xref: /freebsd/contrib/libpcap/pcap/pcap.h (revision afdbf109c6a661a729938f68211054a0a50d38ac)
1 /* -*- Mode: c; tab-width: 8; indent-tabs-mode: 1; c-basic-offset: 8; -*- */
2 /*
3  * Copyright (c) 1993, 1994, 1995, 1996, 1997
4  *	The Regents of the University of California.  All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. All advertising materials mentioning features or use of this software
15  *    must display the following acknowledgement:
16  *	This product includes software developed by the Computer Systems
17  *	Engineering Group at Lawrence Berkeley Laboratory.
18  * 4. Neither the name of the University nor of the Laboratory may be used
19  *    to endorse or promote products derived from this software without
20  *    specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 /*
36  * Remote packet capture mechanisms and extensions from WinPcap:
37  *
38  * Copyright (c) 2002 - 2003
39  * NetGroup, Politecnico di Torino (Italy)
40  * All rights reserved.
41  *
42  * Redistribution and use in source and binary forms, with or without
43  * modification, are permitted provided that the following conditions
44  * are met:
45  *
46  * 1. Redistributions of source code must retain the above copyright
47  * notice, this list of conditions and the following disclaimer.
48  * 2. Redistributions in binary form must reproduce the above copyright
49  * notice, this list of conditions and the following disclaimer in the
50  * documentation and/or other materials provided with the distribution.
51  * 3. Neither the name of the Politecnico di Torino nor the names of its
52  * contributors may be used to endorse or promote products derived from
53  * this software without specific prior written permission.
54  *
55  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
56  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
57  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
58  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
59  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
60  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
61  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
62  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
63  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
64  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
65  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
66  *
67  */
68 
69 #ifndef lib_pcap_pcap_h
70 #define lib_pcap_pcap_h
71 
72 /*
73  * Some software that uses libpcap/WinPcap/Npcap defines _MSC_VER before
74  * including pcap.h if it's not defined - and it defines it to 1500.
75  * (I'm looking at *you*, lwIP!)
76  *
77  * Attempt to detect this, and undefine _MSC_VER so that we can *reliably*
78  * use it to know what compiler is being used and, if it's Visual Studio,
79  * what version is being used.
80  */
81 #if defined(_MSC_VER)
82   /*
83    * We assume here that software such as that doesn't define _MSC_FULL_VER
84    * as well and that it defines _MSC_VER with a value > 1200.
85    *
86    * DO NOT BREAK THESE ASSUMPTIONS.  IF YOU FEEL YOU MUST DEFINE _MSC_VER
87    * WITH A COMPILER THAT'S NOT MICROSOFT'S C COMPILER, PLEASE CONTACT
88    * US SO THAT WE CAN MAKE IT SO THAT YOU DON'T HAVE TO DO THAT.  THANK
89    * YOU.
90    *
91    * OK, is _MSC_FULL_VER defined?
92    */
93   #if !defined(_MSC_FULL_VER)
94     /*
95      * According to
96      *
97      *    https://sourceforge.net/p/predef/wiki/Compilers/
98      *
99      * with "Visual C++ 6.0 Processor Pack"/Visual C++ 6.0 SP6 and
100      * later, _MSC_FULL_VER is defined, so either this is an older
101      * version of Visual C++ or it's not Visual C++ at all.
102      *
103      * For Visual C++ 6.0, _MSC_VER is defined as 1200.
104      */
105     #if _MSC_VER > 1200
106       /*
107        * If this is Visual C++, _MSC_FULL_VER should be defined, so we
108        * assume this isn't Visual C++, and undo the lie that it is.
109        */
110       #undef _MSC_VER
111     #endif
112   #endif
113 #endif
114 
115 #include <pcap/funcattrs.h>
116 
117 #include <pcap/pcap-inttypes.h>
118 
119 #if defined(_WIN32)
120   #include <winsock2.h>		/* u_int, u_char etc. */
121   #include <io.h>		/* _get_osfhandle() */
122 #elif defined(MSDOS)
123   #include <sys/types.h>	/* u_int, u_char etc. */
124   #include <sys/socket.h>
125 #else /* UN*X */
126   #include <sys/types.h>	/* u_int, u_char etc. */
127   #include <sys/time.h>
128 #endif /* _WIN32/MSDOS/UN*X */
129 
130 #include <pcap/socket.h>	/* for PCAP_SOCKET, as the active-mode rpcap APIs use it */
131 
132 #ifndef PCAP_DONT_INCLUDE_PCAP_BPF_H
133 #include <pcap/bpf.h>
134 #endif
135 
136 #include <stdio.h>
137 
138 #ifdef __cplusplus
139 extern "C" {
140 #endif
141 
142 /*
143  * Version number of the current version of the pcap file format.
144  *
145  * NOTE: this is *NOT* the version number of the libpcap library.
146  * To fetch the version information for the version of libpcap
147  * you're using, use pcap_lib_version().
148  */
149 #define PCAP_VERSION_MAJOR 2
150 #define PCAP_VERSION_MINOR 4
151 
152 #define PCAP_ERRBUF_SIZE 256
153 
154 /*
155  * Compatibility for systems that have a bpf.h that
156  * predates the bpf typedefs for 64-bit support.
157  */
158 #if BPF_RELEASE - 0 < 199406
159 typedef	int bpf_int32;
160 typedef	u_int bpf_u_int32;
161 #endif
162 
163 typedef struct pcap pcap_t;
164 typedef struct pcap_dumper pcap_dumper_t;
165 typedef struct pcap_if pcap_if_t;
166 typedef struct pcap_addr pcap_addr_t;
167 
168 /*
169  * The first record in the file contains saved values for some
170  * of the flags used in the printout phases of tcpdump.
171  * Many fields here are 32 bit ints so compilers won't insert unwanted
172  * padding; these files need to be interchangeable across architectures.
173  * Documentation: https://www.tcpdump.org/manpages/pcap-savefile.5.txt.
174  *
175  * Do not change the layout of this structure, in any way (this includes
176  * changes that only affect the length of fields in this structure).
177  *
178  * Also, do not change the interpretation of any of the members of this
179  * structure, in any way (this includes using values other than
180  * LINKTYPE_ values, as defined in "savefile.c", in the "linktype"
181  * field).
182  *
183  * Instead:
184  *
185  *	introduce a new structure for the new format, if the layout
186  *	of the structure changed;
187  *
188  *	send mail to "tcpdump-workers@lists.tcpdump.org", requesting
189  *	a new magic number for your new capture file format, and, when
190  *	you get the new magic number, put it in "savefile.c";
191  *
192  *	use that magic number for save files with the changed file
193  *	header;
194  *
195  *	make the code in "savefile.c" capable of reading files with
196  *	the old file header as well as files with the new file header
197  *	(using the magic number to determine the header format).
198  *
199  * Then supply the changes by forking the branch at
200  *
201  *	https://github.com/the-tcpdump-group/libpcap/tree/master
202  *
203  * and issuing a pull request, so that future versions of libpcap and
204  * programs that use it (such as tcpdump) will be able to read your new
205  * capture file format.
206  */
207 struct pcap_file_header {
208 	bpf_u_int32 magic;
209 	u_short version_major;
210 	u_short version_minor;
211 	bpf_int32 thiszone;	/* not used - SHOULD be filled with 0 */
212 	bpf_u_int32 sigfigs;	/* not used - SHOULD be filled with 0 */
213 	bpf_u_int32 snaplen;	/* max length saved portion of each pkt */
214 	bpf_u_int32 linktype;	/* data link type (LINKTYPE_*) */
215 };
216 
217 /*
218  * Subfields of the field containing the link-layer header type.
219  *
220  * Link-layer header types are assigned for both pcap and
221  * pcapng, and the same value must work with both.  In pcapng,
222  * the link-layer header type field in an Interface Description
223  * Block is 16 bits, so only the bottommost 16 bits of the
224  * link-layer header type in a pcap file can be used for the
225  * header type value.
226  *
227  * In libpcap, the upper 16 bits, from the top down, are divided into:
228  *
229  *    A 4-bit "FCS length" field, to allow the FCS length to
230  *    be specified, just as it can be specified in the if_fcslen
231  *    field of the pcapng IDB.  The field is in units of 16 bits,
232  *    i.e. 1 means 16 bits of FCS, 2 means 32 bits of FCS, etc..
233  *
234  *    A reserved bit, which must be zero.
235  *
236  *    An "FCS length present" flag; if 0, the "FCS length" field
237  *    should be ignored, and if 1, the "FCS length" field should
238  *    be used.
239  *
240  *    10 reserved bits, which must be zero.  They were originally
241  *    intended to be used as a "class" field, allowing additional
242  *    classes of link-layer types to be defined, with a class value
243  *    of 0 indicating that the link-layer type is a LINKTYPE_ value.
244  *    A value of 0x224 was, at one point, used by NetBSD to define
245  *    "raw" packet types, with the lower 16 bits containing a
246  *    NetBSD AF_ value; see
247  *
248  *        https://marc.info/?l=tcpdump-workers&m=98296750229149&w=2
249  *
250  *    It's unknown whether those were ever used in capture files,
251  *    or if the intent was just to use it as a link-layer type
252  *    for BPF programs; NetBSD's libpcap used to support them in
253  *    the BPF code generator, but it no longer does so.  If it
254  *    was ever used in capture files, or if classes other than
255  *    "LINKTYPE_ value" are ever useful in capture files, we could
256  *    re-enable this, and use the reserved 16 bits following the
257  *    link-layer type in pcapng files to hold the class information
258  *    there.  (Note, BTW, that LINKTYPE_RAW/DLT_RAW is now being
259  *    interpreted by libpcap, tcpdump, and Wireshark as "raw IP",
260  *    including both IPv4 and IPv6, with the version number in the
261  *    header being checked to see which it is, not just "raw IPv4";
262  *    there are LINKTYPE_IPV4/DLT_IPV4 and LINKTYPE_IPV6/DLT_IPV6
263  *    values if "these are IPv{4,6} and only IPv{4,6} packets"
264  *    types are needed.)
265  *
266  *    Or we might be able to use it for other purposes.
267  */
268 #define LT_LINKTYPE(x)			((x) & 0x0000FFFF)
269 #define LT_LINKTYPE_EXT(x)		((x) & 0xFFFF0000)
270 #define LT_RESERVED1(x)			((x) & 0x03FF0000)
271 #define LT_FCS_LENGTH_PRESENT(x)	((x) & 0x04000000)
272 #define LT_FCS_LENGTH(x)		(((x) & 0xF0000000) >> 28)
273 #define LT_FCS_DATALINK_EXT(x)		((((x) & 0xF) << 28) | 0x04000000)
274 
275 typedef enum {
276        PCAP_D_INOUT = 0,
277        PCAP_D_IN,
278        PCAP_D_OUT
279 } pcap_direction_t;
280 
281 /*
282  * Generic per-packet information, as supplied by libpcap.
283  *
284  * The time stamp can and should be a "struct timeval", regardless of
285  * whether your system supports 32-bit tv_sec in "struct timeval",
286  * 64-bit tv_sec in "struct timeval", or both if it supports both 32-bit
287  * and 64-bit applications.  The on-disk format of savefiles uses 32-bit
288  * tv_sec (and tv_usec); this structure is irrelevant to that.  32-bit
289  * and 64-bit versions of libpcap, even if they're on the same platform,
290  * should supply the appropriate version of "struct timeval", even if
291  * that's not what the underlying packet capture mechanism supplies.
292  */
293 struct pcap_pkthdr {
294 	struct timeval ts;	/* time stamp */
295 	bpf_u_int32 caplen;	/* length of portion present */
296 	bpf_u_int32 len;	/* length of this packet (off wire) */
297 };
298 
299 /*
300  * As returned by the pcap_stats()
301  */
302 struct pcap_stat {
303 	u_int ps_recv;		/* number of packets received */
304 	u_int ps_drop;		/* number of packets dropped */
305 	u_int ps_ifdrop;	/* drops by interface -- only supported on some platforms */
306 #ifdef _WIN32
307 	u_int ps_capt;		/* number of packets that reach the application */
308 	u_int ps_sent;		/* number of packets sent by the server on the network */
309 	u_int ps_netdrop;	/* number of packets lost on the network */
310 #endif /* _WIN32 */
311 };
312 
313 #ifdef MSDOS
314 /*
315  * As returned by the pcap_stats_ex()
316  */
317 struct pcap_stat_ex {
318        u_long  rx_packets;        /* total packets received       */
319        u_long  tx_packets;        /* total packets transmitted    */
320        u_long  rx_bytes;          /* total bytes received         */
321        u_long  tx_bytes;          /* total bytes transmitted      */
322        u_long  rx_errors;         /* bad packets received         */
323        u_long  tx_errors;         /* packet transmit problems     */
324        u_long  rx_dropped;        /* no space in Rx buffers       */
325        u_long  tx_dropped;        /* no space available for Tx    */
326        u_long  multicast;         /* multicast packets received   */
327        u_long  collisions;
328 
329        /* detailed rx_errors: */
330        u_long  rx_length_errors;
331        u_long  rx_over_errors;    /* receiver ring buff overflow  */
332        u_long  rx_crc_errors;     /* recv'd pkt with crc error    */
333        u_long  rx_frame_errors;   /* recv'd frame alignment error */
334        u_long  rx_fifo_errors;    /* recv'r fifo overrun          */
335        u_long  rx_missed_errors;  /* recv'r missed packet         */
336 
337        /* detailed tx_errors */
338        u_long  tx_aborted_errors;
339        u_long  tx_carrier_errors;
340        u_long  tx_fifo_errors;
341        u_long  tx_heartbeat_errors;
342        u_long  tx_window_errors;
343      };
344 #endif
345 
346 /*
347  * Item in a list of interfaces.
348  */
349 struct pcap_if {
350 	struct pcap_if *next;
351 	char *name;		/* name to hand to "pcap_open_live()" */
352 	char *description;	/* textual description of interface, or NULL */
353 	struct pcap_addr *addresses;
354 	bpf_u_int32 flags;	/* PCAP_IF_ interface flags */
355 };
356 
357 #define PCAP_IF_LOOPBACK				0x00000001	/* interface is loopback */
358 #define PCAP_IF_UP					0x00000002	/* interface is up */
359 #define PCAP_IF_RUNNING					0x00000004	/* interface is running */
360 #define PCAP_IF_WIRELESS				0x00000008	/* interface is wireless (*NOT* necessarily Wi-Fi!) */
361 #define PCAP_IF_CONNECTION_STATUS			0x00000030	/* connection status: */
362 #define PCAP_IF_CONNECTION_STATUS_UNKNOWN		0x00000000	/* unknown */
363 #define PCAP_IF_CONNECTION_STATUS_CONNECTED		0x00000010	/* connected */
364 #define PCAP_IF_CONNECTION_STATUS_DISCONNECTED		0x00000020	/* disconnected */
365 #define PCAP_IF_CONNECTION_STATUS_NOT_APPLICABLE	0x00000030	/* not applicable */
366 
367 /*
368  * Representation of an interface address.
369  */
370 struct pcap_addr {
371 	struct pcap_addr *next;
372 	struct sockaddr *addr;		/* address */
373 	struct sockaddr *netmask;	/* netmask for that address */
374 	struct sockaddr *broadaddr;	/* broadcast address for that address */
375 	struct sockaddr *dstaddr;	/* P2P destination address for that address */
376 };
377 
378 typedef void (*pcap_handler)(u_char *, const struct pcap_pkthdr *,
379 			     const u_char *);
380 
381 /*
382  * Error codes for the pcap API.
383  * These will all be negative, so you can check for the success or
384  * failure of a call that returns these codes by checking for a
385  * negative value.
386  */
387 #define PCAP_ERROR			-1	/* generic error code */
388 #define PCAP_ERROR_BREAK		-2	/* loop terminated by pcap_breakloop */
389 #define PCAP_ERROR_NOT_ACTIVATED	-3	/* the capture needs to be activated */
390 #define PCAP_ERROR_ACTIVATED		-4	/* the operation can't be performed on already activated captures */
391 #define PCAP_ERROR_NO_SUCH_DEVICE	-5	/* no such device exists */
392 #define PCAP_ERROR_RFMON_NOTSUP		-6	/* this device doesn't support rfmon (monitor) mode */
393 #define PCAP_ERROR_NOT_RFMON		-7	/* operation supported only in monitor mode */
394 #define PCAP_ERROR_PERM_DENIED		-8	/* no permission to open the device */
395 #define PCAP_ERROR_IFACE_NOT_UP		-9	/* interface isn't up */
396 #define PCAP_ERROR_CANTSET_TSTAMP_TYPE	-10	/* this device doesn't support setting the time stamp type */
397 #define PCAP_ERROR_PROMISC_PERM_DENIED	-11	/* you don't have permission to capture in promiscuous mode */
398 #define PCAP_ERROR_TSTAMP_PRECISION_NOTSUP -12  /* the requested time stamp precision is not supported */
399 #define PCAP_ERROR_CAPTURE_NOTSUP	-13	/* capture mechanism not available */
400 
401 /*
402  * Warning codes for the pcap API.
403  * These will all be positive and non-zero, so they won't look like
404  * errors.
405  */
406 #define PCAP_WARNING			1	/* generic warning code */
407 #define PCAP_WARNING_PROMISC_NOTSUP	2	/* this device doesn't support promiscuous mode */
408 #define PCAP_WARNING_TSTAMP_TYPE_NOTSUP	3	/* the requested time stamp type is not supported */
409 
410 /*
411  * Value to pass to pcap_compile() as the netmask if you don't know what
412  * the netmask is.
413  */
414 #define PCAP_NETMASK_UNKNOWN	0xffffffff
415 
416 /*
417  * Initialize pcap.  If this isn't called, pcap is initialized to
418  * a mode source-compatible and binary-compatible with older versions
419  * that lack this routine.
420  */
421 
422 /*
423  * Initialization options.
424  * All bits not listed here are reserved for expansion.
425  *
426  * On UNIX-like systems, the local character encoding is assumed to be
427  * UTF-8, so no character encoding transformations are done.
428  *
429  * On Windows, the local character encoding is the local ANSI code page.
430  */
431 #define PCAP_CHAR_ENC_LOCAL	0x00000000U	/* strings are in the local character encoding */
432 #define PCAP_CHAR_ENC_UTF_8	0x00000001U	/* strings are in UTF-8 */
433 
434 PCAP_AVAILABLE_1_10
435 PCAP_API int	pcap_init(unsigned int, char *);
436 
437 /*
438  * We're deprecating pcap_lookupdev() for various reasons (not
439  * thread-safe, can behave weirdly with WinPcap).  Callers
440  * should use pcap_findalldevs() and use the first device.
441  */
442 PCAP_AVAILABLE_0_4
443 PCAP_DEPRECATED("use 'pcap_findalldevs' and use the first device")
444 PCAP_API char	*pcap_lookupdev(char *);
445 
446 PCAP_AVAILABLE_0_4
447 PCAP_API int	pcap_lookupnet(const char *, bpf_u_int32 *, bpf_u_int32 *, char *);
448 
449 PCAP_AVAILABLE_1_0
450 PCAP_API pcap_t	*pcap_create(const char *, char *);
451 
452 PCAP_AVAILABLE_1_0
453 PCAP_API int	pcap_set_snaplen(pcap_t *, int);
454 
455 PCAP_AVAILABLE_1_0
456 PCAP_API int	pcap_set_promisc(pcap_t *, int);
457 
458 PCAP_AVAILABLE_1_0
459 PCAP_API int	pcap_can_set_rfmon(pcap_t *);
460 
461 PCAP_AVAILABLE_1_0
462 PCAP_API int	pcap_set_rfmon(pcap_t *, int);
463 
464 PCAP_AVAILABLE_1_0
465 PCAP_API int	pcap_set_timeout(pcap_t *, int);
466 
467 PCAP_AVAILABLE_1_2
468 PCAP_API int	pcap_set_tstamp_type(pcap_t *, int);
469 
470 PCAP_AVAILABLE_1_5
471 PCAP_API int	pcap_set_immediate_mode(pcap_t *, int);
472 
473 PCAP_AVAILABLE_1_0
474 PCAP_API int	pcap_set_buffer_size(pcap_t *, int);
475 
476 PCAP_AVAILABLE_1_5
477 PCAP_API int	pcap_set_tstamp_precision(pcap_t *, int);
478 
479 PCAP_AVAILABLE_1_5
480 PCAP_API int	pcap_get_tstamp_precision(pcap_t *);
481 
482 PCAP_AVAILABLE_1_0
483 PCAP_API int	pcap_activate(pcap_t *);
484 
485 PCAP_AVAILABLE_1_2
486 PCAP_API int	pcap_list_tstamp_types(pcap_t *, int **);
487 
488 PCAP_AVAILABLE_1_2
489 PCAP_API void	pcap_free_tstamp_types(int *);
490 
491 PCAP_AVAILABLE_1_2
492 PCAP_API int	pcap_tstamp_type_name_to_val(const char *);
493 
494 PCAP_AVAILABLE_1_2
495 PCAP_API const char *pcap_tstamp_type_val_to_name(int);
496 
497 PCAP_AVAILABLE_1_2
498 PCAP_API const char *pcap_tstamp_type_val_to_description(int);
499 
500 #ifdef __linux__
501 PCAP_AVAILABLE_1_9
502 PCAP_API int	pcap_set_protocol_linux(pcap_t *, int);
503 #endif
504 
505 /*
506  * Time stamp types.
507  * Not all systems and interfaces will necessarily support all of these.
508  *
509  * A system that supports PCAP_TSTAMP_HOST is offering time stamps
510  * provided by the host machine, rather than by the capture device,
511  * but not committing to any characteristics of the time stamp.
512  *
513  * PCAP_TSTAMP_HOST_LOWPREC is a time stamp, provided by the host machine,
514  * that's low-precision but relatively cheap to fetch; it's normally done
515  * using the system clock, so it's normally synchronized with times you'd
516  * fetch from system calls.
517  *
518  * PCAP_TSTAMP_HOST_HIPREC is a time stamp, provided by the host machine,
519  * that's high-precision; it might be more expensive to fetch.  It is
520  * synchronized with the system clock.
521  *
522  * PCAP_TSTAMP_HOST_HIPREC_UNSYNCED is a time stamp, provided by the host
523  * machine, that's high-precision; it might be more expensive to fetch.
524  * It is not synchronized with the system clock, and might have
525  * problems with time stamps for packets received on different CPUs,
526  * depending on the platform.  It might be more likely to be strictly
527  * monotonic than PCAP_TSTAMP_HOST_HIPREC.
528  *
529  * PCAP_TSTAMP_ADAPTER is a high-precision time stamp supplied by the
530  * capture device; it's synchronized with the system clock.
531  *
532  * PCAP_TSTAMP_ADAPTER_UNSYNCED is a high-precision time stamp supplied by
533  * the capture device; it's not synchronized with the system clock.
534  *
535  * Note that time stamps synchronized with the system clock can go
536  * backwards, as the system clock can go backwards.  If a clock is
537  * not in sync with the system clock, that could be because the
538  * system clock isn't keeping accurate time, because the other
539  * clock isn't keeping accurate time, or both.
540  *
541  * Note that host-provided time stamps generally correspond to the
542  * time when the time-stamping code sees the packet; this could
543  * be some unknown amount of time after the first or last bit of
544  * the packet is received by the network adapter, due to batching
545  * of interrupts for packet arrival, queueing delays, etc..
546  */
547 #define PCAP_TSTAMP_HOST			0	/* host-provided, unknown characteristics */
548 #define PCAP_TSTAMP_HOST_LOWPREC		1	/* host-provided, low precision, synced with the system clock */
549 #define PCAP_TSTAMP_HOST_HIPREC			2	/* host-provided, high precision, synced with the system clock */
550 #define PCAP_TSTAMP_ADAPTER			3	/* device-provided, synced with the system clock */
551 #define PCAP_TSTAMP_ADAPTER_UNSYNCED		4	/* device-provided, not synced with the system clock */
552 #define PCAP_TSTAMP_HOST_HIPREC_UNSYNCED	5	/* host-provided, high precision, not synced with the system clock */
553 
554 /*
555  * Time stamp resolution types.
556  * Not all systems and interfaces will necessarily support all of these
557  * resolutions when doing live captures; all of them can be requested
558  * when reading a savefile.
559  */
560 #define PCAP_TSTAMP_PRECISION_MICRO	0	/* use timestamps with microsecond precision, default */
561 #define PCAP_TSTAMP_PRECISION_NANO	1	/* use timestamps with nanosecond precision */
562 
563 PCAP_AVAILABLE_0_4
564 PCAP_API pcap_t	*pcap_open_live(const char *, int, int, int, char *);
565 
566 PCAP_AVAILABLE_0_6
567 PCAP_API pcap_t	*pcap_open_dead(int, int);
568 
569 PCAP_AVAILABLE_1_5
570 PCAP_API pcap_t	*pcap_open_dead_with_tstamp_precision(int, int, u_int);
571 
572 PCAP_AVAILABLE_1_5
573 PCAP_API pcap_t	*pcap_open_offline_with_tstamp_precision(const char *, u_int, char *);
574 
575 PCAP_AVAILABLE_0_4
576 PCAP_API pcap_t	*pcap_open_offline(const char *, char *);
577 
578 #ifdef _WIN32
579   PCAP_AVAILABLE_1_5
580   PCAP_API pcap_t  *pcap_hopen_offline_with_tstamp_precision(intptr_t, u_int, char *);
581 
582   PCAP_API pcap_t  *pcap_hopen_offline(intptr_t, char *);
583   /*
584    * If we're building libpcap, these are internal routines in savefile.c,
585    * so we must not define them as macros.
586    *
587    * If we're not building libpcap, given that the version of the C runtime
588    * with which libpcap was built might be different from the version
589    * of the C runtime with which an application using libpcap was built,
590    * and that a FILE structure may differ between the two versions of the
591    * C runtime, calls to _fileno() must use the version of _fileno() in
592    * the C runtime used to open the FILE *, not the version in the C
593    * runtime with which libpcap was built.  (Maybe once the Universal CRT
594    * rules the world, this will cease to be a problem.)
595    */
596   #ifndef BUILDING_PCAP
597     #define pcap_fopen_offline_with_tstamp_precision(f,p,b) \
598 	pcap_hopen_offline_with_tstamp_precision(_get_osfhandle(_fileno(f)), p, b)
599     #define pcap_fopen_offline(f,b) \
600 	pcap_hopen_offline(_get_osfhandle(_fileno(f)), b)
601   #endif
602 #else /*_WIN32*/
603   PCAP_AVAILABLE_1_5
604   PCAP_API pcap_t	*pcap_fopen_offline_with_tstamp_precision(FILE *, u_int, char *);
605 
606   PCAP_AVAILABLE_0_9
607   PCAP_API pcap_t	*pcap_fopen_offline(FILE *, char *);
608 #endif /*_WIN32*/
609 
610 PCAP_AVAILABLE_0_4
611 PCAP_API void	pcap_close(pcap_t *);
612 
613 PCAP_AVAILABLE_0_4
614 PCAP_API int	pcap_loop(pcap_t *, int, pcap_handler, u_char *);
615 
616 PCAP_AVAILABLE_0_4
617 PCAP_API int	pcap_dispatch(pcap_t *, int, pcap_handler, u_char *);
618 
619 PCAP_AVAILABLE_0_4
620 PCAP_API const u_char *pcap_next(pcap_t *, struct pcap_pkthdr *);
621 
622 PCAP_AVAILABLE_0_8
623 PCAP_API int	pcap_next_ex(pcap_t *, struct pcap_pkthdr **, const u_char **);
624 
625 PCAP_AVAILABLE_0_8
626 PCAP_API void	pcap_breakloop(pcap_t *);
627 
628 PCAP_AVAILABLE_0_4
629 PCAP_API int	pcap_stats(pcap_t *, struct pcap_stat *);
630 
631 PCAP_AVAILABLE_0_4
632 PCAP_API int	pcap_setfilter(pcap_t *, struct bpf_program *);
633 
634 PCAP_AVAILABLE_0_9
635 PCAP_API int	pcap_setdirection(pcap_t *, pcap_direction_t);
636 
637 PCAP_AVAILABLE_0_7
638 PCAP_API int	pcap_getnonblock(pcap_t *, char *);
639 
640 PCAP_AVAILABLE_0_7
641 PCAP_API int	pcap_setnonblock(pcap_t *, int, char *);
642 
643 PCAP_AVAILABLE_0_9
644 PCAP_API int	pcap_inject(pcap_t *, const void *, size_t);
645 
646 PCAP_AVAILABLE_0_8
647 PCAP_API int	pcap_sendpacket(pcap_t *, const u_char *, int);
648 
649 PCAP_AVAILABLE_1_0
650 PCAP_API const char *pcap_statustostr(int);
651 
652 PCAP_AVAILABLE_0_4
653 PCAP_API const char *pcap_strerror(int);
654 
655 PCAP_AVAILABLE_0_4
656 PCAP_API char	*pcap_geterr(pcap_t *);
657 
658 PCAP_AVAILABLE_0_4
659 PCAP_API void	pcap_perror(pcap_t *, const char *);
660 
661 PCAP_AVAILABLE_0_4
662 PCAP_API int	pcap_compile(pcap_t *, struct bpf_program *, const char *, int,
663 	    bpf_u_int32);
664 
665 PCAP_AVAILABLE_0_5
666 PCAP_DEPRECATED("use pcap_open_dead(), pcap_compile() and pcap_close()")
667 PCAP_API int	pcap_compile_nopcap(int, int, struct bpf_program *,
668 	    const char *, int, bpf_u_int32);
669 
670 /* XXX - this took two arguments in 0.4 and 0.5 */
671 PCAP_AVAILABLE_0_6
672 PCAP_API void	pcap_freecode(struct bpf_program *);
673 
674 PCAP_AVAILABLE_1_0
675 PCAP_API int	pcap_offline_filter(const struct bpf_program *,
676 	    const struct pcap_pkthdr *, const u_char *);
677 
678 PCAP_AVAILABLE_0_4
679 PCAP_API int	pcap_datalink(pcap_t *);
680 
681 PCAP_AVAILABLE_1_0
682 PCAP_API int	pcap_datalink_ext(pcap_t *);
683 
684 PCAP_AVAILABLE_0_8
685 PCAP_API int	pcap_list_datalinks(pcap_t *, int **);
686 
687 PCAP_AVAILABLE_0_8
688 PCAP_API int	pcap_set_datalink(pcap_t *, int);
689 
690 PCAP_AVAILABLE_0_8
691 PCAP_API void	pcap_free_datalinks(int *);
692 
693 PCAP_AVAILABLE_0_8
694 PCAP_API int	pcap_datalink_name_to_val(const char *);
695 
696 PCAP_AVAILABLE_0_8
697 PCAP_API const char *pcap_datalink_val_to_name(int);
698 
699 PCAP_AVAILABLE_0_8
700 PCAP_API const char *pcap_datalink_val_to_description(int);
701 
702 PCAP_AVAILABLE_1_9
703 PCAP_API const char *pcap_datalink_val_to_description_or_dlt(int);
704 
705 PCAP_AVAILABLE_0_4
706 PCAP_API int	pcap_snapshot(pcap_t *);
707 
708 PCAP_AVAILABLE_0_4
709 PCAP_API int	pcap_is_swapped(pcap_t *);
710 
711 PCAP_AVAILABLE_0_4
712 PCAP_API int	pcap_major_version(pcap_t *);
713 
714 PCAP_AVAILABLE_0_4
715 PCAP_API int	pcap_minor_version(pcap_t *);
716 
717 PCAP_AVAILABLE_1_9
718 PCAP_API int	pcap_bufsize(pcap_t *);
719 
720 /* XXX */
721 PCAP_AVAILABLE_0_4
722 PCAP_API FILE	*pcap_file(pcap_t *);
723 
724 #ifdef _WIN32
725 /*
726  * This probably shouldn't have been kept in WinPcap; most if not all
727  * UN*X code that used it won't work on Windows.  We deprecate it; if
728  * anybody really needs access to whatever HANDLE may be associated
729  * with a pcap_t (there's no guarantee that there is one), we can add
730  * a Windows-only pcap_handle() API that returns the HANDLE.
731  */
732 PCAP_AVAILABLE_0_4
733 PCAP_DEPRECATED("request a 'pcap_handle' that returns a HANDLE if you need it")
734 PCAP_API int	pcap_fileno(pcap_t *);
735 #else /* _WIN32 */
736 PCAP_AVAILABLE_0_4
737 PCAP_API int	pcap_fileno(pcap_t *);
738 #endif /* _WIN32 */
739 
740 #ifdef _WIN32
741   PCAP_API int	pcap_wsockinit(void);
742 #endif
743 
744 PCAP_AVAILABLE_0_4
745 PCAP_API pcap_dumper_t *pcap_dump_open(pcap_t *, const char *);
746 
747 #ifdef _WIN32
748   PCAP_AVAILABLE_0_9
749   PCAP_API pcap_dumper_t *pcap_dump_hopen(pcap_t *, intptr_t);
750 
751   /*
752    * If we're building libpcap, this is an internal routine in sf-pcap.c, so
753    * we must not define it as a macro.
754    *
755    * If we're not building libpcap, given that the version of the C runtime
756    * with which libpcap was built might be different from the version
757    * of the C runtime with which an application using libpcap was built,
758    * and that a FILE structure may differ between the two versions of the
759    * C runtime, calls to _fileno() must use the version of _fileno() in
760    * the C runtime used to open the FILE *, not the version in the C
761    * runtime with which libpcap was built.  (Maybe once the Universal CRT
762    * rules the world, this will cease to be a problem.)
763    */
764   #ifndef BUILDING_PCAP
765     #define pcap_dump_fopen(p,f) \
766 	pcap_dump_hopen(p, _get_osfhandle(_fileno(f)))
767   #endif
768 #else /*_WIN32*/
769   PCAP_AVAILABLE_0_9
770   PCAP_API pcap_dumper_t *pcap_dump_fopen(pcap_t *, FILE *fp);
771 #endif /*_WIN32*/
772 
773 PCAP_AVAILABLE_1_7
774 PCAP_API pcap_dumper_t *pcap_dump_open_append(pcap_t *, const char *);
775 
776 PCAP_AVAILABLE_0_8
777 PCAP_API FILE	*pcap_dump_file(pcap_dumper_t *);
778 
779 PCAP_AVAILABLE_0_9
780 PCAP_API long	pcap_dump_ftell(pcap_dumper_t *);
781 
782 PCAP_AVAILABLE_1_9
783 PCAP_API int64_t	pcap_dump_ftell64(pcap_dumper_t *);
784 
785 PCAP_AVAILABLE_0_8
786 PCAP_API int	pcap_dump_flush(pcap_dumper_t *);
787 
788 PCAP_AVAILABLE_0_4
789 PCAP_API void	pcap_dump_close(pcap_dumper_t *);
790 
791 PCAP_AVAILABLE_0_4
792 PCAP_API void	pcap_dump(u_char *, const struct pcap_pkthdr *, const u_char *);
793 
794 PCAP_AVAILABLE_0_7
795 PCAP_API int	pcap_findalldevs(pcap_if_t **, char *);
796 
797 PCAP_AVAILABLE_0_7
798 PCAP_API void	pcap_freealldevs(pcap_if_t *);
799 
800 /*
801  * We return a pointer to the version string, rather than exporting the
802  * version string directly.
803  *
804  * On at least some UNIXes, if you import data from a shared library into
805  * a program, the data is bound into the program binary, so if the string
806  * in the version of the library with which the program was linked isn't
807  * the same as the string in the version of the library with which the
808  * program is being run, various undesirable things may happen (warnings,
809  * the string being the one from the version of the library with which the
810  * program was linked, or even weirder things, such as the string being the
811  * one from the library but being truncated).
812  *
813  * On Windows, the string is constructed at run time.
814  */
815 PCAP_AVAILABLE_0_8
816 PCAP_API const char *pcap_lib_version(void);
817 
818 #if defined(_WIN32)
819 
820   /*
821    * Win32 definitions
822    */
823 
824   /*!
825     \brief A queue of raw packets that will be sent to the network with pcap_sendqueue_transmit().
826   */
827   struct pcap_send_queue
828   {
829 	u_int maxlen;	/* Maximum size of the queue, in bytes. This
830 			   variable contains the size of the buffer field. */
831 	u_int len;	/* Current size of the queue, in bytes. */
832 	char *buffer;	/* Buffer containing the packets to be sent. */
833   };
834 
835   typedef struct pcap_send_queue pcap_send_queue;
836 
837   /*!
838     \brief This typedef is a support for the pcap_get_airpcap_handle() function
839   */
840   #if !defined(AIRPCAP_HANDLE__EAE405F5_0171_9592_B3C2_C19EC426AD34__DEFINED_)
841     #define AIRPCAP_HANDLE__EAE405F5_0171_9592_B3C2_C19EC426AD34__DEFINED_
842     typedef struct _AirpcapHandle *PAirpcapHandle;
843   #endif
844 
845   PCAP_API int pcap_setbuff(pcap_t *p, int dim);
846   PCAP_API int pcap_setmode(pcap_t *p, int mode);
847   PCAP_API int pcap_setmintocopy(pcap_t *p, int size);
848 
849   PCAP_API HANDLE pcap_getevent(pcap_t *p);
850 
851   PCAP_AVAILABLE_1_8
852   PCAP_API int pcap_oid_get_request(pcap_t *, bpf_u_int32, void *, size_t *);
853 
854   PCAP_AVAILABLE_1_8
855   PCAP_API int pcap_oid_set_request(pcap_t *, bpf_u_int32, const void *, size_t *);
856 
857   PCAP_API pcap_send_queue* pcap_sendqueue_alloc(u_int memsize);
858 
859   PCAP_API void pcap_sendqueue_destroy(pcap_send_queue* queue);
860 
861   PCAP_API int pcap_sendqueue_queue(pcap_send_queue* queue, const struct pcap_pkthdr *pkt_header, const u_char *pkt_data);
862 
863   PCAP_API u_int pcap_sendqueue_transmit(pcap_t *p, pcap_send_queue* queue, int sync);
864 
865   PCAP_API struct pcap_stat *pcap_stats_ex(pcap_t *p, int *pcap_stat_size);
866 
867   PCAP_API int pcap_setuserbuffer(pcap_t *p, int size);
868 
869   PCAP_API int pcap_live_dump(pcap_t *p, char *filename, int maxsize, int maxpacks);
870 
871   PCAP_API int pcap_live_dump_ended(pcap_t *p, int sync);
872 
873   PCAP_API int pcap_start_oem(char* err_str, int flags);
874 
875   PCAP_API PAirpcapHandle pcap_get_airpcap_handle(pcap_t *p);
876 
877   #define MODE_CAPT 0
878   #define MODE_STAT 1
879   #define MODE_MON 2
880 
881 #elif defined(MSDOS)
882 
883   /*
884    * MS-DOS definitions
885    */
886 
887   PCAP_API int  pcap_stats_ex (pcap_t *, struct pcap_stat_ex *);
888   PCAP_API void pcap_set_wait (pcap_t *p, void (*yield)(void), int wait);
889   PCAP_API u_long pcap_mac_packets (void);
890 
891 #else /* UN*X */
892 
893   /*
894    * UN*X definitions
895    */
896 
897   PCAP_AVAILABLE_0_8
898   PCAP_API int	pcap_get_selectable_fd(pcap_t *);
899 
900   PCAP_AVAILABLE_1_9
901   PCAP_API const struct timeval *pcap_get_required_select_timeout(pcap_t *);
902 
903 #endif /* _WIN32/MSDOS/UN*X */
904 
905 #if 0	/* Remote capture is disabled on FreeBSD */
906 /*
907  * Remote capture definitions.
908  *
909  * These routines are only present if libpcap has been configured to
910  * include remote capture support.
911  */
912 
913 /*
914  * The maximum buffer size in which address, port, interface names are kept.
915  *
916  * In case the adapter name or such is larger than this value, it is truncated.
917  * This is not used by the user; however it must be aware that an hostname / interface
918  * name longer than this value will be truncated.
919  */
920 #define PCAP_BUF_SIZE 1024
921 
922 /*
923  * The type of input source, passed to pcap_open().
924  */
925 #define PCAP_SRC_FILE		2	/* local savefile */
926 #define PCAP_SRC_IFLOCAL	3	/* local network interface */
927 #define PCAP_SRC_IFREMOTE	4	/* interface on a remote host, using RPCAP */
928 
929 /*
930  * The formats allowed by pcap_open() are the following:
931  * - file://path_and_filename [opens a local file]
932  * - rpcap://devicename [opens the selected device available on the local host, without using the RPCAP protocol]
933  * - rpcap://host/devicename [opens the selected device available on a remote host]
934  * - rpcap://host:port/devicename [opens the selected device available on a remote host, using a non-standard port for RPCAP]
935  * - adaptername [to open a local adapter; kept for compatibility, but it is strongly discouraged]
936  * - (NULL) [to open the first local adapter; kept for compatibility, but it is strongly discouraged]
937  *
938  * The formats allowed by the pcap_findalldevs_ex() are the following:
939  * - file://folder/ [lists all the files in the given folder]
940  * - rpcap:// [lists all local adapters]
941  * - rpcap://host:port/ [lists the devices available on a remote host]
942  *
943  * In all the above, "rpcaps://" can be substituted for "rpcap://" to enable
944  * SSL (if it has been compiled in).
945  *
946  * Referring to the 'host' and 'port' parameters, they can be either numeric or literal. Since
947  * IPv6 is fully supported, these are the allowed formats:
948  *
949  * - host (literal): e.g. host.foo.bar
950  * - host (numeric IPv4): e.g. 10.11.12.13
951  * - host (numeric IPv4, IPv6 style): e.g. [10.11.12.13]
952  * - host (numeric IPv6): e.g. [1:2:3::4]
953  * - port: can be either numeric (e.g. '80') or literal (e.g. 'http')
954  *
955  * Here you find some allowed examples:
956  * - rpcap://host.foo.bar/devicename [everything literal, no port number]
957  * - rpcap://host.foo.bar:1234/devicename [everything literal, with port number]
958  * - rpcap://10.11.12.13/devicename [IPv4 numeric, no port number]
959  * - rpcap://10.11.12.13:1234/devicename [IPv4 numeric, with port number]
960  * - rpcap://[10.11.12.13]:1234/devicename [IPv4 numeric with IPv6 format, with port number]
961  * - rpcap://[1:2:3::4]/devicename [IPv6 numeric, no port number]
962  * - rpcap://[1:2:3::4]:1234/devicename [IPv6 numeric, with port number]
963  * - rpcap://[1:2:3::4]:http/devicename [IPv6 numeric, with literal port number]
964  */
965 
966 /*
967  * URL schemes for capture source.
968  */
969 /*
970  * This string indicates that the user wants to open a capture from a
971  * local file.
972  */
973 #define PCAP_SRC_FILE_STRING "file://"
974 /*
975  * This string indicates that the user wants to open a capture from a
976  * network interface.  This string does not necessarily involve the use
977  * of the RPCAP protocol. If the interface required resides on the local
978  * host, the RPCAP protocol is not involved and the local functions are used.
979  */
980 #define PCAP_SRC_IF_STRING "rpcap://"
981 
982 /*
983  * Flags to pass to pcap_open().
984  */
985 
986 /*
987  * Specifies whether promiscuous mode is to be used.
988  */
989 #define PCAP_OPENFLAG_PROMISCUOUS		0x00000001
990 
991 /*
992  * Specifies, for an RPCAP capture, whether the data transfer (in
993  * case of a remote capture) has to be done with UDP protocol.
994  *
995  * If it is '1' if you want a UDP data connection, '0' if you want
996  * a TCP data connection; control connection is always TCP-based.
997  * A UDP connection is much lighter, but it does not guarantee that all
998  * the captured packets arrive to the client workstation. Moreover,
999  * it could be harmful in case of network congestion.
1000  * This flag is meaningless if the source is not a remote interface.
1001  * In that case, it is simply ignored.
1002  */
1003 #define PCAP_OPENFLAG_DATATX_UDP		0x00000002
1004 
1005 /*
1006  * Specifies whether the remote probe will capture its own generated
1007  * traffic.
1008  *
1009  * In case the remote probe uses the same interface to capture traffic
1010  * and to send data back to the caller, the captured traffic includes
1011  * the RPCAP traffic as well.  If this flag is turned on, the RPCAP
1012  * traffic is excluded from the capture, so that the trace returned
1013  * back to the collector is does not include this traffic.
1014  *
1015  * Has no effect on local interfaces or savefiles.
1016  */
1017 #define PCAP_OPENFLAG_NOCAPTURE_RPCAP		0x00000004
1018 
1019 /*
1020  * Specifies whether the local adapter will capture its own generated traffic.
1021  *
1022  * This flag tells the underlying capture driver to drop the packets
1023  * that were sent by itself.  This is useful when building applications
1024  * such as bridges that should ignore the traffic they just sent.
1025  *
1026  * Supported only on Windows.
1027  */
1028 #define PCAP_OPENFLAG_NOCAPTURE_LOCAL		0x00000008
1029 
1030 /*
1031  * This flag configures the adapter for maximum responsiveness.
1032  *
1033  * In presence of a large value for nbytes, WinPcap waits for the arrival
1034  * of several packets before copying the data to the user. This guarantees
1035  * a low number of system calls, i.e. lower processor usage, i.e. better
1036  * performance, which is good for applications like sniffers. If the user
1037  * sets the PCAP_OPENFLAG_MAX_RESPONSIVENESS flag, the capture driver will
1038  * copy the packets as soon as the application is ready to receive them.
1039  * This is suggested for real time applications (such as, for example,
1040  * a bridge) that need the best responsiveness.
1041  *
1042  * The equivalent with pcap_create()/pcap_activate() is "immediate mode".
1043  */
1044 #define PCAP_OPENFLAG_MAX_RESPONSIVENESS	0x00000010
1045 
1046 /*
1047  * Remote authentication methods.
1048  * These are used in the 'type' member of the pcap_rmtauth structure.
1049  */
1050 
1051 /*
1052  * NULL authentication.
1053  *
1054  * The 'NULL' authentication has to be equal to 'zero', so that old
1055  * applications can just put every field of struct pcap_rmtauth to zero,
1056  * and it does work.
1057  */
1058 #define RPCAP_RMTAUTH_NULL 0
1059 /*
1060  * Username/password authentication.
1061  *
1062  * With this type of authentication, the RPCAP protocol will use the username/
1063  * password provided to authenticate the user on the remote machine. If the
1064  * authentication is successful (and the user has the right to open network
1065  * devices) the RPCAP connection will continue; otherwise it will be dropped.
1066  *
1067  * *******NOTE********: unless TLS is being used, the username and password
1068  * are sent over the network to the capture server *IN CLEAR TEXT*.  Don't
1069  * use this, without TLS (i.e., with rpcap:// rather than rpcaps://) on
1070  * a network that you don't completely control!  (And be *really* careful
1071  * in your definition of "completely"!)
1072  */
1073 #define RPCAP_RMTAUTH_PWD 1
1074 
1075 /*
1076  * This structure keeps the information needed to authenticate the user
1077  * on a remote machine.
1078  *
1079  * The remote machine can either grant or refuse the access according
1080  * to the information provided.
1081  * In case the NULL authentication is required, both 'username' and
1082  * 'password' can be NULL pointers.
1083  *
1084  * This structure is meaningless if the source is not a remote interface;
1085  * in that case, the functions which requires such a structure can accept
1086  * a NULL pointer as well.
1087  */
1088 struct pcap_rmtauth
1089 {
1090 	/*
1091 	 * \brief Type of the authentication required.
1092 	 *
1093 	 * In order to provide maximum flexibility, we can support different types
1094 	 * of authentication based on the value of this 'type' variable. The currently
1095 	 * supported authentication methods are defined into the
1096 	 * \link remote_auth_methods Remote Authentication Methods Section\endlink.
1097 	 */
1098 	int type;
1099 	/*
1100 	 * \brief Zero-terminated string containing the username that has to be
1101 	 * used on the remote machine for authentication.
1102 	 *
1103 	 * This field is meaningless in case of the RPCAP_RMTAUTH_NULL authentication
1104 	 * and it can be NULL.
1105 	 */
1106 	char *username;
1107 	/*
1108 	 * \brief Zero-terminated string containing the password that has to be
1109 	 * used on the remote machine for authentication.
1110 	 *
1111 	 * This field is meaningless in case of the RPCAP_RMTAUTH_NULL authentication
1112 	 * and it can be NULL.
1113 	 */
1114 	char *password;
1115 };
1116 
1117 /*
1118  * This routine can open a savefile, a local device, or a device on
1119  * a remote machine running an RPCAP server.
1120  *
1121  * For opening a savefile, the pcap_open_offline routines can be used,
1122  * and will work just as well; code using them will work on more
1123  * platforms than code using pcap_open() to open savefiles.
1124  *
1125  * For opening a local device, pcap_open_live() can be used; it supports
1126  * most of the capabilities that pcap_open() supports, and code using it
1127  * will work on more platforms than code using pcap_open().  pcap_create()
1128  * and pcap_activate() can also be used; they support all capabilities
1129  * that pcap_open() supports, except for the Windows-only
1130  * PCAP_OPENFLAG_NOCAPTURE_LOCAL, and support additional capabilities.
1131  *
1132  * For opening a remote capture, pcap_open() is currently the only
1133  * API available.
1134  */
1135 PCAP_AVAILABLE_1_9_REMOTE
1136 PCAP_API pcap_t	*pcap_open(const char *source, int snaplen, int flags,
1137 	    int read_timeout, struct pcap_rmtauth *auth, char *errbuf);
1138 
1139 PCAP_AVAILABLE_1_9_REMOTE
1140 PCAP_API int	pcap_createsrcstr(char *source, int type, const char *host,
1141 	    const char *port, const char *name, char *errbuf);
1142 
1143 PCAP_AVAILABLE_1_9_REMOTE
1144 PCAP_API int	pcap_parsesrcstr(const char *source, int *type, char *host,
1145 	    char *port, char *name, char *errbuf);
1146 
1147 /*
1148  * This routine can scan a directory for savefiles, list local capture
1149  * devices, or list capture devices on a remote machine running an RPCAP
1150  * server.
1151  *
1152  * For scanning for savefiles, it can be used on both UN*X systems and
1153  * Windows systems; for each directory entry it sees, it tries to open
1154  * the file as a savefile using pcap_open_offline(), and only includes
1155  * it in the list of files if the open succeeds, so it filters out
1156  * files for which the user doesn't have read permission, as well as
1157  * files that aren't valid savefiles readable by libpcap.
1158  *
1159  * For listing local capture devices, it's just a wrapper around
1160  * pcap_findalldevs(); code using pcap_findalldevs() will work on more
1161  * platforms than code using pcap_findalldevs_ex().
1162  *
1163  * For listing remote capture devices, pcap_findalldevs_ex() is currently
1164  * the only API available.
1165  */
1166 PCAP_AVAILABLE_1_9_REMOTE
1167 PCAP_API int	pcap_findalldevs_ex(const char *source,
1168 	    struct pcap_rmtauth *auth, pcap_if_t **alldevs, char *errbuf);
1169 
1170 /*
1171  * Sampling methods.
1172  *
1173  * These allow pcap_loop(), pcap_dispatch(), pcap_next(), and pcap_next_ex()
1174  * to see only a sample of packets, rather than all packets.
1175  *
1176  * Currently, they work only on Windows local captures.
1177  */
1178 
1179 /*
1180  * Specifies that no sampling is to be done on the current capture.
1181  *
1182  * In this case, no sampling algorithms are applied to the current capture.
1183  */
1184 #define PCAP_SAMP_NOSAMP	0
1185 
1186 /*
1187  * Specifies that only 1 out of N packets must be returned to the user.
1188  *
1189  * In this case, the 'value' field of the 'pcap_samp' structure indicates the
1190  * number of packets (minus 1) that must be discarded before one packet got
1191  * accepted.
1192  * In other words, if 'value = 10', the first packet is returned to the
1193  * caller, while the following 9 are discarded.
1194  */
1195 #define PCAP_SAMP_1_EVERY_N	1
1196 
1197 /*
1198  * Specifies that we have to return 1 packet every N milliseconds.
1199  *
1200  * In this case, the 'value' field of the 'pcap_samp' structure indicates
1201  * the 'waiting time' in milliseconds before one packet got accepted.
1202  * In other words, if 'value = 10', the first packet is returned to the
1203  * caller; the next returned one will be the first packet that arrives
1204  * when 10ms have elapsed.
1205  */
1206 #define PCAP_SAMP_FIRST_AFTER_N_MS 2
1207 
1208 /*
1209  * This structure defines the information related to sampling.
1210  *
1211  * In case the sampling is requested, the capturing device should read
1212  * only a subset of the packets coming from the source. The returned packets
1213  * depend on the sampling parameters.
1214  *
1215  * WARNING: The sampling process is applied *after* the filtering process.
1216  * In other words, packets are filtered first, then the sampling process
1217  * selects a subset of the 'filtered' packets and it returns them to the
1218  * caller.
1219  */
1220 struct pcap_samp
1221 {
1222 	/*
1223 	 * Method used for sampling; see above.
1224 	 */
1225 	int method;
1226 
1227 	/*
1228 	 * This value depends on the sampling method defined.
1229 	 * For its meaning, see above.
1230 	 */
1231 	int value;
1232 };
1233 
1234 /*
1235  * New functions.
1236  */
1237 PCAP_AVAILABLE_1_9_REMOTE
1238 PCAP_API struct pcap_samp *pcap_setsampling(pcap_t *p);
1239 
1240 /*
1241  * RPCAP active mode.
1242  */
1243 
1244 /* Maximum length of an host name (needed for the RPCAP active mode) */
1245 #define RPCAP_HOSTLIST_SIZE 1024
1246 
1247 PCAP_AVAILABLE_1_9_REMOTE
1248 PCAP_API PCAP_SOCKET	pcap_remoteact_accept(const char *address, const char *port,
1249 	    const char *hostlist, char *connectinghost,
1250 	    struct pcap_rmtauth *auth, char *errbuf);
1251 
1252 PCAP_AVAILABLE_1_10_REMOTE
1253 PCAP_API PCAP_SOCKET	pcap_remoteact_accept_ex(const char *address, const char *port,
1254 	    const char *hostlist, char *connectinghost,
1255 	    struct pcap_rmtauth *auth, int uses_ssl, char *errbuf);
1256 
1257 PCAP_AVAILABLE_1_9_REMOTE
1258 PCAP_API int	pcap_remoteact_list(char *hostlist, char sep, int size,
1259 	    char *errbuf);
1260 
1261 PCAP_AVAILABLE_1_9_REMOTE
1262 PCAP_API int	pcap_remoteact_close(const char *host, char *errbuf);
1263 
1264 PCAP_AVAILABLE_1_9_REMOTE
1265 PCAP_API void	pcap_remoteact_cleanup(void);
1266 #endif	/* Remote capture is disabled on FreeBSD */
1267 
1268 #ifdef __cplusplus
1269 }
1270 #endif
1271 
1272 #endif /* lib_pcap_pcap_h */
1273