1954 
1955 	default:
1956 		pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
1957 		    "The interface type is not valid.");
1958 		return (-1);
1959 	}
1960 }
1961 
1962 int
1963 pcap_parsesrcstr(const char *source, int *type, char *host, char *port,
1964     char *name, char *errbuf)
1965 {
1966 	char *scheme, *tmpuserinfo, *tmphost, *tmpport, *tmppath;
1967 
1968 	/* Initialization stuff */
1969 	if (host)
1970 		*host = '\0';
1971 	if (port)
1972 		*port = '\0';
1973 	if (name)
1974 		*name = '\0';
1975 
1976 	/* Parse the source string */
1977 	if (pcap_parse_source(source, &scheme, &tmpuserinfo, &tmphost,
1978 	    &tmpport, &tmppath, errbuf) == -1) {
1979 		/*
1980 		 * Fail.
1981 		 */
1982 		return (-1);
1983 	}
1984 
1985 	if (scheme == NULL) {
1986 		/*
1987 		 * Local device.
1988 		 */
1989 		if (name && tmppath)
1990 			pcap_strlcpy(name, tmppath, PCAP_BUF_SIZE);
1991 		if (type)
1992 			*type = PCAP_SRC_IFLOCAL;
1993 		free(tmppath);
1994 		free(tmpport);
1995 		free(tmphost);
1996 		free(tmpuserinfo);
1997 		return (0);
1998 	}
1999 
2000 	if (strcmp(scheme, "rpcap") == 0) {
2001 		/*
2002 		 * rpcap://
2003 		 *
2004 		 * pcap_parse_source() has already handled the case of
2005 		 * rpcap://device
2006 		 */
2007 		if (host && tmphost) {
2008 			if (tmpuserinfo)
2009 				pcap_snprintf(host, PCAP_BUF_SIZE, "%s@%s",
2010 				    tmpuserinfo, tmphost);
2011 			else
2012 				pcap_strlcpy(host, tmphost, PCAP_BUF_SIZE);
2013 		}
2014 		if (port && tmpport)
2015 			pcap_strlcpy(port, tmpport, PCAP_BUF_SIZE);
2016 		if (name && tmppath)
2017 			pcap_strlcpy(name, tmppath, PCAP_BUF_SIZE);
2018 		if (type)
2019 			*type = PCAP_SRC_IFREMOTE;
2020 		free(tmppath);
2021 		free(tmpport);
2022 		free(tmphost);
2023 		free(tmpuserinfo);
2024 		free(scheme);
2025 		return (0);
2026 	}
2027 
2028 	if (strcmp(scheme, "file") == 0) {
2029 		/*
2030 		 * file://
2031 		 */
2032 		if (name && tmppath)
2033 			pcap_strlcpy(name, tmppath, PCAP_BUF_SIZE);
2034 		if (type)
2035 			*type = PCAP_SRC_FILE;
2036 		free(tmppath);
2037 		free(tmpport);
2038 		free(tmphost);
2039 		free(tmpuserinfo);
2040 		free(scheme);
2041 		return (0);
2042 	}
2043 
2044 	/*
2045 	 * Neither rpcap: nor file:; just treat the entire string
2046 	 * as a local device.
2047 	 */
2048 	if (name)
2049 		pcap_strlcpy(name, source, PCAP_BUF_SIZE);
2050 	if (type)
2051 		*type = PCAP_SRC_IFLOCAL;
2052 	free(tmppath);
2053 	free(tmpport);
2054 	free(tmphost);
2055 	free(tmpuserinfo);
2056 	free(scheme);
2057 	return (0);
2058 }
2059 #endif
2060 
2061 pcap_t *
2062 pcap_create(const char *device, char *errbuf)
2063 {
2064 	size_t i;
2065 	int is_theirs;
2066 	pcap_t *p;
2067 	char *device_str;
2068 
2069 	/*
2070 	 * A null device name is equivalent to the "any" device -
2071 	 * which might not be supported on this platform, but
2072 	 * this means that you'll get a "not supported" error
2073 	 * rather than, say, a crash when we try to dereference
2074 	 * the null pointer.
2075 	 */
2076 	if (device == NULL)
2077 		device_str = strdup("any");
2078 	else {
2079 #ifdef _WIN32
2080 		/*
2081 		 * On Windows, for backwards compatibility reasons,
2082 		 * pcap_lookupdev() returns a pointer to a sequence of
2083 		 * pairs of UTF-16LE device names and local code page
2084 		 * description strings.
2085 		 *
2086 		 * This means that if a program uses pcap_lookupdev()
2087 		 * to get a default device, and hands that to an API
2088 		 * that opens devices, we'll get handed a UTF-16LE
2089 		 * string, not a string in the local code page.
2090 		 *
2091 		 * To work around that, we check whether the string
2092 		 * looks as if it might be a UTF-16LE strinh and, if
2093 		 * so, convert it back to the local code page's
2094 		 * extended ASCII.
2095 		 *
2096 		 * XXX - you *cannot* reliably detect whether a
2097 		 * string is UTF-16LE or not; "a" could either
2098 		 * be a one-character ASCII string or the first
2099 		 * character of a UTF-16LE string.  This particular
2100 		 * version of this heuristic dates back to WinPcap
2101 		 * 4.1.1; PacketOpenAdapter() does uses the same
2102 		 * heuristic, with the exact same vulnerability.
2103 		 */
2104 		if (device[0] != '\0' && device[1] == '\0') {
2105 			size_t length;
2106 
2107 			length = wcslen((wchar_t *)device);
2108 			device_str = (char *)malloc(length + 1);
2109 			if (device_str == NULL) {
2110 				pcap_fmt_errmsg_for_errno(errbuf,
2111 				    PCAP_ERRBUF_SIZE, errno,
2112 				    "malloc");
2113 				return (NULL);
2114 			}
2115 
2116 			pcap_snprintf(device_str, length + 1, "%ws",
2117 			    (const wchar_t *)device);
2118 		} else
2119 #endif
2120 			device_str = strdup(device);
2121 	}
2122 	if (device_str == NULL) {
2123 		pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
2124 		    errno, "malloc");
2125 		return (NULL);
2126 	}
2127 
2128 	/*
2129 	 * Try each of the non-local-network-interface capture
2130 	 * source types until we find one that works for this
2131 	 * device or run out of types.
2132 	 */
2133 	for (i = 0; capture_source_types[i].create_op != NULL; i++) {
2134 		is_theirs = 0;
2135 		p = capture_source_types[i].create_op(device_str, errbuf,
2136 		    &is_theirs);
2137 		if (is_theirs) {
2138 			/*
2139 			 * The device name refers to a device of the
2140 			 * type in question; either it succeeded,
2141 			 * in which case p refers to a pcap_t to
2142 			 * later activate for the device, or it
2143 			 * failed, in which case p is null and we
2144 			 * should return that to report the failure
2145 			 * to create.
2146 			 */
2147 			if (p == NULL) {
2148 				/*
2149 				 * We assume the caller filled in errbuf.
2150 				 */
2151 				free(device_str);
2152 				return (NULL);
2153 			}
2154 			p->opt.device = device_str;
2155 			return (p);
2156 		}
2157 	}
2158 
2159 	/*
2160 	 * OK, try it as a regular network interface.
2161 	 */
2162 	p = pcap_create_interface(device_str, errbuf);
2163 	if (p == NULL) {
2164 		/*
2165 		 * We assume the caller filled in errbuf.
2166 		 */
2167 		free(device_str);
2168 		return (NULL);
2169 	}
2170 	p->opt.device = device_str;
2171 	return (p);
2172 }
2173 
2174 /*
2175  * Set nonblocking mode on an unactivated pcap_t; this sets a flag
2176  * checked by pcap_activate(), which sets the mode after calling
2177  * the activate routine.
2178  */
2179 static int
2180 pcap_setnonblock_unactivated(pcap_t *p, int nonblock)
2181 {
2182 	p->opt.nonblock = nonblock;
2183 	return (0);
2184 }
2185 
2186 static void
2187 initialize_ops(pcap_t *p)
2188 {
2189 	/*
2190 	 * Set operation pointers for operations that only work on
2191 	 * an activated pcap_t to point to a routine that returns
2192 	 * a "this isn't activated" error.
2193 	 */
2194 	p->read_op = pcap_read_not_initialized;
2195 	p->inject_op = pcap_inject_not_initialized;
2196 	p->setfilter_op = pcap_setfilter_not_initialized;
2197 	p->setdirection_op = pcap_setdirection_not_initialized;
2198 	p->set_datalink_op = pcap_set_datalink_not_initialized;
2199 	p->getnonblock_op = pcap_getnonblock_not_initialized;
2200 	p->stats_op = pcap_stats_not_initialized;
2201 #ifdef _WIN32
2202 	p->stats_ex_op = pcap_stats_ex_not_initialized;
2203 	p->setbuff_op = pcap_setbuff_not_initialized;
2204 	p->setmode_op = pcap_setmode_not_initialized;
2205 	p->setmintocopy_op = pcap_setmintocopy_not_initialized;
2206 	p->getevent_op = pcap_getevent_not_initialized;
2207 	p->oid_get_request_op = pcap_oid_get_request_not_initialized;
2208 	p->oid_set_request_op = pcap_oid_set_request_not_initialized;
2209 	p->sendqueue_transmit_op = pcap_sendqueue_transmit_not_initialized;
2210 	p->setuserbuffer_op = pcap_setuserbuffer_not_initialized;
2211 	p->live_dump_op = pcap_live_dump_not_initialized;
2212 	p->live_dump_ended_op = pcap_live_dump_ended_not_initialized;
2213 	p->get_airpcap_handle_op = pcap_get_airpcap_handle_not_initialized;
2214 #endif
2215 
2216 	/*
2217 	 * Default cleanup operation - implementations can override
2218 	 * this, but should call pcap_cleanup_live_common() after
2219 	 * doing their own additional cleanup.
2220 	 */
2221 	p->cleanup_op = pcap_cleanup_live_common;
2222 
2223 	/*
2224 	 * In most cases, the standard one-shot callback can
2225 	 * be used for pcap_next()/pcap_next_ex().
2226 	 */
2227 	p->oneshot_callback = pcap_oneshot;
2228 }
2229 
2230 static pcap_t *
2231 pcap_alloc_pcap_t(char *ebuf, size_t size)
2232 {
2233 	char *chunk;
2234 	pcap_t *p;
2235 
2236 	/*
2237 	 * Allocate a chunk of memory big enough for a pcap_t
2238 	 * plus a structure following it of size "size".  The
2239 	 * structure following it is a private data structure
2240 	 * for the routines that handle this pcap_t.
2241 	 *
2242 	 * The structure following it must be aligned on
2243 	 * the appropriate alignment boundary for this platform.
2244 	 * We align on an 8-byte boundary as that's probably what
2245 	 * at least some platforms do, even with 32-bit integers,
2246 	 * and because we can't be sure that some values won't
2247 	 * require 8-byte alignment even on platforms with 32-bit
2248 	 * integers.
2249 	 */
2250 #define PCAP_T_ALIGNED_SIZE	((sizeof(pcap_t) + 7U) & ~0x7U)
2251 	chunk = malloc(PCAP_T_ALIGNED_SIZE + size);
2252 	if (chunk == NULL) {
2253 		pcap_fmt_errmsg_for_errno(ebuf, PCAP_ERRBUF_SIZE,
2254 		    errno, "malloc");
2255 		return (NULL);
2256 	}
2257 	memset(chunk, 0, PCAP_T_ALIGNED_SIZE + size);
2258 
2259 	/*
2260 	 * Get a pointer to the pcap_t at the beginning.
2261 	 */
2262 	p = (pcap_t *)chunk;
2263 
2264 #ifdef _WIN32
2265 	p->handle = INVALID_HANDLE_VALUE;	/* not opened yet */
2266 #else /* _WIN32 */
2267 	p->fd = -1;	/* not opened yet */
2268 #ifndef MSDOS
2269 	p->selectable_fd = -1;
2270 	p->required_select_timeout = NULL;
2271 #endif /* MSDOS */
2272 #endif /* _WIN32 */
2273 
2274 	if (size == 0) {
2275 		/* No private data was requested. */
2276 		p->priv = NULL;
2277 	} else {
2278 		/*
2279 		 * Set the pointer to the private data; that's the structure
2280 		 * of size "size" following the pcap_t.
2281 		 */
2282 		p->priv = (void *)(chunk + PCAP_T_ALIGNED_SIZE);
2283 	}
2284 
2285 	return (p);
2286 }
2287 
2288 pcap_t *
2289 pcap_create_common(char *ebuf, size_t size)
2290 {
2291 	pcap_t *p;
2292 
2293 	p = pcap_alloc_pcap_t(ebuf, size);
2294 	if (p == NULL)
2295 		return (NULL);
2296 
2297 	/*
2298 	 * Default to "can't set rfmon mode"; if it's supported by
2299 	 * a platform, the create routine that called us can set
2300 	 * the op to its routine to check whether a particular
2301 	 * device supports it.
2302 	 */
2303 	p->can_set_rfmon_op = pcap_cant_set_rfmon;
2304 
2305 	/*
2306 	 * If pcap_setnonblock() is called on a not-yet-activated
2307 	 * pcap_t, default to setting a flag and turning
2308 	 * on non-blocking mode when activated.
2309 	 */
2310 	p->setnonblock_op = pcap_setnonblock_unactivated;
2311 
2312 	initialize_ops(p);
2313 
2314 	/* put in some defaults*/
2315 	p->snapshot = 0;		/* max packet size unspecified */
2316 	p->opt.timeout = 0;		/* no timeout specified */
2317 	p->opt.buffer_size = 0;		/* use the platform's default */
2318 	p->opt.promisc = 0;
2319 	p->opt.rfmon = 0;
2320 	p->opt.immediate = 0;
2321 	p->opt.tstamp_type = -1;	/* default to not setting time stamp type */
2322 	p->opt.tstamp_precision = PCAP_TSTAMP_PRECISION_MICRO;
2323 	/*
2324 	 * Platform-dependent options.
2325 	 */
2326 #ifdef __linux__
2327 	p->opt.protocol = 0;
2328 #endif
2329 #ifdef _WIN32
2330 	p->opt.nocapture_local = 0;
2331 #endif
2332 
2333 	/*
2334 	 * Start out with no BPF code generation flags set.
2335 	 */
2336 	p->bpf_codegen_flags = 0;
2337 
2338 	return (p);
2339 }
2340 
2341 int
2342 pcap_check_activated(pcap_t *p)
2343 {
2344 	if (p->activated) {
2345 		pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "can't perform "
2346 			" operation on activated capture");
2347 		return (-1);
2348 	}
2349 	return (0);
2350 }
2351 
2352 int
2353 pcap_set_snaplen(pcap_t *p, int snaplen)
2354 {
2355 	if (pcap_check_activated(p))
2356 		return (PCAP_ERROR_ACTIVATED);
2357 	p->snapshot = snaplen;
2358 	return (0);
2359 }
2360 
2361 int
2362 pcap_set_promisc(pcap_t *p, int promisc)
2363 {
2364 	if (pcap_check_activated(p))
2365 		return (PCAP_ERROR_ACTIVATED);
2366 	p->opt.promisc = promisc;
2367 	return (0);
2368 }
2369 
2370 int
2371 pcap_set_rfmon(pcap_t *p, int rfmon)
2372 {
2373 	if (pcap_check_activated(p))
2374 		return (PCAP_ERROR_ACTIVATED);
2375 	p->opt.rfmon = rfmon;
2376 	return (0);
2377 }
2378 
2379 int
2380 pcap_set_timeout(pcap_t *p, int timeout_ms)
2381 {
2382 	if (pcap_check_activated(p))
2383 		return (PCAP_ERROR_ACTIVATED);
2384 	p->opt.timeout = timeout_ms;
2385 	return (0);
2386 }
2387 
2388 int
2389 pcap_set_tstamp_type(pcap_t *p, int tstamp_type)
2390 {
2391 	int i;
2392 
2393 	if (pcap_check_activated(p))
2394 		return (PCAP_ERROR_ACTIVATED);
2395 
2396 	/*
2397 	 * The argument should have been u_int, but that's too late
2398 	 * to change now - it's an API.
2399 	 */
2400 	if (tstamp_type < 0)
2401 		return (PCAP_WARNING_TSTAMP_TYPE_NOTSUP);
2402 
2403 	/*
2404 	 * If p->tstamp_type_count is 0, we only support PCAP_TSTAMP_HOST;
2405 	 * the default time stamp type is PCAP_TSTAMP_HOST.
2406 	 */
2407 	if (p->tstamp_type_count == 0) {
2408 		if (tstamp_type == PCAP_TSTAMP_HOST) {
2409 			p->opt.tstamp_type = tstamp_type;
2410 			return (0);
2411 		}
2412 	} else {
2413 		/*
2414 		 * Check whether we claim to support this type of time stamp.
2415 		 */
2416 		for (i = 0; i < p->tstamp_type_count; i++) {
2417 			if (p->tstamp_type_list[i] == (u_int)tstamp_type) {
2418 				/*
2419 				 * Yes.
2420 				 */
2421 				p->opt.tstamp_type = tstamp_type;
2422 				return (0);
2423 			}
2424 		}
2425 	}
2426 
2427 	/*
2428 	 * We don't support this type of time stamp.
2429 	 */
2430 	return (PCAP_WARNING_TSTAMP_TYPE_NOTSUP);
2431 }
2432 
2433 int
2434 pcap_set_immediate_mode(pcap_t *p, int immediate)
2435 {
2436 	if (pcap_check_activated(p))
2437 		return (PCAP_ERROR_ACTIVATED);
2438 	p->opt.immediate = immediate;
2439 	return (0);
2440 }
2441 
2442 int
2443 pcap_set_buffer_size(pcap_t *p, int buffer_size)
2444 {
2445 	if (pcap_check_activated(p))
2446 		return (PCAP_ERROR_ACTIVATED);
2447 	if (buffer_size <= 0) {
2448 		/*
2449 		 * Silently ignore invalid values.
2450 		 */
2451 		return (0);
2452 	}
2453 	p->opt.buffer_size = buffer_size;
2454 	return (0);
2455 }
2456 
2457 int
2458 pcap_set_tstamp_precision(pcap_t *p, int tstamp_precision)
2459 {
2460 	int i;
2461 
2462 	if (pcap_check_activated(p))
2463 		return (PCAP_ERROR_ACTIVATED);
2464 
2465 	/*
2466 	 * The argument should have been u_int, but that's too late
2467 	 * to change now - it's an API.
2468 	 */
2469 	if (tstamp_precision < 0)
2470 		return (PCAP_ERROR_TSTAMP_PRECISION_NOTSUP);
2471 
2472 	/*
2473 	 * If p->tstamp_precision_count is 0, we only support setting
2474 	 * the time stamp precision to microsecond precision; every
2475 	 * pcap module *MUST* support microsecond precision, even if
2476 	 * it does so by converting the native precision to
2477 	 * microseconds.
2478 	 */
2479 	if (p->tstamp_precision_count == 0) {
2480 		if (tstamp_precision == PCAP_TSTAMP_PRECISION_MICRO) {
2481 			p->opt.tstamp_precision = tstamp_precision;
2482 			return (0);
2483 		}
2484 	} else {
2485 		/*
2486 		 * Check whether we claim to support this precision of
2487 		 * time stamp.
2488 		 */
2489 		for (i = 0; i < p->tstamp_precision_count; i++) {
2490 			if (p->tstamp_precision_list[i] == (u_int)tstamp_precision) {
2491 				/*
2492 				 * Yes.
2493 				 */
2494 				p->opt.tstamp_precision = tstamp_precision;
2495 				return (0);
2496 			}
2497 		}
2498 	}
2499 
2500 	/*
2501 	 * We don't support this time stamp precision.
2502 	 */
2503 	return (PCAP_ERROR_TSTAMP_PRECISION_NOTSUP);
2504 }
2505 
2506 int
2507 pcap_get_tstamp_precision(pcap_t *p)
2508 {
2509         return (p->opt.tstamp_precision);
2510 }
2511 
2512 int
2513 pcap_activate(pcap_t *p)
2514 {
2515 	int status;
2516 
2517 	/*
2518 	 * Catch attempts to re-activate an already-activated
2519 	 * pcap_t; this should, for example, catch code that
2520 	 * calls pcap_open_live() followed by pcap_activate(),
2521 	 * as some code that showed up in a Stack Exchange
2522 	 * question did.
2523 	 */
2524 	if (pcap_check_activated(p))
2525 		return (PCAP_ERROR_ACTIVATED);
2526 	status = p->activate_op(p);
2527 	if (status >= 0) {
2528 		/*
2529 		 * If somebody requested non-blocking mode before
2530 		 * calling pcap_activate(), turn it on now.
2531 		 */
2532 		if (p->opt.nonblock) {
2533 			status = p->setnonblock_op(p, 1);
2534 			if (status < 0) {
2535 				/*
2536 				 * Failed.  Undo everything done by
2537 				 * the activate operation.
2538 				 */
2539 				p->cleanup_op(p);
2540 				initialize_ops(p);
2541 				return (status);
2542 			}
2543 		}
2544 		p->activated = 1;
2545 	} else {
2546 		if (p->errbuf[0] == '\0') {
2547 			/*
2548 			 * No error message supplied by the activate routine;
2549 			 * for the benefit of programs that don't specially
2550 			 * handle errors other than PCAP_ERROR, return the
2551 			 * error message corresponding to the status.
2552 			 */
2553 			pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "%s",
2554 			    pcap_statustostr(status));
2555 		}
2556 
2557 		/*
2558 		 * Undo any operation pointer setting, etc. done by
2559 		 * the activate operation.
2560 		 */
2561 		initialize_ops(p);
2562 	}
2563 	return (status);
2564 }
2565 
2566 pcap_t *
2567 pcap_open_live(const char *device, int snaplen, int promisc, int to_ms, char *errbuf)
2568 {
2569 	pcap_t *p;
2570 	int status;
2571 #ifdef ENABLE_REMOTE
2572 	char host[PCAP_BUF_SIZE + 1];
2573 	char port[PCAP_BUF_SIZE + 1];
2574 	char name[PCAP_BUF_SIZE + 1];
2575 	int srctype;
2576 
2577 	/*
2578 	 * A null device name is equivalent to the "any" device -
2579 	 * which might not be supported on this platform, but
2580 	 * this means that you'll get a "not supported" error
2581 	 * rather than, say, a crash when we try to dereference
2582 	 * the null pointer.
2583 	 */
2584 	if (device == NULL)
2585 		device = "any";
2586 
2587 	/*
2588 	 * Retrofit - we have to make older applications compatible with
2589 	 * remote capture.
2590 	 * So we're calling pcap_open_remote() from here; this is a very
2591 	 * dirty hack.
2592 	 * Obviously, we cannot exploit all the new features; for instance,
2593 	 * we cannot send authentication, we cannot use a UDP data connection,
2594 	 * and so on.
2595 	 */
2596 	if (pcap_parsesrcstr(device, &srctype, host, port, name, errbuf))
2597 		return (NULL);
2598 
2599 	if (srctype == PCAP_SRC_IFREMOTE) {
2600 		/*
2601 		 * Although we already have host, port and iface, we prefer
2602 		 * to pass only 'device' to pcap_open_rpcap(), so that it has
2603 		 * to call pcap_parsesrcstr() again.
2604 		 * This is less optimized, but much clearer.
2605 		 */
2606 		return (pcap_open_rpcap(device, snaplen,
2607 		    promisc ? PCAP_OPENFLAG_PROMISCUOUS : 0, to_ms,
2608 		    NULL, errbuf));
2609 	}
2610 	if (srctype == PCAP_SRC_FILE) {
2611 		pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE, "unknown URL scheme \"file\"");
2612 		return (NULL);
2613 	}
2614 	if (srctype == PCAP_SRC_IFLOCAL) {
2615 		/*
2616 		 * If it starts with rpcap://, that refers to a local device
2617 		 * (no host part in the URL). Remove the rpcap://, and
2618 		 * fall through to the regular open path.
2619 		 */
2620 		if (strncmp(device, PCAP_SRC_IF_STRING, strlen(PCAP_SRC_IF_STRING)) == 0) {
2621 			size_t len = strlen(device) - strlen(PCAP_SRC_IF_STRING) + 1;
2622 
2623 			if (len > 0)
2624 				device += strlen(PCAP_SRC_IF_STRING);
2625 		}
2626 	}
2627 #endif	/* ENABLE_REMOTE */
2628 
2629 	p = pcap_create(device, errbuf);
2630 	if (p == NULL)
2631 		return (NULL);
2632 	status = pcap_set_snaplen(p, snaplen);
2633 	if (status < 0)
2634 		goto fail;
2635 	status = pcap_set_promisc(p, promisc);
2636 	if (status < 0)
2637 		goto fail;
2638 	status = pcap_set_timeout(p, to_ms);
2639 	if (status < 0)
2640 		goto fail;
2641 	/*
2642 	 * Mark this as opened with pcap_open_live(), so that, for
2643 	 * example, we show the full list of DLT_ values, rather
2644 	 * than just the ones that are compatible with capturing
2645 	 * when not in monitor mode.  That allows existing applications
2646 	 * to work the way they used to work, but allows new applications
2647 	 * that know about the new open API to, for example, find out the
2648 	 * DLT_ values that they can select without changing whether
2649 	 * the adapter is in monitor mode or not.
2650 	 */
2651 	p->oldstyle = 1;
2652 	status = pcap_activate(p);
2653 	if (status < 0)
2654 		goto fail;
2655 	return (p);
2656 fail:
2657 	if (status == PCAP_ERROR)
2658 		pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE, "%s: %.*s", device,
2659 		    PCAP_ERRBUF_SIZE - 3, p->errbuf);
2660 	else if (status == PCAP_ERROR_NO_SUCH_DEVICE ||
2661 	    status == PCAP_ERROR_PERM_DENIED ||
2662 	    status == PCAP_ERROR_PROMISC_PERM_DENIED)
2663 		pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE, "%s: %s (%.*s)", device,
2664 		    pcap_statustostr(status), PCAP_ERRBUF_SIZE - 6, p->errbuf);
2665 	else
2666 		pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE, "%s: %s", device,
2667 		    pcap_statustostr(status));
2668 	pcap_close(p);
2669 	return (NULL);
2670 }
2671 
2672 pcap_t *
2673 pcap_open_offline_common(char *ebuf, size_t size)
2674 {
2675 	pcap_t *p;
2676 
2677 	p = pcap_alloc_pcap_t(ebuf, size);
2678 	if (p == NULL)
2679 		return (NULL);
2680 
2681 	p->opt.tstamp_precision = PCAP_TSTAMP_PRECISION_MICRO;
2682 
2683 	return (p);
2684 }
2685 
2686 int
2687 pcap_dispatch(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
2688 {
2689 	return (p->read_op(p, cnt, callback, user));
2690 }
2691 
2692 int
2693 pcap_loop(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
2694 {
2695 	register int n;
2696 
2697 	for (;;) {
2698 		if (p->rfile != NULL) {
2699 			/*
2700 			 * 0 means EOF, so don't loop if we get 0.
2701 			 */
2702 			n = pcap_offline_read(p, cnt, callback, user);
2703 		} else {
2704 			/*
2705 			 * XXX keep reading until we get something
2706 			 * (or an error occurs)
2707 			 */
2708 			do {
2709 				n = p->read_op(p, cnt, callback, user);
2710 			} while (n == 0);
2711 		}
2712 		if (n <= 0)
2713 			return (n);
2714 		if (!PACKET_COUNT_IS_UNLIMITED(cnt)) {
2715 			cnt -= n;
2716 			if (cnt <= 0)
2717 				return (0);
2718 		}
2719 	}
2720 }
2721 
2722 /*
2723  * Force the loop in "pcap_read()" or "pcap_read_offline()" to terminate.
2724  */
2725 void
2726 pcap_breakloop(pcap_t *p)
2727 {
2728 	p->break_loop = 1;
2729 }
2730 
2731 int
2732 pcap_datalink(pcap_t *p)
2733 {
2734 	if (!p->activated)
2735 		return (PCAP_ERROR_NOT_ACTIVATED);
2736 	return (p->linktype);
2737 }
2738 
2739 int
2740 pcap_datalink_ext(pcap_t *p)
2741 {
2742 	if (!p->activated)
2743 		return (PCAP_ERROR_NOT_ACTIVATED);
2744 	return (p->linktype_ext);
2745 }
2746 
2747 int
2748 pcap_list_datalinks(pcap_t *p, int **dlt_buffer)
2749 {
2750 	if (!p->activated)
2751 		return (PCAP_ERROR_NOT_ACTIVATED);
2752 	if (p->dlt_count == 0) {
2753 		/*
2754 		 * We couldn't fetch the list of DLTs, which means
2755 		 * this platform doesn't support changing the
2756 		 * DLT for an interface.  Return a list of DLTs
2757 		 * containing only the DLT this device supports.
2758 		 */
2759 		*dlt_buffer = (int*)malloc(sizeof(**dlt_buffer));
2760 		if (*dlt_buffer == NULL) {
2761 			pcap_fmt_errmsg_for_errno(p->errbuf, sizeof(p->errbuf),
2762 			    errno, "malloc");
2763 			return (PCAP_ERROR);
2764 		}
2765 		**dlt_buffer = p->linktype;
2766 		return (1);
2767 	} else {
2768 		*dlt_buffer = (int*)calloc(sizeof(**dlt_buffer), p->dlt_count);
2769 		if (*dlt_buffer == NULL) {
2770 			pcap_fmt_errmsg_for_errno(p->errbuf, sizeof(p->errbuf),
2771 			    errno, "malloc");
2772 			return (PCAP_ERROR);
2773 		}
2774 		(void)memcpy(*dlt_buffer, p->dlt_list,
2775 		    sizeof(**dlt_buffer) * p->dlt_count);
2776 		return (p->dlt_count);
2777 	}
2778 }
2779 
2780 /*
2781  * In Windows, you might have a library built with one version of the
2782  * C runtime library and an application built with another version of
2783  * the C runtime library, which means that the library might use one
2784  * version of malloc() and free() and the application might use another
2785  * version of malloc() and free().  If so, that means something
2786  * allocated by the library cannot be freed by the application, so we
2787  * need to have a pcap_free_datalinks() routine to free up the list
2788  * allocated by pcap_list_datalinks(), even though it's just a wrapper
2789  * around free().
2790  */
2791 void
2792 pcap_free_datalinks(int *dlt_list)
2793 {
2794 	free(dlt_list);
2795 }
2796 
2797 int
2798 pcap_set_datalink(pcap_t *p, int dlt)
2799 {
2800 	int i;
2801 	const char *dlt_name;
2802 
2803 	if (dlt < 0)
2804 		goto unsupported;
2805 
2806 	if (p->dlt_count == 0 || p->set_datalink_op == NULL) {
2807 		/*
2808 		 * We couldn't fetch the list of DLTs, or we don't
2809 		 * have a "set datalink" operation, which means
2810 		 * this platform doesn't support changing the
2811 		 * DLT for an interface.  Check whether the new
2812 		 * DLT is the one this interface supports.
2813 		 */
2814 		if (p->linktype != dlt)
2815 			goto unsupported;
2816 
2817 		/*
2818 		 * It is, so there's nothing we need to do here.
2819 		 */
2820 		return (0);
2821 	}
2822 	for (i = 0; i < p->dlt_count; i++)
2823 		if (p->dlt_list[i] == (u_int)dlt)
2824 			break;
2825 	if (i >= p->dlt_count)
2826 		goto unsupported;
2827 	if (p->dlt_count == 2 && p->dlt_list[0] == DLT_EN10MB &&
2828 	    dlt == DLT_DOCSIS) {
2829 		/*
2830 		 * This is presumably an Ethernet device, as the first
2831 		 * link-layer type it offers is DLT_EN10MB, and the only
2832 		 * other type it offers is DLT_DOCSIS.  That means that
2833 		 * we can't tell the driver to supply DOCSIS link-layer
2834 		 * headers - we're just pretending that's what we're
2835 		 * getting, as, presumably, we're capturing on a dedicated
2836 		 * link to a Cisco Cable Modem Termination System, and
2837 		 * it's putting raw DOCSIS frames on the wire inside low-level
2838 		 * Ethernet framing.
2839 		 */
2840 		p->linktype = dlt;
2841 		return (0);
2842 	}
2843 	if (p->set_datalink_op(p, dlt) == -1)
2844 		return (-1);
2845 	p->linktype = dlt;
2846 	return (0);
2847 
2848 unsupported:
2849 	dlt_name = pcap_datalink_val_to_name(dlt);
2850 	if (dlt_name != NULL) {
2851 		(void) pcap_snprintf(p->errbuf, sizeof(p->errbuf),
2852 		    "%s is not one of the DLTs supported by this device",
2853 		    dlt_name);
2854 	} else {
2855 		(void) pcap_snprintf(p->errbuf, sizeof(p->errbuf),
2856 		    "DLT %d is not one of the DLTs supported by this device",
2857 		    dlt);
2858 	}
2859 	return (-1);
2860 }
2861 
2862 /*
2863  * This array is designed for mapping upper and lower case letter
2864  * together for a case independent comparison.  The mappings are
2865  * based upon ascii character sequences.
2866  */
2867 static const u_char charmap[] = {
2868 	(u_char)'\000', (u_char)'\001', (u_char)'\002', (u_char)'\003',
2869 	(u_char)'\004', (u_char)'\005', (u_char)'\006', (u_char)'\007',
2870 	(u_char)'\010', (u_char)'\011', (u_char)'\012', (u_char)'\013',
2871 	(u_char)'\014', (u_char)'\015', (u_char)'\016', (u_char)'\017',
2872 	(u_char)'\020', (u_char)'\021', (u_char)'\022', (u_char)'\023',
2873 	(u_char)'\024', (u_char)'\025', (u_char)'\026', (u_char)'\027',
2874 	(u_char)'\030', (u_char)'\031', (u_char)'\032', (u_char)'\033',
2875 	(u_char)'\034', (u_char)'\035', (u_char)'\036', (u_char)'\037',
2876 	(u_char)'\040', (u_char)'\041', (u_char)'\042', (u_char)'\043',
2877 	(u_char)'\044', (u_char)'\045', (u_char)'\046', (u_char)'\047',
2878 	(u_char)'\050', (u_char)'\051', (u_char)'\052', (u_char)'\053',
2879 	(u_char)'\054', (u_char)'\055', (u_char)'\056', (u_char)'\057',
2880 	(u_char)'\060', (u_char)'\061', (u_char)'\062', (u_char)'\063',
2881 	(u_char)'\064', (u_char)'\065', (u_char)'\066', (u_char)'\067',
2882 	(u_char)'\070', (u_char)'\071', (u_char)'\072', (u_char)'\073',
2883 	(u_char)'\074', (u_char)'\075', (u_char)'\076', (u_char)'\077',
2884 	(u_char)'\100', (u_char)'\141', (u_char)'\142', (u_char)'\143',
2885 	(u_char)'\144', (u_char)'\145', (u_char)'\146', (u_char)'\147',
2886 	(u_char)'\150', (u_char)'\151', (u_char)'\152', (u_char)'\153',
2887 	(u_char)'\154', (u_char)'\155', (u_char)'\156', (u_char)'\157',
2888 	(u_char)'\160', (u_char)'\161', (u_char)'\162', (u_char)'\163',
2889 	(u_char)'\164', (u_char)'\165', (u_char)'\166', (u_char)'\167',
2890 	(u_char)'\170', (u_char)'\171', (u_char)'\172', (u_char)'\133',
2891 	(u_char)'\134', (u_char)'\135', (u_char)'\136', (u_char)'\137',
2892 	(u_char)'\140', (u_char)'\141', (u_char)'\142', (u_char)'\143',
2893 	(u_char)'\144', (u_char)'\145', (u_char)'\146', (u_char)'\147',
2894 	(u_char)'\150', (u_char)'\151', (u_char)'\152', (u_char)'\153',
2895 	(u_char)'\154', (u_char)'\155', (u_char)'\156', (u_char)'\157',
2896 	(u_char)'\160', (u_char)'\161', (u_char)'\162', (u_char)'\163',
2897 	(u_char)'\164', (u_char)'\165', (u_char)'\166', (u_char)'\167',
2898 	(u_char)'\170', (u_char)'\171', (u_char)'\172', (u_char)'\173',
2899 	(u_char)'\174', (u_char)'\175', (u_char)'\176', (u_char)'\177',
2900 	(u_char)'\200', (u_char)'\201', (u_char)'\202', (u_char)'\203',
2901 	(u_char)'\204', (u_char)'\205', (u_char)'\206', (u_char)'\207',
2902 	(u_char)'\210', (u_char)'\211', (u_char)'\212', (u_char)'\213',
2903 	(u_char)'\214', (u_char)'\215', (u_char)'\216', (u_char)'\217',
2904 	(u_char)'\220', (u_char)'\221', (u_char)'\222', (u_char)'\223',
2905 	(u_char)'\224', (u_char)'\225', (u_char)'\226', (u_char)'\227',
2906 	(u_char)'\230', (u_char)'\231', (u_char)'\232', (u_char)'\233',
2907 	(u_char)'\234', (u_char)'\235', (u_char)'\236', (u_char)'\237',
2908 	(u_char)'\240', (u_char)'\241', (u_char)'\242', (u_char)'\243',
2909 	(u_char)'\244', (u_char)'\245', (u_char)'\246', (u_char)'\247',
2910 	(u_char)'\250', (u_char)'\251', (u_char)'\252', (u_char)'\253',
2911 	(u_char)'\254', (u_char)'\255', (u_char)'\256', (u_char)'\257',
2912 	(u_char)'\260', (u_char)'\261', (u_char)'\262', (u_char)'\263',
2913 	(u_char)'\264', (u_char)'\265', (u_char)'\266', (u_char)'\267',
2914 	(u_char)'\270', (u_char)'\271', (u_char)'\272', (u_char)'\273',
2915 	(u_char)'\274', (u_char)'\275', (u_char)'\276', (u_char)'\277',
2916 	(u_char)'\300', (u_char)'\341', (u_char)'\342', (u_char)'\343',
2917 	(u_char)'\344', (u_char)'\345', (u_char)'\346', (u_char)'\347',
2918 	(u_char)'\350', (u_char)'\351', (u_char)'\352', (u_char)'\353',
2919 	(u_char)'\354', (u_char)'\355', (u_char)'\356', (u_char)'\357',
2920 	(u_char)'\360', (u_char)'\361', (u_char)'\362', (u_char)'\363',
2921 	(u_char)'\364', (u_char)'\365', (u_char)'\366', (u_char)'\367',
2922 	(u_char)'\370', (u_char)'\371', (u_char)'\372', (u_char)'\333',
2923 	(u_char)'\334', (u_char)'\335', (u_char)'\336', (u_char)'\337',
2924 	(u_char)'\340', (u_char)'\341', (u_char)'\342', (u_char)'\343',
2925 	(u_char)'\344', (u_char)'\345', (u_char)'\346', (u_char)'\347',
2926 	(u_char)'\350', (u_char)'\351', (u_char)'\352', (u_char)'\353',
2927 	(u_char)'\354', (u_char)'\355', (u_char)'\356', (u_char)'\357',
2928 	(u_char)'\360', (u_char)'\361', (u_char)'\362', (u_char)'\363',
2929 	(u_char)'\364', (u_char)'\365', (u_char)'\366', (u_char)'\367',
2930 	(u_char)'\370', (u_char)'\371', (u_char)'\372', (u_char)'\373',
2931 	(u_char)'\374', (u_char)'\375', (u_char)'\376', (u_char)'\377',
2932 };
2933 
2934 int
2935 pcap_strcasecmp(const char *s1, const char *s2)
2936 {
2937 	register const u_char	*cm = charmap,
2938 				*us1 = (const u_char *)s1,
2939 				*us2 = (const u_char *)s2;
2940 
2941 	while (cm[*us1] == cm[*us2++])
2942 		if (*us1++ == '\0')
2943 			return(0);
2944 	return (cm[*us1] - cm[*--us2]);
2945 }
2946 
2947 struct dlt_choice {
2948 	const char *name;
2949 	const char *description;
2950 	int	dlt;
2951 };
2952 
2953 #define DLT_CHOICE(code, description) { #code, description, DLT_ ## code }
2954 #define DLT_CHOICE_SENTINEL { NULL, NULL, 0 }
2955 
2956 static struct dlt_choice dlt_choices[] = {
2957 	DLT_CHOICE(NULL, "BSD loopback"),
2958 	DLT_CHOICE(EN10MB, "Ethernet"),
2959 	DLT_CHOICE(IEEE802, "Token ring"),
2960 	DLT_CHOICE(ARCNET, "BSD ARCNET"),
2961 	DLT_CHOICE(SLIP, "SLIP"),
2962 	DLT_CHOICE(PPP, "PPP"),
2963 	DLT_CHOICE(FDDI, "FDDI"),
2964 	DLT_CHOICE(ATM_RFC1483, "RFC 1483 LLC-encapsulated ATM"),
2965 	DLT_CHOICE(RAW, "Raw IP"),
2966 	DLT_CHOICE(SLIP_BSDOS, "BSD/OS SLIP"),
2967 	DLT_CHOICE(PPP_BSDOS, "BSD/OS PPP"),
2968 	DLT_CHOICE(ATM_CLIP, "Linux Classical IP-over-ATM"),
2969 	DLT_CHOICE(PPP_SERIAL, "PPP over serial"),
2970 	DLT_CHOICE(PPP_ETHER, "PPPoE"),
2971 	DLT_CHOICE(SYMANTEC_FIREWALL, "Symantec Firewall"),
2972 	DLT_CHOICE(C_HDLC, "Cisco HDLC"),
2973 	DLT_CHOICE(IEEE802_11, "802.11"),
2974 	DLT_CHOICE(FRELAY, "Frame Relay"),
2975 	DLT_CHOICE(LOOP, "OpenBSD loopback"),
2976 	DLT_CHOICE(ENC, "OpenBSD encapsulated IP"),
2977 	DLT_CHOICE(LINUX_SLL, "Linux cooked v1"),
2978 	DLT_CHOICE(LTALK, "Localtalk"),
2979 	DLT_CHOICE(PFLOG, "OpenBSD pflog file"),
2980 	DLT_CHOICE(PFSYNC, "Packet filter state syncing"),
2981 	DLT_CHOICE(PRISM_HEADER, "802.11 plus Prism header"),
2982 	DLT_CHOICE(IP_OVER_FC, "RFC 2625 IP-over-Fibre Channel"),
2983 	DLT_CHOICE(SUNATM, "Sun raw ATM"),
2984 	DLT_CHOICE(IEEE802_11_RADIO, "802.11 plus radiotap header"),
2985 	DLT_CHOICE(ARCNET_LINUX, "Linux ARCNET"),
2986 	DLT_CHOICE(JUNIPER_MLPPP, "Juniper Multi-Link PPP"),
2987 	DLT_CHOICE(JUNIPER_MLFR, "Juniper Multi-Link Frame Relay"),
2988 	DLT_CHOICE(JUNIPER_ES, "Juniper Encryption Services PIC"),
2989 	DLT_CHOICE(JUNIPER_GGSN, "Juniper GGSN PIC"),
2990 	DLT_CHOICE(JUNIPER_MFR, "Juniper FRF.16 Frame Relay"),
2991 	DLT_CHOICE(JUNIPER_ATM2, "Juniper ATM2 PIC"),
2992 	DLT_CHOICE(JUNIPER_SERVICES, "Juniper Advanced Services PIC"),
2993 	DLT_CHOICE(JUNIPER_ATM1, "Juniper ATM1 PIC"),
2994 	DLT_CHOICE(APPLE_IP_OVER_IEEE1394, "Apple IP-over-IEEE 1394"),
2995 	DLT_CHOICE(MTP2_WITH_PHDR, "SS7 MTP2 with Pseudo-header"),
2996 	DLT_CHOICE(MTP2, "SS7 MTP2"),
2997 	DLT_CHOICE(MTP3, "SS7 MTP3"),
2998 	DLT_CHOICE(SCCP, "SS7 SCCP"),
2999 	DLT_CHOICE(DOCSIS, "DOCSIS"),
3000 	DLT_CHOICE(LINUX_IRDA, "Linux IrDA"),
3001 	DLT_CHOICE(IEEE802_11_RADIO_AVS, "802.11 plus AVS radio information header"),
3002 	DLT_CHOICE(JUNIPER_MONITOR, "Juniper Passive Monitor PIC"),
3003 	DLT_CHOICE(BACNET_MS_TP, "BACnet MS/TP"),
3004 	DLT_CHOICE(PPP_PPPD, "PPP for pppd, with direction flag"),
3005 	DLT_CHOICE(JUNIPER_PPPOE, "Juniper PPPoE"),
3006 	DLT_CHOICE(JUNIPER_PPPOE_ATM, "Juniper PPPoE/ATM"),
3007 	DLT_CHOICE(GPRS_LLC, "GPRS LLC"),
3008 	DLT_CHOICE(GPF_T, "GPF-T"),
3009 	DLT_CHOICE(GPF_F, "GPF-F"),
3010 	DLT_CHOICE(JUNIPER_PIC_PEER, "Juniper PIC Peer"),
3011 	DLT_CHOICE(ERF_ETH, "Ethernet with Endace ERF header"),
3012 	DLT_CHOICE(ERF_POS, "Packet-over-SONET with Endace ERF header"),
3013 	DLT_CHOICE(LINUX_LAPD, "Linux vISDN LAPD"),
3014 	DLT_CHOICE(JUNIPER_ETHER, "Juniper Ethernet"),
3015 	DLT_CHOICE(JUNIPER_PPP, "Juniper PPP"),
3016 	DLT_CHOICE(JUNIPER_FRELAY, "Juniper Frame Relay"),
3017 	DLT_CHOICE(JUNIPER_CHDLC, "Juniper C-HDLC"),
3018 	DLT_CHOICE(MFR, "FRF.16 Frame Relay"),
3019 	DLT_CHOICE(JUNIPER_VP, "Juniper Voice PIC"),
3020 	DLT_CHOICE(A429, "Arinc 429"),
3021 	DLT_CHOICE(A653_ICM, "Arinc 653 Interpartition Communication"),
3022 	DLT_CHOICE(USB_FREEBSD, "USB with FreeBSD header"),
3023 	DLT_CHOICE(BLUETOOTH_HCI_H4, "Bluetooth HCI UART transport layer"),
3024 	DLT_CHOICE(IEEE802_16_MAC_CPS, "IEEE 802.16 MAC Common Part Sublayer"),
3025 	DLT_CHOICE(USB_LINUX, "USB with Linux header"),
3026 	DLT_CHOICE(CAN20B, "Controller Area Network (CAN) v. 2.0B"),
3027 	DLT_CHOICE(IEEE802_15_4_LINUX, "IEEE 802.15.4 with Linux padding"),
3028 	DLT_CHOICE(PPI, "Per-Packet Information"),
3029 	DLT_CHOICE(IEEE802_16_MAC_CPS_RADIO, "IEEE 802.16 MAC Common Part Sublayer plus radiotap header"),
3030 	DLT_CHOICE(JUNIPER_ISM, "Juniper Integrated Service Module"),
3031 	DLT_CHOICE(IEEE802_15_4, "IEEE 802.15.4 with FCS"),
3032 	DLT_CHOICE(SITA, "SITA pseudo-header"),
3033 	DLT_CHOICE(ERF, "Endace ERF header"),
3034 	DLT_CHOICE(RAIF1, "Ethernet with u10 Networks pseudo-header"),
3035 	DLT_CHOICE(IPMB_KONTRON, "IPMB with Kontron pseudo-header"),
3036 	DLT_CHOICE(JUNIPER_ST, "Juniper Secure Tunnel"),
3037 	DLT_CHOICE(BLUETOOTH_HCI_H4_WITH_PHDR, "Bluetooth HCI UART transport layer plus pseudo-header"),
3038 	DLT_CHOICE(AX25_KISS, "AX.25 with KISS header"),
3039 	DLT_CHOICE(IPMB_LINUX, "IPMB with Linux/Pigeon Point pseudo-header"),
3040 	DLT_CHOICE(IEEE802_15_4_NONASK_PHY, "IEEE 802.15.4 with non-ASK PHY data"),
3041 	DLT_CHOICE(MPLS, "MPLS with label as link-layer header"),
3042 	DLT_CHOICE(LINUX_EVDEV, "Linux evdev events"),
3043 	DLT_CHOICE(USB_LINUX_MMAPPED, "USB with padded Linux header"),
3044 	DLT_CHOICE(DECT, "DECT"),
3045 	DLT_CHOICE(AOS, "AOS Space Data Link protocol"),
3046 	DLT_CHOICE(WIHART, "Wireless HART"),
3047 	DLT_CHOICE(FC_2, "Fibre Channel FC-2"),
3048 	DLT_CHOICE(FC_2_WITH_FRAME_DELIMS, "Fibre Channel FC-2 with frame delimiters"),
3049 	DLT_CHOICE(IPNET, "Solaris ipnet"),
3050 	DLT_CHOICE(CAN_SOCKETCAN, "CAN-bus with SocketCAN headers"),
3051 	DLT_CHOICE(IPV4, "Raw IPv4"),
3052 	DLT_CHOICE(IPV6, "Raw IPv6"),
3053 	DLT_CHOICE(IEEE802_15_4_NOFCS, "IEEE 802.15.4 without FCS"),
3054 	DLT_CHOICE(DBUS, "D-Bus"),
3055 	DLT_CHOICE(JUNIPER_VS, "Juniper Virtual Server"),
3056 	DLT_CHOICE(JUNIPER_SRX_E2E, "Juniper SRX E2E"),
3057 	DLT_CHOICE(JUNIPER_FIBRECHANNEL, "Juniper Fibre Channel"),
3058 	DLT_CHOICE(DVB_CI, "DVB-CI"),
3059 	DLT_CHOICE(MUX27010, "MUX27010"),
3060 	DLT_CHOICE(STANAG_5066_D_PDU, "STANAG 5066 D_PDUs"),
3061 	DLT_CHOICE(JUNIPER_ATM_CEMIC, "Juniper ATM CEMIC"),
3062 	DLT_CHOICE(NFLOG, "Linux netfilter log messages"),
3063 	DLT_CHOICE(NETANALYZER, "Ethernet with Hilscher netANALYZER pseudo-header"),
3064 	DLT_CHOICE(NETANALYZER_TRANSPARENT, "Ethernet with Hilscher netANALYZER pseudo-header and with preamble and SFD"),
3065 	DLT_CHOICE(IPOIB, "RFC 4391 IP-over-Infiniband"),
3066 	DLT_CHOICE(MPEG_2_TS, "MPEG-2 transport stream"),
3067 	DLT_CHOICE(NG40, "ng40 protocol tester Iub/Iur"),
3068 	DLT_CHOICE(NFC_LLCP, "NFC LLCP PDUs with pseudo-header"),
3069 	DLT_CHOICE(INFINIBAND, "InfiniBand"),
3070 	DLT_CHOICE(SCTP, "SCTP"),
3071 	DLT_CHOICE(USBPCAP, "USB with USBPcap header"),
3072 	DLT_CHOICE(RTAC_SERIAL, "Schweitzer Engineering Laboratories RTAC packets"),
3073 	DLT_CHOICE(BLUETOOTH_LE_LL, "Bluetooth Low Energy air interface"),
3074 	DLT_CHOICE(NETLINK, "Linux netlink"),
3075 	DLT_CHOICE(BLUETOOTH_LINUX_MONITOR, "Bluetooth Linux Monitor"),
3076 	DLT_CHOICE(BLUETOOTH_BREDR_BB, "Bluetooth Basic Rate/Enhanced Data Rate baseband packets"),
3077 	DLT_CHOICE(BLUETOOTH_LE_LL_WITH_PHDR, "Bluetooth Low Energy air interface with pseudo-header"),
3078 	DLT_CHOICE(PROFIBUS_DL, "PROFIBUS data link layer"),
3079 	DLT_CHOICE(PKTAP, "Apple DLT_PKTAP"),
3080 	DLT_CHOICE(EPON, "Ethernet with 802.3 Clause 65 EPON preamble"),
3081 	DLT_CHOICE(IPMI_HPM_2, "IPMI trace packets"),
3082 	DLT_CHOICE(ZWAVE_R1_R2, "Z-Wave RF profile R1 and R2 packets"),
3083 	DLT_CHOICE(ZWAVE_R3, "Z-Wave RF profile R3 packets"),
3084 	DLT_CHOICE(WATTSTOPPER_DLM, "WattStopper Digital Lighting Management (DLM) and Legrand Nitoo Open protocol"),
3085 	DLT_CHOICE(ISO_14443, "ISO 14443 messages"),
3086 	DLT_CHOICE(RDS, "IEC 62106 Radio Data System groups"),
3087 	DLT_CHOICE(USB_DARWIN, "USB with Darwin header"),
3088 	DLT_CHOICE(OPENFLOW, "OpenBSD DLT_OPENFLOW"),
3089 	DLT_CHOICE(SDLC, "IBM SDLC frames"),
3090 	DLT_CHOICE(TI_LLN_SNIFFER, "TI LLN sniffer frames"),
3091 	DLT_CHOICE(VSOCK, "Linux vsock"),
3092 	DLT_CHOICE(NORDIC_BLE, "Nordic Semiconductor Bluetooth LE sniffer frames"),
3093 	DLT_CHOICE(DOCSIS31_XRA31, "Excentis XRA-31 DOCSIS 3.1 RF sniffer frames"),
3094 	DLT_CHOICE(ETHERNET_MPACKET, "802.3br mPackets"),
3095 	DLT_CHOICE(DISPLAYPORT_AUX, "DisplayPort AUX channel monitoring data"),
3096 	DLT_CHOICE(LINUX_SLL2, "Linux cooked v2"),
3097 	DLT_CHOICE_SENTINEL
3098 };
3099 
3100 int
3101 pcap_datalink_name_to_val(const char *name)
3102 {
3103 	int i;
3104 
3105 	for (i = 0; dlt_choices[i].name != NULL; i++) {
3106 		if (pcap_strcasecmp(dlt_choices[i].name, name) == 0)
3107 			return (dlt_choices[i].dlt);
3108 	}
3109 	return (-1);
3110 }
3111 
3112 const char *
3113 pcap_datalink_val_to_name(int dlt)
3114 {
3115 	int i;
3116 
3117 	for (i = 0; dlt_choices[i].name != NULL; i++) {
3118 		if (dlt_choices[i].dlt == dlt)
3119 			return (dlt_choices[i].name);
3120 	}
3121 	return (NULL);
3122 }
3123 
3124 const char *
3125 pcap_datalink_val_to_description(int dlt)
3126 {
3127 	int i;
3128 
3129 	for (i = 0; dlt_choices[i].name != NULL; i++) {
3130 		if (dlt_choices[i].dlt == dlt)
3131 			return (dlt_choices[i].description);
3132 	}
3133 	return (NULL);
3134 }
3135 
3136 const char *
3137 pcap_datalink_val_to_description_or_dlt(int dlt)
3138 {
3139         static char unkbuf[40];
3140         const char *description;
3141 
3142         description = pcap_datalink_val_to_description(dlt);
3143         if (description != NULL) {
3144                 return description;
3145         } else {
3146                 (void)pcap_snprintf(unkbuf, sizeof(unkbuf), "DLT %u", dlt);
3147                 return unkbuf;
3148         }
3149 }
3150 
3151 struct tstamp_type_choice {
3152 	const char *name;
3153 	const char *description;
3154 	int	type;
3155 };
3156 
3157 static struct tstamp_type_choice tstamp_type_choices[] = {
3158 	{ "host", "Host", PCAP_TSTAMP_HOST },
3159 	{ "host_lowprec", "Host, low precision", PCAP_TSTAMP_HOST_LOWPREC },
3160 	{ "host_hiprec", "Host, high precision", PCAP_TSTAMP_HOST_HIPREC },
3161 	{ "adapter", "Adapter", PCAP_TSTAMP_ADAPTER },
3162 	{ "adapter_unsynced", "Adapter, not synced with system time", PCAP_TSTAMP_ADAPTER_UNSYNCED },
3163 	{ NULL, NULL, 0 }
3164 };
3165 
3166 int
3167 pcap_tstamp_type_name_to_val(const char *name)
3168 {
3169 	int i;
3170 
3171 	for (i = 0; tstamp_type_choices[i].name != NULL; i++) {
3172 		if (pcap_strcasecmp(tstamp_type_choices[i].name, name) == 0)
3173 			return (tstamp_type_choices[i].type);
3174 	}
3175 	return (PCAP_ERROR);
3176 }
3177 
3178 const char *
3179 pcap_tstamp_type_val_to_name(int tstamp_type)
3180 {
3181 	int i;
3182 
3183 	for (i = 0; tstamp_type_choices[i].name != NULL; i++) {
3184 		if (tstamp_type_choices[i].type == tstamp_type)
3185 			return (tstamp_type_choices[i].name);
3186 	}
3187 	return (NULL);
3188 }
3189 
3190 const char *
3191 pcap_tstamp_type_val_to_description(int tstamp_type)
3192 {
3193 	int i;
3194 
3195 	for (i = 0; tstamp_type_choices[i].name != NULL; i++) {
3196 		if (tstamp_type_choices[i].type == tstamp_type)
3197 			return (tstamp_type_choices[i].description);
3198 	}
3199 	return (NULL);
3200 }
3201 
3202 int
3203 pcap_snapshot(pcap_t *p)
3204 {
3205 	if (!p->activated)
3206 		return (PCAP_ERROR_NOT_ACTIVATED);
3207 	return (p->snapshot);
3208 }
3209 
3210 int
3211 pcap_is_swapped(pcap_t *p)
3212 {
3213 	if (!p->activated)
3214 		return (PCAP_ERROR_NOT_ACTIVATED);
3215 	return (p->swapped);
3216 }
3217 
3218 int
3219 pcap_major_version(pcap_t *p)
3220 {
3221 	if (!p->activated)
3222 		return (PCAP_ERROR_NOT_ACTIVATED);
3223 	return (p->version_major);
3224 }
3225 
3226 int
3227 pcap_minor_version(pcap_t *p)
3228 {
3229 	if (!p->activated)
3230 		return (PCAP_ERROR_NOT_ACTIVATED);
3231 	return (p->version_minor);
3232 }
3233 
3234 int
3235 pcap_bufsize(pcap_t *p)
3236 {
3237 	if (!p->activated)
3238 		return (PCAP_ERROR_NOT_ACTIVATED);
3239 	return (p->bufsize);
3240 }
3241 
3242 FILE *
3243 pcap_file(pcap_t *p)
3244 {
3245 	return (p->rfile);
3246 }
3247 
3248 int
3249 pcap_fileno(pcap_t *p)
3250 {
3251 #ifndef _WIN32
3252 	return (p->fd);
3253 #else
3254 	if (p->handle != INVALID_HANDLE_VALUE)
3255 		return ((int)(DWORD)p->handle);
3256 	else
3257 		return (PCAP_ERROR);
3258 #endif
3259 }
3260 
3261 #if !defined(_WIN32) && !defined(MSDOS)
3262 int
3263 pcap_get_selectable_fd(pcap_t *p)
3264 {
3265 	return (p->selectable_fd);
3266 }
3267 
3268 struct timeval *
3269 pcap_get_required_select_timeout(pcap_t *p)
3270 {
3271 	return (p->required_select_timeout);
3272 }
3273 #endif
3274 
3275 void
3276 pcap_perror(pcap_t *p, const char *prefix)
3277 {
3278 	fprintf(stderr, "%s: %s\n", prefix, p->errbuf);
3279 }
3280 
3281 char *
3282 pcap_geterr(pcap_t *p)
3283 {
3284 	return (p->errbuf);
3285 }
3286 
3287 int
3288 pcap_getnonblock(pcap_t *p, char *errbuf)
3289 {
3290 	int ret;
3291 
3292 	ret = p->getnonblock_op(p);
3293 	if (ret == -1) {
3294 		/*
3295 		 * The get nonblock operation sets p->errbuf; this
3296 		 * function *shouldn't* have had a separate errbuf
3297 		 * argument, as it didn't need one, but I goofed
3298 		 * when adding it.
3299 		 *
3300 		 * We copy the error message to errbuf, so callers
3301 		 * can find it in either place.
3302 		 */
3303 		pcap_strlcpy(errbuf, p->errbuf, PCAP_ERRBUF_SIZE);
3304 	}
3305 	return (ret);
3306 }
3307 
3308 /*
3309  * Get the current non-blocking mode setting, under the assumption that
3310  * it's just the standard POSIX non-blocking flag.
3311  */
3312 #if !defined(_WIN32) && !defined(MSDOS)
3313 int
3314 pcap_getnonblock_fd(pcap_t *p)
3315 {
3316 	int fdflags;
3317 
3318 	fdflags = fcntl(p->fd, F_GETFL, 0);
3319 	if (fdflags == -1) {
3320 		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
3321 		    errno, "F_GETFL");
3322 		return (-1);
3323 	}
3324 	if (fdflags & O_NONBLOCK)
3325 		return (1);
3326 	else
3327 		return (0);
3328 }
3329 #endif
3330 
3331 int
3332 pcap_setnonblock(pcap_t *p, int nonblock, char *errbuf)
3333 {
3334 	int ret;
3335 
3336 	ret = p->setnonblock_op(p, nonblock);
3337 	if (ret == -1) {
3338 		/*
3339 		 * The set nonblock operation sets p->errbuf; this
3340 		 * function *shouldn't* have had a separate errbuf
3341 		 * argument, as it didn't need one, but I goofed
3342 		 * when adding it.
3343 		 *
3344 		 * We copy the error message to errbuf, so callers
3345 		 * can find it in either place.
3346 		 */
3347 		pcap_strlcpy(errbuf, p->errbuf, PCAP_ERRBUF_SIZE);
3348 	}
3349 	return (ret);
3350 }
3351 
3352 #if !defined(_WIN32) && !defined(MSDOS)
3353 /*
3354  * Set non-blocking mode, under the assumption that it's just the
3355  * standard POSIX non-blocking flag.  (This can be called by the
3356  * per-platform non-blocking-mode routine if that routine also
3357  * needs to do some additional work.)
3358  */
3359 int
3360 pcap_setnonblock_fd(pcap_t *p, int nonblock)
3361 {
3362 	int fdflags;
3363 
3364 	fdflags = fcntl(p->fd, F_GETFL, 0);
3365 	if (fdflags == -1) {
3366 		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
3367 		    errno, "F_GETFL");
3368 		return (-1);
3369 	}
3370 	if (nonblock)
3371 		fdflags |= O_NONBLOCK;
3372 	else
3373 		fdflags &= ~O_NONBLOCK;
3374 	if (fcntl(p->fd, F_SETFL, fdflags) == -1) {
3375 		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
3376 		    errno, "F_SETFL");
3377 		return (-1);
3378 	}
3379 	return (0);
3380 }
3381 #endif
3382 
3383 /*
3384  * Generate error strings for PCAP_ERROR_ and PCAP_WARNING_ values.
3385  */
3386 const char *
3387 pcap_statustostr(int errnum)
3388 {
3389 	static char ebuf[15+10+1];
3390 
3391 	switch (errnum) {
3392 
3393 	case PCAP_WARNING:
3394 		return("Generic warning");
3395 
3396 	case PCAP_WARNING_TSTAMP_TYPE_NOTSUP:
3397 		return ("That type of time stamp is not supported by that device");
3398 
3399 	case PCAP_WARNING_PROMISC_NOTSUP:
3400 		return ("That device doesn't support promiscuous mode");
3401 
3402 	case PCAP_ERROR:
3403 		return("Generic error");
3404 
3405 	case PCAP_ERROR_BREAK:
3406 		return("Loop terminated by pcap_breakloop");
3407 
3408 	case PCAP_ERROR_NOT_ACTIVATED:
3409 		return("The pcap_t has not been activated");
3410 
3411 	case PCAP_ERROR_ACTIVATED:
3412 		return ("The setting can't be changed after the pcap_t is activated");
3413 
3414 	case PCAP_ERROR_NO_SUCH_DEVICE:
3415 		return ("No such device exists");
3416 
3417 	case PCAP_ERROR_RFMON_NOTSUP:
3418 		return ("That device doesn't support monitor mode");
3419 
3420 	case PCAP_ERROR_NOT_RFMON:
3421 		return ("That operation is supported only in monitor mode");
3422 
3423 	case PCAP_ERROR_PERM_DENIED:
3424 		return ("You don't have permission to capture on that device");
3425 
3426 	case PCAP_ERROR_IFACE_NOT_UP:
3427 		return ("That device is not up");
3428 
3429 	case PCAP_ERROR_CANTSET_TSTAMP_TYPE:
3430 		return ("That device doesn't support setting the time stamp type");
3431 
3432 	case PCAP_ERROR_PROMISC_PERM_DENIED:
3433 		return ("You don't have permission to capture in promiscuous mode on that device");
3434 
3435 	case PCAP_ERROR_TSTAMP_PRECISION_NOTSUP:
3436 		return ("That device doesn't support that time stamp precision");
3437 	}
3438 	(void)pcap_snprintf(ebuf, sizeof ebuf, "Unknown error: %d", errnum);
3439 	return(ebuf);
3440 }
3441 
3442 /*
3443  * Not all systems have strerror().
3444  */
3445 const char *
3446 pcap_strerror(int errnum)
3447 {
3448 #ifdef HAVE_STRERROR
3449 #ifdef _WIN32
3450 	static char errbuf[PCAP_ERRBUF_SIZE];
3451 	errno_t err = strerror_s(errbuf, PCAP_ERRBUF_SIZE, errnum);
3452 
3453 	if (err != 0) /* err = 0 if successful */
3454 		pcap_strlcpy(errbuf, "strerror_s() error", PCAP_ERRBUF_SIZE);
3455 	return (errbuf);
3456 #else
3457 	return (strerror(errnum));
3458 #endif /* _WIN32 */
3459 #else
3460 	extern int sys_nerr;
3461 	extern const char *const sys_errlist[];
3462 	static char errbuf[PCAP_ERRBUF_SIZE];
3463 
3464 	if ((unsigned int)errnum < sys_nerr)
3465 		return ((char *)sys_errlist[errnum]);
3466 	(void)pcap_snprintf(errbuf, sizeof errbuf, "Unknown error: %d", errnum);
3467 	return (errbuf);
3468 #endif
3469 }
3470 
3471 int
3472 pcap_setfilter(pcap_t *p, struct bpf_program *fp)
3473 {
3474 	return (p->setfilter_op(p, fp));
3475 }
3476 
3477 /*
3478  * Set direction flag, which controls whether we accept only incoming
3479  * packets, only outgoing packets, or both.
3480  * Note that, depending on the platform, some or all direction arguments
3481  * might not be supported.
3482  */
3483 int
3484 pcap_setdirection(pcap_t *p, pcap_direction_t d)
3485 {
3486 	if (p->setdirection_op == NULL) {
3487 		pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
3488 		    "Setting direction is not implemented on this platform");
3489 		return (-1);
3490 	} else
3491 		return (p->setdirection_op(p, d));
3492 }
3493 
3494 int
3495 pcap_stats(pcap_t *p, struct pcap_stat *ps)
3496 {
3497 	return (p->stats_op(p, ps));
3498 }
3499 
3500 #ifdef _WIN32
3501 struct pcap_stat *
3502 pcap_stats_ex(pcap_t *p, int *pcap_stat_size)
3503 {
3504 	return (p->stats_ex_op(p, pcap_stat_size));
3505 }
3506 
3507 int
3508 pcap_setbuff(pcap_t *p, int dim)
3509 {
3510 	return (p->setbuff_op(p, dim));
3511 }
3512 
3513 int
3514 pcap_setmode(pcap_t *p, int mode)
3515 {
3516 	return (p->setmode_op(p, mode));
3517 }
3518 
3519 int
3520 pcap_setmintocopy(pcap_t *p, int size)
3521 {
3522 	return (p->setmintocopy_op(p, size));
3523 }
3524 
3525 HANDLE
3526 pcap_getevent(pcap_t *p)
3527 {
3528 	return (p->getevent_op(p));
3529 }
3530 
3531 int
3532 pcap_oid_get_request(pcap_t *p, bpf_u_int32 oid, void *data, size_t *lenp)
3533 {
3534 	return (p->oid_get_request_op(p, oid, data, lenp));
3535 }
3536 
3537 int
3538 pcap_oid_set_request(pcap_t *p, bpf_u_int32 oid, const void *data, size_t *lenp)
3539 {
3540 	return (p->oid_set_request_op(p, oid, data, lenp));
3541 }
3542 
3543 pcap_send_queue *
3544 pcap_sendqueue_alloc(u_int memsize)
3545 {
3546 	pcap_send_queue *tqueue;
3547 
3548 	/* Allocate the queue */
3549 	tqueue = (pcap_send_queue *)malloc(sizeof(pcap_send_queue));
3550 	if (tqueue == NULL){
3551 		return (NULL);
3552 	}
3553 
3554 	/* Allocate the buffer */
3555 	tqueue->buffer = (char *)malloc(memsize);
3556 	if (tqueue->buffer == NULL) {
3557 		free(tqueue);
3558 		return (NULL);
3559 	}
3560 
3561 	tqueue->maxlen = memsize;
3562 	tqueue->len = 0;
3563 
3564 	return (tqueue);
3565 }
3566 
3567 void
3568 pcap_sendqueue_destroy(pcap_send_queue *queue)
3569 {
3570 	free(queue->buffer);
3571 	free(queue);
3572 }
3573 
3574 int
3575 pcap_sendqueue_queue(pcap_send_queue *queue, const struct pcap_pkthdr *pkt_header, const u_char *pkt_data)
3576 {
3577 	if (queue->len + sizeof(struct pcap_pkthdr) + pkt_header->caplen > queue->maxlen){
3578 		return (-1);
3579 	}
3580 
3581 	/* Copy the pcap_pkthdr header*/
3582 	memcpy(queue->buffer + queue->len, pkt_header, sizeof(struct pcap_pkthdr));
3583 	queue->len += sizeof(struct pcap_pkthdr);
3584 
3585 	/* copy the packet */
3586 	memcpy(queue->buffer + queue->len, pkt_data, pkt_header->caplen);
3587 	queue->len += pkt_header->caplen;
3588 
3589 	return (0);
3590 }
3591 
3592 u_int
3593 pcap_sendqueue_transmit(pcap_t *p, pcap_send_queue *queue, int sync)
3594 {
3595 	return (p->sendqueue_transmit_op(p, queue, sync));
3596 }
3597 
3598 int
3599 pcap_setuserbuffer(pcap_t *p, int size)
3600 {
3601 	return (p->setuserbuffer_op(p, size));
3602 }
3603 
3604 int
3605 pcap_live_dump(pcap_t *p, char *filename, int maxsize, int maxpacks)
3606 {
3607 	return (p->live_dump_op(p, filename, maxsize, maxpacks));
3608 }
3609 
3610 int
3611 pcap_live_dump_ended(pcap_t *p, int sync)
3612 {
3613 	return (p->live_dump_ended_op(p, sync));
3614 }
3615 
3616 PAirpcapHandle
3617 pcap_get_airpcap_handle(pcap_t *p)
3618 {
3619 	PAirpcapHandle handle;
3620 
3621 	handle = p->get_airpcap_handle_op(p);
3622 	if (handle == NULL) {
3623 		(void)pcap_snprintf(p->errbuf, sizeof(p->errbuf),
3624 		    "This isn't an AirPcap device");
3625 	}
3626 	return (handle);
3627 }
3628 #endif
3629 
3630 /*
3631  * On some platforms, we need to clean up promiscuous or monitor mode
3632  * when we close a device - and we want that to happen even if the
3633  * application just exits without explicitl closing devices.
3634  * On those platforms, we need to register a "close all the pcaps"
3635  * routine to be called when we exit, and need to maintain a list of
3636  * pcaps that need to be closed to clean up modes.
3637  *
3638  * XXX - not thread-safe.
3639  */
3640 
3641 /*
3642  * List of pcaps on which we've done something that needs to be
3643  * cleaned up.
3644  * If there are any such pcaps, we arrange to call "pcap_close_all()"
3645  * when we exit, and have it close all of them.
3646  */
3647 static struct pcap *pcaps_to_close;
3648 
3649 /*
3650  * TRUE if we've already called "atexit()" to cause "pcap_close_all()" to
3651  * be called on exit.
3652  */
3653 static int did_atexit;
3654 
3655 static void
3656 pcap_close_all(void)
3657 {
3658 	struct pcap *handle;
3659 
3660 	while ((handle = pcaps_to_close) != NULL)
3661 		pcap_close(handle);
3662 }
3663 
3664 int
3665 pcap_do_addexit(pcap_t *p)
3666 {
3667 	/*
3668 	 * If we haven't already done so, arrange to have
3669 	 * "pcap_close_all()" called when we exit.
3670 	 */
3671 	if (!did_atexit) {
3672 		if (atexit(pcap_close_all) != 0) {
3673 			/*
3674 			 * "atexit()" failed; let our caller know.
3675 			 */
3676 			pcap_strlcpy(p->errbuf, "atexit failed", PCAP_ERRBUF_SIZE);
3677 			return (0);
3678 		}
3679 		did_atexit = 1;
3680 	}
3681 	return (1);
3682 }
3683 
3684 void
3685 pcap_add_to_pcaps_to_close(pcap_t *p)
3686 {
3687 	p->next = pcaps_to_close;
3688 	pcaps_to_close = p;
3689 }
3690 
3691 void
3692 pcap_remove_from_pcaps_to_close(pcap_t *p)
3693 {
3694 	pcap_t *pc, *prevpc;
3695 
3696 	for (pc = pcaps_to_close, prevpc = NULL; pc != NULL;
3697 	    prevpc = pc, pc = pc->next) {
3698 		if (pc == p) {
3699 			/*
3700 			 * Found it.  Remove it from the list.
3701 			 */
3702 			if (prevpc == NULL) {
3703 				/*
3704 				 * It was at the head of the list.
3705 				 */
3706 				pcaps_to_close = pc->next;
3707 			} else {
3708 				/*
3709 				 * It was in the middle of the list.
3710 				 */
3711 				prevpc->next = pc->next;
3712 			}
3713 			break;
3714 		}
3715 	}
3716 }
3717 
3718 void
3719 pcap_cleanup_live_common(pcap_t *p)
3720 {
3721 	if (p->buffer != NULL) {
3722 		free(p->buffer);
3723 		p->buffer = NULL;
3724 	}
3725 	if (p->dlt_list != NULL) {
3726 		free(p->dlt_list);
3727 		p->dlt_list = NULL;
3728 		p->dlt_count = 0;
3729 	}
3730 	if (p->tstamp_type_list != NULL) {
3731 		free(p->tstamp_type_list);
3732 		p->tstamp_type_list = NULL;
3733 		p->tstamp_type_count = 0;
3734 	}
3735 	if (p->tstamp_precision_list != NULL) {
3736 		free(p->tstamp_precision_list);
3737 		p->tstamp_precision_list = NULL;
3738 		p->tstamp_precision_count = 0;
3739 	}
3740 	pcap_freecode(&p->fcode);
3741 #if !defined(_WIN32) && !defined(MSDOS)
3742 	if (p->fd >= 0) {
3743 		close(p->fd);
3744 		p->fd = -1;
3745 	}
3746 	p->selectable_fd = -1;
3747 #endif
3748 }
3749 
3750 /*
3751  * API compatible with WinPcap's "send a packet" routine - returns -1
3752  * on error, 0 otherwise.
3753  *
3754  * XXX - what if we get a short write?
3755  */
3756 int
3757 pcap_sendpacket(pcap_t *p, const u_char *buf, int size)
3758 {
3759 	if (p->inject_op(p, buf, size) == -1)
3760 		return (-1);
3761 	return (0);
3762 }
3763 
3764 /*
3765  * API compatible with OpenBSD's "send a packet" routine - returns -1 on
3766  * error, number of bytes written otherwise.
3767  */
3768 int
3769 pcap_inject(pcap_t *p, const void *buf, size_t size)
3770 {
3771 	return (p->inject_op(p, buf, size));
3772 }
3773 
3774 void
3775 pcap_close(pcap_t *p)
3776 {
3777 	if (p->opt.device != NULL)
3778 		free(p->opt.device);
3779 	p->cleanup_op(p);
3780 	free(p);
3781 }
3782 
3783 /*
3784  * Given a BPF program, a pcap_pkthdr structure for a packet, and the raw
3785  * data for the packet, check whether the packet passes the filter.
3786  * Returns the return value of the filter program, which will be zero if
3787  * the packet doesn't pass and non-zero if the packet does pass.
3788  */
3789 int
3790 pcap_offline_filter(const struct bpf_program *fp, const struct pcap_pkthdr *h,
3791     const u_char *pkt)
3792 {
3793 	const struct bpf_insn *fcode = fp->bf_insns;
3794 
3795 	if (fcode != NULL)
3796 		return (bpf_filter(fcode, pkt, h->len, h->caplen));
3797 	else
3798 		return (0);
3799 }
3800 
3801 static int
3802 pcap_can_set_rfmon_dead(pcap_t *p)
3803 {
3804 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
3805 	    "Rfmon mode doesn't apply on a pcap_open_dead pcap_t");
3806 	return (PCAP_ERROR);
3807 }
3808 
3809 static int
3810 pcap_read_dead(pcap_t *p, int cnt _U_, pcap_handler callback _U_,
3811     u_char *user _U_)
3812 {
3813 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
3814 	    "Packets aren't available from a pcap_open_dead pcap_t");
3815 	return (-1);
3816 }
3817 
3818 static int
3819 pcap_inject_dead(pcap_t *p, const void *buf _U_, size_t size _U_)
3820 {
3821 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
3822 	    "Packets can't be sent on a pcap_open_dead pcap_t");
3823 	return (-1);
3824 }
3825 
3826 static int
3827 pcap_setfilter_dead(pcap_t *p, struct bpf_program *fp _U_)
3828 {
3829 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
3830 	    "A filter cannot be set on a pcap_open_dead pcap_t");
3831 	return (-1);
3832 }
3833 
3834 static int
3835 pcap_setdirection_dead(pcap_t *p, pcap_direction_t d _U_)
3836 {
3837 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
3838 	    "The packet direction cannot be set on a pcap_open_dead pcap_t");
3839 	return (-1);
3840 }
3841 
3842 static int
3843 pcap_set_datalink_dead(pcap_t *p, int dlt _U_)
3844 {
3845 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
3846 	    "The link-layer header type cannot be set on a pcap_open_dead pcap_t");
3847 	return (-1);
3848 }
3849 
3850 static int
3851 pcap_getnonblock_dead(pcap_t *p)
3852 {
3853 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
3854 	    "A pcap_open_dead pcap_t does not have a non-blocking mode setting");
3855 	return (-1);
3856 }
3857 
3858 static int
3859 pcap_setnonblock_dead(pcap_t *p, int nonblock _U_)
3860 {
3861 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
3862 	    "A pcap_open_dead pcap_t does not have a non-blocking mode setting");
3863 	return (-1);
3864 }
3865 
3866 static int
3867 pcap_stats_dead(pcap_t *p, struct pcap_stat *ps _U_)
3868 {
3869 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
3870 	    "Statistics aren't available from a pcap_open_dead pcap_t");
3871 	return (-1);
3872 }
3873 
3874 #ifdef _WIN32
3875 struct pcap_stat *
3876 pcap_stats_ex_dead(pcap_t *p, int *pcap_stat_size _U_)
3877 {
3878 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
3879 	    "Statistics aren't available from a pcap_open_dead pcap_t");
3880 	return (NULL);
3881 }
3882 
3883 static int
3884 pcap_setbuff_dead(pcap_t *p, int dim)
3885 {
3886 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
3887 	    "The kernel buffer size cannot be set on a pcap_open_dead pcap_t");
3888 	return (-1);
3889 }
3890 
3891 static int
3892 pcap_setmode_dead(pcap_t *p, int mode)
3893 {
3894 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
3895 	    "impossible to set mode on a pcap_open_dead pcap_t");
3896 	return (-1);
3897 }
3898 
3899 static int
3900 pcap_setmintocopy_dead(pcap_t *p, int size)
3901 {
3902 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
3903 	    "The mintocopy parameter cannot be set on a pcap_open_dead pcap_t");
3904 	return (-1);
3905 }
3906 
3907 static HANDLE
3908 pcap_getevent_dead(pcap_t *p)
3909 {
3910 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
3911 	    "A pcap_open_dead pcap_t has no event handle");
3912 	return (INVALID_HANDLE_VALUE);
3913 }
3914 
3915 static int
3916 pcap_oid_get_request_dead(pcap_t *p, bpf_u_int32 oid _U_, void *data _U_,
3917     size_t *lenp _U_)
3918 {
3919 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
3920 	    "An OID get request cannot be performed on a pcap_open_dead pcap_t");
3921 	return (PCAP_ERROR);
3922 }
3923 
3924 static int
3925 pcap_oid_set_request_dead(pcap_t *p, bpf_u_int32 oid _U_, const void *data _U_,
3926     size_t *lenp _U_)
3927 {
3928 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
3929 	    "An OID set request cannot be performed on a pcap_open_dead pcap_t");
3930 	return (PCAP_ERROR);
3931 }
3932 
3933 static u_int
3934 pcap_sendqueue_transmit_dead(pcap_t *p, pcap_send_queue *queue, int sync)
3935 {
3936 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
3937 	    "Packets cannot be transmitted on a pcap_open_dead pcap_t");
3938 	return (0);
3939 }
3940 
3941 static int
3942 pcap_setuserbuffer_dead(pcap_t *p, int size)
3943 {
3944 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
3945 	    "The user buffer cannot be set on a pcap_open_dead pcap_t");
3946 	return (-1);
3947 }
3948 
3949 static int
3950 pcap_live_dump_dead(pcap_t *p, char *filename, int maxsize, int maxpacks)
3951 {
3952 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
3953 	    "Live packet dumping cannot be performed on a pcap_open_dead pcap_t");
3954 	return (-1);
3955 }
3956 
3957 static int
3958 pcap_live_dump_ended_dead(pcap_t *p, int sync)
3959 {
3960 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
3961 	    "Live packet dumping cannot be performed on a pcap_open_dead pcap_t");
3962 	return (-1);
3963 }
3964 
3965 static PAirpcapHandle
3966 pcap_get_airpcap_handle_dead(pcap_t *p)
3967 {
3968 	return (NULL);
3969 }
3970 #endif /* _WIN32 */
3971 
3972 static void
3973 pcap_cleanup_dead(pcap_t *p _U_)
3974 {
3975 	/* Nothing to do. */
3976 }
3977 
3978 pcap_t *
3979 pcap_open_dead_with_tstamp_precision(int linktype, int snaplen, u_int precision)
3980 {
3981 	pcap_t *p;
3982 
3983 	switch (precision) {
3984 
3985 	case PCAP_TSTAMP_PRECISION_MICRO:
3986 	case PCAP_TSTAMP_PRECISION_NANO:
3987 		break;
3988 
3989 	default:
3990 		/*
3991 		 * This doesn't really matter, but we don't have any way
3992 		 * to report particular errors, so the only failure we
3993 		 * should have is a memory allocation failure.  Just
3994 		 * pick microsecond precision.
3995 		 */
3996 		precision = PCAP_TSTAMP_PRECISION_MICRO;
3997 		break;
3998 	}
3999 	p = malloc(sizeof(*p));
4000 	if (p == NULL)
4001 		return NULL;
4002 	memset (p, 0, sizeof(*p));
4003 	p->snapshot = snaplen;
4004 	p->linktype = linktype;
4005 	p->opt.tstamp_precision = precision;
4006 	p->can_set_rfmon_op = pcap_can_set_rfmon_dead;
4007 	p->read_op = pcap_read_dead;
4008 	p->inject_op = pcap_inject_dead;
4009 	p->setfilter_op = pcap_setfilter_dead;
4010 	p->setdirection_op = pcap_setdirection_dead;
4011 	p->set_datalink_op = pcap_set_datalink_dead;
4012 	p->getnonblock_op = pcap_getnonblock_dead;
4013 	p->setnonblock_op = pcap_setnonblock_dead;
4014 	p->stats_op = pcap_stats_dead;
4015 #ifdef _WIN32
4016 	p->stats_ex_op = pcap_stats_ex_dead;
4017 	p->setbuff_op = pcap_setbuff_dead;
4018 	p->setmode_op = pcap_setmode_dead;
4019 	p->setmintocopy_op = pcap_setmintocopy_dead;
4020 	p->getevent_op = pcap_getevent_dead;
4021 	p->oid_get_request_op = pcap_oid_get_request_dead;
4022 	p->oid_set_request_op = pcap_oid_set_request_dead;
4023 	p->sendqueue_transmit_op = pcap_sendqueue_transmit_dead;
4024 	p->setuserbuffer_op = pcap_setuserbuffer_dead;
4025 	p->live_dump_op = pcap_live_dump_dead;
4026 	p->live_dump_ended_op = pcap_live_dump_ended_dead;
4027 	p->get_airpcap_handle_op = pcap_get_airpcap_handle_dead;
4028 #endif
4029 	p->cleanup_op = pcap_cleanup_dead;
4030 
4031 	/*
4032 	 * A "dead" pcap_t never requires special BPF code generation.
4033 	 */
4034 	p->bpf_codegen_flags = 0;
4035 
4036 	p->activated = 1;
4037 	return (p);
4038 }
4039 
4040 pcap_t *
4041 pcap_open_dead(int linktype, int snaplen)
4042 {
4043 	return (pcap_open_dead_with_tstamp_precision(linktype, snaplen,
4044 	    PCAP_TSTAMP_PRECISION_MICRO));
4045 }
4046 
4047 #ifdef YYDEBUG
4048 /*
4049  * Set the internal "debug printout" flag for the filter expression parser.
4050  * The code to print that stuff is present only if YYDEBUG is defined, so
4051  * the flag, and the routine to set it, are defined only if YYDEBUG is
4052  * defined.
4053  *
4054  * This is intended for libpcap developers, not for general use.
4055  * If you want to set these in a program, you'll have to declare this
4056  * routine yourself, with the appropriate DLL import attribute on Windows;
4057  * it's not declared in any header file, and won't be declared in any
4058  * header file provided by libpcap.
4059  */
4060 PCAP_API void pcap_set_parser_debug(int value);
4061 
4062 PCAP_API_DEF void
4063 pcap_set_parser_debug(int value)
4064 {
4065 	pcap_debug = value;
4066 }
4067 #endif
4068