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      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 #ifndef PCAP_DONT_INCLUDE_PCAP_BPF_H
     49 #include <pcap/bpf.h>
     50 #endif
     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 (at) 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/the-tcpdump-group/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 #define PCAP_IF_UP		0x00000002	/* interface is up */
    224 #define PCAP_IF_RUNNING		0x00000004	/* interface is running */
    225 
    226 /*
    227  * Representation of an interface address.
    228  */
    229 struct pcap_addr {
    230 	struct pcap_addr *next;
    231 	struct sockaddr *addr;		/* address */
    232 	struct sockaddr *netmask;	/* netmask for that address */
    233 	struct sockaddr *broadaddr;	/* broadcast address for that address */
    234 	struct sockaddr *dstaddr;	/* P2P destination address for that address */
    235 };
    236 
    237 typedef void (*pcap_handler)(u_char *, const struct pcap_pkthdr *,
    238 			     const u_char *);
    239 
    240 /*
    241  * Error codes for the pcap API.
    242  * These will all be negative, so you can check for the success or
    243  * failure of a call that returns these codes by checking for a
    244  * negative value.
    245  */
    246 #define PCAP_ERROR			-1	/* generic error code */
    247 #define PCAP_ERROR_BREAK		-2	/* loop terminated by pcap_breakloop */
    248 #define PCAP_ERROR_NOT_ACTIVATED	-3	/* the capture needs to be activated */
    249 #define PCAP_ERROR_ACTIVATED		-4	/* the operation can't be performed on already activated captures */
    250 #define PCAP_ERROR_NO_SUCH_DEVICE	-5	/* no such device exists */
    251 #define PCAP_ERROR_RFMON_NOTSUP		-6	/* this device doesn't support rfmon (monitor) mode */
    252 #define PCAP_ERROR_NOT_RFMON		-7	/* operation supported only in monitor mode */
    253 #define PCAP_ERROR_PERM_DENIED		-8	/* no permission to open the device */
    254 #define PCAP_ERROR_IFACE_NOT_UP		-9	/* interface isn't up */
    255 #define PCAP_ERROR_CANTSET_TSTAMP_TYPE	-10	/* this device doesn't support setting the time stamp type */
    256 #define PCAP_ERROR_PROMISC_PERM_DENIED	-11	/* you don't have permission to capture in promiscuous mode */
    257 #define PCAP_ERROR_TSTAMP_PRECISION_NOTSUP -12  /* the requested time stamp precision is not supported */
    258 
    259 /*
    260  * Warning codes for the pcap API.
    261  * These will all be positive and non-zero, so they won't look like
    262  * errors.
    263  */
    264 #define PCAP_WARNING			1	/* generic warning code */
    265 #define PCAP_WARNING_PROMISC_NOTSUP	2	/* this device doesn't support promiscuous mode */
    266 #define PCAP_WARNING_TSTAMP_TYPE_NOTSUP	3	/* the requested time stamp type is not supported */
    267 
    268 /*
    269  * Value to pass to pcap_compile() as the netmask if you don't know what
    270  * the netmask is.
    271  */
    272 #define PCAP_NETMASK_UNKNOWN	0xffffffff
    273 
    274 char	*pcap_lookupdev(char *);
    275 int	pcap_lookupnet(const char *, bpf_u_int32 *, bpf_u_int32 *, char *);
    276 
    277 pcap_t	*pcap_create(const char *, char *);
    278 int	pcap_set_snaplen(pcap_t *, int);
    279 int	pcap_set_promisc(pcap_t *, int);
    280 int	pcap_can_set_rfmon(pcap_t *);
    281 int	pcap_set_rfmon(pcap_t *, int);
    282 int	pcap_set_timeout(pcap_t *, int);
    283 int	pcap_set_tstamp_type(pcap_t *, int);
    284 int	pcap_set_immediate_mode(pcap_t *, int);
    285 int	pcap_set_buffer_size(pcap_t *, int);
    286 int	pcap_set_tstamp_precision(pcap_t *, int);
    287 int	pcap_get_tstamp_precision(pcap_t *);
    288 int	pcap_activate(pcap_t *);
    289 
    290 int	pcap_list_tstamp_types(pcap_t *, int **);
    291 void	pcap_free_tstamp_types(int *);
    292 int	pcap_tstamp_type_name_to_val(const char *);
    293 const char *pcap_tstamp_type_val_to_name(int);
    294 const char *pcap_tstamp_type_val_to_description(int);
    295 
    296 /*
    297  * Time stamp types.
    298  * Not all systems and interfaces will necessarily support all of these.
    299  *
    300  * A system that supports PCAP_TSTAMP_HOST is offering time stamps
    301  * provided by the host machine, rather than by the capture device,
    302  * but not committing to any characteristics of the time stamp;
    303  * it will not offer any of the PCAP_TSTAMP_HOST_ subtypes.
    304  *
    305  * PCAP_TSTAMP_HOST_LOWPREC is a time stamp, provided by the host machine,
    306  * that's low-precision but relatively cheap to fetch; it's normally done
    307  * using the system clock, so it's normally synchronized with times you'd
    308  * fetch from system calls.
    309  *
    310  * PCAP_TSTAMP_HOST_HIPREC is a time stamp, provided by the host machine,
    311  * that's high-precision; it might be more expensive to fetch.  It might
    312  * or might not be synchronized with the system clock, and might have
    313  * problems with time stamps for packets received on different CPUs,
    314  * depending on the platform.
    315  *
    316  * PCAP_TSTAMP_ADAPTER is a high-precision time stamp supplied by the
    317  * capture device; it's synchronized with the system clock.
    318  *
    319  * PCAP_TSTAMP_ADAPTER_UNSYNCED is a high-precision time stamp supplied by
    320  * the capture device; it's not synchronized with the system clock.
    321  *
    322  * Note that time stamps synchronized with the system clock can go
    323  * backwards, as the system clock can go backwards.  If a clock is
    324  * not in sync with the system clock, that could be because the
    325  * system clock isn't keeping accurate time, because the other
    326  * clock isn't keeping accurate time, or both.
    327  *
    328  * Note that host-provided time stamps generally correspond to the
    329  * time when the time-stamping code sees the packet; this could
    330  * be some unknown amount of time after the first or last bit of
    331  * the packet is received by the network adapter, due to batching
    332  * of interrupts for packet arrival, queueing delays, etc..
    333  */
    334 #define PCAP_TSTAMP_HOST		0	/* host-provided, unknown characteristics */
    335 #define PCAP_TSTAMP_HOST_LOWPREC	1	/* host-provided, low precision */
    336 #define PCAP_TSTAMP_HOST_HIPREC		2	/* host-provided, high precision */
    337 #define PCAP_TSTAMP_ADAPTER		3	/* device-provided, synced with the system clock */
    338 #define PCAP_TSTAMP_ADAPTER_UNSYNCED	4	/* device-provided, not synced with the system clock */
    339 
    340 /*
    341  * Time stamp resolution types.
    342  * Not all systems and interfaces will necessarily support all of these
    343  * resolutions when doing live captures; all of them can be requested
    344  * when reading a savefile.
    345  */
    346 #define PCAP_TSTAMP_PRECISION_MICRO	0	/* use timestamps with microsecond precision, default */
    347 #define PCAP_TSTAMP_PRECISION_NANO	1	/* use timestamps with nanosecond precision */
    348 
    349 pcap_t	*pcap_open_live(const char *, int, int, int, char *);
    350 pcap_t	*pcap_open_dead(int, int);
    351 pcap_t	*pcap_open_dead_with_tstamp_precision(int, int, u_int);
    352 pcap_t	*pcap_open_offline_with_tstamp_precision(const char *, u_int, char *);
    353 pcap_t	*pcap_open_offline(const char *, char *);
    354 #if defined(WIN32)
    355 pcap_t  *pcap_hopen_offline_with_tstamp_precision(intptr_t, u_int, char *);
    356 pcap_t  *pcap_hopen_offline(intptr_t, char *);
    357 #if !defined(LIBPCAP_EXPORTS)
    358 #define pcap_fopen_offline_with_tstamp_precision(f,p,b) \
    359 	pcap_hopen_offline_with_tstamp_precision(_get_osfhandle(_fileno(f)), p, b)
    360 #define pcap_fopen_offline(f,b) \
    361 	pcap_hopen_offline(_get_osfhandle(_fileno(f)), b)
    362 #else /*LIBPCAP_EXPORTS*/
    363 static pcap_t *pcap_fopen_offline_with_tstamp_precision(FILE *, u_int, char *);
    364 static pcap_t *pcap_fopen_offline(FILE *, char *);
    365 #endif
    366 #else /*WIN32*/
    367 pcap_t	*pcap_fopen_offline_with_tstamp_precision(FILE *, u_int, char *);
    368 pcap_t	*pcap_fopen_offline(FILE *, char *);
    369 #endif /*WIN32*/
    370 
    371 void	pcap_close(pcap_t *);
    372 int	pcap_loop(pcap_t *, int, pcap_handler, u_char *);
    373 int	pcap_dispatch(pcap_t *, int, pcap_handler, u_char *);
    374 const u_char*
    375 	pcap_next(pcap_t *, struct pcap_pkthdr *);
    376 int 	pcap_next_ex(pcap_t *, struct pcap_pkthdr **, const u_char **);
    377 void	pcap_breakloop(pcap_t *);
    378 int	pcap_stats(pcap_t *, struct pcap_stat *);
    379 int	pcap_setfilter(pcap_t *, struct bpf_program *);
    380 int 	pcap_setdirection(pcap_t *, pcap_direction_t);
    381 int	pcap_getnonblock(pcap_t *, char *);
    382 int	pcap_setnonblock(pcap_t *, int, char *);
    383 int	pcap_inject(pcap_t *, const void *, size_t);
    384 int	pcap_sendpacket(pcap_t *, const u_char *, int);
    385 const char *pcap_statustostr(int);
    386 const char *pcap_strerror(int);
    387 char	*pcap_geterr(pcap_t *);
    388 void	pcap_perror(pcap_t *, char *);
    389 int	pcap_compile(pcap_t *, struct bpf_program *, const char *, int,
    390 	    bpf_u_int32);
    391 int	pcap_compile_nopcap(int, int, struct bpf_program *,
    392 	    const char *, int, bpf_u_int32);
    393 void	pcap_freecode(struct bpf_program *);
    394 int	pcap_offline_filter(const struct bpf_program *,
    395 	    const struct pcap_pkthdr *, const u_char *);
    396 int	pcap_datalink(pcap_t *);
    397 int	pcap_datalink_ext(pcap_t *);
    398 int	pcap_list_datalinks(pcap_t *, int **);
    399 int	pcap_set_datalink(pcap_t *, int);
    400 void	pcap_free_datalinks(int *);
    401 int	pcap_datalink_name_to_val(const char *);
    402 const char *pcap_datalink_val_to_name(int);
    403 const char *pcap_datalink_val_to_description(int);
    404 int	pcap_snapshot(pcap_t *);
    405 int	pcap_is_swapped(pcap_t *);
    406 int	pcap_major_version(pcap_t *);
    407 int	pcap_minor_version(pcap_t *);
    408 
    409 /* XXX */
    410 FILE	*pcap_file(pcap_t *);
    411 int	pcap_fileno(pcap_t *);
    412 
    413 pcap_dumper_t *pcap_dump_open(pcap_t *, const char *);
    414 pcap_dumper_t *pcap_dump_fopen(pcap_t *, FILE *fp);
    415 pcap_dumper_t *pcap_dump_open_append(pcap_t *, const char *);
    416 FILE	*pcap_dump_file(pcap_dumper_t *);
    417 long	pcap_dump_ftell(pcap_dumper_t *);
    418 int	pcap_dump_flush(pcap_dumper_t *);
    419 void	pcap_dump_close(pcap_dumper_t *);
    420 void	pcap_dump(u_char *, const struct pcap_pkthdr *, const u_char *);
    421 
    422 int	pcap_findalldevs(pcap_if_t **, char *);
    423 void	pcap_freealldevs(pcap_if_t *);
    424 
    425 const char *pcap_lib_version(void);
    426 
    427 /*
    428  * On at least some versions of NetBSD and QNX, we don't want to declare
    429  * bpf_filter() here, as it's also be declared in <net/bpf.h>, with a
    430  * different signature, but, on other BSD-flavored UN*Xes, it's not
    431  * declared in <net/bpf.h>, so we *do* want to declare it here, so it's
    432  * declared when we build pcap-bpf.c.
    433  */
    434 #if !defined(__NetBSD__) && !defined(__QNX__)
    435 u_int	bpf_filter(const struct bpf_insn *, const u_char *, u_int, u_int);
    436 #endif
    437 int	bpf_validate(const struct bpf_insn *f, int len);
    438 char	*bpf_image(const struct bpf_insn *, int);
    439 void	bpf_dump(const struct bpf_program *, int);
    440 
    441 #if defined(WIN32)
    442 
    443 /*
    444  * Win32 definitions
    445  */
    446 
    447 int pcap_setbuff(pcap_t *p, int dim);
    448 int pcap_setmode(pcap_t *p, int mode);
    449 int pcap_setmintocopy(pcap_t *p, int size);
    450 Adapter *pcap_get_adapter(pcap_t *p);
    451 
    452 #ifdef WPCAP
    453 /* Include file with the wpcap-specific extensions */
    454 #include <Win32-Extensions.h>
    455 #endif /* WPCAP */
    456 
    457 #define MODE_CAPT 0
    458 #define MODE_STAT 1
    459 #define MODE_MON 2
    460 
    461 #elif defined(MSDOS)
    462 
    463 /*
    464  * MS-DOS definitions
    465  */
    466 
    467 int  pcap_stats_ex (pcap_t *, struct pcap_stat_ex *);
    468 void pcap_set_wait (pcap_t *p, void (*yield)(void), int wait);
    469 u_long pcap_mac_packets (void);
    470 
    471 #else /* UN*X */
    472 
    473 /*
    474  * UN*X definitions
    475  */
    476 
    477 int	pcap_get_selectable_fd(pcap_t *);
    478 
    479 #endif /* WIN32/MSDOS/UN*X */
    480 
    481 #ifdef __cplusplus
    482 }
    483 #endif
    484 
    485 #endif /* lib_pcap_pcap_h */
    486