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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@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 FILE    *pcap_dump_file(pcap_dumper_t *);
 416 long    pcap_dump_ftell(pcap_dumper_t *);
 417 int     pcap_dump_flush(pcap_dumper_t *);
 418 void    pcap_dump_close(pcap_dumper_t *);
 419 void    pcap_dump(u_char *, const struct pcap_pkthdr *, const u_char *);
 420
 421 int     pcap_findalldevs(pcap_if_t **, char *);
 422 void    pcap_freealldevs(pcap_if_t *);
 423
 424 const char *pcap_lib_version(void);
 425
 426 /*
 427  * On at least some versions of NetBSD, we don't want to declare
 428  * bpf_filter() here, as it's also be declared in <net/bpf.h>, with a
 429  * different signature, but, on other BSD-flavored UN*Xes, it's not
 430  * declared in <net/bpf.h>, so we *do* want to declare it here, so it's
 431  * declared when we build pcap-bpf.c.
 432  */
 433 #ifndef __NetBSD__
 434 u_int   bpf_filter(const struct bpf_insn *, const u_char *, u_int, u_int);
 435 #endif
 436 int     bpf_validate(const struct bpf_insn *f, int len);
 437 char    *bpf_image(const struct bpf_insn *, int);
 438 void    bpf_dump(const struct bpf_program *, int);
 439
 440 #if defined(WIN32)
 441
 442 /*
 443  * Win32 definitions
 444  */
 445
 446 int pcap_setbuff(pcap_t *p, int dim);
 447 int pcap_setmode(pcap_t *p, int mode);
 448 int pcap_setmintocopy(pcap_t *p, int size);
 449 Adapter *pcap_get_adapter(pcap_t *p);
 450
 451 #ifdef WPCAP
 452 /* Include file with the wpcap-specific extensions */
 453 #include <Win32-Extensions.h>
 454 #endif /* WPCAP */
 455
 456 #define MODE_CAPT 0
 457 #define MODE_STAT 1
 458 #define MODE_MON 2
 459
 460 #elif defined(MSDOS)
 461
 462 /*
 463  * MS-DOS definitions
 464  */
 465
 466 int  pcap_stats_ex (pcap_t *, struct pcap_stat_ex *);
 467 void pcap_set_wait (pcap_t *p, void (*yield)(void), int wait);
 468 u_long pcap_mac_packets (void);
 469
 470 #else /* UN*X */
 471
 472 /*
 473  * UN*X definitions
 474  */
 475
 476 int     pcap_get_selectable_fd(pcap_t *);
 477
 478 #endif /* WIN32/MSDOS/UN*X */
 479
 480 #ifdef __cplusplus
 481 }
 482 #endif
 483
 484 #endif /* lib_pcap_pcap_h */