1 /*        $NetBSD: pcap.c,v 1.12 2024/09/02 15:33:37 christos Exp $   */
2 
3 /*
4  * Copyright (c) 1993, 1994, 1995, 1996, 1997, 1998
5  *        The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *        This product includes software developed by the Computer Systems
18  *        Engineering Group at Lawrence Berkeley Laboratory.
19  * 4. Neither the name of the University nor of the Laboratory may be used
20  *    to endorse or promote products derived from this software without
21  *    specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/cdefs.h>
37 __RCSID("$NetBSD: pcap.c,v 1.12 2024/09/02 15:33:37 christos Exp $");
38 
39 #include <config.h>
40 
41 /* Get the same variety of strerror_r() as Autoconf/CMake has detected. */
42 #include "ftmacros.h"
43 
44 #include <pcap-types.h>
45 #ifndef _WIN32
46 #include <sys/param.h>
47 #ifndef MSDOS
48 #include <sys/file.h>
49 #endif
50 #include <sys/ioctl.h>
51 #include <sys/socket.h>
52 #ifdef HAVE_SYS_SOCKIO_H
53 #include <sys/sockio.h>
54 #endif
55 
56 struct mbuf;                  /* Squelch compiler warnings on some platforms for */
57 struct rtentry;               /* declarations in <net/if.h> */
58 #include <net/if.h>
59 #include <netinet/in.h>
60 #endif /* _WIN32 */
61 
62 #include <stdio.h>
63 #include <stdlib.h>
64 #include <string.h>
65 #if !defined(_MSC_VER) && !defined(__BORLANDC__) && !defined(__MINGW32__)
66 #include <unistd.h>
67 #endif
68 #include <fcntl.h>
69 #include <errno.h>
70 #include <limits.h>
71 
72 #include "diag-control.h"
73 
74 #include "thread-local.h"
75 
76 #ifdef HAVE_OS_PROTO_H
77 #include "os-proto.h"
78 #endif
79 
80 #ifdef MSDOS
81 #include "pcap-dos.h"
82 #endif
83 
84 #include "pcap-int.h"
85 
86 #include "optimize.h"
87 
88 #ifdef HAVE_DAG_API
89 #include "pcap-dag.h"
90 #endif /* HAVE_DAG_API */
91 
92 #ifdef HAVE_SEPTEL_API
93 #include "pcap-septel.h"
94 #endif /* HAVE_SEPTEL_API */
95 
96 #ifdef HAVE_SNF_API
97 #include "pcap-snf.h"
98 #endif /* HAVE_SNF_API */
99 
100 #ifdef HAVE_TC_API
101 #include "pcap-tc.h"
102 #endif /* HAVE_TC_API */
103 
104 #ifdef PCAP_SUPPORT_LINUX_USBMON
105 #include "pcap-usb-linux.h"
106 #endif
107 
108 #ifdef PCAP_SUPPORT_BT
109 #include "pcap-bt-linux.h"
110 #endif
111 
112 #ifdef PCAP_SUPPORT_BT_MONITOR
113 #include "pcap-bt-monitor-linux.h"
114 #endif
115 
116 #ifdef PCAP_SUPPORT_NETFILTER
117 #include "pcap-netfilter-linux.h"
118 #endif
119 
120 #ifdef PCAP_SUPPORT_NETMAP
121 #include "pcap-netmap.h"
122 #endif
123 
124 #ifdef PCAP_SUPPORT_DBUS
125 #include "pcap-dbus.h"
126 #endif
127 
128 #ifdef PCAP_SUPPORT_RPCAP
129 #include "pcap-rpcap-unix.h"
130 #endif
131 
132 #ifdef PCAP_SUPPORT_RDMASNIFF
133 #include "pcap-rdmasniff.h"
134 #endif
135 
136 #ifdef PCAP_SUPPORT_DPDK
137 #include "pcap-dpdk.h"
138 #endif
139 
140 #ifdef HAVE_AIRPCAP_API
141 #include "pcap-airpcap.h"
142 #endif
143 
144 #ifdef _WIN32
145 /*
146  * To quote the WSAStartup() documentation:
147  *
148  *   The WSAStartup function typically leads to protocol-specific helper
149  *   DLLs being loaded. As a result, the WSAStartup function should not
150  *   be called from the DllMain function in a application DLL. This can
151  *   potentially cause deadlocks.
152  *
153  * and the WSACleanup() documentation:
154  *
155  *   The WSACleanup function typically leads to protocol-specific helper
156  *   DLLs being unloaded. As a result, the WSACleanup function should not
157  *   be called from the DllMain function in a application DLL. This can
158  *   potentially cause deadlocks.
159  *
160  * So we don't initialize Winsock in a DllMain() routine.
161  *
162  * pcap_init() should be called to initialize pcap on both UN*X and
163  * Windows; it will initialize Winsock on Windows.  (It will also be
164  * initialized as needed if pcap_init() hasn't been called.)
165  */
166 
167 /*
168  * Shut down Winsock.
169  *
170  * Ignores the return value of WSACleanup(); given that this is
171  * an atexit() routine, there's nothing much we can do about
172  * a failure.
173  */
174 static void
internal_wsockfini(void)175 internal_wsockfini(void)
176 {
177           WSACleanup();
178 }
179 
180 /*
181  * Start Winsock.
182  * Internal routine.
183  */
184 static int
internal_wsockinit(char * errbuf)185 internal_wsockinit(char *errbuf)
186 {
187           WORD wVersionRequested;
188           WSADATA wsaData;
189           static int err = -1;
190           static int done = 0;
191           int status;
192 
193           if (done)
194                     return (err);
195 
196           /*
197            * Versions of Windows that don't support Winsock 2.2 are
198            * too old for us.
199            */
200           wVersionRequested = MAKEWORD(2, 2);
201           status = WSAStartup(wVersionRequested, &wsaData);
202           done = 1;
203           if (status != 0) {
204                     if (errbuf != NULL) {
205                               pcapint_fmt_errmsg_for_win32_err(errbuf, PCAP_ERRBUF_SIZE,
206                                   status, "WSAStartup() failed");
207                     }
208                     return (err);
209           }
210           atexit(internal_wsockfini);
211           err = 0;
212           return (err);
213 }
214 
215 /*
216  * Exported in case some applications using WinPcap/Npcap called it,
217  * even though it wasn't exported.
218  */
219 int
wsockinit(void)220 wsockinit(void)
221 {
222           return (internal_wsockinit(NULL));
223 }
224 
225 /*
226  * This is the exported function; new programs should call this.
227  * *Newer* programs should call pcap_init().
228  */
229 int
pcap_wsockinit(void)230 pcap_wsockinit(void)
231 {
232           return (internal_wsockinit(NULL));
233 }
234 #endif /* _WIN32 */
235 
236 /*
237  * Do whatever initialization is needed for libpcap.
238  *
239  * The argument specifies whether we use the local code page or UTF-8
240  * for strings; on UN*X, we just assume UTF-8 in places where the encoding
241  * would matter, whereas, on Windows, we use the local code page for
242  * PCAP_CHAR_ENC_LOCAL and UTF-8 for PCAP_CHAR_ENC_UTF_8.
243  *
244  * On Windows, we also disable the hack in pcap_create() to deal with
245  * being handed UTF-16 strings, because if the user calls this they're
246  * explicitly declaring that they will either be passing local code
247  * page strings or UTF-8 strings, so we don't need to allow UTF-16LE
248  * strings to be passed.  For good measure, on Windows *and* UN*X,
249  * we disable pcap_lookupdev(), to prevent anybody from even
250  * *trying* to pass the result of pcap_lookupdev() - which might be
251  * UTF-16LE on Windows, for ugly compatibility reasons - to pcap_create()
252  * or pcap_open_live() or pcap_open().
253  *
254  * Returns 0 on success, -1 on error.
255  */
256 int pcapint_new_api;                    /* pcap_lookupdev() always fails */
257 int pcapint_utf_8_mode;                 /* Strings should be in UTF-8. */
258 
259 int
pcap_init(unsigned int opts,char * errbuf)260 pcap_init(unsigned int opts, char *errbuf)
261 {
262           static int initialized;
263 
264           /*
265            * Don't allow multiple calls that set different modes; that
266            * may mean a library is initializing pcap in one mode and
267            * a program using that library, or another library used by
268            * that program, is initializing it in another mode.
269            */
270           switch (opts) {
271 
272           case PCAP_CHAR_ENC_LOCAL:
273                     /* Leave "UTF-8 mode" off. */
274                     if (initialized) {
275                               if (pcapint_utf_8_mode) {
276                                         snprintf(errbuf, PCAP_ERRBUF_SIZE,
277                                             "Multiple pcap_init calls with different character encodings");
278                                         return (PCAP_ERROR);
279                               }
280                     }
281                     break;
282 
283           case PCAP_CHAR_ENC_UTF_8:
284                     /* Turn on "UTF-8 mode". */
285                     if (initialized) {
286                               if (!pcapint_utf_8_mode) {
287                                         snprintf(errbuf, PCAP_ERRBUF_SIZE,
288                                             "Multiple pcap_init calls with different character encodings");
289                                         return (PCAP_ERROR);
290                               }
291                     }
292                     pcapint_utf_8_mode = 1;
293                     break;
294 
295           default:
296                     snprintf(errbuf, PCAP_ERRBUF_SIZE, "Unknown options specified");
297                     return (PCAP_ERROR);
298           }
299 
300           /*
301            * Turn the appropriate mode on for error messages; those routines
302            * are also used in rpcapd, which has no access to pcap's internal
303            * UTF-8 mode flag, so we have to call a routine to set its
304            * UTF-8 mode flag.
305            */
306           pcapint_fmt_set_encoding(opts);
307 
308           if (initialized) {
309                     /*
310                      * Nothing more to do; for example, on Windows, we've
311                      * already initialized Winsock.
312                      */
313                     return (0);
314           }
315 
316 #ifdef _WIN32
317           /*
318            * Now set up Winsock.
319            */
320           if (internal_wsockinit(errbuf) == -1) {
321                     /* Failed. */
322                     return (PCAP_ERROR);
323           }
324 #endif
325 
326           /*
327            * We're done.
328            */
329           initialized = 1;
330           pcapint_new_api = 1;
331           return (0);
332 }
333 
334 /*
335  * String containing the library version.
336  * Not explicitly exported via a header file - the right API to use
337  * is pcap_lib_version() - but some programs included it, so we
338  * provide it.
339  *
340  * We declare it here, right before defining it, to squelch any
341  * warnings we might get from compilers about the lack of a
342  * declaration.
343  */
344 PCAP_API char pcap_version[];
345 PCAP_API_DEF char pcap_version[] = PACKAGE_VERSION;
346 
347 static void
pcap_set_not_initialized_message(pcap_t * pcap)348 pcap_set_not_initialized_message(pcap_t *pcap)
349 {
350           if (pcap->activated) {
351                     /* A module probably forgot to set the function pointer */
352                     (void)snprintf(pcap->errbuf, sizeof(pcap->errbuf),
353                         "This operation isn't properly handled by that device");
354                     return;
355           }
356           /* in case the caller doesn't check for PCAP_ERROR_NOT_ACTIVATED */
357           (void)snprintf(pcap->errbuf, sizeof(pcap->errbuf),
358               "This handle hasn't been activated yet");
359 }
360 
361 static int
pcap_read_not_initialized(pcap_t * pcap,int cnt _U_,pcap_handler callback _U_,u_char * user _U_)362 pcap_read_not_initialized(pcap_t *pcap, int cnt _U_, pcap_handler callback _U_,
363     u_char *user _U_)
364 {
365           pcap_set_not_initialized_message(pcap);
366           /* this means 'not initialized' */
367           return (PCAP_ERROR_NOT_ACTIVATED);
368 }
369 
370 static int
pcap_inject_not_initialized(pcap_t * pcap,const void * buf _U_,size_t size _U_)371 pcap_inject_not_initialized(pcap_t *pcap, const void * buf _U_, size_t size _U_)
372 {
373           pcap_set_not_initialized_message(pcap);
374           /* this means 'not initialized' */
375           return (PCAP_ERROR_NOT_ACTIVATED);
376 }
377 
378 static int
pcap_setfilter_not_initialized(pcap_t * pcap,struct bpf_program * fp _U_)379 pcap_setfilter_not_initialized(pcap_t *pcap, struct bpf_program *fp _U_)
380 {
381           pcap_set_not_initialized_message(pcap);
382           /* this means 'not initialized' */
383           return (PCAP_ERROR_NOT_ACTIVATED);
384 }
385 
386 static int
pcap_setdirection_not_initialized(pcap_t * pcap,pcap_direction_t d _U_)387 pcap_setdirection_not_initialized(pcap_t *pcap, pcap_direction_t d _U_)
388 {
389           pcap_set_not_initialized_message(pcap);
390           /* this means 'not initialized' */
391           return (PCAP_ERROR_NOT_ACTIVATED);
392 }
393 
394 static int
pcap_set_datalink_not_initialized(pcap_t * pcap,int dlt _U_)395 pcap_set_datalink_not_initialized(pcap_t *pcap, int dlt _U_)
396 {
397           pcap_set_not_initialized_message(pcap);
398           /* this means 'not initialized' */
399           return (PCAP_ERROR_NOT_ACTIVATED);
400 }
401 
402 static int
pcap_getnonblock_not_initialized(pcap_t * pcap)403 pcap_getnonblock_not_initialized(pcap_t *pcap)
404 {
405           pcap_set_not_initialized_message(pcap);
406           /* this means 'not initialized' */
407           return (PCAP_ERROR_NOT_ACTIVATED);
408 }
409 
410 static int
pcap_stats_not_initialized(pcap_t * pcap,struct pcap_stat * ps _U_)411 pcap_stats_not_initialized(pcap_t *pcap, struct pcap_stat *ps _U_)
412 {
413           pcap_set_not_initialized_message(pcap);
414           /* this means 'not initialized' */
415           return (PCAP_ERROR_NOT_ACTIVATED);
416 }
417 
418 #ifdef _WIN32
419 static struct pcap_stat *
pcap_stats_ex_not_initialized(pcap_t * pcap,int * pcap_stat_size _U_)420 pcap_stats_ex_not_initialized(pcap_t *pcap, int *pcap_stat_size _U_)
421 {
422           pcap_set_not_initialized_message(pcap);
423           return (NULL);
424 }
425 
426 static int
pcap_setbuff_not_initialized(pcap_t * pcap,int dim _U_)427 pcap_setbuff_not_initialized(pcap_t *pcap, int dim _U_)
428 {
429           pcap_set_not_initialized_message(pcap);
430           /* this means 'not initialized' */
431           return (PCAP_ERROR_NOT_ACTIVATED);
432 }
433 
434 static int
pcap_setmode_not_initialized(pcap_t * pcap,int mode _U_)435 pcap_setmode_not_initialized(pcap_t *pcap, int mode _U_)
436 {
437           pcap_set_not_initialized_message(pcap);
438           /* this means 'not initialized' */
439           return (PCAP_ERROR_NOT_ACTIVATED);
440 }
441 
442 static int
pcap_setmintocopy_not_initialized(pcap_t * pcap,int size _U_)443 pcap_setmintocopy_not_initialized(pcap_t *pcap, int size _U_)
444 {
445           pcap_set_not_initialized_message(pcap);
446           /* this means 'not initialized' */
447           return (PCAP_ERROR_NOT_ACTIVATED);
448 }
449 
450 static HANDLE
pcap_getevent_not_initialized(pcap_t * pcap)451 pcap_getevent_not_initialized(pcap_t *pcap)
452 {
453           pcap_set_not_initialized_message(pcap);
454           return (INVALID_HANDLE_VALUE);
455 }
456 
457 static int
pcap_oid_get_request_not_initialized(pcap_t * pcap,bpf_u_int32 oid _U_,void * data _U_,size_t * lenp _U_)458 pcap_oid_get_request_not_initialized(pcap_t *pcap, bpf_u_int32 oid _U_,
459     void *data _U_, size_t *lenp _U_)
460 {
461           pcap_set_not_initialized_message(pcap);
462           return (PCAP_ERROR_NOT_ACTIVATED);
463 }
464 
465 static int
pcap_oid_set_request_not_initialized(pcap_t * pcap,bpf_u_int32 oid _U_,const void * data _U_,size_t * lenp _U_)466 pcap_oid_set_request_not_initialized(pcap_t *pcap, bpf_u_int32 oid _U_,
467     const void *data _U_, size_t *lenp _U_)
468 {
469           pcap_set_not_initialized_message(pcap);
470           return (PCAP_ERROR_NOT_ACTIVATED);
471 }
472 
473 static u_int
pcap_sendqueue_transmit_not_initialized(pcap_t * pcap,pcap_send_queue * queue _U_,int sync _U_)474 pcap_sendqueue_transmit_not_initialized(pcap_t *pcap, pcap_send_queue* queue _U_,
475     int sync _U_)
476 {
477           pcap_set_not_initialized_message(pcap);
478           return (0);
479 }
480 
481 static int
pcap_setuserbuffer_not_initialized(pcap_t * pcap,int size _U_)482 pcap_setuserbuffer_not_initialized(pcap_t *pcap, int size _U_)
483 {
484           pcap_set_not_initialized_message(pcap);
485           return (PCAP_ERROR_NOT_ACTIVATED);
486 }
487 
488 static int
pcap_live_dump_not_initialized(pcap_t * pcap,char * filename _U_,int maxsize _U_,int maxpacks _U_)489 pcap_live_dump_not_initialized(pcap_t *pcap, char *filename _U_, int maxsize _U_,
490     int maxpacks _U_)
491 {
492           pcap_set_not_initialized_message(pcap);
493           return (PCAP_ERROR_NOT_ACTIVATED);
494 }
495 
496 static int
pcap_live_dump_ended_not_initialized(pcap_t * pcap,int sync _U_)497 pcap_live_dump_ended_not_initialized(pcap_t *pcap, int sync _U_)
498 {
499           pcap_set_not_initialized_message(pcap);
500           return (PCAP_ERROR_NOT_ACTIVATED);
501 }
502 
503 static PAirpcapHandle
pcap_get_airpcap_handle_not_initialized(pcap_t * pcap)504 pcap_get_airpcap_handle_not_initialized(pcap_t *pcap)
505 {
506           pcap_set_not_initialized_message(pcap);
507           return (NULL);
508 }
509 #endif
510 
511 /*
512  * Returns 1 if rfmon mode can be set on the pcap_t, 0 if it can't,
513  * a PCAP_ERROR value on an error.
514  */
515 int
pcap_can_set_rfmon(pcap_t * p)516 pcap_can_set_rfmon(pcap_t *p)
517 {
518           return (p->can_set_rfmon_op(p));
519 }
520 
521 /*
522  * For systems where rfmon mode is never supported.
523  */
524 static int
pcap_cant_set_rfmon(pcap_t * p _U_)525 pcap_cant_set_rfmon(pcap_t *p _U_)
526 {
527           return (0);
528 }
529 
530 /*
531  * Sets *tstamp_typesp to point to an array 1 or more supported time stamp
532  * types; the return value is the number of supported time stamp types.
533  * The list should be freed by a call to pcap_free_tstamp_types() when
534  * you're done with it.
535  *
536  * A return value of 0 means "you don't get a choice of time stamp type",
537  * in which case *tstamp_typesp is set to null.
538  *
539  * PCAP_ERROR is returned on error.
540  */
541 int
pcap_list_tstamp_types(pcap_t * p,int ** tstamp_typesp)542 pcap_list_tstamp_types(pcap_t *p, int **tstamp_typesp)
543 {
544           if (p->tstamp_type_count == 0) {
545                     /*
546                      * We don't support multiple time stamp types.
547                      * That means the only type we support is PCAP_TSTAMP_HOST;
548                      * set up a list containing only that type.
549                      */
550                     *tstamp_typesp = (int*)malloc(sizeof(**tstamp_typesp));
551                     if (*tstamp_typesp == NULL) {
552                               pcapint_fmt_errmsg_for_errno(p->errbuf, sizeof(p->errbuf),
553                                   errno, "malloc");
554                               return (PCAP_ERROR);
555                     }
556                     **tstamp_typesp = PCAP_TSTAMP_HOST;
557                     return (1);
558           } else {
559                     *tstamp_typesp = (int*)calloc(p->tstamp_type_count,
560                                                         sizeof(**tstamp_typesp));
561                     if (*tstamp_typesp == NULL) {
562                               pcapint_fmt_errmsg_for_errno(p->errbuf, sizeof(p->errbuf),
563                                   errno, "malloc");
564                               return (PCAP_ERROR);
565                     }
566                     (void)memcpy(*tstamp_typesp, p->tstamp_type_list,
567                         sizeof(**tstamp_typesp) * p->tstamp_type_count);
568                     return (p->tstamp_type_count);
569           }
570 }
571 
572 /*
573  * In Windows, you might have a library built with one version of the
574  * C runtime library and an application built with another version of
575  * the C runtime library, which means that the library might use one
576  * version of malloc() and free() and the application might use another
577  * version of malloc() and free().  If so, that means something
578  * allocated by the library cannot be freed by the application, so we
579  * need to have a pcap_free_tstamp_types() routine to free up the list
580  * allocated by pcap_list_tstamp_types(), even though it's just a wrapper
581  * around free().
582  */
583 void
pcap_free_tstamp_types(int * tstamp_type_list)584 pcap_free_tstamp_types(int *tstamp_type_list)
585 {
586           free(tstamp_type_list);
587 }
588 
589 /*
590  * Default one-shot callback; overridden for capture types where the
591  * packet data cannot be guaranteed to be available after the callback
592  * returns, so that a copy must be made.
593  */
594 void
pcapint_oneshot(u_char * user,const struct pcap_pkthdr * h,const u_char * pkt)595 pcapint_oneshot(u_char *user, const struct pcap_pkthdr *h, const u_char *pkt)
596 {
597           struct oneshot_userdata *sp = (struct oneshot_userdata *)user;
598 
599           *sp->hdr = *h;
600           *sp->pkt = pkt;
601 }
602 
603 const u_char *
pcap_next(pcap_t * p,struct pcap_pkthdr * h)604 pcap_next(pcap_t *p, struct pcap_pkthdr *h)
605 {
606           struct oneshot_userdata s;
607           const u_char *pkt;
608 
609           s.hdr = h;
610           s.pkt = &pkt;
611           s.pd = p;
612           if (pcap_dispatch(p, 1, p->oneshot_callback, (u_char *)&s) <= 0)
613                     return (0);
614           return (pkt);
615 }
616 
617 int
pcap_next_ex(pcap_t * p,struct pcap_pkthdr ** pkt_header,const u_char ** pkt_data)618 pcap_next_ex(pcap_t *p, struct pcap_pkthdr **pkt_header,
619     const u_char **pkt_data)
620 {
621           struct oneshot_userdata s;
622 
623           s.hdr = &p->pcap_header;
624           s.pkt = pkt_data;
625           s.pd = p;
626 
627           /* Saves a pointer to the packet headers */
628           *pkt_header= &p->pcap_header;
629 
630           if (p->rfile != NULL) {
631                     int status;
632 
633                     /* We are on an offline capture */
634                     status = pcapint_offline_read(p, 1, p->oneshot_callback,
635                         (u_char *)&s);
636 
637                     /*
638                      * Return codes for pcapint_offline_read() are:
639                      *   -  0: EOF
640                      *   - -1: error
641                      *   - >0: OK - result is number of packets read, so
642                      *         it will be 1 in this case, as we've passed
643                      *         a maximum packet count of 1
644                      * The first one ('0') conflicts with the return code of
645                      * 0 from pcap_read() meaning "no packets arrived before
646                      * the timeout expired", so we map it to -2 so you can
647                      * distinguish between an EOF from a savefile and a
648                      * "no packets arrived before the timeout expired, try
649                      * again" from a live capture.
650                      */
651                     if (status == 0)
652                               return (-2);
653                     else
654                               return (status);
655           }
656 
657           /*
658            * Return codes for pcap_read() are:
659            *   -  0: timeout
660            *   - -1: error
661            *   - -2: loop was broken out of with pcap_breakloop()
662            *   - >0: OK, result is number of packets captured, so
663            *         it will be 1 in this case, as we've passed
664            *         a maximum packet count of 1
665            * The first one ('0') conflicts with the return code of 0 from
666            * pcapint_offline_read() meaning "end of file".
667           */
668           return (p->read_op(p, 1, p->oneshot_callback, (u_char *)&s));
669 }
670 
671 /*
672  * Implementation of a pcap_if_list_t.
673  */
674 struct pcap_if_list {
675           pcap_if_t *beginning;
676 };
677 
678 static struct capture_source_type {
679           int (*findalldevs_op)(pcap_if_list_t *, char *);
680           pcap_t *(*create_op)(const char *, char *, int *);
681 } capture_source_types[] = {
682 #ifdef HAVE_DAG_API
683           { dag_findalldevs, dag_create },
684 #endif
685 #ifdef HAVE_SEPTEL_API
686           { septel_findalldevs, septel_create },
687 #endif
688 #ifdef HAVE_SNF_API
689           { snf_findalldevs, snf_create },
690 #endif
691 #ifdef HAVE_TC_API
692           { TcFindAllDevs, TcCreate },
693 #endif
694 #ifdef PCAP_SUPPORT_BT
695           { bt_findalldevs, bt_create },
696 #endif
697 #ifdef PCAP_SUPPORT_BT_MONITOR
698           { bt_monitor_findalldevs, bt_monitor_create },
699 #endif
700 #ifdef PCAP_SUPPORT_LINUX_USBMON
701           { usb_findalldevs, usb_create },
702 #endif
703 #ifdef PCAP_SUPPORT_NETFILTER
704           { netfilter_findalldevs, netfilter_create },
705 #endif
706 #ifdef PCAP_SUPPORT_NETMAP
707           { pcap_netmap_findalldevs, pcap_netmap_create },
708 #endif
709 #ifdef PCAP_SUPPORT_DBUS
710           { dbus_findalldevs, dbus_create },
711 #endif
712 #ifdef PCAP_SUPPORT_RDMASNIFF
713           { rdmasniff_findalldevs, rdmasniff_create },
714 #endif
715 #ifdef PCAP_SUPPORT_DPDK
716           { pcap_dpdk_findalldevs, pcap_dpdk_create },
717 #endif
718 #ifdef HAVE_AIRPCAP_API
719           { airpcap_findalldevs, airpcap_create },
720 #endif
721           { NULL, NULL }
722 };
723 
724 /*
725  * Get a list of all capture sources that are up and that we can open.
726  * Returns -1 on error, 0 otherwise.
727  * The list, as returned through "alldevsp", may be null if no interfaces
728  * were up and could be opened.
729  */
730 int
pcap_findalldevs(pcap_if_t ** alldevsp,char * errbuf)731 pcap_findalldevs(pcap_if_t **alldevsp, char *errbuf)
732 {
733           size_t i;
734           pcap_if_list_t devlist;
735 
736           /*
737            * Find all the local network interfaces on which we
738            * can capture.
739            */
740           devlist.beginning = NULL;
741           if (pcapint_platform_finddevs(&devlist, errbuf) == -1) {
742                     /*
743                      * Failed - free all of the entries we were given
744                      * before we failed.
745                      */
746                     if (devlist.beginning != NULL)
747                               pcap_freealldevs(devlist.beginning);
748                     *alldevsp = NULL;
749                     return (-1);
750           }
751 
752           /*
753            * Ask each of the non-local-network-interface capture
754            * source types what interfaces they have.
755            */
756           for (i = 0; capture_source_types[i].findalldevs_op != NULL; i++) {
757                     if (capture_source_types[i].findalldevs_op(&devlist, errbuf) == -1) {
758                               /*
759                                * We had an error; free the list we've been
760                                * constructing.
761                                */
762                               if (devlist.beginning != NULL)
763                                         pcap_freealldevs(devlist.beginning);
764                               *alldevsp = NULL;
765                               return (-1);
766                     }
767           }
768 
769           /*
770            * Return the first entry of the list of all devices.
771            */
772           *alldevsp = devlist.beginning;
773           return (0);
774 }
775 
776 static struct sockaddr *
dup_sockaddr(struct sockaddr * sa,size_t sa_length)777 dup_sockaddr(struct sockaddr *sa, size_t sa_length)
778 {
779           struct sockaddr *newsa;
780 
781           if ((newsa = malloc(sa_length)) == NULL)
782                     return (NULL);
783           return (memcpy(newsa, sa, sa_length));
784 }
785 
786 /*
787  * Construct a "figure of merit" for an interface, for use when sorting
788  * the list of interfaces, in which interfaces that are up are superior
789  * to interfaces that aren't up, interfaces that are up and running are
790  * superior to interfaces that are up but not running, and non-loopback
791  * interfaces that are up and running are superior to loopback interfaces,
792  * and interfaces with the same flags have a figure of merit that's higher
793  * the lower the instance number.
794  *
795  * The goal is to try to put the interfaces most likely to be useful for
796  * capture at the beginning of the list.
797  *
798  * The figure of merit, which is lower the "better" the interface is,
799  * has the uppermost bit set if the interface isn't running, the bit
800  * below that set if the interface isn't up, the bit below that
801  * set if the interface is a loopback interface, and the bit below
802  * that set if it's the "any" interface.
803  *
804  * Note: we don't sort by unit number because 1) not all interfaces have
805  * a unit number (systemd, for example, might assign interface names
806  * based on the interface's MAC address or on the physical location of
807  * the adapter's connector), and 2) if the name does end with a simple
808  * unit number, it's not a global property of the interface, it's only
809  * useful as a sort key for device names with the same prefix, so xyz0
810  * shouldn't necessarily sort before abc2.  This means that interfaces
811  * with the same figure of merit will be sorted by the order in which
812  * the mechanism from which we're getting the interfaces supplies them.
813  */
814 static u_int
get_figure_of_merit(pcap_if_t * dev)815 get_figure_of_merit(pcap_if_t *dev)
816 {
817           u_int n;
818 
819           n = 0;
820           if (!(dev->flags & PCAP_IF_RUNNING))
821                     n |= 0x80000000;
822           if (!(dev->flags & PCAP_IF_UP))
823                     n |= 0x40000000;
824 
825           /*
826            * Give non-wireless interfaces that aren't disconnected a better
827            * figure of merit than interfaces that are disconnected, as
828            * "disconnected" should indicate that the interface isn't
829            * plugged into a network and thus won't give you any traffic.
830            *
831            * For wireless interfaces, it means "associated with a network",
832            * which we presume not to necessarily prevent capture, as you
833            * might run the adapter in some flavor of monitor mode.
834            */
835           if (!(dev->flags & PCAP_IF_WIRELESS) &&
836               (dev->flags & PCAP_IF_CONNECTION_STATUS) == PCAP_IF_CONNECTION_STATUS_DISCONNECTED)
837                     n |= 0x20000000;
838 
839           /*
840            * Sort loopback devices after non-loopback devices, *except* for
841            * disconnected devices.
842            */
843           if (dev->flags & PCAP_IF_LOOPBACK)
844                     n |= 0x10000000;
845 
846           /*
847            * Sort the "any" device before loopback and disconnected devices,
848            * but after all other devices.
849            */
850           if (strcmp(dev->name, "any") == 0)
851                     n |= 0x08000000;
852 
853           return (n);
854 }
855 
856 #ifndef _WIN32
857 /*
858  * Try to get a description for a given device.
859  * Returns a malloced description if it could and NULL if it couldn't.
860  *
861  * XXX - on FreeBSDs that support it, should it get the sysctl named
862  * "dev.{adapter family name}.{adapter unit}.%desc" to get a description
863  * of the adapter?  Note that "dev.an.0.%desc" is "Aironet PC4500/PC4800"
864  * with my Cisco 350 card, so the name isn't entirely descriptive.  The
865  * "dev.an.0.%pnpinfo" has a better description, although one might argue
866  * that the problem is really a driver bug - if it can find out that it's
867  * a Cisco 340 or 350, rather than an old Aironet card, it should use
868  * that in the description.
869  *
870  * Do NetBSD, DragonflyBSD, or OpenBSD support this as well?  FreeBSD
871  * and OpenBSD let you get a description, but it's not generated by the OS,
872  * it's set with another ioctl that ifconfig supports; we use that to get
873  * a description in FreeBSD and OpenBSD, but if there is no such
874  * description available, it still might be nice to get some description
875  * string based on the device type or something such as that.
876  *
877  * In macOS, the System Configuration framework can apparently return
878  * names in 10.4 and later.
879  *
880  * It also appears that freedesktop.org's HAL offers an "info.product"
881  * string, but the HAL specification says it "should not be used in any
882  * UI" and "subsystem/capability specific properties" should be used
883  * instead and, in any case, I think HAL is being deprecated in
884  * favor of other stuff such as DeviceKit.  DeviceKit doesn't appear
885  * to have any obvious product information for devices, but maybe
886  * I haven't looked hard enough.
887  *
888  * Using the System Configuration framework, or HAL, or DeviceKit, or
889  * whatever, would require that libpcap applications be linked with
890  * the frameworks/libraries in question.  That shouldn't be a problem
891  * for programs linking with the shared version of libpcap (unless
892  * you're running on AIX - which I think is the only UN*X that doesn't
893  * support linking a shared library with other libraries on which it
894  * depends, and having an executable linked only with the first shared
895  * library automatically pick up the other libraries when started -
896  * and using HAL or whatever).  Programs linked with the static
897  * version of libpcap would have to use pcap-config with the --static
898  * flag in order to get the right linker flags in order to pick up
899  * the additional libraries/frameworks; those programs need that anyway
900  * for libpcap 1.1 and beyond on Linux, as, by default, it requires
901  * -lnl.
902  *
903  * Do any other UN*Xes, or desktop environments support getting a
904  * description?
905  */
906 static char *
907 #ifdef SIOCGIFDESCR
get_if_description(const char * name)908 get_if_description(const char *name)
909 {
910           char *description = NULL;
911           int s;
912           struct ifreq ifrdesc;
913 #ifndef IFDESCRSIZE
914           size_t descrlen = 64;
915 #else
916           size_t descrlen = IFDESCRSIZE;
917 #endif /* IFDESCRSIZE */
918 
919           /*
920            * Get the description for the interface.
921            */
922           memset(&ifrdesc, 0, sizeof ifrdesc);
923           pcapint_strlcpy(ifrdesc.ifr_name, name, sizeof ifrdesc.ifr_name);
924           s = socket(AF_INET, SOCK_DGRAM, 0);
925           if (s >= 0) {
926 #ifdef __FreeBSD__
927                     /*
928                      * On FreeBSD, if the buffer isn't big enough for the
929                      * description, the ioctl succeeds, but the description
930                      * isn't copied, ifr_buffer.length is set to the description
931                      * length, and ifr_buffer.buffer is set to NULL.
932                      */
933                     for (;;) {
934                               free(description);
935                               if ((description = malloc(descrlen)) != NULL) {
936                                         ifrdesc.ifr_buffer.buffer = description;
937                                         ifrdesc.ifr_buffer.length = descrlen;
938                                         if (ioctl(s, SIOCGIFDESCR, &ifrdesc) == 0) {
939                                                   if (ifrdesc.ifr_buffer.buffer ==
940                                                       description)
941                                                             break;
942                                                   else
943                                                             descrlen = ifrdesc.ifr_buffer.length;
944                                         } else {
945                                                   /*
946                                                    * Failed to get interface description.
947                                                    */
948                                                   free(description);
949                                                   description = NULL;
950                                                   break;
951                                         }
952                               } else
953                                         break;
954                     }
955 #else /* __FreeBSD__ */
956                     /*
957                      * The only other OS that currently supports
958                      * SIOCGIFDESCR is OpenBSD, and it has no way
959                      * to get the description length - it's clamped
960                      * to a maximum of IFDESCRSIZE.
961                      */
962                     if ((description = malloc(descrlen)) != NULL) {
963                               ifrdesc.ifr_data = (caddr_t)description;
964                               if (ioctl(s, SIOCGIFDESCR, &ifrdesc) != 0) {
965                                         /*
966                                          * Failed to get interface description.
967                                          */
968                                         free(description);
969                                         description = NULL;
970                               }
971                     }
972 #endif /* __FreeBSD__ */
973                     close(s);
974                     if (description != NULL && description[0] == '\0') {
975                               /*
976                                * Description is empty, so discard it.
977                                */
978                               free(description);
979                               description = NULL;
980                     }
981           }
982 
983 #ifdef __FreeBSD__
984           /*
985            * For FreeBSD, if we didn't get a description, and this is
986            * a device with a name of the form usbusN, label it as a USB
987            * bus.
988            */
989           if (description == NULL) {
990                     if (strncmp(name, "usbus", 5) == 0) {
991                               /*
992                                * OK, it begins with "usbus".
993                                */
994                               long busnum;
995                               char *p;
996 
997                               errno = 0;
998                               busnum = strtol(name + 5, &p, 10);
999                               if (errno == 0 && p != name + 5 && *p == '\0' &&
1000                                   busnum >= 0 && busnum <= INT_MAX) {
1001                                         /*
1002                                          * OK, it's a valid number that's not
1003                                          * bigger than INT_MAX.  Construct
1004                                          * a description from it.
1005                                          * (If that fails, we don't worry about
1006                                          * it, we just return NULL.)
1007                                          */
1008                                         if (pcapint_asprintf(&description,
1009                                             "USB bus number %ld", busnum) == -1) {
1010                                                   /* Failed. */
1011                                                   description = NULL;
1012                                         }
1013                               }
1014                     }
1015           }
1016 #endif
1017           return (description);
1018 #else /* SIOCGIFDESCR */
1019 get_if_description(const char *name _U_)
1020 {
1021           return (NULL);
1022 #endif /* SIOCGIFDESCR */
1023 }
1024 
1025 /*
1026  * Look for a given device in the specified list of devices.
1027  *
1028  * If we find it, return a pointer to its entry.
1029  *
1030  * If we don't find it, attempt to add an entry for it, with the specified
1031  * IFF_ flags and description, and, if that succeeds, return a pointer to
1032  * the new entry, otherwise return NULL and set errbuf to an error message.
1033  */
1034 pcap_if_t *
1035 pcapint_find_or_add_if(pcap_if_list_t *devlistp, const char *name,
1036     uint64_t if_flags, get_if_flags_func get_flags_func, char *errbuf)
1037 {
1038           bpf_u_int32 pcap_flags;
1039 
1040           /*
1041            * Convert IFF_ flags to pcap flags.
1042            */
1043           pcap_flags = 0;
1044 #ifdef IFF_LOOPBACK
1045           if (if_flags & IFF_LOOPBACK)
1046                     pcap_flags |= PCAP_IF_LOOPBACK;
1047 #else
1048           /*
1049            * We don't have IFF_LOOPBACK, so look at the device name to
1050            * see if it looks like a loopback device.
1051            */
1052           if (name[0] == 'l' && name[1] == 'o' &&
1053               (PCAP_ISDIGIT(name[2]) || name[2] == '\0'))
1054                     pcap_flags |= PCAP_IF_LOOPBACK;
1055 #endif
1056 #ifdef IFF_UP
1057           if (if_flags & IFF_UP)
1058                     pcap_flags |= PCAP_IF_UP;
1059 #endif
1060 #ifdef IFF_RUNNING
1061           if (if_flags & IFF_RUNNING)
1062                     pcap_flags |= PCAP_IF_RUNNING;
1063 #endif
1064 
1065           /*
1066            * Attempt to find an entry for this device; if we don't find one,
1067            * attempt to add one.
1068            */
1069           return (pcapint_find_or_add_dev(devlistp, name, pcap_flags,
1070               get_flags_func, get_if_description(name), errbuf));
1071 }
1072 
1073 /*
1074  * Look for a given device in the specified list of devices.
1075  *
1076  * If we find it, then, if the specified address isn't null, add it to
1077  * the list of addresses for the device and return 0.
1078  *
1079  * If we don't find it, attempt to add an entry for it, with the specified
1080  * IFF_ flags and description, and, if that succeeds, add the specified
1081  * address to its list of addresses if that address is non-null, and
1082  * return 0, otherwise return -1 and set errbuf to an error message.
1083  *
1084  * (We can get called with a null address because we might get a list
1085  * of interface name/address combinations from the underlying OS, with
1086  * the address being absent in some cases, rather than a list of
1087  * interfaces with each interface having a list of addresses, so this
1088  * call may be the only call made to add to the list, and we want to
1089  * add interfaces even if they have no addresses.)
1090  */
1091 int
1092 pcapint_add_addr_to_if(pcap_if_list_t *devlistp, const char *name,
1093     uint64_t if_flags, get_if_flags_func get_flags_func,
1094     struct sockaddr *addr, size_t addr_size,
1095     struct sockaddr *netmask, size_t netmask_size,
1096     struct sockaddr *broadaddr, size_t broadaddr_size,
1097     struct sockaddr *dstaddr, size_t dstaddr_size,
1098     char *errbuf)
1099 {
1100           pcap_if_t *curdev;
1101 
1102           /*
1103            * Check whether the device exists and, if not, add it.
1104            */
1105           curdev = pcapint_find_or_add_if(devlistp, name, if_flags, get_flags_func,
1106               errbuf);
1107           if (curdev == NULL) {
1108                     /*
1109                      * Error - give up.
1110                      */
1111                     return (-1);
1112           }
1113 
1114           if (addr == NULL) {
1115                     /*
1116                      * There's no address to add; this entry just meant
1117                      * "here's a new interface".
1118                      */
1119                     return (0);
1120           }
1121 
1122           /*
1123            * "curdev" is an entry for this interface, and we have an
1124            * address for it; add an entry for that address to the
1125            * interface's list of addresses.
1126            */
1127           return (pcapint_add_addr_to_dev(curdev, addr, addr_size, netmask,
1128               netmask_size, broadaddr, broadaddr_size, dstaddr,
1129               dstaddr_size, errbuf));
1130 }
1131 #endif /* _WIN32 */
1132 
1133 /*
1134  * Add an entry to the list of addresses for an interface.
1135  * "curdev" is the entry for that interface.
1136  */
1137 int
1138 pcapint_add_addr_to_dev(pcap_if_t *curdev,
1139     struct sockaddr *addr, size_t addr_size,
1140     struct sockaddr *netmask, size_t netmask_size,
1141     struct sockaddr *broadaddr, size_t broadaddr_size,
1142     struct sockaddr *dstaddr, size_t dstaddr_size,
1143     char *errbuf)
1144 {
1145           pcap_addr_t *curaddr, *prevaddr, *nextaddr;
1146 
1147           /*
1148            * Allocate the new entry and fill it in.
1149            */
1150           curaddr = (pcap_addr_t *)malloc(sizeof(pcap_addr_t));
1151           if (curaddr == NULL) {
1152                     pcapint_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
1153                         errno, "malloc");
1154                     return (-1);
1155           }
1156 
1157           curaddr->next = NULL;
1158           if (addr != NULL && addr_size != 0) {
1159                     curaddr->addr = (struct sockaddr *)dup_sockaddr(addr, addr_size);
1160                     if (curaddr->addr == NULL) {
1161                               pcapint_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
1162                                   errno, "malloc");
1163                               free(curaddr);
1164                               return (-1);
1165                     }
1166           } else
1167                     curaddr->addr = NULL;
1168 
1169           if (netmask != NULL && netmask_size != 0) {
1170                     curaddr->netmask = (struct sockaddr *)dup_sockaddr(netmask, netmask_size);
1171                     if (curaddr->netmask == NULL) {
1172                               pcapint_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
1173                                   errno, "malloc");
1174                               if (curaddr->addr != NULL)
1175                                         free(curaddr->addr);
1176                               free(curaddr);
1177                               return (-1);
1178                     }
1179           } else
1180                     curaddr->netmask = NULL;
1181 
1182           if (broadaddr != NULL && broadaddr_size != 0) {
1183                     curaddr->broadaddr = (struct sockaddr *)dup_sockaddr(broadaddr, broadaddr_size);
1184                     if (curaddr->broadaddr == NULL) {
1185                               pcapint_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
1186                                   errno, "malloc");
1187                               if (curaddr->netmask != NULL)
1188                                         free(curaddr->netmask);
1189                               if (curaddr->addr != NULL)
1190                                         free(curaddr->addr);
1191                               free(curaddr);
1192                               return (-1);
1193                     }
1194           } else
1195                     curaddr->broadaddr = NULL;
1196 
1197           if (dstaddr != NULL && dstaddr_size != 0) {
1198                     curaddr->dstaddr = (struct sockaddr *)dup_sockaddr(dstaddr, dstaddr_size);
1199                     if (curaddr->dstaddr == NULL) {
1200                               pcapint_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
1201                                   errno, "malloc");
1202                               if (curaddr->broadaddr != NULL)
1203                                         free(curaddr->broadaddr);
1204                               if (curaddr->netmask != NULL)
1205                                         free(curaddr->netmask);
1206                               if (curaddr->addr != NULL)
1207                                         free(curaddr->addr);
1208                               free(curaddr);
1209                               return (-1);
1210                     }
1211           } else
1212                     curaddr->dstaddr = NULL;
1213 
1214           /*
1215            * Find the end of the list of addresses.
1216            */
1217           for (prevaddr = curdev->addresses; prevaddr != NULL; prevaddr = nextaddr) {
1218                     nextaddr = prevaddr->next;
1219                     if (nextaddr == NULL) {
1220                               /*
1221                                * This is the end of the list.
1222                                */
1223                               break;
1224                     }
1225           }
1226 
1227           if (prevaddr == NULL) {
1228                     /*
1229                      * The list was empty; this is the first member.
1230                      */
1231                     curdev->addresses = curaddr;
1232           } else {
1233                     /*
1234                      * "prevaddr" is the last member of the list; append
1235                      * this member to it.
1236                      */
1237                     prevaddr->next = curaddr;
1238           }
1239 
1240           return (0);
1241 }
1242 
1243 /*
1244  * Look for a given device in the specified list of devices.
1245  *
1246  * If we find it, return 0 and set *curdev_ret to point to it.
1247  *
1248  * If we don't find it, attempt to add an entry for it, with the specified
1249  * flags and description, and, if that succeeds, return 0, otherwise
1250  * return -1 and set errbuf to an error message.
1251  */
1252 pcap_if_t *
1253 pcapint_find_or_add_dev(pcap_if_list_t *devlistp, const char *name, bpf_u_int32 flags,
1254     get_if_flags_func get_flags_func, const char *description, char *errbuf)
1255 {
1256           pcap_if_t *curdev;
1257 
1258           /*
1259            * Is there already an entry in the list for this device?
1260            */
1261           curdev = pcapint_find_dev(devlistp, name);
1262           if (curdev != NULL) {
1263                     /*
1264                      * Yes, return it.
1265                      */
1266                     return (curdev);
1267           }
1268 
1269           /*
1270            * No, we didn't find it.
1271            */
1272 
1273           /*
1274            * Try to get additional flags for the device.
1275            */
1276           if ((*get_flags_func)(name, &flags, errbuf) == -1) {
1277                     /*
1278                      * Failed.
1279                      */
1280                     return (NULL);
1281           }
1282 
1283           /*
1284            * Now, try to add it to the list of devices.
1285            */
1286           return (pcapint_add_dev(devlistp, name, flags, description, errbuf));
1287 }
1288 
1289 /*
1290  * Look for a given device in the specified list of devices, and return
1291  * the entry for it if we find it or NULL if we don't.
1292  */
1293 pcap_if_t *
1294 pcapint_find_dev(pcap_if_list_t *devlistp, const char *name)
1295 {
1296           pcap_if_t *curdev;
1297 
1298           /*
1299            * Is there an entry in the list for this device?
1300            */
1301           for (curdev = devlistp->beginning; curdev != NULL;
1302               curdev = curdev->next) {
1303                     if (strcmp(name, curdev->name) == 0) {
1304                               /*
1305                                * We found it, so, yes, there is.  No need to
1306                                * add it.  Provide the entry we found to our
1307                                * caller.
1308                                */
1309                               return (curdev);
1310                     }
1311           }
1312 
1313           /*
1314            * No.
1315            */
1316           return (NULL);
1317 }
1318 
1319 /*
1320  * Attempt to add an entry for a device, with the specified flags
1321  * and description, and, if that succeeds, return 0 and return a pointer
1322  * to the new entry, otherwise return NULL and set errbuf to an error
1323  * message.
1324  *
1325  * If we weren't given a description, try to get one.
1326  */
1327 pcap_if_t *
1328 pcapint_add_dev(pcap_if_list_t *devlistp, const char *name, bpf_u_int32 flags,
1329     const char *description, char *errbuf)
1330 {
1331           pcap_if_t *curdev, *prevdev, *nextdev;
1332           u_int this_figure_of_merit, nextdev_figure_of_merit;
1333 
1334           curdev = malloc(sizeof(pcap_if_t));
1335           if (curdev == NULL) {
1336                     pcapint_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
1337                         errno, "malloc");
1338                     return (NULL);
1339           }
1340 
1341           /*
1342            * Fill in the entry.
1343            */
1344           curdev->next = NULL;
1345           curdev->name = strdup(name);
1346           if (curdev->name == NULL) {
1347                     pcapint_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
1348                         errno, "malloc");
1349                     free(curdev);
1350                     return (NULL);
1351           }
1352           if (description == NULL) {
1353                     /*
1354                      * We weren't handed a description for the interface.
1355                      */
1356                     curdev->description = NULL;
1357           } else {
1358                     /*
1359                      * We were handed a description; make a copy.
1360                      */
1361                     curdev->description = strdup(description);
1362                     if (curdev->description == NULL) {
1363                               pcapint_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
1364                                   errno, "malloc");
1365                               free(curdev->name);
1366                               free(curdev);
1367                               return (NULL);
1368                     }
1369           }
1370           curdev->addresses = NULL;     /* list starts out as empty */
1371           curdev->flags = flags;
1372 
1373           /*
1374            * Add it to the list, in the appropriate location.
1375            * First, get the "figure of merit" for this interface.
1376            */
1377           this_figure_of_merit = get_figure_of_merit(curdev);
1378 
1379           /*
1380            * Now look for the last interface with an figure of merit
1381            * less than or equal to the new interface's figure of merit.
1382            *
1383            * We start with "prevdev" being NULL, meaning we're before
1384            * the first element in the list.
1385            */
1386           prevdev = NULL;
1387           for (;;) {
1388                     /*
1389                      * Get the interface after this one.
1390                      */
1391                     if (prevdev == NULL) {
1392                               /*
1393                                * The next element is the first element.
1394                                */
1395                               nextdev = devlistp->beginning;
1396                     } else
1397                               nextdev = prevdev->next;
1398 
1399                     /*
1400                      * Are we at the end of the list?
1401                      */
1402                     if (nextdev == NULL) {
1403                               /*
1404                                * Yes - we have to put the new entry after "prevdev".
1405                                */
1406                               break;
1407                     }
1408 
1409                     /*
1410                      * Is the new interface's figure of merit less
1411                      * than the next interface's figure of merit,
1412                      * meaning that the new interface is better
1413                      * than the next interface?
1414                      */
1415                     nextdev_figure_of_merit = get_figure_of_merit(nextdev);
1416                     if (this_figure_of_merit < nextdev_figure_of_merit) {
1417                               /*
1418                                * Yes - we should put the new entry
1419                                * before "nextdev", i.e. after "prevdev".
1420                                */
1421                               break;
1422                     }
1423 
1424                     prevdev = nextdev;
1425           }
1426 
1427           /*
1428            * Insert before "nextdev".
1429            */
1430           curdev->next = nextdev;
1431 
1432           /*
1433            * Insert after "prevdev" - unless "prevdev" is null,
1434            * in which case this is the first interface.
1435            */
1436           if (prevdev == NULL) {
1437                     /*
1438                      * This is the first interface.  Make it
1439                      * the first element in the list of devices.
1440                      */
1441                     devlistp->beginning = curdev;
1442           } else
1443                     prevdev->next = curdev;
1444           return (curdev);
1445 }
1446 
1447 /*
1448  * Add an entry for the "any" device.
1449  */
1450 pcap_if_t *
1451 pcap_add_any_dev(pcap_if_list_t *devlistp, char *errbuf)
1452 {
1453           static const char any_descr[] = "Pseudo-device that captures on all interfaces";
1454 
1455           /*
1456            * As it refers to all network devices, not to any particular
1457            * network device, the notion of "connected" vs. "disconnected"
1458            * doesn't apply to the "any" device.
1459            */
1460           return pcapint_add_dev(devlistp, "any",
1461               PCAP_IF_UP|PCAP_IF_RUNNING|PCAP_IF_CONNECTION_STATUS_NOT_APPLICABLE,
1462               any_descr, errbuf);
1463 }
1464 
1465 /*
1466  * Free a list of interfaces.
1467  */
1468 void
1469 pcap_freealldevs(pcap_if_t *alldevs)
1470 {
1471           pcap_if_t *curdev, *nextdev;
1472           pcap_addr_t *curaddr, *nextaddr;
1473 
1474           for (curdev = alldevs; curdev != NULL; curdev = nextdev) {
1475                     nextdev = curdev->next;
1476 
1477                     /*
1478                      * Free all addresses.
1479                      */
1480                     for (curaddr = curdev->addresses; curaddr != NULL; curaddr = nextaddr) {
1481                               nextaddr = curaddr->next;
1482                               if (curaddr->addr)
1483                                         free(curaddr->addr);
1484                               if (curaddr->netmask)
1485                                         free(curaddr->netmask);
1486                               if (curaddr->broadaddr)
1487                                         free(curaddr->broadaddr);
1488                               if (curaddr->dstaddr)
1489                                         free(curaddr->dstaddr);
1490                               free(curaddr);
1491                     }
1492 
1493                     /*
1494                      * Free the name string.
1495                      */
1496                     free(curdev->name);
1497 
1498                     /*
1499                      * Free the description string, if any.
1500                      */
1501                     if (curdev->description != NULL)
1502                               free(curdev->description);
1503 
1504                     /*
1505                      * Free the interface.
1506                      */
1507                     free(curdev);
1508           }
1509 }
1510 
1511 /*
1512  * pcap-npf.c has its own pcap_lookupdev(), for compatibility reasons, as
1513  * it actually returns the names of all interfaces, with a NUL separator
1514  * between them; some callers may depend on that.
1515  *
1516  * MS-DOS has its own pcap_lookupdev(), but that might be useful only
1517  * as an optimization.
1518  *
1519  * In all other cases, we just use pcap_findalldevs() to get a list of
1520  * devices, and pick from that list.
1521  */
1522 #if !defined(HAVE_PACKET32) && !defined(MSDOS)
1523 /*
1524  * Return the name of a network interface attached to the system, or NULL
1525  * if none can be found.  The interface must be configured up; the
1526  * lowest unit number is preferred; loopback is ignored.
1527  */
1528 char *
1529 pcap_lookupdev(char *errbuf)
1530 {
1531           pcap_if_t *alldevs;
1532 #ifdef _WIN32
1533   /*
1534    * Windows - use the same size as the old WinPcap 3.1 code.
1535    * XXX - this is probably bigger than it needs to be.
1536    */
1537   #define IF_NAMESIZE 8192
1538 #else
1539   /*
1540    * UN*X - use the system's interface name size.
1541    * XXX - that might not be large enough for capture devices
1542    * that aren't regular network interfaces.
1543    */
1544   /* for old BSD systems, including bsdi3 */
1545   #ifndef IF_NAMESIZE
1546   #define IF_NAMESIZE IFNAMSIZ
1547   #endif
1548 #endif
1549           static char device[IF_NAMESIZE + 1];
1550           char *ret;
1551 
1552           /*
1553            * We disable this in "new API" mode, because 1) in WinPcap/Npcap,
1554            * it may return UTF-16 strings, for backwards-compatibility
1555            * reasons, and we're also disabling the hack to make that work,
1556            * for not-going-past-the-end-of-a-string reasons, and 2) we
1557            * want its behavior to be consistent.
1558            *
1559            * In addition, it's not thread-safe, so we've marked it as
1560            * deprecated.
1561            */
1562           if (pcapint_new_api) {
1563                     snprintf(errbuf, PCAP_ERRBUF_SIZE,
1564                         "pcap_lookupdev() is deprecated and is not supported in programs calling pcap_init()");
1565                     return (NULL);
1566           }
1567 
1568           if (pcap_findalldevs(&alldevs, errbuf) == -1)
1569                     return (NULL);
1570 
1571           if (alldevs == NULL || (alldevs->flags & PCAP_IF_LOOPBACK)) {
1572                     /*
1573                      * There are no devices on the list, or the first device
1574                      * on the list is a loopback device, which means there
1575                      * are no non-loopback devices on the list.  This means
1576                      * we can't return any device.
1577                      *
1578                      * XXX - why not return a loopback device?  If we can't
1579                      * capture on it, it won't be on the list, and if it's
1580                      * on the list, there aren't any non-loopback devices,
1581                      * so why not just supply it as the default device?
1582                      */
1583                     (void)pcapint_strlcpy(errbuf, "no suitable device found",
1584                         PCAP_ERRBUF_SIZE);
1585                     ret = NULL;
1586           } else {
1587                     /*
1588                      * Return the name of the first device on the list.
1589                      */
1590                     (void)pcapint_strlcpy(device, alldevs->name, sizeof(device));
1591                     ret = device;
1592           }
1593 
1594           pcap_freealldevs(alldevs);
1595           return (ret);
1596 }
1597 #endif /* !defined(HAVE_PACKET32) && !defined(MSDOS) */
1598 
1599 #if !defined(_WIN32) && !defined(MSDOS)
1600 /*
1601  * We don't just fetch the entire list of devices, search for the
1602  * particular device, and use its first IPv4 address, as that's too
1603  * much work to get just one device's netmask.
1604  *
1605  * If we had an API to get attributes for a given device, we could
1606  * use that.
1607  */
1608 int
1609 pcap_lookupnet(const char *device, bpf_u_int32 *netp, bpf_u_int32 *maskp,
1610     char *errbuf)
1611 {
1612           register int fd;
1613           register struct sockaddr_in *sin4;
1614           struct ifreq ifr;
1615 
1616           /*
1617            * The pseudo-device "any" listens on all interfaces and therefore
1618            * has the network address and -mask "0.0.0.0" therefore catching
1619            * all traffic. Using NULL for the interface is the same as "any".
1620            */
1621           if (!device || strcmp(device, "any") == 0
1622 #ifdef HAVE_DAG_API
1623               || strstr(device, "dag") != NULL
1624 #endif
1625 #ifdef HAVE_SEPTEL_API
1626               || strstr(device, "septel") != NULL
1627 #endif
1628 #ifdef PCAP_SUPPORT_BT
1629               || strstr(device, "bluetooth") != NULL
1630 #endif
1631 #ifdef PCAP_SUPPORT_LINUX_USBMON
1632               || strstr(device, "usbmon") != NULL
1633 #endif
1634 #ifdef HAVE_SNF_API
1635               || strstr(device, "snf") != NULL
1636 #endif
1637 #ifdef PCAP_SUPPORT_NETMAP
1638               || strncmp(device, "netmap:", 7) == 0
1639               || strncmp(device, "vale", 4) == 0
1640 #endif
1641 #ifdef PCAP_SUPPORT_DPDK
1642               || strncmp(device, "dpdk:", 5) == 0
1643 #endif
1644               ) {
1645                     *netp = *maskp = 0;
1646                     return 0;
1647           }
1648 
1649           fd = socket(AF_INET, SOCK_DGRAM, 0);
1650           if (fd < 0) {
1651                     pcapint_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
1652                         errno, "socket");
1653                     return (-1);
1654           }
1655           memset(&ifr, 0, sizeof(ifr));
1656 #ifdef __linux__
1657           /* XXX Work around Linux kernel bug */
1658           ifr.ifr_addr.sa_family = AF_INET;
1659 #endif
1660           (void)pcapint_strlcpy(ifr.ifr_name, device, sizeof(ifr.ifr_name));
1661 #if defined(__HAIKU__) && defined(__clang__)
1662           /*
1663            * In Haiku R1/beta4 <unistd.h> ioctl() is a macro that needs to take 4
1664            * arguments to initialize its intermediate 2-member structure fully so
1665            * that Clang does not generate a -Wmissing-field-initializers warning
1666            * (which manifests only when it runs with -Werror).  This workaround
1667            * can be removed as soon as there is a Haiku release that fixes the
1668            * problem.  See also https://review.haiku-os.org/c/haiku/+/6369
1669            */
1670           if (ioctl(fd, SIOCGIFADDR, (char *)&ifr, sizeof(ifr)) < 0) {
1671 #else
1672           if (ioctl(fd, SIOCGIFADDR, (char *)&ifr) < 0) {
1673 #endif /* __HAIKU__ && __clang__ */
1674                     if (errno == EADDRNOTAVAIL) {
1675                               (void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
1676                                   "%s: no IPv4 address assigned", device);
1677                     } else {
1678                               pcapint_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
1679                                   errno, "SIOCGIFADDR: %s", device);
1680                     }
1681                     (void)close(fd);
1682                     return (-1);
1683           }
1684           sin4 = (struct sockaddr_in *)&ifr.ifr_addr;
1685           *netp = sin4->sin_addr.s_addr;
1686           memset(&ifr, 0, sizeof(ifr));
1687 #ifdef __linux__
1688           /* XXX Work around Linux kernel bug */
1689           ifr.ifr_addr.sa_family = AF_INET;
1690 #endif
1691           (void)pcapint_strlcpy(ifr.ifr_name, device, sizeof(ifr.ifr_name));
1692 #if defined(__HAIKU__) && defined(__clang__)
1693           /* Same as above. */
1694           if (ioctl(fd, SIOCGIFNETMASK, (char *)&ifr, sizeof(ifr)) < 0) {
1695 #else
1696           if (ioctl(fd, SIOCGIFNETMASK, (char *)&ifr) < 0) {
1697 #endif /* __HAIKU__ && __clang__ */
1698                     pcapint_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
1699                         errno, "SIOCGIFNETMASK: %s", device);
1700                     (void)close(fd);
1701                     return (-1);
1702           }
1703           (void)close(fd);
1704           *maskp = sin4->sin_addr.s_addr;
1705           if (*maskp == 0) {
1706                     if (IN_CLASSA(*netp))
1707                               *maskp = IN_CLASSA_NET;
1708                     else if (IN_CLASSB(*netp))
1709                               *maskp = IN_CLASSB_NET;
1710                     else if (IN_CLASSC(*netp))
1711                               *maskp = IN_CLASSC_NET;
1712                     else {
1713                               (void)snprintf(errbuf, PCAP_ERRBUF_SIZE,
1714                                   "inet class for 0x%x unknown", *netp);
1715                               return (-1);
1716                     }
1717           }
1718           *netp &= *maskp;
1719           return (0);
1720 }
1721 #endif /* !defined(_WIN32) && !defined(MSDOS) */
1722 
1723 #ifdef ENABLE_REMOTE
1724 #include "pcap-rpcap.h"
1725 
1726 /*
1727  * Extract a substring from a string.
1728  */
1729 static char *
1730 get_substring(const char *p, size_t len, char *ebuf)
1731 {
1732           char *token;
1733 
1734           token = malloc(len + 1);
1735           if (token == NULL) {
1736                     pcapint_fmt_errmsg_for_errno(ebuf, PCAP_ERRBUF_SIZE,
1737                         errno, "malloc");
1738                     return (NULL);
1739           }
1740           memcpy(token, p, len);
1741           token[len] = '\0';
1742           return (token);
1743 }
1744 
1745 /*
1746  * Parse a capture source that might be a URL.
1747  *
1748  * If the source is not a URL, *schemep, *userinfop, *hostp, and *portp
1749  * are set to NULL, *pathp is set to point to the source, and 0 is
1750  * returned.
1751  *
1752  * If source is a URL, and the URL refers to a local device (a special
1753  * case of rpcap:), *schemep, *userinfop, *hostp, and *portp are set
1754  * to NULL, *pathp is set to point to the device name, and 0 is returned.
1755  *
1756  * If source is a URL, and it's not a special case that refers to a local
1757  * device, and the parse succeeds:
1758  *
1759  *    *schemep is set to point to an allocated string containing the scheme;
1760  *
1761  *    if user information is present in the URL, *userinfop is set to point
1762  *    to an allocated string containing the user information, otherwise
1763  *    it's set to NULL;
1764  *
1765  *    if host information is present in the URL, *hostp is set to point
1766  *    to an allocated string containing the host information, otherwise
1767  *    it's set to NULL;
1768  *
1769  *    if a port number is present in the URL, *portp is set to point
1770  *    to an allocated string containing the port number, otherwise
1771  *    it's set to NULL;
1772  *
1773  *    *pathp is set to point to an allocated string containing the
1774  *    path;
1775  *
1776  * and 0 is returned.
1777  *
1778  * If the parse fails, ebuf is set to an error string, and -1 is returned.
1779  */
1780 static int
1781 pcap_parse_source(const char *source, char **schemep, char **userinfop,
1782     char **hostp, char **portp, char **pathp, char *ebuf)
1783 {
1784           char *colonp;
1785           size_t scheme_len;
1786           char *scheme;
1787           const char *endp;
1788           size_t authority_len;
1789           char *authority;
1790           char *parsep, *atsignp, *bracketp;
1791           char *userinfo, *host, *port, *path;
1792 
1793           /*
1794            * Start out returning nothing.
1795            */
1796           *schemep = NULL;
1797           *userinfop = NULL;
1798           *hostp = NULL;
1799           *portp = NULL;
1800           *pathp = NULL;
1801 
1802           /*
1803            * RFC 3986 says:
1804            *
1805            *   URI         = scheme ":" hier-part [ "?" query ] [ "#" fragment ]
1806            *
1807            *   hier-part   = "//" authority path-abempty
1808            *               / path-absolute
1809            *               / path-rootless
1810            *               / path-empty
1811            *
1812            *   authority   = [ userinfo "@" ] host [ ":" port ]
1813            *
1814            *   userinfo    = *( unreserved / pct-encoded / sub-delims / ":" )
1815          *
1816          * Step 1: look for the ":" at the end of the scheme.
1817            * A colon in the source is *NOT* sufficient to indicate that
1818            * this is a URL, as interface names on some platforms might
1819            * include colons (e.g., I think some Solaris interfaces
1820            * might).
1821            */
1822           colonp = strchr(source, ':');
1823           if (colonp == NULL) {
1824                     /*
1825                      * The source is the device to open.
1826                      * Return a NULL pointer for the scheme, user information,
1827                      * host, and port, and return the device as the path.
1828                      */
1829                     *pathp = strdup(source);
1830                     if (*pathp == NULL) {
1831                               pcapint_fmt_errmsg_for_errno(ebuf, PCAP_ERRBUF_SIZE,
1832                                   errno, "malloc");
1833                               return (-1);
1834                     }
1835                     return (0);
1836           }
1837 
1838           /*
1839            * All schemes must have "//" after them, i.e. we only support
1840            * hier-part   = "//" authority path-abempty, not
1841            * hier-part   = path-absolute
1842            * hier-part   = path-rootless
1843            * hier-part   = path-empty
1844            *
1845            * We need that in order to distinguish between a local device
1846            * name that happens to contain a colon and a URI.
1847            */
1848           if (strncmp(colonp + 1, "//", 2) != 0) {
1849                     /*
1850                      * The source is the device to open.
1851                      * Return a NULL pointer for the scheme, user information,
1852                      * host, and port, and return the device as the path.
1853                      */
1854                     *pathp = strdup(source);
1855                     if (*pathp == NULL) {
1856                               pcapint_fmt_errmsg_for_errno(ebuf, PCAP_ERRBUF_SIZE,
1857                                   errno, "malloc");
1858                               return (-1);
1859                     }
1860                     return (0);
1861           }
1862 
1863           /*
1864            * XXX - check whether the purported scheme could be a scheme?
1865            */
1866 
1867           /*
1868            * OK, this looks like a URL.
1869            * Get the scheme.
1870            */
1871           scheme_len = colonp - source;
1872           scheme = malloc(scheme_len + 1);
1873           if (scheme == NULL) {
1874                     pcapint_fmt_errmsg_for_errno(ebuf, PCAP_ERRBUF_SIZE,
1875                         errno, "malloc");
1876                     return (-1);
1877           }
1878           memcpy(scheme, source, scheme_len);
1879           scheme[scheme_len] = '\0';
1880 
1881           /*
1882            * Treat file: specially - take everything after file:// as
1883            * the pathname.
1884            */
1885           if (pcapint_strcasecmp(scheme, "file") == 0) {
1886                     *pathp = strdup(colonp + 3);
1887                     if (*pathp == NULL) {
1888                               pcapint_fmt_errmsg_for_errno(ebuf, PCAP_ERRBUF_SIZE,
1889                                   errno, "malloc");
1890                               free(scheme);
1891                               return (-1);
1892                     }
1893                     *schemep = scheme;
1894                     return (0);
1895           }
1896 
1897           /*
1898            * The WinPcap documentation says you can specify a local
1899            * interface with "rpcap://{device}"; we special-case
1900            * that here.  If the scheme is "rpcap", and there are
1901            * no slashes past the "//", we just return the device.
1902            *
1903            * XXX - %-escaping?
1904            */
1905           if ((pcapint_strcasecmp(scheme, "rpcap") == 0 ||
1906               pcapint_strcasecmp(scheme, "rpcaps") == 0) &&
1907               strchr(colonp + 3, '/') == NULL) {
1908                     /*
1909                      * Local device.
1910                      *
1911                      * Return a NULL pointer for the scheme, user information,
1912                      * host, and port, and return the device as the path.
1913                      */
1914                     free(scheme);
1915                     *pathp = strdup(colonp + 3);
1916                     if (*pathp == NULL) {
1917                               pcapint_fmt_errmsg_for_errno(ebuf, PCAP_ERRBUF_SIZE,
1918                                   errno, "malloc");
1919                               return (-1);
1920                     }
1921                     return (0);
1922           }
1923 
1924           /*
1925            * OK, now start parsing the authority.
1926            * Get token, terminated with / or terminated at the end of
1927            * the string.
1928            */
1929           authority_len = strcspn(colonp + 3, "/");
1930           authority = get_substring(colonp + 3, authority_len, ebuf);
1931           if (authority == NULL) {
1932                     /*
1933                      * Error.
1934                      */
1935                     free(scheme);
1936                     return (-1);
1937           }
1938           endp = colonp + 3 + authority_len;
1939 
1940           /*
1941            * Now carve the authority field into its components.
1942            */
1943           parsep = authority;
1944 
1945           /*
1946            * Is there a userinfo field?
1947            */
1948           atsignp = strchr(parsep, '@');
1949           if (atsignp != NULL) {
1950                     /*
1951                      * Yes.
1952                      */
1953                     size_t userinfo_len;
1954 
1955                     userinfo_len = atsignp - parsep;
1956                     userinfo = get_substring(parsep, userinfo_len, ebuf);
1957                     if (userinfo == NULL) {
1958                               /*
1959                                * Error.
1960                                */
1961                               free(authority);
1962                               free(scheme);
1963                               return (-1);
1964                     }
1965                     parsep = atsignp + 1;
1966           } else {
1967                     /*
1968                      * No.
1969                      */
1970                     userinfo = NULL;
1971           }
1972 
1973           /*
1974            * Is there a host field?
1975            */
1976           if (*parsep == '\0') {
1977                     /*
1978                      * No; there's no host field or port field.
1979                      */
1980                     host = NULL;
1981                     port = NULL;
1982           } else {
1983                     /*
1984                      * Yes.
1985                      */
1986                     size_t host_len;
1987 
1988                     /*
1989                      * Is it an IP-literal?
1990                      */
1991                     if (*parsep == '[') {
1992                               /*
1993                                * Yes.
1994                                * Treat everything up to the closing square
1995                                * bracket as the IP-Literal; we don't worry
1996                                * about whether it's a valid IPv6address or
1997                                * IPvFuture (or an IPv4address, for that
1998                                * matter, just in case we get handed a
1999                                * URL with an IPv4 IP-Literal, of the sort
2000                                * that pcap_createsrcstr() used to generate,
2001                                * and that pcap_parsesrcstr(), in the original
2002                                * WinPcap code, accepted).
2003                                */
2004                               bracketp = strchr(parsep, ']');
2005                               if (bracketp == NULL) {
2006                                         /*
2007                                          * There's no closing square bracket.
2008                                          */
2009                                         snprintf(ebuf, PCAP_ERRBUF_SIZE,
2010                                             "IP-literal in URL doesn't end with ]");
2011                                         free(userinfo);
2012                                         free(authority);
2013                                         free(scheme);
2014                                         return (-1);
2015                               }
2016                               if (*(bracketp + 1) != '\0' &&
2017                                   *(bracketp + 1) != ':') {
2018                                         /*
2019                                          * There's extra crud after the
2020                                          * closing square bracket.
2021                                          */
2022                                         snprintf(ebuf, PCAP_ERRBUF_SIZE,
2023                                             "Extra text after IP-literal in URL");
2024                                         free(userinfo);
2025                                         free(authority);
2026                                         free(scheme);
2027                                         return (-1);
2028                               }
2029                               host_len = (bracketp - 1) - parsep;
2030                               host = get_substring(parsep + 1, host_len, ebuf);
2031                               if (host == NULL) {
2032                                         /*
2033                                          * Error.
2034                                          */
2035                                         free(userinfo);
2036                                         free(authority);
2037                                         free(scheme);
2038                                         return (-1);
2039                               }
2040                               parsep = bracketp + 1;
2041                     } else {
2042                               /*
2043                                * No.
2044                                * Treat everything up to a : or the end of
2045                                * the string as the host.
2046                                */
2047                               host_len = strcspn(parsep, ":");
2048                               host = get_substring(parsep, host_len, ebuf);
2049                               if (host == NULL) {
2050                                         /*
2051                                          * Error.
2052                                          */
2053                                         free(userinfo);
2054                                         free(authority);
2055                                         free(scheme);
2056                                         return (-1);
2057                               }
2058                               parsep = parsep + host_len;
2059                     }
2060 
2061                     /*
2062                      * Is there a port field?
2063                      */
2064                     if (*parsep == ':') {
2065                               /*
2066                                * Yes.  It's the rest of the authority field.
2067                                */
2068                               size_t port_len;
2069 
2070                               parsep++;
2071                               port_len = strlen(parsep);
2072                               port = get_substring(parsep, port_len, ebuf);
2073                               if (port == NULL) {
2074                                         /*
2075                                          * Error.
2076                                          */
2077                                         free(host);
2078                                         free(userinfo);
2079                                         free(authority);
2080                                         free(scheme);
2081                                         return (-1);
2082                               }
2083                     } else {
2084                               /*
2085                                * No.
2086                                */
2087                               port = NULL;
2088                     }
2089           }
2090           free(authority);
2091 
2092           /*
2093            * Everything else is the path.  Strip off the leading /.
2094            */
2095           if (*endp == '\0')
2096                     path = strdup("");
2097           else
2098                     path = strdup(endp + 1);
2099           if (path == NULL) {
2100                     pcapint_fmt_errmsg_for_errno(ebuf, PCAP_ERRBUF_SIZE,
2101                         errno, "malloc");
2102                     free(port);
2103                     free(host);
2104                     free(userinfo);
2105                     free(scheme);
2106                     return (-1);
2107           }
2108           *schemep = scheme;
2109           *userinfop = userinfo;
2110           *hostp = host;
2111           *portp = port;
2112           *pathp = path;
2113           return (0);
2114 }
2115 
2116 int
2117 pcapint_createsrcstr_ex(char *source, int type, const char *host, const char *port,
2118     const char *name, unsigned char uses_ssl, char *errbuf)
2119 {
2120           switch (type) {
2121 
2122           case PCAP_SRC_FILE:
2123                     pcapint_strlcpy(source, PCAP_SRC_FILE_STRING, PCAP_BUF_SIZE);
2124                     if (name != NULL && *name != '\0') {
2125                               pcapint_strlcat(source, name, PCAP_BUF_SIZE);
2126                               return (0);
2127                     } else {
2128                               snprintf(errbuf, PCAP_ERRBUF_SIZE,
2129                                   "The file name cannot be NULL.");
2130                               return (-1);
2131                     }
2132 
2133           case PCAP_SRC_IFREMOTE:
2134                     pcapint_strlcpy(source,
2135                         (uses_ssl ? "rpcaps://" : PCAP_SRC_IF_STRING),
2136                         PCAP_BUF_SIZE);
2137                     if (host != NULL && *host != '\0') {
2138                               if (strchr(host, ':') != NULL) {
2139                                         /*
2140                                          * The host name contains a colon, so it's
2141                                          * probably an IPv6 address, and needs to
2142                                          * be included in square brackets.
2143                                          */
2144                                         pcapint_strlcat(source, "[", PCAP_BUF_SIZE);
2145                                         pcapint_strlcat(source, host, PCAP_BUF_SIZE);
2146                                         pcapint_strlcat(source, "]", PCAP_BUF_SIZE);
2147                               } else
2148                                         pcapint_strlcat(source, host, PCAP_BUF_SIZE);
2149 
2150                               if (port != NULL && *port != '\0') {
2151                                         pcapint_strlcat(source, ":", PCAP_BUF_SIZE);
2152                                         pcapint_strlcat(source, port, PCAP_BUF_SIZE);
2153                               }
2154 
2155                               pcapint_strlcat(source, "/", PCAP_BUF_SIZE);
2156                     } else {
2157                               snprintf(errbuf, PCAP_ERRBUF_SIZE,
2158                                   "The host name cannot be NULL.");
2159                               return (-1);
2160                     }
2161 
2162                     if (name != NULL && *name != '\0')
2163                               pcapint_strlcat(source, name, PCAP_BUF_SIZE);
2164 
2165                     return (0);
2166 
2167           case PCAP_SRC_IFLOCAL:
2168                     pcapint_strlcpy(source, PCAP_SRC_IF_STRING, PCAP_BUF_SIZE);
2169 
2170                     if (name != NULL && *name != '\0')
2171                               pcapint_strlcat(source, name, PCAP_BUF_SIZE);
2172 
2173                     return (0);
2174 
2175           default:
2176                     snprintf(errbuf, PCAP_ERRBUF_SIZE,
2177                         "The interface type is not valid.");
2178                     return (-1);
2179           }
2180 }
2181 
2182 
2183 int
2184 pcap_createsrcstr(char *source, int type, const char *host, const char *port,
2185     const char *name, char *errbuf)
2186 {
2187           return (pcapint_createsrcstr_ex(source, type, host, port, name, 0, errbuf));
2188 }
2189 
2190 int
2191 pcapint_parsesrcstr_ex(const char *source, int *type, char *host, char *port,
2192     char *name, unsigned char *uses_ssl, char *errbuf)
2193 {
2194           char *scheme, *tmpuserinfo, *tmphost, *tmpport, *tmppath;
2195 
2196           /* Initialization stuff */
2197           if (host)
2198                     *host = '\0';
2199           if (port)
2200                     *port = '\0';
2201           if (name)
2202                     *name = '\0';
2203           if (uses_ssl)
2204                     *uses_ssl = 0;
2205 
2206           /* Parse the source string */
2207           if (pcap_parse_source(source, &scheme, &tmpuserinfo, &tmphost,
2208               &tmpport, &tmppath, errbuf) == -1) {
2209                     /*
2210                      * Fail.
2211                      */
2212                     return (-1);
2213           }
2214 
2215           if (scheme == NULL) {
2216                     /*
2217                      * Local device.
2218                      */
2219                     if (name && tmppath)
2220                               pcapint_strlcpy(name, tmppath, PCAP_BUF_SIZE);
2221                     if (type)
2222                               *type = PCAP_SRC_IFLOCAL;
2223                     free(tmppath);
2224                     free(tmpport);
2225                     free(tmphost);
2226                     free(tmpuserinfo);
2227                     return (0);
2228           }
2229 
2230           int is_rpcap = 0;
2231           if (strcmp(scheme, "rpcaps") == 0) {
2232                     is_rpcap = 1;
2233                     if (uses_ssl) *uses_ssl = 1;
2234           } else if (strcmp(scheme, "rpcap") == 0) {
2235                     is_rpcap = 1;
2236           }
2237 
2238           if (is_rpcap) {
2239                     /*
2240                      * rpcap[s]://
2241                      *
2242                      * pcap_parse_source() has already handled the case of
2243                      * rpcap[s]://device
2244                      */
2245                     if (host && tmphost) {
2246                               if (tmpuserinfo)
2247                                         snprintf(host, PCAP_BUF_SIZE, "%s@%s",
2248                                             tmpuserinfo, tmphost);
2249                               else
2250                                         pcapint_strlcpy(host, tmphost, PCAP_BUF_SIZE);
2251                     }
2252                     if (port && tmpport)
2253                               pcapint_strlcpy(port, tmpport, PCAP_BUF_SIZE);
2254                     if (name && tmppath)
2255                               pcapint_strlcpy(name, tmppath, PCAP_BUF_SIZE);
2256                     if (type)
2257                               *type = PCAP_SRC_IFREMOTE;
2258                     free(tmppath);
2259                     free(tmpport);
2260                     free(tmphost);
2261                     free(tmpuserinfo);
2262                     free(scheme);
2263                     return (0);
2264           }
2265 
2266           if (strcmp(scheme, "file") == 0) {
2267                     /*
2268                      * file://
2269                      */
2270                     if (name && tmppath)
2271                               pcapint_strlcpy(name, tmppath, PCAP_BUF_SIZE);
2272                     if (type)
2273                               *type = PCAP_SRC_FILE;
2274                     free(tmppath);
2275                     free(tmpport);
2276                     free(tmphost);
2277                     free(tmpuserinfo);
2278                     free(scheme);
2279                     return (0);
2280           }
2281 
2282           /*
2283            * Neither rpcap: nor file:; just treat the entire string
2284            * as a local device.
2285            */
2286           if (name)
2287                     pcapint_strlcpy(name, source, PCAP_BUF_SIZE);
2288           if (type)
2289                     *type = PCAP_SRC_IFLOCAL;
2290           free(tmppath);
2291           free(tmpport);
2292           free(tmphost);
2293           free(tmpuserinfo);
2294           free(scheme);
2295           return (0);
2296 }
2297 
2298 int
2299 pcap_parsesrcstr(const char *source, int *type, char *host, char *port,
2300     char *name, char *errbuf)
2301 {
2302           return (pcapint_parsesrcstr_ex(source, type, host, port, name, NULL, errbuf));
2303 }
2304 #endif
2305 
2306 pcap_t *
2307 pcap_create(const char *device, char *errbuf)
2308 {
2309           size_t i;
2310           int is_theirs;
2311           pcap_t *p;
2312           char *device_str;
2313 
2314           /*
2315            * A null device name is equivalent to the "any" device -
2316            * which might not be supported on this platform, but
2317            * this means that you'll get a "not supported" error
2318            * rather than, say, a crash when we try to dereference
2319            * the null pointer.
2320            */
2321           if (device == NULL)
2322                     device_str = strdup("any");
2323           else {
2324 #ifdef _WIN32
2325                     /*
2326                      * On Windows, for backwards compatibility reasons,
2327                      * pcap_lookupdev() returns a pointer to a sequence of
2328                      * pairs of UTF-16LE device names and local code page
2329                      * description strings.
2330                      *
2331                      * This means that if a program uses pcap_lookupdev()
2332                      * to get a default device, and hands that to an API
2333                      * that opens devices, we'll get handed a UTF-16LE
2334                      * string, not a string in the local code page.
2335                      *
2336                      * To work around that, we check whether the string
2337                      * looks as if it might be a UTF-16LE string and, if
2338                      * so, convert it back to the local code page's
2339                      * extended ASCII.
2340                      *
2341                      * We disable that check in "new API" mode, because:
2342                      *
2343                      *   1) You *cannot* reliably detect whether a
2344                      *   string is UTF-16LE or not; "a" could either
2345                      *   be a one-character ASCII string or the first
2346                      *   character of a UTF-16LE string.
2347                      *
2348                      *   2) Doing that test can run past the end of
2349                      *   the string, if it's a 1-character ASCII
2350                      *   string
2351                      *
2352                      * This particular version of this heuristic dates
2353                      * back to WinPcap 4.1.1; PacketOpenAdapter() does
2354                      * uses the same heuristic, with the exact same
2355                      * vulnerability.
2356                      *
2357                      * That's why we disable this in "new API" mode.
2358                      * We keep it around in legacy mode for backwards
2359                      * compatibility.
2360                      */
2361                     if (!pcapint_new_api && device[0] != '\0' && device[1] == '\0') {
2362                               size_t length;
2363 
2364                               length = wcslen((wchar_t *)device);
2365                               device_str = (char *)malloc(length + 1);
2366                               if (device_str == NULL) {
2367                                         pcapint_fmt_errmsg_for_errno(errbuf,
2368                                             PCAP_ERRBUF_SIZE, errno,
2369                                             "malloc");
2370                                         return (NULL);
2371                               }
2372 
2373                               snprintf(device_str, length + 1, "%ws",
2374                                   (const wchar_t *)device);
2375                     } else
2376 #endif
2377                               device_str = strdup(device);
2378           }
2379           if (device_str == NULL) {
2380                     pcapint_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
2381                         errno, "malloc");
2382                     return (NULL);
2383           }
2384 
2385           /*
2386            * Try each of the non-local-network-interface capture
2387            * source types until we find one that works for this
2388            * device or run out of types.
2389            */
2390           for (i = 0; capture_source_types[i].create_op != NULL; i++) {
2391                     is_theirs = 0;
2392                     p = capture_source_types[i].create_op(device_str, errbuf,
2393                         &is_theirs);
2394                     if (is_theirs) {
2395                               /*
2396                                * The device name refers to a device of the
2397                                * type in question; either it succeeded,
2398                                * in which case p refers to a pcap_t to
2399                                * later activate for the device, or it
2400                                * failed, in which case p is null and we
2401                                * should return that to report the failure
2402                                * to create.
2403                                */
2404                               if (p == NULL) {
2405                                         /*
2406                                          * We assume the caller filled in errbuf.
2407                                          */
2408                                         free(device_str);
2409                                         return (NULL);
2410                               }
2411                               p->opt.device = device_str;
2412                               return (p);
2413                     }
2414           }
2415 
2416           /*
2417            * OK, try it as a regular network interface.
2418            */
2419           p = pcapint_create_interface(device_str, errbuf);
2420           if (p == NULL) {
2421                     /*
2422                      * We assume the caller filled in errbuf.
2423                      */
2424                     free(device_str);
2425                     return (NULL);
2426           }
2427           p->opt.device = device_str;
2428           return (p);
2429 }
2430 
2431 /*
2432  * Set nonblocking mode on an unactivated pcap_t; this sets a flag
2433  * checked by pcap_activate(), which sets the mode after calling
2434  * the activate routine.
2435  */
2436 static int
2437 pcap_setnonblock_unactivated(pcap_t *p, int nonblock)
2438 {
2439           p->opt.nonblock = nonblock;
2440           return (0);
2441 }
2442 
2443 static void
2444 initialize_ops(pcap_t *p)
2445 {
2446           /*
2447            * Set operation pointers for operations that only work on
2448            * an activated pcap_t to point to a routine that returns
2449            * a "this isn't activated" error.
2450            */
2451           p->read_op = pcap_read_not_initialized;
2452           p->inject_op = pcap_inject_not_initialized;
2453           p->setfilter_op = pcap_setfilter_not_initialized;
2454           p->setdirection_op = pcap_setdirection_not_initialized;
2455           p->set_datalink_op = pcap_set_datalink_not_initialized;
2456           p->getnonblock_op = pcap_getnonblock_not_initialized;
2457           p->stats_op = pcap_stats_not_initialized;
2458 #ifdef _WIN32
2459           p->stats_ex_op = pcap_stats_ex_not_initialized;
2460           p->setbuff_op = pcap_setbuff_not_initialized;
2461           p->setmode_op = pcap_setmode_not_initialized;
2462           p->setmintocopy_op = pcap_setmintocopy_not_initialized;
2463           p->getevent_op = pcap_getevent_not_initialized;
2464           p->oid_get_request_op = pcap_oid_get_request_not_initialized;
2465           p->oid_set_request_op = pcap_oid_set_request_not_initialized;
2466           p->sendqueue_transmit_op = pcap_sendqueue_transmit_not_initialized;
2467           p->setuserbuffer_op = pcap_setuserbuffer_not_initialized;
2468           p->live_dump_op = pcap_live_dump_not_initialized;
2469           p->live_dump_ended_op = pcap_live_dump_ended_not_initialized;
2470           p->get_airpcap_handle_op = pcap_get_airpcap_handle_not_initialized;
2471 #endif
2472 
2473           /*
2474            * Default cleanup operation - implementations can override
2475            * this, but should call pcapint_cleanup_live_common() after
2476            * doing their own additional cleanup.
2477            */
2478           p->cleanup_op = pcapint_cleanup_live_common;
2479 
2480           /*
2481            * In most cases, the standard one-shot callback can
2482            * be used for pcap_next()/pcap_next_ex().
2483            */
2484           p->oneshot_callback = pcapint_oneshot;
2485 
2486           /*
2487            * Default breakloop operation - implementations can override
2488            * this, but should call pcapint_breakloop_common() before doing
2489            * their own logic.
2490            */
2491           p->breakloop_op = pcapint_breakloop_common;
2492 }
2493 
2494 static pcap_t *
2495 pcap_alloc_pcap_t(char *ebuf, size_t total_size, size_t private_offset)
2496 {
2497           char *chunk;
2498           pcap_t *p;
2499 
2500           /*
2501            * total_size is the size of a structure containing a pcap_t
2502            * followed by a private structure.
2503            */
2504           chunk = calloc(total_size, 1);
2505           if (chunk == NULL) {
2506                     pcapint_fmt_errmsg_for_errno(ebuf, PCAP_ERRBUF_SIZE,
2507                         errno, "malloc");
2508                     return (NULL);
2509           }
2510 
2511           /*
2512            * Get a pointer to the pcap_t at the beginning.
2513            */
2514           p = (pcap_t *)chunk;
2515 
2516 #ifdef _WIN32
2517           p->handle = INVALID_HANDLE_VALUE;       /* not opened yet */
2518 #else /* _WIN32 */
2519           p->fd = -1;         /* not opened yet */
2520 #ifndef MSDOS
2521           p->selectable_fd = -1;
2522           p->required_select_timeout = NULL;
2523 #endif /* MSDOS */
2524 #endif /* _WIN32 */
2525 
2526           /*
2527            * private_offset is the offset, in bytes, of the private
2528            * data from the beginning of the structure.
2529            *
2530            * Set the pointer to the private data; that's private_offset
2531            * bytes past the pcap_t.
2532            */
2533           p->priv = (void *)(chunk + private_offset);
2534 
2535           return (p);
2536 }
2537 
2538 pcap_t *
2539 pcapint_create_common(char *ebuf, size_t total_size, size_t private_offset)
2540 {
2541           pcap_t *p;
2542 
2543           p = pcap_alloc_pcap_t(ebuf, total_size, private_offset);
2544           if (p == NULL)
2545                     return (NULL);
2546 
2547           /*
2548            * Default to "can't set rfmon mode"; if it's supported by
2549            * a platform, the create routine that called us can set
2550            * the op to its routine to check whether a particular
2551            * device supports it.
2552            */
2553           p->can_set_rfmon_op = pcap_cant_set_rfmon;
2554 
2555           /*
2556            * If pcap_setnonblock() is called on a not-yet-activated
2557            * pcap_t, default to setting a flag and turning
2558            * on non-blocking mode when activated.
2559            */
2560           p->setnonblock_op = pcap_setnonblock_unactivated;
2561 
2562           initialize_ops(p);
2563 
2564           /* put in some defaults*/
2565           p->snapshot = 0;              /* max packet size unspecified */
2566           p->opt.timeout = 0;           /* no timeout specified */
2567           p->opt.buffer_size = 0;                 /* use the platform's default */
2568           p->opt.promisc = 0;
2569           p->opt.rfmon = 0;
2570           p->opt.immediate = 0;
2571           p->opt.tstamp_type = -1;      /* default to not setting time stamp type */
2572           p->opt.tstamp_precision = PCAP_TSTAMP_PRECISION_MICRO;
2573           /*
2574            * Platform-dependent options.
2575            */
2576 #ifdef __linux__
2577           p->opt.protocol = 0;
2578 #endif
2579 #ifdef _WIN32
2580           p->opt.nocapture_local = 0;
2581 #endif
2582 
2583           /*
2584            * Start out with no BPF code generation flags set.
2585            */
2586           p->bpf_codegen_flags = 0;
2587 
2588           return (p);
2589 }
2590 
2591 int
2592 pcapint_check_activated(pcap_t *p)
2593 {
2594           if (p->activated) {
2595                     snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "can't perform "
2596                               " operation on activated capture");
2597                     return (-1);
2598           }
2599           return (0);
2600 }
2601 
2602 int
2603 pcap_set_snaplen(pcap_t *p, int snaplen)
2604 {
2605           if (pcapint_check_activated(p))
2606                     return (PCAP_ERROR_ACTIVATED);
2607           p->snapshot = snaplen;
2608           return (0);
2609 }
2610 
2611 int
2612 pcap_set_promisc(pcap_t *p, int promisc)
2613 {
2614           if (pcapint_check_activated(p))
2615                     return (PCAP_ERROR_ACTIVATED);
2616           p->opt.promisc = promisc;
2617           return (0);
2618 }
2619 
2620 int
2621 pcap_set_rfmon(pcap_t *p, int rfmon)
2622 {
2623           if (pcapint_check_activated(p))
2624                     return (PCAP_ERROR_ACTIVATED);
2625           p->opt.rfmon = rfmon;
2626           return (0);
2627 }
2628 
2629 int
2630 pcap_set_timeout(pcap_t *p, int timeout_ms)
2631 {
2632           if (pcapint_check_activated(p))
2633                     return (PCAP_ERROR_ACTIVATED);
2634           p->opt.timeout = timeout_ms;
2635           return (0);
2636 }
2637 
2638 int
2639 pcap_set_tstamp_type(pcap_t *p, int tstamp_type)
2640 {
2641           int i;
2642 
2643           if (pcapint_check_activated(p))
2644                     return (PCAP_ERROR_ACTIVATED);
2645 
2646           /*
2647            * The argument should have been u_int, but that's too late
2648            * to change now - it's an API.
2649            */
2650           if (tstamp_type < 0)
2651                     return (PCAP_WARNING_TSTAMP_TYPE_NOTSUP);
2652 
2653           /*
2654            * If p->tstamp_type_count is 0, we only support PCAP_TSTAMP_HOST;
2655            * the default time stamp type is PCAP_TSTAMP_HOST.
2656            */
2657           if (p->tstamp_type_count == 0) {
2658                     if (tstamp_type == PCAP_TSTAMP_HOST) {
2659                               p->opt.tstamp_type = tstamp_type;
2660                               return (0);
2661                     }
2662           } else {
2663                     /*
2664                      * Check whether we claim to support this type of time stamp.
2665                      */
2666                     for (i = 0; i < p->tstamp_type_count; i++) {
2667                               if (p->tstamp_type_list[i] == (u_int)tstamp_type) {
2668                                         /*
2669                                          * Yes.
2670                                          */
2671                                         p->opt.tstamp_type = tstamp_type;
2672                                         return (0);
2673                               }
2674                     }
2675           }
2676 
2677           /*
2678            * We don't support this type of time stamp.
2679            */
2680           return (PCAP_WARNING_TSTAMP_TYPE_NOTSUP);
2681 }
2682 
2683 int
2684 pcap_set_immediate_mode(pcap_t *p, int immediate)
2685 {
2686           if (pcapint_check_activated(p))
2687                     return (PCAP_ERROR_ACTIVATED);
2688           p->opt.immediate = immediate;
2689           return (0);
2690 }
2691 
2692 int
2693 pcap_set_buffer_size(pcap_t *p, int buffer_size)
2694 {
2695           if (pcapint_check_activated(p))
2696                     return (PCAP_ERROR_ACTIVATED);
2697           if (buffer_size <= 0) {
2698                     /*
2699                      * Silently ignore invalid values.
2700                      */
2701                     return (0);
2702           }
2703           p->opt.buffer_size = buffer_size;
2704           return (0);
2705 }
2706 
2707 int
2708 pcap_set_tstamp_precision(pcap_t *p, int tstamp_precision)
2709 {
2710           int i;
2711 
2712           if (pcapint_check_activated(p))
2713                     return (PCAP_ERROR_ACTIVATED);
2714 
2715           /*
2716            * The argument should have been u_int, but that's too late
2717            * to change now - it's an API.
2718            */
2719           if (tstamp_precision < 0)
2720                     return (PCAP_ERROR_TSTAMP_PRECISION_NOTSUP);
2721 
2722           /*
2723            * If p->tstamp_precision_count is 0, we only support setting
2724            * the time stamp precision to microsecond precision; every
2725            * pcap module *MUST* support microsecond precision, even if
2726            * it does so by converting the native precision to
2727            * microseconds.
2728            */
2729           if (p->tstamp_precision_count == 0) {
2730                     if (tstamp_precision == PCAP_TSTAMP_PRECISION_MICRO) {
2731                               p->opt.tstamp_precision = tstamp_precision;
2732                               return (0);
2733                     }
2734           } else {
2735                     /*
2736                      * Check whether we claim to support this precision of
2737                      * time stamp.
2738                      */
2739                     for (i = 0; i < p->tstamp_precision_count; i++) {
2740                               if (p->tstamp_precision_list[i] == (u_int)tstamp_precision) {
2741                                         /*
2742                                          * Yes.
2743                                          */
2744                                         p->opt.tstamp_precision = tstamp_precision;
2745                                         return (0);
2746                               }
2747                     }
2748           }
2749 
2750           /*
2751            * We don't support this time stamp precision.
2752            */
2753           return (PCAP_ERROR_TSTAMP_PRECISION_NOTSUP);
2754 }
2755 
2756 int
2757 pcap_get_tstamp_precision(pcap_t *p)
2758 {
2759         return (p->opt.tstamp_precision);
2760 }
2761 
2762 int
2763 pcap_activate(pcap_t *p)
2764 {
2765           int status;
2766 
2767           /*
2768            * Catch attempts to re-activate an already-activated
2769            * pcap_t; this should, for example, catch code that
2770            * calls pcap_open_live() followed by pcap_activate(),
2771            * as some code that showed up in a Stack Exchange
2772            * question did.
2773            */
2774           if (pcapint_check_activated(p))
2775                     return (PCAP_ERROR_ACTIVATED);
2776           status = p->activate_op(p);
2777           if (status >= 0) {
2778                     /*
2779                      * If somebody requested non-blocking mode before
2780                      * calling pcap_activate(), turn it on now.
2781                      */
2782                     if (p->opt.nonblock) {
2783                               status = p->setnonblock_op(p, 1);
2784                               if (status < 0) {
2785                                         /*
2786                                          * Failed.  Undo everything done by
2787                                          * the activate operation.
2788                                          */
2789                                         p->cleanup_op(p);
2790                                         initialize_ops(p);
2791                                         return (status);
2792                               }
2793                     }
2794                     p->activated = 1;
2795           } else {
2796                     if (p->errbuf[0] == '\0') {
2797                               /*
2798                                * No error message supplied by the activate routine;
2799                                * for the benefit of programs that don't specially
2800                                * handle errors other than PCAP_ERROR, return the
2801                                * error message corresponding to the status.
2802                                */
2803                               snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "%s",
2804                                   pcap_statustostr(status));
2805                     }
2806 
2807                     /*
2808                      * Undo any operation pointer setting, etc. done by
2809                      * the activate operation.
2810                      */
2811                     initialize_ops(p);
2812           }
2813           return (status);
2814 }
2815 
2816 pcap_t *
2817 pcap_open_live(const char *device, int snaplen, int promisc, int to_ms, char *errbuf)
2818 {
2819           pcap_t *p;
2820           int status;
2821 #ifdef ENABLE_REMOTE
2822           char host[PCAP_BUF_SIZE + 1];
2823           char port[PCAP_BUF_SIZE + 1];
2824           char name[PCAP_BUF_SIZE + 1];
2825           int srctype;
2826 
2827           /*
2828            * A null device name is equivalent to the "any" device -
2829            * which might not be supported on this platform, but
2830            * this means that you'll get a "not supported" error
2831            * rather than, say, a crash when we try to dereference
2832            * the null pointer.
2833            */
2834           if (device == NULL)
2835                     device = "any";
2836 
2837           /*
2838            * Retrofit - we have to make older applications compatible with
2839            * remote capture.
2840            * So we're calling pcap_open_remote() from here; this is a very
2841            * dirty hack.
2842            * Obviously, we cannot exploit all the new features; for instance,
2843            * we cannot send authentication, we cannot use a UDP data connection,
2844            * and so on.
2845            */
2846           if (pcap_parsesrcstr(device, &srctype, host, port, name, errbuf))
2847                     return (NULL);
2848 
2849           if (srctype == PCAP_SRC_IFREMOTE) {
2850                     /*
2851                      * Although we already have host, port and iface, we prefer
2852                      * to pass only 'device' to pcap_open_rpcap(), so that it has
2853                      * to call pcap_parsesrcstr() again.
2854                      * This is less optimized, but much clearer.
2855                      */
2856                     return (pcap_open_rpcap(device, snaplen,
2857                         promisc ? PCAP_OPENFLAG_PROMISCUOUS : 0, to_ms,
2858                         NULL, errbuf));
2859           }
2860           if (srctype == PCAP_SRC_FILE) {
2861                     snprintf(errbuf, PCAP_ERRBUF_SIZE, "unknown URL scheme \"file\"");
2862                     return (NULL);
2863           }
2864           if (srctype == PCAP_SRC_IFLOCAL) {
2865                     /*
2866                      * If it starts with rpcap://, that refers to a local device
2867                      * (no host part in the URL). Remove the rpcap://, and
2868                      * fall through to the regular open path.
2869                      */
2870                     if (strncmp(device, PCAP_SRC_IF_STRING, strlen(PCAP_SRC_IF_STRING)) == 0) {
2871                               size_t len = strlen(device) - strlen(PCAP_SRC_IF_STRING) + 1;
2872 
2873                               if (len > 0)
2874                                         device += strlen(PCAP_SRC_IF_STRING);
2875                     }
2876           }
2877 #endif    /* ENABLE_REMOTE */
2878 
2879           p = pcap_create(device, errbuf);
2880           if (p == NULL)
2881                     return (NULL);
2882           status = pcap_set_snaplen(p, snaplen);
2883           if (status < 0)
2884                     goto fail;
2885           status = pcap_set_promisc(p, promisc);
2886           if (status < 0)
2887                     goto fail;
2888           status = pcap_set_timeout(p, to_ms);
2889           if (status < 0)
2890                     goto fail;
2891           /*
2892            * Mark this as opened with pcap_open_live(), so that, for
2893            * example, we show the full list of DLT_ values, rather
2894            * than just the ones that are compatible with capturing
2895            * when not in monitor mode.  That allows existing applications
2896            * to work the way they used to work, but allows new applications
2897            * that know about the new open API to, for example, find out the
2898            * DLT_ values that they can select without changing whether
2899            * the adapter is in monitor mode or not.
2900            */
2901           p->oldstyle = 1;
2902           status = pcap_activate(p);
2903           if (status < 0)
2904                     goto fail;
2905           return (p);
2906 fail:
2907           if (status == PCAP_ERROR) {
2908                     /*
2909                      * Another buffer is a bit cumbersome, but it avoids
2910                      * -Wformat-truncation.
2911                      */
2912                     char trimbuf[PCAP_ERRBUF_SIZE - 5]; /* 2 bytes shorter */
2913 
2914                     pcapint_strlcpy(trimbuf, p->errbuf, sizeof(trimbuf));
2915                     snprintf(errbuf, PCAP_ERRBUF_SIZE, "%s: %.*s", device,
2916                         PCAP_ERRBUF_SIZE - 3, trimbuf);
2917           } else if (status == PCAP_ERROR_NO_SUCH_DEVICE ||
2918               status == PCAP_ERROR_PERM_DENIED ||
2919               status == PCAP_ERROR_PROMISC_PERM_DENIED) {
2920                     /*
2921                      * Only show the additional message if it's not
2922                      * empty.
2923                      */
2924                     if (p->errbuf[0] != '\0') {
2925                               /*
2926                                * Idem.
2927                                */
2928                               char trimbuf[PCAP_ERRBUF_SIZE - 8]; /* 2 bytes shorter */
2929 
2930                               pcapint_strlcpy(trimbuf, p->errbuf, sizeof(trimbuf));
2931                               snprintf(errbuf, PCAP_ERRBUF_SIZE, "%s: %s (%.*s)",
2932                                   device, pcap_statustostr(status),
2933                                   PCAP_ERRBUF_SIZE - 6, trimbuf);
2934                     } else {
2935                               snprintf(errbuf, PCAP_ERRBUF_SIZE, "%s: %s",
2936                                   device, pcap_statustostr(status));
2937                     }
2938           } else {
2939                     snprintf(errbuf, PCAP_ERRBUF_SIZE, "%s: %s", device,
2940                         pcap_statustostr(status));
2941           }
2942           pcap_close(p);
2943           return (NULL);
2944 }
2945 
2946 pcap_t *
2947 pcapint_open_offline_common(char *ebuf, size_t total_size, size_t private_offset)
2948 {
2949           pcap_t *p;
2950 
2951           p = pcap_alloc_pcap_t(ebuf, total_size, private_offset);
2952           if (p == NULL)
2953                     return (NULL);
2954 
2955           p->opt.tstamp_precision = PCAP_TSTAMP_PRECISION_MICRO;
2956 
2957           return (p);
2958 }
2959 
2960 int
2961 pcap_dispatch(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
2962 {
2963           return (p->read_op(p, cnt, callback, user));
2964 }
2965 
2966 int
2967 pcap_loop(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
2968 {
2969           register int n;
2970 
2971           for (;;) {
2972                     if (p->rfile != NULL) {
2973                               /*
2974                                * 0 means EOF, so don't loop if we get 0.
2975                                */
2976                               n = pcapint_offline_read(p, cnt, callback, user);
2977                     } else {
2978                               /*
2979                                * XXX keep reading until we get something
2980                                * (or an error occurs)
2981                                */
2982                               do {
2983                                         n = p->read_op(p, cnt, callback, user);
2984                               } while (n == 0);
2985                     }
2986                     if (n <= 0)
2987                               return (n);
2988                     if (!PACKET_COUNT_IS_UNLIMITED(cnt)) {
2989                               cnt -= n;
2990                               if (cnt <= 0)
2991                                         return (0);
2992                     }
2993           }
2994 }
2995 
2996 /*
2997  * Force the loop in "pcap_read()" or "pcap_read_offline()" to terminate.
2998  */
2999 void
3000 pcap_breakloop(pcap_t *p)
3001 {
3002           p->breakloop_op(p);
3003 }
3004 
3005 int
3006 pcap_datalink(pcap_t *p)
3007 {
3008           if (!p->activated)
3009                     return (PCAP_ERROR_NOT_ACTIVATED);
3010           return (p->linktype);
3011 }
3012 
3013 int
3014 pcap_datalink_ext(pcap_t *p)
3015 {
3016           if (!p->activated)
3017                     return (PCAP_ERROR_NOT_ACTIVATED);
3018           return (p->linktype_ext);
3019 }
3020 
3021 int
3022 pcap_list_datalinks(pcap_t *p, int **dlt_buffer)
3023 {
3024           if (!p->activated)
3025                     return (PCAP_ERROR_NOT_ACTIVATED);
3026           if (p->dlt_count == 0) {
3027                     /*
3028                      * We couldn't fetch the list of DLTs, which means
3029                      * this platform doesn't support changing the
3030                      * DLT for an interface.  Return a list of DLTs
3031                      * containing only the DLT this device supports.
3032                      */
3033                     *dlt_buffer = (int*)malloc(sizeof(**dlt_buffer));
3034                     if (*dlt_buffer == NULL) {
3035                               pcapint_fmt_errmsg_for_errno(p->errbuf, sizeof(p->errbuf),
3036                                   errno, "malloc");
3037                               return (PCAP_ERROR);
3038                     }
3039                     **dlt_buffer = p->linktype;
3040                     return (1);
3041           } else {
3042                     *dlt_buffer = (int*)calloc(p->dlt_count, sizeof(**dlt_buffer));
3043                     if (*dlt_buffer == NULL) {
3044                               pcapint_fmt_errmsg_for_errno(p->errbuf, sizeof(p->errbuf),
3045                                   errno, "malloc");
3046                               return (PCAP_ERROR);
3047                     }
3048                     (void)memcpy(*dlt_buffer, p->dlt_list,
3049                         sizeof(**dlt_buffer) * p->dlt_count);
3050                     return (p->dlt_count);
3051           }
3052 }
3053 
3054 /*
3055  * In Windows, you might have a library built with one version of the
3056  * C runtime library and an application built with another version of
3057  * the C runtime library, which means that the library might use one
3058  * version of malloc() and free() and the application might use another
3059  * version of malloc() and free().  If so, that means something
3060  * allocated by the library cannot be freed by the application, so we
3061  * need to have a pcap_free_datalinks() routine to free up the list
3062  * allocated by pcap_list_datalinks(), even though it's just a wrapper
3063  * around free().
3064  */
3065 void
3066 pcap_free_datalinks(int *dlt_list)
3067 {
3068           free(dlt_list);
3069 }
3070 
3071 int
3072 pcap_set_datalink(pcap_t *p, int dlt)
3073 {
3074           int i;
3075           const char *dlt_name;
3076 
3077           if (dlt < 0)
3078                     goto unsupported;
3079 
3080           if (p->dlt_count == 0 || p->set_datalink_op == NULL) {
3081                     /*
3082                      * We couldn't fetch the list of DLTs, or we don't
3083                      * have a "set datalink" operation, which means
3084                      * this platform doesn't support changing the
3085                      * DLT for an interface.  Check whether the new
3086                      * DLT is the one this interface supports.
3087                      */
3088                     if (p->linktype != dlt)
3089                               goto unsupported;
3090 
3091                     /*
3092                      * It is, so there's nothing we need to do here.
3093                      */
3094                     return (0);
3095           }
3096           for (i = 0; i < p->dlt_count; i++)
3097                     if (p->dlt_list[i] == (u_int)dlt)
3098                               break;
3099           if (i >= p->dlt_count)
3100                     goto unsupported;
3101           if (p->dlt_count == 2 && p->dlt_list[0] == DLT_EN10MB &&
3102               dlt == DLT_DOCSIS) {
3103                     /*
3104                      * This is presumably an Ethernet device, as the first
3105                      * link-layer type it offers is DLT_EN10MB, and the only
3106                      * other type it offers is DLT_DOCSIS.  That means that
3107                      * we can't tell the driver to supply DOCSIS link-layer
3108                      * headers - we're just pretending that's what we're
3109                      * getting, as, presumably, we're capturing on a dedicated
3110                      * link to a Cisco Cable Modem Termination System, and
3111                      * it's putting raw DOCSIS frames on the wire inside low-level
3112                      * Ethernet framing.
3113                      */
3114                     p->linktype = dlt;
3115                     return (0);
3116           }
3117           if (p->set_datalink_op(p, dlt) == -1)
3118                     return (-1);
3119           p->linktype = dlt;
3120           return (0);
3121 
3122 unsupported:
3123           dlt_name = pcap_datalink_val_to_name(dlt);
3124           if (dlt_name != NULL) {
3125                     (void) snprintf(p->errbuf, sizeof(p->errbuf),
3126                         "%s is not one of the DLTs supported by this device",
3127                         dlt_name);
3128           } else {
3129                     (void) snprintf(p->errbuf, sizeof(p->errbuf),
3130                         "DLT %d is not one of the DLTs supported by this device",
3131                         dlt);
3132           }
3133           return (-1);
3134 }
3135 
3136 /*
3137  * This array is designed for mapping upper and lower case letter
3138  * together for a case independent comparison.  The mappings are
3139  * based upon ascii character sequences.
3140  */
3141 static const u_char charmap[] = {
3142           (u_char)'\000', (u_char)'\001', (u_char)'\002', (u_char)'\003',
3143           (u_char)'\004', (u_char)'\005', (u_char)'\006', (u_char)'\007',
3144           (u_char)'\010', (u_char)'\011', (u_char)'\012', (u_char)'\013',
3145           (u_char)'\014', (u_char)'\015', (u_char)'\016', (u_char)'\017',
3146           (u_char)'\020', (u_char)'\021', (u_char)'\022', (u_char)'\023',
3147           (u_char)'\024', (u_char)'\025', (u_char)'\026', (u_char)'\027',
3148           (u_char)'\030', (u_char)'\031', (u_char)'\032', (u_char)'\033',
3149           (u_char)'\034', (u_char)'\035', (u_char)'\036', (u_char)'\037',
3150           (u_char)'\040', (u_char)'\041', (u_char)'\042', (u_char)'\043',
3151           (u_char)'\044', (u_char)'\045', (u_char)'\046', (u_char)'\047',
3152           (u_char)'\050', (u_char)'\051', (u_char)'\052', (u_char)'\053',
3153           (u_char)'\054', (u_char)'\055', (u_char)'\056', (u_char)'\057',
3154           (u_char)'\060', (u_char)'\061', (u_char)'\062', (u_char)'\063',
3155           (u_char)'\064', (u_char)'\065', (u_char)'\066', (u_char)'\067',
3156           (u_char)'\070', (u_char)'\071', (u_char)'\072', (u_char)'\073',
3157           (u_char)'\074', (u_char)'\075', (u_char)'\076', (u_char)'\077',
3158           (u_char)'\100', (u_char)'\141', (u_char)'\142', (u_char)'\143',
3159           (u_char)'\144', (u_char)'\145', (u_char)'\146', (u_char)'\147',
3160           (u_char)'\150', (u_char)'\151', (u_char)'\152', (u_char)'\153',
3161           (u_char)'\154', (u_char)'\155', (u_char)'\156', (u_char)'\157',
3162           (u_char)'\160', (u_char)'\161', (u_char)'\162', (u_char)'\163',
3163           (u_char)'\164', (u_char)'\165', (u_char)'\166', (u_char)'\167',
3164           (u_char)'\170', (u_char)'\171', (u_char)'\172', (u_char)'\133',
3165           (u_char)'\134', (u_char)'\135', (u_char)'\136', (u_char)'\137',
3166           (u_char)'\140', (u_char)'\141', (u_char)'\142', (u_char)'\143',
3167           (u_char)'\144', (u_char)'\145', (u_char)'\146', (u_char)'\147',
3168           (u_char)'\150', (u_char)'\151', (u_char)'\152', (u_char)'\153',
3169           (u_char)'\154', (u_char)'\155', (u_char)'\156', (u_char)'\157',
3170           (u_char)'\160', (u_char)'\161', (u_char)'\162', (u_char)'\163',
3171           (u_char)'\164', (u_char)'\165', (u_char)'\166', (u_char)'\167',
3172           (u_char)'\170', (u_char)'\171', (u_char)'\172', (u_char)'\173',
3173           (u_char)'\174', (u_char)'\175', (u_char)'\176', (u_char)'\177',
3174           (u_char)'\200', (u_char)'\201', (u_char)'\202', (u_char)'\203',
3175           (u_char)'\204', (u_char)'\205', (u_char)'\206', (u_char)'\207',
3176           (u_char)'\210', (u_char)'\211', (u_char)'\212', (u_char)'\213',
3177           (u_char)'\214', (u_char)'\215', (u_char)'\216', (u_char)'\217',
3178           (u_char)'\220', (u_char)'\221', (u_char)'\222', (u_char)'\223',
3179           (u_char)'\224', (u_char)'\225', (u_char)'\226', (u_char)'\227',
3180           (u_char)'\230', (u_char)'\231', (u_char)'\232', (u_char)'\233',
3181           (u_char)'\234', (u_char)'\235', (u_char)'\236', (u_char)'\237',
3182           (u_char)'\240', (u_char)'\241', (u_char)'\242', (u_char)'\243',
3183           (u_char)'\244', (u_char)'\245', (u_char)'\246', (u_char)'\247',
3184           (u_char)'\250', (u_char)'\251', (u_char)'\252', (u_char)'\253',
3185           (u_char)'\254', (u_char)'\255', (u_char)'\256', (u_char)'\257',
3186           (u_char)'\260', (u_char)'\261', (u_char)'\262', (u_char)'\263',
3187           (u_char)'\264', (u_char)'\265', (u_char)'\266', (u_char)'\267',
3188           (u_char)'\270', (u_char)'\271', (u_char)'\272', (u_char)'\273',
3189           (u_char)'\274', (u_char)'\275', (u_char)'\276', (u_char)'\277',
3190           (u_char)'\300', (u_char)'\341', (u_char)'\342', (u_char)'\343',
3191           (u_char)'\344', (u_char)'\345', (u_char)'\346', (u_char)'\347',
3192           (u_char)'\350', (u_char)'\351', (u_char)'\352', (u_char)'\353',
3193           (u_char)'\354', (u_char)'\355', (u_char)'\356', (u_char)'\357',
3194           (u_char)'\360', (u_char)'\361', (u_char)'\362', (u_char)'\363',
3195           (u_char)'\364', (u_char)'\365', (u_char)'\366', (u_char)'\367',
3196           (u_char)'\370', (u_char)'\371', (u_char)'\372', (u_char)'\333',
3197           (u_char)'\334', (u_char)'\335', (u_char)'\336', (u_char)'\337',
3198           (u_char)'\340', (u_char)'\341', (u_char)'\342', (u_char)'\343',
3199           (u_char)'\344', (u_char)'\345', (u_char)'\346', (u_char)'\347',
3200           (u_char)'\350', (u_char)'\351', (u_char)'\352', (u_char)'\353',
3201           (u_char)'\354', (u_char)'\355', (u_char)'\356', (u_char)'\357',
3202           (u_char)'\360', (u_char)'\361', (u_char)'\362', (u_char)'\363',
3203           (u_char)'\364', (u_char)'\365', (u_char)'\366', (u_char)'\367',
3204           (u_char)'\370', (u_char)'\371', (u_char)'\372', (u_char)'\373',
3205           (u_char)'\374', (u_char)'\375', (u_char)'\376', (u_char)'\377',
3206 };
3207 
3208 int
3209 pcapint_strcasecmp(const char *s1, const char *s2)
3210 {
3211           register const u_char         *cm = charmap,
3212                                         *us1 = (const u_char *)s1,
3213                                         *us2 = (const u_char *)s2;
3214 
3215           while (cm[*us1] == cm[*us2++])
3216                     if (*us1++ == '\0')
3217                               return(0);
3218           return (cm[*us1] - cm[*--us2]);
3219 }
3220 
3221 struct dlt_choice {
3222           const char *name;
3223           const char *description;
3224           int       dlt;
3225 };
3226 
3227 #define DLT_CHOICE(code, description) { #code, description, DLT_ ## code }
3228 #define DLT_CHOICE_SENTINEL { NULL, NULL, 0 }
3229 
3230 static struct dlt_choice dlt_choices[] = {
3231           DLT_CHOICE(NULL, "BSD loopback"),
3232           DLT_CHOICE(EN10MB, "Ethernet"),
3233           DLT_CHOICE(IEEE802, "Token ring"),
3234           DLT_CHOICE(ARCNET, "BSD ARCNET"),
3235           DLT_CHOICE(SLIP, "SLIP"),
3236           DLT_CHOICE(PPP, "PPP"),
3237           DLT_CHOICE(FDDI, "FDDI"),
3238           DLT_CHOICE(ATM_RFC1483, "RFC 1483 LLC-encapsulated ATM"),
3239           DLT_CHOICE(RAW, "Raw IP"),
3240           DLT_CHOICE(SLIP_BSDOS, "BSD/OS SLIP"),
3241           DLT_CHOICE(PPP_BSDOS, "BSD/OS PPP"),
3242           DLT_CHOICE(ATM_CLIP, "Linux Classical IP over ATM"),
3243           DLT_CHOICE(PPP_SERIAL, "PPP over serial"),
3244           DLT_CHOICE(PPP_ETHER, "PPPoE"),
3245           DLT_CHOICE(SYMANTEC_FIREWALL, "Symantec Firewall"),
3246           DLT_CHOICE(C_HDLC, "Cisco HDLC"),
3247           DLT_CHOICE(IEEE802_11, "802.11"),
3248           DLT_CHOICE(FRELAY, "Frame Relay"),
3249           DLT_CHOICE(LOOP, "OpenBSD loopback"),
3250           DLT_CHOICE(ENC, "OpenBSD encapsulated IP"),
3251           DLT_CHOICE(LINUX_SLL, "Linux cooked v1"),
3252           DLT_CHOICE(LTALK, "Localtalk"),
3253           DLT_CHOICE(PFLOG, "OpenBSD pflog file"),
3254           DLT_CHOICE(PFSYNC, "Packet filter state syncing"),
3255           DLT_CHOICE(PRISM_HEADER, "802.11 plus Prism header"),
3256           DLT_CHOICE(IP_OVER_FC, "RFC 2625 IP-over-Fibre Channel"),
3257           DLT_CHOICE(SUNATM, "Sun raw ATM"),
3258           DLT_CHOICE(IEEE802_11_RADIO, "802.11 plus radiotap header"),
3259           DLT_CHOICE(ARCNET_LINUX, "Linux ARCNET"),
3260           DLT_CHOICE(JUNIPER_MLPPP, "Juniper Multi-Link PPP"),
3261           DLT_CHOICE(JUNIPER_MLFR, "Juniper Multi-Link Frame Relay"),
3262           DLT_CHOICE(JUNIPER_ES, "Juniper Encryption Services PIC"),
3263           DLT_CHOICE(JUNIPER_GGSN, "Juniper GGSN PIC"),
3264           DLT_CHOICE(JUNIPER_MFR, "Juniper FRF.16 Frame Relay"),
3265           DLT_CHOICE(JUNIPER_ATM2, "Juniper ATM2 PIC"),
3266           DLT_CHOICE(JUNIPER_SERVICES, "Juniper Advanced Services PIC"),
3267           DLT_CHOICE(JUNIPER_ATM1, "Juniper ATM1 PIC"),
3268           DLT_CHOICE(APPLE_IP_OVER_IEEE1394, "Apple IP-over-IEEE 1394"),
3269           DLT_CHOICE(MTP2_WITH_PHDR, "SS7 MTP2 with Pseudo-header"),
3270           DLT_CHOICE(MTP2, "SS7 MTP2"),
3271           DLT_CHOICE(MTP3, "SS7 MTP3"),
3272           DLT_CHOICE(SCCP, "SS7 SCCP"),
3273           DLT_CHOICE(DOCSIS, "DOCSIS"),
3274           DLT_CHOICE(LINUX_IRDA, "Linux IrDA"),
3275           DLT_CHOICE(IEEE802_11_RADIO_AVS, "802.11 plus AVS radio information header"),
3276           DLT_CHOICE(JUNIPER_MONITOR, "Juniper Passive Monitor PIC"),
3277           DLT_CHOICE(BACNET_MS_TP, "BACnet MS/TP"),
3278           DLT_CHOICE(PPP_PPPD, "PPP for pppd, with direction flag"),
3279           DLT_CHOICE(JUNIPER_PPPOE, "Juniper PPPoE"),
3280           DLT_CHOICE(JUNIPER_PPPOE_ATM, "Juniper PPPoE/ATM"),
3281           DLT_CHOICE(GPRS_LLC, "GPRS LLC"),
3282           DLT_CHOICE(GPF_T, "GPF-T"),
3283           DLT_CHOICE(GPF_F, "GPF-F"),
3284           DLT_CHOICE(JUNIPER_PIC_PEER, "Juniper PIC Peer"),
3285           DLT_CHOICE(ERF_ETH, "Ethernet with Endace ERF header"),
3286           DLT_CHOICE(ERF_POS, "Packet-over-SONET with Endace ERF header"),
3287           DLT_CHOICE(LINUX_LAPD, "Linux vISDN LAPD"),
3288           DLT_CHOICE(JUNIPER_ETHER, "Juniper Ethernet"),
3289           DLT_CHOICE(JUNIPER_PPP, "Juniper PPP"),
3290           DLT_CHOICE(JUNIPER_FRELAY, "Juniper Frame Relay"),
3291           DLT_CHOICE(JUNIPER_CHDLC, "Juniper C-HDLC"),
3292           DLT_CHOICE(MFR, "FRF.16 Frame Relay"),
3293           DLT_CHOICE(JUNIPER_VP, "Juniper Voice PIC"),
3294           DLT_CHOICE(A429, "Arinc 429"),
3295           DLT_CHOICE(A653_ICM, "Arinc 653 Interpartition Communication"),
3296           DLT_CHOICE(USB_FREEBSD, "USB with FreeBSD header"),
3297           DLT_CHOICE(BLUETOOTH_HCI_H4, "Bluetooth HCI UART transport layer"),
3298           DLT_CHOICE(IEEE802_16_MAC_CPS, "IEEE 802.16 MAC Common Part Sublayer"),
3299           DLT_CHOICE(USB_LINUX, "USB with Linux header"),
3300           DLT_CHOICE(CAN20B, "Controller Area Network (CAN) v. 2.0B"),
3301           DLT_CHOICE(IEEE802_15_4_LINUX, "IEEE 802.15.4 with Linux padding"),
3302           DLT_CHOICE(PPI, "Per-Packet Information"),
3303           DLT_CHOICE(IEEE802_16_MAC_CPS_RADIO, "IEEE 802.16 MAC Common Part Sublayer plus radiotap header"),
3304           DLT_CHOICE(JUNIPER_ISM, "Juniper Integrated Service Module"),
3305           DLT_CHOICE(IEEE802_15_4, "IEEE 802.15.4 with FCS"),
3306           DLT_CHOICE(SITA, "SITA pseudo-header"),
3307           DLT_CHOICE(ERF, "Endace ERF header"),
3308           DLT_CHOICE(RAIF1, "Ethernet with u10 Networks pseudo-header"),
3309           DLT_CHOICE(IPMB_KONTRON, "IPMB with Kontron pseudo-header"),
3310           DLT_CHOICE(JUNIPER_ST, "Juniper Secure Tunnel"),
3311           DLT_CHOICE(BLUETOOTH_HCI_H4_WITH_PHDR, "Bluetooth HCI UART transport layer plus pseudo-header"),
3312           DLT_CHOICE(AX25_KISS, "AX.25 with KISS header"),
3313           DLT_CHOICE(IPMB_LINUX, "IPMB with Linux/Pigeon Point pseudo-header"),
3314           DLT_CHOICE(IEEE802_15_4_NONASK_PHY, "IEEE 802.15.4 with non-ASK PHY data"),
3315           DLT_CHOICE(MPLS, "MPLS with label as link-layer header"),
3316           DLT_CHOICE(LINUX_EVDEV, "Linux evdev events"),
3317           DLT_CHOICE(USB_LINUX_MMAPPED, "USB with padded Linux header"),
3318           DLT_CHOICE(DECT, "DECT"),
3319           DLT_CHOICE(AOS, "AOS Space Data Link protocol"),
3320           DLT_CHOICE(WIHART, "WirelessHART"),
3321           DLT_CHOICE(FC_2, "Fibre Channel FC-2"),
3322           DLT_CHOICE(FC_2_WITH_FRAME_DELIMS, "Fibre Channel FC-2 with frame delimiters"),
3323           DLT_CHOICE(IPNET, "Solaris ipnet"),
3324           DLT_CHOICE(CAN_SOCKETCAN, "CAN-bus with SocketCAN headers"),
3325           DLT_CHOICE(IPV4, "Raw IPv4"),
3326           DLT_CHOICE(IPV6, "Raw IPv6"),
3327           DLT_CHOICE(IEEE802_15_4_NOFCS, "IEEE 802.15.4 without FCS"),
3328           DLT_CHOICE(DBUS, "D-Bus"),
3329           DLT_CHOICE(JUNIPER_VS, "Juniper Virtual Server"),
3330           DLT_CHOICE(JUNIPER_SRX_E2E, "Juniper SRX E2E"),
3331           DLT_CHOICE(JUNIPER_FIBRECHANNEL, "Juniper Fibre Channel"),
3332           DLT_CHOICE(DVB_CI, "DVB-CI"),
3333           DLT_CHOICE(MUX27010, "MUX27010"),
3334           DLT_CHOICE(STANAG_5066_D_PDU, "STANAG 5066 D_PDUs"),
3335           DLT_CHOICE(JUNIPER_ATM_CEMIC, "Juniper ATM CEMIC"),
3336           DLT_CHOICE(NFLOG, "Linux netfilter log messages"),
3337           DLT_CHOICE(NETANALYZER, "Ethernet with Hilscher netANALYZER pseudo-header"),
3338           DLT_CHOICE(NETANALYZER_TRANSPARENT, "Ethernet with Hilscher netANALYZER pseudo-header and with preamble and SFD"),
3339           DLT_CHOICE(IPOIB, "RFC 4391 IP-over-Infiniband"),
3340           DLT_CHOICE(MPEG_2_TS, "MPEG-2 transport stream"),
3341           DLT_CHOICE(NG40, "ng40 protocol tester Iub/Iur"),
3342           DLT_CHOICE(NFC_LLCP, "NFC LLCP PDUs with pseudo-header"),
3343           DLT_CHOICE(INFINIBAND, "InfiniBand"),
3344           DLT_CHOICE(SCTP, "SCTP"),
3345           DLT_CHOICE(USBPCAP, "USB with USBPcap header"),
3346           DLT_CHOICE(RTAC_SERIAL, "Schweitzer Engineering Laboratories RTAC packets"),
3347           DLT_CHOICE(BLUETOOTH_LE_LL, "Bluetooth Low Energy air interface"),
3348           DLT_CHOICE(NETLINK, "Linux netlink"),
3349           DLT_CHOICE(BLUETOOTH_LINUX_MONITOR, "Bluetooth Linux Monitor"),
3350           DLT_CHOICE(BLUETOOTH_BREDR_BB, "Bluetooth Basic Rate/Enhanced Data Rate baseband packets"),
3351           DLT_CHOICE(BLUETOOTH_LE_LL_WITH_PHDR, "Bluetooth Low Energy air interface with pseudo-header"),
3352           DLT_CHOICE(PROFIBUS_DL, "PROFIBUS data link layer"),
3353           DLT_CHOICE(PKTAP, "Apple DLT_PKTAP"),
3354           DLT_CHOICE(EPON, "Ethernet with 802.3 Clause 65 EPON preamble"),
3355           DLT_CHOICE(IPMI_HPM_2, "IPMI trace packets"),
3356           DLT_CHOICE(ZWAVE_R1_R2, "Z-Wave RF profile R1 and R2 packets"),
3357           DLT_CHOICE(ZWAVE_R3, "Z-Wave RF profile R3 packets"),
3358           DLT_CHOICE(WATTSTOPPER_DLM, "WattStopper Digital Lighting Management (DLM) and Legrand Nitoo Open protocol"),
3359           DLT_CHOICE(ISO_14443, "ISO 14443 messages"),
3360           DLT_CHOICE(RDS, "IEC 62106 Radio Data System groups"),
3361           DLT_CHOICE(USB_DARWIN, "USB with Darwin header"),
3362           DLT_CHOICE(OPENFLOW, "OpenBSD DLT_OPENFLOW"),
3363           DLT_CHOICE(SDLC, "IBM SDLC frames"),
3364           DLT_CHOICE(TI_LLN_SNIFFER, "TI LLN sniffer frames"),
3365           DLT_CHOICE(VSOCK, "Linux vsock"),
3366           DLT_CHOICE(NORDIC_BLE, "Nordic Semiconductor Bluetooth LE sniffer frames"),
3367           DLT_CHOICE(DOCSIS31_XRA31, "Excentis XRA-31 DOCSIS 3.1 RF sniffer frames"),
3368           DLT_CHOICE(ETHERNET_MPACKET, "802.3br mPackets"),
3369           DLT_CHOICE(DISPLAYPORT_AUX, "DisplayPort AUX channel monitoring data"),
3370           DLT_CHOICE(LINUX_SLL2, "Linux cooked v2"),
3371           DLT_CHOICE(OPENVIZSLA, "OpenVizsla USB"),
3372           DLT_CHOICE(EBHSCR, "Elektrobit High Speed Capture and Replay (EBHSCR)"),
3373           DLT_CHOICE(VPP_DISPATCH, "VPP graph dispatch tracer"),
3374           DLT_CHOICE(DSA_TAG_BRCM, "Broadcom tag"),
3375           DLT_CHOICE(DSA_TAG_BRCM_PREPEND, "Broadcom tag (prepended)"),
3376           DLT_CHOICE(IEEE802_15_4_TAP, "IEEE 802.15.4 with pseudo-header"),
3377           DLT_CHOICE(DSA_TAG_DSA, "Marvell DSA"),
3378           DLT_CHOICE(DSA_TAG_EDSA, "Marvell EDSA"),
3379           DLT_CHOICE(ELEE, "ELEE lawful intercept packets"),
3380           DLT_CHOICE(Z_WAVE_SERIAL, "Z-Wave serial frames between host and chip"),
3381           DLT_CHOICE(USB_2_0, "USB 2.0/1.1/1.0 as transmitted over the cable"),
3382           DLT_CHOICE(ATSC_ALP, "ATSC Link-Layer Protocol packets"),
3383           DLT_CHOICE_SENTINEL
3384 };
3385 
3386 int
3387 pcap_datalink_name_to_val(const char *name)
3388 {
3389           int i;
3390 
3391           for (i = 0; dlt_choices[i].name != NULL; i++) {
3392                     if (pcapint_strcasecmp(dlt_choices[i].name, name) == 0)
3393                               return (dlt_choices[i].dlt);
3394           }
3395           return (-1);
3396 }
3397 
3398 const char *
3399 pcap_datalink_val_to_name(int dlt)
3400 {
3401           int i;
3402 
3403           for (i = 0; dlt_choices[i].name != NULL; i++) {
3404                     if (dlt_choices[i].dlt == dlt)
3405                               return (dlt_choices[i].name);
3406           }
3407           return (NULL);
3408 }
3409 
3410 const char *
3411 pcap_datalink_val_to_description(int dlt)
3412 {
3413           int i;
3414 
3415           for (i = 0; dlt_choices[i].name != NULL; i++) {
3416                     if (dlt_choices[i].dlt == dlt)
3417                               return (dlt_choices[i].description);
3418           }
3419           return (NULL);
3420 }
3421 
3422 const char *
3423 pcap_datalink_val_to_description_or_dlt(int dlt)
3424 {
3425         static thread_local char unkbuf[40];
3426         const char *description;
3427 
3428         description = pcap_datalink_val_to_description(dlt);
3429         if (description != NULL) {
3430                 return description;
3431         } else {
3432                 (void)snprintf(unkbuf, sizeof(unkbuf), "DLT %d", dlt);
3433                 return unkbuf;
3434         }
3435 }
3436 
3437 struct tstamp_type_choice {
3438           const char *name;
3439           const char *description;
3440           int       type;
3441 };
3442 
3443 static struct tstamp_type_choice tstamp_type_choices[] = {
3444           { "host", "Host", PCAP_TSTAMP_HOST },
3445           { "host_lowprec", "Host, low precision", PCAP_TSTAMP_HOST_LOWPREC },
3446           { "host_hiprec", "Host, high precision", PCAP_TSTAMP_HOST_HIPREC },
3447           { "adapter", "Adapter", PCAP_TSTAMP_ADAPTER },
3448           { "adapter_unsynced", "Adapter, not synced with system time", PCAP_TSTAMP_ADAPTER_UNSYNCED },
3449           { "host_hiprec_unsynced", "Host, high precision, not synced with system time", PCAP_TSTAMP_HOST_HIPREC_UNSYNCED },
3450           { NULL, NULL, 0 }
3451 };
3452 
3453 int
3454 pcap_tstamp_type_name_to_val(const char *name)
3455 {
3456           int i;
3457 
3458           for (i = 0; tstamp_type_choices[i].name != NULL; i++) {
3459                     if (pcapint_strcasecmp(tstamp_type_choices[i].name, name) == 0)
3460                               return (tstamp_type_choices[i].type);
3461           }
3462           return (PCAP_ERROR);
3463 }
3464 
3465 const char *
3466 pcap_tstamp_type_val_to_name(int tstamp_type)
3467 {
3468           int i;
3469 
3470           for (i = 0; tstamp_type_choices[i].name != NULL; i++) {
3471                     if (tstamp_type_choices[i].type == tstamp_type)
3472                               return (tstamp_type_choices[i].name);
3473           }
3474           return (NULL);
3475 }
3476 
3477 const char *
3478 pcap_tstamp_type_val_to_description(int tstamp_type)
3479 {
3480           int i;
3481 
3482           for (i = 0; tstamp_type_choices[i].name != NULL; i++) {
3483                     if (tstamp_type_choices[i].type == tstamp_type)
3484                               return (tstamp_type_choices[i].description);
3485           }
3486           return (NULL);
3487 }
3488 
3489 int
3490 pcap_snapshot(pcap_t *p)
3491 {
3492           if (!p->activated)
3493                     return (PCAP_ERROR_NOT_ACTIVATED);
3494           return (p->snapshot);
3495 }
3496 
3497 int
3498 pcap_is_swapped(pcap_t *p)
3499 {
3500           if (!p->activated)
3501                     return (PCAP_ERROR_NOT_ACTIVATED);
3502           return (p->swapped);
3503 }
3504 
3505 int
3506 pcap_major_version(pcap_t *p)
3507 {
3508           if (!p->activated)
3509                     return (PCAP_ERROR_NOT_ACTIVATED);
3510           return (p->version_major);
3511 }
3512 
3513 int
3514 pcap_minor_version(pcap_t *p)
3515 {
3516           if (!p->activated)
3517                     return (PCAP_ERROR_NOT_ACTIVATED);
3518           return (p->version_minor);
3519 }
3520 
3521 int
3522 pcap_bufsize(pcap_t *p)
3523 {
3524           if (!p->activated)
3525                     return (PCAP_ERROR_NOT_ACTIVATED);
3526           return (p->bufsize);
3527 }
3528 
3529 FILE *
3530 pcap_file(pcap_t *p)
3531 {
3532           return (p->rfile);
3533 }
3534 
3535 #ifdef _WIN32
3536 int
3537 pcap_fileno(pcap_t *p)
3538 {
3539           if (p->handle != INVALID_HANDLE_VALUE) {
3540                     /*
3541                      * This is a bogus and now-deprecated API; we
3542                      * squelch the narrowing warning for the cast
3543                      * from HANDLE to intptr_t.  If Windows programmers
3544                      * need to get at the HANDLE for a pcap_t, *if*
3545                      * there is one, they should request such a
3546                      * routine (and be prepared for it to return
3547                      * INVALID_HANDLE_VALUE).
3548                      */
3549 DIAG_OFF_NARROWING
3550                     return ((int)(intptr_t)p->handle);
3551 DIAG_ON_NARROWING
3552           } else
3553                     return (PCAP_ERROR);
3554 }
3555 #else /* _WIN32 */
3556 int
3557 pcap_fileno(pcap_t *p)
3558 {
3559           return (p->fd);
3560 }
3561 #endif /* _WIN32 */
3562 
3563 #if !defined(_WIN32) && !defined(MSDOS)
3564 int
3565 pcap_get_selectable_fd(pcap_t *p)
3566 {
3567           return (p->selectable_fd);
3568 }
3569 
3570 const struct timeval *
3571 pcap_get_required_select_timeout(pcap_t *p)
3572 {
3573           return (p->required_select_timeout);
3574 }
3575 #endif
3576 
3577 void
3578 pcap_perror(pcap_t *p, const char *prefix)
3579 {
3580           fprintf(stderr, "%s: %s\n", prefix, p->errbuf);
3581 }
3582 
3583 char *
3584 pcap_geterr(pcap_t *p)
3585 {
3586           return (p->errbuf);
3587 }
3588 
3589 int
3590 pcap_getnonblock(pcap_t *p, char *errbuf)
3591 {
3592           int ret;
3593 
3594           ret = p->getnonblock_op(p);
3595           if (ret == -1) {
3596                     /*
3597                      * The get nonblock operation sets p->errbuf; this
3598                      * function *shouldn't* have had a separate errbuf
3599                      * argument, as it didn't need one, but I goofed
3600                      * when adding it.
3601                      *
3602                      * We copy the error message to errbuf, so callers
3603                      * can find it in either place.
3604                      */
3605                     pcapint_strlcpy(errbuf, p->errbuf, PCAP_ERRBUF_SIZE);
3606           }
3607           return (ret);
3608 }
3609 
3610 /*
3611  * Get the current non-blocking mode setting, under the assumption that
3612  * it's just the standard POSIX non-blocking flag.
3613  */
3614 #if !defined(_WIN32) && !defined(MSDOS)
3615 int
3616 pcapint_getnonblock_fd(pcap_t *p)
3617 {
3618           int fdflags;
3619 
3620           fdflags = fcntl(p->fd, F_GETFL, 0);
3621           if (fdflags == -1) {
3622                     pcapint_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
3623                         errno, "F_GETFL");
3624                     return (-1);
3625           }
3626           if (fdflags & O_NONBLOCK)
3627                     return (1);
3628           else
3629                     return (0);
3630 }
3631 #endif
3632 
3633 int
3634 pcap_setnonblock(pcap_t *p, int nonblock, char *errbuf)
3635 {
3636           int ret;
3637 
3638           ret = p->setnonblock_op(p, nonblock);
3639           if (ret == -1) {
3640                     /*
3641                      * The set nonblock operation sets p->errbuf; this
3642                      * function *shouldn't* have had a separate errbuf
3643                      * argument, as it didn't need one, but I goofed
3644                      * when adding it.
3645                      *
3646                      * We copy the error message to errbuf, so callers
3647                      * can find it in either place.
3648                      */
3649                     pcapint_strlcpy(errbuf, p->errbuf, PCAP_ERRBUF_SIZE);
3650           }
3651           return (ret);
3652 }
3653 
3654 #if !defined(_WIN32) && !defined(MSDOS)
3655 /*
3656  * Set non-blocking mode, under the assumption that it's just the
3657  * standard POSIX non-blocking flag.  (This can be called by the
3658  * per-platform non-blocking-mode routine if that routine also
3659  * needs to do some additional work.)
3660  */
3661 int
3662 pcapint_setnonblock_fd(pcap_t *p, int nonblock)
3663 {
3664           int fdflags;
3665 
3666           fdflags = fcntl(p->fd, F_GETFL, 0);
3667           if (fdflags == -1) {
3668                     pcapint_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
3669                         errno, "F_GETFL");
3670                     return (-1);
3671           }
3672           if (nonblock)
3673                     fdflags |= O_NONBLOCK;
3674           else
3675                     fdflags &= ~O_NONBLOCK;
3676           if (fcntl(p->fd, F_SETFL, fdflags) == -1) {
3677                     pcapint_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
3678                         errno, "F_SETFL");
3679                     return (-1);
3680           }
3681           return (0);
3682 }
3683 #endif
3684 
3685 /*
3686  * Generate error strings for PCAP_ERROR_ and PCAP_WARNING_ values.
3687  */
3688 const char *
3689 pcap_statustostr(int errnum)
3690 {
3691           static thread_local char ebuf[15+10+1];
3692 
3693           switch (errnum) {
3694 
3695           case PCAP_WARNING:
3696                     return("Generic warning");
3697 
3698           case PCAP_WARNING_TSTAMP_TYPE_NOTSUP:
3699                     return ("That type of time stamp is not supported by that device");
3700 
3701           case PCAP_WARNING_PROMISC_NOTSUP:
3702                     return ("That device doesn't support promiscuous mode");
3703 
3704           case PCAP_ERROR:
3705                     return("Generic error");
3706 
3707           case PCAP_ERROR_BREAK:
3708                     return("Loop terminated by pcap_breakloop");
3709 
3710           case PCAP_ERROR_NOT_ACTIVATED:
3711                     return("The pcap_t has not been activated");
3712 
3713           case PCAP_ERROR_ACTIVATED:
3714                     return ("The setting can't be changed after the pcap_t is activated");
3715 
3716           case PCAP_ERROR_NO_SUCH_DEVICE:
3717                     return ("No such device exists");
3718 
3719           case PCAP_ERROR_RFMON_NOTSUP:
3720                     return ("That device doesn't support monitor mode");
3721 
3722           case PCAP_ERROR_NOT_RFMON:
3723                     return ("That operation is supported only in monitor mode");
3724 
3725           case PCAP_ERROR_PERM_DENIED:
3726                     return ("You don't have permission to perform this capture on that device");
3727 
3728           case PCAP_ERROR_IFACE_NOT_UP:
3729                     return ("That device is not up");
3730 
3731           case PCAP_ERROR_CANTSET_TSTAMP_TYPE:
3732                     return ("That device doesn't support setting the time stamp type");
3733 
3734           case PCAP_ERROR_PROMISC_PERM_DENIED:
3735                     return ("You don't have permission to capture in promiscuous mode on that device");
3736 
3737           case PCAP_ERROR_TSTAMP_PRECISION_NOTSUP:
3738                     return ("That device doesn't support that time stamp precision");
3739 
3740           case PCAP_ERROR_CAPTURE_NOTSUP:
3741                     return ("Packet capture is not supported on that device");
3742           }
3743           (void)snprintf(ebuf, sizeof ebuf, "Unknown error: %d", errnum);
3744           return(ebuf);
3745 }
3746 
3747 /*
3748  * A long time ago the purpose of this function was to hide the difference
3749  * between those Unix-like OSes that implemented strerror() and those that
3750  * didn't.  All the currently supported OSes implement strerror(), which is in
3751  * POSIX.1-2001, uniformly and that particular problem no longer exists.  But
3752  * now they implement a few incompatible thread-safe variants of strerror(),
3753  * and hiding that difference is the current purpose of this function.
3754  */
3755 const char *
3756 pcap_strerror(int errnum)
3757 {
3758 #ifdef _WIN32
3759           static thread_local char errbuf[PCAP_ERRBUF_SIZE];
3760           errno_t err = strerror_s(errbuf, PCAP_ERRBUF_SIZE, errnum);
3761 
3762           if (err != 0) /* err = 0 if successful */
3763                     pcapint_strlcpy(errbuf, "strerror_s() error", PCAP_ERRBUF_SIZE);
3764           return (errbuf);
3765 #elif defined(HAVE_GNU_STRERROR_R)
3766           /*
3767            * We have a GNU-style strerror_r(), which is *not* guaranteed to
3768            * do anything to the buffer handed to it, and which returns a
3769            * pointer to the error string, which may or may not be in
3770            * the buffer.
3771            *
3772            * It is, however, guaranteed to succeed.
3773            *
3774            * At the time of this writing this applies to the following cases,
3775            * each of which allows to use either the GNU implementation or the
3776            * POSIX implementation, and this source tree defines _GNU_SOURCE to
3777            * use the GNU implementation:
3778            * - Hurd
3779            * - Linux with GNU libc
3780            * - Linux with uClibc-ng
3781            */
3782           static thread_local char errbuf[PCAP_ERRBUF_SIZE];
3783           return strerror_r(errnum, errbuf, PCAP_ERRBUF_SIZE);
3784 #elif defined(HAVE_POSIX_STRERROR_R)
3785           /*
3786            * We have a POSIX-style strerror_r(), which is guaranteed to fill
3787            * in the buffer, but is not guaranteed to succeed.
3788            *
3789            * At the time of this writing this applies to the following cases:
3790            * - AIX 7
3791            * - FreeBSD
3792            * - Haiku
3793            * - HP-UX 11
3794            * - illumos
3795            * - Linux with musl libc
3796            * - macOS
3797            * - NetBSD
3798            * - OpenBSD
3799            * - Solaris 10 & 11
3800            */
3801           static thread_local char errbuf[PCAP_ERRBUF_SIZE];
3802           int err = strerror_r(errnum, errbuf, PCAP_ERRBUF_SIZE);
3803           switch (err) {
3804           case 0:
3805                     /* That worked. */
3806                     break;
3807 
3808           case EINVAL:
3809                     /*
3810                      * UNIX 03 says this isn't guaranteed to produce a
3811                      * fallback error message.
3812                      */
3813                     snprintf(errbuf, PCAP_ERRBUF_SIZE,
3814                              "Unknown error: %d", errnum);
3815                     break;
3816           case ERANGE:
3817                     /*
3818                      * UNIX 03 says this isn't guaranteed to produce a
3819                      * fallback error message.
3820                      */
3821                     snprintf(errbuf, PCAP_ERRBUF_SIZE,
3822                              "Message for error %d is too long", errnum);
3823                     break;
3824           default:
3825                     snprintf(errbuf, PCAP_ERRBUF_SIZE,
3826                              "strerror_r(%d, ...) unexpectedly returned %d",
3827                              errnum, err);
3828           }
3829           return errbuf;
3830 #else
3831           /*
3832            * At the time of this writing every supported OS implements strerror()
3833            * and at least one thread-safe variant thereof, so this is a very
3834            * unlikely last-resort branch.  Particular implementations of strerror()
3835            * may be thread-safe, but this is neither required nor guaranteed.
3836            */
3837           return (strerror(errnum));
3838 #endif /* _WIN32 */
3839 }
3840 
3841 int
3842 pcap_setfilter(pcap_t *p, struct bpf_program *fp)
3843 {
3844           return (p->setfilter_op(p, fp));
3845 }
3846 
3847 /*
3848  * Set direction flag, which controls whether we accept only incoming
3849  * packets, only outgoing packets, or both.
3850  * Note that, depending on the platform, some or all direction arguments
3851  * might not be supported.
3852  */
3853 int
3854 pcap_setdirection(pcap_t *p, pcap_direction_t d)
3855 {
3856           if (p->setdirection_op == NULL) {
3857                     snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
3858                         "Setting direction is not supported on this device");
3859                     return (-1);
3860           } else {
3861                     switch (d) {
3862 
3863                     case PCAP_D_IN:
3864                     case PCAP_D_OUT:
3865                     case PCAP_D_INOUT:
3866                               /*
3867                                * Valid direction.
3868                                */
3869                               return (p->setdirection_op(p, d));
3870 
3871                     default:
3872                               /*
3873                                * Invalid direction.
3874                                */
3875                               snprintf(p->errbuf, sizeof(p->errbuf),
3876                                   "Invalid direction");
3877                               return (-1);
3878                     }
3879           }
3880 }
3881 
3882 int
3883 pcap_stats(pcap_t *p, struct pcap_stat *ps)
3884 {
3885           return (p->stats_op(p, ps));
3886 }
3887 
3888 #ifdef _WIN32
3889 struct pcap_stat *
3890 pcap_stats_ex(pcap_t *p, int *pcap_stat_size)
3891 {
3892           return (p->stats_ex_op(p, pcap_stat_size));
3893 }
3894 
3895 int
3896 pcap_setbuff(pcap_t *p, int dim)
3897 {
3898           return (p->setbuff_op(p, dim));
3899 }
3900 
3901 int
3902 pcap_setmode(pcap_t *p, int mode)
3903 {
3904           return (p->setmode_op(p, mode));
3905 }
3906 
3907 int
3908 pcap_setmintocopy(pcap_t *p, int size)
3909 {
3910           return (p->setmintocopy_op(p, size));
3911 }
3912 
3913 HANDLE
3914 pcap_getevent(pcap_t *p)
3915 {
3916           return (p->getevent_op(p));
3917 }
3918 
3919 int
3920 pcap_oid_get_request(pcap_t *p, bpf_u_int32 oid, void *data, size_t *lenp)
3921 {
3922           return (p->oid_get_request_op(p, oid, data, lenp));
3923 }
3924 
3925 int
3926 pcap_oid_set_request(pcap_t *p, bpf_u_int32 oid, const void *data, size_t *lenp)
3927 {
3928           return (p->oid_set_request_op(p, oid, data, lenp));
3929 }
3930 
3931 pcap_send_queue *
3932 pcap_sendqueue_alloc(u_int memsize)
3933 {
3934           pcap_send_queue *tqueue;
3935 
3936           /* Allocate the queue */
3937           tqueue = (pcap_send_queue *)malloc(sizeof(pcap_send_queue));
3938           if (tqueue == NULL){
3939                     return (NULL);
3940           }
3941 
3942           /* Allocate the buffer */
3943           tqueue->buffer = (char *)malloc(memsize);
3944           if (tqueue->buffer == NULL) {
3945                     free(tqueue);
3946                     return (NULL);
3947           }
3948 
3949           tqueue->maxlen = memsize;
3950           tqueue->len = 0;
3951 
3952           return (tqueue);
3953 }
3954 
3955 void
3956 pcap_sendqueue_destroy(pcap_send_queue *queue)
3957 {
3958           free(queue->buffer);
3959           free(queue);
3960 }
3961 
3962 int
3963 pcap_sendqueue_queue(pcap_send_queue *queue, const struct pcap_pkthdr *pkt_header, const u_char *pkt_data)
3964 {
3965           if (queue->len + sizeof(struct pcap_pkthdr) + pkt_header->caplen > queue->maxlen){
3966                     return (-1);
3967           }
3968 
3969           /* Copy the pcap_pkthdr header*/
3970           memcpy(queue->buffer + queue->len, pkt_header, sizeof(struct pcap_pkthdr));
3971           queue->len += sizeof(struct pcap_pkthdr);
3972 
3973           /* copy the packet */
3974           memcpy(queue->buffer + queue->len, pkt_data, pkt_header->caplen);
3975           queue->len += pkt_header->caplen;
3976 
3977           return (0);
3978 }
3979 
3980 u_int
3981 pcap_sendqueue_transmit(pcap_t *p, pcap_send_queue *queue, int sync)
3982 {
3983           return (p->sendqueue_transmit_op(p, queue, sync));
3984 }
3985 
3986 int
3987 pcap_setuserbuffer(pcap_t *p, int size)
3988 {
3989           return (p->setuserbuffer_op(p, size));
3990 }
3991 
3992 int
3993 pcap_live_dump(pcap_t *p, char *filename, int maxsize, int maxpacks)
3994 {
3995           return (p->live_dump_op(p, filename, maxsize, maxpacks));
3996 }
3997 
3998 int
3999 pcap_live_dump_ended(pcap_t *p, int sync)
4000 {
4001           return (p->live_dump_ended_op(p, sync));
4002 }
4003 
4004 PAirpcapHandle
4005 pcap_get_airpcap_handle(pcap_t *p)
4006 {
4007           PAirpcapHandle handle;
4008 
4009           handle = p->get_airpcap_handle_op(p);
4010           if (handle == NULL) {
4011                     (void)snprintf(p->errbuf, sizeof(p->errbuf),
4012                         "This isn't an AirPcap device");
4013           }
4014           return (handle);
4015 }
4016 #endif
4017 
4018 /*
4019  * On some platforms, we need to clean up promiscuous or monitor mode
4020  * when we close a device - and we want that to happen even if the
4021  * application just exits without explicitly closing devices.
4022  * On those platforms, we need to register a "close all the pcaps"
4023  * routine to be called when we exit, and need to maintain a list of
4024  * pcaps that need to be closed to clean up modes.
4025  *
4026  * XXX - not thread-safe.
4027  */
4028 
4029 /*
4030  * List of pcaps on which we've done something that needs to be
4031  * cleaned up.
4032  * If there are any such pcaps, we arrange to call "pcap_close_all()"
4033  * when we exit, and have it close all of them.
4034  */
4035 static struct pcap *pcaps_to_close;
4036 
4037 /*
4038  * TRUE if we've already called "atexit()" to cause "pcap_close_all()" to
4039  * be called on exit.
4040  */
4041 static int did_atexit;
4042 
4043 static void
4044 pcap_close_all(void)
4045 {
4046           struct pcap *handle;
4047 
4048           while ((handle = pcaps_to_close) != NULL) {
4049                     pcap_close(handle);
4050 
4051                     /*
4052                      * If a pcap module adds a pcap_t to the "close all"
4053                      * list by calling pcapint_add_to_pcaps_to_close(), it
4054                      * must have a cleanup routine that removes it from the
4055                      * list, by calling pcapint_remove_from_pcaps_to_close(),
4056                      * and must make that cleanup routine the cleanup_op
4057                      * for the pcap_t.
4058                      *
4059                      * That means that, after pcap_close() - which calls
4060                      * the cleanup_op for the pcap_t - the pcap_t must
4061                      * have been removed from the list, so pcaps_to_close
4062                      * must not be equal to handle.
4063                      *
4064                      * We check for that, and abort if handle is still
4065                      * at the head of the list, to prevent infinite loops.
4066                      */
4067                     if (pcaps_to_close == handle)
4068                               abort();
4069           }
4070 }
4071 
4072 int
4073 pcapint_do_addexit(pcap_t *p)
4074 {
4075           /*
4076            * If we haven't already done so, arrange to have
4077            * "pcap_close_all()" called when we exit.
4078            */
4079           if (!did_atexit) {
4080                     if (atexit(pcap_close_all) != 0) {
4081                               /*
4082                                * "atexit()" failed; let our caller know.
4083                                */
4084                               pcapint_strlcpy(p->errbuf, "atexit failed", PCAP_ERRBUF_SIZE);
4085                               return (0);
4086                     }
4087                     did_atexit = 1;
4088           }
4089           return (1);
4090 }
4091 
4092 void
4093 pcapint_add_to_pcaps_to_close(pcap_t *p)
4094 {
4095           p->next = pcaps_to_close;
4096           pcaps_to_close = p;
4097 }
4098 
4099 void
4100 pcapint_remove_from_pcaps_to_close(pcap_t *p)
4101 {
4102           pcap_t *pc, *prevpc;
4103 
4104           for (pc = pcaps_to_close, prevpc = NULL; pc != NULL;
4105               prevpc = pc, pc = pc->next) {
4106                     if (pc == p) {
4107                               /*
4108                                * Found it.  Remove it from the list.
4109                                */
4110                               if (prevpc == NULL) {
4111                                         /*
4112                                          * It was at the head of the list.
4113                                          */
4114                                         pcaps_to_close = pc->next;
4115                               } else {
4116                                         /*
4117                                          * It was in the middle of the list.
4118                                          */
4119                                         prevpc->next = pc->next;
4120                               }
4121                               break;
4122                     }
4123           }
4124 }
4125 
4126 void
4127 pcapint_breakloop_common(pcap_t *p)
4128 {
4129           p->break_loop = 1;
4130 }
4131 
4132 
4133 void
4134 pcapint_cleanup_live_common(pcap_t *p)
4135 {
4136           if (p->opt.device != NULL) {
4137                     free(p->opt.device);
4138                     p->opt.device = NULL;
4139           }
4140           if (p->buffer != NULL) {
4141                     free(p->buffer);
4142                     p->buffer = NULL;
4143           }
4144           if (p->dlt_list != NULL) {
4145                     free(p->dlt_list);
4146                     p->dlt_list = NULL;
4147                     p->dlt_count = 0;
4148           }
4149           if (p->tstamp_type_list != NULL) {
4150                     free(p->tstamp_type_list);
4151                     p->tstamp_type_list = NULL;
4152                     p->tstamp_type_count = 0;
4153           }
4154           if (p->tstamp_precision_list != NULL) {
4155                     free(p->tstamp_precision_list);
4156                     p->tstamp_precision_list = NULL;
4157                     p->tstamp_precision_count = 0;
4158           }
4159           pcap_freecode(&p->fcode);
4160 #if !defined(_WIN32) && !defined(MSDOS)
4161           if (p->fd >= 0) {
4162                     close(p->fd);
4163                     p->fd = -1;
4164           }
4165           p->selectable_fd = -1;
4166 #endif
4167 }
4168 
4169 /*
4170  * API compatible with WinPcap's "send a packet" routine - returns -1
4171  * on error, 0 otherwise.
4172  *
4173  * XXX - what if we get a short write?
4174  */
4175 int
4176 pcap_sendpacket(pcap_t *p, const u_char *buf, int size)
4177 {
4178           if (size <= 0) {
4179                     pcapint_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
4180                         errno, "The number of bytes to be sent must be positive");
4181                     return (PCAP_ERROR);
4182           }
4183 
4184           if (p->inject_op(p, buf, size) == -1)
4185                     return (-1);
4186           return (0);
4187 }
4188 
4189 /*
4190  * API compatible with OpenBSD's "send a packet" routine - returns -1 on
4191  * error, number of bytes written otherwise.
4192  */
4193 int
4194 pcap_inject(pcap_t *p, const void *buf, size_t size)
4195 {
4196           /*
4197            * We return the number of bytes written, so the number of
4198            * bytes to write must fit in an int.
4199            */
4200           if (size > INT_MAX) {
4201                     pcapint_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
4202                         errno, "More than %d bytes cannot be injected", INT_MAX);
4203                     return (PCAP_ERROR);
4204           }
4205 
4206           if (size == 0) {
4207                     pcapint_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
4208                         errno, "The number of bytes to be injected must not be zero");
4209                     return (PCAP_ERROR);
4210           }
4211 
4212           return (p->inject_op(p, buf, size));
4213 }
4214 
4215 void
4216 pcap_close(pcap_t *p)
4217 {
4218           p->cleanup_op(p);
4219           free(p);
4220 }
4221 
4222 /*
4223  * Helpers for safely loading code at run time.
4224  * Currently Windows-only.
4225  */
4226 #ifdef _WIN32
4227 //
4228 // This wrapper around loadlibrary appends the system folder (usually
4229 // C:\Windows\System32) to the relative path of the DLL, so that the DLL
4230 // is always loaded from an absolute path (it's no longer possible to
4231 // load modules from the application folder).
4232 // This solves the DLL Hijacking issue discovered in August 2010:
4233 //
4234 // https://blog.rapid7.com/2010/08/23/exploiting-dll-hijacking-flaws/
4235 // https://blog.rapid7.com/2010/08/23/application-dll-load-hijacking/
4236 // (the purported Rapid7 blog post link in the first of those two links
4237 // is broken; the second of those links works.)
4238 //
4239 // If any links there are broken from all the content shuffling Rapid&
4240 // did, see archived versions of the posts at their original homes, at
4241 //
4242 // https://web.archive.org/web/20110122175058/http://blog.metasploit.com/2010/08/exploiting-dll-hijacking-flaws.html
4243 // https://web.archive.org/web/20100828112111/http://blog.rapid7.com/?p=5325
4244 //
4245 pcap_code_handle_t
4246 pcapint_load_code(const char *name)
4247 {
4248           /*
4249            * XXX - should this work in UTF-16LE rather than in the local
4250            * ANSI code page?
4251            */
4252           CHAR path[MAX_PATH];
4253           CHAR fullFileName[MAX_PATH];
4254           UINT res;
4255           HMODULE hModule = NULL;
4256 
4257           do
4258           {
4259                     res = GetSystemDirectoryA(path, MAX_PATH);
4260 
4261                     if (res == 0) {
4262                               //
4263                               // some bad failure occurred;
4264                               //
4265                               break;
4266                     }
4267 
4268                     if (res > MAX_PATH) {
4269                               //
4270                               // the buffer was not big enough
4271                               //
4272                               SetLastError(ERROR_INSUFFICIENT_BUFFER);
4273                               break;
4274                     }
4275 
4276                     if (res + 1 + strlen(name) + 1 < MAX_PATH) {
4277                               memcpy(fullFileName, path, res * sizeof(TCHAR));
4278                               fullFileName[res] = '\\';
4279                               memcpy(&fullFileName[res + 1], name, (strlen(name) + 1) * sizeof(TCHAR));
4280 
4281                               hModule = LoadLibraryA(fullFileName);
4282                     } else
4283                               SetLastError(ERROR_INSUFFICIENT_BUFFER);
4284 
4285           } while(FALSE);
4286 
4287           return hModule;
4288 }
4289 
4290 pcap_funcptr_t
4291 pcapint_find_function(pcap_code_handle_t code, const char *func)
4292 {
4293           return (GetProcAddress(code, func));
4294 }
4295 #endif
4296 
4297 /*
4298  * Given a BPF program, a pcap_pkthdr structure for a packet, and the raw
4299  * data for the packet, check whether the packet passes the filter.
4300  * Returns the return value of the filter program, which will be zero if
4301  * the packet doesn't pass and non-zero if the packet does pass.
4302  */
4303 int
4304 pcap_offline_filter(const struct bpf_program *fp, const struct pcap_pkthdr *h,
4305     const u_char *pkt)
4306 {
4307           const struct bpf_insn *fcode = fp->bf_insns;
4308 
4309           if (fcode != NULL)
4310                     return (pcapint_filter(fcode, pkt, h->len, h->caplen));
4311           else
4312                     return (0);
4313 }
4314 
4315 static int
4316 pcap_can_set_rfmon_dead(pcap_t *p)
4317 {
4318           snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
4319               "Rfmon mode doesn't apply on a pcap_open_dead pcap_t");
4320           return (PCAP_ERROR);
4321 }
4322 
4323 static int
4324 pcap_read_dead(pcap_t *p, int cnt _U_, pcap_handler callback _U_,
4325     u_char *user _U_)
4326 {
4327           snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
4328               "Packets aren't available from a pcap_open_dead pcap_t");
4329           return (-1);
4330 }
4331 
4332 static void
4333 pcap_breakloop_dead(pcap_t *p _U_)
4334 {
4335           /*
4336            * A "dead" pcap_t is just a placeholder to use in order to
4337            * compile a filter to BPF code or to open a savefile for
4338            * writing.  It doesn't support any operations, including
4339            * capturing or reading packets, so there will never be a
4340            * get-packets loop in progress to break out *of*.
4341            *
4342            * As such, this routine doesn't need to do anything.
4343            */
4344 }
4345 
4346 static int
4347 pcap_inject_dead(pcap_t *p, const void *buf _U_, size_t size _U_)
4348 {
4349           snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
4350               "Packets can't be sent on a pcap_open_dead pcap_t");
4351           return (-1);
4352 }
4353 
4354 static int
4355 pcap_setfilter_dead(pcap_t *p, struct bpf_program *fp _U_)
4356 {
4357           snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
4358               "A filter cannot be set on a pcap_open_dead pcap_t");
4359           return (-1);
4360 }
4361 
4362 static int
4363 pcap_setdirection_dead(pcap_t *p, pcap_direction_t d _U_)
4364 {
4365           snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
4366               "The packet direction cannot be set on a pcap_open_dead pcap_t");
4367           return (-1);
4368 }
4369 
4370 static int
4371 pcap_set_datalink_dead(pcap_t *p, int dlt _U_)
4372 {
4373           snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
4374               "The link-layer header type cannot be set on a pcap_open_dead pcap_t");
4375           return (-1);
4376 }
4377 
4378 static int
4379 pcap_getnonblock_dead(pcap_t *p)
4380 {
4381           snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
4382               "A pcap_open_dead pcap_t does not have a non-blocking mode setting");
4383           return (-1);
4384 }
4385 
4386 static int
4387 pcap_setnonblock_dead(pcap_t *p, int nonblock _U_)
4388 {
4389           snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
4390               "A pcap_open_dead pcap_t does not have a non-blocking mode setting");
4391           return (-1);
4392 }
4393 
4394 static int
4395 pcap_stats_dead(pcap_t *p, struct pcap_stat *ps _U_)
4396 {
4397           snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
4398               "Statistics aren't available from a pcap_open_dead pcap_t");
4399           return (-1);
4400 }
4401 
4402 #ifdef _WIN32
4403 static struct pcap_stat *
4404 pcap_stats_ex_dead(pcap_t *p, int *pcap_stat_size _U_)
4405 {
4406           snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
4407               "Statistics aren't available from a pcap_open_dead pcap_t");
4408           return (NULL);
4409 }
4410 
4411 static int
4412 pcap_setbuff_dead(pcap_t *p, int dim _U_)
4413 {
4414           snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
4415               "The kernel buffer size cannot be set on a pcap_open_dead pcap_t");
4416           return (-1);
4417 }
4418 
4419 static int
4420 pcap_setmode_dead(pcap_t *p, int mode _U_)
4421 {
4422           snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
4423               "impossible to set mode on a pcap_open_dead pcap_t");
4424           return (-1);
4425 }
4426 
4427 static int
4428 pcap_setmintocopy_dead(pcap_t *p, int size _U_)
4429 {
4430           snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
4431               "The mintocopy parameter cannot be set on a pcap_open_dead pcap_t");
4432           return (-1);
4433 }
4434 
4435 static HANDLE
4436 pcap_getevent_dead(pcap_t *p)
4437 {
4438           snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
4439               "A pcap_open_dead pcap_t has no event handle");
4440           return (INVALID_HANDLE_VALUE);
4441 }
4442 
4443 static int
4444 pcap_oid_get_request_dead(pcap_t *p, bpf_u_int32 oid _U_, void *data _U_,
4445     size_t *lenp _U_)
4446 {
4447           snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
4448               "An OID get request cannot be performed on a pcap_open_dead pcap_t");
4449           return (PCAP_ERROR);
4450 }
4451 
4452 static int
4453 pcap_oid_set_request_dead(pcap_t *p, bpf_u_int32 oid _U_, const void *data _U_,
4454     size_t *lenp _U_)
4455 {
4456           snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
4457               "An OID set request cannot be performed on a pcap_open_dead pcap_t");
4458           return (PCAP_ERROR);
4459 }
4460 
4461 static u_int
4462 pcap_sendqueue_transmit_dead(pcap_t *p, pcap_send_queue *queue _U_,
4463     int sync _U_)
4464 {
4465           snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
4466               "Packets cannot be transmitted on a pcap_open_dead pcap_t");
4467           return (0);
4468 }
4469 
4470 static int
4471 pcap_setuserbuffer_dead(pcap_t *p, int size _U_)
4472 {
4473           snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
4474               "The user buffer cannot be set on a pcap_open_dead pcap_t");
4475           return (-1);
4476 }
4477 
4478 static int
4479 pcap_live_dump_dead(pcap_t *p, char *filename _U_, int maxsize _U_,
4480     int maxpacks _U_)
4481 {
4482           snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
4483               "Live packet dumping cannot be performed on a pcap_open_dead pcap_t");
4484           return (-1);
4485 }
4486 
4487 static int
4488 pcap_live_dump_ended_dead(pcap_t *p, int sync _U_)
4489 {
4490           snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
4491               "Live packet dumping cannot be performed on a pcap_open_dead pcap_t");
4492           return (-1);
4493 }
4494 
4495 static PAirpcapHandle
4496 pcap_get_airpcap_handle_dead(pcap_t *p _U_)
4497 {
4498           return (NULL);
4499 }
4500 #endif /* _WIN32 */
4501 
4502 static void
4503 pcap_cleanup_dead(pcap_t *p _U_)
4504 {
4505           /* Nothing to do. */
4506 }
4507 
4508 pcap_t *
4509 pcap_open_dead_with_tstamp_precision(int linktype, int snaplen, u_int precision)
4510 {
4511           pcap_t *p;
4512 
4513           switch (precision) {
4514 
4515           case PCAP_TSTAMP_PRECISION_MICRO:
4516           case PCAP_TSTAMP_PRECISION_NANO:
4517                     break;
4518 
4519           default:
4520                     /*
4521                      * This doesn't really matter, but we don't have any way
4522                      * to report particular errors, so the only failure we
4523                      * should have is a memory allocation failure.  Just
4524                      * pick microsecond precision.
4525                      */
4526                     precision = PCAP_TSTAMP_PRECISION_MICRO;
4527                     break;
4528           }
4529           p = malloc(sizeof(*p));
4530           if (p == NULL)
4531                     return NULL;
4532           memset (p, 0, sizeof(*p));
4533           p->snapshot = snaplen;
4534           p->linktype = linktype;
4535           p->opt.tstamp_precision = precision;
4536           p->can_set_rfmon_op = pcap_can_set_rfmon_dead;
4537           p->read_op = pcap_read_dead;
4538           p->inject_op = pcap_inject_dead;
4539           p->setfilter_op = pcap_setfilter_dead;
4540           p->setdirection_op = pcap_setdirection_dead;
4541           p->set_datalink_op = pcap_set_datalink_dead;
4542           p->getnonblock_op = pcap_getnonblock_dead;
4543           p->setnonblock_op = pcap_setnonblock_dead;
4544           p->stats_op = pcap_stats_dead;
4545 #ifdef _WIN32
4546           p->stats_ex_op = pcap_stats_ex_dead;
4547           p->setbuff_op = pcap_setbuff_dead;
4548           p->setmode_op = pcap_setmode_dead;
4549           p->setmintocopy_op = pcap_setmintocopy_dead;
4550           p->getevent_op = pcap_getevent_dead;
4551           p->oid_get_request_op = pcap_oid_get_request_dead;
4552           p->oid_set_request_op = pcap_oid_set_request_dead;
4553           p->sendqueue_transmit_op = pcap_sendqueue_transmit_dead;
4554           p->setuserbuffer_op = pcap_setuserbuffer_dead;
4555           p->live_dump_op = pcap_live_dump_dead;
4556           p->live_dump_ended_op = pcap_live_dump_ended_dead;
4557           p->get_airpcap_handle_op = pcap_get_airpcap_handle_dead;
4558 #endif
4559           p->breakloop_op = pcap_breakloop_dead;
4560           p->cleanup_op = pcap_cleanup_dead;
4561 
4562           /*
4563            * A "dead" pcap_t never requires special BPF code generation.
4564            */
4565           p->bpf_codegen_flags = 0;
4566 
4567           p->activated = 1;
4568           return (p);
4569 }
4570 
4571 pcap_t *
4572 pcap_open_dead(int linktype, int snaplen)
4573 {
4574           return (pcap_open_dead_with_tstamp_precision(linktype, snaplen,
4575               PCAP_TSTAMP_PRECISION_MICRO));
4576 }
4577 
4578 #ifdef YYDEBUG
4579 /*
4580  * Set the internal "debug printout" flag for the filter expression parser.
4581  * The code to print that stuff is present only if YYDEBUG is defined, so
4582  * the flag, and the routine to set it, are defined only if YYDEBUG is
4583  * defined.
4584  *
4585  * This is intended for libpcap developers, not for general use.
4586  * If you want to set these in a program, you'll have to declare this
4587  * routine yourself, with the appropriate DLL import attribute on Windows;
4588  * it's not declared in any header file, and won't be declared in any
4589  * header file provided by libpcap.
4590  */
4591 PCAP_API void pcap_set_parser_debug(int value);
4592 
4593 PCAP_API_DEF void
4594 pcap_set_parser_debug(int value)
4595 {
4596           pcap_debug = value;
4597 }
4598 #endif
4599