The Tcpdump Group git mirrors - libpcap/blob - pcap-int.h

   1 /*
   2  * Copyright (c) 1994, 1995, 1996
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the Computer Systems
  16  *      Engineering Group at Lawrence Berkeley Laboratory.
  17  * 4. Neither the name of the University nor of the Laboratory may be used
  18  *    to endorse or promote products derived from this software without
  19  *    specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #ifndef pcap_int_h
  35 #define pcap_int_h
  36
  37 #include <pcap/pcap.h>
  38
  39 #ifdef __cplusplus
  40 extern "C" {
  41 #endif
  42
  43 #ifdef WIN32
  44 #include <Packet32.h>
  45 extern CRITICAL_SECTION g_PcapCompileCriticalSection;
  46 #endif /* WIN32 */
  47
  48 #ifdef MSDOS
  49 #include <fcntl.h>
  50 #include <io.h>
  51 #endif
  52
  53 #if (defined(_MSC_VER) && (_MSC_VER <= 1200)) /* we are compiling with Visual Studio 6, that doesn't support the LL suffix*/
  54
  55 /*
  56  * Swap byte ordering of unsigned long long timestamp on a big endian
  57  * machine.
  58  */
  59 #define SWAPLL(ull)  ((ull & 0xff00000000000000) >> 56) | \
  60                       ((ull & 0x00ff000000000000) >> 40) | \
  61                       ((ull & 0x0000ff0000000000) >> 24) | \
  62                       ((ull & 0x000000ff00000000) >> 8)  | \
  63                       ((ull & 0x00000000ff000000) << 8)  | \
  64                       ((ull & 0x0000000000ff0000) << 24) | \
  65                       ((ull & 0x000000000000ff00) << 40) | \
  66                       ((ull & 0x00000000000000ff) << 56)
  67
  68 #else /* A recent Visual studio compiler or not VC */
  69
  70 /*
  71  * Swap byte ordering of unsigned long long timestamp on a big endian
  72  * machine.
  73  */
  74 #define SWAPLL(ull)  ((ull & 0xff00000000000000LL) >> 56) | \
  75                       ((ull & 0x00ff000000000000LL) >> 40) | \
  76                       ((ull & 0x0000ff0000000000LL) >> 24) | \
  77                       ((ull & 0x000000ff00000000LL) >> 8)  | \
  78                       ((ull & 0x00000000ff000000LL) << 8)  | \
  79                       ((ull & 0x0000000000ff0000LL) << 24) | \
  80                       ((ull & 0x000000000000ff00LL) << 40) | \
  81                       ((ull & 0x00000000000000ffLL) << 56)
  82
  83 #endif /* _MSC_VER */
  84
  85 struct pcap_opt {
  86         char    *source;
  87         int     timeout;        /* timeout for buffering */
  88         int     buffer_size;
  89         int     promisc;
  90         int     rfmon;          /* monitor mode */
  91         int     immediate;      /* immediate mode - deliver packets as soon as they arrive */
  92         int     tstamp_type;
  93         int     tstamp_precision;
  94 };
  95
  96 typedef int     (*activate_op_t)(pcap_t *);
  97 typedef int     (*can_set_rfmon_op_t)(pcap_t *);
  98 typedef int     (*read_op_t)(pcap_t *, int cnt, pcap_handler, u_char *);
  99 typedef int     (*inject_op_t)(pcap_t *, const void *, size_t);
 100 typedef int     (*setfilter_op_t)(pcap_t *, struct bpf_program *);
 101 typedef int     (*setdirection_op_t)(pcap_t *, pcap_direction_t);
 102 typedef int     (*set_datalink_op_t)(pcap_t *, int);
 103 typedef int     (*getnonblock_op_t)(pcap_t *, char *);
 104 typedef int     (*setnonblock_op_t)(pcap_t *, int, char *);
 105 typedef int     (*stats_op_t)(pcap_t *, struct pcap_stat *);
 106 #ifdef WIN32
 107 typedef int     (*setbuff_op_t)(pcap_t *, int);
 108 typedef int     (*setmode_op_t)(pcap_t *, int);
 109 typedef int     (*setmintocopy_op_t)(pcap_t *, int);
 110 typedef Adapter *(*getadapter_op_t)(pcap_t *);
 111 #endif
 112 typedef void    (*cleanup_op_t)(pcap_t *);
 113
 114 /*
 115  * We put all the stuff used in the read code path at the beginning,
 116  * to try to keep it together in the same cache line or lines.
 117  */
 118 struct pcap {
 119         /*
 120          * Method to call to read packets on a live capture.
 121          */
 122         read_op_t read_op;
 123
 124         /*
 125          * Method to call to read to read packets from a savefile.
 126          */
 127         int (*next_packet_op)(pcap_t *, struct pcap_pkthdr *, u_char **);
 128
 129 #ifdef WIN32
 130         ADAPTER *adapter;
 131         LPPACKET Packet;
 132         int nonblock;
 133 #else
 134         int fd;
 135         int selectable_fd;
 136 #endif /* WIN32 */
 137
 138         /*
 139          * Read buffer.
 140          */
 141         int bufsize;
 142         u_char *buffer;
 143         u_char *bp;
 144         int cc;
 145
 146         int break_loop;         /* flag set to force break from packet-reading loop */
 147
 148         void *priv;             /* private data for methods */
 149
 150         int swapped;
 151         FILE *rfile;            /* null if live capture, non-null if savefile */
 152         int fddipad;
 153         struct pcap *next;      /* list of open pcaps that need stuff cleared on close */
 154
 155         /*
 156          * File version number; meaningful only for a savefile, but we
 157          * keep it here so that apps that (mistakenly) ask for the
 158          * version numbers will get the same zero values that they
 159          * always did.
 160          */
 161         int version_major;
 162         int version_minor;
 163
 164         int snapshot;
 165         int linktype;           /* Network linktype */
 166         int linktype_ext;       /* Extended information stored in the linktype field of a file */
 167         int tzoff;              /* timezone offset */
 168         int offset;             /* offset for proper alignment */
 169         int activated;          /* true if the capture is really started */
 170         int oldstyle;           /* if we're opening with pcap_open_live() */
 171
 172         struct pcap_opt opt;
 173
 174         /*
 175          * Place holder for pcap_next().
 176          */
 177         u_char *pkt;
 178
 179         /* We're accepting only packets in this direction/these directions. */
 180         pcap_direction_t direction;
 181
 182         /*
 183          * Placeholder for filter code if bpf not in kernel.
 184          */
 185         struct bpf_program fcode;
 186
 187         char errbuf[PCAP_ERRBUF_SIZE + 1];
 188         int dlt_count;
 189         u_int *dlt_list;
 190         int tstamp_type_count;
 191         u_int *tstamp_type_list;
 192         int tstamp_precision_count;
 193         u_int *tstamp_precision_list;
 194
 195         struct pcap_pkthdr pcap_header; /* This is needed for the pcap_next_ex() to work */
 196
 197         /*
 198          * More methods.
 199          */
 200         activate_op_t activate_op;
 201         can_set_rfmon_op_t can_set_rfmon_op;
 202         inject_op_t inject_op;
 203         setfilter_op_t setfilter_op;
 204         setdirection_op_t setdirection_op;
 205         set_datalink_op_t set_datalink_op;
 206         getnonblock_op_t getnonblock_op;
 207         setnonblock_op_t setnonblock_op;
 208         stats_op_t stats_op;
 209
 210         /*
 211          * Routine to use as callback for pcap_next()/pcap_next_ex().
 212          */
 213         pcap_handler oneshot_callback;
 214
 215 #ifdef WIN32
 216         /*
 217          * These are, at least currently, specific to the Win32 NPF
 218          * driver.
 219          */
 220         setbuff_op_t setbuff_op;
 221         setmode_op_t setmode_op;
 222         setmintocopy_op_t setmintocopy_op;
 223         getadapter_op_t getadapter_op;
 224 #endif
 225         cleanup_op_t cleanup_op;
 226 };
 227
 228 /*
 229  * This is a timeval as stored in a savefile.
 230  * It has to use the same types everywhere, independent of the actual
 231  * `struct timeval'; `struct timeval' has 32-bit tv_sec values on some
 232  * platforms and 64-bit tv_sec values on other platforms, and writing
 233  * out native `struct timeval' values would mean files could only be
 234  * read on systems with the same tv_sec size as the system on which
 235  * the file was written.
 236  */
 237
 238 struct pcap_timeval {
 239     bpf_int32 tv_sec;           /* seconds */
 240     bpf_int32 tv_usec;          /* microseconds */
 241 };
 242
 243 /*
 244  * This is a `pcap_pkthdr' as actually stored in a savefile.
 245  *
 246  * Do not change the format of this structure, in any way (this includes
 247  * changes that only affect the length of fields in this structure),
 248  * and do not make the time stamp anything other than seconds and
 249  * microseconds (e.g., seconds and nanoseconds).  Instead:
 250  *
 251  *      introduce a new structure for the new format;
 252  *
 253  *      send mail to "tcpdump-workers@lists.tcpdump.org", requesting
 254  *      a new magic number for your new capture file format, and, when
 255  *      you get the new magic number, put it in "savefile.c";
 256  *
 257  *      use that magic number for save files with the changed record
 258  *      header;
 259  *
 260  *      make the code in "savefile.c" capable of reading files with
 261  *      the old record header as well as files with the new record header
 262  *      (using the magic number to determine the header format).
 263  *
 264  * Then supply the changes by forking the branch at
 265  *
 266  *      https://github.com/the-tcpdump-group/libpcap/issues
 267  *
 268  * and issuing a pull request, so that future versions of libpcap and
 269  * programs that use it (such as tcpdump) will be able to read your new
 270  * capture file format.
 271  */
 272
 273 struct pcap_sf_pkthdr {
 274     struct pcap_timeval ts;     /* time stamp */
 275     bpf_u_int32 caplen;         /* length of portion present */
 276     bpf_u_int32 len;            /* length this packet (off wire) */
 277 };
 278
 279 /*
 280  * How a `pcap_pkthdr' is actually stored in savefiles written
 281  * by some patched versions of libpcap (e.g. the ones in Red
 282  * Hat Linux 6.1 and 6.2).
 283  *
 284  * Do not change the format of this structure, in any way (this includes
 285  * changes that only affect the length of fields in this structure).
 286  * Instead, introduce a new structure, as per the above.
 287  */
 288
 289 struct pcap_sf_patched_pkthdr {
 290     struct pcap_timeval ts;     /* time stamp */
 291     bpf_u_int32 caplen;         /* length of portion present */
 292     bpf_u_int32 len;            /* length this packet (off wire) */
 293     int         index;
 294     unsigned short protocol;
 295     unsigned char pkt_type;
 296 };
 297
 298 /*
 299  * User data structure for the one-shot callback used for pcap_next()
 300  * and pcap_next_ex().
 301  */
 302 struct oneshot_userdata {
 303         struct pcap_pkthdr *hdr;
 304         const u_char **pkt;
 305         pcap_t *pd;
 306 };
 307
 308 int     yylex(void);
 309
 310 #ifndef min
 311 #define min(a, b) ((a) > (b) ? (b) : (a))
 312 #endif
 313
 314 /* XXX should these be in pcap.h? */
 315 int     pcap_offline_read(pcap_t *, int, pcap_handler, u_char *);
 316 int     pcap_read(pcap_t *, int cnt, pcap_handler, u_char *);
 317
 318 #ifndef HAVE_STRLCPY
 319 #define strlcpy(x, y, z) \
 320         (strncpy((x), (y), (z)), \
 321          ((z) <= 0 ? 0 : ((x)[(z) - 1] = '\0')), \
 322          strlen((y)))
 323 #endif
 324
 325 #include <stdarg.h>
 326
 327 #if !defined(HAVE_SNPRINTF)
 328 #define snprintf pcap_snprintf
 329 extern int snprintf (char *, size_t, const char *, ...);
 330 #endif
 331
 332 #if !defined(HAVE_VSNPRINTF)
 333 #define vsnprintf pcap_vsnprintf
 334 extern int vsnprintf (char *, size_t, const char *, va_list ap);
 335 #endif
 336
 337 /*
 338  * Does the packet count argument to a module's read routine say
 339  * "supply packets until you run out of packets"?
 340  */
 341 #define PACKET_COUNT_IS_UNLIMITED(count)        ((count) <= 0)
 342
 343 /*
 344  * Routines that most pcap implementations can use for non-blocking mode.
 345  */
 346 #if !defined(WIN32) && !defined(MSDOS)
 347 int     pcap_getnonblock_fd(pcap_t *, char *);
 348 int     pcap_setnonblock_fd(pcap_t *p, int, char *);
 349 #endif
 350
 351 /*
 352  * Internal interfaces for "pcap_create()".
 353  *
 354  * "pcap_create_interface()" is the routine to do a pcap_create on
 355  * a regular network interface.  There are multiple implementations
 356  * of this, one for each platform type (Linux, BPF, DLPI, etc.),
 357  * with the one used chosen by the configure script.
 358  *
 359  * "pcap_create_common()" allocates and fills in a pcap_t, for use
 360  * by pcap_create routines.
 361  */
 362 pcap_t  *pcap_create_interface(const char *, char *);
 363 pcap_t  *pcap_create_common(const char *, char *, size_t);
 364 int     pcap_do_addexit(pcap_t *);
 365 void    pcap_add_to_pcaps_to_close(pcap_t *);
 366 void    pcap_remove_from_pcaps_to_close(pcap_t *);
 367 void    pcap_cleanup_live_common(pcap_t *);
 368 int     pcap_not_initialized(pcap_t *);
 369 int     pcap_check_activated(pcap_t *);
 370
 371 /*
 372  * Internal interfaces for "pcap_findalldevs()".
 373  *
 374  * "pcap_findalldevs_interfaces()" finds interfaces using the
 375  * "standard" mechanisms (SIOCGIFCONF, "getifaddrs()", etc.).
 376  *
 377  * "pcap_platform_finddevs()" is a platform-dependent routine to
 378  * add devices not found by the "standard" mechanisms.
 379  *
 380  * "pcap_add_if()" adds an interface to the list of interfaces, for
 381  * use by various "find interfaces" routines.
 382  */
 383 int     pcap_findalldevs_interfaces(pcap_if_t **, char *);
 384 int     pcap_platform_finddevs(pcap_if_t **, char *);
 385 int     add_addr_to_iflist(pcap_if_t **, const char *, u_int, struct sockaddr *,
 386             size_t, struct sockaddr *, size_t, struct sockaddr *, size_t,
 387             struct sockaddr *, size_t, char *);
 388 int     pcap_add_if(pcap_if_t **, const char *, u_int, const char *, char *);
 389 struct sockaddr *dup_sockaddr(struct sockaddr *, size_t);
 390 int     add_or_find_if(pcap_if_t **, pcap_if_t **, const char *, u_int,
 391             const char *, char *);
 392
 393 /*
 394  * Internal interfaces for "pcap_open_offline()".
 395  *
 396  * "pcap_open_offline_common()" allocates and fills in a pcap_t, for use
 397  * by pcap_open_offline routines.
 398  *
 399  * "sf_cleanup()" closes the file handle associated with a pcap_t, if
 400  * appropriate, and frees all data common to all modules for handling
 401  * savefile types.
 402  */
 403 pcap_t  *pcap_open_offline_common(char *ebuf, size_t size);
 404 void    sf_cleanup(pcap_t *p);
 405
 406 /*
 407  * Internal interfaces for both "pcap_create()" and routines that
 408  * open savefiles.
 409  *
 410  * "pcap_oneshot()" is the standard one-shot callback for "pcap_next()"
 411  * and "pcap_next_ex()".
 412  */
 413 void    pcap_oneshot(u_char *, const struct pcap_pkthdr *, const u_char *);
 414
 415 #ifdef WIN32
 416 char    *pcap_win32strerror(void);
 417 #endif
 418
 419 int     install_bpf_program(pcap_t *, struct bpf_program *);
 420
 421 int     pcap_strcasecmp(const char *, const char *);
 422
 423 #ifdef __cplusplus
 424 }
 425 #endif
 426
 427 #endif