xref: /freebsd/contrib/libpcap/pcap/pcap.h (revision bc96366c864c07ef352edb92017357917c75b36c)
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 #ifndef lib_pcap_pcap_h
36 #define lib_pcap_pcap_h
37 
38 #if defined(WIN32)
39   #include <pcap-stdinc.h>
40 #elif defined(MSDOS)
41   #include <sys/types.h>
42   #include <sys/socket.h>  /* u_int, u_char etc. */
43 #else /* UN*X */
44   #include <sys/types.h>
45   #include <sys/time.h>
46 #endif /* WIN32/MSDOS/UN*X */
47 
48 #include <net/bpf.h>
49 
50 #include <stdio.h>
51 
52 #ifdef __cplusplus
53 extern "C" {
54 #endif
55 
56 /*
57  * Version number of the current version of the pcap file format.
58  *
59  * NOTE: this is *NOT* the version number of the libpcap library.
60  * To fetch the version information for the version of libpcap
61  * you're using, use pcap_lib_version().
62  */
63 #define PCAP_VERSION_MAJOR 2
64 #define PCAP_VERSION_MINOR 4
65 
66 #define PCAP_ERRBUF_SIZE 256
67 
68 /*
69  * Compatibility for systems that have a bpf.h that
70  * predates the bpf typedefs for 64-bit support.
71  */
72 #if BPF_RELEASE - 0 < 199406
73 typedef	int bpf_int32;
74 typedef	u_int bpf_u_int32;
75 #endif
76 
77 typedef struct pcap pcap_t;
78 typedef struct pcap_dumper pcap_dumper_t;
79 typedef struct pcap_if pcap_if_t;
80 typedef struct pcap_addr pcap_addr_t;
81 
82 /*
83  * The first record in the file contains saved values for some
84  * of the flags used in the printout phases of tcpdump.
85  * Many fields here are 32 bit ints so compilers won't insert unwanted
86  * padding; these files need to be interchangeable across architectures.
87  *
88  * Do not change the layout of this structure, in any way (this includes
89  * changes that only affect the length of fields in this structure).
90  *
91  * Also, do not change the interpretation of any of the members of this
92  * structure, in any way (this includes using values other than
93  * LINKTYPE_ values, as defined in "savefile.c", in the "linktype"
94  * field).
95  *
96  * Instead:
97  *
98  *	introduce a new structure for the new format, if the layout
99  *	of the structure changed;
100  *
101  *	send mail to "tcpdump-workers@lists.tcpdump.org", requesting
102  *	a new magic number for your new capture file format, and, when
103  *	you get the new magic number, put it in "savefile.c";
104  *
105  *	use that magic number for save files with the changed file
106  *	header;
107  *
108  *	make the code in "savefile.c" capable of reading files with
109  *	the old file header as well as files with the new file header
110  *	(using the magic number to determine the header format).
111  *
112  * Then supply the changes by forking the branch at
113  *
114  *	https://github.com/the-tcpdump-group/libpcap/issues
115  *
116  * and issuing a pull request, so that future versions of libpcap and
117  * programs that use it (such as tcpdump) will be able to read your new
118  * capture file format.
119  */
120 struct pcap_file_header {
121 	bpf_u_int32 magic;
122 	u_short version_major;
123 	u_short version_minor;
124 	bpf_int32 thiszone;	/* gmt to local correction */
125 	bpf_u_int32 sigfigs;	/* accuracy of timestamps */
126 	bpf_u_int32 snaplen;	/* max length saved portion of each pkt */
127 	bpf_u_int32 linktype;	/* data link type (LINKTYPE_*) */
128 };
129 
130 /*
131  * Macros for the value returned by pcap_datalink_ext().
132  *
133  * If LT_FCS_LENGTH_PRESENT(x) is true, the LT_FCS_LENGTH(x) macro
134  * gives the FCS length of packets in the capture.
135  */
136 #define LT_FCS_LENGTH_PRESENT(x)	((x) & 0x04000000)
137 #define LT_FCS_LENGTH(x)		(((x) & 0xF0000000) >> 28)
138 #define LT_FCS_DATALINK_EXT(x)		((((x) & 0xF) << 28) | 0x04000000)
139 
140 typedef enum {
141        PCAP_D_INOUT = 0,
142        PCAP_D_IN,
143        PCAP_D_OUT
144 } pcap_direction_t;
145 
146 /*
147  * Generic per-packet information, as supplied by libpcap.
148  *
149  * The time stamp can and should be a "struct timeval", regardless of
150  * whether your system supports 32-bit tv_sec in "struct timeval",
151  * 64-bit tv_sec in "struct timeval", or both if it supports both 32-bit
152  * and 64-bit applications.  The on-disk format of savefiles uses 32-bit
153  * tv_sec (and tv_usec); this structure is irrelevant to that.  32-bit
154  * and 64-bit versions of libpcap, even if they're on the same platform,
155  * should supply the appropriate version of "struct timeval", even if
156  * that's not what the underlying packet capture mechanism supplies.
157  */
158 struct pcap_pkthdr {
159 	struct timeval ts;	/* time stamp */
160 	bpf_u_int32 caplen;	/* length of portion present */
161 	bpf_u_int32 len;	/* length this packet (off wire) */
162 };
163 
164 /*
165  * As returned by the pcap_stats()
166  */
167 struct pcap_stat {
168 	u_int ps_recv;		/* number of packets received */
169 	u_int ps_drop;		/* number of packets dropped */
170 	u_int ps_ifdrop;	/* drops by interface -- only supported on some platforms */
171 #ifdef WIN32
172 	u_int bs_capt;		/* number of packets that reach the application */
173 #endif /* WIN32 */
174 };
175 
176 #ifdef MSDOS
177 /*
178  * As returned by the pcap_stats_ex()
179  */
180 struct pcap_stat_ex {
181        u_long  rx_packets;        /* total packets received       */
182        u_long  tx_packets;        /* total packets transmitted    */
183        u_long  rx_bytes;          /* total bytes received         */
184        u_long  tx_bytes;          /* total bytes transmitted      */
185        u_long  rx_errors;         /* bad packets received         */
186        u_long  tx_errors;         /* packet transmit problems     */
187        u_long  rx_dropped;        /* no space in Rx buffers       */
188        u_long  tx_dropped;        /* no space available for Tx    */
189        u_long  multicast;         /* multicast packets received   */
190        u_long  collisions;
191 
192        /* detailed rx_errors: */
193        u_long  rx_length_errors;
194        u_long  rx_over_errors;    /* receiver ring buff overflow  */
195        u_long  rx_crc_errors;     /* recv'd pkt with crc error    */
196        u_long  rx_frame_errors;   /* recv'd frame alignment error */
197        u_long  rx_fifo_errors;    /* recv'r fifo overrun          */
198        u_long  rx_missed_errors;  /* recv'r missed packet         */
199 
200        /* detailed tx_errors */
201        u_long  tx_aborted_errors;
202        u_long  tx_carrier_errors;
203        u_long  tx_fifo_errors;
204        u_long  tx_heartbeat_errors;
205        u_long  tx_window_errors;
206      };
207 #endif
208 
209 /*
210  * Item in a list of interfaces.
211  */
212 struct pcap_if {
213 	struct pcap_if *next;
214 	char *name;		/* name to hand to "pcap_open_live()" */
215 	char *description;	/* textual description of interface, or NULL */
216 	struct pcap_addr *addresses;
217 	bpf_u_int32 flags;	/* PCAP_IF_ interface flags */
218 };
219 
220 #define PCAP_IF_LOOPBACK	0x00000001	/* interface is loopback */
221 #define PCAP_IF_UP		0x00000002	/* interface is up */
222 #define PCAP_IF_RUNNING		0x00000004	/* interface is running */
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 #define PCAP_ERROR_TSTAMP_PRECISION_NOTSUP -12  /* the requested time stamp precision is not supported */
256 
257 /*
258  * Warning codes for the pcap API.
259  * These will all be positive and non-zero, so they won't look like
260  * errors.
261  */
262 #define PCAP_WARNING			1	/* generic warning code */
263 #define PCAP_WARNING_PROMISC_NOTSUP	2	/* this device doesn't support promiscuous mode */
264 #define PCAP_WARNING_TSTAMP_TYPE_NOTSUP	3	/* the requested time stamp type is not supported */
265 
266 /*
267  * Value to pass to pcap_compile() as the netmask if you don't know what
268  * the netmask is.
269  */
270 #define PCAP_NETMASK_UNKNOWN	0xffffffff
271 
272 char	*pcap_lookupdev(char *);
273 int	pcap_lookupnet(const char *, bpf_u_int32 *, bpf_u_int32 *, char *);
274 
275 pcap_t	*pcap_create(const char *, char *);
276 int	pcap_set_snaplen(pcap_t *, int);
277 int	pcap_set_promisc(pcap_t *, int);
278 int	pcap_can_set_rfmon(pcap_t *);
279 int	pcap_set_rfmon(pcap_t *, int);
280 int	pcap_set_timeout(pcap_t *, int);
281 int	pcap_set_tstamp_type(pcap_t *, int);
282 int	pcap_set_immediate_mode(pcap_t *, int);
283 int	pcap_set_buffer_size(pcap_t *, int);
284 int	pcap_set_tstamp_precision(pcap_t *, int);
285 int	pcap_get_tstamp_precision(pcap_t *);
286 int	pcap_activate(pcap_t *);
287 
288 int	pcap_list_tstamp_types(pcap_t *, int **);
289 void	pcap_free_tstamp_types(int *);
290 int	pcap_tstamp_type_name_to_val(const char *);
291 const char *pcap_tstamp_type_val_to_name(int);
292 const char *pcap_tstamp_type_val_to_description(int);
293 
294 /*
295  * Time stamp types.
296  * Not all systems and interfaces will necessarily support all of these.
297  *
298  * A system that supports PCAP_TSTAMP_HOST is offering time stamps
299  * provided by the host machine, rather than by the capture device,
300  * but not committing to any characteristics of the time stamp;
301  * it will not offer any of the PCAP_TSTAMP_HOST_ subtypes.
302  *
303  * PCAP_TSTAMP_HOST_LOWPREC is a time stamp, provided by the host machine,
304  * that's low-precision but relatively cheap to fetch; it's normally done
305  * using the system clock, so it's normally synchronized with times you'd
306  * fetch from system calls.
307  *
308  * PCAP_TSTAMP_HOST_HIPREC is a time stamp, provided by the host machine,
309  * that's high-precision; it might be more expensive to fetch.  It might
310  * or might not be synchronized with the system clock, and might have
311  * problems with time stamps for packets received on different CPUs,
312  * depending on the platform.
313  *
314  * PCAP_TSTAMP_ADAPTER is a high-precision time stamp supplied by the
315  * capture device; it's synchronized with the system clock.
316  *
317  * PCAP_TSTAMP_ADAPTER_UNSYNCED is a high-precision time stamp supplied by
318  * the capture device; it's not synchronized with the system clock.
319  *
320  * Note that time stamps synchronized with the system clock can go
321  * backwards, as the system clock can go backwards.  If a clock is
322  * not in sync with the system clock, that could be because the
323  * system clock isn't keeping accurate time, because the other
324  * clock isn't keeping accurate time, or both.
325  *
326  * Note that host-provided time stamps generally correspond to the
327  * time when the time-stamping code sees the packet; this could
328  * be some unknown amount of time after the first or last bit of
329  * the packet is received by the network adapter, due to batching
330  * of interrupts for packet arrival, queueing delays, etc..
331  */
332 #define PCAP_TSTAMP_HOST		0	/* host-provided, unknown characteristics */
333 #define PCAP_TSTAMP_HOST_LOWPREC	1	/* host-provided, low precision */
334 #define PCAP_TSTAMP_HOST_HIPREC		2	/* host-provided, high precision */
335 #define PCAP_TSTAMP_ADAPTER		3	/* device-provided, synced with the system clock */
336 #define PCAP_TSTAMP_ADAPTER_UNSYNCED	4	/* device-provided, not synced with the system clock */
337 
338 /*
339  * Time stamp resolution types.
340  * Not all systems and interfaces will necessarily support all of these
341  * resolutions when doing live captures; all of them can be requested
342  * when reading a savefile.
343  */
344 #define PCAP_TSTAMP_PRECISION_MICRO	0	/* use timestamps with microsecond precision, default */
345 #define PCAP_TSTAMP_PRECISION_NANO	1	/* use timestamps with nanosecond precision */
346 
347 pcap_t	*pcap_open_live(const char *, int, int, int, char *);
348 pcap_t	*pcap_open_dead(int, int);
349 pcap_t	*pcap_open_dead_with_tstamp_precision(int, int, u_int);
350 pcap_t	*pcap_open_offline_with_tstamp_precision(const char *, u_int, char *);
351 pcap_t	*pcap_open_offline(const char *, char *);
352 #if defined(WIN32)
353 pcap_t  *pcap_hopen_offline_with_tstamp_precision(intptr_t, u_int, char *);
354 pcap_t  *pcap_hopen_offline(intptr_t, char *);
355 #if !defined(LIBPCAP_EXPORTS)
356 #define pcap_fopen_offline_with_tstamp_precision(f,p,b) \
357 	pcap_hopen_offline_with_tstamp_precision(_get_osfhandle(_fileno(f)), p, b)
358 #define pcap_fopen_offline(f,b) \
359 	pcap_hopen_offline(_get_osfhandle(_fileno(f)), b)
360 #else /*LIBPCAP_EXPORTS*/
361 static pcap_t *pcap_fopen_offline_with_tstamp_precision(FILE *, u_int, char *);
362 static pcap_t *pcap_fopen_offline(FILE *, char *);
363 #endif
364 #else /*WIN32*/
365 pcap_t	*pcap_fopen_offline_with_tstamp_precision(FILE *, u_int, char *);
366 pcap_t	*pcap_fopen_offline(FILE *, char *);
367 #endif /*WIN32*/
368 
369 void	pcap_close(pcap_t *);
370 int	pcap_loop(pcap_t *, int, pcap_handler, u_char *);
371 int	pcap_dispatch(pcap_t *, int, pcap_handler, u_char *);
372 const u_char*
373 	pcap_next(pcap_t *, struct pcap_pkthdr *);
374 int 	pcap_next_ex(pcap_t *, struct pcap_pkthdr **, const u_char **);
375 void	pcap_breakloop(pcap_t *);
376 int	pcap_stats(pcap_t *, struct pcap_stat *);
377 int	pcap_setfilter(pcap_t *, struct bpf_program *);
378 int 	pcap_setdirection(pcap_t *, pcap_direction_t);
379 int	pcap_getnonblock(pcap_t *, char *);
380 int	pcap_setnonblock(pcap_t *, int, char *);
381 int	pcap_inject(pcap_t *, const void *, size_t);
382 int	pcap_sendpacket(pcap_t *, const u_char *, int);
383 const char *pcap_statustostr(int);
384 const char *pcap_strerror(int);
385 char	*pcap_geterr(pcap_t *);
386 void	pcap_perror(pcap_t *, char *);
387 int	pcap_compile(pcap_t *, struct bpf_program *, const char *, int,
388 	    bpf_u_int32);
389 int	pcap_compile_nopcap(int, int, struct bpf_program *,
390 	    const char *, int, bpf_u_int32);
391 void	pcap_freecode(struct bpf_program *);
392 int	pcap_offline_filter(const struct bpf_program *,
393 	    const struct pcap_pkthdr *, const u_char *);
394 int	pcap_datalink(pcap_t *);
395 int	pcap_datalink_ext(pcap_t *);
396 int	pcap_list_datalinks(pcap_t *, int **);
397 int	pcap_set_datalink(pcap_t *, int);
398 void	pcap_free_datalinks(int *);
399 int	pcap_datalink_name_to_val(const char *);
400 const char *pcap_datalink_val_to_name(int);
401 const char *pcap_datalink_val_to_description(int);
402 int	pcap_snapshot(pcap_t *);
403 int	pcap_is_swapped(pcap_t *);
404 int	pcap_major_version(pcap_t *);
405 int	pcap_minor_version(pcap_t *);
406 
407 /* XXX */
408 FILE	*pcap_file(pcap_t *);
409 int	pcap_fileno(pcap_t *);
410 
411 pcap_dumper_t *pcap_dump_open(pcap_t *, const char *);
412 pcap_dumper_t *pcap_dump_fopen(pcap_t *, FILE *fp);
413 FILE	*pcap_dump_file(pcap_dumper_t *);
414 long	pcap_dump_ftell(pcap_dumper_t *);
415 int	pcap_dump_flush(pcap_dumper_t *);
416 void	pcap_dump_close(pcap_dumper_t *);
417 void	pcap_dump(u_char *, const struct pcap_pkthdr *, const u_char *);
418 
419 int	pcap_findalldevs(pcap_if_t **, char *);
420 void	pcap_freealldevs(pcap_if_t *);
421 
422 const char *pcap_lib_version(void);
423 
424 /*
425  * On at least some versions of NetBSD, we don't want to declare
426  * bpf_filter() here, as it's also be declared in <net/bpf.h>, with a
427  * different signature, but, on other BSD-flavored UN*Xes, it's not
428  * declared in <net/bpf.h>, so we *do* want to declare it here, so it's
429  * declared when we build pcap-bpf.c.
430  */
431 #ifndef __NetBSD__
432 u_int	bpf_filter(const struct bpf_insn *, const u_char *, u_int, u_int);
433 #endif
434 int	bpf_validate(const struct bpf_insn *f, int len);
435 char	*bpf_image(const struct bpf_insn *, int);
436 void	bpf_dump(const struct bpf_program *, int);
437 
438 #if defined(WIN32)
439 
440 /*
441  * Win32 definitions
442  */
443 
444 int pcap_setbuff(pcap_t *p, int dim);
445 int pcap_setmode(pcap_t *p, int mode);
446 int pcap_setmintocopy(pcap_t *p, int size);
447 Adapter *pcap_get_adapter(pcap_t *p);
448 
449 #ifdef WPCAP
450 /* Include file with the wpcap-specific extensions */
451 #include <Win32-Extensions.h>
452 #endif /* WPCAP */
453 
454 #define MODE_CAPT 0
455 #define MODE_STAT 1
456 #define MODE_MON 2
457 
458 #elif defined(MSDOS)
459 
460 /*
461  * MS-DOS definitions
462  */
463 
464 int  pcap_stats_ex (pcap_t *, struct pcap_stat_ex *);
465 void pcap_set_wait (pcap_t *p, void (*yield)(void), int wait);
466 u_long pcap_mac_packets (void);
467 
468 #else /* UN*X */
469 
470 /*
471  * UN*X definitions
472  */
473 
474 int	pcap_get_selectable_fd(pcap_t *);
475 
476 #endif /* WIN32/MSDOS/UN*X */
477 
478 #ifdef __cplusplus
479 }
480 #endif
481 
482 #endif /* lib_pcap_pcap_h */
483