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      1 /*
      2  * Copyright (c) 1993, 1994, 1995, 1996, 1997, 1998
      3  *	The Regents of the University of California.  All rights reserved.
      4  *
      5  * Redistribution and use in source and binary forms, with or without
      6  * modification, are permitted provided that the following conditions
      7  * are met:
      8  * 1. Redistributions of source code must retain the above copyright
      9  *    notice, this list of conditions and the following disclaimer.
     10  * 2. Redistributions in binary form must reproduce the above copyright
     11  *    notice, this list of conditions and the following disclaimer in the
     12  *    documentation and/or other materials provided with the distribution.
     13  * 3. All advertising materials mentioning features or use of this software
     14  *    must display the following acknowledgement:
     15  *	This product includes software developed by the Computer Systems
     16  *	Engineering Group at Lawrence Berkeley Laboratory.
     17  * 4. Neither the name of the University nor of the Laboratory may be used
     18  *    to endorse or promote products derived from this software without
     19  *    specific prior written permission.
     20  *
     21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     31  * SUCH DAMAGE.
     32  */
     33 
     34 #ifdef HAVE_CONFIG_H
     35 #include <config.h>
     36 #endif
     37 
     38 #include <pcap-types.h>
     39 #ifndef _WIN32
     40 #include <sys/param.h>
     41 #ifndef MSDOS
     42 #include <sys/file.h>
     43 #endif
     44 #include <sys/ioctl.h>
     45 #include <sys/socket.h>
     46 #ifdef HAVE_SYS_SOCKIO_H
     47 #include <sys/sockio.h>
     48 #endif
     49 
     50 struct mbuf;		/* Squelch compiler warnings on some platforms for */
     51 struct rtentry;		/* declarations in <net/if.h> */
     52 #include <net/if.h>
     53 #include <netinet/in.h>
     54 #endif /* _WIN32 */
     55 
     56 #include <ctype.h>
     57 #include <stdio.h>
     58 #include <stdlib.h>
     59 #include <string.h>
     60 #if !defined(_MSC_VER) && !defined(__BORLANDC__) && !defined(__MINGW32__)
     61 #include <unistd.h>
     62 #endif
     63 #include <fcntl.h>
     64 #include <errno.h>
     65 #ifdef HAVE_LIMITS_H
     66 #include <limits.h>
     67 #else
     68 #define INT_MAX		2147483647
     69 #endif
     70 
     71 #ifdef HAVE_OS_PROTO_H
     72 #include "os-proto.h"
     73 #endif
     74 
     75 #ifdef MSDOS
     76 #include "pcap-dos.h"
     77 #endif
     78 
     79 #include "pcap-int.h"
     80 
     81 #include "optimize.h"
     82 
     83 #ifdef HAVE_DAG_API
     84 #include "pcap-dag.h"
     85 #endif /* HAVE_DAG_API */
     86 
     87 #ifdef HAVE_SEPTEL_API
     88 #include "pcap-septel.h"
     89 #endif /* HAVE_SEPTEL_API */
     90 
     91 #ifdef HAVE_SNF_API
     92 #include "pcap-snf.h"
     93 #endif /* HAVE_SNF_API */
     94 
     95 #ifdef HAVE_TC_API
     96 #include "pcap-tc.h"
     97 #endif /* HAVE_TC_API */
     98 
     99 #ifdef PCAP_SUPPORT_USB
    100 #include "pcap-usb-linux.h"
    101 #endif
    102 
    103 #ifdef PCAP_SUPPORT_BT
    104 #include "pcap-bt-linux.h"
    105 #endif
    106 
    107 #ifdef PCAP_SUPPORT_BT_MONITOR
    108 #include "pcap-bt-monitor-linux.h"
    109 #endif
    110 
    111 #ifdef PCAP_SUPPORT_NETFILTER
    112 #include "pcap-netfilter-linux.h"
    113 #endif
    114 
    115 #ifdef PCAP_SUPPORT_NETMAP
    116 #include "pcap-netmap.h"
    117 #endif
    118 
    119 #ifdef PCAP_SUPPORT_DBUS
    120 #include "pcap-dbus.h"
    121 #endif
    122 
    123 #ifdef PCAP_SUPPORT_RDMASNIFF
    124 #include "pcap-rdmasniff.h"
    125 #endif
    126 
    127 #ifdef _WIN32
    128 /*
    129  * DllMain(), required when built as a Windows DLL.
    130  */
    131 BOOL WINAPI DllMain(
    132   HANDLE hinstDLL,
    133   DWORD dwReason,
    134   LPVOID lpvReserved
    135 )
    136 {
    137 	return (TRUE);
    138 }
    139 
    140 /*
    141  * Start WinSock.
    142  * Exported in case some applications using WinPcap called it,
    143  * even though it wasn't exported.
    144  */
    145 int
    146 wsockinit(void)
    147 {
    148 	WORD wVersionRequested;
    149 	WSADATA wsaData;
    150 	static int err = -1;
    151 	static int done = 0;
    152 
    153 	if (done)
    154 		return (err);
    155 
    156 	wVersionRequested = MAKEWORD( 1, 1);
    157 	err = WSAStartup( wVersionRequested, &wsaData );
    158 	atexit ((void(*)(void))WSACleanup);
    159 	done = 1;
    160 
    161 	if ( err != 0 )
    162 		err = -1;
    163 	return (err);
    164 }
    165 
    166 /*
    167  * This is the exported function; new programs should call this.
    168  */
    169 int
    170 pcap_wsockinit(void)
    171 {
    172        return (wsockinit());
    173 }
    174 #endif /* _WIN32 */
    175 
    176 /*
    177  * String containing the library version.
    178  * Not explicitly exported via a header file - the right API to use
    179  * is pcap_lib_version() - but some programs included it, so we
    180  * provide it.
    181  *
    182  * We declare it here, right before defining it, to squelch any
    183  * warnings we might get from compilers about the lack of a
    184  * declaration.
    185  */
    186 PCAP_API char pcap_version[];
    187 PCAP_API_DEF char pcap_version[] = PACKAGE_VERSION;
    188 
    189 static int
    190 pcap_not_initialized(pcap_t *pcap)
    191 {
    192 	if (pcap->activated) {
    193 		/* A module probably forgot to set the function pointer */
    194 		(void)pcap_snprintf(pcap->errbuf, sizeof(pcap->errbuf),
    195 		    "This operation isn't properly handled by that device");
    196 		return (PCAP_ERROR);
    197 	}
    198 	/* in case the caller doesn't check for PCAP_ERROR_NOT_ACTIVATED */
    199 	(void)pcap_snprintf(pcap->errbuf, sizeof(pcap->errbuf),
    200 	    "This handle hasn't been activated yet");
    201 	/* this means 'not initialized' */
    202 	return (PCAP_ERROR_NOT_ACTIVATED);
    203 }
    204 
    205 #ifdef _WIN32
    206 static void *
    207 pcap_not_initialized_ptr(pcap_t *pcap)
    208 {
    209 	if (pcap->activated) {
    210 		/* A module probably forgot to set the function pointer */
    211 		(void)pcap_snprintf(pcap->errbuf, sizeof(pcap->errbuf),
    212 		    "This operation isn't properly handled by that device");
    213 		return (NULL);
    214 	}
    215 	(void)pcap_snprintf(pcap->errbuf, sizeof(pcap->errbuf),
    216 	    "This handle hasn't been activated yet");
    217 	return (NULL);
    218 }
    219 
    220 static HANDLE
    221 pcap_getevent_not_initialized(pcap_t *pcap)
    222 {
    223 	if (pcap->activated) {
    224 		/* A module probably forgot to set the function pointer */
    225 		(void)pcap_snprintf(pcap->errbuf, sizeof(pcap->errbuf),
    226 		    "This operation isn't properly handled by that device");
    227 		return (INVALID_HANDLE_VALUE);
    228 	}
    229 	(void)pcap_snprintf(pcap->errbuf, sizeof(pcap->errbuf),
    230 	    "This handle hasn't been activated yet");
    231 	return (INVALID_HANDLE_VALUE);
    232 }
    233 
    234 static u_int
    235 pcap_sendqueue_transmit_not_initialized(pcap_t *pcap, pcap_send_queue* queue, int sync)
    236 {
    237 	if (pcap->activated) {
    238 		/* A module probably forgot to set the function pointer */
    239 		(void)pcap_snprintf(pcap->errbuf, sizeof(pcap->errbuf),
    240 		    "This operation isn't properly handled by that device");
    241 		return (0);
    242 	}
    243 	(void)pcap_snprintf(pcap->errbuf, sizeof(pcap->errbuf),
    244 	    "This handle hasn't been activated yet");
    245 	return (0);
    246 }
    247 
    248 static PAirpcapHandle
    249 pcap_get_airpcap_handle_not_initialized(pcap_t *pcap)
    250 {
    251 	if (pcap->activated) {
    252 		/* A module probably forgot to set the function pointer */
    253 		(void)pcap_snprintf(pcap->errbuf, sizeof(pcap->errbuf),
    254 		    "This operation isn't properly handled by that device");
    255 		return (NULL);
    256 	}
    257 	(void)pcap_snprintf(pcap->errbuf, sizeof(pcap->errbuf),
    258 	    "This handle hasn't been activated yet");
    259 	return (NULL);
    260 }
    261 #endif
    262 
    263 /*
    264  * Returns 1 if rfmon mode can be set on the pcap_t, 0 if it can't,
    265  * a PCAP_ERROR value on an error.
    266  */
    267 int
    268 pcap_can_set_rfmon(pcap_t *p)
    269 {
    270 	return (p->can_set_rfmon_op(p));
    271 }
    272 
    273 /*
    274  * For systems where rfmon mode is never supported.
    275  */
    276 static int
    277 pcap_cant_set_rfmon(pcap_t *p _U_)
    278 {
    279 	return (0);
    280 }
    281 
    282 /*
    283  * Sets *tstamp_typesp to point to an array 1 or more supported time stamp
    284  * types; the return value is the number of supported time stamp types.
    285  * The list should be freed by a call to pcap_free_tstamp_types() when
    286  * you're done with it.
    287  *
    288  * A return value of 0 means "you don't get a choice of time stamp type",
    289  * in which case *tstamp_typesp is set to null.
    290  *
    291  * PCAP_ERROR is returned on error.
    292  */
    293 int
    294 pcap_list_tstamp_types(pcap_t *p, int **tstamp_typesp)
    295 {
    296 	if (p->tstamp_type_count == 0) {
    297 		/*
    298 		 * We don't support multiple time stamp types.
    299 		 */
    300 		*tstamp_typesp = NULL;
    301 	} else {
    302 		*tstamp_typesp = (int*)calloc(sizeof(**tstamp_typesp),
    303 		    p->tstamp_type_count);
    304 		if (*tstamp_typesp == NULL) {
    305 			pcap_fmt_errmsg_for_errno(p->errbuf, sizeof(p->errbuf),
    306 			    errno, "malloc");
    307 			return (PCAP_ERROR);
    308 		}
    309 		(void)memcpy(*tstamp_typesp, p->tstamp_type_list,
    310 		    sizeof(**tstamp_typesp) * p->tstamp_type_count);
    311 	}
    312 	return (p->tstamp_type_count);
    313 }
    314 
    315 /*
    316  * In Windows, you might have a library built with one version of the
    317  * C runtime library and an application built with another version of
    318  * the C runtime library, which means that the library might use one
    319  * version of malloc() and free() and the application might use another
    320  * version of malloc() and free().  If so, that means something
    321  * allocated by the library cannot be freed by the application, so we
    322  * need to have a pcap_free_tstamp_types() routine to free up the list
    323  * allocated by pcap_list_tstamp_types(), even though it's just a wrapper
    324  * around free().
    325  */
    326 void
    327 pcap_free_tstamp_types(int *tstamp_type_list)
    328 {
    329 	free(tstamp_type_list);
    330 }
    331 
    332 /*
    333  * Default one-shot callback; overridden for capture types where the
    334  * packet data cannot be guaranteed to be available after the callback
    335  * returns, so that a copy must be made.
    336  */
    337 void
    338 pcap_oneshot(u_char *user, const struct pcap_pkthdr *h, const u_char *pkt)
    339 {
    340 	struct oneshot_userdata *sp = (struct oneshot_userdata *)user;
    341 
    342 	*sp->hdr = *h;
    343 	*sp->pkt = pkt;
    344 }
    345 
    346 const u_char *
    347 pcap_next(pcap_t *p, struct pcap_pkthdr *h)
    348 {
    349 	struct oneshot_userdata s;
    350 	const u_char *pkt;
    351 
    352 	s.hdr = h;
    353 	s.pkt = &pkt;
    354 	s.pd = p;
    355 	if (pcap_dispatch(p, 1, p->oneshot_callback, (u_char *)&s) <= 0)
    356 		return (0);
    357 	return (pkt);
    358 }
    359 
    360 int
    361 pcap_next_ex(pcap_t *p, struct pcap_pkthdr **pkt_header,
    362     const u_char **pkt_data)
    363 {
    364 	struct oneshot_userdata s;
    365 
    366 	s.hdr = &p->pcap_header;
    367 	s.pkt = pkt_data;
    368 	s.pd = p;
    369 
    370 	/* Saves a pointer to the packet headers */
    371 	*pkt_header= &p->pcap_header;
    372 
    373 	if (p->rfile != NULL) {
    374 		int status;
    375 
    376 		/* We are on an offline capture */
    377 		status = pcap_offline_read(p, 1, p->oneshot_callback,
    378 		    (u_char *)&s);
    379 
    380 		/*
    381 		 * Return codes for pcap_offline_read() are:
    382 		 *   -  0: EOF
    383 		 *   - -1: error
    384 		 *   - >1: OK
    385 		 * The first one ('0') conflicts with the return code of
    386 		 * 0 from pcap_read() meaning "no packets arrived before
    387 		 * the timeout expired", so we map it to -2 so you can
    388 		 * distinguish between an EOF from a savefile and a
    389 		 * "no packets arrived before the timeout expired, try
    390 		 * again" from a live capture.
    391 		 */
    392 		if (status == 0)
    393 			return (-2);
    394 		else
    395 			return (status);
    396 	}
    397 
    398 	/*
    399 	 * Return codes for pcap_read() are:
    400 	 *   -  0: timeout
    401 	 *   - -1: error
    402 	 *   - -2: loop was broken out of with pcap_breakloop()
    403 	 *   - >1: OK
    404 	 * The first one ('0') conflicts with the return code of 0 from
    405 	 * pcap_offline_read() meaning "end of file".
    406 	*/
    407 	return (p->read_op(p, 1, p->oneshot_callback, (u_char *)&s));
    408 }
    409 
    410 /*
    411  * Implementation of a pcap_if_list_t.
    412  */
    413 struct pcap_if_list {
    414 	pcap_if_t *beginning;
    415 };
    416 
    417 static struct capture_source_type {
    418 	int (*findalldevs_op)(pcap_if_list_t *, char *);
    419 	pcap_t *(*create_op)(const char *, char *, int *);
    420 } capture_source_types[] = {
    421 #ifdef HAVE_DAG_API
    422 	{ dag_findalldevs, dag_create },
    423 #endif
    424 #ifdef HAVE_SEPTEL_API
    425 	{ septel_findalldevs, septel_create },
    426 #endif
    427 #ifdef HAVE_SNF_API
    428 	{ snf_findalldevs, snf_create },
    429 #endif
    430 #ifdef HAVE_TC_API
    431 	{ TcFindAllDevs, TcCreate },
    432 #endif
    433 #ifdef PCAP_SUPPORT_BT
    434 	{ bt_findalldevs, bt_create },
    435 #endif
    436 #ifdef PCAP_SUPPORT_BT_MONITOR
    437 	{ bt_monitor_findalldevs, bt_monitor_create },
    438 #endif
    439 #ifdef PCAP_SUPPORT_USB
    440 	{ usb_findalldevs, usb_create },
    441 #endif
    442 #ifdef PCAP_SUPPORT_NETFILTER
    443 	{ netfilter_findalldevs, netfilter_create },
    444 #endif
    445 #ifdef PCAP_SUPPORT_NETMAP
    446 	{ pcap_netmap_findalldevs, pcap_netmap_create },
    447 #endif
    448 #ifdef PCAP_SUPPORT_DBUS
    449 	{ dbus_findalldevs, dbus_create },
    450 #endif
    451 #ifdef PCAP_SUPPORT_RDMASNIFF
    452 	{ rdmasniff_findalldevs, rdmasniff_create },
    453 #endif
    454 	{ NULL, NULL }
    455 };
    456 
    457 /*
    458  * Get a list of all capture sources that are up and that we can open.
    459  * Returns -1 on error, 0 otherwise.
    460  * The list, as returned through "alldevsp", may be null if no interfaces
    461  * were up and could be opened.
    462  */
    463 int
    464 pcap_findalldevs(pcap_if_t **alldevsp, char *errbuf)
    465 {
    466 	size_t i;
    467 	pcap_if_list_t devlist;
    468 
    469 	/*
    470 	 * Find all the local network interfaces on which we
    471 	 * can capture.
    472 	 */
    473 	devlist.beginning = NULL;
    474 	if (pcap_platform_finddevs(&devlist, errbuf) == -1) {
    475 		/*
    476 		 * Failed - free all of the entries we were given
    477 		 * before we failed.
    478 		 */
    479 		if (devlist.beginning != NULL)
    480 			pcap_freealldevs(devlist.beginning);
    481 		*alldevsp = NULL;
    482 		return (-1);
    483 	}
    484 
    485 	/*
    486 	 * Ask each of the non-local-network-interface capture
    487 	 * source types what interfaces they have.
    488 	 */
    489 	for (i = 0; capture_source_types[i].findalldevs_op != NULL; i++) {
    490 		if (capture_source_types[i].findalldevs_op(&devlist, errbuf) == -1) {
    491 			/*
    492 			 * We had an error; free the list we've been
    493 			 * constructing.
    494 			 */
    495 			if (devlist.beginning != NULL)
    496 				pcap_freealldevs(devlist.beginning);
    497 			*alldevsp = NULL;
    498 			return (-1);
    499 		}
    500 	}
    501 
    502 	/*
    503 	 * Return the first entry of the list of all devices.
    504 	 */
    505 	*alldevsp = devlist.beginning;
    506 	return (0);
    507 }
    508 
    509 static struct sockaddr *
    510 dup_sockaddr(struct sockaddr *sa, size_t sa_length)
    511 {
    512 	struct sockaddr *newsa;
    513 
    514 	if ((newsa = malloc(sa_length)) == NULL)
    515 		return (NULL);
    516 	return (memcpy(newsa, sa, sa_length));
    517 }
    518 
    519 /*
    520  * Construct a "figure of merit" for an interface, for use when sorting
    521  * the list of interfaces, in which interfaces that are up are superior
    522  * to interfaces that aren't up, interfaces that are up and running are
    523  * superior to interfaces that are up but not running, and non-loopback
    524  * interfaces that are up and running are superior to loopback interfaces,
    525  * and interfaces with the same flags have a figure of merit that's higher
    526  * the lower the instance number.
    527  *
    528  * The goal is to try to put the interfaces most likely to be useful for
    529  * capture at the beginning of the list.
    530  *
    531  * The figure of merit, which is lower the "better" the interface is,
    532  * has the uppermost bit set if the interface isn't running, the bit
    533  * below that set if the interface isn't up, the bit below that set
    534  * if the interface is a loopback interface, and the interface index
    535  * in the 29 bits below that.  (Yes, we assume u_int is 32 bits.)
    536  */
    537 static u_int
    538 get_figure_of_merit(pcap_if_t *dev)
    539 {
    540 	const char *cp;
    541 	u_int n;
    542 
    543 	if (strcmp(dev->name, "any") == 0) {
    544 		/*
    545 		 * Give the "any" device an artificially high instance
    546 		 * number, so it shows up after all other non-loopback
    547 		 * interfaces.
    548 		 */
    549 		n = 0x1FFFFFFF;	/* 29 all-1 bits */
    550 	} else {
    551 		/*
    552 		 * A number at the end of the device name string is
    553 		 * assumed to be an instance number.  Add 1 to the
    554 		 * instance number, and use 0 for "no instance
    555 		 * number", so we don't put "no instance number"
    556 		 * devices and "instance 0" devices together.
    557 		 */
    558 		cp = dev->name + strlen(dev->name) - 1;
    559 		while (cp-1 >= dev->name && *(cp-1) >= '0' && *(cp-1) <= '9')
    560 			cp--;
    561 		if (*cp >= '0' && *cp <= '9')
    562 			n = atoi(cp) + 1;
    563 		else
    564 			n = 0;
    565 	}
    566 	if (!(dev->flags & PCAP_IF_RUNNING))
    567 		n |= 0x80000000;
    568 	if (!(dev->flags & PCAP_IF_UP))
    569 		n |= 0x40000000;
    570 
    571 	/*
    572 	 * Give non-wireless interfaces that aren't disconnected a better
    573 	 * figure of merit than interfaces that are disconnected, as
    574 	 * "disconnected" should indicate that the interface isn't
    575 	 * plugged into a network and thus won't give you any traffic.
    576 	 *
    577 	 * For wireless interfaces, it means "associated with a network",
    578 	 * which we presume not to necessarily prevent capture, as you
    579 	 * might run the adapter in some flavor of monitor mode.
    580 	 */
    581 	if (!(dev->flags & PCAP_IF_WIRELESS) &&
    582 	    (dev->flags & PCAP_IF_CONNECTION_STATUS) == PCAP_IF_CONNECTION_STATUS_DISCONNECTED)
    583 		n |= 0x20000000;
    584 
    585 	/*
    586 	 * Sort loopback devices after non-loopback devices, *except* for
    587 	 * disconnected devices.
    588 	 */
    589 	if (dev->flags & PCAP_IF_LOOPBACK)
    590 		n |= 0x10000000;
    591 
    592 	return (n);
    593 }
    594 
    595 #ifndef _WIN32
    596 /*
    597  * Try to get a description for a given device.
    598  * Returns a mallocated description if it could and NULL if it couldn't.
    599  *
    600  * XXX - on FreeBSDs that support it, should it get the sysctl named
    601  * "dev.{adapter family name}.{adapter unit}.%desc" to get a description
    602  * of the adapter?  Note that "dev.an.0.%desc" is "Aironet PC4500/PC4800"
    603  * with my Cisco 350 card, so the name isn't entirely descriptive.  The
    604  * "dev.an.0.%pnpinfo" has a better description, although one might argue
    605  * that the problem is really a driver bug - if it can find out that it's
    606  * a Cisco 340 or 350, rather than an old Aironet card, it should use
    607  * that in the description.
    608  *
    609  * Do NetBSD, DragonflyBSD, or OpenBSD support this as well?  FreeBSD
    610  * and OpenBSD let you get a description, but it's not generated by the OS,
    611  * it's set with another ioctl that ifconfig supports; we use that to get
    612  * a description in FreeBSD and OpenBSD, but if there is no such
    613  * description available, it still might be nice to get some description
    614  * string based on the device type or something such as that.
    615  *
    616  * In macOS, the System Configuration framework can apparently return
    617  * names in 10.4 and later.
    618  *
    619  * It also appears that freedesktop.org's HAL offers an "info.product"
    620  * string, but the HAL specification says it "should not be used in any
    621  * UI" and "subsystem/capability specific properties" should be used
    622  * instead and, in any case, I think HAL is being deprecated in
    623  * favor of other stuff such as DeviceKit.  DeviceKit doesn't appear
    624  * to have any obvious product information for devices, but maybe
    625  * I haven't looked hard enough.
    626  *
    627  * Using the System Configuration framework, or HAL, or DeviceKit, or
    628  * whatever, would require that libpcap applications be linked with
    629  * the frameworks/libraries in question.  That shouldn't be a problem
    630  * for programs linking with the shared version of libpcap (unless
    631  * you're running on AIX - which I think is the only UN*X that doesn't
    632  * support linking a shared library with other libraries on which it
    633  * depends, and having an executable linked only with the first shared
    634  * library automatically pick up the other libraries when started -
    635  * and using HAL or whatever).  Programs linked with the static
    636  * version of libpcap would have to use pcap-config with the --static
    637  * flag in order to get the right linker flags in order to pick up
    638  * the additional libraries/frameworks; those programs need that anyway
    639  * for libpcap 1.1 and beyond on Linux, as, by default, it requires
    640  * -lnl.
    641  *
    642  * Do any other UN*Xes, or desktop environments support getting a
    643  * description?
    644  */
    645 static char *
    646 #ifdef SIOCGIFDESCR
    647 get_if_description(const char *name)
    648 {
    649 	char *description = NULL;
    650 	int s;
    651 	struct ifreq ifrdesc;
    652 #ifndef IFDESCRSIZE
    653 	size_t descrlen = 64;
    654 #else
    655 	size_t descrlen = IFDESCRSIZE;
    656 #endif /* IFDESCRSIZE */
    657 
    658 	/*
    659 	 * Get the description for the interface.
    660 	 */
    661 	memset(&ifrdesc, 0, sizeof ifrdesc);
    662 	strlcpy(ifrdesc.ifr_name, name, sizeof ifrdesc.ifr_name);
    663 	s = socket(AF_INET, SOCK_DGRAM, 0);
    664 	if (s >= 0) {
    665 #ifdef __FreeBSD__
    666 		/*
    667 		 * On FreeBSD, if the buffer isn't big enough for the
    668 		 * description, the ioctl succeeds, but the description
    669 		 * isn't copied, ifr_buffer.length is set to the description
    670 		 * length, and ifr_buffer.buffer is set to NULL.
    671 		 */
    672 		for (;;) {
    673 			free(description);
    674 			if ((description = malloc(descrlen)) != NULL) {
    675 				ifrdesc.ifr_buffer.buffer = description;
    676 				ifrdesc.ifr_buffer.length = descrlen;
    677 				if (ioctl(s, SIOCGIFDESCR, &ifrdesc) == 0) {
    678 					if (ifrdesc.ifr_buffer.buffer ==
    679 					    description)
    680 						break;
    681 					else
    682 						descrlen = ifrdesc.ifr_buffer.length;
    683 				} else {
    684 					/*
    685 					 * Failed to get interface description.
    686 					 */
    687 					free(description);
    688 					description = NULL;
    689 					break;
    690 				}
    691 			} else
    692 				break;
    693 		}
    694 #else /* __FreeBSD__ */
    695 		/*
    696 		 * The only other OS that currently supports
    697 		 * SIOCGIFDESCR is OpenBSD, and it has no way
    698 		 * to get the description length - it's clamped
    699 		 * to a maximum of IFDESCRSIZE.
    700 		 */
    701 		if ((description = malloc(descrlen)) != NULL) {
    702 			ifrdesc.ifr_data = (caddr_t)description;
    703 			if (ioctl(s, SIOCGIFDESCR, &ifrdesc) != 0) {
    704 				/*
    705 				 * Failed to get interface description.
    706 				 */
    707 				free(description);
    708 				description = NULL;
    709 			}
    710 		}
    711 #endif /* __FreeBSD__ */
    712 		close(s);
    713 		if (description != NULL && strlen(description) == 0) {
    714 			/*
    715 			 * Description is empty, so discard it.
    716 			 */
    717 			free(description);
    718 			description = NULL;
    719 		}
    720 	}
    721 
    722 #ifdef __FreeBSD__
    723 	/*
    724 	 * For FreeBSD, if we didn't get a description, and this is
    725 	 * a device with a name of the form usbusN, label it as a USB
    726 	 * bus.
    727 	 */
    728 	if (description == NULL) {
    729 		if (strncmp(name, "usbus", 5) == 0) {
    730 			/*
    731 			 * OK, it begins with "usbus".
    732 			 */
    733 			long busnum;
    734 			char *p;
    735 
    736 			errno = 0;
    737 			busnum = strtol(name + 5, &p, 10);
    738 			if (errno == 0 && p != name + 5 && *p == '\0' &&
    739 			    busnum >= 0 && busnum <= INT_MAX) {
    740 				/*
    741 				 * OK, it's a valid number that's not
    742 				 * bigger than INT_MAX.  Construct
    743 				 * a description from it.
    744 				 */
    745 				static const char descr_prefix[] = "USB bus number ";
    746 				size_t descr_size;
    747 
    748 				/*
    749 				 * Allow enough room for a 32-bit bus number.
    750 				 * sizeof (descr_prefix) includes the
    751 				 * terminating NUL.
    752 				 */
    753 				descr_size = sizeof (descr_prefix) + 10;
    754 				description = malloc(descr_size);
    755 				if (description != NULL) {
    756 					pcap_snprintf(description, descr_size,
    757 					    "%s%ld", descr_prefix, busnum);
    758 				}
    759 			}
    760 		}
    761 	}
    762 #endif
    763 	return (description);
    764 #else /* SIOCGIFDESCR */
    765 get_if_description(const char *name _U_)
    766 {
    767 	return (NULL);
    768 #endif /* SIOCGIFDESCR */
    769 }
    770 
    771 /*
    772  * Look for a given device in the specified list of devices.
    773  *
    774  * If we find it, return a pointer to its entry.
    775  *
    776  * If we don't find it, attempt to add an entry for it, with the specified
    777  * IFF_ flags and description, and, if that succeeds, return a pointer to
    778  * the new entry, otherwise return NULL and set errbuf to an error message.
    779  */
    780 pcap_if_t *
    781 find_or_add_if(pcap_if_list_t *devlistp, const char *name,
    782     bpf_u_int32 if_flags, get_if_flags_func get_flags_func, char *errbuf)
    783 {
    784 	bpf_u_int32 pcap_flags;
    785 
    786 	/*
    787 	 * Convert IFF_ flags to pcap flags.
    788 	 */
    789 	pcap_flags = 0;
    790 #ifdef IFF_LOOPBACK
    791 	if (if_flags & IFF_LOOPBACK)
    792 		pcap_flags |= PCAP_IF_LOOPBACK;
    793 #else
    794 	/*
    795 	 * We don't have IFF_LOOPBACK, so look at the device name to
    796 	 * see if it looks like a loopback device.
    797 	 */
    798 	if (name[0] == 'l' && name[1] == 'o' &&
    799 	    (isdigit((unsigned char)(name[2])) || name[2] == '\0')
    800 		pcap_flags |= PCAP_IF_LOOPBACK;
    801 #endif
    802 #ifdef IFF_UP
    803 	if (if_flags & IFF_UP)
    804 		pcap_flags |= PCAP_IF_UP;
    805 #endif
    806 #ifdef IFF_RUNNING
    807 	if (if_flags & IFF_RUNNING)
    808 		pcap_flags |= PCAP_IF_RUNNING;
    809 #endif
    810 
    811 	/*
    812 	 * Attempt to find an entry for this device; if we don't find one,
    813 	 * attempt to add one.
    814 	 */
    815 	return (find_or_add_dev(devlistp, name, pcap_flags,
    816 	    get_flags_func, get_if_description(name), errbuf));
    817 }
    818 
    819 /*
    820  * Look for a given device in the specified list of devices.
    821  *
    822  * If we find it, then, if the specified address isn't null, add it to
    823  * the list of addresses for the device and return 0.
    824  *
    825  * If we don't find it, attempt to add an entry for it, with the specified
    826  * IFF_ flags and description, and, if that succeeds, add the specified
    827  * address to its list of addresses if that address is non-null, and
    828  * return 0, otherwise return -1 and set errbuf to an error message.
    829  *
    830  * (We can get called with a null address because we might get a list
    831  * of interface name/address combinations from the underlying OS, with
    832  * the address being absent in some cases, rather than a list of
    833  * interfaces with each interface having a list of addresses, so this
    834  * call may be the only call made to add to the list, and we want to
    835  * add interfaces even if they have no addresses.)
    836  */
    837 int
    838 add_addr_to_if(pcap_if_list_t *devlistp, const char *name,
    839     bpf_u_int32 if_flags, get_if_flags_func get_flags_func,
    840     struct sockaddr *addr, size_t addr_size,
    841     struct sockaddr *netmask, size_t netmask_size,
    842     struct sockaddr *broadaddr, size_t broadaddr_size,
    843     struct sockaddr *dstaddr, size_t dstaddr_size,
    844     char *errbuf)
    845 {
    846 	pcap_if_t *curdev;
    847 
    848 	/*
    849 	 * Check whether the device exists and, if not, add it.
    850 	 */
    851 	curdev = find_or_add_if(devlistp, name, if_flags, get_flags_func,
    852 	    errbuf);
    853 	if (curdev == NULL) {
    854 		/*
    855 		 * Error - give up.
    856 		 */
    857 		return (-1);
    858 	}
    859 
    860 	if (addr == NULL) {
    861 		/*
    862 		 * There's no address to add; this entry just meant
    863 		 * "here's a new interface".
    864 		 */
    865 		return (0);
    866 	}
    867 
    868 	/*
    869 	 * "curdev" is an entry for this interface, and we have an
    870 	 * address for it; add an entry for that address to the
    871 	 * interface's list of addresses.
    872 	 */
    873 	return (add_addr_to_dev(curdev, addr, addr_size, netmask,
    874 	    netmask_size, broadaddr, broadaddr_size, dstaddr,
    875 	    dstaddr_size, errbuf));
    876 }
    877 #endif /* _WIN32 */
    878 
    879 /*
    880  * Add an entry to the list of addresses for an interface.
    881  * "curdev" is the entry for that interface.
    882  */
    883 int
    884 add_addr_to_dev(pcap_if_t *curdev,
    885     struct sockaddr *addr, size_t addr_size,
    886     struct sockaddr *netmask, size_t netmask_size,
    887     struct sockaddr *broadaddr, size_t broadaddr_size,
    888     struct sockaddr *dstaddr, size_t dstaddr_size,
    889     char *errbuf)
    890 {
    891 	pcap_addr_t *curaddr, *prevaddr, *nextaddr;
    892 
    893 	/*
    894 	 * Allocate the new entry and fill it in.
    895 	 */
    896 	curaddr = (pcap_addr_t *)malloc(sizeof(pcap_addr_t));
    897 	if (curaddr == NULL) {
    898 		pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
    899 		    errno, "malloc");
    900 		return (-1);
    901 	}
    902 
    903 	curaddr->next = NULL;
    904 	if (addr != NULL && addr_size != 0) {
    905 		curaddr->addr = (struct sockaddr *)dup_sockaddr(addr, addr_size);
    906 		if (curaddr->addr == NULL) {
    907 			pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
    908 			    errno, "malloc");
    909 			free(curaddr);
    910 			return (-1);
    911 		}
    912 	} else
    913 		curaddr->addr = NULL;
    914 
    915 	if (netmask != NULL && netmask_size != 0) {
    916 		curaddr->netmask = (struct sockaddr *)dup_sockaddr(netmask, netmask_size);
    917 		if (curaddr->netmask == NULL) {
    918 			pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
    919 			    errno, "malloc");
    920 			if (curaddr->addr != NULL)
    921 				free(curaddr->addr);
    922 			free(curaddr);
    923 			return (-1);
    924 		}
    925 	} else
    926 		curaddr->netmask = NULL;
    927 
    928 	if (broadaddr != NULL && broadaddr_size != 0) {
    929 		curaddr->broadaddr = (struct sockaddr *)dup_sockaddr(broadaddr, broadaddr_size);
    930 		if (curaddr->broadaddr == NULL) {
    931 			pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
    932 			    errno, "malloc");
    933 			if (curaddr->netmask != NULL)
    934 				free(curaddr->netmask);
    935 			if (curaddr->addr != NULL)
    936 				free(curaddr->addr);
    937 			free(curaddr);
    938 			return (-1);
    939 		}
    940 	} else
    941 		curaddr->broadaddr = NULL;
    942 
    943 	if (dstaddr != NULL && dstaddr_size != 0) {
    944 		curaddr->dstaddr = (struct sockaddr *)dup_sockaddr(dstaddr, dstaddr_size);
    945 		if (curaddr->dstaddr == NULL) {
    946 			pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
    947 			    errno, "malloc");
    948 			if (curaddr->broadaddr != NULL)
    949 				free(curaddr->broadaddr);
    950 			if (curaddr->netmask != NULL)
    951 				free(curaddr->netmask);
    952 			if (curaddr->addr != NULL)
    953 				free(curaddr->addr);
    954 			free(curaddr);
    955 			return (-1);
    956 		}
    957 	} else
    958 		curaddr->dstaddr = NULL;
    959 
    960 	/*
    961 	 * Find the end of the list of addresses.
    962 	 */
    963 	for (prevaddr = curdev->addresses; prevaddr != NULL; prevaddr = nextaddr) {
    964 		nextaddr = prevaddr->next;
    965 		if (nextaddr == NULL) {
    966 			/*
    967 			 * This is the end of the list.
    968 			 */
    969 			break;
    970 		}
    971 	}
    972 
    973 	if (prevaddr == NULL) {
    974 		/*
    975 		 * The list was empty; this is the first member.
    976 		 */
    977 		curdev->addresses = curaddr;
    978 	} else {
    979 		/*
    980 		 * "prevaddr" is the last member of the list; append
    981 		 * this member to it.
    982 		 */
    983 		prevaddr->next = curaddr;
    984 	}
    985 
    986 	return (0);
    987 }
    988 
    989 /*
    990  * Look for a given device in the specified list of devices.
    991  *
    992  * If we find it, return 0 and set *curdev_ret to point to it.
    993  *
    994  * If we don't find it, attempt to add an entry for it, with the specified
    995  * flags and description, and, if that succeeds, return 0, otherwise
    996  * return -1 and set errbuf to an error message.
    997  */
    998 pcap_if_t *
    999 find_or_add_dev(pcap_if_list_t *devlistp, const char *name, bpf_u_int32 flags,
   1000     get_if_flags_func get_flags_func, const char *description, char *errbuf)
   1001 {
   1002 	pcap_if_t *curdev;
   1003 
   1004 	/*
   1005 	 * Is there already an entry in the list for this device?
   1006 	 */
   1007 	curdev = find_dev(devlistp, name);
   1008 	if (curdev != NULL) {
   1009 		/*
   1010 		 * Yes, return it.
   1011 		 */
   1012 		return (curdev);
   1013 	}
   1014 
   1015 	/*
   1016 	 * No, we didn't find it.
   1017 	 */
   1018 
   1019 	/*
   1020 	 * Try to get additional flags for the device.
   1021 	 */
   1022 	if ((*get_flags_func)(name, &flags, errbuf) == -1) {
   1023 		/*
   1024 		 * Failed.
   1025 		 */
   1026 		return (NULL);
   1027 	}
   1028 
   1029 	/*
   1030 	 * Now, try to add it to the list of devices.
   1031 	 */
   1032 	return (add_dev(devlistp, name, flags, description, errbuf));
   1033 }
   1034 
   1035 /*
   1036  * Look for a given device in the specified list of devices, and return
   1037  * the entry for it if we find it or NULL if we don't.
   1038  */
   1039 pcap_if_t *
   1040 find_dev(pcap_if_list_t *devlistp, const char *name)
   1041 {
   1042 	pcap_if_t *curdev;
   1043 
   1044 	/*
   1045 	 * Is there an entry in the list for this device?
   1046 	 */
   1047 	for (curdev = devlistp->beginning; curdev != NULL;
   1048 	    curdev = curdev->next) {
   1049 		if (strcmp(name, curdev->name) == 0) {
   1050 			/*
   1051 			 * We found it, so, yes, there is.  No need to
   1052 			 * add it.  Provide the entry we found to our
   1053 			 * caller.
   1054 			 */
   1055 			return (curdev);
   1056 		}
   1057 	}
   1058 
   1059 	/*
   1060 	 * No.
   1061 	 */
   1062 	return (NULL);
   1063 }
   1064 
   1065 /*
   1066  * Attempt to add an entry for a device, with the specified flags
   1067  * and description, and, if that succeeds, return 0 and return a pointer
   1068  * to the new entry, otherwise return NULL and set errbuf to an error
   1069  * message.
   1070  *
   1071  * If we weren't given a description, try to get one.
   1072  */
   1073 pcap_if_t *
   1074 add_dev(pcap_if_list_t *devlistp, const char *name, bpf_u_int32 flags,
   1075     const char *description, char *errbuf)
   1076 {
   1077 	pcap_if_t *curdev, *prevdev, *nextdev;
   1078 	u_int this_figure_of_merit, nextdev_figure_of_merit;
   1079 
   1080 	curdev = malloc(sizeof(pcap_if_t));
   1081 	if (curdev == NULL) {
   1082 		pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
   1083 		    errno, "malloc");
   1084 		return (NULL);
   1085 	}
   1086 
   1087 	/*
   1088 	 * Fill in the entry.
   1089 	 */
   1090 	curdev->next = NULL;
   1091 	curdev->name = strdup(name);
   1092 	if (curdev->name == NULL) {
   1093 		pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
   1094 		    errno, "malloc");
   1095 		free(curdev);
   1096 		return (NULL);
   1097 	}
   1098 	if (description == NULL) {
   1099 		/*
   1100 		 * We weren't handed a description for the interface.
   1101 		 */
   1102 		curdev->description = NULL;
   1103 	} else {
   1104 		/*
   1105 		 * We were handed a description; make a copy.
   1106 		 */
   1107 		curdev->description = strdup(description);
   1108 		if (curdev->description == NULL) {
   1109 			pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
   1110 			    errno, "malloc");
   1111 			free(curdev->name);
   1112 			free(curdev);
   1113 			return (NULL);
   1114 		}
   1115 	}
   1116 	curdev->addresses = NULL;	/* list starts out as empty */
   1117 	curdev->flags = flags;
   1118 
   1119 	/*
   1120 	 * Add it to the list, in the appropriate location.
   1121 	 * First, get the "figure of merit" for this interface.
   1122 	 */
   1123 	this_figure_of_merit = get_figure_of_merit(curdev);
   1124 
   1125 	/*
   1126 	 * Now look for the last interface with an figure of merit
   1127 	 * less than or equal to the new interface's figure of merit.
   1128 	 *
   1129 	 * We start with "prevdev" being NULL, meaning we're before
   1130 	 * the first element in the list.
   1131 	 */
   1132 	prevdev = NULL;
   1133 	for (;;) {
   1134 		/*
   1135 		 * Get the interface after this one.
   1136 		 */
   1137 		if (prevdev == NULL) {
   1138 			/*
   1139 			 * The next element is the first element.
   1140 			 */
   1141 			nextdev = devlistp->beginning;
   1142 		} else
   1143 			nextdev = prevdev->next;
   1144 
   1145 		/*
   1146 		 * Are we at the end of the list?
   1147 		 */
   1148 		if (nextdev == NULL) {
   1149 			/*
   1150 			 * Yes - we have to put the new entry after "prevdev".
   1151 			 */
   1152 			break;
   1153 		}
   1154 
   1155 		/*
   1156 		 * Is the new interface's figure of merit less
   1157 		 * than the next interface's figure of merit,
   1158 		 * meaning that the new interface is better
   1159 		 * than the next interface?
   1160 		 */
   1161 		nextdev_figure_of_merit = get_figure_of_merit(nextdev);
   1162 		if (this_figure_of_merit < nextdev_figure_of_merit) {
   1163 			/*
   1164 			 * Yes - we should put the new entry
   1165 			 * before "nextdev", i.e. after "prevdev".
   1166 			 */
   1167 			break;
   1168 		}
   1169 
   1170 		prevdev = nextdev;
   1171 	}
   1172 
   1173 	/*
   1174 	 * Insert before "nextdev".
   1175 	 */
   1176 	curdev->next = nextdev;
   1177 
   1178 	/*
   1179 	 * Insert after "prevdev" - unless "prevdev" is null,
   1180 	 * in which case this is the first interface.
   1181 	 */
   1182 	if (prevdev == NULL) {
   1183 		/*
   1184 		 * This is the first interface.  Make it
   1185 		 * the first element in the list of devices.
   1186 		 */
   1187 		devlistp->beginning = curdev;
   1188 	} else
   1189 		prevdev->next = curdev;
   1190 	return (curdev);
   1191 }
   1192 
   1193 /*
   1194  * Free a list of interfaces.
   1195  */
   1196 void
   1197 pcap_freealldevs(pcap_if_t *alldevs)
   1198 {
   1199 	pcap_if_t *curdev, *nextdev;
   1200 	pcap_addr_t *curaddr, *nextaddr;
   1201 
   1202 	for (curdev = alldevs; curdev != NULL; curdev = nextdev) {
   1203 		nextdev = curdev->next;
   1204 
   1205 		/*
   1206 		 * Free all addresses.
   1207 		 */
   1208 		for (curaddr = curdev->addresses; curaddr != NULL; curaddr = nextaddr) {
   1209 			nextaddr = curaddr->next;
   1210 			if (curaddr->addr)
   1211 				free(curaddr->addr);
   1212 			if (curaddr->netmask)
   1213 				free(curaddr->netmask);
   1214 			if (curaddr->broadaddr)
   1215 				free(curaddr->broadaddr);
   1216 			if (curaddr->dstaddr)
   1217 				free(curaddr->dstaddr);
   1218 			free(curaddr);
   1219 		}
   1220 
   1221 		/*
   1222 		 * Free the name string.
   1223 		 */
   1224 		free(curdev->name);
   1225 
   1226 		/*
   1227 		 * Free the description string, if any.
   1228 		 */
   1229 		if (curdev->description != NULL)
   1230 			free(curdev->description);
   1231 
   1232 		/*
   1233 		 * Free the interface.
   1234 		 */
   1235 		free(curdev);
   1236 	}
   1237 }
   1238 
   1239 /*
   1240  * pcap-npf.c has its own pcap_lookupdev(), for compatibility reasons, as
   1241  * it actually returns the names of all interfaces, with a NUL separator
   1242  * between them; some callers may depend on that.
   1243  *
   1244  * MS-DOS has its own pcap_lookupdev(), but that might be useful only
   1245  * as an optimization.
   1246  *
   1247  * In all other cases, we just use pcap_findalldevs() to get a list of
   1248  * devices, and pick from that list.
   1249  */
   1250 #if !defined(HAVE_PACKET32) && !defined(MSDOS)
   1251 /*
   1252  * Return the name of a network interface attached to the system, or NULL
   1253  * if none can be found.  The interface must be configured up; the
   1254  * lowest unit number is preferred; loopback is ignored.
   1255  */
   1256 char *
   1257 pcap_lookupdev(char *errbuf)
   1258 {
   1259 	pcap_if_t *alldevs;
   1260 #ifdef _WIN32
   1261   /*
   1262    * Windows - use the same size as the old WinPcap 3.1 code.
   1263    * XXX - this is probably bigger than it needs to be.
   1264    */
   1265   #define IF_NAMESIZE 8192
   1266 #else
   1267   /*
   1268    * UN*X - use the system's interface name size.
   1269    * XXX - that might not be large enough for capture devices
   1270    * that aren't regular network interfaces.
   1271    */
   1272   /* for old BSD systems, including bsdi3 */
   1273   #ifndef IF_NAMESIZE
   1274   #define IF_NAMESIZE IFNAMSIZ
   1275   #endif
   1276 #endif
   1277 	static char device[IF_NAMESIZE + 1];
   1278 	char *ret;
   1279 
   1280 	if (pcap_findalldevs(&alldevs, errbuf) == -1)
   1281 		return (NULL);
   1282 
   1283 	if (alldevs == NULL || (alldevs->flags & PCAP_IF_LOOPBACK)) {
   1284 		/*
   1285 		 * There are no devices on the list, or the first device
   1286 		 * on the list is a loopback device, which means there
   1287 		 * are no non-loopback devices on the list.  This means
   1288 		 * we can't return any device.
   1289 		 *
   1290 		 * XXX - why not return a loopback device?  If we can't
   1291 		 * capture on it, it won't be on the list, and if it's
   1292 		 * on the list, there aren't any non-loopback devices,
   1293 		 * so why not just supply it as the default device?
   1294 		 */
   1295 		(void)strlcpy(errbuf, "no suitable device found",
   1296 		    PCAP_ERRBUF_SIZE);
   1297 		ret = NULL;
   1298 	} else {
   1299 		/*
   1300 		 * Return the name of the first device on the list.
   1301 		 */
   1302 		(void)strlcpy(device, alldevs->name, sizeof(device));
   1303 		ret = device;
   1304 	}
   1305 
   1306 	pcap_freealldevs(alldevs);
   1307 	return (ret);
   1308 }
   1309 #endif /* !defined(HAVE_PACKET32) && !defined(MSDOS) */
   1310 
   1311 #if !defined(_WIN32) && !defined(MSDOS)
   1312 /*
   1313  * We don't just fetch the entire list of devices, search for the
   1314  * particular device, and use its first IPv4 address, as that's too
   1315  * much work to get just one device's netmask.
   1316  *
   1317  * If we had an API to get attributes for a given device, we could
   1318  * use that.
   1319  */
   1320 int
   1321 pcap_lookupnet(const char *device, bpf_u_int32 *netp, bpf_u_int32 *maskp,
   1322     char *errbuf)
   1323 {
   1324 	register int fd;
   1325 	register struct sockaddr_in *sin4;
   1326 	struct ifreq ifr;
   1327 
   1328 	/*
   1329 	 * The pseudo-device "any" listens on all interfaces and therefore
   1330 	 * has the network address and -mask "0.0.0.0" therefore catching
   1331 	 * all traffic. Using NULL for the interface is the same as "any".
   1332 	 */
   1333 	if (!device || strcmp(device, "any") == 0
   1334 #ifdef HAVE_DAG_API
   1335 	    || strstr(device, "dag") != NULL
   1336 #endif
   1337 #ifdef HAVE_SEPTEL_API
   1338 	    || strstr(device, "septel") != NULL
   1339 #endif
   1340 #ifdef PCAP_SUPPORT_BT
   1341 	    || strstr(device, "bluetooth") != NULL
   1342 #endif
   1343 #ifdef PCAP_SUPPORT_USB
   1344 	    || strstr(device, "usbmon") != NULL
   1345 #endif
   1346 #ifdef HAVE_SNF_API
   1347 	    || strstr(device, "snf") != NULL
   1348 #endif
   1349 #ifdef PCAP_SUPPORT_NETMAP
   1350 	    || strncmp(device, "netmap:", 7) == 0
   1351 	    || strncmp(device, "vale", 4) == 0
   1352 #endif
   1353 	    ) {
   1354 		*netp = *maskp = 0;
   1355 		return 0;
   1356 	}
   1357 
   1358 	fd = socket(AF_INET, SOCK_DGRAM, 0);
   1359 	if (fd < 0) {
   1360 		pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
   1361 		    errno, "socket");
   1362 		return (-1);
   1363 	}
   1364 	memset(&ifr, 0, sizeof(ifr));
   1365 #ifdef linux
   1366 	/* XXX Work around Linux kernel bug */
   1367 	ifr.ifr_addr.sa_family = AF_INET;
   1368 #endif
   1369 	(void)strlcpy(ifr.ifr_name, device, sizeof(ifr.ifr_name));
   1370 	if (ioctl(fd, SIOCGIFADDR, (char *)&ifr) < 0) {
   1371 		if (errno == EADDRNOTAVAIL) {
   1372 			(void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
   1373 			    "%s: no IPv4 address assigned", device);
   1374 		} else {
   1375 			pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
   1376 			    errno, "SIOCGIFADDR: %s", device);
   1377 		}
   1378 		(void)close(fd);
   1379 		return (-1);
   1380 	}
   1381 	sin4 = (struct sockaddr_in *)&ifr.ifr_addr;
   1382 	*netp = sin4->sin_addr.s_addr;
   1383 	memset(&ifr, 0, sizeof(ifr));
   1384 #ifdef linux
   1385 	/* XXX Work around Linux kernel bug */
   1386 	ifr.ifr_addr.sa_family = AF_INET;
   1387 #endif
   1388 	(void)strlcpy(ifr.ifr_name, device, sizeof(ifr.ifr_name));
   1389 	if (ioctl(fd, SIOCGIFNETMASK, (char *)&ifr) < 0) {
   1390 		pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
   1391 		    errno, "SIOCGIFNETMASK: %s", device);
   1392 		(void)close(fd);
   1393 		return (-1);
   1394 	}
   1395 	(void)close(fd);
   1396 	*maskp = sin4->sin_addr.s_addr;
   1397 	if (*maskp == 0) {
   1398 		if (IN_CLASSA(*netp))
   1399 			*maskp = IN_CLASSA_NET;
   1400 		else if (IN_CLASSB(*netp))
   1401 			*maskp = IN_CLASSB_NET;
   1402 		else if (IN_CLASSC(*netp))
   1403 			*maskp = IN_CLASSC_NET;
   1404 		else {
   1405 			(void)pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
   1406 			    "inet class for 0x%x unknown", *netp);
   1407 			return (-1);
   1408 		}
   1409 	}
   1410 	*netp &= *maskp;
   1411 	return (0);
   1412 }
   1413 #endif /* !defined(_WIN32) && !defined(MSDOS) */
   1414 
   1415 #ifdef ENABLE_REMOTE
   1416 #include "pcap-rpcap.h"
   1417 
   1418 /*
   1419  * Extract a substring from a string.
   1420  */
   1421 static char *
   1422 get_substring(const char *p, size_t len, char *ebuf)
   1423 {
   1424 	char *token;
   1425 
   1426 	token = malloc(len + 1);
   1427 	if (token == NULL) {
   1428 		pcap_fmt_errmsg_for_errno(ebuf, PCAP_ERRBUF_SIZE,
   1429 		    errno, "malloc");
   1430 		return (NULL);
   1431 	}
   1432 	memcpy(token, p, len);
   1433 	token[len] = '\0';
   1434 	return (token);
   1435 }
   1436 
   1437 /*
   1438  * Parse a capture source that might be a URL.
   1439  *
   1440  * If the source is not a URL, *schemep, *userinfop, *hostp, and *portp
   1441  * are set to NULL, *pathp is set to point to the source, and 0 is
   1442  * returned.
   1443  *
   1444  * If source is a URL, and the URL refers to a local device (a special
   1445  * case of rpcap:), *schemep, *userinfop, *hostp, and *portp are set
   1446  * to NULL, *pathp is set to point to the device name, and 0 is returned.
   1447  *
   1448  * If source is a URL, and it's not a special case that refers to a local
   1449  * device, and the parse succeeds:
   1450  *
   1451  *    *schemep is set to point to an allocated string containing the scheme;
   1452  *
   1453  *    if user information is present in the URL, *userinfop is set to point
   1454  *    to an allocated string containing the user information, otherwise
   1455  *    it's set to NULL;
   1456  *
   1457  *    if host information is present in the URL, *hostp is set to point
   1458  *    to an allocated string containing the host information, otherwise
   1459  *    it's set to NULL;
   1460  *
   1461  *    if a port number is present in the URL, *portp is set to point
   1462  *    to an allocated string containing the port number, otherwise
   1463  *    it's set to NULL;
   1464  *
   1465  *    *pathp is set to point to an allocated string containing the
   1466  *    path;
   1467  *
   1468  * and 0 is returned.
   1469  *
   1470  * If the parse fails, ebuf is set to an error string, and -1 is returned.
   1471  */
   1472 static int
   1473 pcap_parse_source(const char *source, char **schemep, char **userinfop,
   1474     char **hostp, char **portp, char **pathp, char *ebuf)
   1475 {
   1476 	char *colonp;
   1477 	size_t scheme_len;
   1478 	char *scheme;
   1479 	const char *endp;
   1480 	size_t authority_len;
   1481 	char *authority;
   1482 	char *parsep, *atsignp, *bracketp;
   1483 	char *userinfo, *host, *port, *path;
   1484 
   1485 	/*
   1486 	 * Start out returning nothing.
   1487 	 */
   1488 	*schemep = NULL;
   1489 	*userinfop = NULL;
   1490 	*hostp = NULL;
   1491 	*portp = NULL;
   1492 	*pathp = NULL;
   1493 
   1494 	/*
   1495 	 * RFC 3986 says:
   1496 	 *
   1497 	 *   URI         = scheme ":" hier-part [ "?" query ] [ "#" fragment ]
   1498 	 *
   1499 	 *   hier-part   = "//" authority path-abempty
   1500 	 *               / path-absolute
   1501 	 *               / path-rootless
   1502 	 *               / path-empty
   1503 	 *
   1504 	 *   authority   = [ userinfo "@" ] host [ ":" port ]
   1505 	 *
   1506 	 *   userinfo    = *( unreserved / pct-encoded / sub-delims / ":" )
   1507          *
   1508          * Step 1: look for the ":" at the end of the scheme.
   1509 	 * A colon in the source is *NOT* sufficient to indicate that
   1510 	 * this is a URL, as interface names on some platforms might
   1511 	 * include colons (e.g., I think some Solaris interfaces
   1512 	 * might).
   1513 	 */
   1514 	colonp = strchr(source, ':');
   1515 	if (colonp == NULL) {
   1516 		/*
   1517 		 * The source is the device to open.
   1518 		 * Return a NULL pointer for the scheme, user information,
   1519 		 * host, and port, and return the device as the path.
   1520 		 */
   1521 		*pathp = strdup(source);
   1522 		if (*pathp == NULL) {
   1523 			pcap_fmt_errmsg_for_errno(ebuf, PCAP_ERRBUF_SIZE,
   1524 			    errno, "malloc");
   1525 			return (-1);
   1526 		}
   1527 		return (0);
   1528 	}
   1529 
   1530 	/*
   1531 	 * All schemes must have "//" after them, i.e. we only support
   1532 	 * hier-part   = "//" authority path-abempty, not
   1533 	 * hier-part   = path-absolute
   1534 	 * hier-part   = path-rootless
   1535 	 * hier-part   = path-empty
   1536 	 *
   1537 	 * We need that in order to distinguish between a local device
   1538 	 * name that happens to contain a colon and a URI.
   1539 	 */
   1540 	if (strncmp(colonp + 1, "//", 2) != 0) {
   1541 		/*
   1542 		 * The source is the device to open.
   1543 		 * Return a NULL pointer for the scheme, user information,
   1544 		 * host, and port, and return the device as the path.
   1545 		 */
   1546 		*pathp = strdup(source);
   1547 		if (*pathp == NULL) {
   1548 			pcap_fmt_errmsg_for_errno(ebuf, PCAP_ERRBUF_SIZE,
   1549 			    errno, "malloc");
   1550 			return (-1);
   1551 		}
   1552 		return (0);
   1553 	}
   1554 
   1555 	/*
   1556 	 * XXX - check whether the purported scheme could be a scheme?
   1557 	 */
   1558 
   1559 	/*
   1560 	 * OK, this looks like a URL.
   1561 	 * Get the scheme.
   1562 	 */
   1563 	scheme_len = colonp - source;
   1564 	scheme = malloc(scheme_len + 1);
   1565 	if (scheme == NULL) {
   1566 		pcap_fmt_errmsg_for_errno(ebuf, PCAP_ERRBUF_SIZE,
   1567 		    errno, "malloc");
   1568 		return (-1);
   1569 	}
   1570 	memcpy(scheme, source, scheme_len);
   1571 	scheme[scheme_len] = '\0';
   1572 
   1573 	/*
   1574 	 * Treat file: specially - take everything after file:// as
   1575 	 * the pathname.
   1576 	 */
   1577 	if (pcap_strcasecmp(scheme, "file") == 0) {
   1578 		*schemep = scheme;
   1579 		*pathp = strdup(colonp + 3);
   1580 		if (*pathp == NULL) {
   1581 			pcap_fmt_errmsg_for_errno(ebuf, PCAP_ERRBUF_SIZE,
   1582 			    errno, "malloc");
   1583 			return (-1);
   1584 		}
   1585 		return (0);
   1586 	}
   1587 
   1588 	/*
   1589 	 * The WinPcap documentation says you can specify a local
   1590 	 * interface with "rpcap://{device}"; we special-case
   1591 	 * that here.  If the scheme is "rpcap", and there are
   1592 	 * no slashes past the "//", we just return the device.
   1593 	 *
   1594 	 * XXX - %-escaping?
   1595 	 */
   1596 	if (pcap_strcasecmp(scheme, "rpcap") == 0 &&
   1597 	    strchr(colonp + 3, '/') == NULL) {
   1598 		/*
   1599 		 * Local device.
   1600 		 *
   1601 		 * Return a NULL pointer for the scheme, user information,
   1602 		 * host, and port, and return the device as the path.
   1603 		 */
   1604 		free(scheme);
   1605 		*pathp = strdup(colonp + 3);
   1606 		if (*pathp == NULL) {
   1607 			pcap_fmt_errmsg_for_errno(ebuf, PCAP_ERRBUF_SIZE,
   1608 			    errno, "malloc");
   1609 			return (-1);
   1610 		}
   1611 		return (0);
   1612 	}
   1613 
   1614 	/*
   1615 	 * OK, now start parsing the authority.
   1616 	 * Get token, terminated with / or terminated at the end of
   1617 	 * the string.
   1618 	 */
   1619 	authority_len = strcspn(colonp + 3, "/");
   1620 	authority = get_substring(colonp + 3, authority_len, ebuf);
   1621 	if (authority == NULL) {
   1622 		/*
   1623 		 * Error.
   1624 		 */
   1625 		free(scheme);
   1626 		return (-1);
   1627 	}
   1628 	endp = colonp + 3 + authority_len;
   1629 
   1630 	/*
   1631 	 * Now carve the authority field into its components.
   1632 	 */
   1633 	parsep = authority;
   1634 
   1635 	/*
   1636 	 * Is there a userinfo field?
   1637 	 */
   1638 	atsignp = strchr(parsep, '@');
   1639 	if (atsignp != NULL) {
   1640 		/*
   1641 		 * Yes.
   1642 		 */
   1643 		size_t userinfo_len;
   1644 
   1645 		userinfo_len = atsignp - parsep;
   1646 		userinfo = get_substring(parsep, userinfo_len, ebuf);
   1647 		if (userinfo == NULL) {
   1648 			/*
   1649 			 * Error.
   1650 			 */
   1651 			free(authority);
   1652 			free(scheme);
   1653 			return (-1);
   1654 		}
   1655 		parsep = atsignp + 1;
   1656 	} else {
   1657 		/*
   1658 		 * No.
   1659 		 */
   1660 		userinfo = NULL;
   1661 	}
   1662 
   1663 	/*
   1664 	 * Is there a host field?
   1665 	 */
   1666 	if (*parsep == '\0') {
   1667 		/*
   1668 		 * No; there's no host field or port field.
   1669 		 */
   1670 		host = NULL;
   1671 		port = NULL;
   1672 	} else {
   1673 		/*
   1674 		 * Yes.
   1675 		 */
   1676 		size_t host_len;
   1677 
   1678 		/*
   1679 		 * Is it an IP-literal?
   1680 		 */
   1681 		if (*parsep == '[') {
   1682 			/*
   1683 			 * Yes.
   1684 			 * Treat verything up to the closing square
   1685 			 * bracket as the IP-Literal; we don't worry
   1686 			 * about whether it's a valid IPv6address or
   1687 			 * IPvFuture.
   1688 			 */
   1689 			bracketp = strchr(parsep, ']');
   1690 			if (bracketp == NULL) {
   1691 				/*
   1692 				 * There's no closing square bracket.
   1693 				 */
   1694 				pcap_snprintf(ebuf, PCAP_ERRBUF_SIZE,
   1695 				    "IP-literal in URL doesn't end with ]");
   1696 				free(userinfo);
   1697 				free(authority);
   1698 				free(scheme);
   1699 				return (-1);
   1700 			}
   1701 			if (*(bracketp + 1) != '\0' &&
   1702 			    *(bracketp + 1) != ':') {
   1703 				/*
   1704 				 * There's extra crud after the
   1705 				 * closing square bracketn.
   1706 				 */
   1707 				pcap_snprintf(ebuf, PCAP_ERRBUF_SIZE,
   1708 				    "Extra text after IP-literal in URL");
   1709 				free(userinfo);
   1710 				free(authority);
   1711 				free(scheme);
   1712 				return (-1);
   1713 			}
   1714 			host_len = (bracketp - 1) - parsep;
   1715 			host = get_substring(parsep + 1, host_len, ebuf);
   1716 			if (host == NULL) {
   1717 				/*
   1718 				 * Error.
   1719 				 */
   1720 				free(userinfo);
   1721 				free(authority);
   1722 				free(scheme);
   1723 				return (-1);
   1724 			}
   1725 			parsep = bracketp + 1;
   1726 		} else {
   1727 			/*
   1728 			 * No.
   1729 			 * Treat everything up to a : or the end of
   1730 			 * the string as the host.
   1731 			 */
   1732 			host_len = strcspn(parsep, ":");
   1733 			host = get_substring(parsep, host_len, ebuf);
   1734 			if (host == NULL) {
   1735 				/*
   1736 				 * Error.
   1737 				 */
   1738 				free(userinfo);
   1739 				free(authority);
   1740 				free(scheme);
   1741 				return (-1);
   1742 			}
   1743 			parsep = parsep + host_len;
   1744 		}
   1745 
   1746 		/*
   1747 		 * Is there a port field?
   1748 		 */
   1749 		if (*parsep == ':') {
   1750 			/*
   1751 			 * Yes.  It's the rest of the authority field.
   1752 			 */
   1753 			size_t port_len;
   1754 
   1755 			parsep++;
   1756 			port_len = strlen(parsep);
   1757 			port = get_substring(parsep, port_len, ebuf);
   1758 			if (port == NULL) {
   1759 				/*
   1760 				 * Error.
   1761 				 */
   1762 				free(host);
   1763 				free(userinfo);
   1764 				free(authority);
   1765 				free(scheme);
   1766 				return (-1);
   1767 			}
   1768 		} else {
   1769 			/*
   1770 			 * No.
   1771 			 */
   1772 			port = NULL;
   1773 		}
   1774 	}
   1775 	free(authority);
   1776 
   1777 	/*
   1778 	 * Everything else is the path.  Strip off the leading /.
   1779 	 */
   1780 	if (*endp == '\0')
   1781 		path = strdup("");
   1782 	else
   1783 		path = strdup(endp + 1);
   1784 	if (path == NULL) {
   1785 		pcap_fmt_errmsg_for_errno(ebuf, PCAP_ERRBUF_SIZE,
   1786 		    errno, "malloc");
   1787 		free(port);
   1788 		free(host);
   1789 		free(userinfo);
   1790 		free(scheme);
   1791 		return (-1);
   1792 	}
   1793 	*schemep = scheme;
   1794 	*userinfop = userinfo;
   1795 	*hostp = host;
   1796 	*portp = port;
   1797 	*pathp = path;
   1798 	return (0);
   1799 }
   1800 
   1801 int
   1802 pcap_createsrcstr(char *source, int type, const char *host, const char *port,
   1803     const char *name, char *errbuf)
   1804 {
   1805 	switch (type) {
   1806 
   1807 	case PCAP_SRC_FILE:
   1808 		strlcpy(source, PCAP_SRC_FILE_STRING, PCAP_BUF_SIZE);
   1809 		if (name != NULL && *name != '\0') {
   1810 			strlcat(source, name, PCAP_BUF_SIZE);
   1811 			return (0);
   1812 		} else {
   1813 			pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
   1814 			    "The file name cannot be NULL.");
   1815 			return (-1);
   1816 		}
   1817 
   1818 	case PCAP_SRC_IFREMOTE:
   1819 		strlcpy(source, PCAP_SRC_IF_STRING, PCAP_BUF_SIZE);
   1820 		if (host != NULL && *host != '\0') {
   1821 			if (strchr(host, ':') != NULL) {
   1822 				/*
   1823 				 * The host name contains a colon, so it's
   1824 				 * probably an IPv6 address, and needs to
   1825 				 * be included in square brackets.
   1826 				 */
   1827 				strlcat(source, "[", PCAP_BUF_SIZE);
   1828 				strlcat(source, host, PCAP_BUF_SIZE);
   1829 				strlcat(source, "]", PCAP_BUF_SIZE);
   1830 			} else
   1831 				strlcat(source, host, PCAP_BUF_SIZE);
   1832 
   1833 			if (port != NULL && *port != '\0') {
   1834 				strlcat(source, ":", PCAP_BUF_SIZE);
   1835 				strlcat(source, port, PCAP_BUF_SIZE);
   1836 			}
   1837 
   1838 			strlcat(source, "/", PCAP_BUF_SIZE);
   1839 		} else {
   1840 			pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
   1841 			    "The host name cannot be NULL.");
   1842 			return (-1);
   1843 		}
   1844 
   1845 		if (name != NULL && *name != '\0')
   1846 			strlcat(source, name, PCAP_BUF_SIZE);
   1847 
   1848 		return (0);
   1849 
   1850 	case PCAP_SRC_IFLOCAL:
   1851 		strlcpy(source, PCAP_SRC_IF_STRING, PCAP_BUF_SIZE);
   1852 
   1853 		if (name != NULL && *name != '\0')
   1854 			strlcat(source, name, PCAP_BUF_SIZE);
   1855 
   1856 		return (0);
   1857 
   1858 	default:
   1859 		pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE,
   1860 		    "The interface type is not valid.");
   1861 		return (-1);
   1862 	}
   1863 }
   1864 
   1865 int
   1866 pcap_parsesrcstr(const char *source, int *type, char *host, char *port,
   1867     char *name, char *errbuf)
   1868 {
   1869 	char *scheme, *tmpuserinfo, *tmphost, *tmpport, *tmppath;
   1870 
   1871 	/* Initialization stuff */
   1872 	if (host)
   1873 		*host = '\0';
   1874 	if (port)
   1875 		*port = '\0';
   1876 	if (name)
   1877 		*name = '\0';
   1878 
   1879 	/* Parse the source string */
   1880 	if (pcap_parse_source(source, &scheme, &tmpuserinfo, &tmphost,
   1881 	    &tmpport, &tmppath, errbuf) == -1) {
   1882 		/*
   1883 		 * Fail.
   1884 		 */
   1885 		return (-1);
   1886 	}
   1887 
   1888 	if (scheme == NULL) {
   1889 		/*
   1890 		 * Local device.
   1891 		 */
   1892 		if (name && tmppath)
   1893 			strlcpy(name, tmppath, PCAP_BUF_SIZE);
   1894 		if (type)
   1895 			*type = PCAP_SRC_IFLOCAL;
   1896 		free(tmppath);
   1897 		free(tmpport);
   1898 		free(tmphost);
   1899 		free(tmpuserinfo);
   1900 		return (0);
   1901 	}
   1902 
   1903 	if (strcmp(scheme, "rpcap") == 0) {
   1904 		/*
   1905 		 * rpcap://
   1906 		 *
   1907 		 * pcap_parse_source() has already handled the case of
   1908 		 * rpcap://device
   1909 		 */
   1910 		if (host && tmphost) {
   1911 			if (tmpuserinfo)
   1912 				pcap_snprintf(host, PCAP_BUF_SIZE, "%s@%s",
   1913 				    tmpuserinfo, tmphost);
   1914 			else
   1915 				strlcpy(host, tmphost, PCAP_BUF_SIZE);
   1916 		}
   1917 		if (port && tmpport)
   1918 			strlcpy(port, tmpport, PCAP_BUF_SIZE);
   1919 		if (name && tmppath)
   1920 			strlcpy(name, tmppath, PCAP_BUF_SIZE);
   1921 		if (type)
   1922 			*type = PCAP_SRC_IFREMOTE;
   1923 		free(tmppath);
   1924 		free(tmpport);
   1925 		free(tmphost);
   1926 		free(tmpuserinfo);
   1927 		free(scheme);
   1928 		return (0);
   1929 	}
   1930 
   1931 	if (strcmp(scheme, "file") == 0) {
   1932 		/*
   1933 		 * file://
   1934 		 */
   1935 		if (name && tmppath)
   1936 			strlcpy(name, tmppath, PCAP_BUF_SIZE);
   1937 		if (type)
   1938 			*type = PCAP_SRC_FILE;
   1939 		free(tmppath);
   1940 		free(tmpport);
   1941 		free(tmphost);
   1942 		free(tmpuserinfo);
   1943 		free(scheme);
   1944 		return (0);
   1945 	}
   1946 
   1947 	/*
   1948 	 * Neither rpcap: nor file:; just treat the entire string
   1949 	 * as a local device.
   1950 	 */
   1951 	if (name)
   1952 		strlcpy(name, source, PCAP_BUF_SIZE);
   1953 	if (type)
   1954 		*type = PCAP_SRC_IFLOCAL;
   1955 	free(tmppath);
   1956 	free(tmpport);
   1957 	free(tmphost);
   1958 	free(tmpuserinfo);
   1959 	free(scheme);
   1960 	return (0);
   1961 }
   1962 #endif
   1963 
   1964 pcap_t *
   1965 pcap_create(const char *device, char *errbuf)
   1966 {
   1967 	size_t i;
   1968 	int is_theirs;
   1969 	pcap_t *p;
   1970 	char *device_str;
   1971 
   1972 	/*
   1973 	 * A null device name is equivalent to the "any" device -
   1974 	 * which might not be supported on this platform, but
   1975 	 * this means that you'll get a "not supported" error
   1976 	 * rather than, say, a crash when we try to dereference
   1977 	 * the null pointer.
   1978 	 */
   1979 	if (device == NULL)
   1980 		device_str = strdup("any");
   1981 	else {
   1982 #ifdef _WIN32
   1983 		/*
   1984 		 * If the string appears to be little-endian UCS-2/UTF-16,
   1985 		 * convert it to ASCII.
   1986 		 *
   1987 		 * XXX - to UTF-8 instead?  Or report an error if any
   1988 		 * character isn't ASCII?
   1989 		 */
   1990 		if (device[0] != '\0' && device[1] == '\0') {
   1991 			size_t length;
   1992 
   1993 			length = wcslen((wchar_t *)device);
   1994 			device_str = (char *)malloc(length + 1);
   1995 			if (device_str == NULL) {
   1996 				pcap_fmt_errmsg_for_errno(errbuf,
   1997 				    PCAP_ERRBUF_SIZE, errno,
   1998 				    "malloc");
   1999 				return (NULL);
   2000 			}
   2001 
   2002 			pcap_snprintf(device_str, length + 1, "%ws",
   2003 			    (const wchar_t *)device);
   2004 		} else
   2005 #endif
   2006 			device_str = strdup(device);
   2007 	}
   2008 	if (device_str == NULL) {
   2009 		pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE,
   2010 		    errno, "malloc");
   2011 		return (NULL);
   2012 	}
   2013 
   2014 	/*
   2015 	 * Try each of the non-local-network-interface capture
   2016 	 * source types until we find one that works for this
   2017 	 * device or run out of types.
   2018 	 */
   2019 	for (i = 0; capture_source_types[i].create_op != NULL; i++) {
   2020 		is_theirs = 0;
   2021 		p = capture_source_types[i].create_op(device_str, errbuf,
   2022 		    &is_theirs);
   2023 		if (is_theirs) {
   2024 			/*
   2025 			 * The device name refers to a device of the
   2026 			 * type in question; either it succeeded,
   2027 			 * in which case p refers to a pcap_t to
   2028 			 * later activate for the device, or it
   2029 			 * failed, in which case p is null and we
   2030 			 * should return that to report the failure
   2031 			 * to create.
   2032 			 */
   2033 			if (p == NULL) {
   2034 				/*
   2035 				 * We assume the caller filled in errbuf.
   2036 				 */
   2037 				free(device_str);
   2038 				return (NULL);
   2039 			}
   2040 			p->opt.device = device_str;
   2041 			return (p);
   2042 		}
   2043 	}
   2044 
   2045 	/*
   2046 	 * OK, try it as a regular network interface.
   2047 	 */
   2048 	p = pcap_create_interface(device_str, errbuf);
   2049 	if (p == NULL) {
   2050 		/*
   2051 		 * We assume the caller filled in errbuf.
   2052 		 */
   2053 		free(device_str);
   2054 		return (NULL);
   2055 	}
   2056 	p->opt.device = device_str;
   2057 	return (p);
   2058 }
   2059 
   2060 /*
   2061  * Set nonblocking mode on an unactivated pcap_t; this sets a flag
   2062  * checked by pcap_activate(), which sets the mode after calling
   2063  * the activate routine.
   2064  */
   2065 static int
   2066 pcap_setnonblock_unactivated(pcap_t *p, int nonblock)
   2067 {
   2068 	p->opt.nonblock = nonblock;
   2069 	return (0);
   2070 }
   2071 
   2072 static void
   2073 initialize_ops(pcap_t *p)
   2074 {
   2075 	/*
   2076 	 * Set operation pointers for operations that only work on
   2077 	 * an activated pcap_t to point to a routine that returns
   2078 	 * a "this isn't activated" error.
   2079 	 */
   2080 	p->read_op = (read_op_t)pcap_not_initialized;
   2081 	p->inject_op = (inject_op_t)pcap_not_initialized;
   2082 	p->setfilter_op = (setfilter_op_t)pcap_not_initialized;
   2083 	p->setdirection_op = (setdirection_op_t)pcap_not_initialized;
   2084 	p->set_datalink_op = (set_datalink_op_t)pcap_not_initialized;
   2085 	p->getnonblock_op = (getnonblock_op_t)pcap_not_initialized;
   2086 	p->stats_op = (stats_op_t)pcap_not_initialized;
   2087 #ifdef _WIN32
   2088 	p->stats_ex_op = (stats_ex_op_t)pcap_not_initialized_ptr;
   2089 	p->setbuff_op = (setbuff_op_t)pcap_not_initialized;
   2090 	p->setmode_op = (setmode_op_t)pcap_not_initialized;
   2091 	p->setmintocopy_op = (setmintocopy_op_t)pcap_not_initialized;
   2092 	p->getevent_op = pcap_getevent_not_initialized;
   2093 	p->oid_get_request_op = (oid_get_request_op_t)pcap_not_initialized;
   2094 	p->oid_set_request_op = (oid_set_request_op_t)pcap_not_initialized;
   2095 	p->sendqueue_transmit_op = pcap_sendqueue_transmit_not_initialized;
   2096 	p->setuserbuffer_op = (setuserbuffer_op_t)pcap_not_initialized;
   2097 	p->live_dump_op = (live_dump_op_t)pcap_not_initialized;
   2098 	p->live_dump_ended_op = (live_dump_ended_op_t)pcap_not_initialized;
   2099 	p->get_airpcap_handle_op = pcap_get_airpcap_handle_not_initialized;
   2100 #endif
   2101 
   2102 	/*
   2103 	 * Default cleanup operation - implementations can override
   2104 	 * this, but should call pcap_cleanup_live_common() after
   2105 	 * doing their own additional cleanup.
   2106 	 */
   2107 	p->cleanup_op = pcap_cleanup_live_common;
   2108 
   2109 	/*
   2110 	 * In most cases, the standard one-shot callback can
   2111 	 * be used for pcap_next()/pcap_next_ex().
   2112 	 */
   2113 	p->oneshot_callback = pcap_oneshot;
   2114 }
   2115 
   2116 static pcap_t *
   2117 pcap_alloc_pcap_t(char *ebuf, size_t size)
   2118 {
   2119 	char *chunk;
   2120 	pcap_t *p;
   2121 
   2122 	/*
   2123 	 * Allocate a chunk of memory big enough for a pcap_t
   2124 	 * plus a structure following it of size "size".  The
   2125 	 * structure following it is a private data structure
   2126 	 * for the routines that handle this pcap_t.
   2127 	 *
   2128 	 * The structure following it must be aligned on
   2129 	 * the appropriate alignment boundary for this platform.
   2130 	 * We align on an 8-byte boundary as that's probably what
   2131 	 * at least some platforms do, even with 32-bit integers,
   2132 	 * and because we can't be sure that some values won't
   2133 	 * require 8-byte alignment even on platforms with 32-bit
   2134 	 * integers.
   2135 	 */
   2136 #define PCAP_T_ALIGNED_SIZE	((sizeof(pcap_t) + 7) & ~0x7)
   2137 	chunk = malloc(PCAP_T_ALIGNED_SIZE + size);
   2138 	if (chunk == NULL) {
   2139 		pcap_fmt_errmsg_for_errno(ebuf, PCAP_ERRBUF_SIZE,
   2140 		    errno, "malloc");
   2141 		return (NULL);
   2142 	}
   2143 	memset(chunk, 0, PCAP_T_ALIGNED_SIZE + size);
   2144 
   2145 	/*
   2146 	 * Get a pointer to the pcap_t at the beginning.
   2147 	 */
   2148 	p = (pcap_t *)chunk;
   2149 
   2150 #ifdef _WIN32
   2151 	p->handle = INVALID_HANDLE_VALUE;	/* not opened yet */
   2152 #else /* _WIN32 */
   2153 	p->fd = -1;	/* not opened yet */
   2154 #ifndef MSDOS
   2155 	p->selectable_fd = -1;
   2156 	p->required_select_timeout = NULL;
   2157 #endif /* MSDOS */
   2158 #endif /* _WIN32 */
   2159 
   2160 	if (size == 0) {
   2161 		/* No private data was requested. */
   2162 		p->priv = NULL;
   2163 	} else {
   2164 		/*
   2165 		 * Set the pointer to the private data; that's the structure
   2166 		 * of size "size" following the pcap_t.
   2167 		 */
   2168 		p->priv = (void *)(chunk + PCAP_T_ALIGNED_SIZE);
   2169 	}
   2170 
   2171 	return (p);
   2172 }
   2173 
   2174 pcap_t *
   2175 pcap_create_common(char *ebuf, size_t size)
   2176 {
   2177 	pcap_t *p;
   2178 
   2179 	p = pcap_alloc_pcap_t(ebuf, size);
   2180 	if (p == NULL)
   2181 		return (NULL);
   2182 
   2183 	/*
   2184 	 * Default to "can't set rfmon mode"; if it's supported by
   2185 	 * a platform, the create routine that called us can set
   2186 	 * the op to its routine to check whether a particular
   2187 	 * device supports it.
   2188 	 */
   2189 	p->can_set_rfmon_op = pcap_cant_set_rfmon;
   2190 
   2191 	/*
   2192 	 * If pcap_setnonblock() is called on a not-yet-activated
   2193 	 * pcap_t, default to setting a flag and turning
   2194 	 * on non-blocking mode when activated.
   2195 	 */
   2196 	p->setnonblock_op = pcap_setnonblock_unactivated;
   2197 
   2198 	initialize_ops(p);
   2199 
   2200 	/* put in some defaults*/
   2201 	p->snapshot = 0;		/* max packet size unspecified */
   2202 	p->opt.timeout = 0;		/* no timeout specified */
   2203 	p->opt.buffer_size = 0;		/* use the platform's default */
   2204 	p->opt.promisc = 0;
   2205 	p->opt.rfmon = 0;
   2206 	p->opt.immediate = 0;
   2207 	p->opt.tstamp_type = -1;	/* default to not setting time stamp type */
   2208 	p->opt.tstamp_precision = PCAP_TSTAMP_PRECISION_MICRO;
   2209 	/*
   2210 	 * Platform-dependent options.
   2211 	 */
   2212 #ifdef __linux__
   2213 	p->opt.protocol = 0;
   2214 #endif
   2215 #ifdef _WIN32
   2216 	p->opt.nocapture_local = 0;
   2217 #endif
   2218 
   2219 	/*
   2220 	 * Start out with no BPF code generation flags set.
   2221 	 */
   2222 	p->bpf_codegen_flags = 0;
   2223 
   2224 	return (p);
   2225 }
   2226 
   2227 int
   2228 pcap_check_activated(pcap_t *p)
   2229 {
   2230 	if (p->activated) {
   2231 		pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "can't perform "
   2232 			" operation on activated capture");
   2233 		return (-1);
   2234 	}
   2235 	return (0);
   2236 }
   2237 
   2238 int
   2239 pcap_set_snaplen(pcap_t *p, int snaplen)
   2240 {
   2241 	if (pcap_check_activated(p))
   2242 		return (PCAP_ERROR_ACTIVATED);
   2243 	p->snapshot = snaplen;
   2244 	return (0);
   2245 }
   2246 
   2247 int
   2248 pcap_set_promisc(pcap_t *p, int promisc)
   2249 {
   2250 	if (pcap_check_activated(p))
   2251 		return (PCAP_ERROR_ACTIVATED);
   2252 	p->opt.promisc = promisc;
   2253 	return (0);
   2254 }
   2255 
   2256 int
   2257 pcap_set_rfmon(pcap_t *p, int rfmon)
   2258 {
   2259 	if (pcap_check_activated(p))
   2260 		return (PCAP_ERROR_ACTIVATED);
   2261 	p->opt.rfmon = rfmon;
   2262 	return (0);
   2263 }
   2264 
   2265 int
   2266 pcap_set_timeout(pcap_t *p, int timeout_ms)
   2267 {
   2268 	if (pcap_check_activated(p))
   2269 		return (PCAP_ERROR_ACTIVATED);
   2270 	p->opt.timeout = timeout_ms;
   2271 	return (0);
   2272 }
   2273 
   2274 int
   2275 pcap_set_tstamp_type(pcap_t *p, int tstamp_type)
   2276 {
   2277 	int i;
   2278 
   2279 	if (pcap_check_activated(p))
   2280 		return (PCAP_ERROR_ACTIVATED);
   2281 
   2282 	/*
   2283 	 * The argument should have been u_int, but that's too late
   2284 	 * to change now - it's an API.
   2285 	 */
   2286 	if (tstamp_type < 0)
   2287 		return (PCAP_WARNING_TSTAMP_TYPE_NOTSUP);
   2288 
   2289 	/*
   2290 	 * If p->tstamp_type_count is 0, we only support PCAP_TSTAMP_HOST;
   2291 	 * the default time stamp type is PCAP_TSTAMP_HOST.
   2292 	 */
   2293 	if (p->tstamp_type_count == 0) {
   2294 		if (tstamp_type == PCAP_TSTAMP_HOST) {
   2295 			p->opt.tstamp_type = tstamp_type;
   2296 			return (0);
   2297 		}
   2298 	} else {
   2299 		/*
   2300 		 * Check whether we claim to support this type of time stamp.
   2301 		 */
   2302 		for (i = 0; i < p->tstamp_type_count; i++) {
   2303 			if (p->tstamp_type_list[i] == (u_int)tstamp_type) {
   2304 				/*
   2305 				 * Yes.
   2306 				 */
   2307 				p->opt.tstamp_type = tstamp_type;
   2308 				return (0);
   2309 			}
   2310 		}
   2311 	}
   2312 
   2313 	/*
   2314 	 * We don't support this type of time stamp.
   2315 	 */
   2316 	return (PCAP_WARNING_TSTAMP_TYPE_NOTSUP);
   2317 }
   2318 
   2319 int
   2320 pcap_set_immediate_mode(pcap_t *p, int immediate)
   2321 {
   2322 	if (pcap_check_activated(p))
   2323 		return (PCAP_ERROR_ACTIVATED);
   2324 	p->opt.immediate = immediate;
   2325 	return (0);
   2326 }
   2327 
   2328 int
   2329 pcap_set_buffer_size(pcap_t *p, int buffer_size)
   2330 {
   2331 	if (pcap_check_activated(p))
   2332 		return (PCAP_ERROR_ACTIVATED);
   2333 	if (buffer_size <= 0) {
   2334 		/*
   2335 		 * Silently ignore invalid values.
   2336 		 */
   2337 		return (0);
   2338 	}
   2339 	p->opt.buffer_size = buffer_size;
   2340 	return (0);
   2341 }
   2342 
   2343 int
   2344 pcap_set_tstamp_precision(pcap_t *p, int tstamp_precision)
   2345 {
   2346 	int i;
   2347 
   2348 	if (pcap_check_activated(p))
   2349 		return (PCAP_ERROR_ACTIVATED);
   2350 
   2351 	/*
   2352 	 * The argument should have been u_int, but that's too late
   2353 	 * to change now - it's an API.
   2354 	 */
   2355 	if (tstamp_precision < 0)
   2356 		return (PCAP_ERROR_TSTAMP_PRECISION_NOTSUP);
   2357 
   2358 	/*
   2359 	 * If p->tstamp_precision_count is 0, we only support setting
   2360 	 * the time stamp precision to microsecond precision; every
   2361 	 * pcap module *MUST* support microsecond precision, even if
   2362 	 * it does so by converting the native precision to
   2363 	 * microseconds.
   2364 	 */
   2365 	if (p->tstamp_precision_count == 0) {
   2366 		if (tstamp_precision == PCAP_TSTAMP_PRECISION_MICRO) {
   2367 			p->opt.tstamp_precision = tstamp_precision;
   2368 			return (0);
   2369 		}
   2370 	} else {
   2371 		/*
   2372 		 * Check whether we claim to support this precision of
   2373 		 * time stamp.
   2374 		 */
   2375 		for (i = 0; i < p->tstamp_precision_count; i++) {
   2376 			if (p->tstamp_precision_list[i] == (u_int)tstamp_precision) {
   2377 				/*
   2378 				 * Yes.
   2379 				 */
   2380 				p->opt.tstamp_precision = tstamp_precision;
   2381 				return (0);
   2382 			}
   2383 		}
   2384 	}
   2385 
   2386 	/*
   2387 	 * We don't support this time stamp precision.
   2388 	 */
   2389 	return (PCAP_ERROR_TSTAMP_PRECISION_NOTSUP);
   2390 }
   2391 
   2392 int
   2393 pcap_get_tstamp_precision(pcap_t *p)
   2394 {
   2395         return (p->opt.tstamp_precision);
   2396 }
   2397 
   2398 int
   2399 pcap_activate(pcap_t *p)
   2400 {
   2401 	int status;
   2402 
   2403 	/*
   2404 	 * Catch attempts to re-activate an already-activated
   2405 	 * pcap_t; this should, for example, catch code that
   2406 	 * calls pcap_open_live() followed by pcap_activate(),
   2407 	 * as some code that showed up in a Stack Exchange
   2408 	 * question did.
   2409 	 */
   2410 	if (pcap_check_activated(p))
   2411 		return (PCAP_ERROR_ACTIVATED);
   2412 	status = p->activate_op(p);
   2413 	if (status >= 0) {
   2414 		/*
   2415 		 * If somebody requested non-blocking mode before
   2416 		 * calling pcap_activate(), turn it on now.
   2417 		 */
   2418 		if (p->opt.nonblock) {
   2419 			status = p->setnonblock_op(p, 1);
   2420 			if (status < 0) {
   2421 				/*
   2422 				 * Failed.  Undo everything done by
   2423 				 * the activate operation.
   2424 				 */
   2425 				p->cleanup_op(p);
   2426 				initialize_ops(p);
   2427 				return (status);
   2428 			}
   2429 		}
   2430 		p->activated = 1;
   2431 	} else {
   2432 		if (p->errbuf[0] == '\0') {
   2433 			/*
   2434 			 * No error message supplied by the activate routine;
   2435 			 * for the benefit of programs that don't specially
   2436 			 * handle errors other than PCAP_ERROR, return the
   2437 			 * error message corresponding to the status.
   2438 			 */
   2439 			pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "%s",
   2440 			    pcap_statustostr(status));
   2441 		}
   2442 
   2443 		/*
   2444 		 * Undo any operation pointer setting, etc. done by
   2445 		 * the activate operation.
   2446 		 */
   2447 		initialize_ops(p);
   2448 	}
   2449 	return (status);
   2450 }
   2451 
   2452 pcap_t *
   2453 pcap_open_live(const char *device, int snaplen, int promisc, int to_ms, char *errbuf)
   2454 {
   2455 	pcap_t *p;
   2456 	int status;
   2457 #ifdef ENABLE_REMOTE
   2458 	char host[PCAP_BUF_SIZE + 1];
   2459 	char port[PCAP_BUF_SIZE + 1];
   2460 	char name[PCAP_BUF_SIZE + 1];
   2461 	int srctype;
   2462 
   2463 	/*
   2464 	 * Retrofit - we have to make older applications compatible with
   2465 	 * remote capture.
   2466 	 * So we're calling pcap_open_remote() from here; this is a very
   2467 	 * dirty hack.
   2468 	 * Obviously, we cannot exploit all the new features; for instance,
   2469 	 * we cannot send authentication, we cannot use a UDP data connection,
   2470 	 * and so on.
   2471 	 */
   2472 	if (pcap_parsesrcstr(device, &srctype, host, port, name, errbuf))
   2473 		return (NULL);
   2474 
   2475 	if (srctype == PCAP_SRC_IFREMOTE) {
   2476 		/*
   2477 		 * Although we already have host, port and iface, we prefer
   2478 		 * to pass only 'device' to pcap_open_rpcap(), so that it has
   2479 		 * to call pcap_parsesrcstr() again.
   2480 		 * This is less optimized, but much clearer.
   2481 		 */
   2482 		return (pcap_open_rpcap(device, snaplen,
   2483 		    promisc ? PCAP_OPENFLAG_PROMISCUOUS : 0, to_ms,
   2484 		    NULL, errbuf));
   2485 	}
   2486 	if (srctype == PCAP_SRC_FILE) {
   2487 		pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE, "unknown URL scheme \"file\"");
   2488 		return (NULL);
   2489 	}
   2490 	if (srctype == PCAP_SRC_IFLOCAL) {
   2491 		/*
   2492 		 * If it starts with rpcap://, that refers to a local device
   2493 		 * (no host part in the URL). Remove the rpcap://, and
   2494 		 * fall through to the regular open path.
   2495 		 */
   2496 		if (strncmp(device, PCAP_SRC_IF_STRING, strlen(PCAP_SRC_IF_STRING)) == 0) {
   2497 			size_t len = strlen(device) - strlen(PCAP_SRC_IF_STRING) + 1;
   2498 
   2499 			if (len > 0)
   2500 				device += strlen(PCAP_SRC_IF_STRING);
   2501 		}
   2502 	}
   2503 #endif	/* ENABLE_REMOTE */
   2504 
   2505 	p = pcap_create(device, errbuf);
   2506 	if (p == NULL)
   2507 		return (NULL);
   2508 	status = pcap_set_snaplen(p, snaplen);
   2509 	if (status < 0)
   2510 		goto fail;
   2511 	status = pcap_set_promisc(p, promisc);
   2512 	if (status < 0)
   2513 		goto fail;
   2514 	status = pcap_set_timeout(p, to_ms);
   2515 	if (status < 0)
   2516 		goto fail;
   2517 	/*
   2518 	 * Mark this as opened with pcap_open_live(), so that, for
   2519 	 * example, we show the full list of DLT_ values, rather
   2520 	 * than just the ones that are compatible with capturing
   2521 	 * when not in monitor mode.  That allows existing applications
   2522 	 * to work the way they used to work, but allows new applications
   2523 	 * that know about the new open API to, for example, find out the
   2524 	 * DLT_ values that they can select without changing whether
   2525 	 * the adapter is in monitor mode or not.
   2526 	 */
   2527 	p->oldstyle = 1;
   2528 	status = pcap_activate(p);
   2529 	if (status < 0)
   2530 		goto fail;
   2531 	return (p);
   2532 fail:
   2533 	if (status == PCAP_ERROR)
   2534 		pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE, "%s: %s", device,
   2535 		    p->errbuf);
   2536 	else if (status == PCAP_ERROR_NO_SUCH_DEVICE ||
   2537 	    status == PCAP_ERROR_PERM_DENIED ||
   2538 	    status == PCAP_ERROR_PROMISC_PERM_DENIED)
   2539 		pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE, "%s: %s (%s)", device,
   2540 		    pcap_statustostr(status), p->errbuf);
   2541 	else
   2542 		pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE, "%s: %s", device,
   2543 		    pcap_statustostr(status));
   2544 	pcap_close(p);
   2545 	return (NULL);
   2546 }
   2547 
   2548 pcap_t *
   2549 pcap_open_offline_common(char *ebuf, size_t size)
   2550 {
   2551 	pcap_t *p;
   2552 
   2553 	p = pcap_alloc_pcap_t(ebuf, size);
   2554 	if (p == NULL)
   2555 		return (NULL);
   2556 
   2557 	p->opt.tstamp_precision = PCAP_TSTAMP_PRECISION_MICRO;
   2558 
   2559 	return (p);
   2560 }
   2561 
   2562 int
   2563 pcap_dispatch(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
   2564 {
   2565 	return (p->read_op(p, cnt, callback, user));
   2566 }
   2567 
   2568 int
   2569 pcap_loop(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
   2570 {
   2571 	register int n;
   2572 
   2573 	for (;;) {
   2574 		if (p->rfile != NULL) {
   2575 			/*
   2576 			 * 0 means EOF, so don't loop if we get 0.
   2577 			 */
   2578 			n = pcap_offline_read(p, cnt, callback, user);
   2579 		} else {
   2580 			/*
   2581 			 * XXX keep reading until we get something
   2582 			 * (or an error occurs)
   2583 			 */
   2584 			do {
   2585 				n = p->read_op(p, cnt, callback, user);
   2586 			} while (n == 0);
   2587 		}
   2588 		if (n <= 0)
   2589 			return (n);
   2590 		if (!PACKET_COUNT_IS_UNLIMITED(cnt)) {
   2591 			cnt -= n;
   2592 			if (cnt <= 0)
   2593 				return (0);
   2594 		}
   2595 	}
   2596 }
   2597 
   2598 /*
   2599  * Force the loop in "pcap_read()" or "pcap_read_offline()" to terminate.
   2600  */
   2601 void
   2602 pcap_breakloop(pcap_t *p)
   2603 {
   2604 	p->break_loop = 1;
   2605 }
   2606 
   2607 int
   2608 pcap_datalink(pcap_t *p)
   2609 {
   2610 	if (!p->activated)
   2611 		return (PCAP_ERROR_NOT_ACTIVATED);
   2612 	return (p->linktype);
   2613 }
   2614 
   2615 int
   2616 pcap_datalink_ext(pcap_t *p)
   2617 {
   2618 	if (!p->activated)
   2619 		return (PCAP_ERROR_NOT_ACTIVATED);
   2620 	return (p->linktype_ext);
   2621 }
   2622 
   2623 int
   2624 pcap_list_datalinks(pcap_t *p, int **dlt_buffer)
   2625 {
   2626 	if (!p->activated)
   2627 		return (PCAP_ERROR_NOT_ACTIVATED);
   2628 	if (p->dlt_count == 0) {
   2629 		/*
   2630 		 * We couldn't fetch the list of DLTs, which means
   2631 		 * this platform doesn't support changing the
   2632 		 * DLT for an interface.  Return a list of DLTs
   2633 		 * containing only the DLT this device supports.
   2634 		 */
   2635 		*dlt_buffer = (int*)malloc(sizeof(**dlt_buffer));
   2636 		if (*dlt_buffer == NULL) {
   2637 			pcap_fmt_errmsg_for_errno(p->errbuf, sizeof(p->errbuf),
   2638 			    errno, "malloc");
   2639 			return (PCAP_ERROR);
   2640 		}
   2641 		**dlt_buffer = p->linktype;
   2642 		return (1);
   2643 	} else {
   2644 		*dlt_buffer = (int*)calloc(sizeof(**dlt_buffer), p->dlt_count);
   2645 		if (*dlt_buffer == NULL) {
   2646 			pcap_fmt_errmsg_for_errno(p->errbuf, sizeof(p->errbuf),
   2647 			    errno, "malloc");
   2648 			return (PCAP_ERROR);
   2649 		}
   2650 		(void)memcpy(*dlt_buffer, p->dlt_list,
   2651 		    sizeof(**dlt_buffer) * p->dlt_count);
   2652 		return (p->dlt_count);
   2653 	}
   2654 }
   2655 
   2656 /*
   2657  * In Windows, you might have a library built with one version of the
   2658  * C runtime library and an application built with another version of
   2659  * the C runtime library, which means that the library might use one
   2660  * version of malloc() and free() and the application might use another
   2661  * version of malloc() and free().  If so, that means something
   2662  * allocated by the library cannot be freed by the application, so we
   2663  * need to have a pcap_free_datalinks() routine to free up the list
   2664  * allocated by pcap_list_datalinks(), even though it's just a wrapper
   2665  * around free().
   2666  */
   2667 void
   2668 pcap_free_datalinks(int *dlt_list)
   2669 {
   2670 	free(dlt_list);
   2671 }
   2672 
   2673 int
   2674 pcap_set_datalink(pcap_t *p, int dlt)
   2675 {
   2676 	int i;
   2677 	const char *dlt_name;
   2678 
   2679 	if (dlt < 0)
   2680 		goto unsupported;
   2681 
   2682 	if (p->dlt_count == 0 || p->set_datalink_op == NULL) {
   2683 		/*
   2684 		 * We couldn't fetch the list of DLTs, or we don't
   2685 		 * have a "set datalink" operation, which means
   2686 		 * this platform doesn't support changing the
   2687 		 * DLT for an interface.  Check whether the new
   2688 		 * DLT is the one this interface supports.
   2689 		 */
   2690 		if (p->linktype != dlt)
   2691 			goto unsupported;
   2692 
   2693 		/*
   2694 		 * It is, so there's nothing we need to do here.
   2695 		 */
   2696 		return (0);
   2697 	}
   2698 	for (i = 0; i < p->dlt_count; i++)
   2699 		if (p->dlt_list[i] == (u_int)dlt)
   2700 			break;
   2701 	if (i >= p->dlt_count)
   2702 		goto unsupported;
   2703 	if (p->dlt_count == 2 && p->dlt_list[0] == DLT_EN10MB &&
   2704 	    dlt == DLT_DOCSIS) {
   2705 		/*
   2706 		 * This is presumably an Ethernet device, as the first
   2707 		 * link-layer type it offers is DLT_EN10MB, and the only
   2708 		 * other type it offers is DLT_DOCSIS.  That means that
   2709 		 * we can't tell the driver to supply DOCSIS link-layer
   2710 		 * headers - we're just pretending that's what we're
   2711 		 * getting, as, presumably, we're capturing on a dedicated
   2712 		 * link to a Cisco Cable Modem Termination System, and
   2713 		 * it's putting raw DOCSIS frames on the wire inside low-level
   2714 		 * Ethernet framing.
   2715 		 */
   2716 		p->linktype = dlt;
   2717 		return (0);
   2718 	}
   2719 	if (p->set_datalink_op(p, dlt) == -1)
   2720 		return (-1);
   2721 	p->linktype = dlt;
   2722 	return (0);
   2723 
   2724 unsupported:
   2725 	dlt_name = pcap_datalink_val_to_name(dlt);
   2726 	if (dlt_name != NULL) {
   2727 		(void) pcap_snprintf(p->errbuf, sizeof(p->errbuf),
   2728 		    "%s is not one of the DLTs supported by this device",
   2729 		    dlt_name);
   2730 	} else {
   2731 		(void) pcap_snprintf(p->errbuf, sizeof(p->errbuf),
   2732 		    "DLT %d is not one of the DLTs supported by this device",
   2733 		    dlt);
   2734 	}
   2735 	return (-1);
   2736 }
   2737 
   2738 /*
   2739  * This array is designed for mapping upper and lower case letter
   2740  * together for a case independent comparison.  The mappings are
   2741  * based upon ascii character sequences.
   2742  */
   2743 static const u_char charmap[] = {
   2744 	(u_char)'\000', (u_char)'\001', (u_char)'\002', (u_char)'\003',
   2745 	(u_char)'\004', (u_char)'\005', (u_char)'\006', (u_char)'\007',
   2746 	(u_char)'\010', (u_char)'\011', (u_char)'\012', (u_char)'\013',
   2747 	(u_char)'\014', (u_char)'\015', (u_char)'\016', (u_char)'\017',
   2748 	(u_char)'\020', (u_char)'\021', (u_char)'\022', (u_char)'\023',
   2749 	(u_char)'\024', (u_char)'\025', (u_char)'\026', (u_char)'\027',
   2750 	(u_char)'\030', (u_char)'\031', (u_char)'\032', (u_char)'\033',
   2751 	(u_char)'\034', (u_char)'\035', (u_char)'\036', (u_char)'\037',
   2752 	(u_char)'\040', (u_char)'\041', (u_char)'\042', (u_char)'\043',
   2753 	(u_char)'\044', (u_char)'\045', (u_char)'\046', (u_char)'\047',
   2754 	(u_char)'\050', (u_char)'\051', (u_char)'\052', (u_char)'\053',
   2755 	(u_char)'\054', (u_char)'\055', (u_char)'\056', (u_char)'\057',
   2756 	(u_char)'\060', (u_char)'\061', (u_char)'\062', (u_char)'\063',
   2757 	(u_char)'\064', (u_char)'\065', (u_char)'\066', (u_char)'\067',
   2758 	(u_char)'\070', (u_char)'\071', (u_char)'\072', (u_char)'\073',
   2759 	(u_char)'\074', (u_char)'\075', (u_char)'\076', (u_char)'\077',
   2760 	(u_char)'\100', (u_char)'\141', (u_char)'\142', (u_char)'\143',
   2761 	(u_char)'\144', (u_char)'\145', (u_char)'\146', (u_char)'\147',
   2762 	(u_char)'\150', (u_char)'\151', (u_char)'\152', (u_char)'\153',
   2763 	(u_char)'\154', (u_char)'\155', (u_char)'\156', (u_char)'\157',
   2764 	(u_char)'\160', (u_char)'\161', (u_char)'\162', (u_char)'\163',
   2765 	(u_char)'\164', (u_char)'\165', (u_char)'\166', (u_char)'\167',
   2766 	(u_char)'\170', (u_char)'\171', (u_char)'\172', (u_char)'\133',
   2767 	(u_char)'\134', (u_char)'\135', (u_char)'\136', (u_char)'\137',
   2768 	(u_char)'\140', (u_char)'\141', (u_char)'\142', (u_char)'\143',
   2769 	(u_char)'\144', (u_char)'\145', (u_char)'\146', (u_char)'\147',
   2770 	(u_char)'\150', (u_char)'\151', (u_char)'\152', (u_char)'\153',
   2771 	(u_char)'\154', (u_char)'\155', (u_char)'\156', (u_char)'\157',
   2772 	(u_char)'\160', (u_char)'\161', (u_char)'\162', (u_char)'\163',
   2773 	(u_char)'\164', (u_char)'\165', (u_char)'\166', (u_char)'\167',
   2774 	(u_char)'\170', (u_char)'\171', (u_char)'\172', (u_char)'\173',
   2775 	(u_char)'\174', (u_char)'\175', (u_char)'\176', (u_char)'\177',
   2776 	(u_char)'\200', (u_char)'\201', (u_char)'\202', (u_char)'\203',
   2777 	(u_char)'\204', (u_char)'\205', (u_char)'\206', (u_char)'\207',
   2778 	(u_char)'\210', (u_char)'\211', (u_char)'\212', (u_char)'\213',
   2779 	(u_char)'\214', (u_char)'\215', (u_char)'\216', (u_char)'\217',
   2780 	(u_char)'\220', (u_char)'\221', (u_char)'\222', (u_char)'\223',
   2781 	(u_char)'\224', (u_char)'\225', (u_char)'\226', (u_char)'\227',
   2782 	(u_char)'\230', (u_char)'\231', (u_char)'\232', (u_char)'\233',
   2783 	(u_char)'\234', (u_char)'\235', (u_char)'\236', (u_char)'\237',
   2784 	(u_char)'\240', (u_char)'\241', (u_char)'\242', (u_char)'\243',
   2785 	(u_char)'\244', (u_char)'\245', (u_char)'\246', (u_char)'\247',
   2786 	(u_char)'\250', (u_char)'\251', (u_char)'\252', (u_char)'\253',
   2787 	(u_char)'\254', (u_char)'\255', (u_char)'\256', (u_char)'\257',
   2788 	(u_char)'\260', (u_char)'\261', (u_char)'\262', (u_char)'\263',
   2789 	(u_char)'\264', (u_char)'\265', (u_char)'\266', (u_char)'\267',
   2790 	(u_char)'\270', (u_char)'\271', (u_char)'\272', (u_char)'\273',
   2791 	(u_char)'\274', (u_char)'\275', (u_char)'\276', (u_char)'\277',
   2792 	(u_char)'\300', (u_char)'\341', (u_char)'\342', (u_char)'\343',
   2793 	(u_char)'\344', (u_char)'\345', (u_char)'\346', (u_char)'\347',
   2794 	(u_char)'\350', (u_char)'\351', (u_char)'\352', (u_char)'\353',
   2795 	(u_char)'\354', (u_char)'\355', (u_char)'\356', (u_char)'\357',
   2796 	(u_char)'\360', (u_char)'\361', (u_char)'\362', (u_char)'\363',
   2797 	(u_char)'\364', (u_char)'\365', (u_char)'\366', (u_char)'\367',
   2798 	(u_char)'\370', (u_char)'\371', (u_char)'\372', (u_char)'\333',
   2799 	(u_char)'\334', (u_char)'\335', (u_char)'\336', (u_char)'\337',
   2800 	(u_char)'\340', (u_char)'\341', (u_char)'\342', (u_char)'\343',
   2801 	(u_char)'\344', (u_char)'\345', (u_char)'\346', (u_char)'\347',
   2802 	(u_char)'\350', (u_char)'\351', (u_char)'\352', (u_char)'\353',
   2803 	(u_char)'\354', (u_char)'\355', (u_char)'\356', (u_char)'\357',
   2804 	(u_char)'\360', (u_char)'\361', (u_char)'\362', (u_char)'\363',
   2805 	(u_char)'\364', (u_char)'\365', (u_char)'\366', (u_char)'\367',
   2806 	(u_char)'\370', (u_char)'\371', (u_char)'\372', (u_char)'\373',
   2807 	(u_char)'\374', (u_char)'\375', (u_char)'\376', (u_char)'\377',
   2808 };
   2809 
   2810 int
   2811 pcap_strcasecmp(const char *s1, const char *s2)
   2812 {
   2813 	register const u_char	*cm = charmap,
   2814 				*us1 = (const u_char *)s1,
   2815 				*us2 = (const u_char *)s2;
   2816 
   2817 	while (cm[*us1] == cm[*us2++])
   2818 		if (*us1++ == '\0')
   2819 			return(0);
   2820 	return (cm[*us1] - cm[*--us2]);
   2821 }
   2822 
   2823 struct dlt_choice {
   2824 	const char *name;
   2825 	const char *description;
   2826 	int	dlt;
   2827 };
   2828 
   2829 #define DLT_CHOICE(code, description) { #code, description, DLT_ ## code }
   2830 #define DLT_CHOICE_SENTINEL { NULL, NULL, 0 }
   2831 
   2832 static struct dlt_choice dlt_choices[] = {
   2833 	DLT_CHOICE(NULL, "BSD loopback"),
   2834 	DLT_CHOICE(EN10MB, "Ethernet"),
   2835 	DLT_CHOICE(IEEE802, "Token ring"),
   2836 	DLT_CHOICE(ARCNET, "BSD ARCNET"),
   2837 	DLT_CHOICE(SLIP, "SLIP"),
   2838 	DLT_CHOICE(PPP, "PPP"),
   2839 	DLT_CHOICE(FDDI, "FDDI"),
   2840 	DLT_CHOICE(ATM_RFC1483, "RFC 1483 LLC-encapsulated ATM"),
   2841 	DLT_CHOICE(RAW, "Raw IP"),
   2842 	DLT_CHOICE(SLIP_BSDOS, "BSD/OS SLIP"),
   2843 	DLT_CHOICE(PPP_BSDOS, "BSD/OS PPP"),
   2844 	DLT_CHOICE(ATM_CLIP, "Linux Classical IP-over-ATM"),
   2845 	DLT_CHOICE(PPP_SERIAL, "PPP over serial"),
   2846 	DLT_CHOICE(PPP_ETHER, "PPPoE"),
   2847 	DLT_CHOICE(SYMANTEC_FIREWALL, "Symantec Firewall"),
   2848 	DLT_CHOICE(C_HDLC, "Cisco HDLC"),
   2849 	DLT_CHOICE(IEEE802_11, "802.11"),
   2850 	DLT_CHOICE(FRELAY, "Frame Relay"),
   2851 	DLT_CHOICE(LOOP, "OpenBSD loopback"),
   2852 	DLT_CHOICE(ENC, "OpenBSD encapsulated IP"),
   2853 	DLT_CHOICE(LINUX_SLL, "Linux cooked"),
   2854 	DLT_CHOICE(LTALK, "Localtalk"),
   2855 	DLT_CHOICE(PFLOG, "OpenBSD pflog file"),
   2856 	DLT_CHOICE(PFSYNC, "Packet filter state syncing"),
   2857 	DLT_CHOICE(PRISM_HEADER, "802.11 plus Prism header"),
   2858 	DLT_CHOICE(IP_OVER_FC, "RFC 2625 IP-over-Fibre Channel"),
   2859 	DLT_CHOICE(SUNATM, "Sun raw ATM"),
   2860 	DLT_CHOICE(IEEE802_11_RADIO, "802.11 plus radiotap header"),
   2861 	DLT_CHOICE(ARCNET_LINUX, "Linux ARCNET"),
   2862 	DLT_CHOICE(JUNIPER_MLPPP, "Juniper Multi-Link PPP"),
   2863 	DLT_CHOICE(JUNIPER_MLFR, "Juniper Multi-Link Frame Relay"),
   2864 	DLT_CHOICE(JUNIPER_ES, "Juniper Encryption Services PIC"),
   2865 	DLT_CHOICE(JUNIPER_GGSN, "Juniper GGSN PIC"),
   2866 	DLT_CHOICE(JUNIPER_MFR, "Juniper FRF.16 Frame Relay"),
   2867 	DLT_CHOICE(JUNIPER_ATM2, "Juniper ATM2 PIC"),
   2868 	DLT_CHOICE(JUNIPER_SERVICES, "Juniper Advanced Services PIC"),
   2869 	DLT_CHOICE(JUNIPER_ATM1, "Juniper ATM1 PIC"),
   2870 	DLT_CHOICE(APPLE_IP_OVER_IEEE1394, "Apple IP-over-IEEE 1394"),
   2871 	DLT_CHOICE(MTP2_WITH_PHDR, "SS7 MTP2 with Pseudo-header"),
   2872 	DLT_CHOICE(MTP2, "SS7 MTP2"),
   2873 	DLT_CHOICE(MTP3, "SS7 MTP3"),
   2874 	DLT_CHOICE(SCCP, "SS7 SCCP"),
   2875 	DLT_CHOICE(DOCSIS, "DOCSIS"),
   2876 	DLT_CHOICE(LINUX_IRDA, "Linux IrDA"),
   2877 	DLT_CHOICE(IEEE802_11_RADIO_AVS, "802.11 plus AVS radio information header"),
   2878 	DLT_CHOICE(JUNIPER_MONITOR, "Juniper Passive Monitor PIC"),
   2879 	DLT_CHOICE(BACNET_MS_TP, "BACnet MS/TP"),
   2880 	DLT_CHOICE(PPP_PPPD, "PPP for pppd, with direction flag"),
   2881 	DLT_CHOICE(JUNIPER_PPPOE, "Juniper PPPoE"),
   2882 	DLT_CHOICE(JUNIPER_PPPOE_ATM, "Juniper PPPoE/ATM"),
   2883 	DLT_CHOICE(GPRS_LLC, "GPRS LLC"),
   2884 	DLT_CHOICE(GPF_T, "GPF-T"),
   2885 	DLT_CHOICE(GPF_F, "GPF-F"),
   2886 	DLT_CHOICE(JUNIPER_PIC_PEER, "Juniper PIC Peer"),
   2887 	DLT_CHOICE(ERF_ETH,	"Ethernet with Endace ERF header"),
   2888 	DLT_CHOICE(ERF_POS, "Packet-over-SONET with Endace ERF header"),
   2889 	DLT_CHOICE(LINUX_LAPD, "Linux vISDN LAPD"),
   2890 	DLT_CHOICE(JUNIPER_ETHER, "Juniper Ethernet"),
   2891 	DLT_CHOICE(JUNIPER_PPP, "Juniper PPP"),
   2892 	DLT_CHOICE(JUNIPER_FRELAY, "Juniper Frame Relay"),
   2893 	DLT_CHOICE(JUNIPER_CHDLC, "Juniper C-HDLC"),
   2894 	DLT_CHOICE(MFR, "FRF.16 Frame Relay"),
   2895 	DLT_CHOICE(JUNIPER_VP, "Juniper Voice PIC"),
   2896 	DLT_CHOICE(A429, "Arinc 429"),
   2897 	DLT_CHOICE(A653_ICM, "Arinc 653 Interpartition Communication"),
   2898 	DLT_CHOICE(USB_FREEBSD, "USB with FreeBSD header"),
   2899 	DLT_CHOICE(BLUETOOTH_HCI_H4, "Bluetooth HCI UART transport layer"),
   2900 	DLT_CHOICE(IEEE802_16_MAC_CPS, "IEEE 802.16 MAC Common Part Sublayer"),
   2901 	DLT_CHOICE(USB_LINUX, "USB with Linux header"),
   2902 	DLT_CHOICE(CAN20B, "Controller Area Network (CAN) v. 2.0B"),
   2903 	DLT_CHOICE(IEEE802_15_4_LINUX, "IEEE 802.15.4 with Linux padding"),
   2904 	DLT_CHOICE(PPI, "Per-Packet Information"),
   2905 	DLT_CHOICE(IEEE802_16_MAC_CPS_RADIO, "IEEE 802.16 MAC Common Part Sublayer plus radiotap header"),
   2906 	DLT_CHOICE(JUNIPER_ISM, "Juniper Integrated Service Module"),
   2907 	DLT_CHOICE(IEEE802_15_4, "IEEE 802.15.4 with FCS"),
   2908 	DLT_CHOICE(SITA, "SITA pseudo-header"),
   2909 	DLT_CHOICE(ERF, "Endace ERF header"),
   2910 	DLT_CHOICE(RAIF1, "Ethernet with u10 Networks pseudo-header"),
   2911 	DLT_CHOICE(IPMB, "IPMB"),
   2912 	DLT_CHOICE(JUNIPER_ST, "Juniper Secure Tunnel"),
   2913 	DLT_CHOICE(BLUETOOTH_HCI_H4_WITH_PHDR, "Bluetooth HCI UART transport layer plus pseudo-header"),
   2914 	DLT_CHOICE(AX25_KISS, "AX.25 with KISS header"),
   2915 	DLT_CHOICE(IEEE802_15_4_NONASK_PHY, "IEEE 802.15.4 with non-ASK PHY data"),
   2916 	DLT_CHOICE(MPLS, "MPLS with label as link-layer header"),
   2917 	DLT_CHOICE(LINUX_EVDEV, "Linux evdev events"),
   2918 	DLT_CHOICE(USB_LINUX_MMAPPED, "USB with padded Linux header"),
   2919 	DLT_CHOICE(DECT, "DECT"),
   2920 	DLT_CHOICE(AOS, "AOS Space Data Link protocol"),
   2921 	DLT_CHOICE(WIHART, "Wireless HART"),
   2922 	DLT_CHOICE(FC_2, "Fibre Channel FC-2"),
   2923 	DLT_CHOICE(FC_2_WITH_FRAME_DELIMS, "Fibre Channel FC-2 with frame delimiters"),
   2924 	DLT_CHOICE(IPNET, "Solaris ipnet"),
   2925 	DLT_CHOICE(CAN_SOCKETCAN, "CAN-bus with SocketCAN headers"),
   2926 	DLT_CHOICE(IPV4, "Raw IPv4"),
   2927 	DLT_CHOICE(IPV6, "Raw IPv6"),
   2928 	DLT_CHOICE(IEEE802_15_4_NOFCS, "IEEE 802.15.4 without FCS"),
   2929 	DLT_CHOICE(DBUS, "D-Bus"),
   2930 	DLT_CHOICE(JUNIPER_VS, "Juniper Virtual Server"),
   2931 	DLT_CHOICE(JUNIPER_SRX_E2E, "Juniper SRX E2E"),
   2932 	DLT_CHOICE(JUNIPER_FIBRECHANNEL, "Juniper Fibre Channel"),
   2933 	DLT_CHOICE(DVB_CI, "DVB-CI"),
   2934 	DLT_CHOICE(MUX27010, "MUX27010"),
   2935 	DLT_CHOICE(STANAG_5066_D_PDU, "STANAG 5066 D_PDUs"),
   2936 	DLT_CHOICE(JUNIPER_ATM_CEMIC, "Juniper ATM CEMIC"),
   2937 	DLT_CHOICE(NFLOG, "Linux netfilter log messages"),
   2938 	DLT_CHOICE(NETANALYZER, "Ethernet with Hilscher netANALYZER pseudo-header"),
   2939 	DLT_CHOICE(NETANALYZER_TRANSPARENT, "Ethernet with Hilscher netANALYZER pseudo-header and with preamble and SFD"),
   2940 	DLT_CHOICE(IPOIB, "RFC 4391 IP-over-Infiniband"),
   2941 	DLT_CHOICE(MPEG_2_TS, "MPEG-2 transport stream"),
   2942 	DLT_CHOICE(NG40, "ng40 protocol tester Iub/Iur"),
   2943 	DLT_CHOICE(NFC_LLCP, "NFC LLCP PDUs with pseudo-header"),
   2944 	DLT_CHOICE(INFINIBAND, "InfiniBand"),
   2945 	DLT_CHOICE(SCTP, "SCTP"),
   2946 	DLT_CHOICE(USBPCAP, "USB with USBPcap header"),
   2947 	DLT_CHOICE(RTAC_SERIAL, "Schweitzer Engineering Laboratories RTAC packets"),
   2948 	DLT_CHOICE(BLUETOOTH_LE_LL, "Bluetooth Low Energy air interface"),
   2949 	DLT_CHOICE(NETLINK, "Linux netlink"),
   2950 	DLT_CHOICE(BLUETOOTH_LINUX_MONITOR, "Bluetooth Linux Monitor"),
   2951 	DLT_CHOICE(BLUETOOTH_BREDR_BB, "Bluetooth Basic Rate/Enhanced Data Rate baseband packets"),
   2952 	DLT_CHOICE(BLUETOOTH_LE_LL_WITH_PHDR, "Bluetooth Low Energy air interface with pseudo-header"),
   2953 	DLT_CHOICE(PROFIBUS_DL, "PROFIBUS data link layer"),
   2954 	DLT_CHOICE(PKTAP, "Apple DLT_PKTAP"),
   2955 	DLT_CHOICE(EPON, "Ethernet with 802.3 Clause 65 EPON preamble"),
   2956 	DLT_CHOICE(IPMI_HPM_2, "IPMI trace packets"),
   2957 	DLT_CHOICE(ZWAVE_R1_R2, "Z-Wave RF profile R1 and R2 packets"),
   2958 	DLT_CHOICE(ZWAVE_R3, "Z-Wave RF profile R3 packets"),
   2959 	DLT_CHOICE(WATTSTOPPER_DLM, "WattStopper Digital Lighting Management (DLM) and Legrand Nitoo Open protocol"),
   2960 	DLT_CHOICE(ISO_14443, "ISO 14443 messages"),
   2961 	DLT_CHOICE(RDS, "IEC 62106 Radio Data System groups"),
   2962 	DLT_CHOICE(USB_DARWIN, "USB with Darwin header"),
   2963 	DLT_CHOICE(OPENFLOW, "OpenBSD DLT_OPENFLOW"),
   2964 	DLT_CHOICE(SDLC, "IBM SDLC frames"),
   2965 	DLT_CHOICE(TI_LLN_SNIFFER, "TI LLN sniffer frames"),
   2966 	DLT_CHOICE(VSOCK, "Linux vsock"),
   2967 	DLT_CHOICE(NORDIC_BLE, "Nordic Semiconductor Bluetooth LE sniffer frames"),
   2968 	DLT_CHOICE(DOCSIS31_XRA31, "Excentis XRA-31 DOCSIS 3.1 RF sniffer frames"),
   2969 	DLT_CHOICE(ETHERNET_MPACKET, "802.3br mPackets"),
   2970 	DLT_CHOICE(DISPLAYPORT_AUX, "DisplayPort AUX channel monitoring data"),
   2971 	DLT_CHOICE_SENTINEL
   2972 };
   2973 
   2974 int
   2975 pcap_datalink_name_to_val(const char *name)
   2976 {
   2977 	int i;
   2978 
   2979 	for (i = 0; dlt_choices[i].name != NULL; i++) {
   2980 		if (pcap_strcasecmp(dlt_choices[i].name, name) == 0)
   2981 			return (dlt_choices[i].dlt);
   2982 	}
   2983 	return (-1);
   2984 }
   2985 
   2986 const char *
   2987 pcap_datalink_val_to_name(int dlt)
   2988 {
   2989 	int i;
   2990 
   2991 	for (i = 0; dlt_choices[i].name != NULL; i++) {
   2992 		if (dlt_choices[i].dlt == dlt)
   2993 			return (dlt_choices[i].name);
   2994 	}
   2995 	return (NULL);
   2996 }
   2997 
   2998 const char *
   2999 pcap_datalink_val_to_description(int dlt)
   3000 {
   3001 	int i;
   3002 
   3003 	for (i = 0; dlt_choices[i].name != NULL; i++) {
   3004 		if (dlt_choices[i].dlt == dlt)
   3005 			return (dlt_choices[i].description);
   3006 	}
   3007 	return (NULL);
   3008 }
   3009 
   3010 struct tstamp_type_choice {
   3011 	const char *name;
   3012 	const char *description;
   3013 	int	type;
   3014 };
   3015 
   3016 static struct tstamp_type_choice tstamp_type_choices[] = {
   3017 	{ "host", "Host", PCAP_TSTAMP_HOST },
   3018 	{ "host_lowprec", "Host, low precision", PCAP_TSTAMP_HOST_LOWPREC },
   3019 	{ "host_hiprec", "Host, high precision", PCAP_TSTAMP_HOST_HIPREC },
   3020 	{ "adapter", "Adapter", PCAP_TSTAMP_ADAPTER },
   3021 	{ "adapter_unsynced", "Adapter, not synced with system time", PCAP_TSTAMP_ADAPTER_UNSYNCED },
   3022 	{ NULL, NULL, 0 }
   3023 };
   3024 
   3025 int
   3026 pcap_tstamp_type_name_to_val(const char *name)
   3027 {
   3028 	int i;
   3029 
   3030 	for (i = 0; tstamp_type_choices[i].name != NULL; i++) {
   3031 		if (pcap_strcasecmp(tstamp_type_choices[i].name, name) == 0)
   3032 			return (tstamp_type_choices[i].type);
   3033 	}
   3034 	return (PCAP_ERROR);
   3035 }
   3036 
   3037 const char *
   3038 pcap_tstamp_type_val_to_name(int tstamp_type)
   3039 {
   3040 	int i;
   3041 
   3042 	for (i = 0; tstamp_type_choices[i].name != NULL; i++) {
   3043 		if (tstamp_type_choices[i].type == tstamp_type)
   3044 			return (tstamp_type_choices[i].name);
   3045 	}
   3046 	return (NULL);
   3047 }
   3048 
   3049 const char *
   3050 pcap_tstamp_type_val_to_description(int tstamp_type)
   3051 {
   3052 	int i;
   3053 
   3054 	for (i = 0; tstamp_type_choices[i].name != NULL; i++) {
   3055 		if (tstamp_type_choices[i].type == tstamp_type)
   3056 			return (tstamp_type_choices[i].description);
   3057 	}
   3058 	return (NULL);
   3059 }
   3060 
   3061 int
   3062 pcap_snapshot(pcap_t *p)
   3063 {
   3064 	if (!p->activated)
   3065 		return (PCAP_ERROR_NOT_ACTIVATED);
   3066 	return (p->snapshot);
   3067 }
   3068 
   3069 int
   3070 pcap_is_swapped(pcap_t *p)
   3071 {
   3072 	if (!p->activated)
   3073 		return (PCAP_ERROR_NOT_ACTIVATED);
   3074 	return (p->swapped);
   3075 }
   3076 
   3077 int
   3078 pcap_major_version(pcap_t *p)
   3079 {
   3080 	if (!p->activated)
   3081 		return (PCAP_ERROR_NOT_ACTIVATED);
   3082 	return (p->version_major);
   3083 }
   3084 
   3085 int
   3086 pcap_minor_version(pcap_t *p)
   3087 {
   3088 	if (!p->activated)
   3089 		return (PCAP_ERROR_NOT_ACTIVATED);
   3090 	return (p->version_minor);
   3091 }
   3092 
   3093 int
   3094 pcap_bufsize(pcap_t *p)
   3095 {
   3096 	if (!p->activated)
   3097 		return (PCAP_ERROR_NOT_ACTIVATED);
   3098 	return (p->bufsize);
   3099 }
   3100 
   3101 FILE *
   3102 pcap_file(pcap_t *p)
   3103 {
   3104 	return (p->rfile);
   3105 }
   3106 
   3107 int
   3108 pcap_fileno(pcap_t *p)
   3109 {
   3110 #ifndef _WIN32
   3111 	return (p->fd);
   3112 #else
   3113 	if (p->handle != INVALID_HANDLE_VALUE)
   3114 		return ((int)(DWORD)p->handle);
   3115 	else
   3116 		return (PCAP_ERROR);
   3117 #endif
   3118 }
   3119 
   3120 #if !defined(_WIN32) && !defined(MSDOS)
   3121 int
   3122 pcap_get_selectable_fd(pcap_t *p)
   3123 {
   3124 	return (p->selectable_fd);
   3125 }
   3126 
   3127 struct timeval *
   3128 pcap_get_required_select_timeout(pcap_t *p)
   3129 {
   3130 	return (p->required_select_timeout);
   3131 }
   3132 #endif
   3133 
   3134 void
   3135 pcap_perror(pcap_t *p, const char *prefix)
   3136 {
   3137 	fprintf(stderr, "%s: %s\n", prefix, p->errbuf);
   3138 }
   3139 
   3140 char *
   3141 pcap_geterr(pcap_t *p)
   3142 {
   3143 	return (p->errbuf);
   3144 }
   3145 
   3146 int
   3147 pcap_getnonblock(pcap_t *p, char *errbuf)
   3148 {
   3149 	int ret;
   3150 
   3151 	ret = p->getnonblock_op(p);
   3152 	if (ret == -1) {
   3153 		/*
   3154 		 * The get nonblock operation sets p->errbuf; this
   3155 		 * function *shouldn't* have had a separate errbuf
   3156 		 * argument, as it didn't need one, but I goofed
   3157 		 * when adding it.
   3158 		 *
   3159 		 * We copy the error message to errbuf, so callers
   3160 		 * can find it in either place.
   3161 		 */
   3162 		strlcpy(errbuf, p->errbuf, PCAP_ERRBUF_SIZE);
   3163 	}
   3164 	return (ret);
   3165 }
   3166 
   3167 /*
   3168  * Get the current non-blocking mode setting, under the assumption that
   3169  * it's just the standard POSIX non-blocking flag.
   3170  */
   3171 #if !defined(_WIN32) && !defined(MSDOS)
   3172 int
   3173 pcap_getnonblock_fd(pcap_t *p)
   3174 {
   3175 	int fdflags;
   3176 
   3177 	fdflags = fcntl(p->fd, F_GETFL, 0);
   3178 	if (fdflags == -1) {
   3179 		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
   3180 		    errno, "F_GETFL");
   3181 		return (-1);
   3182 	}
   3183 	if (fdflags & O_NONBLOCK)
   3184 		return (1);
   3185 	else
   3186 		return (0);
   3187 }
   3188 #endif
   3189 
   3190 int
   3191 pcap_setnonblock(pcap_t *p, int nonblock, char *errbuf)
   3192 {
   3193 	int ret;
   3194 
   3195 	ret = p->setnonblock_op(p, nonblock);
   3196 	if (ret == -1) {
   3197 		/*
   3198 		 * The set nonblock operation sets p->errbuf; this
   3199 		 * function *shouldn't* have had a separate errbuf
   3200 		 * argument, as it didn't need one, but I goofed
   3201 		 * when adding it.
   3202 		 *
   3203 		 * We copy the error message to errbuf, so callers
   3204 		 * can find it in either place.
   3205 		 */
   3206 		strlcpy(errbuf, p->errbuf, PCAP_ERRBUF_SIZE);
   3207 	}
   3208 	return (ret);
   3209 }
   3210 
   3211 #if !defined(_WIN32) && !defined(MSDOS)
   3212 /*
   3213  * Set non-blocking mode, under the assumption that it's just the
   3214  * standard POSIX non-blocking flag.  (This can be called by the
   3215  * per-platform non-blocking-mode routine if that routine also
   3216  * needs to do some additional work.)
   3217  */
   3218 int
   3219 pcap_setnonblock_fd(pcap_t *p, int nonblock)
   3220 {
   3221 	int fdflags;
   3222 
   3223 	fdflags = fcntl(p->fd, F_GETFL, 0);
   3224 	if (fdflags == -1) {
   3225 		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
   3226 		    errno, "F_GETFL");
   3227 		return (-1);
   3228 	}
   3229 	if (nonblock)
   3230 		fdflags |= O_NONBLOCK;
   3231 	else
   3232 		fdflags &= ~O_NONBLOCK;
   3233 	if (fcntl(p->fd, F_SETFL, fdflags) == -1) {
   3234 		pcap_fmt_errmsg_for_errno(p->errbuf, PCAP_ERRBUF_SIZE,
   3235 		    errno, "F_SETFL");
   3236 		return (-1);
   3237 	}
   3238 	return (0);
   3239 }
   3240 #endif
   3241 
   3242 #ifdef _WIN32
   3243 /*
   3244  * Generate a string for a Win32-specific error (i.e. an error generated when
   3245  * calling a Win32 API).
   3246  * For errors occurred during standard C calls, we still use pcap_strerror()
   3247  */
   3248 void
   3249 pcap_win32_err_to_str(DWORD error, char *errbuf)
   3250 {
   3251 	size_t errlen;
   3252 	char *p;
   3253 
   3254 	FormatMessageA(FORMAT_MESSAGE_FROM_SYSTEM, NULL, error, 0, errbuf,
   3255 	    PCAP_ERRBUF_SIZE, NULL);
   3256 
   3257 	/*
   3258 	 * "FormatMessage()" "helpfully" sticks CR/LF at the end of the
   3259 	 * message.  Get rid of it.
   3260 	 */
   3261 	errlen = strlen(errbuf);
   3262 	if (errlen >= 2) {
   3263 		errbuf[errlen - 1] = '\0';
   3264 		errbuf[errlen - 2] = '\0';
   3265 	}
   3266 	p = strchr(errbuf, '\0');
   3267 	pcap_snprintf (p, PCAP_ERRBUF_SIZE+1-(p-errbuf), " (%lu)", error);
   3268 }
   3269 #endif
   3270 
   3271 /*
   3272  * Generate error strings for PCAP_ERROR_ and PCAP_WARNING_ values.
   3273  */
   3274 const char *
   3275 pcap_statustostr(int errnum)
   3276 {
   3277 	static char ebuf[15+10+1];
   3278 
   3279 	switch (errnum) {
   3280 
   3281 	case PCAP_WARNING:
   3282 		return("Generic warning");
   3283 
   3284 	case PCAP_WARNING_TSTAMP_TYPE_NOTSUP:
   3285 		return ("That type of time stamp is not supported by that device");
   3286 
   3287 	case PCAP_WARNING_PROMISC_NOTSUP:
   3288 		return ("That device doesn't support promiscuous mode");
   3289 
   3290 	case PCAP_ERROR:
   3291 		return("Generic error");
   3292 
   3293 	case PCAP_ERROR_BREAK:
   3294 		return("Loop terminated by pcap_breakloop");
   3295 
   3296 	case PCAP_ERROR_NOT_ACTIVATED:
   3297 		return("The pcap_t has not been activated");
   3298 
   3299 	case PCAP_ERROR_ACTIVATED:
   3300 		return ("The setting can't be changed after the pcap_t is activated");
   3301 
   3302 	case PCAP_ERROR_NO_SUCH_DEVICE:
   3303 		return ("No such device exists");
   3304 
   3305 	case PCAP_ERROR_RFMON_NOTSUP:
   3306 		return ("That device doesn't support monitor mode");
   3307 
   3308 	case PCAP_ERROR_NOT_RFMON:
   3309 		return ("That operation is supported only in monitor mode");
   3310 
   3311 	case PCAP_ERROR_PERM_DENIED:
   3312 		return ("You don't have permission to capture on that device");
   3313 
   3314 	case PCAP_ERROR_IFACE_NOT_UP:
   3315 		return ("That device is not up");
   3316 
   3317 	case PCAP_ERROR_CANTSET_TSTAMP_TYPE:
   3318 		return ("That device doesn't support setting the time stamp type");
   3319 
   3320 	case PCAP_ERROR_PROMISC_PERM_DENIED:
   3321 		return ("You don't have permission to capture in promiscuous mode on that device");
   3322 
   3323 	case PCAP_ERROR_TSTAMP_PRECISION_NOTSUP:
   3324 		return ("That device doesn't support that time stamp precision");
   3325 	}
   3326 	(void)pcap_snprintf(ebuf, sizeof ebuf, "Unknown error: %d", errnum);
   3327 	return(ebuf);
   3328 }
   3329 
   3330 /*
   3331  * Not all systems have strerror().
   3332  */
   3333 const char *
   3334 pcap_strerror(int errnum)
   3335 {
   3336 #ifdef HAVE_STRERROR
   3337 #ifdef _WIN32
   3338 	static char errbuf[PCAP_ERRBUF_SIZE];
   3339 	errno_t err = strerror_s(errbuf, PCAP_ERRBUF_SIZE, errnum);
   3340 
   3341 	if (err != 0) /* err = 0 if successful */
   3342 		strlcpy(errbuf, "strerror_s() error", PCAP_ERRBUF_SIZE);
   3343 	return (errbuf);
   3344 #else
   3345 	return (strerror(errnum));
   3346 #endif /* _WIN32 */
   3347 #else
   3348 	extern int sys_nerr;
   3349 	extern const char *const sys_errlist[];
   3350 	static char errbuf[PCAP_ERRBUF_SIZE];
   3351 
   3352 	if ((unsigned int)errnum < sys_nerr)
   3353 		return ((char *)sys_errlist[errnum]);
   3354 	(void)pcap_snprintf(errbuf, sizeof errbuf, "Unknown error: %d", errnum);
   3355 	return (errbuf);
   3356 #endif
   3357 }
   3358 
   3359 int
   3360 pcap_setfilter(pcap_t *p, struct bpf_program *fp)
   3361 {
   3362 	return (p->setfilter_op(p, fp));
   3363 }
   3364 
   3365 /*
   3366  * Set direction flag, which controls whether we accept only incoming
   3367  * packets, only outgoing packets, or both.
   3368  * Note that, depending on the platform, some or all direction arguments
   3369  * might not be supported.
   3370  */
   3371 int
   3372 pcap_setdirection(pcap_t *p, pcap_direction_t d)
   3373 {
   3374 	if (p->setdirection_op == NULL) {
   3375 		pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
   3376 		    "Setting direction is not implemented on this platform");
   3377 		return (-1);
   3378 	} else
   3379 		return (p->setdirection_op(p, d));
   3380 }
   3381 
   3382 int
   3383 pcap_stats(pcap_t *p, struct pcap_stat *ps)
   3384 {
   3385 	return (p->stats_op(p, ps));
   3386 }
   3387 
   3388 #ifdef _WIN32
   3389 struct pcap_stat *
   3390 pcap_stats_ex(pcap_t *p, int *pcap_stat_size)
   3391 {
   3392 	return (p->stats_ex_op(p, pcap_stat_size));
   3393 }
   3394 
   3395 int
   3396 pcap_setbuff(pcap_t *p, int dim)
   3397 {
   3398 	return (p->setbuff_op(p, dim));
   3399 }
   3400 
   3401 int
   3402 pcap_setmode(pcap_t *p, int mode)
   3403 {
   3404 	return (p->setmode_op(p, mode));
   3405 }
   3406 
   3407 int
   3408 pcap_setmintocopy(pcap_t *p, int size)
   3409 {
   3410 	return (p->setmintocopy_op(p, size));
   3411 }
   3412 
   3413 HANDLE
   3414 pcap_getevent(pcap_t *p)
   3415 {
   3416 	return (p->getevent_op(p));
   3417 }
   3418 
   3419 int
   3420 pcap_oid_get_request(pcap_t *p, bpf_u_int32 oid, void *data, size_t *lenp)
   3421 {
   3422 	return (p->oid_get_request_op(p, oid, data, lenp));
   3423 }
   3424 
   3425 int
   3426 pcap_oid_set_request(pcap_t *p, bpf_u_int32 oid, const void *data, size_t *lenp)
   3427 {
   3428 	return (p->oid_set_request_op(p, oid, data, lenp));
   3429 }
   3430 
   3431 pcap_send_queue *
   3432 pcap_sendqueue_alloc(u_int memsize)
   3433 {
   3434 	pcap_send_queue *tqueue;
   3435 
   3436 	/* Allocate the queue */
   3437 	tqueue = (pcap_send_queue *)malloc(sizeof(pcap_send_queue));
   3438 	if (tqueue == NULL){
   3439 		return (NULL);
   3440 	}
   3441 
   3442 	/* Allocate the buffer */
   3443 	tqueue->buffer = (char *)malloc(memsize);
   3444 	if (tqueue->buffer == NULL) {
   3445 		free(tqueue);
   3446 		return (NULL);
   3447 	}
   3448 
   3449 	tqueue->maxlen = memsize;
   3450 	tqueue->len = 0;
   3451 
   3452 	return (tqueue);
   3453 }
   3454 
   3455 void
   3456 pcap_sendqueue_destroy(pcap_send_queue *queue)
   3457 {
   3458 	free(queue->buffer);
   3459 	free(queue);
   3460 }
   3461 
   3462 int
   3463 pcap_sendqueue_queue(pcap_send_queue *queue, const struct pcap_pkthdr *pkt_header, const u_char *pkt_data)
   3464 {
   3465 	if (queue->len + sizeof(struct pcap_pkthdr) + pkt_header->caplen > queue->maxlen){
   3466 		return (-1);
   3467 	}
   3468 
   3469 	/* Copy the pcap_pkthdr header*/
   3470 	memcpy(queue->buffer + queue->len, pkt_header, sizeof(struct pcap_pkthdr));
   3471 	queue->len += sizeof(struct pcap_pkthdr);
   3472 
   3473 	/* copy the packet */
   3474 	memcpy(queue->buffer + queue->len, pkt_data, pkt_header->caplen);
   3475 	queue->len += pkt_header->caplen;
   3476 
   3477 	return (0);
   3478 }
   3479 
   3480 u_int
   3481 pcap_sendqueue_transmit(pcap_t *p, pcap_send_queue *queue, int sync)
   3482 {
   3483 	return (p->sendqueue_transmit_op(p, queue, sync));
   3484 }
   3485 
   3486 int
   3487 pcap_setuserbuffer(pcap_t *p, int size)
   3488 {
   3489 	return (p->setuserbuffer_op(p, size));
   3490 }
   3491 
   3492 int
   3493 pcap_live_dump(pcap_t *p, char *filename, int maxsize, int maxpacks)
   3494 {
   3495 	return (p->live_dump_op(p, filename, maxsize, maxpacks));
   3496 }
   3497 
   3498 int
   3499 pcap_live_dump_ended(pcap_t *p, int sync)
   3500 {
   3501 	return (p->live_dump_ended_op(p, sync));
   3502 }
   3503 
   3504 PAirpcapHandle
   3505 pcap_get_airpcap_handle(pcap_t *p)
   3506 {
   3507 	PAirpcapHandle handle;
   3508 
   3509 	handle = p->get_airpcap_handle_op(p);
   3510 	if (handle == NULL) {
   3511 		(void)pcap_snprintf(p->errbuf, sizeof(p->errbuf),
   3512 		    "This isn't an AirPcap device");
   3513 	}
   3514 	return (handle);
   3515 }
   3516 #endif
   3517 
   3518 /*
   3519  * On some platforms, we need to clean up promiscuous or monitor mode
   3520  * when we close a device - and we want that to happen even if the
   3521  * application just exits without explicitl closing devices.
   3522  * On those platforms, we need to register a "close all the pcaps"
   3523  * routine to be called when we exit, and need to maintain a list of
   3524  * pcaps that need to be closed to clean up modes.
   3525  *
   3526  * XXX - not thread-safe.
   3527  */
   3528 
   3529 /*
   3530  * List of pcaps on which we've done something that needs to be
   3531  * cleaned up.
   3532  * If there are any such pcaps, we arrange to call "pcap_close_all()"
   3533  * when we exit, and have it close all of them.
   3534  */
   3535 static struct pcap *pcaps_to_close;
   3536 
   3537 /*
   3538  * TRUE if we've already called "atexit()" to cause "pcap_close_all()" to
   3539  * be called on exit.
   3540  */
   3541 static int did_atexit;
   3542 
   3543 static void
   3544 pcap_close_all(void)
   3545 {
   3546 	struct pcap *handle;
   3547 
   3548 	while ((handle = pcaps_to_close) != NULL)
   3549 		pcap_close(handle);
   3550 }
   3551 
   3552 int
   3553 pcap_do_addexit(pcap_t *p)
   3554 {
   3555 	/*
   3556 	 * If we haven't already done so, arrange to have
   3557 	 * "pcap_close_all()" called when we exit.
   3558 	 */
   3559 	if (!did_atexit) {
   3560 		if (atexit(pcap_close_all) != 0) {
   3561 			/*
   3562 			 * "atexit()" failed; let our caller know.
   3563 			 */
   3564 			strlcpy(p->errbuf, "atexit failed", PCAP_ERRBUF_SIZE);
   3565 			return (0);
   3566 		}
   3567 		did_atexit = 1;
   3568 	}
   3569 	return (1);
   3570 }
   3571 
   3572 void
   3573 pcap_add_to_pcaps_to_close(pcap_t *p)
   3574 {
   3575 	p->next = pcaps_to_close;
   3576 	pcaps_to_close = p;
   3577 }
   3578 
   3579 void
   3580 pcap_remove_from_pcaps_to_close(pcap_t *p)
   3581 {
   3582 	pcap_t *pc, *prevpc;
   3583 
   3584 	for (pc = pcaps_to_close, prevpc = NULL; pc != NULL;
   3585 	    prevpc = pc, pc = pc->next) {
   3586 		if (pc == p) {
   3587 			/*
   3588 			 * Found it.  Remove it from the list.
   3589 			 */
   3590 			if (prevpc == NULL) {
   3591 				/*
   3592 				 * It was at the head of the list.
   3593 				 */
   3594 				pcaps_to_close = pc->next;
   3595 			} else {
   3596 				/*
   3597 				 * It was in the middle of the list.
   3598 				 */
   3599 				prevpc->next = pc->next;
   3600 			}
   3601 			break;
   3602 		}
   3603 	}
   3604 }
   3605 
   3606 void
   3607 pcap_cleanup_live_common(pcap_t *p)
   3608 {
   3609 	if (p->buffer != NULL) {
   3610 		free(p->buffer);
   3611 		p->buffer = NULL;
   3612 	}
   3613 	if (p->dlt_list != NULL) {
   3614 		free(p->dlt_list);
   3615 		p->dlt_list = NULL;
   3616 		p->dlt_count = 0;
   3617 	}
   3618 	if (p->tstamp_type_list != NULL) {
   3619 		free(p->tstamp_type_list);
   3620 		p->tstamp_type_list = NULL;
   3621 		p->tstamp_type_count = 0;
   3622 	}
   3623 	if (p->tstamp_precision_list != NULL) {
   3624 		free(p->tstamp_precision_list);
   3625 		p->tstamp_precision_list = NULL;
   3626 		p->tstamp_precision_count = 0;
   3627 	}
   3628 	pcap_freecode(&p->fcode);
   3629 #if !defined(_WIN32) && !defined(MSDOS)
   3630 	if (p->fd >= 0) {
   3631 		close(p->fd);
   3632 		p->fd = -1;
   3633 	}
   3634 	p->selectable_fd = -1;
   3635 #endif
   3636 }
   3637 
   3638 /*
   3639  * API compatible with WinPcap's "send a packet" routine - returns -1
   3640  * on error, 0 otherwise.
   3641  *
   3642  * XXX - what if we get a short write?
   3643  */
   3644 int
   3645 pcap_sendpacket(pcap_t *p, const u_char *buf, int size)
   3646 {
   3647 	if (p->inject_op(p, buf, size) == -1)
   3648 		return (-1);
   3649 	return (0);
   3650 }
   3651 
   3652 /*
   3653  * API compatible with OpenBSD's "send a packet" routine - returns -1 on
   3654  * error, number of bytes written otherwise.
   3655  */
   3656 int
   3657 pcap_inject(pcap_t *p, const void *buf, size_t size)
   3658 {
   3659 	return (p->inject_op(p, buf, size));
   3660 }
   3661 
   3662 void
   3663 pcap_close(pcap_t *p)
   3664 {
   3665 	if (p->opt.device != NULL)
   3666 		free(p->opt.device);
   3667 	p->cleanup_op(p);
   3668 	free(p);
   3669 }
   3670 
   3671 /*
   3672  * Given a BPF program, a pcap_pkthdr structure for a packet, and the raw
   3673  * data for the packet, check whether the packet passes the filter.
   3674  * Returns the return value of the filter program, which will be zero if
   3675  * the packet doesn't pass and non-zero if the packet does pass.
   3676  */
   3677 int
   3678 pcap_offline_filter(const struct bpf_program *fp, const struct pcap_pkthdr *h,
   3679     const u_char *pkt)
   3680 {
   3681 	const struct bpf_insn *fcode = fp->bf_insns;
   3682 
   3683 	if (fcode != NULL)
   3684 		return (bpf_filter(fcode, pkt, h->len, h->caplen));
   3685 	else
   3686 		return (0);
   3687 }
   3688 
   3689 static int
   3690 pcap_can_set_rfmon_dead(pcap_t *p)
   3691 {
   3692 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
   3693 	    "Rfmon mode doesn't apply on a pcap_open_dead pcap_t");
   3694 	return (PCAP_ERROR);
   3695 }
   3696 
   3697 static int
   3698 pcap_read_dead(pcap_t *p, int cnt _U_, pcap_handler callback _U_,
   3699     u_char *user _U_)
   3700 {
   3701 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
   3702 	    "Packets aren't available from a pcap_open_dead pcap_t");
   3703 	return (-1);
   3704 }
   3705 
   3706 static int
   3707 pcap_inject_dead(pcap_t *p, const void *buf _U_, size_t size _U_)
   3708 {
   3709 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
   3710 	    "Packets can't be sent on a pcap_open_dead pcap_t");
   3711 	return (-1);
   3712 }
   3713 
   3714 static int
   3715 pcap_setfilter_dead(pcap_t *p, struct bpf_program *fp _U_)
   3716 {
   3717 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
   3718 	    "A filter cannot be set on a pcap_open_dead pcap_t");
   3719 	return (-1);
   3720 }
   3721 
   3722 static int
   3723 pcap_setdirection_dead(pcap_t *p, pcap_direction_t d _U_)
   3724 {
   3725 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
   3726 	    "The packet direction cannot be set on a pcap_open_dead pcap_t");
   3727 	return (-1);
   3728 }
   3729 
   3730 static int
   3731 pcap_set_datalink_dead(pcap_t *p, int dlt _U_)
   3732 {
   3733 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
   3734 	    "The link-layer header type cannot be set on a pcap_open_dead pcap_t");
   3735 	return (-1);
   3736 }
   3737 
   3738 static int
   3739 pcap_getnonblock_dead(pcap_t *p)
   3740 {
   3741 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
   3742 	    "A pcap_open_dead pcap_t does not have a non-blocking mode setting");
   3743 	return (-1);
   3744 }
   3745 
   3746 static int
   3747 pcap_setnonblock_dead(pcap_t *p, int nonblock _U_)
   3748 {
   3749 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
   3750 	    "A pcap_open_dead pcap_t does not have a non-blocking mode setting");
   3751 	return (-1);
   3752 }
   3753 
   3754 static int
   3755 pcap_stats_dead(pcap_t *p, struct pcap_stat *ps _U_)
   3756 {
   3757 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
   3758 	    "Statistics aren't available from a pcap_open_dead pcap_t");
   3759 	return (-1);
   3760 }
   3761 
   3762 #ifdef _WIN32
   3763 struct pcap_stat *
   3764 pcap_stats_ex_dead(pcap_t *p, int *pcap_stat_size _U_)
   3765 {
   3766 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
   3767 	    "Statistics aren't available from a pcap_open_dead pcap_t");
   3768 	return (NULL);
   3769 }
   3770 
   3771 static int
   3772 pcap_setbuff_dead(pcap_t *p, int dim)
   3773 {
   3774 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
   3775 	    "The kernel buffer size cannot be set on a pcap_open_dead pcap_t");
   3776 	return (-1);
   3777 }
   3778 
   3779 static int
   3780 pcap_setmode_dead(pcap_t *p, int mode)
   3781 {
   3782 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
   3783 	    "impossible to set mode on a pcap_open_dead pcap_t");
   3784 	return (-1);
   3785 }
   3786 
   3787 static int
   3788 pcap_setmintocopy_dead(pcap_t *p, int size)
   3789 {
   3790 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
   3791 	    "The mintocopy parameter cannot be set on a pcap_open_dead pcap_t");
   3792 	return (-1);
   3793 }
   3794 
   3795 static HANDLE
   3796 pcap_getevent_dead(pcap_t *p)
   3797 {
   3798 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
   3799 	    "A pcap_open_dead pcap_t has no event handle");
   3800 	return (INVALID_HANDLE_VALUE);
   3801 }
   3802 
   3803 static int
   3804 pcap_oid_get_request_dead(pcap_t *p, bpf_u_int32 oid _U_, void *data _U_,
   3805     size_t *lenp _U_)
   3806 {
   3807 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
   3808 	    "An OID get request cannot be performed on a pcap_open_dead pcap_t");
   3809 	return (PCAP_ERROR);
   3810 }
   3811 
   3812 static int
   3813 pcap_oid_set_request_dead(pcap_t *p, bpf_u_int32 oid _U_, const void *data _U_,
   3814     size_t *lenp _U_)
   3815 {
   3816 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
   3817 	    "An OID set request cannot be performed on a pcap_open_dead pcap_t");
   3818 	return (PCAP_ERROR);
   3819 }
   3820 
   3821 static u_int
   3822 pcap_sendqueue_transmit_dead(pcap_t *p, pcap_send_queue *queue, int sync)
   3823 {
   3824 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
   3825 	    "Packets cannot be transmitted on a pcap_open_dead pcap_t");
   3826 	return (0);
   3827 }
   3828 
   3829 static int
   3830 pcap_setuserbuffer_dead(pcap_t *p, int size)
   3831 {
   3832 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
   3833 	    "The user buffer cannot be set on a pcap_open_dead pcap_t");
   3834 	return (-1);
   3835 }
   3836 
   3837 static int
   3838 pcap_live_dump_dead(pcap_t *p, char *filename, int maxsize, int maxpacks)
   3839 {
   3840 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
   3841 	    "Live packet dumping cannot be performed on a pcap_open_dead pcap_t");
   3842 	return (-1);
   3843 }
   3844 
   3845 static int
   3846 pcap_live_dump_ended_dead(pcap_t *p, int sync)
   3847 {
   3848 	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
   3849 	    "Live packet dumping cannot be performed on a pcap_open_dead pcap_t");
   3850 	return (-1);
   3851 }
   3852 
   3853 static PAirpcapHandle
   3854 pcap_get_airpcap_handle_dead(pcap_t *p)
   3855 {
   3856 	return (NULL);
   3857 }
   3858 #endif /* _WIN32 */
   3859 
   3860 static void
   3861 pcap_cleanup_dead(pcap_t *p _U_)
   3862 {
   3863 	/* Nothing to do. */
   3864 }
   3865 
   3866 pcap_t *
   3867 pcap_open_dead_with_tstamp_precision(int linktype, int snaplen, u_int precision)
   3868 {
   3869 	pcap_t *p;
   3870 
   3871 	switch (precision) {
   3872 
   3873 	case PCAP_TSTAMP_PRECISION_MICRO:
   3874 	case PCAP_TSTAMP_PRECISION_NANO:
   3875 		break;
   3876 
   3877 	default:
   3878 		/*
   3879 		 * This doesn't really matter, but we don't have any way
   3880 		 * to report particular errors, so the only failure we
   3881 		 * should have is a memory allocation failure.  Just
   3882 		 * pick microsecond precision.
   3883 		 */
   3884 		precision = PCAP_TSTAMP_PRECISION_MICRO;
   3885 		break;
   3886 	}
   3887 	p = malloc(sizeof(*p));
   3888 	if (p == NULL)
   3889 		return NULL;
   3890 	memset (p, 0, sizeof(*p));
   3891 	p->snapshot = snaplen;
   3892 	p->linktype = linktype;
   3893 	p->opt.tstamp_precision = precision;
   3894 	p->can_set_rfmon_op = pcap_can_set_rfmon_dead;
   3895 	p->read_op = pcap_read_dead;
   3896 	p->inject_op = pcap_inject_dead;
   3897 	p->setfilter_op = pcap_setfilter_dead;
   3898 	p->setdirection_op = pcap_setdirection_dead;
   3899 	p->set_datalink_op = pcap_set_datalink_dead;
   3900 	p->getnonblock_op = pcap_getnonblock_dead;
   3901 	p->setnonblock_op = pcap_setnonblock_dead;
   3902 	p->stats_op = pcap_stats_dead;
   3903 #ifdef _WIN32
   3904 	p->stats_ex_op = pcap_stats_ex_dead;
   3905 	p->setbuff_op = pcap_setbuff_dead;
   3906 	p->setmode_op = pcap_setmode_dead;
   3907 	p->setmintocopy_op = pcap_setmintocopy_dead;
   3908 	p->getevent_op = pcap_getevent_dead;
   3909 	p->oid_get_request_op = pcap_oid_get_request_dead;
   3910 	p->oid_set_request_op = pcap_oid_set_request_dead;
   3911 	p->sendqueue_transmit_op = pcap_sendqueue_transmit_dead;
   3912 	p->setuserbuffer_op = pcap_setuserbuffer_dead;
   3913 	p->live_dump_op = pcap_live_dump_dead;
   3914 	p->live_dump_ended_op = pcap_live_dump_ended_dead;
   3915 	p->get_airpcap_handle_op = pcap_get_airpcap_handle_dead;
   3916 #endif
   3917 	p->cleanup_op = pcap_cleanup_dead;
   3918 
   3919 	/*
   3920 	 * A "dead" pcap_t never requires special BPF code generation.
   3921 	 */
   3922 	p->bpf_codegen_flags = 0;
   3923 
   3924 	p->activated = 1;
   3925 	return (p);
   3926 }
   3927 
   3928 pcap_t *
   3929 pcap_open_dead(int linktype, int snaplen)
   3930 {
   3931 	return (pcap_open_dead_with_tstamp_precision(linktype, snaplen,
   3932 	    PCAP_TSTAMP_PRECISION_MICRO));
   3933 }
   3934 
   3935 #ifdef YYDEBUG
   3936 /*
   3937  * Set the internal "debug printout" flag for the filter expression parser.
   3938  * The code to print that stuff is present only if YYDEBUG is defined, so
   3939  * the flag, and the routine to set it, are defined only if YYDEBUG is
   3940  * defined.
   3941  *
   3942  * This is intended for libpcap developers, not for general use.
   3943  * If you want to set these in a program, you'll have to declare this
   3944  * routine yourself, with the appropriate DLL import attribute on Windows;
   3945  * it's not declared in any header file, and won't be declared in any
   3946  * header file provided by libpcap.
   3947  */
   3948 PCAP_API void pcap_set_parser_debug(int value);
   3949 
   3950 PCAP_API_DEF void
   3951 pcap_set_parser_debug(int value)
   3952 {
   3953 	pcap_debug = value;
   3954 }
   3955 #endif
   3956