xref: /freebsd/contrib/libpcap/pcap/pcap.h (revision 445ed7b40948c160f2f7d363d2d0ae1ffac4aabd)
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  * @(#) $Header: /tcpdump/master/libpcap/pcap/pcap.h,v 1.15 2008-10-06 15:27:32 gianluca Exp $ (LBL)
35  */
36 
37 #ifndef lib_pcap_pcap_h
38 #define lib_pcap_pcap_h
39 
40 #if defined(WIN32)
41   #include <pcap-stdinc.h>
42 #elif defined(MSDOS)
43   #include <sys/types.h>
44   #include <sys/socket.h>  /* u_int, u_char etc. */
45 #else /* UN*X */
46   #include <sys/types.h>
47   #include <sys/time.h>
48 #endif /* WIN32/MSDOS/UN*X */
49 
50 #include <net/bpf.h>
51 
52 #include <stdio.h>
53 
54 #ifdef __cplusplus
55 extern "C" {
56 #endif
57 
58 /*
59  * Version number of the current version of the pcap file format.
60  *
61  * NOTE: this is *NOT* the version number of the libpcap library.
62  * To fetch the version information for the version of libpcap
63  * you're using, use pcap_lib_version().
64  */
65 #define PCAP_VERSION_MAJOR 2
66 #define PCAP_VERSION_MINOR 4
67 
68 #define PCAP_ERRBUF_SIZE 256
69 
70 /*
71  * Compatibility for systems that have a bpf.h that
72  * predates the bpf typedefs for 64-bit support.
73  */
74 #if BPF_RELEASE - 0 < 199406
75 typedef	int bpf_int32;
76 typedef	u_int bpf_u_int32;
77 #endif
78 
79 typedef struct pcap pcap_t;
80 typedef struct pcap_dumper pcap_dumper_t;
81 typedef struct pcap_if pcap_if_t;
82 typedef struct pcap_addr pcap_addr_t;
83 
84 /*
85  * The first record in the file contains saved values for some
86  * of the flags used in the printout phases of tcpdump.
87  * Many fields here are 32 bit ints so compilers won't insert unwanted
88  * padding; these files need to be interchangeable across architectures.
89  *
90  * Do not change the layout of this structure, in any way (this includes
91  * changes that only affect the length of fields in this structure).
92  *
93  * Also, do not change the interpretation of any of the members of this
94  * structure, in any way (this includes using values other than
95  * LINKTYPE_ values, as defined in "savefile.c", in the "linktype"
96  * field).
97  *
98  * Instead:
99  *
100  *	introduce a new structure for the new format, if the layout
101  *	of the structure changed;
102  *
103  *	send mail to "tcpdump-workers@lists.tcpdump.org", requesting
104  *	a new magic number for your new capture file format, and, when
105  *	you get the new magic number, put it in "savefile.c";
106  *
107  *	use that magic number for save files with the changed file
108  *	header;
109  *
110  *	make the code in "savefile.c" capable of reading files with
111  *	the old file header as well as files with the new file header
112  *	(using the magic number to determine the header format).
113  *
114  * Then supply the changes by forking the branch at
115  *
116  *	https://github.com/mcr/libpcap/issues
117  *
118  * and issuing a pull request, so that future versions of libpcap and
119  * programs that use it (such as tcpdump) will be able to read your new
120  * capture file format.
121  */
122 struct pcap_file_header {
123 	bpf_u_int32 magic;
124 	u_short version_major;
125 	u_short version_minor;
126 	bpf_int32 thiszone;	/* gmt to local correction */
127 	bpf_u_int32 sigfigs;	/* accuracy of timestamps */
128 	bpf_u_int32 snaplen;	/* max length saved portion of each pkt */
129 	bpf_u_int32 linktype;	/* data link type (LINKTYPE_*) */
130 };
131 
132 /*
133  * Macros for the value returned by pcap_datalink_ext().
134  *
135  * If LT_FCS_LENGTH_PRESENT(x) is true, the LT_FCS_LENGTH(x) macro
136  * gives the FCS length of packets in the capture.
137  */
138 #define LT_FCS_LENGTH_PRESENT(x)	((x) & 0x04000000)
139 #define LT_FCS_LENGTH(x)		(((x) & 0xF0000000) >> 28)
140 #define LT_FCS_DATALINK_EXT(x)		((((x) & 0xF) << 28) | 0x04000000)
141 
142 typedef enum {
143        PCAP_D_INOUT = 0,
144        PCAP_D_IN,
145        PCAP_D_OUT
146 } pcap_direction_t;
147 
148 /*
149  * Generic per-packet information, as supplied by libpcap.
150  *
151  * The time stamp can and should be a "struct timeval", regardless of
152  * whether your system supports 32-bit tv_sec in "struct timeval",
153  * 64-bit tv_sec in "struct timeval", or both if it supports both 32-bit
154  * and 64-bit applications.  The on-disk format of savefiles uses 32-bit
155  * tv_sec (and tv_usec); this structure is irrelevant to that.  32-bit
156  * and 64-bit versions of libpcap, even if they're on the same platform,
157  * should supply the appropriate version of "struct timeval", even if
158  * that's not what the underlying packet capture mechanism supplies.
159  */
160 struct pcap_pkthdr {
161 	struct timeval ts;	/* time stamp */
162 	bpf_u_int32 caplen;	/* length of portion present */
163 	bpf_u_int32 len;	/* length this packet (off wire) */
164 };
165 
166 /*
167  * As returned by the pcap_stats()
168  */
169 struct pcap_stat {
170 	u_int ps_recv;		/* number of packets received */
171 	u_int ps_drop;		/* number of packets dropped */
172 	u_int ps_ifdrop;	/* drops by interface -- only supported on some platforms */
173 #ifdef WIN32
174 	u_int bs_capt;		/* number of packets that reach the application */
175 #endif /* WIN32 */
176 };
177 
178 #ifdef MSDOS
179 /*
180  * As returned by the pcap_stats_ex()
181  */
182 struct pcap_stat_ex {
183        u_long  rx_packets;        /* total packets received       */
184        u_long  tx_packets;        /* total packets transmitted    */
185        u_long  rx_bytes;          /* total bytes received         */
186        u_long  tx_bytes;          /* total bytes transmitted      */
187        u_long  rx_errors;         /* bad packets received         */
188        u_long  tx_errors;         /* packet transmit problems     */
189        u_long  rx_dropped;        /* no space in Rx buffers       */
190        u_long  tx_dropped;        /* no space available for Tx    */
191        u_long  multicast;         /* multicast packets received   */
192        u_long  collisions;
193 
194        /* detailed rx_errors: */
195        u_long  rx_length_errors;
196        u_long  rx_over_errors;    /* receiver ring buff overflow  */
197        u_long  rx_crc_errors;     /* recv'd pkt with crc error    */
198        u_long  rx_frame_errors;   /* recv'd frame alignment error */
199        u_long  rx_fifo_errors;    /* recv'r fifo overrun          */
200        u_long  rx_missed_errors;  /* recv'r missed packet         */
201 
202        /* detailed tx_errors */
203        u_long  tx_aborted_errors;
204        u_long  tx_carrier_errors;
205        u_long  tx_fifo_errors;
206        u_long  tx_heartbeat_errors;
207        u_long  tx_window_errors;
208      };
209 #endif
210 
211 /*
212  * Item in a list of interfaces.
213  */
214 struct pcap_if {
215 	struct pcap_if *next;
216 	char *name;		/* name to hand to "pcap_open_live()" */
217 	char *description;	/* textual description of interface, or NULL */
218 	struct pcap_addr *addresses;
219 	bpf_u_int32 flags;	/* PCAP_IF_ interface flags */
220 };
221 
222 #define PCAP_IF_LOOPBACK	0x00000001	/* interface is loopback */
223 
224 /*
225  * Representation of an interface address.
226  */
227 struct pcap_addr {
228 	struct pcap_addr *next;
229 	struct sockaddr *addr;		/* address */
230 	struct sockaddr *netmask;	/* netmask for that address */
231 	struct sockaddr *broadaddr;	/* broadcast address for that address */
232 	struct sockaddr *dstaddr;	/* P2P destination address for that address */
233 };
234 
235 typedef void (*pcap_handler)(u_char *, const struct pcap_pkthdr *,
236 			     const u_char *);
237 
238 /*
239  * Error codes for the pcap API.
240  * These will all be negative, so you can check for the success or
241  * failure of a call that returns these codes by checking for a
242  * negative value.
243  */
244 #define PCAP_ERROR			-1	/* generic error code */
245 #define PCAP_ERROR_BREAK		-2	/* loop terminated by pcap_breakloop */
246 #define PCAP_ERROR_NOT_ACTIVATED	-3	/* the capture needs to be activated */
247 #define PCAP_ERROR_ACTIVATED		-4	/* the operation can't be performed on already activated captures */
248 #define PCAP_ERROR_NO_SUCH_DEVICE	-5	/* no such device exists */
249 #define PCAP_ERROR_RFMON_NOTSUP		-6	/* this device doesn't support rfmon (monitor) mode */
250 #define PCAP_ERROR_NOT_RFMON		-7	/* operation supported only in monitor mode */
251 #define PCAP_ERROR_PERM_DENIED		-8	/* no permission to open the device */
252 #define PCAP_ERROR_IFACE_NOT_UP		-9	/* interface isn't up */
253 #define PCAP_ERROR_CANTSET_TSTAMP_TYPE	-10	/* this device doesn't support setting the time stamp type */
254 #define PCAP_ERROR_PROMISC_PERM_DENIED	-11	/* you don't have permission to capture in promiscuous mode */
255 
256 /*
257  * Warning codes for the pcap API.
258  * These will all be positive and non-zero, so they won't look like
259  * errors.
260  */
261 #define PCAP_WARNING			1	/* generic warning code */
262 #define PCAP_WARNING_PROMISC_NOTSUP	2	/* this device doesn't support promiscuous mode */
263 #define PCAP_WARNING_TSTAMP_TYPE_NOTSUP	3	/* the requested time stamp type is not supported */
264 
265 /*
266  * Value to pass to pcap_compile() as the netmask if you don't know what
267  * the netmask is.
268  */
269 #define PCAP_NETMASK_UNKNOWN	0xffffffff
270 
271 char	*pcap_lookupdev(char *);
272 int	pcap_lookupnet(const char *, bpf_u_int32 *, bpf_u_int32 *, char *);
273 
274 pcap_t	*pcap_create(const char *, char *);
275 int	pcap_set_snaplen(pcap_t *, int);
276 int	pcap_set_promisc(pcap_t *, int);
277 int	pcap_can_set_rfmon(pcap_t *);
278 int	pcap_set_rfmon(pcap_t *, int);
279 int	pcap_set_timeout(pcap_t *, int);
280 int	pcap_set_tstamp_type(pcap_t *, int);
281 int	pcap_set_buffer_size(pcap_t *, int);
282 int	pcap_activate(pcap_t *);
283 
284 int	pcap_list_tstamp_types(pcap_t *, int **);
285 void	pcap_free_tstamp_types(int *);
286 int	pcap_tstamp_type_name_to_val(const char *);
287 const char *pcap_tstamp_type_val_to_name(int);
288 const char *pcap_tstamp_type_val_to_description(int);
289 
290 /*
291  * Time stamp types.
292  * Not all systems and interfaces will necessarily support all of these.
293  *
294  * A system that supports PCAP_TSTAMP_HOST is offering time stamps
295  * provided by the host machine, rather than by the capture device,
296  * but not committing to any characteristics of the time stamp;
297  * it will not offer any of the PCAP_TSTAMP_HOST_ subtypes.
298  *
299  * PCAP_TSTAMP_HOST_LOWPREC is a time stamp, provided by the host machine,
300  * that's low-precision but relatively cheap to fetch; it's normally done
301  * using the system clock, so it's normally synchronized with times you'd
302  * fetch from system calls.
303  *
304  * PCAP_TSTAMP_HOST_HIPREC is a time stamp, provided by the host machine,
305  * that's high-precision; it might be more expensive to fetch.  It might
306  * or might not be synchronized with the system clock, and might have
307  * problems with time stamps for packets received on different CPUs,
308  * depending on the platform.
309  *
310  * PCAP_TSTAMP_ADAPTER is a high-precision time stamp supplied by the
311  * capture device; it's synchronized with the system clock.
312  *
313  * PCAP_TSTAMP_ADAPTER_UNSYNCED is a high-precision time stamp supplied by
314  * the capture device; it's not synchronized with the system clock.
315  *
316  * Note that time stamps synchronized with the system clock can go
317  * backwards, as the system clock can go backwards.  If a clock is
318  * not in sync with the system clock, that could be because the
319  * system clock isn't keeping accurate time, because the other
320  * clock isn't keeping accurate time, or both.
321  *
322  * Note that host-provided time stamps generally correspond to the
323  * time when the time-stamping code sees the packet; this could
324  * be some unknown amount of time after the first or last bit of
325  * the packet is received by the network adapter, due to batching
326  * of interrupts for packet arrival, queueing delays, etc..
327  */
328 #define PCAP_TSTAMP_HOST		0	/* host-provided, unknown characteristics */
329 #define PCAP_TSTAMP_HOST_LOWPREC	1	/* host-provided, low precision */
330 #define PCAP_TSTAMP_HOST_HIPREC		2	/* host-provided, high precision */
331 #define PCAP_TSTAMP_ADAPTER		3	/* device-provided, synced with the system clock */
332 #define PCAP_TSTAMP_ADAPTER_UNSYNCED	4	/* device-provided, not synced with the system clock */
333 
334 pcap_t	*pcap_open_live(const char *, int, int, int, char *);
335 pcap_t	*pcap_open_dead(int, int);
336 pcap_t	*pcap_open_offline(const char *, char *);
337 #if defined(WIN32)
338 pcap_t  *pcap_hopen_offline(intptr_t, char *);
339 #if !defined(LIBPCAP_EXPORTS)
340 #define pcap_fopen_offline(f,b) \
341 	pcap_hopen_offline(_get_osfhandle(_fileno(f)), b)
342 #else /*LIBPCAP_EXPORTS*/
343 static pcap_t *pcap_fopen_offline(FILE *, char *);
344 #endif
345 #else /*WIN32*/
346 pcap_t	*pcap_fopen_offline(FILE *, char *);
347 #endif /*WIN32*/
348 
349 void	pcap_close(pcap_t *);
350 int	pcap_loop(pcap_t *, int, pcap_handler, u_char *);
351 int	pcap_dispatch(pcap_t *, int, pcap_handler, u_char *);
352 const u_char*
353 	pcap_next(pcap_t *, struct pcap_pkthdr *);
354 int 	pcap_next_ex(pcap_t *, struct pcap_pkthdr **, const u_char **);
355 void	pcap_breakloop(pcap_t *);
356 int	pcap_stats(pcap_t *, struct pcap_stat *);
357 int	pcap_setfilter(pcap_t *, struct bpf_program *);
358 int 	pcap_setdirection(pcap_t *, pcap_direction_t);
359 int	pcap_getnonblock(pcap_t *, char *);
360 int	pcap_setnonblock(pcap_t *, int, char *);
361 int	pcap_inject(pcap_t *, const void *, size_t);
362 int	pcap_sendpacket(pcap_t *, const u_char *, int);
363 const char *pcap_statustostr(int);
364 const char *pcap_strerror(int);
365 char	*pcap_geterr(pcap_t *);
366 void	pcap_perror(pcap_t *, char *);
367 int	pcap_compile(pcap_t *, struct bpf_program *, const char *, int,
368 	    bpf_u_int32);
369 int	pcap_compile_nopcap(int, int, struct bpf_program *,
370 	    const char *, int, bpf_u_int32);
371 void	pcap_freecode(struct bpf_program *);
372 int	pcap_offline_filter(const struct bpf_program *,
373 	    const struct pcap_pkthdr *, const u_char *);
374 int	pcap_datalink(pcap_t *);
375 int	pcap_datalink_ext(pcap_t *);
376 int	pcap_list_datalinks(pcap_t *, int **);
377 int	pcap_set_datalink(pcap_t *, int);
378 void	pcap_free_datalinks(int *);
379 int	pcap_datalink_name_to_val(const char *);
380 const char *pcap_datalink_val_to_name(int);
381 const char *pcap_datalink_val_to_description(int);
382 int	pcap_snapshot(pcap_t *);
383 int	pcap_is_swapped(pcap_t *);
384 int	pcap_major_version(pcap_t *);
385 int	pcap_minor_version(pcap_t *);
386 
387 /* XXX */
388 FILE	*pcap_file(pcap_t *);
389 int	pcap_fileno(pcap_t *);
390 
391 pcap_dumper_t *pcap_dump_open(pcap_t *, const char *);
392 pcap_dumper_t *pcap_dump_fopen(pcap_t *, FILE *fp);
393 FILE	*pcap_dump_file(pcap_dumper_t *);
394 long	pcap_dump_ftell(pcap_dumper_t *);
395 int	pcap_dump_flush(pcap_dumper_t *);
396 void	pcap_dump_close(pcap_dumper_t *);
397 void	pcap_dump(u_char *, const struct pcap_pkthdr *, const u_char *);
398 
399 int	pcap_findalldevs(pcap_if_t **, char *);
400 void	pcap_freealldevs(pcap_if_t *);
401 
402 const char *pcap_lib_version(void);
403 
404 /*
405  * On at least some versions of NetBSD, we don't want to declare
406  * bpf_filter() here, as it's also be declared in <net/bpf.h>, with a
407  * different signature, but, on other BSD-flavored UN*Xes, it's not
408  * declared in <net/bpf.h>, so we *do* want to declare it here, so it's
409  * declared when we build pcap-bpf.c.
410  */
411 #ifndef __NetBSD__
412 u_int	bpf_filter(const struct bpf_insn *, const u_char *, u_int, u_int);
413 #endif
414 int	bpf_validate(const struct bpf_insn *f, int len);
415 char	*bpf_image(const struct bpf_insn *, int);
416 void	bpf_dump(const struct bpf_program *, int);
417 
418 #if defined(WIN32)
419 
420 /*
421  * Win32 definitions
422  */
423 
424 int pcap_setbuff(pcap_t *p, int dim);
425 int pcap_setmode(pcap_t *p, int mode);
426 int pcap_setmintocopy(pcap_t *p, int size);
427 
428 #ifdef WPCAP
429 /* Include file with the wpcap-specific extensions */
430 #include <Win32-Extensions.h>
431 #endif /* WPCAP */
432 
433 #define MODE_CAPT 0
434 #define MODE_STAT 1
435 #define MODE_MON 2
436 
437 #elif defined(MSDOS)
438 
439 /*
440  * MS-DOS definitions
441  */
442 
443 int  pcap_stats_ex (pcap_t *, struct pcap_stat_ex *);
444 void pcap_set_wait (pcap_t *p, void (*yield)(void), int wait);
445 u_long pcap_mac_packets (void);
446 
447 #else /* UN*X */
448 
449 /*
450  * UN*X definitions
451  */
452 
453 int	pcap_get_selectable_fd(pcap_t *);
454 
455 #endif /* WIN32/MSDOS/UN*X */
456 
457 #ifdef __cplusplus
458 }
459 #endif
460 
461 #endif /* lib_pcap_pcap_h */
462